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Sample records for modelling applying advanced

  1. Recent Turbulence Model Advances Applied to Multielement Airfoil Computations

    NASA Technical Reports Server (NTRS)

    Rumsey, Christopher L.; Gatski, Thomas B.

    2000-01-01

    A one-equation linear turbulence model and a two-equation nonlinear explicit algebraic stress model (EASM) are applied to the flow over a multielement airfoil. The effect of the K-epsilon and K-omega forms of the two-equation model are explored, and the K-epsilon form is shown to be deficient in the wall-bounded regions of adverse pressure gradient flows. A new K-omega form of EASM is introduced. Nonlinear terms present in EASM are shown to improve predictions of turbulent shear stress behind the trailing edge of the main element and near midflap. Curvature corrections are applied to both the one- and two-equation turbulence models and yield only relatively small local differences in the flap region, where the flow field undergoes the greatest curvature. Predictions of maximum lift are essentially unaffected by the turbulence model variations studied.

  2. Advanced Kinetic-Based Modeling Applied to Plasma and Neutral Flows

    DTIC Science & Technology

    2012-09-01

    Advanced Kinetic-Based Modeling Applied to Plasma and Neutral Flows Briefers: Andrew Ketsdever Sergey Gimelshein PIs: Andrew Ketsdever...number. 1. REPORT DATE SEP 2012 2. REPORT TYPE 3. DATES COVERED 00-00-2012 to 00-00-2012 4. TITLE AND SUBTITLE Advanced Kinetic-Based Modeling ...magnetic field in opposite direction of applied field Extreme pressure tends to drive plasma out of discharge chamber Difficulties in modeling FRCs High

  3. Advances in Exponential Random Graph (p*) Models Applied to a Large Social Network.

    PubMed

    Goodreau, Steven M

    2007-05-01

    Recent advances in statistical network analysis based on the family of exponential random graph (ERG) models have greatly improved our ability to conduct inference on dependence in large social networks (Snijders 2002, Pattison and Robins 2002, Handcock 2002, Handcock 2003, Snijders et al. 2006, Hunter et al. 2005, Goodreau et al. 2005, previous papers this issue). This paper applies advances in both model parameterizations and computational algorithms to an examination of the structure observed in an adolescent friendship network of 1,681 actors from the National Longitudinal Study of Adolescent Health (AddHealth). ERG models of social network structure are fit using the R package statnet, and their adequacy assessed through comparison of model predictions with the observed data for higher-order network statistics.For this friendship network, the commonly used model of Markov dependence leads to the problems of degeneracy discussed by Handcock (2002, 2003). On the other hand, model parameterizations introduced by Snijders et al (2006) and Hunter and Handcock (2006) avoid degeneracy and provide reasonable fit to the data. Degree-only models did a poor job of capturing observed network structure; those that did best included terms both for heterogeneous mixing on exogenous attributes (grade and self-reported race) as well as endogenous clustering. Networks simulated from this model were largely consistent with the observed network on multiple higher-order network statistics, including the number of triangles, the size of the largest component, the overall reachability, the distribution of geodesic distances, the degree distribution, and the shared partner distribution. The ability to fit such models to large datasets and to make inference about the underling processes generating the network represents a major advance in the field of statistical network analysis.

  4. Advanced geospatial technologies applied to gravel-bed river mapping and modeling

    NASA Astrophysics Data System (ADS)

    Aggett, Graeme Richard

    Mapping and modeling of river channels is essential in defining the Channel Migration Zone (CMZ). CMZ delineation is necessary to mitigate hazards, create opportunities to protect riparian habitat, predict channel response to changing land cover and disturbances, and design more environmentally-aligned engineering structures. This provides a compelling challenge to the GIScientist because of the need to understand fluvial process dynamics in space and time, and the narrow, elongated, and sinuous geometry of fluvial systems which complicates data collection, management and modeling of digital data describing these. This requires creation, management and correlation of a vast array of data of varying density and quality. Research presented here develops and applies advanced geospatial data, technologies, and modeling to CMZ mapping of a dynamic gravel-bed river in the state of Washington, USA. Chapter 2 demonstrates how new, object-based image processing techniques enhance river mapping accuracies and data modeling opportunities by incorporating the spatial characteristics and relationships of hydrogeomorphic objects into the classification process, by fusing high resolution DEMs with image data, and by accounting for uncertainty. In chapter 3, development and assimilation of a high resolution topographic LiDAR-based DEM with a one-dimensional hydraulic model enables the avulsion hazard of a reach of the Naches River in the state of Washington to be determined for multiple flow and channel-change scenarios. The DEM is used to optimize performance of the 1D hydraulic model HEC-RAS, post-processed output of which facilitates calculation of spatially explicit shear stress (tau0) and specific stream power per unit bed area (o). In Chapter 4 a new data intensive GIS-based framework for delineating CMZs is implemented and assessed. The approach incorporates historical maps, field-survey data, and LiDAR derived data products as well as a system design that provides a

  5. Modeling of Broadband Liners Applied to the Advanced Noise Control Fan

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.; Sutliff, Daniel L.

    2015-01-01

    The broadband component of fan noise has grown in relevance with an increase in bypass ratio and incorporation of advanced fan designs. Therefore, while the attenuation of fan tones remains a major factor in engine nacelle acoustic liner design, the simultaneous reduction of broadband fan noise levels has received increased interest. As such, a previous investigation focused on improvements to an established broadband acoustic liner optimization process using the Advanced Noise Control Fan (ANCF) rig as a demonstrator. Constant-depth, double-degree of freedom and variable-depth, multi-degree of freedom liner designs were carried through design, fabrication, and testing. This paper addresses a number of areas for further research identified in the initial assessment of the ANCF study. Specifically, incident source specification and uncertainty in some aspects of the predicted liner impedances are addressed. This information is incorporated in updated predictions of the liner performance and comparisons with measurement are greatly improved. Results illustrate the value of the design process in concurrently evaluating the relative costs/benefits of various liner designs. This study also provides further confidence in the integrated use of duct acoustic propagation/radiation and liner modeling tools in the design and evaluation of novel broadband liner concepts for complex engine configurations.

  6. Improving outcomes and lowering costs by applying advanced models of in-home care.

    PubMed

    Boling, Peter A; Chandekar, Rashmi V; Hungate, Beth; Purvis, Martha; Selby-Penczak, Rachel; Abbey, Linda J

    2013-01-01

    With advances in monitoring and telemedicine, the complexity of care administered in the home to properly selected patients can approach that delivered in the hospital. The challenges include making sure that qualified personnel regularly visit the patient at home, both individually and in teams; information is accurately communicated among the caregiver teams across venues and over time; and patients understand the information communicated to them by providers. Despite these challenges, the benefits of treating chronically or terminally ill patients at home are significant. Among the most important are improved patient satisfaction and reduced cost. Numerous studies have shown that most patients prefer to spend their convalescence or their last days at home. The financial benefits of enabling patients to recover or to die at home are significant.

  7. Advanced Physical Models and Numerical Methods for High Enthalpy and Plasma Flows Applied to Hypersonics

    DTIC Science & Technology

    2011-07-28

    models for the noble gases have been detailed which included atom and electron-impact processes as well as radiative processes. These models are...sections using R-matrix calculations for most of the noble gases which agree favorably with the detailed experimental results of Buckmann et al [3...a semi-empirical fit for momentum transfer cross sections involving noble gases, both pure as well as in Atom Polarizability Dipole, αd [a 3

  8. Interactive presurgical simulation applying advanced 3D imaging and modeling techniques for skull base and deep tumors.

    PubMed

    Oishi, Makoto; Fukuda, Masafumi; Yajima, Naoki; Yoshida, Kenzo; Takahashi, Machiko; Hiraishi, Tetsuya; Takao, Tetsuro; Saito, Akihiko; Fujii, Yukihiko

    2013-07-01

    In this paper, the authors' goal was to report their novel presurgical simulation method applying interactive virtual simulation (IVS) using 3D computer graphics (CG) data and microscopic observation of color-printed plaster models based on these CG data in surgery for skull base and deep tumors. For 25 operations in 23 patients with skull base or deep intracranial tumors (meningiomas, schwannomas, epidermoid tumors, chordomas, and others), the authors carried out presurgical simulation based on 3D CG data created by image analysis for radiological data. Interactive virtual simulation was performed by modifying the 3D CG data to imitate various surgical procedures, such as bone drilling, brain retraction, and tumor removal, with manipulation of a haptic device. The authors also produced color-printed plaster models of modified 3D CG data by a selective laser sintering method and observed them under the operative microscope. In all patients, IVS provided detailed and realistic surgical perspectives of sufficient quality, thereby allowing surgeons to determine an appropriate and feasible surgical approach. Surgeons agreed that in 44% of the 25 operations IVS showed high utility (as indicated by a rating of "prominent") in comprehending 3D microsurgical anatomies for which reconstruction using only 2D images was complicated. Microscopic observation of color-printed plaster models in 12 patients provided further utility in confirming realistic surgical anatomies. The authors' presurgical simulation method applying advanced 3D imaging and modeling techniques provided a realistic environment for practicing microsurgical procedures virtually and enabled the authors to ascertain complex microsurgical anatomy, to determine the optimal surgical strategies, and also to efficiently educate neurosurgical trainees, especially during surgery for skull base and deep tumors.

  9. Advancing the Interdisciplinary Collaborative Health Team Model: Applying Democratic Professionalism, Implementation Science, and Therapeutic Alliance to Enact Social Justice Practice.

    PubMed

    Murphy, Nancy

    2015-01-01

    This essay reframes the interdisciplinary collaborative health team model by proposing the application of 3 foundational pillars-democratic professionalism, implementation science, and therapeutic alliance to advance this practice. The aim was to address challenges to the model, enhance their functional capacity, and explicate and enact social justice practices to affect individual health outcomes while simultaneously addressing health inequities. The pillars are described and examples from the author's dissertation research illustrate how the pillars were used to bring about action. Related theories, models, and frameworks that have negotiation, capacity building, collaboration, and knowledge/task/power sharing as central concepts are presented under each of the pillars.

  10. Applied model validation

    NASA Astrophysics Data System (ADS)

    Davies, A. D.

    1985-07-01

    The NBS Center for Fire Research (CFR) conducts scientific research bearing on the fire safety of buildings, vehicles, tunnels and other inhabited structures. Data from controlled fire experiments are collected, analyzed and reduced to the analytical formulas that appear to underly the observed phenomena. These results and more general physical principles are then combined into models to predict the development of environments that may be hostile to humans. This is a progress report of an applied model validation case study. The subject model is Transport of Fire, Smoke and Gases (FAST). Products from a fire in a burn room exit through a connected corridor to outdoors. Cooler counterflow air in a lower layer feeds the fire. The model predicts corridor layer temperatures and thicknesses vs. time, given enclosure, fire and ambient specifications. Data have been collected from 38 tests using several fire sizes, but have not been reduced. Corresponding model results, and model and test documentation are yet to come. Considerable modeling and calculation is needed to convert instrument readings to test results comparable with model outputs so that residual differences may be determined.

  11. Hierarchical Multiscale Framework for Materials Modeling: Advances in Scale-Bridging Applied to a Taylor Anvil Impact Test of RDX

    NASA Astrophysics Data System (ADS)

    Barnes, Brian; Leiter, Kenneth; Becker, Richard; Knap, Jaroslaw; Brennan, John

    As part of a multiscale modeling effort, we present progress on a challenge in continuum-scale modeling: the direct incorporation of complex molecular-level processes in the constitutive evaluation. In this initial phase of the research we use a concurrent scale-bridging approach, with a hierarchical multiscale framework running in parallel to couple a particle-based model (the ''lower scale'') computing the equation of state (EOS) to the constitutive response in a finite-element multi-physics simulation (the ''upper scale''). The lower scale simulations of 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) use a force-matched coarse-grain model and dissipative particle dynamics methods, and the upper scale simulation is of a Taylor anvil impact experiment. Results emphasize use of adaptive sampling (via dynamic kriging) that accelerates time to solution, and its comparison to fully ''on the fly'' runs. Work towards inclusion of a fully reactive EOS is also discussed.

  12. Major advances in applied dairy cattle nutrition.

    PubMed

    Eastridge, M L

    2006-04-01

    Milk yield per cow continues to increase with a slower rate of increase in dry matter intake; thus, efficiency of ruminal fermentation and digestibility of the dietary components are key factors in improving the efficiency of feed use. Over the past 25 yr, at least 2,567 articles relating to ruminant or dairy nutrition have been published in the Journal of Dairy Science. These studies have provided important advancements in improving feed efficiency and animal health by improving quality of feeds, increasing feedstuff and overall diet digestibility, better defining interactions among feedstuffs in diets, identifying alternative feed ingredients, better defining nutrient requirements, and improving efficiency of ruminal fermentation. The publications are vital in continuing to make advancements in providing adequate nutrition to dairy cattle and for facilitating exchange of knowledge among scientists. Forages have been studied more extensively than any other type of feed. Cereal grains continue to be the primary contributors of starch to diets, and thus are very important in meeting the energy needs of dairy cattle. Processing of cereal grains has improved their use. Feeding by-products contributes valuable nutrients to diets and allows feedstuffs to be used that would otherwise be handled as wastes in landfills. Many of these by-products provide a considerable amount of protein, nonforage fiber, fat, and minerals (sometimes a detriment as in the case of P) to diets. The primary feeding system today is the total mixed ration, with still considerable use of the pasture system. Major improvements have occurred in the use of protein, carbohydrates, and fats in diets. Although advancements have been made in feeding practices to minimize the risk of metabolic diseases, the periparturient period continues to present some of the greatest challenges in animal health. Computers are a must today for diet formulation and evaluation, but fewer software programs are developed by

  13. Applied groundwater modeling, 2nd Edition

    USGS Publications Warehouse

    Anderson, Mary P.; Woessner, William W.; Hunt, Randall J.

    2015-01-01

    This second edition is extensively revised throughout with expanded discussion of modeling fundamentals and coverage of advances in model calibration and uncertainty analysis that are revolutionizing the science of groundwater modeling. The text is intended for undergraduate and graduate level courses in applied groundwater modeling and as a comprehensive reference for environmental consultants and scientists/engineers in industry and governmental agencies.

  14. Novel imazethapyr detoxification applying advanced oxidation processes.

    PubMed

    Stathis, Ioannis; Hela, Dimitra G; Scrano, Laura; Lelario, Filomena; Emanuele, Lucia; Bufo, Sabino A

    2011-01-01

    Different degradation methods have been applied to assess the suitability of advanced oxidation process (AOPs) to promote mineralization of imazethapyr [(RS)-5-ethyl-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid], a widely used imidazolinone class herbicide, the persistence of which has been demonstrated in surface and ground waters destined to human uses. Independent of the oxidation process assessed, the decomposition of imazethapyr always followed a pseudo-first order kinetic. The direct UV-irradiation (UV) of the herbicide as well as its oxidation with ozone (O₃), and hydrogen peroxide tied to UV-irradiation (H₂O₂/UV) were sufficiently slow to permit the identification of intermediate products, the formation pathway of which has been proposed. Ozonation joined to UV-irradiation (O₃/UV), ozonation joined to titanium dioxide photo-catalysis (TiO₂/UV+O₃), sole photo-catalysis (TiO₂/UV), and photo-catalysis reinforced with hydrogen peroxide-oxidation (TiO₂/UV+H₂O₂) were characterized by a faster degradation and rapid formation of a lot of small molecules, which were quickly degraded to complete mineralization. The most effective oxidation methods were those using titanium dioxide photo-catalysis enhanced either by ozonation or hydrogen peroxide. Most of all, these last processes were useful to avoid the development of dangerous by-products.

  15. Heuristics Applied in the Development of Advanced Space Mission Concepts

    NASA Technical Reports Server (NTRS)

    Nilsen, Erik N.

    1998-01-01

    Advanced mission studies are the first step in determining the feasibility of a given space exploration concept. A space scientist develops a science goal in the exploration of space. This may be a new observation method, a new instrument or a mission concept to explore a solar system body. In order to determine the feasibility of a deep space mission, a concept study is convened to determine the technology needs and estimated cost of performing that mission. Heuristics are one method of defining viable mission and systems architectures that can be assessed for technology readiness and cost. Developing a viable architecture depends to a large extent upon extending the existing body of knowledge, and applying it in new and novel ways. These heuristics have evolved over time to include methods for estimating technical complexity, technology development, cost modeling and mission risk in the unique context of deep space missions. This paper examines the processes involved in performing these advanced concepts studies, and analyzes the application of heuristics in the development of an advanced in-situ planetary mission. The Venus Surface Sample Return mission study provides a context for the examination of the heuristics applied in the development of the mission and systems architecture. This study is illustrative of the effort involved in the initial assessment of an advance mission concept, and the knowledge and tools that are applied.

  16. Applied Reverberation Modeling Workshop

    DTIC Science & Technology

    2011-09-01

    NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING...Later, Zhou [3] and others extended their work to reverberation. ASPM/ ASTRAL agreed reasonably well with the energy flux model reverberation and...simulation and training requirements. RELATED PROJECTS The ONR-SPAWAR Reverberation Modeling Workshop is a closely related project that was intended

  17. Applied Reverberation Modeling Workshop

    DTIC Science & Technology

    2010-01-01

    Reverberation Modeling Workshop 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f...included both propagation and reverberation with the receiver on a transect perpendicular to the wedge (3-D effects were ignored). The ASTRAL /ASPM...by the PI. The interest was in determining how the operational models ( ASTRAL /ASPM) performed in a sloping environment. ASTRAL is extremely fast

  18. Recent Advances in Nanotechnology Applied to Biosensors

    PubMed Central

    Zhang, Xueqing; Guo, Qin; Cui, Daxiang

    2009-01-01

    In recent years there has been great progress the application of nanomaterials in biosensors. The importance of these to the fundamental development of biosensors has been recognized. In particular, nanomaterials such as gold nanoparticles, carbon nanotubes, magnetic nanoparticles and quantum dots have been being actively investigated for their applications in biosensors, which have become a new interdisciplinary frontier between biological detection and material science. Here we review some of the main advances in this field over the past few years, explore the application prospects, and discuss the issues, approaches, and challenges, with the aim of stimulating a broader interest in developing nanomaterial-based biosensors and improving their applications in disease diagnosis and food safety examination. PMID:22399954

  19. 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.

  20. ADVANCED CHEMISTRY BASINS MODEL

    SciTech Connect

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

    2004-05-01

    The advanced Chemistry Basin Model project has been operative for 48 months. During this period, about half the project tasks are on projected schedule. On average the project is somewhat behind schedule (90%). Unanticipated issues are causing model integration to take longer then scheduled, delaying final debugging and manual development. It is anticipated that a short extension will be required to fulfill all contract obligations.

  1. Airline return-on-investment model for technology evaluation. [computer program to measure economic value of advanced technology applied to passenger aircraft

    NASA Technical Reports Server (NTRS)

    1974-01-01

    This report presents the derivation, description, and operating instructions for a computer program (TEKVAL) which measures the economic value of advanced technology features applied to long range commercial passenger aircraft. The program consists of three modules; and airplane sizing routine, a direct operating cost routine, and an airline return-on-investment routine. These modules are linked such that they may be operated sequentially or individually, with one routine generating the input for the next or with the option of externally specifying the input for either of the economic routines. A very simple airplane sizing technique was previously developed, based on the Brequet range equation. For this program, that sizing technique has been greatly expanded and combined with the formerly separate DOC and ROI programs to produce TEKVAL.

  2. Modeling Applied to Problem Solving

    NASA Astrophysics Data System (ADS)

    Pawl, Andrew; Barrantes, Analia; Pritchard, David E.

    2009-10-01

    Modeling Applied to Problem Solving (MAPS) is a pedagogy that helps students transfer instruction to problem solving in an expert-like manner. Declarative and Procedural syllabus content is organized and learned (not discovered) as a hierarchy of General Models. Students solve problems using an explicit Problem Modeling Rubric that begins with System, Interactions and Model (S.I.M.). System and Interactions are emphasized as the key to a strategic description of the system and the identification of the appropriate General Model to apply to the problem. We have employed the pedagogy in a three-week review course for students who received a D in mechanics. The course was assessed by a final exam retest as well as pre and post C-LASS surveys, yielding a one standard deviation improvement in the students' ability to solve final exam problems and a statistically significant positive shift in 7 of the 9 categories in the C-LASS.

  3. Applied Developmental Science: An Advanced Textbook. The SAGE Program on Applied Developmental Science

    ERIC Educational Resources Information Center

    Lerner, Richard M., Ed.; Jacobs, Fraincine, Ed.; Wertlieb, Donald, Ed.

    2005-01-01

    This course textbook has been adapted from the four-volume "Handbook of Applied Developmental Science" (SAGE 2003), a work that offers a detailed roadmap for action and research in ensuring positive child, youth, and family development. In 20 chapters, "Applied Developmental Science: An Advanced Textbook" brings together theory and application…

  4. Applied Developmental Science: An Advanced Textbook. The SAGE Program on Applied Developmental Science

    ERIC Educational Resources Information Center

    Lerner, Richard M., Ed.; Jacobs, Fraincine, Ed.; Wertlieb, Donald, Ed.

    2005-01-01

    This course textbook has been adapted from the four-volume "Handbook of Applied Developmental Science" (SAGE 2003), a work that offers a detailed roadmap for action and research in ensuring positive child, youth, and family development. In 20 chapters, "Applied Developmental Science: An Advanced Textbook" brings together theory and application…

  5. Modeling Applied to Problem Solving

    NASA Astrophysics Data System (ADS)

    Pawl, Andrew; Barrantes, Analia; Pritchard, David E.

    2009-11-01

    We describe a modeling approach to help students learn expert problem solving. Models are used to present and hierarchically organize the syllabus content and apply it to problem solving, but students do not develop and validate their own Models through guided discovery. Instead, students classify problems under the appropriate instructor-generated Model by selecting a system to consider and describing the interactions that are relevant to that system. We believe that this explicit System, Interactions and Model (S.I.M.) problem modeling strategy represents a key simplification and clarification of the widely disseminated modeling approach originated by Hestenes and collaborators. Our narrower focus allows modeling physics to be integrated into (as opposed to replacing) a typical introductory college mechanics course, while preserving the emphasis on understanding systems and interactions that is the essence of modeling. We have employed the approach in a three-week review course for MIT freshmen who received a D in the fall mechanics course with very encouraging results.

  6. 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.

  7. 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.

  8. Advances in the NASA Earth Science Division Applied Science Program

    NASA Astrophysics Data System (ADS)

    Friedl, L.; Bonniksen, C. K.; Escobar, V. M.

    2016-12-01

    The NASA Earth Science Division's Applied Science Program advances the understanding of and ability to used remote sensing data in support of socio-economic needs. The integration of socio-economic considerations in to NASA Earth Science projects has advanced significantly. The large variety of acquisition methods used has required innovative implementation options. The integration of application themes and the implementation of application science activities in flight project is continuing to evolve. The creation of the recently released Earth Science Division, Directive on Project Applications Program and the addition of an application science requirement in the recent EVM-2 solicitation document NASA's current intent. Continuing improvement in the Earth Science Applications Science Program are expected in the areas of thematic integration, Project Applications Program tailoring for Class D missions and transfer of knowledge between scientists and projects.

  9. Applying Advanced Ground-Based Remote Sensing in the Southeast Asian Maritime Continent to Characterize Regional Proficiencies in Smoke Transport Modeling

    NASA Technical Reports Server (NTRS)

    Campbell, James R.; Ge, Cui; Wang, Jun; Welton, Ellsworth J.; Bucholtz, Anthony; Hyer, Edward J.; Reid, Elizabeth A.; Chew, Boon Ning; Liew, Soo-Chin; Salinas, Santo V.; hide

    2015-01-01

    This work describes some of the most extensive ground-based observations of the aerosol profile collected in Southeast Asia to date, highlighting the challenges in simulating these observations with a mesoscale perspective. An 84-h WRF Model coupled with chemistry (WRF-Chem) mesoscale simulation of smoke particle transport at Kuching, Malaysia, in the southern Maritime Continent of Southeast Asia is evaluated relative to a unique collection of continuous ground-based lidar, sun photometer, and 4-h radiosonde profiling. The period was marked by relatively dry conditions, allowing smoke layers transported to the site unperturbed by wet deposition to be common regionally. The model depiction is reasonable overall. Core thermodynamics, including landsea-breeze structure, are well resolved. Total model smoke extinction and, by proxy, mass concentration are low relative to observation. Smoke emissions source products are likely low because of undersampling of fires in infrared sun-synchronous satellite products, which is exacerbated regionally by endemic low-level cloud cover. Differences are identified between the model mass profile and the lidar profile, particularly during periods of afternoon convective mixing. A static smoke mass injection height parameterized for this study potentially influences this result. The model does not resolve the convective mixing of aerosol particles into the lower free troposphere or the enhancement of near-surface extinction from nighttime cooling and hygroscopic effects.

  10. ADVANCED MIXING MODELS

    SciTech Connect

    Lee, S; Dimenna, R; Tamburello, D

    2011-02-14

    The process of recovering and processing High Level Waste (HLW) the waste in storage tanks at the Savannah River Site (SRS) typically requires mixing the contents of the tank with one to four mixers (pumps) 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 typically 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 focus of the present work is to establish mixing criteria applicable to miscible fluids, with an ultimate goal of addressing waste processing in HLW tanks at SRS and quantifying the mixing time required to suspend sludge particles with the submersible jet pump. A single-phase computational fluid dynamics (CFD) approach was taken for the analysis of jet flow patterns with an emphasis on the velocity decay and the turbulent flow evolution for the farfield region from the pump. Literature results for a turbulent jet flow are reviewed, since the decay of the axial jet velocity and the evolution of the jet flow patterns are important phenomena affecting sludge suspension and mixing operations. The work described in this report suggests a basis for further development of the theory leading to the identified mixing indicators, with benchmark analyses demonstrating their consistency with widely accepted correlations. Although the indicators are somewhat generic in nature, they are applied to Savannah River Site (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

  11. Fracture Toughness of Advanced Structural Ceramics: Applying ASTM C1421

    DOE PAGES

    Swab, Jeffrey J.; Tice, Jason; Wereszczak, Andrew A.; ...

    2014-11-03

    The three methods of determining the quasi-static Mode I fracture toughness (KIc) (surface crack in flexure – SC, single-edge precracked beam – PB, and chevron notched beam – VB) found in ASTM C1421 were applied to a variety of advanced ceramic materials. All three methods produced valid and comparable KIc values for the Al2O3, SiC, Si3N4 and SiAlON ceramics examined. However, not all methods could successfully be applied to B4C, ZrO2 and WC ceramics due to a variety of material factors. The coarse-grained microstructure of one B4C hindered the ability to observe and measure the precracks generated in the SCmore » and PB methods while the transformation toughening in the ZrO2 prevented the formation of the SC and PB precracks and thus made it impossible to use either method on this ceramic. The high strength and elastic modulus of the WC made it impossible to achieve stable crack growth using the VB method because the specimen stored a tremendous amount of energy prior to fracture. Even though these methods have passed the rigors of the standardization process there are still some issues to be resolved when the methods are applied to certain classes of ceramics. We recommend that at least two of these methods be employed to determine the KIc, especially when a new or unfamiliar ceramic is being evaluated.« less

  12. Advances in Molecular Rotational Spectroscopy for Applied Science

    NASA Astrophysics Data System (ADS)

    Harris, Brent; Fields, Shelby S.; Pulliam, Robin; Muckle, Matt; Neill, Justin L.

    2017-06-01

    Advances in chemical sensitivity and robust, solid-state designs for microwave/millimeter-wave instrumentation compel the expansion of molecular rotational spectroscopy as research tool into applied science. It is familiar to consider molecular rotational spectroscopy for air analysis. Those techniques for molecular rotational spectroscopy are included in our presentation of a more broad application space for materials analysis using Fourier Transform Molecular Rotational Resonance (FT-MRR) spectrometers. There are potentially transformative advantages for direct gas analysis of complex mixtures, determination of unknown evolved gases with parts per trillion detection limits in solid materials, and unambiguous chiral determination. The introduction of FT-MRR as an alternative detection principle for analytical chemistry has created a ripe research space for the development of new analytical methods and sampling equipment to fully enable FT-MRR. We present the current state of purpose-built FT-MRR instrumentation and the latest application measurements that make use of new sampling methods.

  13. Recent advances in click chemistry applied to dendrimer synthesis.

    PubMed

    Arseneault, Mathieu; Wafer, Caroline; Morin, Jean-François

    2015-05-20

    Dendrimers are monodisperse polymers grown in a fractal manner from a central point. They are poised to become the cornerstone of nanoscale devices in several fields, ranging from biomedicine to light-harvesting. Technical difficulties in obtaining these molecules has slowed their transfer from academia to industry. In 2001, the arrival of the "click chemistry" concept gave the field a major boost. The flagship reaction, a modified Hüisgen cycloaddition, allowed researchers greater freedom in designing and building dendrimers. In the last five years, advances in click chemistry saw a wider use of other click reactions and a notable increase in the complexity of the reported structures. This review covers key developments in the click chemistry field applied to dendrimer synthesis from 2010 to 2015. Even though this is an expert review, basic notions and references have been included to help newcomers to the field.

  14. 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.

  15. 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

  16. Fracture Toughness of Advanced Structural Ceramics: Applying ASTM C1421

    SciTech Connect

    Swab, Jeffrey J.; Tice, Jason; Wereszczak, Andrew A.; Kraft, Reuben H.

    2014-11-03

    The three methods of determining the quasi-static Mode I fracture toughness (KIc) (surface crack in flexure – SC, single-edge precracked beam – PB, and chevron notched beam – VB) found in ASTM C1421 were applied to a variety of advanced ceramic materials. All three methods produced valid and comparable KIc values for the Al2O3, SiC, Si3N4 and SiAlON ceramics examined. However, not all methods could successfully be applied to B4C, ZrO2 and WC ceramics due to a variety of material factors. The coarse-grained microstructure of one B4C hindered the ability to observe and measure the precracks generated in the SC and PB methods while the transformation toughening in the ZrO2 prevented the formation of the SC and PB precracks and thus made it impossible to use either method on this ceramic. The high strength and elastic modulus of the WC made it impossible to achieve stable crack growth using the VB method because the specimen stored a tremendous amount of energy prior to fracture. Even though these methods have passed the rigors of the standardization process there are still some issues to be resolved when the methods are applied to certain classes of ceramics. We recommend that at least two of these methods be employed to determine the KIc, especially when a new or unfamiliar ceramic is being evaluated.

  17. Applied and Workforce Baccalaureate Models

    ERIC Educational Resources Information Center

    Floyd, Deborah L.; Falconetti, Angela M. Garcia; Felsher, Rivka A.

    2012-01-01

    Community colleges have a storied history of successfully providing pathways and access to credentials and degrees through various models of delivery and in diverse programs of study. Until recently, the highest degree offered by community colleges was the associate degree. During the past decade, major changes have occurred in the landscape of…

  18. Applied and Workforce Baccalaureate Models

    ERIC Educational Resources Information Center

    Floyd, Deborah L.; Falconetti, Angela M. Garcia; Felsher, Rivka A.

    2012-01-01

    Community colleges have a storied history of successfully providing pathways and access to credentials and degrees through various models of delivery and in diverse programs of study. Until recently, the highest degree offered by community colleges was the associate degree. During the past decade, major changes have occurred in the landscape of…

  19. Advanced Cumulative Damage Modeling

    DTIC Science & Technology

    1988-09-01

    MPaim and (b) 31 MPa/ m . xiv 5.42 Results of the Constant AK hold time tests on Alloy 718 at 132 593"C with (a) R-O.O, (b) R-0.5, and (c) R-0.8. 5.43...this type of model is the relationship first proposed by Walker( 40) Keff - Kmax (-R) m (2.14) where m is known as the Walker exponent Vhen m is zpro...Ketf zqual’ KraA: but when m i ut,!Lty, KeZf cqualb AK In reality, the Walker exponent is an empirical factor which accounts for mean stress and

  20. Advanced deformation process modeling

    SciTech Connect

    Kocks, U.F.; Embury, J.D.; Beaudoin, A.J.; Dawson, P.R.; MacEwen, S.R.; Mecking, H.J.

    1997-08-01

    Progress was made in achieving a comprehensive and coherent description of material behavior in deformation processing. The materials included were metals, alloys, intermetallic compounds, arbitrary lattice structure, and metal matrix composites. Aspects of behavior modeled included kinetics of flow and strain hardening, as well as recrystallization and the various anisotropies of strength and compliance. Highlights include a new prediction of the limiting strength of materials at high temperature, a new understanding of the generation of new grain boundaries during forming operations, and a quantitatively verified computer simulation of texture development and the resulting behavioral anisotropies.

  1. Ecological modeling for applied science

    NASA Astrophysics Data System (ADS)

    Melton, Forrest; Lobitz, Brad; Turner, Woody; Sheffner, Edwin; Haynes, John

    Ecological modeling is becoming an increasingly important tool for uniting biological observations with remote sensing and ground-based data networks to develop predictive tools for resource management and human health.The availability of over three petabytes of data from the NASA Earth Observing System Data and Information System (EOSDIS) alone provides an unprecedented opportunity to develop Earth science applications for decision support. In combination with data networks such as the U.S. National Oceanic and Atmospheric Administration's National Climate Data Center, the nonprofit NatureServe's network of biological inventories, the National Environmental Public Health Tracking Network of the U.S. Centers for Disease Control and Prevention, and many others, there is a vast wealth of Earth observation data on parameters as diverse as land cover, sea surface temperature, precipitation, species distribution, and disease occurrence.

  2. Applied Creativity: The Creative Marketing Breakthrough Model

    ERIC Educational Resources Information Center

    Titus, Philip A.

    2007-01-01

    Despite the increasing importance of personal creativity in today's business environment, few conceptual creativity frameworks have been presented in the marketing education literature. The purpose of this article is to advance the integration of creativity instruction into marketing classrooms by presenting an applied creative marketing…

  3. Advancing MODFLOW Applying the Derived Vector Space Method

    NASA Astrophysics Data System (ADS)

    Herrera, G. S.; Herrera, I.; Lemus-García, M.; Hernandez-Garcia, G. D.

    2015-12-01

    The most effective domain decomposition methods (DDM) are non-overlapping DDMs. Recently a new approach, the DVS-framework, based on an innovative discretization method that uses a non-overlapping system of nodes (the derived-nodes), was introduced and developed by I. Herrera et al. [1, 2]. Using the DVS-approach a group of four algorithms, referred to as the 'DVS-algorithms', which fulfill the DDM-paradigm (i.e. the solution of global problems is obtained by resolution of local problems exclusively) has been derived. Such procedures are applicable to any boundary-value problem, or system of such equations, for which a standard discretization method is available and then software with a high degree of parallelization can be constructed. In a parallel talk, in this AGU Fall Meeting, Ismael Herrera will introduce the general DVS methodology. The application of the DVS-algorithms has been demonstrated in the solution of several boundary values problems of interest in Geophysics. Numerical examples for a single-equation, for the cases of symmetric, non-symmetric and indefinite problems were demonstrated before [1,2]. For these problems DVS-algorithms exhibited significantly improved numerical performance with respect to standard versions of DDM algorithms. In view of these results our research group is in the process of applying the DVS method to a widely used simulator for the first time, here we present the advances of the application of this method for the parallelization of MODFLOW. Efficiency results for a group of tests will be presented. References [1] I. Herrera, L.M. de la Cruz and A. Rosas-Medina. Non overlapping discretization methods for partial differential equations, Numer Meth Part D E, (2013). [2] Herrera, I., & Contreras Iván "An Innovative Tool for Effectively Applying Highly Parallelized Software To Problems of Elasticity". Geofísica Internacional, 2015 (In press)

  4. Advanced Background Subtraction Applied to Aeroacoustic Wind Tunnel Testing

    NASA Technical Reports Server (NTRS)

    Bahr, Christopher J.; Horne, William C.

    2015-01-01

    An advanced form of background subtraction is presented and applied to aeroacoustic wind tunnel data. A variant of this method has seen use in other fields such as climatology and medical imaging. The technique, based on an eigenvalue decomposition of the background noise cross-spectral matrix, is robust against situations where isolated background auto-spectral levels are measured to be higher than levels of combined source and background signals. It also provides an alternate estimate of the cross-spectrum, which previously might have poor definition for low signal-to-noise ratio measurements. Simulated results indicate similar performance to conventional background subtraction when the subtracted spectra are weaker than the true contaminating background levels. Superior performance is observed when the subtracted spectra are stronger than the true contaminating background levels. Experimental results show limited success in recovering signal behavior for data where conventional background subtraction fails. They also demonstrate the new subtraction technique's ability to maintain a proper coherence relationship in the modified cross-spectral matrix. Beam-forming and de-convolution results indicate the method can successfully separate sources. Results also show a reduced need for the use of diagonal removal in phased array processing, at least for the limited data sets considered.

  5. 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

  6. Applying Technology Ranking and Systems Engineering in Advanced Life Support

    NASA Technical Reports Server (NTRS)

    Jones, Harry; Luna, Bernadette (Technical Monitor)

    2000-01-01

    According to the Advanced Life Support (ALS) Program Plan, the Systems Modeling and Analysis Project (SMAP) has two important tasks: 1) prioritizing investments in ALS Research and Technology Development (R&TD), and 2) guiding the evolution of ALS systems. Investments could be prioritized simply by independently ranking different technologies, but we should also consider a technology's impact on system design. Guiding future ALS systems will require SMAP to consider many aspects of systems engineering. R&TD investments can be prioritized using familiar methods for ranking technology. The first step is gathering data on technology performance, safety, readiness level, and cost. Then the technologies are ranked using metrics or by decision analysis using net present economic value. The R&TD portfolio can be optimized to provide the maximum expected payoff in the face of uncertain future events. But more is needed. The optimum ALS system can not be designed simply by selecting the best technology for each predefined subsystem. Incorporating a new technology, such as food plants, can change the specifications of other subsystems, such as air regeneration. Systems must be designed top-down starting from system objectives, not bottom-up from selected technologies. The familiar top-down systems engineering process includes defining mission objectives, mission design, system specification, technology analysis, preliminary design, and detail design. Technology selection is only one part of systems analysis and engineering, and it is strongly related to the subsystem definitions. ALS systems should be designed using top-down systems engineering. R&TD technology selection should consider how the technology affects ALS system design. Technology ranking is useful but it is only a small part of systems engineering.

  7. Applying Technology Ranking and Systems Engineering in Advanced Life Support

    NASA Technical Reports Server (NTRS)

    Jones, Harry; Luna, Bernadette (Technical Monitor)

    2000-01-01

    According to the Advanced Life Support (ALS) Program Plan, the Systems Modeling and Analysis Project (SMAP) has two important tasks: 1) prioritizing investments in ALS Research and Technology Development (R&TD), and 2) guiding the evolution of ALS systems. Investments could be prioritized simply by independently ranking different technologies, but we should also consider a technology's impact on system design. Guiding future ALS systems will require SMAP to consider many aspects of systems engineering. R&TD investments can be prioritized using familiar methods for ranking technology. The first step is gathering data on technology performance, safety, readiness level, and cost. Then the technologies are ranked using metrics or by decision analysis using net present economic value. The R&TD portfolio can be optimized to provide the maximum expected payoff in the face of uncertain future events. But more is needed. The optimum ALS system can not be designed simply by selecting the best technology for each predefined subsystem. Incorporating a new technology, such as food plants, can change the specifications of other subsystems, such as air regeneration. Systems must be designed top-down starting from system objectives, not bottom-up from selected technologies. The familiar top-down systems engineering process includes defining mission objectives, mission design, system specification, technology analysis, preliminary design, and detail design. Technology selection is only one part of systems analysis and engineering, and it is strongly related to the subsystem definitions. ALS systems should be designed using top-down systems engineering. R&TD technology selection should consider how the technology affects ALS system design. Technology ranking is useful but it is only a small part of systems engineering.

  8. Improving and applying Lagrangian models of the atmosphere

    NASA Astrophysics Data System (ADS)

    Lin, John C.; Brunner, Dominik; Gerbig, Christoph

    2012-01-01

    AGU Chapman Conference on Advances in Lagrangian Modeling of the Atmosphere; Grindelwald, Switzerland, 10-14 October 2011 Under the majestic gaze of the Eiger north face in Switzerland, an international group of researchers met as part of a Chapman Conference to discuss advances in Lagrangian modeling of the atmosphere. Lagrangian models track the movement of air parcels, giving rise to trajectory information and source/receptor linkages that have become increasingly popular as tools used by geoscientists. The conference was an opportunity for a diverse group of researchers developing and applying Lagrangian models to congregate and discuss the use of such models to understand geophysical phenomena and to identify how to further improve the models. The 98 participants (of which 17 were graduate students) hailed from 19 countries around the world.

  9. Recent advances in atomic modeling

    SciTech Connect

    Goldstein, W.H.

    1988-10-12

    Precision spectroscopy of solar plasmas has historically been the goad for advances in calculating the atomic physics and dynamics of highly ionized atoms. Recent efforts to understand the laboratory plasmas associated with magnetic and inertial confinement fusion, and with X-ray laser research, have played a similar role. Developments spurred by laboratory plasma research are applicable to the modeling of high-resolution spectra from both solar and cosmic X-ray sources, such as the photoionized plasmas associated with accretion disks. Three of these developments in large scale atomic modeling are reviewed: a new method for calculating large arrays of collisional excitation rates, a sum rule based method for extending collisional-radiative models and modeling the effects of autoionizing resonances, and a detailed level accounting calculation of resonant excitation rates in FeXVII. 21 refs., 5 figs., 2 tabs.

  10. 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.

  11. Advanced Signal Processing Methods Applied to Digital Mammography

    NASA Technical Reports Server (NTRS)

    Stauduhar, Richard P.

    1997-01-01

    without further support. Task 5: Better modeling does indeed make an improvement in the detection output. After the proposal ended, we came up with some new theoretical explanations that helps in understanding when the D4 filter should be better. This work is currently in the review process. Task 6: N/A. This no longer applies in view of Tasks 4-5. Task 7: Comprehensive plans for further work have been completed. These plans are the subject of two proposals, one to NASA and one to HHS. These proposals represent plans for a complete evaluation of the methods for identifying normal mammograms, augmented with significant further theoretical work.

  12. 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.

  13. Economic impact of applying advanced technologies to transport airplanes.

    NASA Technical Reports Server (NTRS)

    Carline, A. J. K.

    1972-01-01

    Various technologies have been studied which could have application to the design of future transport airplanes. These technologies include the use of supercritical aerodynamics, composite materials, and active control systems, together with advanced engine designs that provide lower noise and pollutant levels. The economic impact of each technology is shown for a typical fleet of 195-passenger, transcontinental commercial transports cruising at both 0.9M and 0.98M. Comparisons are made with conventional transports cruising at 0.82M. Effects of combining the technologies are discussed. An R & D program aimed at bringing the technologies to fruition is outlined.

  14. Economic impact of applying advanced technologies to transport airplanes.

    NASA Technical Reports Server (NTRS)

    Carline, A. J. K.

    1972-01-01

    Various technologies have been studied which could have application to the design of future transport airplanes. These technologies include the use of supercritical aerodynamics, composite materials, and active control systems, together with advanced engine designs that provide lower noise and pollutant levels. The economic impact of each technology is shown for a typical fleet of 195-passenger, transcontinental commercial transports cruising at both 0.9M and 0.98M. Comparisons are made with conventional transports cruising at 0.82M. Effects of combining the technologies are discussed. An R & D program aimed at bringing the technologies to fruition is outlined.

  15. Advances in urban climate modeling.

    PubMed

    Hidalgo, Julia; Masson, Valéry; Baklanov, Alexander; Pigeon, Grégoire; Gimeno, Luis

    2008-12-01

    Cities interact with the atmosphere over a wide range of scales from the large-scale processes, which have a direct impact on global climate change, to smaller scales, ranging from the conurbation itself to individual buildings. The review presented in this paper analyzes some of the ways in which cities influence atmospheric thermodynamics and airborne pollutant transport. We present the main physical processes that characterize the urban local meteorology (the urban microclimate) and air pollution. We focus on small-scale impacts, including the urban heat island and its causes. The impact on the lower atmosphere over conurbations, air pollution in cities, and the effect on meteorological processes are discussed. An overview of the recent principal advances in urban climatology and air quality modeling in atmospheric numerical models is also presented.

  16. Recent advances of flow cytometry in fundamental and applied microbiology.

    PubMed

    Fouchet, P; Jayat, C; Héchard, Y; Ratinaud, M H; Frelat, G

    1993-01-01

    This review focuses on the recent applications of flow cytometry (FCM) in microbiological research (1987-mid 1992). It tries to give a scope of the important breakthroughs which occurred in this field during this period. The technical difficulties of microorganism analysis by flow cytometry is briefly appraised. The significance and the limits of the different microbial cell parameters attainable by flow analyses are systematically evaluated: light scatter for cell size and structure, fluorescence measurements for quantification of cellular components, microbial antigen detection and cell physiological activity estimation. Emphasis is given on the new technological advances which appeared in the last two years. The second part of the review is devoted to the analysis of the usefulness of flow cytometric approach in the different fields of microbiology: fundamental studies in microbial physiology, differentiation, microbial ecology and aquatic sciences, medical microbiology, parasitology, microbial pharmacology and biotechnology.

  17. AN INTERACTION MODEL APPLIED TO SUPERVISION.

    ERIC Educational Resources Information Center

    BOYD, ROBERT D.

    THIS STUDY OUTLINES A SMALL GROUP INTERACTION MODEL WHICH CAN BE APPLIED TO SUPERVISION. IT CONSISTS OF THREE CHANNELS -- (1) THE MOTIVATIONAL CHANNEL IN WHICH THE MOTIVATIONAL ASPECT OF AN UTTERANCE (I.E. QUESTIONS, EXCLAMATIONS, ASSERTIONS) IS IDENTIFIED ACCORDING TO THE PARTICULAR EGO CRISIS (TRUST VS. MISTRUST, AUTONOMY VS. SHAME DOUBT,…

  18. Linear mixing model applied to coarse resolution satellite data

    NASA Technical Reports Server (NTRS)

    Holben, Brent N.; Shimabukuro, Yosio E.

    1992-01-01

    A linear mixing model typically applied to high resolution data such as Airborne Visible/Infrared Imaging Spectrometer, Thematic Mapper, and Multispectral Scanner System is applied to the NOAA Advanced Very High Resolution Radiometer coarse resolution satellite data. The reflective portion extracted from the middle IR channel 3 (3.55 - 3.93 microns) is used with channels 1 (0.58 - 0.68 microns) and 2 (0.725 - 1.1 microns) to run the Constrained Least Squares model to generate fraction images for an area in the west central region of Brazil. The derived fraction images are compared with an unsupervised classification and the fraction images derived from Landsat TM data acquired in the same day. In addition, the relationship betweeen these fraction images and the well known NDVI images are presented. The results show the great potential of the unmixing techniques for applying to coarse resolution data for global studies.

  19. AN ADVANCED TOOL FOR APPLIED INTEGRATED SAFETY MANAGEMENT

    SciTech Connect

    Potts, T. Todd; Hylko, James M.; Douglas, Terence A.

    2003-02-27

    WESKEM, LLC's Environmental, Safety and Health (ES&H) Department had previously assessed that a lack of consistency, poor communication and using antiquated communication tools could result in varying operating practices, as well as a failure to capture and disseminate appropriate Integrated Safety Management (ISM) information. To address these issues, the ES&H Department established an Activity Hazard Review (AHR)/Activity Hazard Analysis (AHA) process for systematically identifying, assessing, and controlling hazards associated with project work activities during work planning and execution. Depending on the scope of a project, information from field walkdowns and table-top meetings are collected on an AHR form. The AHA then documents the potential failure and consequence scenarios for a particular hazard. Also, the AHA recommends whether the type of mitigation appears appropriate or whether additional controls should be implemented. Since the application is web based, the information is captured into a single system and organized according to the >200 work activities already recorded in the database. Using the streamlined AHA method improved cycle time from over four hours to an average of one hour, allowing more time to analyze unique hazards and develop appropriate controls. Also, the enhanced configuration control created a readily available AHA library to research and utilize along with standardizing hazard analysis and control selection across four separate work sites located in Kentucky and Tennessee. The AHR/AHA system provides an applied example of how the ISM concept evolved into a standardized field-deployed tool yielding considerable efficiency gains in project planning and resource utilization. Employee safety is preserved through detailed planning that now requires only a portion of the time previously necessary. The available resources can then be applied to implementing appropriate engineering, administrative and personal protective equipment

  20. Advances in parameter estimation techniques applied to flexible structures

    NASA Technical Reports Server (NTRS)

    Maben, Egbert; Zimmerman, David C.

    1994-01-01

    In this work, various parameter estimation techniques are investigated in the context of structural system identification utilizing distributed parameter models and 'measured' time-domain data. Distributed parameter models are formulated using the PDEMOD software developed by Taylor. Enhancements made to PDEMOD for this work include the following: (1) a Wittrick-Williams based root solving algorithm; (2) a time simulation capability; and (3) various parameter estimation algorithms. The parameter estimations schemes will be contrasted using the NASA Mini-Mast as the focus structure.

  1. Fatigue models for applied research in warfighting.

    PubMed

    Hursh, Steven R; Redmond, Daniel P; Johnson, Michael L; Thorne, David R; Belenky, Gregory; Balkin, Thomas J; Storm, William F; Miller, James C; Eddy, Douglas R

    2004-03-01

    The U.S. Department of Defense (DOD) has long pursued applied research concerning fatigue in sustained and continuous military operations. In 1996, Hursh developed a simple homeostatic fatigue model and programmed the model into an actigraph to give a continuous indication of performance. Based on this initial work, the Army conducted a study of 1 wk of restricted sleep in 66 subjects with multiple measures of performance, termed the Sleep Dose-Response Study (SDR). This study provided numerical estimation of parameters for the Walter Reed Army Institute of Research Sleep Performance Model (SPM) and elucidated the relationships among several sleep-related performance measures. Concurrently, Hursh extended the original actigraph modeling structure and software expressions for use in other practical applications. The model became known as the Sleep, Activity, Fatigue, and Task Effectiveness (SAFTE) Model, and Hursh has applied it in the construction of a Fatigue Avoidance Scheduling Tool. This software is designed to help optimize the operational management of aviation ground and flight crews, but is not limited to that application. This paper describes the working fatigue model as it is being developed by the DOD laboratories, using the conceptual framework, vernacular, and notation of the SAFTE Model. At specific points where the SPM may differ from SAFTE, this is discussed. Extensions of the SAFTE Model to incorporate dynamic phase adjustment for both transmeridian relocation and shift work are described. The unexpected persistence of performance effects following chronic sleep restriction found in the SDR study necessitated some revisions of the SAFTE Model that are also described. The paper concludes with a discussion of several important modeling issues that remain to be addressed.

  2. Advanced imaging systems for diagnostic investigations applied to Cultural Heritage

    NASA Astrophysics Data System (ADS)

    Peccenini, E.; Albertin, F.; Bettuzzi, M.; Brancaccio, R.; Casali, F.; Morigi, M. P.; Petrucci, F.

    2014-12-01

    The diagnostic investigations are an important resource in the studies on Cultural Heritage to enhance the knowledge on execution techniques, materials and conservation status of a work of art. In this field, due to the great historical and artistic value of the objects, preservation is the main concern; for this reason, new technological equipment has been designed and developed in the Physics Departments of the Universities of Ferrara and Bologna to enhance the non-invasive approach to the study of pictorial artworks and other objects of cultural interest. Infrared (IR) reflectography, X-ray radiography and computed tomography (CT), applied to works of art, are joined by the same goal: to get hidden information on execution techniques and inner structure pursuing the non-invasiveness of the methods, although using different setup and physical principles. In this work transportable imaging systems to investigate large objects in museums and galleries are presented. In particular, 2D scanning devices for IR reflectography and X-ray radiography, CT systems and some applications to the Cultural Heritage are described.

  3. Long Range Strategic Planning. An Applied Model.

    DTIC Science & Technology

    1983-06-01

    relations . Chapter Six is a case study of South African Nuclear Capabilities. 1...Five apply this model to U.S./South African relations . Chapter six is a case study of South African Nuclear Capabilities. ; * ’*’ >• Accession For...invest overseas, the impact of international cartels and access to foreign sources of oil and minerals. : « 9 3. Favorable world order: this

  4. Applying incentive sensitization models to behavioral addiction.

    PubMed

    Rømer Thomsen, Kristine; Fjorback, Lone O; Møller, Arne; Lou, Hans C

    2014-09-01

    The incentive sensitization theory is a promising model for understanding the mechanisms underlying drug addiction, and has received support in animal and human studies. So far the theory has not been applied to the case of behavioral addictions like Gambling Disorder, despite sharing clinical symptoms and underlying neurobiology. We examine the relevance of this theory for Gambling Disorder and point to predictions for future studies. The theory promises a significant contribution to the understanding of behavioral addiction and opens new avenues for treatment.

  5. 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.

  6. Recent advances in applying decision science to managing national forests

    USGS Publications Warehouse

    Marcot, Bruce G.; Thompson, Matthew P.; Runge, Michael C.; Thompson, Frank R.; McNulty, Steven; Cleaves, David; Tomosy, Monica; Fisher, Larry A.; Andrew, Bliss

    2012-01-01

    Management of federal public forests to meet sustainability goals and multiple use regulations is an immense challenge. To succeed, we suggest use of formal decision science procedures and tools in the context of structured decision making (SDM). SDM entails four stages: problem structuring (framing the problem and defining objectives and evaluation criteria), problem analysis (defining alternatives, evaluating likely consequences, identifying key uncertainties, and analyzing tradeoffs), decision point (identifying the preferred alternative), and implementation and monitoring the preferred alternative with adaptive management feedbacks. We list a wide array of models, techniques, and tools available for each stage, and provide three case studies of their selected use in National Forest land management and project plans. Successful use of SDM involves participation by decision-makers, analysts, scientists, and stakeholders. We suggest specific areas for training and instituting SDM to foster transparency, rigor, clarity, and inclusiveness in formal decision processes regarding management of national forests.

  7. 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.

  8. [Advances of NIR spectroscopy technology applied in seed quality detection].

    PubMed

    Zhu, Li-wei; Ma, Wen-guang; Hu, Jin; Zheng, Yun-ye; Tian, Yi-xin; Guan, Ya-jing; Hu, Wei-min

    2015-02-01

    Near infrared spectroscopy (NIRS) technology developed fast in recent years, due to its rapid speed, less pollution, high-efficiency and other advantages. It has been widely used in many fields such as food, chemical industry, pharmacy, agriculture and so on. The seed is the most basic and important agricultural capital goods, and seed quality is important for agricultural production. Most methods presently used for seed quality detecting were destructive, slow and needed pretreatment, therefore, developing one kind of method that is simple and rapid has great significance for seed quality testing. This article reviewed the application and trends of NIRS technology in testing of seed constituents, vigor, disease and insect pests etc. For moisture, starch, protein, fatty acid and carotene content, the model identification rates were high as their relative contents were high; for trace organic, the identification rates were low as their relative content were low. The heat-damaged seeds with low vigor were discriminated by NIRS, the seeds stored for different time could also been identified. The discrimination of frost-damaged seeds was impossible. The NIRS could be used to identify health and infected disease seeds, and did the classification for the health degree; it could identify parts of the fungal pathogens. The NIRS could identify worm-eaten and health seeds, and further distinguished the insect species, however the identification effects for small larval and low injury level of insect pests was not good enough. Finally, in present paper existing problems and development trends for NIRS in seed quality detection was discussed, especially the single seed detecting technology which was characteristic of the seed industry, the standardization of its spectral acquisition accessories will greatly improve its applicability.

  9. Probabilistic Analysis Techniques Applied to Complex Spacecraft Power System Modeling

    NASA Technical Reports Server (NTRS)

    Hojnicki, Jeffrey S.; Rusick, Jeffrey J.

    2005-01-01

    Electric power system performance predictions are critical to spacecraft, such as the International Space Station (ISS), to ensure that sufficient power is available to support all the spacecraft s power needs. In the case of the ISS power system, analyses to date have been deterministic, meaning that each analysis produces a single-valued result for power capability because of the complexity and large size of the model. As a result, the deterministic ISS analyses did not account for the sensitivity of the power capability to uncertainties in model input variables. Over the last 10 years, the NASA Glenn Research Center has developed advanced, computationally fast, probabilistic analysis techniques and successfully applied them to large (thousands of nodes) complex structural analysis models. These same techniques were recently applied to large, complex ISS power system models. This new application enables probabilistic power analyses that account for input uncertainties and produce results that include variations caused by these uncertainties. Specifically, N&R Engineering, under contract to NASA, integrated these advanced probabilistic techniques with Glenn s internationally recognized ISS power system model, System Power Analysis for Capability Evaluation (SPACE).

  10. Probabilistic Analysis Techniques Applied to Complex Spacecraft Power System Modeling

    NASA Technical Reports Server (NTRS)

    Hojnicki, Jeffrey S.; Rusick, Jeffrey J.

    2005-01-01

    Electric power system performance predictions are critical to spacecraft, such as the International Space Station (ISS), to ensure that sufficient power is available to support all the spacecraft s power needs. In the case of the ISS power system, analyses to date have been deterministic, meaning that each analysis produces a single-valued result for power capability because of the complexity and large size of the model. As a result, the deterministic ISS analyses did not account for the sensitivity of the power capability to uncertainties in model input variables. Over the last 10 years, the NASA Glenn Research Center has developed advanced, computationally fast, probabilistic analysis techniques and successfully applied them to large (thousands of nodes) complex structural analysis models. These same techniques were recently applied to large, complex ISS power system models. This new application enables probabilistic power analyses that account for input uncertainties and produce results that include variations caused by these uncertainties. Specifically, N&R Engineering, under contract to NASA, integrated these advanced probabilistic techniques with Glenn s internationally recognized ISS power system model, System Power Analysis for Capability Evaluation (SPACE).

  11. Improved Broadband Liner Optimization Applied to the Advanced Noise Control Fan

    NASA Technical Reports Server (NTRS)

    Nark, Douglas M.; Jones, Michael G.; Sutliff, Daniel L.; Ayle, Earl; Ichihashi, Fumitaka

    2014-01-01

    The broadband component of fan noise has grown in relevance with the utilization of increased bypass ratio and advanced fan designs. Thus, while the attenuation of fan tones remains paramount, the ability to simultaneously reduce broadband fan noise levels has become more desirable. This paper describes improvements to a previously established broadband acoustic liner optimization process using the Advanced Noise Control Fan rig as a demonstrator. Specifically, in-duct attenuation predictions with a statistical source model are used to obtain optimum impedance spectra over the conditions of interest. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners aimed at producing impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increased weighting to specific frequencies and/or operating conditions. Constant-depth, double-degree of freedom and variable-depth, multi-degree of freedom designs are carried through design, fabrication, and testing to validate the efficacy of the design process. Results illustrate the value of the design process in concurrently evaluating the relative costs/benefits of these liner designs. This study also provides an application for demonstrating the integrated use of duct acoustic propagation/radiation and liner modeling tools in the design and evaluation of novel broadband liner concepts for complex engine configurations.

  12. The Influence of Applied STEM Coursetaking on Advanced Mathematics and Science Coursetaking

    ERIC Educational Resources Information Center

    Gottfried, Michael A.

    2015-01-01

    Advanced mathematics and science course taking is critical in building the foundation for students to advance through the STEM pathway-from high school to college to career. To invigorate students' persistence in STEM fields, high schools have been introducing applied STEM courses into the curriculum as a way to reinforce concepts learned in…

  13. 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.

  14. Applying target shadow models for SAR ATR

    NASA Astrophysics Data System (ADS)

    Papson, Scott; Narayanan, Ram M.

    2007-04-01

    Recent work has suggested that target shadows in synthetic aperture radar (SAR) images can be used effectively to aid in target classification. The method outlined in this paper has four steps - segmentation, representation, modeling, and selection. Segmentation is the process by which a smooth, background-free representation of the target's shadow is extracted from an image chip. A chain code technique is then used to represent the shadow boundary. Hidden Markov modeling is applied to sets of chain codes for multiple targets to create a suitable bank of target representations. Finally, an ensemble framework is proposed for classification. The proposed model selection process searches for an optimal ensemble of models based on various target model configurations. A five target subset of the MSTAR database is used for testing. Since the shadow is a back-projection of the target profile, some aspect angles will contain more discriminatory information then others. Therefore, performance is investigated as a function of aspect angle. Additionally, the case of multiple target looks is considered. The capability of the shadow-only classifier to enhance more traditional classification techniques is examined.

  15. Integrated Modeling Program, Applied Chemical Theory (IMPACT)

    PubMed Central

    BANKS, JAY L.; BEARD, HEGE S.; CAO, YIXIANG; CHO, ART E.; DAMM, WOLFGANG; FARID, RAMY; FELTS, ANTHONY K.; HALGREN, THOMAS A.; MAINZ, DANIEL T.; MAPLE, JON R.; MURPHY, ROBERT; PHILIPP, DEAN M.; REPASKY, MATTHEW P.; ZHANG, LINDA Y.; BERNE, BRUCE J.; FRIESNER, RICHARD A.; GALLICCHIO, EMILIO; LEVY, RONALD M.

    2009-01-01

    We provide an overview of the IMPACT molecular mechanics program with an emphasis on recent developments and a description of its current functionality. With respect to core molecular mechanics technologies we include a status report for the fixed charge and polarizable force fields that can be used with the program and illustrate how the force fields, when used together with new atom typing and parameter assignment modules, have greatly expanded the coverage of organic compounds and medicinally relevant ligands. As we discuss in this review, explicit solvent simulations have been used to guide our design of implicit solvent models based on the generalized Born framework and a novel nonpolar estimator that have recently been incorporated into the program. With IMPACT it is possible to use several different advanced conformational sampling algorithms based on combining features of molecular dynamics and Monte Carlo simulations. The program includes two specialized molecular mechanics modules: Glide, a high-throughput docking program, and QSite, a mixed quantum mechanics/molecular mechanics module. These modules employ the IMPACT infrastructure as a starting point for the construction of the protein model and assignment of molecular mechanics parameters, but have then been developed to meet specialized objectives with respect to sampling and the energy function. PMID:16211539

  16. Integrated Modeling Program, Applied Chemical Theory (IMPACT).

    PubMed

    Banks, Jay L; Beard, Hege S; Cao, Yixiang; Cho, Art E; Damm, Wolfgang; Farid, Ramy; Felts, Anthony K; Halgren, Thomas A; Mainz, Daniel T; Maple, Jon R; Murphy, Robert; Philipp, Dean M; Repasky, Matthew P; Zhang, Linda Y; Berne, Bruce J; Friesner, Richard A; Gallicchio, Emilio; Levy, Ronald M

    2005-12-01

    We provide an overview of the IMPACT molecular mechanics program with an emphasis on recent developments and a description of its current functionality. With respect to core molecular mechanics technologies we include a status report for the fixed charge and polarizable force fields that can be used with the program and illustrate how the force fields, when used together with new atom typing and parameter assignment modules, have greatly expanded the coverage of organic compounds and medicinally relevant ligands. As we discuss in this review, explicit solvent simulations have been used to guide our design of implicit solvent models based on the generalized Born framework and a novel nonpolar estimator that have recently been incorporated into the program. With IMPACT it is possible to use several different advanced conformational sampling algorithms based on combining features of molecular dynamics and Monte Carlo simulations. The program includes two specialized molecular mechanics modules: Glide, a high-throughput docking program, and QSite, a mixed quantum mechanics/molecular mechanics module. These modules employ the IMPACT infrastructure as a starting point for the construction of the protein model and assignment of molecular mechanics parameters, but have then been developed to meet specialized objectives with respect to sampling and the energy function.

  17. Molecular modeling: An open invitation for applied mathematics

    NASA Astrophysics Data System (ADS)

    Mezey, Paul G.

    2013-10-01

    Molecular modeling methods provide a very wide range of challenges for innovative mathematical and computational techniques, where often high dimensionality, large sets of data, and complicated interrelations imply a multitude of iterative approximations. The physical and chemical basis of these methodologies involves quantum mechanics with several non-intuitive aspects, where classical interpretation and classical analogies are often misleading or outright wrong. Hence, instead of the everyday, common sense approaches which work so well in engineering, in molecular modeling one often needs to rely on rather abstract mathematical constraints and conditions, again emphasizing the high level of reliance on applied mathematics. Yet, the interdisciplinary aspects of the field of molecular modeling also generates some inertia and perhaps too conservative reliance on tried and tested methodologies, that is at least partially caused by the less than up-to-date involvement in the newest developments in applied mathematics. It is expected that as more applied mathematicians take up the challenge of employing the latest advances of their field in molecular modeling, important breakthroughs may follow. In this presentation some of the current challenges of molecular modeling are discussed.

  18. Advances in Applying Treatment Integrity Research for Dissemination and Implementation Science: Introduction to Special Issue

    PubMed Central

    Southam-Gerow, Michael A.; McLeod, Bryce D.

    2013-01-01

    This special series focuses upon the ways in which research on treatment integrity, a multidimensional construct including assessment of the content and quality of a psychosocial treatment delivered to a client as well as relational elements, can inform dissemination and implementation science. The five articles for this special series illustrate how treatment integrity concepts and methods can be applied across different levels of the mental health service system to advance dissemination and implementation science. In this introductory article, we provide an overview of treatment integrity research and describe three broad conceptual models that are relevant to the articles in the series. We conclude with a brief description of each of the five articles in the series. PMID:23970819

  19. Advanced panel-type influence coefficient methods applied to subsonic flows

    NASA Technical Reports Server (NTRS)

    Johnson, F. T.; Rubbert, P. E.

    1975-01-01

    An advanced technique for solving the linear integral equations of three-dimensional subsonic potential flows (steady, inviscid, irrotational and incompressible) about arbitrary configurations is presented. It involves assembling select, logically consistent networks whose construction comprises four tasks, which are described in detail: surface geometry definition; singularity strength definition; control point and boundary condition specification; and calculation of induced potential or velocity. The technique is applied to seven wing examples approached by four network types: source/analysis, doublet/analysis, source/design, and doublet/design. The results demonstrate the forgiveness of the model to irregular paneling and the practicality of combined analysis/design boundary conditions. The appearance of doublet strength mismatch is a valuable indicator of locally inadequate paneling.

  20. Linear mixing model applied to AVHRR LAC data

    NASA Technical Reports Server (NTRS)

    Holben, Brent N.; Shimabukuro, Yosio E.

    1993-01-01

    A linear mixing model was applied to coarse spatial resolution data from the NOAA Advanced Very High Resolution Radiometer. The reflective component of the 3.55 - 3.93 microns channel was extracted and used with the two reflective channels 0.58 - 0.68 microns and 0.725 - 1.1 microns to run a Constraine Least Squares model to generate vegetation, soil, and shade fraction images for an area in the Western region of Brazil. The Landsat Thematic Mapper data covering the Emas National park region was used for estimating the spectral response of the mixture components and for evaluating the mixing model results. The fraction images were compared with an unsupervised classification derived from Landsat TM data acquired on the same day. The relationship between the fraction images and normalized difference vegetation index images show the potential of the unmixing techniques when using coarse resolution data for global studies.

  1. Advanced modeling of high intensity accelerators

    SciTech Connect

    Ryne, R.D.; Habib, S.; Wangler, T.P.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goals of this project were three-fold: (1) to develop a new capability, based on high performance (parallel) computers, to perform large scale simulations of high intensity accelerators; (2) to apply this capability to modeling high intensity accelerators under design at LANL; and (3) to use this new capability to improve the understanding of the physics of intense charge particle beams, especially in regard to the issue of beam halo formation. All of these goals were met. In particular, the authors introduced split-operator methods as a powerful and efficient means to simulate intense beams in the presence of rapidly varying accelerating and focusing fields. They then applied these methods to develop scaleable, parallel beam dynamics codes for modeling intense beams in linacs, and in the process they implemented a new three-dimensional space charge algorithm. They also used the codes to study a number of beam dynamics issues related to the Accelerator Production of Tritium (APT) project, and in the process performed the largest simulations to date for any accelerator design project. Finally, they used the new modeling capability to provide direction and validation to beam physics studies, helping to identify beam mismatch as a major source of halo formation in high intensity accelerators. This LDRD project ultimately benefited not only LANL but also the US accelerator community since, by promoting expertise in high performance computing and advancing the state-of-the-art in accelerator simulation, its accomplishments helped lead to approval of a new DOE Grand Challenge in Computational Accelerator Physics.

  2. An Ecological and Conservation Perspective on Advances in the Applied Virology of Zoonoses

    PubMed Central

    Vandegrift, Kurt J.; Wale, Nina; Epstein, Jonathan H.

    2011-01-01

    The aim of this manuscript is to describe how modern advances in our knowledge of viruses and viral evolution can be applied to the fields of disease ecology and conservation. We review recent progress in virology and provide examples of how it is informing both empirical research in field ecology and applied conservation. We include a discussion of needed breakthroughs and ways to bridge communication gaps between the field and the lab. In an effort to foster this interdisciplinary effort, we have also included a table that lists the definitions of key terms. The importance of understanding the dynamics of zoonotic pathogens in their reservoir hosts is emphasized as a tool to both assess risk factors for spillover and to test hypotheses related to treatment and/or intervention strategies. In conclusion, we highlight the need for smart surveillance, viral discovery efforts and predictive modeling. A shift towards a predictive approach is necessary in today’s globalized society because, as the 2009 H1N1 pandemic demonstrated, identification post-emergence is often too late to prevent global spread. Integrating molecular virology and ecological techniques will allow for earlier recognition of potentially dangerous pathogens, ideally before they jump from wildlife reservoirs into human or livestock populations and cause serious public health or conservation issues. PMID:21994738

  3. An ecological and conservation perspective on advances in the applied virology of zoonoses.

    PubMed

    Vandegrift, Kurt J; Wale, Nina; Epstein, Jonathan H

    2011-04-01

    The aim of this manuscript is to describe how modern advances in our knowledge of viruses and viral evolution can be applied to the fields of disease ecology and conservation. We review recent progress in virology and provide examples of how it is informing both empirical research in field ecology and applied conservation. We include a discussion of needed breakthroughs and ways to bridge communication gaps between the field and the lab. In an effort to foster this interdisciplinary effort, we have also included a table that lists the definitions of key terms. The importance of understanding the dynamics of zoonotic pathogens in their reservoir hosts is emphasized as a tool to both assess risk factors for spillover and to test hypotheses related to treatment and/or intervention strategies. In conclusion, we highlight the need for smart surveillance, viral discovery efforts and predictive modeling. A shift towards a predictive approach is necessary in today's globalized society because, as the 2009 H1N1 pandemic demonstrated, identification post-emergence is often too late to prevent global spread. Integrating molecular virology and ecological techniques will allow for earlier recognition of potentially dangerous pathogens, ideally before they jump from wildlife reservoirs into human or livestock populations and cause serious public health or conservation issues.

  4. 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.

  5. Advances in Swine Biomedical Model Genomics

    PubMed Central

    Lunney, Joan K.

    2007-01-01

    This review is a short update on the diversity of swine biomedical models and the importance of genomics in their continued development. The swine has been used as a major mammalian model for human studies because of the similarity in size and physiology, and in organ development and disease progression. The pig model allows for deliberately timed studies, imaging of internal vessels and organs using standard human technologies, and collection of repeated peripheral samples and, at kill, detailed mucosal tissues. The ability to use pigs from the same litter, or cloned or transgenic pigs, facilitates comparative analyses and genetic mapping. The availability of numerous well defined cell lines, representing a broad range of tissues, further facilitates testing of gene expression, drug susceptibility, etc. Thus the pig is an excellent biomedical model for humans. For genomic applications it is an asset that the pig genome has high sequence and chromosome structure homology with humans. With the swine genome sequence now well advanced there are improving genetic and proteomic tools for these comparative analyses. The review will discuss some of the genomic approaches used to probe these models. The review will highlight genomic studies of melanoma and of infectious disease resistance, discussing issues to consider in designing such studies. It will end with a short discussion of the potential for genomic approaches to develop new alternatives for control of the most economically important disease of pigs, porcine reproductive and respiratory syndrome (PRRS), and the potential for applying knowledge gained with this virus for human viral infectious disease studies. PMID:17384736

  6. Coastal Modeling System Advanced Topics

    DTIC Science & Technology

    2012-06-18

    is the CMS? Integrated wave, current, and morphology change model in the Surface-water Modeling System (SMS). Why CMS? Operational at 10...Coupled with spectral wave model (CMS-Wave)  Wave-current interactions  Inline sediment transport and morphology change  Non-equilibrium...Easy to setup  Telescoping grid: Efficient and flexible  Solver options  Implicit: Tidal flow, long-term morphology change. ~10 min

  7. Applying model-based diagnostics to space power distribution

    NASA Astrophysics Data System (ADS)

    Quinn, Todd M.; Schlegelmilch, Richard F.

    1994-03-01

    When engineers diagnose system failures, they often use models to confirm system operation. This concept has produced a class of advanced expert systems which perform model-based diagnosis. A model-based diagnostic expert system for a Space Station Freedom electrical power distribution testbed is currently being developed at the NASA Lewis Research Center. The objective of this expert system is to autonomously detect and isolate electrical fault conditions. Marple, a software package developed at TRW, provides a model-based environment utilizing constraint suspension. Originally, constraint suspension techniques were developed for digital systems. However, Marple provides the mechanisms for applying this approach to analog systems, such as the testbed, as well. The expert system was developed using Marple and Lucid Common Lisp running on Sun Sparc-2 workstation. The Marple modeling environment has proved to be a useful tool for investigating the various aspects of model-based diagnostics. This paper describes work completed to date and lessons learned while employing model-based diagnostics using constraint suspension within an analog system.

  8. 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.

  9. Mathematical biodynamic feedthrough model applied to rotorcraft.

    PubMed

    Venrooij, Joost; Mulder, Mark; Abbink, David A; van Paassen, Marinus M; Mulder, Max; van der Helm, Frans C T; Bulthoff, Heinrich H

    2014-07-01

    Biodynamic feedthrough (BDFT) occurs when vehicle accelerations feed through the human body and cause involuntary control inputs. This paper proposes a model to quantitatively predict this effect in rotorcraft. This mathematical BDFT model aims to fill the gap between the currently existing black box BDFT models and physical BDFT models. The model structure was systematically constructed using asymptote modeling, a procedure described in detail in this paper. The resulting model can easily be implemented in many typical rotorcraft BDFT studies, using the provided model parameters. The model's performance was validated in both the frequency and time domain. Furthermore, it was compared with several recent BDFT models. The results show that the proposed mathematical model performs better than typical black box models and is easier to parameterize and implement than a recent physical model.

  10. Information theoretic model selection applied to supernovae data

    NASA Astrophysics Data System (ADS)

    Biesiada, Marek

    2007-02-01

    Current advances in observational cosmology suggest that our Universe is flat and dominated by dark energy. There are several different theoretical ideas invoked to explain the dark energy with relatively little guidance of which one of them might be right. Therefore the emphasis of ongoing and forthcoming research in this field shifts from estimating specific parameters of the cosmological model to the model selection. In this paper we apply an information theoretic model selection approach based on the Akaike criterion as an estimator of Kullback Leibler entropy. Although this approach has already been used by some authors in a similar context, this paper provides a more systematic introduction to the Akaike criterion. In particular, we present the proper way of ranking the competing models on the basis of Akaike weights (in Bayesian language: posterior probabilities of the models). This important ingredient is lacking from alternative studies dealing with cosmological applications of the Akaike criterion. Of the many particular models of dark energy we focus on four: quintessence, quintessence with a time varying equation of state, the braneworld scenario and the generalized Chaplygin gas model, and test them on Riess's gold sample. As a result we obtain that the best model—in terms of the Akaike criterion—is the quintessence model. The odds suggest that although there exist differences in the support given to specific scenarios by supernova data, most of the models considered receive similar support. The only exception is the Chaplygin gas which is considerably less supported. One can also note that models similar in structure, e.g. ΛCDM, quintessence and quintessence with a variable equation of state, are closer to each other in terms of Kullback Leibler entropy. Models having different structure, e.g. Chaplygin gas and the braneworld scenario, are more distant (in the Kullback Leibler sense) from the best one.

  11. Model Standards Advance the Profession

    ERIC Educational Resources Information Center

    Journal of Staff Development, 2011

    2011-01-01

    Leadership by teachers is essential to serving the needs of students, schools, and the teaching profession. To that end, the Teacher Leadership Exploratory Consortium has developed Teacher Leader Model Standards to codify, promote, and support teacher leadership as a vehicle to transform schools for the needs of the 21st century. The Teacher…

  12. Model Standards Advance the Profession

    ERIC Educational Resources Information Center

    Journal of Staff Development, 2011

    2011-01-01

    Leadership by teachers is essential to serving the needs of students, schools, and the teaching profession. To that end, the Teacher Leadership Exploratory Consortium has developed Teacher Leader Model Standards to codify, promote, and support teacher leadership as a vehicle to transform schools for the needs of the 21st century. The Teacher…

  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. 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.

  15. 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.

  16. Applying mechanistic models in bioprocess development.

    PubMed

    Lencastre Fernandes, Rita; Bodla, Vijaya Krishna; Carlquist, Magnus; Heins, Anna-Lena; Eliasson Lantz, Anna; Sin, Gürkan; Gernaey, Krist V

    2013-01-01

    The available knowledge on the mechanisms of a bioprocess system is central to process analytical technology. In this respect, mechanistic modeling has gained renewed attention, since a mechanistic model can provide an excellent summary of available process knowledge. Such a model therefore incorporates process-relevant input (critical process variables)-output (product concentration and product quality attributes) relations. The model therefore has great value in planning experiments, or in determining which critical process variables need to be monitored and controlled tightly. Mechanistic models should be combined with proper model analysis tools, such as uncertainty and sensitivity analysis. When assuming distributed inputs, the resulting uncertainty in the model outputs can be decomposed using sensitivity analysis to determine which input parameters are responsible for the major part of the output uncertainty. Such information can be used as guidance for experimental work; i.e., only parameters with a significant influence on model outputs need to be determined experimentally. The use of mechanistic models and model analysis tools is demonstrated in this chapter. As a practical case study, experimental data from Saccharomyces cerevisiae fermentations are used. The data are described with the well-known model of Sonnleitner and Käppeli (Biotechnol Bioeng 28:927-937, 1986) and the model is analyzed further. The methods used are generic, and can be transferred easily to other, more complex case studies as well.

  17. Applying Modeling Tools to Ground System Procedures

    NASA Technical Reports Server (NTRS)

    Di Pasquale, Peter

    2012-01-01

    As part of a long-term effort to revitalize the Ground Systems (GS) Engineering Section practices, Systems Modeling Language (SysML) and Business Process Model and Notation (BPMN) have been used to model existing GS products and the procedures GS engineers use to produce them.

  18. Applying Modeling Tools to Ground System Procedures

    NASA Technical Reports Server (NTRS)

    Di Pasquale, Peter

    2012-01-01

    As part of a long-term effort to revitalize the Ground Systems (GS) Engineering Section practices, Systems Modeling Language (SysML) and Business Process Model and Notation (BPMN) have been used to model existing GS products and the procedures GS engineers use to produce them.

  19. Analysis of Petroleum Technology Advances Through Applied Research by Independent Oil Producers

    SciTech Connect

    Brashear, Jerry P.; North, Walter B.; Thomas Charles P.; Becker, Alan B.; Faulder, David D.

    2000-01-12

    Petroleum Technology Advances Through Applied Research by Independent Oil Producers is a program of the National Oil Research Program, U.S. Department of Energy. Between 1995 and 1998, the program competitively selected and cost-shared twenty-two projects with small producers. The purpose was to involve small independent producers in testing technologies of interest to them that would advance (directly or indirectly) one or more of four national program objectives: (1) Extend the productive life of reservoirs; (2) Increase production and/or reserves; (3) Improve environmental performance; and (4) Broaden the exchange of technology information.

  20. Advances in Single-Particle Electron Cryomicroscopy Structure Determination applied to Sub-tomogram Averaging

    PubMed Central

    Bharat, Tanmay A.M.; Russo, Christopher J.; Löwe, Jan; Passmore, Lori A.; Scheres, Sjors H.W.

    2015-01-01

    Summary Recent innovations in specimen preparation, data collection, and image processing have led to improved structure determination using single-particle electron cryomicroscopy (cryo-EM). Here we explore some of these advances to improve structures determined using electron cryotomography (cryo-ET) and sub-tomogram averaging. We implement a new three-dimensional model for the contrast transfer function, and use this in a regularized likelihood optimization algorithm as implemented in the RELION program. Using direct electron detector data, we apply both single-particle analysis and sub-tomogram averaging to analyze radiation-induced movements of the specimen. As in single-particle cryo-EM, we find that significant sample movements occur during tomographic data acquisition, and that these movements are substantially reduced through the use of ultrastable gold substrates. We obtain a sub-nanometer resolution structure of the hepatitis B capsid, and show that reducing radiation-induced specimen movement may be central to attempts at further improving tomogram quality and resolution. PMID:26256537

  1. Building an advanced climate model: Program plan for the CHAMMP (Computer Hardware, Advanced Mathematics, and Model Physics) Climate Modeling Program

    SciTech Connect

    Not Available

    1990-12-01

    The issue of global warming and related climatic changes from increasing concentrations of greenhouse gases in the atmosphere has received prominent attention during the past few years. The Computer Hardware, Advanced Mathematics, and Model Physics (CHAMMP) Climate Modeling Program is designed to contribute directly to this rapid improvement. The goal of the CHAMMP Climate Modeling Program is to develop, verify, and apply a new generation of climate models within a coordinated framework that incorporates the best available scientific and numerical approaches to represent physical, biogeochemical, and ecological processes, that fully utilizes the hardware and software capabilities of new computer architectures, that probes the limits of climate predictability, and finally that can be used to address the challenging problem of understanding the greenhouse climate issue through the ability of the models to simulate time-dependent climatic changes over extended times and with regional resolution.

  2. Biplot models applied to cancer mortality rates.

    PubMed

    Osmond, C

    1985-01-01

    "A graphical method developed by Gabriel to display the rows and columns of a matrix is applied to tables of age- and period-specific cancer mortality rates. It is particularly useful when the pattern of age-specific rates changes with time. Trends in age-specific rates and changes in the age distribution are identified as projections. Three examples [from England and Wales] are given."

  3. A soil-plant model applied to phytoremediation of metals.

    PubMed

    Lugli, Francesco; Mahler, Claudio Fernando

    2016-01-01

    This study reports a phytoremediation pot experiment using an open-source program. Unsaturated water flow was described by the Richards' equation and solute transport by the advection-dispersion equation. Sink terms in the governing flow and transport equations accounted for root water and solute uptake, respectively. Experimental data were related to application of Vetiver grass to soil contaminated by metal ions. Sensitivity analysis revealed that due to the specific experimental set-up (bottom flux not allowed), hydraulic model parameters did not influence root water (and contaminant) uptake. In contrast, the results were highly correlated with plant solar radiation interception efficiency (leaf area index). The amounts of metals accumulated in the plant tissue were compared to numerical values of cumulative uptake. Pb(2+) and Zn(2+) uptake was satisfactorily described using a passive model. However, for Ni(2+) and Cd(2+), a specific calibration of the active uptake model was necessary. Calibrated MM parameters for Ni(2+), Cd(2+), and Pb(2+) were compared to values in the literature, generally suggesting lower rates and saturation advance. A parameter (saturation ratio) was introduced to assess the efficiency of contaminant uptake. Numerical analysis, applying actual field conditions, showed the limitation of the active model for being independent of the transpiration rate.

  4. Applying the take-grant protection model

    NASA Technical Reports Server (NTRS)

    Bishop, Matt

    1990-01-01

    The Take-Grant Protection Model has in the past been used to model multilevel security hierarchies and simple protection systems. The models are extended to include theft of rights and sharing information, and additional security policies are examined. The analysis suggests that in some cases the basic rules of the Take-Grant Protection Model should be augmented to represent the policy properly; when appropriate, such modifications are made and their efforts with respect to the policy and its Take-Grant representation are discussed.

  5. Applying the Sport Education Model to Tennis

    ERIC Educational Resources Information Center

    Ayvazo, Shiri

    2009-01-01

    The physical education field abounds with theoretically sound curricular approaches such as fitness education, skill theme approach, tactical approach, and sport education. In an era that emphasizes authentic sport experiences, the Sport Education Model includes unique features that sets it apart from other curricular models and can be a valuable…

  6. Applying the Sport Education Model to Tennis

    ERIC Educational Resources Information Center

    Ayvazo, Shiri

    2009-01-01

    The physical education field abounds with theoretically sound curricular approaches such as fitness education, skill theme approach, tactical approach, and sport education. In an era that emphasizes authentic sport experiences, the Sport Education Model includes unique features that sets it apart from other curricular models and can be a valuable…

  7. Recent advances in modeling stellar interiors

    NASA Astrophysics Data System (ADS)

    Guzik, Joyce Ann

    2011-11-01

    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 γ Dor/ δ Sct star pulsations, the cause of giant eruptions seen in luminous blue variables such as η Car and P Cyg, and the solar abundance problem.

  8. 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.

  9. Divorce and Child Behavior Problems: Applying Latent Change Score Models to Life Event Data

    ERIC Educational Resources Information Center

    Malone, Patrick S.; Lansford, Jennifer E.; Castellino, Domini R.; Berlin, Lisa J.; Dodge, Kenneth A.; Bates, John E.; Pettit, Gregory S.

    2004-01-01

    Effects of parents' divorce on children's adjustment have been studied extensively. This article applies new advances in trajectory modeling to the problem of disentangling the effects of divorce on children's adjustment from related factors such as the child's age at the time of divorce and the child's gender. Latent change score models were used…

  10. Divorce and Child Behavior Problems: Applying Latent Change Score Models to Life Event Data

    ERIC Educational Resources Information Center

    Malone, Patrick S.; Lansford, Jennifer E.; Castellino, Domini R.; Berlin, Lisa J.; Dodge, Kenneth A.; Bates, John E.; Pettit, Gregory S.

    2004-01-01

    Effects of parents' divorce on children's adjustment have been studied extensively. This article applies new advances in trajectory modeling to the problem of disentangling the effects of divorce on children's adjustment from related factors such as the child's age at the time of divorce and the child's gender. Latent change score models were used…

  11. Advanced Non-Linear Control Algorithms Applied to Design Highly Maneuverable Autonomous Underwater Vehicles (AUVs)

    DTIC Science & Technology

    2007-08-01

    Advanced non- linear control algorithms applied to design highly maneuverable Autonomous Underwater Vehicles (AUVs) Vladimir Djapic, Jay A. Farrell...hierarchical such that an ”inner loop” non- linear controller (outputs the appropriate thrust values) is the same for all mission scenarios while a...library of ”outer-loop” non- linear controllers are available to implement specific maneuvering scenarios. On top of the outer-loop is the mission planner

  12. Advances in Scientific Balloon Thermal Modeling

    NASA Technical Reports Server (NTRS)

    Bohaboj, T.; Cathey, H. M., Jr.

    2004-01-01

    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 "Thrmal 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 papa 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.

  13. Advances in Scientific Balloon Thermal Modeling

    NASA Technical Reports Server (NTRS)

    Bohaboj, T.; Cathey, H. M., Jr.

    2004-01-01

    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 "Thrmal 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 papa 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.

  14. 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.

  15. Relative Binding Free Energy Calculations Applied to Protein Homology Models.

    PubMed

    Cappel, Daniel; Hall, Michelle Lynn; Lenselink, Eelke B; Beuming, Thijs; Qi, Jun; Bradner, James; Sherman, Woody

    2016-12-27

    A significant challenge and potential high-value application of computer-aided drug design is the accurate prediction of protein-ligand binding affinities. Free energy perturbation (FEP) using molecular dynamics (MD) sampling is among the most suitable approaches to achieve accurate binding free energy predictions, due to the rigorous statistical framework of the methodology, correct representation of the energetics, and thorough treatment of the important degrees of freedom in the system (including explicit waters). Recent advances in sampling methods and force fields coupled with vast increases in computational resources have made FEP a viable technology to drive hit-to-lead and lead optimization, allowing for more efficient cycles of medicinal chemistry and the possibility to explore much larger chemical spaces. However, previous FEP applications have focused on systems with high-resolution crystal structures of the target as starting points-something that is not always available in drug discovery projects. As such, the ability to apply FEP on homology models would greatly expand the domain of applicability of FEP in drug discovery. In this work we apply a particular implementation of FEP, called FEP+, on congeneric ligand series binding to four diverse targets: a kinase (Tyk2), an epigenetic bromodomain (BRD4), a transmembrane GPCR (A2A), and a protein-protein interaction interface (BCL-2 family protein MCL-1). We apply FEP+ using both crystal structures and homology models as starting points and find that the performance using homology models is generally on a par with the results when using crystal structures. The robustness of the calculations to structural variations in the input models can likely be attributed to the conformational sampling in the molecular dynamics simulations, which allows the modeled receptor to adapt to the "real" conformation for each ligand in the series. This work exemplifies the advantages of using all-atom simulation methods with

  16. 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.

  17. 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.

  18. Applying Machine Trust Models to Forensic Investigations

    NASA Astrophysics Data System (ADS)

    Wojcik, Marika; Venter, Hein; Eloff, Jan; Olivier, Martin

    Digital forensics involves the identification, preservation, analysis and presentation of electronic evidence for use in legal proceedings. In the presence of contradictory evidence, forensic investigators need a means to determine which evidence can be trusted. This is particularly true in a trust model environment where computerised agents may make trust-based decisions that influence interactions within the system. This paper focuses on the analysis of evidence in trust-based environments and the determination of the degree to which evidence can be trusted. The trust model proposed in this work may be implemented in a tool for conducting trust-based forensic investigations. The model takes into account the trust environment and parameters that influence interactions in a computer network being investigated. Also, it allows for crimes to be reenacted to create more substantial evidentiary proof.

  19. Polarization model applied to Uranian radio emission

    NASA Astrophysics Data System (ADS)

    Sawyer, C. B.; Neal, K. L.; Warwick, J. W.

    1991-04-01

    The total power and the degree of circular polarization as measured by the Planetary Radio Astronomy experiments on the Voyager spacecraft are modeled. For a source near the electron cyclotron frequency, the degree of circular polarization is determined by the angle between the wave vector and the field. It is shown that the observed strong circular polarization of Uranian smooth low-frequency (SLF) can be modeled as emission that is beamed along the direction of the magnetic field in a filled cone. The main observational constraints of SLF emission from Uranus are met by conjugate sources at about 21 deg from the magnetic equator.

  20. 25 CFR 1000.53 - Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 2 2012-04-01 2012-04-01 false Can Tribes/Consortia that receive advance planning grants... Advance Planning Grant Funding § 1000.53 Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant? Yes, Tribes/Consortia that successfully complete the planning...

  1. 25 CFR 1000.53 - Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 2 2011-04-01 2011-04-01 false Can Tribes/Consortia that receive advance planning grants... Advance Planning Grant Funding § 1000.53 Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant? Yes, Tribes/Consortia that successfully complete the planning...

  2. 25 CFR 1000.53 - Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 2 2013-04-01 2013-04-01 false Can Tribes/Consortia that receive advance planning grants... Advance Planning Grant Funding § 1000.53 Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant? Yes, Tribes/Consortia that successfully complete the planning...

  3. 25 CFR 1000.53 - Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 2 2014-04-01 2014-04-01 false Can Tribes/Consortia that receive advance planning grants... Advance Planning Grant Funding § 1000.53 Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant? Yes, Tribes/Consortia that successfully complete the planning...

  4. 25 CFR 1000.53 - Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Can Tribes/Consortia that receive advance planning grants... Advance Planning Grant Funding § 1000.53 Can Tribes/Consortia that receive advance planning grants also apply for a negotiation grant? Yes, Tribes/Consortia that successfully complete the planning...

  5. Thermal modelling of Advanced LIGO test masses

    NASA Astrophysics Data System (ADS)

    Wang, H.; Blair, C.; Dovale Álvarez, M.; Brooks, A.; Kasprzack, M. F.; Ramette, J.; Meyers, P. M.; Kaufer, S.; O'Reilly, B.; Mow-Lowry, C. M.; Freise, A.

    2017-06-01

    High-reflectivity fused silica mirrors are at the epicentre of today’s advanced gravitational wave detectors. In these detectors, the mirrors interact with high power laser beams. As a result of finite absorption in the high reflectivity coatings the mirrors suffer from a variety of thermal effects that impact on the detectors’ performance. We propose a model of the Advanced LIGO mirrors that introduces an empirical term to account for the radiative heat transfer between the mirror and its surroundings. The mechanical mode frequency is used as a probe for the overall temperature of the mirror. The thermal transient after power build-up in the optical cavities is used to refine and test the model. The model provides a coating absorption estimate of 1.5-2.0 ppm and estimates that 0.3 to 1.3 ppm of the circulating light is scattered onto the ring heater.

  6. Advanced Behavioral Applications in Schools: A Review of R. Douglas Greer's "Designing Teaching Strategies: An Applied Behavior Analysis Systems Approach"

    ERIC Educational Resources Information Center

    Moxley, Roy A.

    2004-01-01

    R. Douglas Greer's "Designing Teaching Strategies" is an important book directed to advanced students in applied behavior analysis for classrooms. This review presents some of the striking features of the Comprehensive Applied Behavior Analysis to Schooling (CABAS[R]) program and the individualized instruction that the book advances. These include…

  7. Advanced Behavioral Applications in Schools: A Review of R. Douglas Greer's "Designing Teaching Strategies: An Applied Behavior Analysis Systems Approach"

    ERIC Educational Resources Information Center

    Moxley, Roy A.

    2004-01-01

    R. Douglas Greer's "Designing Teaching Strategies" is an important book directed to advanced students in applied behavior analysis for classrooms. This review presents some of the striking features of the Comprehensive Applied Behavior Analysis to Schooling (CABAS[R]) program and the individualized instruction that the book advances. These include…

  8. 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.

  9. Private healthcare quality: applying a SERVQUAL model.

    PubMed

    Butt, Mohsin Muhammad; de Run, Ernest Cyril

    2010-01-01

    This paper seeks to develop and test the SERVQUAL model scale for measuring Malaysian private health service quality. The study consists of 340 randomly selected participants visiting a private healthcare facility during a three-month data collection period. Data were analyzed using means, correlations, principal component and confirmatory factor analysis to establish the modified SERVQUAL scale's reliability, underlying dimensionality and convergent, discriminant validity. Results indicate a moderate negative quality gap for overall Malaysian private healthcare service quality. Results also indicate a moderate negative quality gap on each service quality scale dimension. However, scale development analysis yielded excellent results, which can be used in wider healthcare policy and practice. Respondents were skewed towards a younger population, causing concern that the results might not represent all Malaysian age groups. The study's major contribution is that it offers a way to assess private healthcare service quality. Second, it successfully develops a scale that can be used to measure health service quality in Malaysian contexts.

  10. Subpixels analysis model applied to floodplain monitoring

    NASA Astrophysics Data System (ADS)

    Giraldo Osorio, J. D.; García Galiano, S. G.

    2009-04-01

    The traditional techniques to gauge hydrological events often fail with the extreme events. A particular case is the floods spatial detection. In this work, the remote sensing techniques and Geographic Information Systems (GIS) have been merged to develop a key tool for monitoring of floods. The low density of gauge stations networks in the development countries becomes remote sensing techniques the most suitable and economic way to delimitate the flood area and compute the damages cost. The common classification techniques of satellite images use "hard methods" in the sense of a pixel is assigned to an unique land cover class. For coarse resolution, the pixels inevitably will be mixed, so "soft methods" can be used in order to assign several land cover classes according to the surface fractions covered by each one. The main objective of this work is the dynamic monitoring of floods in large areas, based on satellite images -with moderate spatial resolution but with high time resolution- and Digital Elevation Model (DEM). Classified maps with finer spatial resolution can be built through the methodology of Subpixels Analysis developed. The procedure is supported on both the Linear Mixture Model (LMM) and Spatial Coherence Analysis (SCA) hypothesis. The LMM builds the land cover fraction maps through an optimization procedure which uses Lagrange Multipliers, while the SCA defines the most likely place for the land cover fractions within the coarse pixel using linear programming. A subsequent procedure improves the flooded area identification using both the drainage direction and flow accumulation raster maps derived from DEM of the study zone. The Subpixels Analysis technique was validated using historical data of floods which were obtained from satellite images. The procedure improves the spatial resolution of classified maps from satellite images with coarse resolution, while the "hard methods" keep the spatial resolution from the input coarse satellite image.

  11. Aeroheating model advancements featuring electroless metallic plating

    NASA Technical Reports Server (NTRS)

    Stalmach, C. J., Jr.; Goodrich, W. D.

    1976-01-01

    Discussed are advancements in wind tunnel model construction methods and hypersonic test data demonstrating the methods. The general objective was to develop model fabrication methods for improved heat transfer measuring capability at less model cost. A plated slab model approach was evaluated with cast models containing constantan wires that formed single-wire-to-plate surface thermocouple junctions with a seamless skin of electroless nickel alloy. The surface of a space shuttle orbiter model was selectively plated with scaled tiles to simulate, with high fidelity, the probable misalignments of the heatshield tiles on a flight vehicle. Initial, Mach 8 heating results indicated a minor effect of tile misalignment roughness on boundary layer transition, implying a possible relaxation of heatshield manufacturing tolerances. Some loss of the plated tiles was experienced when the model was tested at high heating rates.

  12. Aeroheating model advancements featuring electroless metallic plating

    NASA Technical Reports Server (NTRS)

    Stalmach, C. J., Jr.; Goodrich, W. D.

    1976-01-01

    Discussed are advancements in wind tunnel model construction methods and hypersonic test data demonstrating the methods. The general objective was to develop model fabrication methods for improved heat transfer measuring capability at less model cost. A plated slab model approach was evaluated with cast models containing constantan wires that formed single-wire-to-plate surface thermocouple junctions with a seamless skin of electroless nickel alloy. The surface of a space shuttle orbiter model was selectively plated with scaled tiles to simulate, with high fidelity, the probable misalignments of the heatshield tiles on a flight vehicle. Initial, Mach 8 heating results indicated a minor effect of tile misalignment roughness on boundary layer transition, implying a possible relaxation of heatshield manufacturing tolerances. Some loss of the plated tiles was experienced when the model was tested at high heating rates.

  13. Applied Research Consultants (ARC): A Vertical Practicum Model of Training Applied Research

    ERIC Educational Resources Information Center

    Nadler, Joel T.; Cundiff, Nicole L.

    2009-01-01

    The demand for highly trained evaluation consultants is increasing. Furthermore, the gap between job seekers' evaluation competencies and job recruiters' expectations suggests a need for providing practical training experiences. A model using a vertical practicum (advanced students assisting in the training of newer students) is suggested as an…

  14. 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).

  15. 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.

  16. Learning to Apply Models of Materials While Explaining Their Properties

    ERIC Educational Resources Information Center

    Karpin, Tiia; Juuti, Kalle; Lavonen, Jari

    2014-01-01

    Background: Applying structural models is important to chemistry education at the upper secondary level, but it is considered one of the most difficult topics to learn. Purpose: This study analyses to what extent in designed lessons students learned to apply structural models in explaining the properties and behaviours of various materials.…

  17. 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.

  18. 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.

  19. Enabling Technologies for Advanced Soft Tissue Modeling

    DTIC Science & Technology

    2005-09-01

    Matlab (Mathworks, Natick, MA) and ABAQUS environments in order to perform the optimization, minimizing the mean-square error between the experimental...been working on implementing the model in real-time using uniaxial compression breast data and a modified version of the model written to run in Matlab ...perfused whole organ testing 21 were noted and the load was applied in pseudo -random 77 order for 300 s, with repetition of the first load at the Following

  20. Advanced automation concepts applied to Experimental Breeder Reactor-II startup

    SciTech Connect

    Berkan, R.C.; Upadhyaya, B.R.; Bywater, R.L. . Dept. of Nuclear Engineering); Kisner, R.A. )

    1991-08-01

    The major objective of this work is to demonstrate through simulations that advanced liquid-metal reactor plants can be operated from low power by computer control. Development of an automatic control system with this objective will help resolve specific issues and provide proof through demonstration that automatic control for plant startup is feasible. This paper presents an advanced control system design for startup of the Experimental Breeder Reactor-2 (EBR-2) located at Idaho Falls, Idaho. The design incorporates recent methods in nonlinear control with advanced diagnostics techniques such as neural networks to form an integrated architecture. The preliminary evaluations are obtained in a simulated environment by a low-order, valid nonlinear model. Within the framework of phase 1 research, the design includes an inverse dynamics controller, a fuzzy controller, and an artificial neural network controller. These three nonlinear control modules are designed to follow the EBR-2 startup trajectories in a multi-input/output regime. They are coordinated by a supervisory routine to yield a fault-tolerant, parallel operation. The control system operates in three modes: manual, semiautomatic, and fully automatic control. The simulation results of the EBR-2 startup transients proved the effectiveness of the advanced concepts. The work presented in this paper is a preliminary feasibility analysis and does not constitute a final design of an automated startup control system for EBR-2. 14 refs., 43 figs.

  1. Advancements in predictive plasma formation modeling

    NASA Astrophysics Data System (ADS)

    Purvis, Michael A.; Schafgans, Alexander; Brown, Daniel J. W.; Fomenkov, Igor; Rafac, Rob; Brown, Josh; Tao, Yezheng; Rokitski, Slava; Abraham, Mathew; Vargas, Mike; Rich, Spencer; Taylor, Ted; Brandt, David; Pirati, Alberto; Fisher, Aaron; Scott, Howard; Koniges, Alice; Eder, David; Wilks, Scott; Link, Anthony; Langer, Steven

    2016-03-01

    We present highlights from plasma simulations performed in collaboration with Lawrence Livermore National Labs. This modeling is performed to advance the rate of learning about optimal EUV generation for laser produced plasmas and to provide insights where experimental results are not currently available. The goal is to identify key physical processes necessary for an accurate and predictive model capable of simulating a wide range of conditions. This modeling will help to drive source performance scaling in support of the EUV Lithography roadmap. The model simulates pre-pulse laser interaction with the tin droplet and follows the droplet expansion into the main pulse target zone. Next, the interaction of the expanded droplet with the main laser pulse is simulated. We demonstrate the predictive nature of the code and provide comparison with experimental results.

  2. 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

  3. Defining Requirements and Applying Information Modeling for Protecting Enterprise Assets

    NASA Astrophysics Data System (ADS)

    Fortier, Stephen C.; Volk, Jennifer H.

    The advent of terrorist threats has heightened local, regional, and national governments' interest in emergency response and disaster preparedness. The threat of natural disasters also challenges emergency responders to act swiftly and in a coordinated fashion. When a disaster occurs, an ad hoc coalition of pre-planned groups usually forms to respond to the incident. History has shown that these “system of systems” do not interoperate very well. Communications between fire, police and rescue components either do not work or are inefficient. Government agencies, non-governmental organizations (NGOs), and private industry use a wide array of software platforms for managing data about emergency conditions, resources and response activities. Most of these are stand-alone systems with very limited capability for data sharing with other agencies or other levels of government. Information technology advances have facilitated the movement towards an integrated and coordinated approach to emergency management. Other communication mechanisms, such as video teleconferencing, digital television and radio broadcasting, are being utilized to combat the challenges of emergency information exchange. Recent disasters, such as Hurricane Katrina and the tsunami in Indonesia, have illuminated the weaknesses in emergency response. This paper will discuss the need for defining requirements for components of ad hoc coalitions which are formed to respond to disasters. A goal of our effort was to develop a proof of concept that applying information modeling to the business processes used to protect and mitigate potential loss of an enterprise was feasible. These activities would be modeled both pre- and post-incident.

  4. Fate and efficacy of polyacrylamide applied in furrow irrigation: full-advance and continuous treatments.

    PubMed

    Lentz, Rodrick D; Sojka, Robert E; Mackey, Bruce E

    2002-01-01

    Polyacrylamide (PAM) is applied to 400000 irrigated hectares annually in the USA to control irrigation-induced erosion, yet the fate of dissolved PAM applied in irrigation water is not well documented. We determined the fate of PAM added to furrow streams under two treatments: Initial-10, 10 mg L(-1) PAM product applied only during the initial hours of the irrigation, and Cont-1, 1.0 mg L(-1) PAM product applied continuously during the entire irrigation. The study measured PAM concentrations in 167-m-long PAM-treated furrow streams and along a 530-m tail ditch that received this runoff. Soil was Portneuf silt loam (coarse-silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid) with 1.5% slope. Samples were taken at three times during the irrigations, both during and after PAM application. Polyacrylamide was adsorbed to soil and removed from solution as the streams traversed the soil-lined channels. The removal rate increased with stream sediment concentration. Stream sediment concentrations were higher when PAM concentrations were <2 mg L(-1) a.i., for early irrigations, and when untreated tributary flows combined with the stream. In these cases, PAM concentration decreased to undetectable levels over the flow lengths used in this study. When inflows contained >6 mg L(-1) PAM a.i., stream sediment concentrations were minimal and PAM concentrations did not change down the furrow, though they decreased to undetectable levels within 0.5 h after application ceased. One percent of applied PAM was lost in tail-ditch runoff. This loss could have been eliminated by treating only the furrow advance or not treating the last two irrigations.

  5. Advanced technologies applied to reduce the operating costs of small commuter transport aircraft

    NASA Technical Reports Server (NTRS)

    Masefield, O.; Turi, A.; Reinicke, M.

    1982-01-01

    The application of new aerodynamic, structural, and propulsion technologies to a specified baseline commuter aircraft is studied. The assessment models can be used on a desktop calculator and include a sizing program, operating cost program, and passenger ride qualities model. Evaluation is done with a step-by-step approach and is applied to range, number and type of engines, structure, wing selection, and configuration. A 40 percent direct operating cost saving is anticipated compared to current well established commuter aircraft.

  6. 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.

  7. Charmonium sum rules applied to a holographic model

    SciTech Connect

    Hohler, Paul M.

    2011-01-15

    The heavy-quark QCD sum rules are applied to a model of charmonium based upon the gauge/gravity duality. We find that there is strong agreement between the moments of the polarization function calculated from the holographic model and the experimental data suggesting that the model is consistent with the heavy-quark QCD sum rules at zero temperature.

  8. AFDM: An Advanced Fluid-Dynamics Model

    SciTech Connect

    Wilhelm, D.

    1990-09-01

    This volume describes the Advanced Fluid-Dynamics Model (AFDM) for topologies, flow regimes, and interfacial areas. The objective of these models is to provide values for the interfacial areas between all components existing in a computational cell. The interfacial areas are then used to evaluate the mass, energy, and momentum transfer between the components. A new approach has been undertaken in the development of a model to convect the interfacial areas of the discontinuous velocity fields in the three-velocity-field environment of AFDM. These interfacial areas are called convectible surface areas. The continuous and discontinuous components are chosen using volume fraction and levitation criteria. This establishes so-called topologies for which the convectible surface areas can be determined. These areas are functions of space and time. Solid particulates that are limited to being discontinuous within the bulk fluid are assumed to have a constant size. The convectible surface areas are subdivided to model contacts between two discontinuous components or discontinuous components and the structure. The models have been written for the flow inside of large pools. Therefore, the structure is tracked only as a boundary to the fluid volume without having a direct influence on velocity or volume fraction distribution by means of flow regimes or boundary layer models. 17 refs., 7 tabs., 18 figs.

  9. Applying modeling Results in designing a global tropospheric experiment

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A set of field experiments and advanced modeling studies which provide a strategy for a program of global tropospheric experiments was identified. An expanded effort to develop space applications for trospheric air quality monitoring and studies was recommended. The tropospheric ozone, carbon, nitrogen, and sulfur cycles are addressed. Stratospheric-tropospheric exchange is discussed. Fast photochemical processes in the free troposphere are considered.

  10. 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.

  11. Prospects for advanced RF theory and modeling

    NASA Astrophysics Data System (ADS)

    Batchelor, D. B.

    1999-09-01

    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.

  12. Micromechanical Modeling Efforts for Advanced Composites

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Over the past two decades, NASA Lewis Research Center's in-house efforts in analytical modeling for advanced composites have yielded several computational predictive tools. These are, in general, based on simplified micromechanics equations. During the last 3 years, our efforts have been directed primarily toward developing prediction tools for high temperature ceramic matrix composite (CMC's) materials. These materials are being considered for High Speed Research program applications, specifically for combustor liners. In comparison to conventional materials, CMC's offer several advantages: high specific stiffness and strength, and higher toughness and nonbrittle failure in comparison to monolithic ceramics, as well as environmental stability and wear resistance for both roomtemperature and elevated-temperature applications. Under the sponsorship of the High Temperature Engine Materials Program (HITEMP), CMC analytical modeling has resulted in the computational tool Ceramic Matrix Composites Analyzer (CEMCAN).

  13. Advanced laser modeling with BLAZE multiphysics

    NASA Astrophysics Data System (ADS)

    Palla, Andrew D.; Carroll, David L.; Gray, Michael I.; Suzuki, Lui

    2017-01-01

    The BLAZE Multiphysics™ software simulation suite was specifically developed to model highly complex multiphysical systems in a computationally efficient and highly scalable manner. These capabilities are of particular use when applied to the complexities associated with high energy laser systems that combine subsonic/transonic/supersonic fluid dynamics, chemically reacting flows, laser electronics, heat transfer, optical physics, and in some cases plasma discharges. In this paper we present detailed cw and pulsed gas laser calculations using the BLAZE model with comparisons to data. Simulations of DPAL, XPAL, ElectricOIL (EOIL), and the optically pumped rare gas laser were found to be in good agreement with experimental data.

  14. Dynamical real space renormalization group applied to sandpile models.

    PubMed

    Ivashkevich, E V; Povolotsky, A M; Vespignani, A; Zapperi, S

    1999-08-01

    A general framework for the renormalization group analysis of self-organized critical sandpile models is formulated. The usual real space renormalization scheme for lattice models when applied to nonequilibrium dynamical models must be supplemented by feedback relations coming from the stationarity conditions. On the basis of these ideas the dynamically driven renormalization group is applied to describe the boundary and bulk critical behavior of sandpile models. A detailed description of the branching nature of sandpile avalanches is given in terms of the generating functions of the underlying branching process.

  15. 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.

  16. 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

  17. Advances in a distributed approach for ocean model data interoperability

    USGS Publications Warehouse

    Signell, Richard P.; Snowden, Derrick P.

    2014-01-01

    An infrastructure for earth science data is emerging across the globe based on common data models and web services. As we evolve from custom file formats and web sites to standards-based web services and tools, data is becoming easier to distribute, find and retrieve, leaving more time for science. We describe recent advances that make it easier for ocean model providers to share their data, and for users to search, access, analyze and visualize ocean data using MATLAB® and Python®. These include a technique for modelers to create aggregated, Climate and Forecast (CF) metadata convention datasets from collections of non-standard Network Common Data Form (NetCDF) output files, the capability to remotely access data from CF-1.6-compliant NetCDF files using the Open Geospatial Consortium (OGC) Sensor Observation Service (SOS), a metadata standard for unstructured grid model output (UGRID), and tools that utilize both CF and UGRID standards to allow interoperable data search, browse and access. We use examples from the U.S. Integrated Ocean Observing System (IOOS®) Coastal and Ocean Modeling Testbed, a project in which modelers using both structured and unstructured grid model output needed to share their results, to compare their results with other models, and to compare models with observed data. The same techniques used here for ocean modeling output can be applied to atmospheric and climate model output, remote sensing data, digital terrain and bathymetric data.

  18. Advances in Modeling Exploding Bridgewire Initiation

    SciTech Connect

    Hrousis, C A; Christensen, J S

    2010-03-10

    There is great interest in applying magnetohydrodynamic (MHD) simulation techniques to the designs of electrical high explosive (HE) initiators, for the purpose of better understanding a design's sensitivities, optimizing its performance, and/or predicting its useful lifetime. Two MHD-capable LLNL codes, CALE and ALE3D, are being used to simulate the process of ohmic heating, vaporization, and plasma formation in exploding bridgewires (EBW). Initiation of the HE is simulated using Ignition & Growth reactive flow models. 1-D, 2-D and 3-D models have been constructed and studied. The models provide some intuitive explanation of the initiation process and are useful for evaluating the potential impact of identified aging mechanisms (such as the growth of intermetallic compounds or powder sintering). The end product of this work is a simulation capability for evaluating margin in proposed, modified or aged initiation system designs.

  19. An Application of the Programmatic Organization Model to Applied Research.

    ERIC Educational Resources Information Center

    Haring, Norris G.; Krug, David A.

    Presented is a programatic organization model which is applied to research needs in special education. Major advantages of the model are given to be that of providing for several research activities which focus on one common problem, reducing the duplication of research effort, providing greater efficiency in use of research personnel and…

  20. Modeling Protein Folding and Applying It to a Relevant Activity

    ERIC Educational Resources Information Center

    Nelson, Allan; Goetze, Jim

    2004-01-01

    The different levels of protein structure that can be easily understood by creating a model that simulates protein folding, which can then be evaluated by applying it to a relevant activity, is presented. The materials required and the procedure for constructing a protein folding model are mentioned.

  1. Applying the ARCS Motivation Model in Technological and Vocational Education

    ERIC Educational Resources Information Center

    Liao, Hung-Chang; Wang, Ya-huei

    2008-01-01

    This paper describes the incorporation of Keller's ARCS (Attention, Relevance, Confidence, and Satisfaction) motivation model into traditional classroom instruction-learning process. Viewing that technological and vocational students have low confidence and motivation in learning, the authors applied the ARCS motivation model not only in the…

  2. The HPT Model Applied to a Kayak Company's Registration Process

    ERIC Educational Resources Information Center

    Martin, Florence; Hall, Herman A., IV; Blakely, Amanda; Gayford, Matthew C.; Gunter, Erin

    2009-01-01

    This case study describes the step-by-step application of the traditional human performance technology (HPT) model at a premier kayak company located on the coast of North Carolina. The HPT model was applied to address lost revenues related to three specific business issues: misinformed customers, dissatisfied customers, and guides not showing up…

  3. Modeling theory applied: Modeling Instruction in introductory physics

    NASA Astrophysics Data System (ADS)

    Brewe, Eric

    2008-12-01

    Modeling Instruction is a pedagogical approach which has been widely and successfully employed in high school physics instruction but is not commonly used at the university level. The goal of this paper is to describe the nature of Modeling Instruction at the university level and to clarify the role of models in physics instruction. A university physics class is described as it progresses through a typical modeling cycle, Introduction and Representation, Coordination of Representations, Abstraction and Generalization, and Application and Refinement. The benefits of modeling instruction are discussed.

  4. LEARNING SEMANTICS-ENHANCED LANGUAGE MODELS APPLIED TO UNSUEPRVISED WSD

    SciTech Connect

    VERSPOOR, KARIN; LIN, SHOU-DE

    2007-01-29

    An N-gram language model aims at capturing statistical syntactic word order information from corpora. Although the concept of language models has been applied extensively to handle a variety of NLP problems with reasonable success, the standard model does not incorporate semantic information, and consequently limits its applicability to semantic problems such as word sense disambiguation. We propose a framework that integrates semantic information into the language model schema, allowing a system to exploit both syntactic and semantic information to address NLP problems. Furthermore, acknowledging the limited availability of semantically annotated data, we discuss how the proposed model can be learned without annotated training examples. Finally, we report on a case study showing how the semantics-enhanced language model can be applied to unsupervised word sense disambiguation with promising results.

  5. An advanced shape-fitting algorithm applied to quadrupedal mammals: improving volumetric mass estimates.

    PubMed

    Brassey, Charlotte A; Gardiner, James D

    2015-08-01

    Body mass is a fundamental physical property of an individual and has enormous bearing upon ecology and physiology. Generating reliable estimates for body mass is therefore a necessary step in many palaeontological studies. Whilst early reconstructions of mass in extinct species relied upon isolated skeletal elements, volumetric techniques are increasingly applied to fossils when skeletal completeness allows. We apply a new 'alpha shapes' (α-shapes) algorithm to volumetric mass estimation in quadrupedal mammals. α-shapes are defined by: (i) the underlying skeletal structure to which they are fitted; and (ii) the value α, determining the refinement of fit. For a given skeleton, a range of α-shapes may be fitted around the individual, spanning from very coarse to very fine. We fit α-shapes to three-dimensional models of extant mammals and calculate volumes, which are regressed against mass to generate predictive equations. Our optimal model is characterized by a high correlation coefficient and mean square error (r (2)=0.975, m.s.e.=0.025). When applied to the woolly mammoth (Mammuthus primigenius) and giant ground sloth (Megatherium americanum), we reconstruct masses of 3635 and 3706 kg, respectively. We consider α-shapes an improvement upon previous techniques as resulting volumes are less sensitive to uncertainties in skeletal reconstructions, and do not require manual separation of body segments from skeletons.

  6. An advanced shape-fitting algorithm applied to quadrupedal mammals: improving volumetric mass estimates

    PubMed Central

    Brassey, Charlotte A.; Gardiner, James D.

    2015-01-01

    Body mass is a fundamental physical property of an individual and has enormous bearing upon ecology and physiology. Generating reliable estimates for body mass is therefore a necessary step in many palaeontological studies. Whilst early reconstructions of mass in extinct species relied upon isolated skeletal elements, volumetric techniques are increasingly applied to fossils when skeletal completeness allows. We apply a new ‘alpha shapes’ (α-shapes) algorithm to volumetric mass estimation in quadrupedal mammals. α-shapes are defined by: (i) the underlying skeletal structure to which they are fitted; and (ii) the value α, determining the refinement of fit. For a given skeleton, a range of α-shapes may be fitted around the individual, spanning from very coarse to very fine. We fit α-shapes to three-dimensional models of extant mammals and calculate volumes, which are regressed against mass to generate predictive equations. Our optimal model is characterized by a high correlation coefficient and mean square error (r2=0.975, m.s.e.=0.025). When applied to the woolly mammoth (Mammuthus primigenius) and giant ground sloth (Megatherium americanum), we reconstruct masses of 3635 and 3706 kg, respectively. We consider α-shapes an improvement upon previous techniques as resulting volumes are less sensitive to uncertainties in skeletal reconstructions, and do not require manual separation of body segments from skeletons. PMID:26361559

  7. Initial Assessment of Open Rotor Propulsion Applied to an Advanced Single-Aisle Aircraft

    NASA Technical Reports Server (NTRS)

    Guynn, Mark D.; Berton, Jeffrey J.; Hendricks, Eric S.; Tong, Michael T.; Haller, William J.; Thurman, Douglas R.

    2011-01-01

    Application of high speed, advanced turboprops, or propfans, to subsonic transport aircraft received significant attention and research in the 1970s and 1980s when fuel efficiency was the driving focus of aeronautical research. Recent volatility in fuel prices and concern for aviation s environmental impact have renewed interest in unducted, open rotor propulsion, and revived research by NASA and a number of engine manufacturers. Unfortunately, in the two decades that have passed since open rotor concepts were thoroughly investigated, NASA has lost experience and expertise in this technology area. This paper describes initial efforts to re-establish NASA s capability to assess aircraft designs with open rotor propulsion. Specifically, methodologies for aircraft-level sizing, performance analysis, and system-level noise analysis are described. Propulsion modeling techniques have been described in a previous paper. Initial results from application of these methods to an advanced single-aisle aircraft using open rotor engines based on historical blade designs are presented. These results indicate open rotor engines have the potential to provide large reductions in fuel consumption and emissions. Initial noise analysis indicates that current noise regulations can be met with old blade designs and modern, noiseoptimized blade designs are expected to result in even lower noise levels. Although an initial capability has been established and initial results obtained, additional development work is necessary to make NASA s open rotor system analysis capability on par with existing turbofan analysis capabilities.

  8. Advanced Numerical Model for Irradiated Concrete

    SciTech Connect

    Giorla, Alain B.

    2015-03-01

    In this report, we establish a numerical model for concrete exposed to irradiation to address these three critical points. The model accounts for creep in the cement paste and its coupling with damage, temperature and relative humidity. The shift in failure mode with the loading rate is also properly represented. The numerical model for creep has been validated and calibrated against different experiments in the literature [Wittmann, 1970, Le Roy, 1995]. Results from a simplified model are shown to showcase the ability of numerical homogenization to simulate irradiation effects in concrete. In future works, the complete model will be applied to the analysis of the irradiation experiments of Elleuch et al. [1972] and Kelly et al. [1969]. This requires a careful examination of the experimental environmental conditions as in both cases certain critical information are missing, including the relative humidity history. A sensitivity analysis will be conducted to provide lower and upper bounds of the concrete expansion under irradiation, and check if the scatter in the simulated results matches the one found in experiments. The numerical and experimental results will be compared in terms of expansion and loss of mechanical stiffness and strength. Both effects should be captured accordingly by the model to validate it. Once the model has been validated on these two experiments, it can be applied to simulate concrete from nuclear power plants. To do so, the materials used in these concrete must be as well characterized as possible. The main parameters required are the mechanical properties of each constituent in the concrete (aggregates, cement paste), namely the elastic modulus, the creep properties, the tensile and compressive strength, the thermal expansion coefficient, and the drying shrinkage. These can be either measured experimentally, estimated from the initial composition in the case of cement paste, or back-calculated from mechanical tests on concrete. If some

  9. AFDM: An Advanced Fluid-Dynamics Model

    SciTech Connect

    Bohl, W.R.; Parker, F.R. ); Wilhelm, D. . Inst. fuer Neutronenphysik und Reaktortechnik); Berthier, J. ); Goutagny, L. . Inst. de Protection et de Surete Nucleaire); Ninokata,

    1990-09-01

    AFDM, or the Advanced Fluid-Dynamics Model, is a computer code that investigates new approaches simulating the multiphase-flow fluid-dynamics aspects of severe accidents in fast reactors. The AFDM formalism starts with differential equations similar to those in the SIMMER-II code. These equations are modified to treat three velocity fields and supplemented with a variety of new models. The AFDM code has 12 topologies describing what material contacts are possible depending on the presence or absence of a given material in a computational cell, on the dominant liquid, and on the continuous phase. Single-phase, bubbly, churn-turbulent, cellular, and dispersed flow regimes are permitted for the pool situations modeled. Virtual mass terms are included for vapor in liquid-continuous flow. Interfacial areas between the continuous and discontinuous phases are convected to allow some tracking of phenomenological histories. Interfacial areas are also modified by models of nucleation, dynamic forces, turbulence, flashing, coalescence, and mass transfer. Heat transfer is generally treated using engineering correlations. Liquid-vapor phase transitions are handled with the nonequilibrium, heat-transfer-limited model, whereas melting and freezing processes are based on equilibrium considerations. Convection is treated using a fractional-step method of time integration, including a semi-implicit pressure iteration. A higher-order differencing option is provided to control numerical diffusion. The Los Alamos SESAME equation-of-state has been implemented using densities and temperatures as the independent variables. AFDM programming has vectorized all computational loops consistent with the objective of producing an exportable code. 24 refs., 4 figs.

  10. Nonlinear Dynamic Models in Advanced Life Support

    NASA Technical Reports Server (NTRS)

    Jones, Harry

    2002-01-01

    To facilitate analysis, ALS systems are often assumed to be linear and time invariant, but they usually have important nonlinear and dynamic aspects. Nonlinear dynamic behavior can be caused by time varying inputs, changes in system parameters, nonlinear system functions, closed loop feedback delays, and limits on buffer storage or processing rates. Dynamic models are usually cataloged according to the number of state variables. The simplest dynamic models are linear, using only integration, multiplication, addition, and subtraction of the state variables. A general linear model with only two state variables can produce all the possible dynamic behavior of linear systems with many state variables, including stability, oscillation, or exponential growth and decay. Linear systems can be described using mathematical analysis. Nonlinear dynamics can be fully explored only by computer simulations of models. Unexpected behavior is produced by simple models having only two or three state variables with simple mathematical relations between them. Closed loop feedback delays are a major source of system instability. Exceeding limits on buffer storage or processing rates forces systems to change operating mode. Different equilibrium points may be reached from different initial conditions. Instead of one stable equilibrium point, the system may have several equilibrium points, oscillate at different frequencies, or even behave chaotically, depending on the system inputs and initial conditions. The frequency spectrum of an output oscillation may contain harmonics and the sums and differences of input frequencies, but it may also contain a stable limit cycle oscillation not related to input frequencies. We must investigate the nonlinear dynamic aspects of advanced life support systems to understand and counter undesirable behavior.

  11. Modeling of advanced fossil fuel power plants

    NASA Astrophysics Data System (ADS)

    Zabihian, Farshid

    The first part of this thesis deals with greenhouse gas (GHG) emissions from fossil fuel-fired power stations. The GHG emission estimation from fossil fuel power generation industry signifies that emissions from this industry can be significantly reduced by fuel switching and adaption of advanced power generation technologies. In the second part of the thesis, steady-state models of some of the advanced fossil fuel power generation technologies are presented. The impacts of various parameters on the solid oxide fuel cell (SOFC) overpotentials and outputs are investigated. The detail analyses of operation of the hybrid SOFC-gas turbine (GT) cycle when fuelled with methane and syngas demonstrate that the efficiencies of the cycles with and without anode exhaust recirculation are close, but the specific power of the former is much higher. The parametric analysis of the performance of the hybrid SOFC-GT cycle indicates that increasing the system operating pressure and SOFC operating temperature and fuel utilization factor improves cycle efficiency, but the effects of the increasing SOFC current density and turbine inlet temperature are not favourable. The analysis of the operation of the system when fuelled with a wide range of fuel types demonstrates that the hybrid SOFC-GT cycle efficiency can be between 59% and 75%, depending on the inlet fuel type. Then, the system performance is investigated when methane as a reference fuel is replaced with various species that can be found in the fuel, i.e., H2, CO2, CO, and N 2. The results point out that influence of various species can be significant and different for each case. The experimental and numerical analyses of a biodiesel fuelled micro gas turbine indicate that fuel switching from petrodiesel to biodiesel can influence operational parameters of the system. The modeling results of gas turbine-based power plants signify that relatively simple models can predict plant performance with acceptable accuracy. The unique

  12. Recent advances and applications of probabilistic topic models

    NASA Astrophysics Data System (ADS)

    Wood, Ian

    2014-12-01

    I present here an overview of recent advances in probabilistic topic modelling and related Bayesian graphical models as well as some of their more atypical applications outside of their home: text analysis. These techniques allow the modelling of high dimensional count vectors with strong correlations. With such data, simply calculating a correlation matrix is infeasible. Probabilistic topic models address this using mixtures of multinomials estimated via Bayesian inference with Dirichlet priors. The use of conjugate priors allows for efficient inference, and these techniques scale well to data sets with many millions of vectors. The first of these techniques to attract significant attention was Latent Dirichlet Allocation (LDA) [1, 2]. Numerous extensions and adaptations of LDA have been proposed: non-parametric models; assorted models incorporating authors, sentiment and other features; models regularised through the use of extra metadata or extra priors on topic structure, and many more [3]. They have become widely used in the text analysis and population genetics communities, with a number of compelling applications. These techniques are not restricted to text analysis, however, and can be applied to other types of data which can be sensibly discretised and represented as counts of labels/properties/etc. LDA and it's variants have been used to find patterns in data from diverse areas of inquiry, including genetics, plant physiology, image analysis, social network analysis, remote sensing and astrophysics. Nonetheless, it is relatively recently that probabilistic topic models have found applications outside of text analysis, and to date few such applications have been considered. I suggest that there is substantial untapped potential for topic models and models inspired by or incorporating topic models to be fruitfully applied, and outline the characteristics of systems and data for which this may be the case.

  13. Advanced Thermoplastic Polymers and Additive Manufacturing Applied to ISS Columbus Toolbox: Lessons Learnt and Results

    NASA Astrophysics Data System (ADS)

    Ferrino, Marinella; Secondo, Ottaviano; Sabbagh, Amir; Della Sala, Emilio

    2014-06-01

    In the frame of the International Space Station (ISS) Exploitation Program a new toolbox has been realized by TAS-I to accommodate the tools currently in use on the ISS Columbus Module utilizing full-scale prototypes obtained with 3D rapid prototyping. The manufacturing of the flight hardware by means of advanced thermoplastic polymer UL TEM 9085 and additive manufacturing Fused Deposition Modelling (FDM) technology represent innovative elements. In this paper, the results achieved and the lessons learned are analyzed to promote future technology know-how. The acquired experience confirmed that the additive manufacturing process allows to save time/cost and to realize new shapes/features to introduce innovation in products and future design processes for space applications.

  14. The Path to Sustainable Nuclear Energy. Basic and Applied Research Opportunities for Advanced Fuel Cycles

    SciTech Connect

    Finck, P.; Edelstein, N.; Allen, T.; Burns, C.; Chadwick, M.; Corradini, M.; Dixon, D.; Goff, M.; Laidler, J.; McCarthy, K.; Moyer, B.; Nash, K.; Navrotsky, A.; Oblozinsky, P.; Pasamehmetoglu, K.; Peterson, P.; Sackett, J.; Sickafus, K. E.; Tulenko, J.; Weber, W.; Morss, L.; Henry, G.

    2005-09-01

    fuel cycle Development of advanced tools for designing reactors with reduced margins and lower costs ? Long-term nuclear reactor development requires basic science breakthroughs: Understanding of materials behavior under extreme environmental conditions Creation of new, efficient, environmentally benign chemical separations methods Modeling and simulation to improve nuclear reaction cross-section data, design new materials and separation system, and propagate uncertainties within the fuel cycle Improvement of proliferation resistance by strengthening safeguards technologies and decreasing the attractiveness of nuclear materials A series of translational tools is proposed to advance the AFCI objectives and to bring the basic science concepts and processes promptly into the technological sphere. These tools have the potential to revolutionize the approach to nuclear engineering R&D by replacing lengthy experimental campaigns with a rigorous approach based on modeling, key fundamental experiments, and advanced simulations.

  15. Methods for model selection in applied science and engineering.

    SciTech Connect

    Field, Richard V., Jr.

    2004-10-01

    Mathematical models are developed and used to study the properties of complex systems and/or modify these systems to satisfy some performance requirements in just about every area of applied science and engineering. A particular reason for developing a model, e.g., performance assessment or design, is referred to as the model use. Our objective is the development of a methodology for selecting a model that is sufficiently accurate for an intended use. Information on the system being modeled is, in general, incomplete, so that there may be two or more models consistent with the available information. The collection of these models is called the class of candidate models. Methods are developed for selecting the optimal member from a class of candidate models for the system. The optimal model depends on the available information, the selected class of candidate models, and the model use. Classical methods for model selection, including the method of maximum likelihood and Bayesian methods, as well as a method employing a decision-theoretic approach, are formulated to select the optimal model for numerous applications. There is no requirement that the candidate models be random. Classical methods for model selection ignore model use and require data to be available. Examples are used to show that these methods can be unreliable when data is limited. The decision-theoretic approach to model selection does not have these limitations, and model use is included through an appropriate utility function. This is especially important when modeling high risk systems, where the consequences of using an inappropriate model for the system can be disastrous. The decision-theoretic method for model selection is developed and applied for a series of complex and diverse applications. These include the selection of the: (1) optimal order of the polynomial chaos approximation for non-Gaussian random variables and stationary stochastic processes, (2) optimal pressure load model to be

  16. Advances in NLTE Modeling for Integrated Simulations

    SciTech Connect

    Scott, H A; Hansen, S B

    2009-07-08

    The last few years have seen significant progress in constructing the atomic models required for non-local thermodynamic equilibrium (NLTE) simulations. Along with this has come an increased understanding of the requirements for accurately modeling the ionization balance, energy content and radiative properties of different elements for a wide range of densities and temperatures. Much of this progress is the result of a series of workshops dedicated to comparing the results from different codes and computational approaches applied to a series of test problems. The results of these workshops emphasized the importance of atomic model completeness, especially in doubly excited states and autoionization transitions, to calculating ionization balance, and the importance of accurate, detailed atomic data to producing reliable spectra. We describe a simple screened-hydrogenic model that calculates NLTE ionization balance with surprising accuracy, at a low enough computational cost for routine use in radiation-hydrodynamics codes. The model incorporates term splitting, {Delta}n = 0 transitions, and approximate UTA widths for spectral calculations, with results comparable to those of much more detailed codes. Simulations done with this model have been increasingly successful at matching experimental data for laser-driven systems and hohlraums. Accurate and efficient atomic models are just one requirement for integrated NLTE simulations. Coupling the atomic kinetics to hydrodynamics and radiation transport constrains both discretizations and algorithms to retain energy conservation, accuracy and stability. In particular, the strong coupling between radiation and populations can require either very short timesteps or significantly modified radiation transport algorithms to account for NLTE material response. Considerations such as these continue to provide challenges for NLTE simulations.

  17. Clinically applied models of bone regeneration in tissue engineering research.

    PubMed

    Einhorn, T A

    1999-10-01

    The development of new strategies for the engineering of bone regeneration requires appropriate model systems. Selection of the best model for testing a new technology depends on a host of factors. In general, the best model system is the one which most closely mimics the clinical situation for which this technology is being developed, will not heal spontaneously unless the technology is used, and will not heal when another technology is used if that technology is less advanced than the one being tested. For the purposes of developing new strategies for bone regeneration, systems which can be considered include those which model normal fracture healing, the segmental loss of bone or critical size defects, and various forms of nonunions in which fracture healing is perturbed either by mechanical, metabolic, or neurologic means. Careful experimental design and selection of the appropriate model system will enhance scientific efforts in bone regeneration research.

  18. Advanced Combustion Modeling for Complex Turbulent Flows

    NASA Technical Reports Server (NTRS)

    Ham, Frank Stanford

    2005-01-01

    The next generation of aircraft engines will need to pass stricter efficiency and emission tests. NASA's Ultra-Efficient Engine Technology (UEET) program has set an ambitious goal of 70% reduction of NO(x) emissions and a 15% increase in fuel efficiency of aircraft engines. We will demonstrate the state-of-the-art combustion tools developed a t Stanford's Center for Turbulence Research (CTR) as part of this program. In the last decade, CTR has spear-headed a multi-physics-based combustion modeling program. Key technologies have been transferred to the aerospace industry and are currently being used for engine simulations. In this demo, we will showcase the next-generation combustion modeling tools that integrate a very high level of detailed physics into advanced flow simulation codes. Combustor flows involve multi-phase physics with liquid fuel jet breakup, evaporation, and eventual combustion. Individual components of the simulation are verified against complex test cases and show excellent agreement with experimental data.

  19. Advanced Combustion Modeling for Complex Turbulent Flows

    NASA Technical Reports Server (NTRS)

    Ham, Frank Stanford

    2005-01-01

    The next generation of aircraft engines will need to pass stricter efficiency and emission tests. NASA's Ultra-Efficient Engine Technology (UEET) program has set an ambitious goal of 70% reduction of NO(x) emissions and a 15% increase in fuel efficiency of aircraft engines. We will demonstrate the state-of-the-art combustion tools developed a t Stanford's Center for Turbulence Research (CTR) as part of this program. In the last decade, CTR has spear-headed a multi-physics-based combustion modeling program. Key technologies have been transferred to the aerospace industry and are currently being used for engine simulations. In this demo, we will showcase the next-generation combustion modeling tools that integrate a very high level of detailed physics into advanced flow simulation codes. Combustor flows involve multi-phase physics with liquid fuel jet breakup, evaporation, and eventual combustion. Individual components of the simulation are verified against complex test cases and show excellent agreement with experimental data.

  20. Scalable Iterative Solvers Applied to 3D Parallel Simulation of Advanced Semiconductor Devices

    NASA Astrophysics Data System (ADS)

    García-Loureiro, A. J.; Aldegunde, M.; Seoane, N.

    2009-08-01

    We have studied the performance of a preconditioned iterative solver to speed up a 3D semiconductor device simulator. Since 3D simulations necessitate large computing resources, the choice of algorithms and their parameters become of utmost importance. This code uses a density gradient drift-diffusion semiconductor transport model based on the finite element method which is one of the most general and complex discretisation techniques. It has been implemented for a distributed memory multiprocessor environment using the Message Passing Interface (MPI) library. We have applied this simulator to a 67 nm effective gate length Si MOSFET.

  1. Advance finite element modeling of rotor blade aeroelasticity

    NASA Technical Reports Server (NTRS)

    Straub, F. K.; Sangha, K. B.; Panda, B.

    1994-01-01

    An advanced beam finite element has been developed for modeling rotor blade dynamics and aeroelasticity. This element is part of the Element Library of the Second Generation Comprehensive Helicopter Analysis System (2GCHAS). The element allows modeling of arbitrary rotor systems, including bearingless rotors. It accounts for moderately large elastic deflections, anisotropic properties, large frame motion for maneuver simulation, and allows for variable order shape functions. The effects of gravity, mechanically applied and aerodynamic loads are included. All kinematic quantities required to compute airloads are provided. In this paper, the fundamental assumptions and derivation of the element matrices are presented. Numerical results are shown to verify the formulation and illustrate several features of the element.

  2. 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.

  3. Advances in Modelling of Valley Glaciers

    NASA Astrophysics Data System (ADS)

    Adhikari, Surendra

    For glaciological conditions typical of valley glaciers, the central idea of this research lies in understanding the effects of high-order mechanics and parameterizing these for simpler dynamical and statistical methods in glaciology. As an effective tool for this, I formulate a new brand of dynamical models that describes distinct physical processes of deformational flow. Through numerical simulations of idealized glacier domains, I calculate empirical correction factors to capture the effects of longitudinal stress gradients and lateral drag for simplified dynamical models in the plane-strain regime. To get some insights into real glacier dynamics, I simulate Haig Glacier in the Canadian Rocky Mountains. As geometric effects overshadow dynamical effects in glacier retreat scenarios, it appears that high-order physics are not very important for Haig Glacier, particularly for evaluating its fate. Indeed, high-order and reduced models all predict that Haig Glacier ceases to exist by about AD2080 under ongoing climate warming. This finding regarding the minimal role of high-order physics may not be broadly valid, as it is not true in advance scenarios at Haig Glacier and it may not be representative of other glaciological settings. Through a 'bulk' parameterization of high-order physics, geometric and climatic settings, sliding conditions, and transient effects, I also provide new insights into the volume-area relation, a widely used statistical method for estimating glacier volume. I find a steady-state power-law exponent of 1:46, which declines systematically to 1:38 after 100 years of sustained retreat, in good accord with the observations. I recommend more accurate scaling relations through characterization of individual glacier morphology and degree of climatic disequilibrium. This motivates a revision of global glacier volume estimates, of some urgency in sea level rise assessments.

  4. Advanced Modeling, Simulation and Analysis (AMSA) Capability Roadmap Progress Review

    NASA Technical Reports Server (NTRS)

    Antonsson, Erik; Gombosi, Tamas

    2005-01-01

    Contents include the following: NASA capability roadmap activity. Advanced modeling, simulation, and analysis overview. Scientific modeling and simulation. Operations modeling. Multi-special sensing (UV-gamma). System integration. M and S Environments and Infrastructure.

  5. Hopfield Model Applied to Vowel and Consonant Discrimination

    DTIC Science & Technology

    1986-06-03

    Speed Up Network Computations 26 LIST OF TABLES Table No. Page I Word Pairs by Single Speaker 20 vn HOPFIELD MODEL APPLIED TO VOWEL AND...describes some computer simulation results on vowel and consonant dis- crimination based on this associative memory model. Section 2 of this report...1 1200 2400 HERTZ 3600 4800 Figure 4. Smoothed spectral envelope function for vowel in "vill.’ 0 (43 Errors

  6. Applying knowledge compilation techniques to model-based reasoning

    NASA Technical Reports Server (NTRS)

    Keller, Richard M.

    1991-01-01

    Researchers in the area of knowledge compilation are developing general purpose techniques for improving the efficiency of knowledge-based systems. In this article, an attempt is made to define knowledge compilation, to characterize several classes of knowledge compilation techniques, and to illustrate how some of these techniques can be applied to improve the performance of model-based reasoning systems.

  7. Applying the Flipped Classroom Model to English Language Arts Education

    ERIC Educational Resources Information Center

    Young, Carl A., Ed.; Moran, Clarice M., Ed.

    2017-01-01

    The flipped classroom method, particularly when used with digital video, has recently attracted many supporters within the education field. Now more than ever, language arts educators can benefit tremendously from incorporating flipped classroom techniques into their curriculum. "Applying the Flipped Classroom Model to English Language Arts…

  8. Knowledge Growth: Applied Models of General and Individual Knowledge Evolution

    ERIC Educational Resources Information Center

    Silkina, Galina Iu.; Bakanova, Svetlana A.

    2016-01-01

    The article considers the mathematical models of the growth and accumulation of scientific and applied knowledge since it is seen as the main potential and key competence of modern companies. The problem is examined on two levels--the growth and evolution of objective knowledge and knowledge evolution of a particular individual. Both processes are…

  9. Guidelines for applying the Composite Specification Model (CSM)

    NASA Technical Reports Server (NTRS)

    Agresti, William

    1987-01-01

    The Composite Specification Model (CSM) is an approach to representing software requirements. Guidelines are provided for applying CSM and developing each of the three descriptive views of the software: the contextual view, using entities and relationships; the dynamic view, using states and transitions; and the function view, using data flows and processes. Using CSM results in a software specification document, which is outlined.

  10. Applying a Classroom Process Model to Instructional Evaluation.

    ERIC Educational Resources Information Center

    Leinhardt, Gaea

    Variations in classroom instruction were observed, and related to student achievement in reading and mathematics. A six-construct model was applied to data on students and instructional practices in sixty second grade classrooms at nine geographic sites, seven of which were sponsored by Project Follow-Through. The constructs were: (l) initial…

  11. Applying computer simulation models as learning tools in fishery management

    USGS Publications Warehouse

    Johnson, B.L.

    1995-01-01

    Computer models can be powerful tools for addressing many problems in fishery management, but uncertainty about how to apply models and how they should perform can lead to a cautious approach to modeling. Within this approach, we expect models to make quantitative predictions but only after all model inputs have been estimated from empirical data and after the model has been tested for agreement with an independent data set. I review the limitations to this approach and show how models can be more useful as tools for organizing data and concepts, learning about the system to be managed, and exploring management options. Fishery management requires deciding what actions to pursue to meet management objectives. Models do not make decisions for us but can provide valuable input to the decision-making process. When empirical data are lacking, preliminary modeling with parameters derived from other sources can help determine priorities for data collection. When evaluating models for management applications, we should attempt to define the conditions under which the model is a useful, analytical tool (its domain of applicability) and should focus on the decisions made using modeling results, rather than on quantitative model predictions. I describe an example of modeling used as a learning tool for the yellow perch Perca flavescens fishery in Green Bay, Lake Michigan.

  12. Socio-optics: optical knowledge applied in modeling social phenomena

    NASA Astrophysics Data System (ADS)

    Chisleag, Radu; Chisleag Losada, Ioana-Roxana

    2011-05-01

    The term "Socio-optics" (as a natural part of Socio-physics), is rather not found in literature or at Congresses. In Optics books, there are not made references to optical models applied to explain social phenomena, in spite of Optics relying on the duality particle-wave which seems convenient to model relationships among society and its members. The authors, who have developed a few models applied to explain social phenomena based on knowledge in Optics, along with a few other models applying, in Social Sciences, knowledge from other branches of Physics, give their own examples of such optical models, f. e., of relationships among social groups and their sub-groups, by using kowledge from partially coherent optical phenomena or to explain by tunnel effect, the apparently impossible penetration of social barriers by individuals. They consider that the term "Socio-optics" may come to life. There is mentioned the authors' expertise in stimulating Socio-optics approach by systematically asking students taken courses in Optics to find applications of the newly got Wave and Photon Optics knowledge, to model social and even everyday life phenomena, eventually engaging in such activities other possibly interested colleagues.

  13. Advanced behavioral applications in schools: A review of R. Douglas Greer's designing teaching strategies: An applied behavior analysis systems approach

    PubMed Central

    Moxley, Roy A.

    2004-01-01

    R. Douglas Greer1s Designing Teaching Strategies is an important book directed to advanced students in applied behavior analysis for classrooms. This review presents some of the striking features of the Comprehensive Applied Behavior Analysis to Schooling (CABAS®) program and the individualized instruction that the book advances. These include its instruction in literacy, its use of graphing, and its flexibility in systematic organization. Although its readability could be improved, this book has much to recommend it in an approach that has acquired an international following. PMID:22477295

  14. Advances and innovations in models of mantle convection

    NASA Astrophysics Data System (ADS)

    Kellogg, L. H.

    2002-12-01

    More than three decades ago, Turcotte and Oxburgh published their landmark paper showing how mantle convection drives motion of the continents, with the cold thermal boundary layers representing the surface plates. Since that time, models of mantle convection have made remarkable advancements and have been applied to the interiors of the terrestrial planets and moons, with many fundamental contributions by Don Turcotte and inspired by his work. Here, I will address some of the recent advances and innovations in mantle convection, with special emphasis on ideas emerging from the application of nonlinear dynamics and chemical geodynamics. Numerical models of convection, combined with observations from heat flow, cosmochemistry, and mantle geochemistry, provide constraints on models of the composition and structure of the mantle. Geochemical and heat flow observations appear to require long-lived heterogeneity in the mantle, while numerical models of convection generally exhibit rapid mixing, creating a distinctive ``marble-cake'' texture of recycled lithosphere. A variety of models have been suggested to reconcile these diverse inferences about mantle dynamics and structure from seemingly contradictory geochemical and geophysical observations. One straightforward explanation of combined geochemical and geophysical observations is a compositionally heterogeneous lowermost mantle. A difference between the composition of the MORB source and the composition of the deep mantle is also consistent with estimates of the properties of perovskite at high pressures and temperatures. Heterogeneity in the lower mantle may take the form of a hot abyssal layer of variable thickness starting at the mid-mantle or in the lowermost mantle, or may consist of "blobs" in the lower mantle. The hot abyssal layer model has an advantage over the blob model, because hot, neutrally buoyant blobs are unlikely to persist for the long times required by chemical geodynamics. Chemical geodynamics

  15. Applying Particle Tracking Model In The Coastal Modeling System

    DTIC Science & Technology

    2011-01-01

    Rev. 8-98) Prescribed by ANSI Std Z39-18 ERDC/CHL CHETN-IV-78 January 2011 2 Figure 1. CMS domain, grid, and bathymetry . CMS-Flow is driven by...through the simulation. At the end of the simulation, about 65 percent of the released clay particles are considered “ dead ,” ERDC/CHL CHETN-IV-78 January...2011 11 which means that they are either permanently buried at the sea bed or have moved out of the model domain. Figure 11. Specifications of

  16. New advances for modelling the debris avalanches

    NASA Astrophysics Data System (ADS)

    Cuomo, Sabatino; Cascini, Leonardo; Pastor, Manuel; Castorino, Giuseppe Claudio

    2013-04-01

    Flow-like landslides are a major global hazard and they occur worldwide causing a large number of casualties, significant structural damages to property and infrastructures as well as economic losses. When involving open slopes, these landslides often occur in triangular source areas where initial slides turn into avalanches through further failures and/or eventual soil entrainment. This paper deals with the numerical modelling of the propagation stage of debris avalanches which provides information such as the propagation pattern of the mobilized material, its velocity, thickness and run-out distance. In the paper, a "depth integrated" model is used which allows: i) adequately taking into account the irregular topography of real slopes which greatly affect the propagation stage and ii) using a less time consuming model than fully 3D approaches. The used model is named "GeoFlow_SPH" and it was formerly applied to theoretical, experimental and real case histories (Pastor et al., 2009; Cascini et al., 2012). In this work the behavior of debris avalanches is analyzed with special emphasis on the apical angle, one of the main features of this type of landslide, in relation to soil rheology, hillslope geometry and features of triggering area. Furthermore, the role of erosion has been investigated with reference to the uppermost parts of open slopes with a different steepness. These analyses are firstly carried out for simplified benchmark slopes, using both water-like materials (with no shear strength) and debris type materials. Then, three important case studies of Campania region (Cervinara, Nocera Inferiore e Sarno) are analyzed where debris avalanches involved pyroclastic soils originated from the eruptive products of Vesusius volcano. The results achieved for both benchmark slopes and real case histories outline the key role played by the erosion on the whole propagation stage of debris avalanches. The results are particularly satisfactory since they indicate the

  17. Rapid prototyping and AI programming environments applied to payload modeling

    NASA Technical Reports Server (NTRS)

    Carnahan, Richard S., Jr.; Mendler, Andrew P.

    1987-01-01

    This effort focused on using artificial intelligence (AI) programming environments and rapid prototyping to aid in both space flight manned and unmanned payload simulation and training. Significant problems addressed are the large amount of development time required to design and implement just one of these payload simulations and the relative inflexibility of the resulting model to accepting future modification. Results of this effort have suggested that both rapid prototyping and AI programming environments can significantly reduce development time and cost when applied to the domain of payload modeling for crew training. The techniques employed are applicable to a variety of domains where models or simulations are required.

  18. Computer-aided modeling applied to microengineered pressure sensors

    NASA Astrophysics Data System (ADS)

    Georgaras, C.; Samaan, Noel D.

    1998-04-01

    The development of miniaturized diaphragm structures is highly significant to the successful realization of many microengineered devices. Most industrial designs of physical sensors are now based upon detailed finite element modeling of the mechanical microstructures using software currently available for conventional mechanics. This paper investigates the effects of miniaturization on corrugated diaphragm structures through the use of advanced computer modeling and simulation techniques. By developing detailed models of the diaphragm structures using commercial finite element analysis software it is possible to investigate the effects on diaphragm performance when diaphragms are scaled from a macro level (eg. 10 mm diameter) down to a micro level (< 1 mm diameter). Case studies are presented and comparisons are made with research work published by other workers. With subsequent sensitivity analysis it is possible to explore the critical design parameters of the microengineered diaphragms, and parameterize the diaphragm such that its performance will be compensated to some degree from limitations imposed by processing parameters.

  19. Applying the transtheoretical model to health care proxy completion.

    PubMed

    Finnell, Deborah S; Wu, Yow-Wu Bill; Jezewski, Mary Ann; Meeker, Mary Ann; Sessanna, Loralee; Lee, Jongwon

    2011-01-01

    For many, an important health decision is whether or not to document end-of-life wishes using an advance directive (e.g., health care proxy). To date, interventions targeting this health behavior have had little effect on increasing advance directive completion rates. Health behavior models, such as the transtheoretical model (TTM) could be useful for understanding the health decision-making processes used along a continuum, from no intention to complete an advance directive to completing one and discussing it with an appointed advocate. To explore the applicability of the TTM for a previously understudied health behavior-completing a health care proxy (HCP). Four established TTM measures for completing a HCP (stages of change, processes of change, decisional balance, and self-efficacy) were administered to 566 adults with coverage from 1 of 2 health insurance companies. Separate analyses of variance were used to test the relationships between the independent variable (stages of change) and dependent variables (processes of change, decisional balance, self-efficacy scores). Consistent with other TTM research both the experiential and the behavioral processes of change revealed the lowest scores in the precontemplation stage peaking in the preparation stage. The pattern of pros and cons was replicated from previous TTM studies, with the 2 scores crossing over just prior to the preparation stage. Self-efficacy scores incrementally increased across the stages of change with the largest effect evident from the precontemplation to preparation stage. The models developed from this study can be used to guide the development of stage-based interventions for promoting health care proxy completion.

  20. Applying Mathematical Optimization Methods to an ACT-R Instance-Based Learning Model.

    PubMed

    Said, Nadia; Engelhart, Michael; Kirches, Christian; Körkel, Stefan; Holt, Daniel V

    2016-01-01

    Computational models of cognition provide an interface to connect advanced mathematical tools and methods to empirically supported theories of behavior in psychology, cognitive science, and neuroscience. In this article, we consider a computational model of instance-based learning, implemented in the ACT-R cognitive architecture. We propose an approach for obtaining mathematical reformulations of such cognitive models that improve their computational tractability. For the well-established Sugar Factory dynamic decision making task, we conduct a simulation study to analyze central model parameters. We show how mathematical optimization techniques can be applied to efficiently identify optimal parameter values with respect to different optimization goals. Beyond these methodological contributions, our analysis reveals the sensitivity of this particular task with respect to initial settings and yields new insights into how average human performance deviates from potential optimal performance. We conclude by discussing possible extensions of our approach as well as future steps towards applying more powerful derivative-based optimization methods.

  1. Models for Curricular Materials Development: Combining Applied Development Processes with Theory

    NASA Astrophysics Data System (ADS)

    Appleton, James; Lawrenz, Frances; Craft, Elaine; Cudmore, Wynn; Hall, Jim; Waintraub, Jack

    2007-12-01

    Developing curricular materials for technical and vocational education is particularly challenging because of the comprehensive requirements for technical education and the rapidity with which technical positions are evolving. Well-educated employees are expected to have general communication, reasoning, problem-solving, and behavioral skills in addition to occupation-specific technical knowledge. Furthermore, technical and vocational education materials must meet the needs of various contexts each with its own unique array of factors which must be accommodated. To assist in the process of materials development, this paper presents a comprehensive and contextualized model as a guide for curricular developers. This model was formed through the synthesis of two theoretical and four applied models, with the outline of the applied models occurring as part of a national evaluation of the National Science Foundation's Advanced Technological Education Program. Examples illuminating the elements of the template are provided.

  2. Applying Model Based Systems Engineering to NASA's Space Communications Networks

    NASA Technical Reports Server (NTRS)

    Bhasin, Kul; Barnes, Patrick; Reinert, Jessica; Golden, Bert

    2013-01-01

    System engineering practices for complex systems and networks now require that requirement, architecture, and concept of operations product development teams, simultaneously harmonize their activities to provide timely, useful and cost-effective products. When dealing with complex systems of systems, traditional systems engineering methodology quickly falls short of achieving project objectives. This approach is encumbered by the use of a number of disparate hardware and software tools, spreadsheets and documents to grasp the concept of the network design and operation. In case of NASA's space communication networks, since the networks are geographically distributed, and so are its subject matter experts, the team is challenged to create a common language and tools to produce its products. Using Model Based Systems Engineering methods and tools allows for a unified representation of the system in a model that enables a highly related level of detail. To date, Program System Engineering (PSE) team has been able to model each network from their top-level operational activities and system functions down to the atomic level through relational modeling decomposition. These models allow for a better understanding of the relationships between NASA's stakeholders, internal organizations, and impacts to all related entities due to integration and sustainment of existing systems. Understanding the existing systems is essential to accurate and detailed study of integration options being considered. In this paper, we identify the challenges the PSE team faced in its quest to unify complex legacy space communications networks and their operational processes. We describe the initial approaches undertaken and the evolution toward model based system engineering applied to produce Space Communication and Navigation (SCaN) PSE products. We will demonstrate the practice of Model Based System Engineering applied to integrating space communication networks and the summary of its

  3. Modeling of advanced discharges for TPX

    SciTech Connect

    St. John, H.E.; Lin-Liu, Y.R.; Politzer, P.A.; Chiu, S.C.; Chu, M.S.; Miller, R.L.; Turnbull, A.D.

    1995-10-06

    We describe the results of the Tokamak Physics Experiment (TPX) Scenario Modeling task. We investigated the achievement of high performance advanced tokamak operating modes in TPX through current and pressure profile shaping using fast wave (FW), lower hybrid (LH), and neutral beam (NB) heating and current drive capabilities. As part of the task, the Aries-I and negative central shear (NCS) discharges were re-examined using computer codes. We have confirmed that the Aries-I scenario yields a magnetohydrodynamic (MHD)/transport steady- state with a very small amount ({le} 10 kA) of inductively driven current. The NCS scenario with 61 MHz FW current drive was found to be unworkable due to third harmonic ion absorption. A revised NCS discharge using 34 MHz FW but otherwise identical to the original discharge was investigated and found to be stable to n = 1,2 ideal kink modes with a wall at r/r{sub a} {le} 1.2. Two new scenarios chosen to complement the original modeling were then developed. The first was a VH-mode discharge and the second was an NCS discharge with an L-mode edge. The VH-mode discharge was found to be marginally stable to n = 1,2,3 ideal kink and ballooning modes at {beta}{sub T} {approximately} 2.7% with a conducting wall at r/r{sub a} = 1.1. Both discharges were found to be unstable to n = 1 resistive wall modes. The 2.2% case has a window of stability at 1.27 {le} r/r{sub a} {le} 1.35 when uniform toroidal rotation at {approximately} 1000 km/sec is assumed. The high toroidal rotation speed required to stabilize the VH-mode mode discharge should be investigated in the future and MHD equilibrium calculations which include the associated centrifugal force should be used. We have found that modeling such a discharge assuming experimentally measured profiles is not possible due to the transient nature of experimentally created NCS discharges.

  4. Expansion of Perturbation Theory Applied to Shim Rotation Automation of the Advanced Test Reactor

    NASA Astrophysics Data System (ADS)

    Peterson, Joshua Loren

    In 2007, the Department of Energy (DOE) declared the Advanced Test Reactor (ATR) a National Scientific User Facility (NSUF). This declaration expanded the focus of the ATR to include diversified classes of academic and industrial experiments. An essential part of the new suite of more accurate and flexible codes being deployed to support the NSUF is their ability to predict reactor behavior at startup, particularly the position of the outer shim control cylinders (OSCC). The current method used for calculating the OSCC positions during a cycle startup utilizes a heuristic trial and error approach that is impractical with the computationally intensive reactor physics tools, such as NEWT. It is therefore desirable that shim rotation prediction for startup be automated. Shim rotation prediction with perturbation theory was chosen to be investigated as one method for use with startup calculation automation. A modified form of first order perturbation theory, called phase space interpolated perturbation theory, was developed to more accurately model shim rotation prediction. Shim rotation prediction is just one application for this new modified form of perturbation theory. Phase space interpolated perturbation theory can be used on any application where the range of change to the system is known a priori, but the magnitude of change is not known. A cubic regression method was also developed to automate shim rotation prediction by using only forward solutions to the transport equation.

  5. Size-specific sensitivity: Applying a new structured population model

    SciTech Connect

    Easterling, M.R.; Ellner, S.P.; Dixon, P.M.

    2000-03-01

    Matrix population models require the population to be divided into discrete stage classes. In many cases, especially when classes are defined by a continuous variable, such as length or mass, there are no natural breakpoints, and the division is artificial. The authors introduce the integral projection model, which eliminates the need for division into discrete classes, without requiring any additional biological assumptions. Like a traditional matrix model, the integral projection model provides estimates of the asymptotic growth rate, stable size distribution, reproductive values, and sensitivities of the growth rate to changes in vital rates. However, where the matrix model represents the size distributions, reproductive value, and sensitivities as step functions (constant within a stage class), the integral projection model yields smooth curves for each of these as a function of individual size. The authors describe a method for fitting the model to data, and they apply this method to data on an endangered plant species, northern monkshood (Aconitum noveboracense), with individuals classified by stem diameter. The matrix and integral models yield similar estimates of the asymptotic growth rate, but the reproductive values and sensitivities in the matrix model are sensitive to the choice of stage classes. The integral projection model avoids this problem and yields size-specific sensitivities that are not affected by stage duration. These general properties of the integral projection model will make it advantageous for other populations where there is no natural division of individuals into stage classes.

  6. A general diagnostic model applied to language testing data.

    PubMed

    von Davier, Matthias

    2008-11-01

    Probabilistic models with one or more latent variables are designed to report on a corresponding number of skills or cognitive attributes. Multidimensional skill profiles offer additional information beyond what a single test score can provide, if the reported skills can be identified and distinguished reliably. Many recent approaches to skill profile models are limited to dichotomous data and have made use of computationally intensive estimation methods such as Markov chain Monte Carlo, since standard maximum likelihood (ML) estimation techniques were deemed infeasible. This paper presents a general diagnostic model (GDM) that can be estimated with standard ML techniques and applies to polytomous response variables as well as to skills with two or more proficiency levels. The paper uses one member of a larger class of diagnostic models, a compensatory diagnostic model for dichotomous and partial credit data. Many well-known models, such as univariate and multivariate versions of the Rasch model and the two-parameter logistic item response theory model, the generalized partial credit model, as well as a variety of skill profile models, are special cases of this GDM. In addition to an introduction to this model, the paper presents a parameter recovery study using simulated data and an application to real data from the field test for TOEFL Internet-based testing.

  7. Agrochemical fate models applied in agricultural areas from Colombia

    NASA Astrophysics Data System (ADS)

    Garcia-Santos, Glenda; Yang, Jing; Andreoli, Romano; Binder, Claudia

    2010-05-01

    The misuse application of pesticides in mainly agricultural catchments can lead to severe problems for humans and environment. Especially in developing countries where there is often found overuse of agrochemicals and incipient or lack of water quality monitoring at local and regional levels, models are needed for decision making and hot spots identification. However, the complexity of the water cycle contrasts strongly with the scarce data availability, limiting the number of analysis, techniques, and models available to researchers. Therefore there is a strong need for model simplification able to appropriate model complexity and still represent the processes. We have developed a new model so-called Westpa-Pest to improve water quality management of an agricultural catchment located in the highlands of Colombia. Westpa-Pest is based on the fully distributed hydrologic model Wetspa and a fate pesticide module. We have applied a multi-criteria analysis for model selection under the conditions and data availability found in the region and compared with the new developed Westpa-Pest model. Furthermore, both models were empirically calibrated and validated. The following questions were addressed i) what are the strengths and weaknesses of the models?, ii) which are the most sensitive parameters of each model?, iii) what happens with uncertainties in soil parameters?, and iv) how sensitive are the transfer coefficients?

  8. Modeling of Mechanical Properties of Advanced Nanostructured Ceramic Composites

    DTIC Science & Technology

    2010-03-15

    technical report 3. DATES COVERED (From - To) From Ol-Jan-2007 to 31 -Dec-2009 4. TITLE AND SUBTITLE Modeling of Mechanical Properties of Advanced ...for puj^Ux^ r^Wse_- dC5+rvioockd>v^ <JMT4MTLC4<JSI . 13. SUPPLEMENTARY NOTES 14. ABSTRACT Mechanical properties of advanced nanostructured...Modeling of Mechanical Properties of Advanced Nanostructured Ceramic Composites Program Officer: Larry Kabacoff CO-PI Information Number of Co-PIs

  9. The Ising Model Applied on Chronification of Pain

    PubMed Central

    2016-01-01

    This is a hypothesis-article suggesting an entirely new framework for understanding and treating longstanding pain. Most medical and psychological models are described with boxes and arrows. Such models are of little clinical and explanatory use when describing the phenomenon of chronification of pain due to unknown causes. To date no models that have been provided - and tested in a scientific satisfactory way - lays out a plan for specific assessment due to a specific causal explanation, and in the end serves the clinicians, patients and researcher with tools on how to address the specific pain condition to every individual pain patient's condition. By applying the Ising model (from physics) on the phenomenon of chronification of pain, one is able to detangle all these factors, and thus have a model that both suggests an explanation of the condition and outlines how one might target the treatment of chronic pain patients with the use of network science. PMID:26398917

  10. The Ising Model Applied on Chronification of Pain.

    PubMed

    Granan, Lars-Petter

    2016-01-01

    This is a hypothesis-article suggesting an entirely new framework for understanding and treating longstanding pain. Most medical and psychological models are described with boxes and arrows. Such models are of little clinical and explanatory use when describing the phenomenon of chronification of pain due to unknown causes. To date no models that have been provided - and tested in a scientific satisfactory way - lays out a plan for specific assessment due to a specific causal explanation, and in the end serves the clinicians, patients and researcher with tools on how to address the specific pain condition to every individual pain patient's condition. By applying the Ising model (from physics) on the phenomenon of chronification of pain, one is able to detangle all these factors, and thus have a model that both suggests an explanation of the condition and outlines how one might target the treatment of chronic pain patients with the use of network science.

  11. Applying generalized Padé approximants in analytic QCD models

    NASA Astrophysics Data System (ADS)

    Cvetič, Gorazd; Kögerler, Reinhart

    2011-09-01

    A method of resummation of truncated perturbation series, related to diagonal Padé approximants but giving results independent of the renormalization scale, was developed more than ten years ago by us with a view of applying it in perturbative QCD. We now apply this method in analytic QCD models, i.e., models where the running coupling has no unphysical singularities, and we show that the method has attractive features, such as a rapid convergence. The method can be regarded as a generalization of the scale-setting methods of Stevenson, Grunberg, and Brodsky-Lepage-Mackenzie. The method involves the fixing of various scales and weight coefficients via an auxiliary construction of diagonal Padé approximant. In low-energy QCD observables, some of these scales become sometimes low at high order, which prevents the method from being effective in perturbative QCD, where the coupling has unphysical singularities at low spacelike momenta. There are no such problems in analytic QCD.

  12. Advanced structures technology applied to a supersonic cruise arrow-wing configuration

    NASA Technical Reports Server (NTRS)

    Sakata, I. F.; Davis, G. W.

    1976-01-01

    The application of advanced technology to a promising aerodynamic configuration was explored to investigate the improved payload range characteristics over the configuration postulated during the National SST Program. The results of an analytical study performed to determine the best structural approach for design of a Mach number 2.7 arrow-wing supersonic cruise aircraft are highlighted. The data conducted under the auspices of the Structures Directorate of the National Aeronautics and Space Administration, Langley Research Center, established firm technical bases from which further trend studies were conducted to quantitatively assess the benefits and feasibility of using advanced structures technology to arrive at a viable advanced supersonic cruise aircraft.

  13. Bim Automation: Advanced Modeling Generative Process for Complex Structures

    NASA Astrophysics Data System (ADS)

    Banfi, F.; Fai, S.; Brumana, R.

    2017-08-01

    The new paradigm of the complexity of modern and historic structures, which are characterised by complex forms, morphological and typological variables, is one of the greatest challenges for building information modelling (BIM). Generation of complex parametric models needs new scientific knowledge concerning new digital technologies. These elements are helpful to store a vast quantity of information during the life cycle of buildings (LCB). The latest developments of parametric applications do not provide advanced tools, resulting in time-consuming work for the generation of models. This paper presents a method capable of processing and creating complex parametric Building Information Models (BIM) with Non-Uniform to NURBS) with multiple levels of details (Mixed and ReverseLoD) based on accurate 3D photogrammetric and laser scanning surveys. Complex 3D elements are converted into parametric BIM software and finite element applications (BIM to FEA) using specific exchange formats and new modelling tools. The proposed approach has been applied to different case studies: the BIM of modern structure for the courtyard of West Block on Parliament Hill in Ottawa (Ontario) and the BIM of Masegra Castel in Sondrio (Italy), encouraging the dissemination and interaction of scientific results without losing information during the generative process.

  14. Advanced model for fast assessment of piezoelectric micro energy harvesters

    NASA Astrophysics Data System (ADS)

    Ardito, Raffaele; Corigliano, Alberto; Gafforelli, Giacomo; Valzasina, Carlo; Procopio, Francesco; Zafalon, Roberto

    2016-04-01

    The purpose of this work is to present recent advances in modelling and design of piezoelectric energy harvesters, in the framework of Micro-Electro-Mechanical Systems (MEMS). More specifically, the case of inertial energy harvesting is considered, in the sense that the kinetic energy due to environmental vibration is transformed into electrical energy by means of piezoelectric transduction. The execution of numerical analyses is greatly important in order to predict the actual behaviour of MEMS devices and to carry out the optimization process. In the common practice, the results are obtained by means of burdensome 3D Finite Element Analyses (FEA). The case of beams could be treated by applying 1D models, which can enormously reduce the computational burden with obvious benefits in the case of repeated analyses. Unfortunately, the presence of piezoelectric coupling may entail some serious issues in view of its intrinsically three-dimensional behaviour. In this paper, a refined, yet simple, model is proposed with the objective of retaining the Euler-Bernoulli beam model, with the inclusion of effects connected to the actual three-dimensional shape of the device. The proposed model is adopted to evaluate the performances of realistic harvesters, both in the case of harmonic excitation and for impulsive loads.

  15. Fractional Calculus Model of Electrical Impedance Applied to Human Skin

    PubMed Central

    Vosika, Zoran B.; Lazovic, Goran M.; Misevic, Gradimir N.; Simic-Krstic, Jovana B.

    2013-01-01

    Fractional calculus is a mathematical approach dealing with derivatives and integrals of arbitrary and complex orders. Therefore, it adds a new dimension to understand and describe basic nature and behavior of complex systems in an improved way. Here we use the fractional calculus for modeling electrical properties of biological systems. We derived a new class of generalized models for electrical impedance and applied them to human skin by experimental data fitting. The primary model introduces new generalizations of: 1) Weyl fractional derivative operator, 2) Cole equation, and 3) Constant Phase Element (CPE). These generalizations were described by the novel equation which presented parameter related to remnant memory and corrected four essential parameters We further generalized single generalized element by introducing specific partial sum of Maclaurin series determined by parameters We defined individual primary model elements and their serial combination models by the appropriate equations and electrical schemes. Cole equation is a special case of our generalized class of models for Previous bioimpedance data analyses of living systems using basic Cole and serial Cole models show significant imprecisions. Our new class of models considerably improves the quality of fitting, evaluated by mean square errors, for bioimpedance data obtained from human skin. Our models with new parameters presented in specific partial sum of Maclaurin series also extend representation, understanding and description of complex systems electrical properties in terms of remnant memory effects. PMID:23577065

  16. Fractional calculus model of electrical impedance applied to human skin.

    PubMed

    Vosika, Zoran B; Lazovic, Goran M; Misevic, Gradimir N; Simic-Krstic, Jovana B

    2013-01-01

    Fractional calculus is a mathematical approach dealing with derivatives and integrals of arbitrary and complex orders. Therefore, it adds a new dimension to understand and describe basic nature and behavior of complex systems in an improved way. Here we use the fractional calculus for modeling electrical properties of biological systems. We derived a new class of generalized models for electrical impedance and applied them to human skin by experimental data fitting. The primary model introduces new generalizations of: 1) Weyl fractional derivative operator, 2) Cole equation, and 3) Constant Phase Element (CPE). These generalizations were described by the novel equation which presented parameter [Formula: see text] related to remnant memory and corrected four essential parameters [Formula: see text] We further generalized single generalized element by introducing specific partial sum of Maclaurin series determined by parameters [Formula: see text] We defined individual primary model elements and their serial combination models by the appropriate equations and electrical schemes. Cole equation is a special case of our generalized class of models for[Formula: see text] Previous bioimpedance data analyses of living systems using basic Cole and serial Cole models show significant imprecisions. Our new class of models considerably improves the quality of fitting, evaluated by mean square errors, for bioimpedance data obtained from human skin. Our models with new parameters presented in specific partial sum of Maclaurin series also extend representation, understanding and description of complex systems electrical properties in terms of remnant memory effects.

  17. A situation awareness model applied to multiple domains

    NASA Astrophysics Data System (ADS)

    Salerno, John J.; Hinman, Michael L.; Boulware, Douglas M.

    2005-03-01

    Full Spectrum Dominance, or as defined by Joint Vision 2020, the ability to be persuasive in peace, decisive in war and preeminent in any form of conflict, cannot be accomplished without the ability to know what the adversary is currently doing as well as the capacity to correctly anticipate the adversary's future actions. A key component in the ability to predict the adversary's intention is Situation Awareness (SA). In this paper we provide a discussion of an SA model, examine a specific instantiation of the model and demonstrate how it has been applied to two specific domains: Global Monitoring and Cyber Awareness. We conclude this paper with a discussion on future work.

  18. Advancing swine models for human health and diseases.

    PubMed

    Walters, Eric M; Prather, Randall S

    2013-01-01

    Swine models are relatively new kids on the block for modeling human health and diseases when compared to rodents and dogs. Because of the similarity to humans in size, physiology, and genetics, the pig has made significant strides in advancing the understanding of the human condition, and is thus an excellent choice for an animal model. Recent technological advances to genetic engineering of the swine genome enhance the utility of swine as models of human genetic diseases.

  19. GENERIC MODEL FOR MAGNETIC EXPLOSIONS APPLIED TO SOLAR FLARES

    SciTech Connect

    Melrose, D. B.

    2012-04-10

    An accepted model for magnetospheric substorms is proposed as the basis for a generic model for magnetic explosions and is applied to solar flares. The model involves widely separated energy-release and particle-acceleration regions, with energy transported Alfvenically between them. On a global scale, these regions are coupled by a large-scale current that is set up during the explosion by redirection of pre-existing current associated with the stored magnetic energy. The explosion-related current is driven by an electromotive force (EMF) due to the changing magnetic flux enclosed by this current. The current path and the EMF are identified for an idealized quadrupolar model for a flare.

  20. 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).

  1. Applying New Laser Interaction Models to the ORION Problem

    SciTech Connect

    Phipps, Claude; Sinko, John

    2010-10-08

    Previously, Phipps, et al. developed a model that permitted laser ablation impulse predictions within a factor of two over an extremely broad range of pulse durations and wavelengths in the plasma regime. This model lacked the ability to predict the intensity for optimum impulse generation. For the lower-intensity vapor regime, below the plasma transition, Sinko developed a useful, fluence-dependent model which predicts impulse delivered for pulsed lasers on polymers at a specific wavelength. Phipps subsequently developed an alternate model which treats elemental solids in the vapor regime, that only requires knowledge of basic material parameters and vapor pressure vs. temperature data. These data, except for optical absorptivity, are wavelength-independent. A simple technique combines either vapor model with the plasma model to form a complete model that moves smoothly through the vapor to plasma transition. In this paper, we apply these models to show the optimum momentum coupling fluence on target, at the transition from the vapor to the plasma regimes, for aluminum (a typical debris material) and polyoxymethylene (representing polymeric debris). The application of this work is the ORION laser space debris mitigation concept. This is an improvement over previous work, in which this optimum was only estimated from the plasma ignition threshold. We present calculations showing how impulse delivered to debris targets in the ORION concept varies with pulse duration, at an optimum fluence determined by nonlinear optical effects in the Earth's atmosphere.

  2. Apply a hydrological model to estimate local temperature trends

    NASA Astrophysics Data System (ADS)

    Igarashi, Masao; Shinozawa, Tatsuya

    2014-03-01

    Continuous times series {f(x)} such as a depth of water is written f(x) = T(x)+P(x)+S(x)+C(x) in hydrological science where T(x),P(x),S(x) and C(x) are called the trend, periodic, stochastic and catastrophic components respectively. We simplify this model and apply it to the local temperature data such as given E. Halley (1693), the UK (1853-2010), Germany (1880-2010), Japan (1876-2010). We also apply the model to CO2 data. The model coefficients are evaluated by a symbolic computation by using a standard personal computer. The accuracy of obtained nonlinear curve is evaluated by the arithmetic mean of relative errors between the data and estimations. E. Halley estimated the temperature of Gresham College from 11/1692 to 11/1693. The simplified model shows that the temperature at the time rather cold compared with the recent of London. The UK and Germany data sets show that the maximum and minimum temperatures increased slowly from the 1890s to 1940s, increased rapidly from the 1940s to 1980s and have been decreasing since the 1980s with the exception of a few local stations. The trend of Japan is similar to these results.

  3. Measurement and modeling of advanced coal conversion processes

    SciTech Connect

    Solomon, P.R.; Serio, M.A.; Hamblen, D.G. ); Smoot, L.D.; Brewster, B.S. )

    1992-01-01

    The objectives of this proposed study are to establish the mechanisms and rates of basic steps in coal conversion processes, to integrate and incorporate this information into comprehensive computer models for coal conversion processes, to evaluate these models and to apply them to gasification, mild gasification and combustion in heat engines. This report describes progress during twenty second quarter of the program. Specifically, the paper discusses progress in three task areas: (1) Submodel development and evaluation: coal to char chemistry submodel; fundamental high-pressure reaction rate data; secondary reaction of pyrolysis product and burnout submodels; ash physics and chemistry submodel; large particle submodels; large char particle oxidation at high pressures; and SO[sub x]-NO[sub x] submodel development and evaluation; (2) Comprehensive model development and evaluation: integration of advanced submodels into entrained-flow code, with evaluation and documentation; comprehensive fixed-bed modeling review, development evaluation and implementation; and generalized fuels feedstock submodel; and (3) Application of integrated codes: application of generalized pulverized coal comprehensive code and application of fixed-bed code.

  4. The Advancement Value Chain: An Exploratory Model

    ERIC Educational Resources Information Center

    Leonard, Edward F., III

    2005-01-01

    Since the introduction of the value chain concept in 1985, several varying, yet virtually similar, value chains have been developed for the business enterprise. Shifting to higher education, can a value chain be found that links together the various activities of advancement so that an institution's leaders can actually look at the philanthropic…

  5. Advanced Placement: Model Policy Components. Policy Analysis

    ERIC Educational Resources Information Center

    Zinth, Jennifer

    2016-01-01

    Advanced Placement (AP), launched in 1955 by the College Board as a program to offer gifted high school students the opportunity to complete entry-level college coursework, has since expanded to encourage a broader array of students to tackle challenging content. This Education Commission of the State's Policy Analysis identifies key components of…

  6. Predicting Career Advancement with Structural Equation Modelling

    ERIC Educational Resources Information Center

    Heimler, Ronald; Rosenberg, Stuart; Morote, Elsa-Sofia

    2012-01-01

    Purpose: The purpose of this paper is to use the authors' prior findings concerning basic employability skills in order to determine which skills best predict career advancement potential. Design/methodology/approach: Utilizing survey responses of human resource managers, the employability skills showing the largest relationships to career…

  7. Predicting Career Advancement with Structural Equation Modelling

    ERIC Educational Resources Information Center

    Heimler, Ronald; Rosenberg, Stuart; Morote, Elsa-Sofia

    2012-01-01

    Purpose: The purpose of this paper is to use the authors' prior findings concerning basic employability skills in order to determine which skills best predict career advancement potential. Design/methodology/approach: Utilizing survey responses of human resource managers, the employability skills showing the largest relationships to career…

  8. Remote sensing applied to numerical modelling. [water resources pollution

    NASA Technical Reports Server (NTRS)

    Sengupta, S.; Lee, S. S.; Veziroglu, T. N.; Bland, R.

    1975-01-01

    Progress and remaining difficulties in the construction of predictive mathematical models of large bodies of water as ecosystems are reviewed. Surface temperature is at present the only variable than can be measured accurately and reliably by remote sensing techniques, but satellite infrared data are of sufficient resolution for macro-scale modeling of oceans and large lakes, and airborne radiometers are useful in meso-scale analysis (of lakes, bays, and thermal plumes). Finite-element and finite-difference techniques applied to the solution of relevant coupled time-dependent nonlinear partial differential equations are compared, and the specific problem of the Biscayne Bay and environs ecosystem is tackled in a finite-differences treatment using the rigid-lid model and a rigid-line grid system.

  9. Remote sensing applied to numerical modelling. [water resources pollution

    NASA Technical Reports Server (NTRS)

    Sengupta, S.; Lee, S. S.; Veziroglu, T. N.; Bland, R.

    1975-01-01

    Progress and remaining difficulties in the construction of predictive mathematical models of large bodies of water as ecosystems are reviewed. Surface temperature is at present the only variable than can be measured accurately and reliably by remote sensing techniques, but satellite infrared data are of sufficient resolution for macro-scale modeling of oceans and large lakes, and airborne radiometers are useful in meso-scale analysis (of lakes, bays, and thermal plumes). Finite-element and finite-difference techniques applied to the solution of relevant coupled time-dependent nonlinear partial differential equations are compared, and the specific problem of the Biscayne Bay and environs ecosystem is tackled in a finite-differences treatment using the rigid-lid model and a rigid-line grid system.

  10. Challenges in Modeling the Fate of Nitrogen Applied to Forests

    NASA Astrophysics Data System (ADS)

    Amatya, Devendra; Trettin, C.; Vance, Eric; Nettles, Jami; Skaggs, Wayne

    2008-06-01

    Development of a Comprehensive Forest Nutrient Cycle and Export Modeling Package; Cordesville, South Carolina, 6-7 March 2008; Nitrogen (N) fertilizer is commonly applied to increase productivity of forest plantations, and the extent and intensity of forest fertilizer use could increase in the future as a way of enhancing forest productivity to meet demands for both traditional products and emerging markets for energy and biomaterials. While much of the applied N remains in the soil-plant system, there are concerns about leaching losses and effects on surface water quality. However, understanding the fate of fertilizer N and its potential environmental impacts is particularly complex due to a wide range of abiotic and biotic factors affecting its forms and movement.

  11. The promises and pitfalls of applying computational models to neurological and psychiatric disorders.

    PubMed

    Teufel, Christoph; Fletcher, Paul C

    2016-10-01

    Computational models have become an integral part of basic neuroscience and have facilitated some of the major advances in the field. More recently, such models have also been applied to the understanding of disruptions in brain function. In this review, using examples and a simple analogy, we discuss the potential for computational models to inform our understanding of brain function and dysfunction. We argue that they may provide, in unprecedented detail, an understanding of the neurobiological and mental basis of brain disorders and that such insights will be key to progress in diagnosis and treatment. However, there are also potential problems attending this approach. We highlight these and identify simple principles that should always govern the use of computational models in clinical neuroscience, noting especially the importance of a clear specification of a model's purpose and of the mapping between mathematical concepts and reality.

  12. A Log Logistic Survival Model Applied to Hypobaric Decompression Sickness

    NASA Technical Reports Server (NTRS)

    Conkin, Johnny

    2001-01-01

    Decompression sickness (DCS) is a complex, multivariable problem. A mathematical description or model of the likelihood of DCS requires a large amount of quality research data, ideas on how to define a decompression dose using physical and physiological variables, and an appropriate analytical approach. It also requires a high-performance computer with specialized software. I have used published DCS data to develop my decompression doses, which are variants of equilibrium expressions for evolved gas plus other explanatory variables. My analytical approach is survival analysis, where the time of DCS occurrence is modeled. My conclusions can be applied to simple hypobaric decompressions - ascents lasting from 5 to 30 minutes - and, after minutes to hours, to denitrogenation (prebreathing). They are also applicable to long or short exposures, and can be used whether the sufferer of DCS is at rest or exercising at altitude. Ultimately I would like my models to be applied to astronauts to reduce the risk of DCS during spacewalks, as well as to future spaceflight crews on the Moon and Mars.

  13. Inverse geothermal modelling applied to Danish sedimentary basins

    NASA Astrophysics Data System (ADS)

    Poulsen, Søren E.; Balling, Niels; Bording, Thue S.; Mathiesen, Anders; Nielsen, Søren B.

    2017-10-01

    This paper presents a numerical procedure for predicting subsurface temperatures and heat-flow distribution in 3-D using inverse calibration methodology. The procedure is based on a modified version of the groundwater code MODFLOW by taking advantage of the mathematical similarity between confined groundwater flow (Darcy's law) and heat conduction (Fourier's law). Thermal conductivity, heat production and exponential porosity-depth relations are specified separately for the individual geological units of the model domain. The steady-state temperature model includes a model-based transient correction for the long-term palaeoclimatic thermal disturbance of the subsurface temperature regime. Variable model parameters are estimated by inversion of measured borehole temperatures with uncertainties reflecting their quality. The procedure facilitates uncertainty estimation for temperature predictions. The modelling procedure is applied to Danish onshore areas containing deep sedimentary basins. A 3-D voxel-based model, with 14 lithological units from surface to 5000 m depth, was built from digital geological maps derived from combined analyses of reflection seismic lines and borehole information. Matrix thermal conductivity of model lithologies was estimated by inversion of all available deep borehole temperature data and applied together with prescribed background heat flow to derive the 3-D subsurface temperature distribution. Modelled temperatures are found to agree very well with observations. The numerical model was utilized for predicting and contouring temperatures at 2000 and 3000 m depths and for two main geothermal reservoir units, the Gassum (Lower Jurassic-Upper Triassic) and Bunter/Skagerrak (Triassic) reservoirs, both currently utilized for geothermal energy production. Temperature gradients to depths of 2000-3000 m are generally around 25-30 °C km-1, locally up to about 35 °C km-1. Large regions have geothermal reservoirs with characteristic temperatures

  14. Cumulative Damage Model for Advanced Composite Materials.

    DTIC Science & Technology

    1982-09-01

    conditions of static loads; various theories have been advanced to predict the onset and progress of these individual damage events. • The approach taken in...composite laminates, one common approach is the well-known "first ply failure" theory (see e.g. Tsai and Hahn [l]). The basic assumption in the theory ...edge interlaminar stresses provides a physical x tai,-ntion of the edge delamination phenomenon; a suitable theory defining t he conditions for its

  15. Advanced Interconnect and Device-Field Modeling

    DTIC Science & Technology

    2007-01-15

    Essaaidi NATO Advanced Research Workshop : Bianisotropics 2002, 99th Conference on Electromagnetics of Complex Media 8-11May, 2002, Marrakech , Morocco...Bianisotropics 2002, 99th Conference on Electromagnetics of Complex Media 8-11May, 2002, Marrakech , Morocco. Study of Substrates Bi-anisotropy Effects on...Conference on Electromagnetics of Complex Media 8-11May, 2002, Marrakech , Morocco. Dielectric Substrates Anisotropic Effects on The Characteristics of

  16. PARTNERING WITH DOE TO APPLY ADVANCED BIOLOGICAL, ENVIRONMENTAL, AND COMPUTATIONAL SCIENCE TO ENVIRONMENTAL ISSUES

    EPA Science Inventory

    On February 18, 2004, the U.S. Environmental Protection Agency and Department of Energy signed a Memorandum of Understanding to expand the research collaboration of both agencies to advance biological, environmental, and computational sciences for protecting human health and the ...

  17. PARTNERING WITH DOE TO APPLY ADVANCED BIOLOGICAL, ENVIRONMENTAL, AND COMPUTATIONAL SCIENCE TO ENVIRONMENTAL ISSUES

    EPA Science Inventory

    On February 18, 2004, the U.S. Environmental Protection Agency and Department of Energy signed a Memorandum of Understanding to expand the research collaboration of both agencies to advance biological, environmental, and computational sciences for protecting human health and the ...

  18. 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.

  19. A GIS modeling method applied to predicting forest songbird habitat

    USGS Publications Warehouse

    Dettmers, Randy; Bart, Jonathan

    1999-01-01

    We have developed an approach for using a??presencea?? data to construct habitat models. Presence data are those that indicate locations where the target organism is observed to occur, but that cannot be used to define locations where the organism does not occur. Surveys of highly mobile vertebrates often yield these kinds of data. Models developed through our approach yield predictions of the amount and the spatial distribution of good-quality habitat for the target species. This approach was developed primarily for use in a GIS context; thus, the models are spatially explicit and have the potential to be applied over large areas. Our method consists of two primary steps. In the first step, we identify an optimal range of values for each habitat variable to be used as a predictor in the model. To find these ranges, we employ the concept of maximizing the difference between cumulative distribution functions of (1) the values of a habitat variable at the observed presence locations of the target organism, and (2) the values of that habitat variable for all locations across a study area. In the second step, multivariate models of good habitat are constructed by combining these ranges of values, using the Boolean operators a??anda?? and a??or.a?? We use an approach similar to forward stepwise regression to select the best overall model. We demonstrate the use of this method by developing species-specific habitat models for nine forest-breeding songbirds (e.g., Cerulean Warbler, Scarlet Tanager, Wood Thrush) studied in southern Ohio. These models are based on speciesa?? microhabitat preferences for moisture and vegetation characteristics that can be predicted primarily through the use of abiotic variables. We use slope, land surface morphology, land surface curvature, water flow accumulation downhill, and an integrated moisture index, in conjunction with a land-cover classification that identifies forest/nonforest, to develop these models. The performance of these

  20. Evidence synthesis through a degradation model applied to myocardial infarction

    PubMed Central

    Commenges, Daniel; Hejblum, Boris P.

    2013-01-01

    We propose an evidence synthesis approach through a degradation model to estimate causal influences of physiological factors on myocardial infarction (MI) and coronary heart disease (CHD). For instance several studies give incidences of MI and CHD for different age strata, other studies give relative or absolute risks for strata of main risk factors of MI or CHD. Evidence synthesis of several studies allows incorporating these disparate pieces of information into a single model. For doing this we need to develop a sufficiently general dynamical model; we also need to estimate the distribution of explanatory factors in the population. We develop a degradation model for both MI and CHD using a Brownian motion with drift, and the drift is modeled as a function of indicators of obesity, lipid profile, inflammation and blood pressure. Conditionally on these factors the times to MI or CHD have inverse Gaussian ( ) distributions. The results we want to fit are generally not conditional on all the factors and thus we need marginal distributions of the time of occurrence of MI and CHD; this leads us to manipulate the inverse Gaussian normal distribution ( ) (an whose drift parameter has a normal distribution). Another possible model arises if a factor modifies the threshold. This led us to define an extension of obtained when both drift and threshold parameters have normal distributions. We applied the model to results published in five important studies of MI and CHD and their risk factors. The fit of the model using the evidence synthesis approach was satisfactory and the effects of the four risk factors were highly significant. PMID:22918702

  1. Synthetic modelling of acoustical propagation applied to seismic oceanography experiments

    NASA Astrophysics Data System (ADS)

    Kormann, Jean; Cobo, Pedro; Biescas, Berta; Sallarés, Valentí; Papenberg, Cord; Recuero, Manuel; Carbonell, Ramón

    2010-03-01

    Recent work shows that multichannel seismic (MCS) systems provide detailed information on the oceans' finestructure. The aim of this paper is to analyze if high order numerical algorithms are suitable to accurately model the extremely weak wavefield scattered by the oceans' finestructures. For this purpose, we generate synthetic shot records along a coincident seismic and oceanographic profile acquired across a Mediterranean salt lens in the Gulf of Cadiz. We apply a 2D finite-difference time-domain propagation model, together with second-order Complex Frequency Shifted Perfectly Matched Layers at the numerical boundaries, using as reference a realistic sound speed map with the lateral resolution of the seismic data. We show that our numerical propagator creates an acoustical image of the ocean finestructures including the salt lens that reproduces with outstanding detail the real acquired one.

  2. A comparison of atmospheric loading models applied to SLR data

    NASA Astrophysics Data System (ADS)

    Koenig, Rolf; Dill, Robert; Raimondo, Jean-Claude; Vei, Margarita

    2016-04-01

    We compute displacements of global SLR station coordinates by atmospheric loading based on surface pressure data from European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-interim data. Inhouse we generate two branches: firstly straightforward following Farrel's theory but using updated load Love numbers, secondly from utilizing localized Green's functions instead of global ones. Externally provided displacements are available f.i. from the International Mass Loading Service (IMLS) based on different input data and modeling. We compare these displacements and apply them to Satellite Laser Ranging (SLR) data processing of a recent six years period of the LAGEOS, LARES, AJISAI, STARLETTE and STELLA geodetic missions. We assess the impact of the loading models on precise orbit determination and Earth parameters of interest.

  3. Advancing complementary and alternative medicine through social network analysis and agent-based modeling.

    PubMed

    Frantz, Terrill L

    2012-01-01

    This paper introduces the contemporary perspectives and techniques of social network analysis (SNA) and agent-based modeling (ABM) and advocates applying them to advance various aspects of complementary and alternative medicine (CAM). SNA and ABM are invaluable methods for representing, analyzing and projecting complex, relational, social phenomena; they provide both an insightful vantage point and a set of analytic tools that can be useful in a wide range of contexts. Applying these methods in the CAM context can aid the ongoing advances in the CAM field, in both its scientific aspects and in developing broader acceptance in associated stakeholder communities.

  4. Enabling Advanced Modeling and Simulations for Fuel-Flexible Combustors

    SciTech Connect

    Pitsch, Heinz

    2010-05-31

    The overall goal of the present project is to enable advanced modeling and simulations for the design and optimization of fuel-flexible turbine combustors. For this purpose we use a high fidelity, extensively-tested large-eddy simulation (LES) code and state-of-the-art models for premixed/partially-premixed turbulent combustion developed in the PI's group. In the frame of the present project, these techniques are applied, assessed, and improved for hydrogen enriched premixed and partially premixed gas-turbine combustion. Our innovative approaches include a completely consistent description of flame propagation; a coupled progress variable/level set method to resolve the detailed flame structure, and incorporation of thermal-diffusion (non-unity Lewis number) effects. In addition, we have developed a general flamelet-type transformation holding in the limits of both non-premixed and premixed burning. As a result, a model for partially premixed combustion has been derived. The coupled progress variable/level method and the general flamelet transformation were validated by LES of a lean-premixed low-swirl burner that has been studied experimentally at Lawrence Berkeley National Laboratory. The model is extended to include the non-unity Lewis number effects, which play a critical role in fuel-flexible combustor with high hydrogen content fuel. More specifically, a two-scalar model for lean hydrogen and hydrogen-enriched combustion is developed and validated against experimental and direct numerical simulation (DNS) data. Results are presented to emphasize the importance of non-unity Lewis number effects in the lean-premixed low-swirl burner of interest in this project. The proposed model gives improved results, which shows that the inclusion of the non-unity Lewis number effects is essential for accurate prediction of the lean-premixed low-swirl flame.

  5. Enabling Advanced Modeling and Simulations for Fuel-Flexible Combustors

    SciTech Connect

    Heinz Pitsch

    2010-05-31

    The overall goal of the present project is to enable advanced modeling and simulations for the design and optimization of fuel-flexible turbine combustors. For this purpose we use a high-fidelity, extensively-tested large-eddy simulation (LES) code and state-of-the-art models for premixed/partially-premixed turbulent combustion developed in the PI's group. In the frame of the present project, these techniques are applied, assessed, and improved for hydrogen enriched premixed and partially premixed gas-turbine combustion. Our innovative approaches include a completely consistent description of flame propagation, a coupled progress variable/level set method to resolve the detailed flame structure, and incorporation of thermal-diffusion (non-unity Lewis number) effects. In addition, we have developed a general flamelet-type transformation holding in the limits of both non-premixed and premixed burning. As a result, a model for partially premixed combustion has been derived. The coupled progress variable/level method and the general flamelet tranformation were validated by LES of a lean-premixed low-swirl burner that has been studied experimentally at Lawrence Berkeley National Laboratory. The model is extended to include the non-unity Lewis number effects, which play a critical role in fuel-flexible combustor with high hydrogen content fuel. More specifically, a two-scalar model for lean hydrogen and hydrogen-enriched combustion is developed and validated against experimental and direct numerical simulation (DNS) data. Results are presented to emphasize the importance of non-unity Lewis number effects in the lean-premixed low-swirl burner of interest in this project. The proposed model gives improved results, which shows that the inclusion of the non-unity Lewis number effects is essential for accurate prediction of the lean-premixed low-swirl flame.

  6. Applying the luminosity function statistics in the fireshell model

    NASA Astrophysics Data System (ADS)

    Rangel Lemos, L. J.; Bianco, C. L.; Ruffini, R.

    2015-12-01

    The luminosity function (LF) statistics applied to the data of BATSE, GBM/Fermi and BAT/Swift is the theme approached in this work. The LF is a strong statistical tool to extract useful information from astrophysical samples, and the key point of this statistical analysis is in the detector sensitivity, where we have performed careful analysis. We applied the tool of the LF statistics to three GRB classes predicted by the Fireshell model. We produced, by LF statistics, predicted distributions of: peak ux N(Fph pk), redshift N(z) and peak luminosity N(Lpk) for the three GRB classes predicted by Fireshell model; we also used three GRB rates. We looked for differences among the distributions, and in fact we found. We performed a comparison between the distributions predicted and observed (with and without redshifts), where we had to build a list with 217 GRBs with known redshifts. Our goal is transform the GRBs in a standard candle, where a alternative is find a correlation between the isotropic luminosity and the Band peak spectral energy (Liso - Epk).

  7. Transtheoretical model of health behavior change applied to voice therapy.

    PubMed

    van Leer, Eva; Hapner, Edie R; Connor, Nadine P

    2008-11-01

    Studies of patient adherence to health behavior programs, such as physical exercise, smoking cessation, and diet, have resulted in the formulation and validation of the Transtheoretical Model (TTM) of behavior change. Although widely accepted as a guide for the development of health behavior interventions, this model has not been applied to vocal rehabilitation. Because resolution of vocal difficulties frequently depends on a patient's ability to make changes in vocal and health behaviors, the TTM may be a useful way to conceptualize voice behavior change processes, including the patient's readiness for change. The purpose of this paper is to apply the TTM to the voice therapy process to: (1) provide an organizing framework for understanding of behavior change in voice therapy, (2) explain how treatment adherence problems can arise, and (3) provide broad strategies to improve treatment adherence. Given the significant role of treatment adherence in treatment outcome, considering readiness for behavior change should be taken into account when planning treatment. Principles of health behavior change can aid speech pathologists in such understanding and estimating readiness for voice therapy.

  8. The promises and pitfalls of applying computational models to neurological and psychiatric disorders

    PubMed Central

    Teufel, Christoph

    2016-01-01

    Computational models have become an integral part of basic neuroscience and have facilitated some of the major advances in the field. More recently, such models have also been applied to the understanding of disruptions in brain function. In this review, using examples and a simple analogy, we discuss the potential for computational models to inform our understanding of brain function and dysfunction. We argue that they may provide, in unprecedented detail, an understanding of the neurobiological and mental basis of brain disorders and that such insights will be key to progress in diagnosis and treatment. However, there are also potential problems attending this approach. We highlight these and identify simple principles that should always govern the use of computational models in clinical neuroscience, noting especially the importance of a clear specification of a model’s purpose and of the mapping between mathematical concepts and reality. PMID:27543973

  9. The lag RST turbulence model applied to vortical flows

    NASA Astrophysics Data System (ADS)

    Churchfield, Matthew John

    The subject of this work is the application of Olsen and Coakley's Reynolds stress relaxation turbulence model, which they call the lag Reynold stress transport (RST) model, to wingtip vortex flows. The lag RST model is meant for general non-equilibrium turbulent flows, and has not been applied to vortical flows before this work. Such a model relaxes the Reynolds stresses toward their equilibrium value, determined by the Boussinesq approximation, at a rate depending on a model constant, alpha0, multiplied by the specific dissipation rate of the turbulence, o. The alpha 0 constant can be adjusted to vary the rate at which the Reynolds stress tensor relaxes toward its equilibrium value. It performs this relaxation by solving for the equilibrium Reynolds stresses using Wilcox's k-o model, but then uses a relaxation equation to solve for the actual Reynolds stress tensor. The lag RST turbulence model allows the principal axes of the Reynolds stress tensor to be misaligned with those of the mean strain rate tensor, something linear eddy viscosity models cannot do, but something that occurs in actual vortical flows. The lag RST model is used with the Reynolds-averaged Navier-Stokes (RANS) equations to compute a one-dimensional, time-varying, line vortex with axial flow, called the q-vortex. Direct numerical simulation (DNS) data is available for comparison. Also, a modified version of the OVERFLOW code is used to solve the RANS and lag RST model equations in a three-dimensional wingtip vortex flow, for which there is experimental data. This work shows that computations performed with the lag RST model have a mean flow in much better agreement with the DNS or experimental data than those performed with the k-o model, the lag RST model's base. In fact, the lag RST model performs equally or better in this these flows than the well performing Spalart-Allmaras model with a correction for streamline curvature and rotation. As the lag parameter alpha0 is decreased, the amount

  10. A bidirectional coupling procedure applied to multiscale respiratory modeling

    NASA Astrophysics Data System (ADS)

    Kuprat, A. P.; Kabilan, S.; Carson, J. P.; Corley, R. A.; Einstein, D. R.

    2013-07-01

    pressure applied to the multiple sets of ODEs. In both the simplified geometry and in the imaging-based geometry, the performance of the method was comparable to that of monolithic schemes, in most cases requiring only a single CFD evaluation per time step. Thus, this new accelerator allows us to begin combining pulmonary CFD models with lower-dimensional models of pulmonary mechanics with little computational overhead. Moreover, because the CFD and lower-dimensional models are totally separate, this framework affords great flexibility in terms of the type and breadth of the adopted lower-dimensional model, allowing the biomedical researcher to appropriately focus on model design. Research funded by the National Heart and Blood Institute Award 1RO1HL073598.

  11. A Bidirectional Coupling Procedure Applied to Multiscale Respiratory Modeling.

    PubMed

    Kuprat, A P; Kabilan, S; Carson, J P; Corley, R A; Einstein, D R

    2013-07-01

    In this study, we present a novel multiscale computational framework for efficiently linking multiple lower-dimensional models describing the distal lung mechanics to imaging-based 3D computational fluid dynamics (CFD) models of the upper pulmonary airways in order to incorporate physiologically appropriate outlet boundary conditions. The framework is an extension of the Modified Newton's Method with nonlinear Krylov accelerator developed by Carlson and Miller [1, 2, 3]. Our extensions include the retention of subspace information over multiple timesteps, and a special correction at the end of a timestep that allows for corrections to be accepted with verified low residual with as little as a single residual evaluation per timestep on average. In the case of a single residual evaluation per timestep, the method has zero additional computational cost compared to uncoupled or unidirectionally coupled simulations. We expect these enhancements to be generally applicable to other multiscale coupling applications where timestepping occurs. In addition we have developed a "pressure-drop" residual which allows for stable coupling of flows between a 3D incompressible CFD application and another (lower-dimensional) fluid system. We expect this residual to also be useful for coupling non-respiratory incompressible fluid applications, such as multiscale simulations involving blood flow. The lower-dimensional models that are considered in this study are sets of simple ordinary differential equations (ODEs) representing the compliant mechanics of symmetric human pulmonary airway trees. To validate the method, we compare the predictions of hybrid CFD-ODE models against an ODE-only model of pulmonary airflow in an idealized geometry. Subsequently, we couple multiple sets of ODEs describing the distal lung to an imaging-based human lung geometry. Boundary conditions in these models consist of atmospheric pressure at the mouth and intrapleural pressure applied to the multiple sets

  12. A Bidirectional Coupling Procedure Applied to Multiscale Respiratory Modeling

    SciTech Connect

    Kuprat, Andrew P.; Kabilan, Senthil; Carson, James P.; Corley, Richard A.; Einstein, Daniel R.

    2013-07-01

    In this study, we present a novel multiscale computational framework for efficiently linking multiple lower-dimensional models describing the distal lung mechanics to imaging-based 3D computational fluid dynamics (CFD) models of the upper pulmonary airways in order to incorporate physiologically appropriate outlet boundary conditions. The framework is an extension of the Modified Newton’s Method with nonlinear Krylov accelerator developed by Carlson and Miller [1, 2, 3]. Our extensions include the retention of subspace information over multiple timesteps, and a special correction at the end of a timestep that allows for corrections to be accepted with verified low residual with as little as a single residual evaluation per timestep on average. In the case of a single residual evaluation per timestep, the method has zero additional computational cost compared to uncoupled or unidirectionally coupled simulations. We expect these enhancements to be generally applicable to other multiscale coupling applications where timestepping occurs. In addition we have developed a “pressure-drop” residual which allows for stable coupling of flows between a 3D incompressible CFD application and another (lower-dimensional) fluid system. We expect this residual to also be useful for coupling non-respiratory incompressible fluid applications, such as multiscale simulations involving blood flow. The lower-dimensional models that are considered in this study are sets of simple ordinary differential equations (ODEs) representing the compliant mechanics of symmetric human pulmonary airway trees. To validate the method, we compare the predictions of hybrid CFD-ODE models against an ODE-only model of pulmonary airflow in an idealized geometry. Subsequently, we couple multiple sets of ODEs describing the distal lung to an imaging-based human lung geometry. Boundary conditions in these models consist of atmospheric pressure at the mouth and intrapleural pressure applied to the multiple

  13. A bidirectional coupling procedure applied to multiscale respiratory modeling

    SciTech Connect

    Kuprat, A.P.; Kabilan, S.; Carson, J.P.; Corley, R.A.; Einstein, D.R.

    2013-07-01

    pressure applied to the multiple sets of ODEs. In both the simplified geometry and in the imaging-based geometry, the performance of the method was comparable to that of monolithic schemes, in most cases requiring only a single CFD evaluation per time step. Thus, this new accelerator allows us to begin combining pulmonary CFD models with lower-dimensional models of pulmonary mechanics with little computational overhead. Moreover, because the CFD and lower-dimensional models are totally separate, this framework affords great flexibility in terms of the type and breadth of the adopted lower-dimensional model, allowing the biomedical researcher to appropriately focus on model design. Research funded by the National Heart and Blood Institute Award 1RO1HL073598.

  14. Thermal Model Predictions of Advanced Stirling Radioisotope Generator Performance

    NASA Technical Reports Server (NTRS)

    Wang, Xiao-Yen J.; Fabanich, William Anthony; Schmitz, Paul C.

    2014-01-01

    This presentation describes the capabilities of three-dimensional thermal power model of advanced stirling radioisotope generator (ASRG). The performance of the ASRG is presented for different scenario, such as Venus flyby with or without the auxiliary cooling system.

  15. APPLYING A SPATIOTEMPORAL MODEL FOR LONGITUDINAL CARDIAC IMAGING DATA

    PubMed Central

    George, Brandon; Denney, Thomas; Gupta, Himanshu; Dell’Italia, Louis; Aban, Inmaculada

    2016-01-01

    Longitudinal imaging studies have both spatial and temporal correlation among the multiple outcome measurements from a subject. Statistical methods of analysis must properly account for this autocorrelation. In this work we discuss how a linear model with a separable parametric correlation structure could be used to analyze data from such a study. The goal of this paper is to provide an easily understood description of how such a model works and discuss how it can be applied to real data. Model assumptions are discussed and the process of selecting a working correlation structure is thoroughly discussed. The steps necessitating collaboration between statistical and scientific investigators have been highlighted, as have considerations for missing data or uneven follow-up. The results from a completed longitudinal cardiac imaging study were considered for illustration purposes. The data comes from a clinical trial for medical therapy for patients with mitral regurgitation, with repeated measurements taken at sixteen locations from the left ventricle to measure disease progression. The spatiotemporal correlation model was compared to previously used summary measures to demonstrate improved power as well as increased flexibility in the use of time- and space-varying predictors. PMID:27087884

  16. Chemical Kinetic Models for Advanced Engine Combustion

    SciTech Connect

    Pitz, William J.; Mehl, Marco; Westbrook, Charles K.

    2014-10-22

    The objectives for this project are as follows: Develop detailed chemical kinetic models for fuel components used in surrogate fuels for compression ignition (CI), homogeneous charge compression ignition (HCCI) and reactivity-controlled compression-ignition (RCCI) engines; and Combine component models into surrogate fuel models to represent real transportation fuels. Use them to model low-temperature combustion strategies in HCCI, RCCI, and CI engines that lead to low emissions and high efficiency.

  17. Recent advances in crop growth modeling

    USDA-ARS?s Scientific Manuscript database

    Crop simulation models and model-based decision support systems are increasingly used to assist agricultural research and development. The systems approach and modelling tools have been linked down to scales of functional genomics and up to regional scales of natural resource management. Although cr...

  18. Non-homogeneous biofilm modeling applied to bioleaching processes.

    PubMed

    Olivera-Nappa, Alvaro; Picioreanu, Cristian; Asenjo, Juan A

    2010-07-01

    A two-dimensional non-homogeneous biofilm model is proposed for the first time to study chemical and biochemical reactions at the microorganism scale applied to biological metal leaching from mineral ores. The spatial and temporal relation between these reactions, microorganism growth and the morphological changes of the biofilm caused by solid inorganic precipitate formation were studied using this model. The model considers diffusion limitations due to accumulation of inorganic particles over the mineral substratum, and allows the study of the effect of discrete phases on chemical and microbiological mineral solubilization. The particle-based modeling strategy allowed representation of contact reactions between the microorganisms and the insoluble precipitates, such as those required for sulfur attack and solubilization. Time-dependent simulations of chemical chalcopyrite leaching showed that chalcopyrite passivation occurs only when an impervious solid layer is formed on the mineral surface. This mineral layer hinders the diffusion of one kinetically determinant mineral-attacking chemical species through a nearly irreversible chemical mechanism. Simulations with iron and sulfur oxidizing microorganisms revealed that chemolithoautotrophic biofilms are able to delay passivation onset by formation of corrosion pits and increase of the solid layer porosity through sulfur dissolution. The model results also show that the observed flat morphology of bioleaching biofilms is favored preferentially at low iron concentrations due to preferential growth at the biofilm edge on the surface of sulfur-forming minerals. Flat biofilms can also be advantageous for chalcopyrite bioleaching because they tend to favor sulfur dissolution over iron oxidation. The adopted modeling strategy is of great interest for the numerical representation of heterogeneous biofilm systems including abiotic solid particles.

  19. Advances in modelling of condensation phenomena

    SciTech Connect

    Liu, W.S.; Zaltsgendler, E.; Hanna, B.

    1997-07-01

    The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUF are described.

  20. Applying modern measurements of Pleistocene loads to model lithospheric rheology

    NASA Astrophysics Data System (ADS)

    Beard, E. P.; Hoggan, J. R.; Lowry, A. R.

    2011-12-01

    The remnant shorelines of Pleistocene Lake Bonneville provide a unique opportunity for building a dataset from which to infer rheological properties of the lower crust and upper mantle. Multiple lakeshores developed over a period of around 30 kyr which record the lithosphere's isostatic response to a well-constrained load history. Bills et al. (1994) utilized a shoreline elevation dataset compiled by Currey (1982) in an attempt to model linear (Maxwell) viscosity as a function of depth beneath the basin. They estimated an effective elastic thickness (Te) for the basin of 20-25 km which differs significantly from the 5-15 km estimates derived from models of loading on geologic timescales (e.g., Lowry and Pérez-Gussinyé, 2011). We propose that the discrepancy in Te modeled by these two approaches may be resolved with dynamical modeling of a common rheology, using a more complete shoreline elevation dataset applied to a spherical Earth model. Where Currey's (1982) dataset was compiled largely from observations of depositional shoreline features, we are developing an algorithm for estimating elevation variations in erosional shorelines based on cross-correlation and stacking techniques similar to those used to automate picking of seismic phase arrival times. Application of this method to digital elevation models (DEMs) will increase the size and accuracy of the shoreline elevation dataset, enabling more robust modeling of the rheological properties driving isostatic response to unloading of Lake Bonneville. Our plan is to model these data and invert for a relatively small number of parameters describing depth- and temperature-dependent power-law rheology of the lower crust and upper mantle. These same parameters also will be used to model topographic and Moho response to estimates of regional mass variation on the longer loading timescales to test for inconsistencies. Bills, B.G., D.R. Currey, and G.A. Marshall, 1994, Viscosity estimates for the crust and upper

  1. Applying Public Health Frameworks to Advance the Promotion of Mental Health Among Asian American Children

    PubMed Central

    Huang, Keng-Yen; Calzada, Esther; Kamboukos, Dimitra; Rhule, Dana; Sharma, Kirsten Cullen; Cheng, Sabrina; Brotman, Laurie Miller

    2014-01-01

    Asian American (ASA) children experience high rates of mental health problems. Although there is a pressing need to utilize population approaches, emerging frameworks from the fields of public and population health have not been applied to ASA children. This paper addresses this gap by first discussing applications of the National Prevention Strategy (NPS), a population strategy developed from the Social Determinants of Health perspective, to guide ASA prevention work. Next, we provide a practical example to illustrate how the NPS can be applied to prevention program design (using ParentCorps as an example) and dissemination and implementation processes to broadly address ASA children's mental health needs. Finally, we present preliminary data on the feasibility of applying this population strategy to ASA families and a framework for researchers who are considering disseminating and implementing evidence-based programs to ASA or ethnic minority pediatric populations. PMID:25505500

  2. Recent Advances in Modeling Hugoniots with Cheetah

    NASA Astrophysics Data System (ADS)

    Glaesemann, K. R.; Fried, L. E.

    2006-07-01

    We describe improvements to the Cheetah thermochemical-kinetics code's equilibrium solver to enable it to find a wider range of thermodynamic states. Cheetah supports a wide range of elements, condensed detonation products, and gas phase reactions. Therefore, Cheetah can be applied to a wide range of shock problems involving both energetic and non-energetic materials. An improve equation of state is also introduced. New experimental validations of Cheetah's equation of state methodology have been performed, including both reacted and unreacted Hugoniots.

  3. Recent Advances in Modeling Hugoniots with Cheetah

    SciTech Connect

    Glaesemann, K R; Fried, L E

    2005-07-26

    We describe improvements to the Cheetah thermochemical-kinetics code's equilibrium solver to enable it to find a wider range of thermodynamic states. Cheetah supports a wide range of elements, condensed detonation products, and gas phase reactions. Therefore, Cheetah can be applied to a wide range of shock problems involving both energetic and non-energetic materials. An improve equation of state is also introduced. New experimental validations of Cheetah's equation of state methodology have been performed, including both reacted and unreacted Hugoniots.

  4. MixSIAR: advanced stable isotope mixing models in R

    EPA Science Inventory

    Background/Question/Methods The development of stable isotope mixing models has coincided with modeling products (e.g. IsoSource, MixSIR, SIAR), where methodological advances are published in parity with software packages. However, while mixing model theory has recently been ex...

  5. MixSIAR: advanced stable isotope mixing models in R

    EPA Science Inventory

    Background/Question/Methods The development of stable isotope mixing models has coincided with modeling products (e.g. IsoSource, MixSIR, SIAR), where methodological advances are published in parity with software packages. However, while mixing model theory has recently been ex...

  6. Advanced in turbulence physics and modeling by direct numerical simulations

    NASA Technical Reports Server (NTRS)

    Reynolds, W. C.

    1987-01-01

    The advent of direct numerical simulations of turbulence has opened avenues for research on turbulence physics and turbulence modeling. Direct numerical simulation provides values for anything that the scientist or modeler would like to know about the flow. An overview of some recent advances in the physical understanding of turbulence and in turbulence modeling obtained through such simulations is presented.

  7. Advances on genetic rat models of epilepsy.

    PubMed

    Serikawa, Tadao; Mashimo, Tomoji; Kuramoro, Takashi; Voigt, Birger; Ohno, Yukihiro; Sasa, Masashi

    2015-01-01

    Considering the suitability of laboratory rats in epilepsy research, we and other groups have been developing genetic models of epilepsy in this species. After epileptic rats or seizure-susceptible rats were sporadically found in outbred stocks, the epileptic traits were usually genetically-fixed by selective breeding. So far, the absence seizure models GAERS and WAG/Rij, audiogenic seizure models GEPR-3 and GEPR-9, generalized tonic-clonic seizure models IER, NER and WER, and Canavan-disease related epileptic models TRM and SER have been established. Dissection of the genetic bases including causative genes in these epileptic rat models would be a significant step toward understanding epileptogenesis. N-ethyl-N-nitrosourea (ENU) mutagenesis provides a systematic approach which allowed us to develop two novel epileptic rat models: heat-induced seizure susceptible (Hiss) rats with an Scn1a missense mutation and autosomal dominant lateral temporal epilepsy (ADLTE) model rats with an Lgi1 missense mutation. In addition, we have established episodic ataxia type 1 (EA1) model rats with a Kcna1 missense mutation derived from the ENU-induced rat mutant stock, and identified a Cacna1a missense mutation in a N-Methyl-N-nitrosourea (MNU)-induced mutant rat strain GRY, resulting in the discovery of episodic ataxia type 2 (EA2) model rats. Thus, epileptic rat models have been established on the two paths: 'phenotype to gene' and 'gene to phenotype'. In the near future, development of novel epileptic rat models will be extensively promoted by the use of sophisticated genome editing technologies.

  8. Advances on genetic rat models of epilepsy

    PubMed Central

    Serikawa, Tadao; Mashimo, Tomoji; Kuramoto, Takashi; Voigt, Birger; Ohno, Yukihiro; Sasa, Masashi

    2014-01-01

    Considering the suitability of laboratory rats in epilepsy research, we and other groups have been developing genetic models of epilepsy in this species. After epileptic rats or seizure-susceptible rats were sporadically found in outbred stocks, the epileptic traits were usually genetically-fixed by selective breeding. So far, the absence seizure models GAERS and WAG/Rij, audiogenic seizure models GEPR-3 and GEPR-9, generalized tonic-clonic seizure models IER, NER and WER, and Canavan-disease related epileptic models TRM and SER have been established. Dissection of the genetic bases including causative genes in these epileptic rat models would be a significant step toward understanding epileptogenesis. N-ethyl-N-nitrosourea (ENU) mutagenesis provides a systematic approach which allowed us to develop two novel epileptic rat models: heat-induced seizure susceptible (Hiss) rats with an Scn1a missense mutation and autosomal dominant lateral temporal epilepsy (ADLTE) model rats with an Lgi1 missense mutation. In addition, we have established episodic ataxia type 1 (EA1) model rats with a Kcna1 missense mutation derived from the ENU-induced rat mutant stock, and identified a Cacna1a missense mutation in a N-Methyl-N-nitrosourea (MNU)-induced mutant rat strain GRY, resulting in the discovery of episodic ataxia type 2 (EA2) model rats. Thus, epileptic rat models have been established on the two paths: ‘phenotype to gene’ and ‘gene to phenotype’. In the near future, development of novel epileptic rat models will be extensively promoted by the use of sophisticated genome editing technologies. PMID:25312505

  9. The SAFRAN-ISBA-MODCOU hydrometeorological model applied over France

    NASA Astrophysics Data System (ADS)

    Habets, F.; Boone, A.; Champeaux, J. L.; Etchevers, P.; FranchistéGuy, L.; Leblois, E.; Ledoux, E.; Le Moigne, P.; Martin, E.; Morel, S.; Noilhan, J.; Quintana Seguí, P.; Rousset-Regimbeau, F.; Viennot, P.

    2008-03-01

    The hydrometeorological model SIM consists of a meteorological analysis system (SAFRAN), a land surface model (ISBA), and a hydrogeological model (MODCOU). It generates atmospheric forcing at an hourly time step, and it computes water and surface energy budgets, the river flow at more than 900 river-gauging stations, and the level of several aquifers. SIM was extended over all of France in order to have a homogeneous nationwide monitoring of the water resources: it can therefore be used to forecast flood risk and to monitor drought risk over the entire nation. The hydrometeorological model was applied over a 10-year period from 1995 to 2005. In this paper the databases used by the SIM model are presented; then the 10-year simulation is assessed by using the observations of daily streamflow, piezometric head, and snow depth. This assessment shows that SIM is able to reproduce the spatial and temporal variabilities of the water fluxes. The efficiency is above 0.55 (reasonable results) for 66% of the simulated river gauges, and above 0.65 (rather good results) for 36% of them. However, the SIM system produces worse results during the driest years, which is more likely due to the fact that only few aquifers are simulated explicitly. The annual evolution of the snow depth is well reproduced, with a square correlation coefficient around 0.9 over the large altitude range in the domain. The streamflow observations were used to estimate the overall error of the simulated latent heat flux, which was estimated to be less than 4%.

  10. STARPAHC - Operational findings. [Space Technology Applied to Rural Papago Advanced Health Care

    NASA Technical Reports Server (NTRS)

    Belasco, N.; Pool, S. L.

    1976-01-01

    Delivery of quality health care to passengers of extended-mission spacecraft and to remote populations on earth (a major national problem) requires extending the knowledge and skills of the physician many kilometers distant from his physical location. The STARPAHC telemedicine system accomplishes this by using physician's assistants complemented with space technology in communications, data handling, and systems engineering. It is presently in operation and undergoing a 2-year evaluation on the Papago Indian Reservation, Arizona. Results have established its feasibility as a solution for remote area health care on earth, while providing information useful to the planners of advanced manned spacecraft missions.

  11. Recent Advances in the LEWICE Icing Model

    NASA Technical Reports Server (NTRS)

    Wright, William B.; Addy, Gene; Struk, Peter; Bartkus, Tadas

    2015-01-01

    This paper will describe two recent modifications to the Glenn ICE software. First, a capability for modeling ice crystals and mixed phase icing has been modified based on recent experimental data. Modifications have been made to the ice particle bouncing and erosion model. This capability has been added as part of a larger effort to model ice crystal ingestion in aircraft engines. Comparisons have been made to ice crystal ice accretions performed in the NRC Research Altitude Test Facility (RATFac). Second, modifications were made to the run back model based on data and observations from thermal scaling tests performed in the NRC Altitude Icing Tunnel.

  12. Dynamical behavior of the Niedermayer algorithm applied to Potts models

    NASA Astrophysics Data System (ADS)

    Girardi, D.; Penna, T. J. P.; Branco, N. S.

    2012-08-01

    In this work, we make a numerical study of the dynamic universality class of the Niedermayer algorithm applied to the two-dimensional Potts model with 2, 3, and 4 states. This algorithm updates clusters of spins and has a free parameter, E0, which controls the size of these clusters, such that E0=1 is the Metropolis algorithm and E0=0 regains the Wolff algorithm, for the Potts model. For -10, spins in different states may be added to the cluster but the dynamic behavior is less efficient than for the Wolff algorithm (E0=0). Therefore, our results show that the Wolff algorithm is the best choice for Potts models, when compared to the Niedermayer's generalization.

  13. Challenges of applying a comprehensive model of intervention fidelity.

    PubMed

    Bosak, Kelly A; Pozehl, Bunny; Yates, Bernice

    2012-06-01

    Applying a comprehensive model of fidelity to interventions delivered by information and communication technologies (ICTs) has multiple challenges. Fidelity must be considered in the design, implementation, evaluation, and reporting of the intervention. The fidelity strategies must address the unique aspects of the technology, including training providers to instruct participants to use the technology and provide standardized feedback, rather than delivering the intervention in person. Other challenges include the nonspecific effects resulting from participants accessing unintended content in interventions using the Internet. ICT allows participant receipt and enactment of intervention skills to be assessed by electronic evidence, rather than in-person observation. Interventions delivered by ICT are unique, and there is less control of participant interaction with various electronic components. Monitoring participant use and providing standardized feedback for receipt and enactment of intervention skills are key to ensuring fidelity. The final challenges involve evaluating and reporting fidelity of the intervention.

  14. Stability of Model Predictive Control applied to a Reservoir

    NASA Astrophysics Data System (ADS)

    van Nooijen, Ronald; Kolechkina, Alla

    2017-04-01

    Modern water management needs to deal with contraints and needs to use forecasts to anticipate on extreme events. One of the most popular techniques to achieve this is Model Predictive Control. The approach is widely applied and fairly successful. However, the question of stability of the resulting system is often not explicitly demonstrated. To examine ths aspect we consider a reservoir that serves two purposes: shipping and short term storage for flood prevention. For shipping a more or less constant water level is desired, while for flood prevention additional storage space will need to be freed up when the need arises. Under the assumption that we have a reliable short term forecast of storage needs, we will implement a simple MPC controller and show that the resulting controlled system is stable.

  15. Advanced relativistic VLBI model for geodesy

    NASA Astrophysics Data System (ADS)

    Soffel, Michael; Kopeikin, Sergei; Han, Wen-Biao

    2017-07-01

    Our present relativistic part of the geodetic VLBI model for Earthbound antennas is a consensus model which is considered as a standard for processing high-precision VLBI observations. It was created as a compromise between a variety of relativistic VLBI models proposed by different authors as documented in the IERS Conventions 2010. The accuracy of the consensus model is in the picosecond range for the group delay but this is not sufficient for current geodetic purposes. This paper provides a fully documented derivation of a new relativistic model having an accuracy substantially higher than one picosecond and based upon a well accepted formalism of relativistic celestial mechanics, astrometry and geodesy. Our new model fully confirms the consensus model at the picosecond level and in several respects goes to a great extent beyond it. More specifically, terms related to the acceleration of the geocenter are considered and kept in the model, the gravitational time-delay due to a massive body (planet, Sun, etc.) with arbitrary mass and spin-multipole moments is derived taking into account the motion of the body, and a new formalism for the time-delay problem of radio sources located at finite distance from VLBI stations is presented. Thus, the paper presents a substantially elaborated theoretical justification of the consensus model and its significant extension that allows researchers to make concrete estimates of the magnitude of residual terms of this model for any conceivable configuration of the source of light, massive bodies, and VLBI stations. The largest terms in the relativistic time delay which can affect the current VLBI observations are from the quadrupole and the angular momentum of the gravitating bodies that are known from the literature. These terms should be included in the new geodetic VLBI model for improving its consistency.

  16. Advanced relativistic VLBI model for geodesy

    NASA Astrophysics Data System (ADS)

    Soffel, Michael; Kopeikin, Sergei; Han, Wen-Biao

    2016-10-01

    Our present relativistic part of the geodetic VLBI model for Earthbound antennas is a consensus model which is considered as a standard for processing high-precision VLBI observations. It was created as a compromise between a variety of relativistic VLBI models proposed by different authors as documented in the IERS Conventions 2010. The accuracy of the consensus model is in the picosecond range for the group delay but this is not sufficient for current geodetic purposes. This paper provides a fully documented derivation of a new relativistic model having an accuracy substantially higher than one picosecond and based upon a well accepted formalism of relativistic celestial mechanics, astrometry and geodesy. Our new model fully confirms the consensus model at the picosecond level and in several respects goes to a great extent beyond it. More specifically, terms related to the acceleration of the geocenter are considered and kept in the model, the gravitational time-delay due to a massive body (planet, Sun, etc.) with arbitrary mass and spin-multipole moments is derived taking into account the motion of the body, and a new formalism for the time-delay problem of radio sources located at finite distance from VLBI stations is presented. Thus, the paper presents a substantially elaborated theoretical justification of the consensus model and its significant extension that allows researchers to make concrete estimates of the magnitude of residual terms of this model for any conceivable configuration of the source of light, massive bodies, and VLBI stations. The largest terms in the relativistic time delay which can affect the current VLBI observations are from the quadrupole and the angular momentum of the gravitating bodies that are known from the literature. These terms should be included in the new geodetic VLBI model for improving its consistency.

  17. A value analysis model applied to the management of amblyopia.

    PubMed Central

    Beauchamp, G R; Bane, M C; Stager, D R; Berry, P M; Wright, W W

    1999-01-01

    PURPOSE: To assess the value of amblyopia-related services by utilizing a health value model (HVM). Cost and quality criteria are evaluated in accordance with the interests of patients, physicians, and purchasers. METHODS: We applied an HVM to a hypothetical statistical ("median") child with amblyopia whose visual acuity is 20/80 and to a group of children with amblyopia who are managed by our practice. We applied the model to calculate the value of these services by evaluating the responses of patients and physicians and relating these responses to clinical outcomes. RESULTS: The consensus value of care for the hypothetical median child was calculated to be 0.406 (of 1.000). For those children managed in our practice, the calculated value is 0.682. Clinically, 79% achieved 20/40 or better visual acuity, and the mean final visual acuity was 0.2 logMAR (20/32). Value appraisals revealed significant concerns about the financial aspects of amblyopia-related services, particularly among physicians. Patients rated services more positively than did physicians. CONCLUSIONS: Amblyopia care is difficult, sustained, and important work that requires substantial sensitivity to and support of children and families. Compliance and early detection are essential to success. The value of amblyopia services is rated significantly higher by patients than by physicians. Relative to the measured value, amblyopia care is undercompensated. The HVM is useful to appraise clinical service delivery and its variation. The costs of failure and the benefits of success are high; high-value amblyopia care yields substantial dividends and should be commensurately compensated in the marketplace. PMID:10703133

  18. Carbon export algorithm advancements in models

    NASA Astrophysics Data System (ADS)

    Çağlar Yumruktepe, Veli; Salihoğlu, Barış

    2015-04-01

    The rate at which anthropogenic CO2 is absorbed by the oceans remains a critical question under investigation by climate researchers. Construction of a complete carbon budget, requires better understanding of air-sea exchanges and the processes controlling the vertical and horizontal transport of carbon in the ocean, particularly the biological carbon pump. Improved parameterization of carbon sequestration within ecosystem models is vital to better understand and predict changes in the global carbon cycle. Due to the complexity of processes controlling particle aggregation, sinking and decomposition, existing ecosystem models necessarily parameterize carbon sequestration using simple algorithms. Development of improved algorithms describing carbon export and sequestration, suitable for inclusion in numerical models is an ongoing work. Existing unique algorithms used in the state-of-the art ecosystem models and new experimental results obtained from mesocosm experiments and open ocean observations have been inserted into a common 1D pelagic ecosystem model for testing purposes. The model was implemented to the timeseries stations in the North Atlantic (BATS, PAP and ESTOC) and were evaluated with datasets of carbon export. Targetted topics of algorithms were PFT functional types, grazing and vertical movement of zooplankton, and remineralization, aggregation and ballasting dynamics of organic matter. Ultimately it is intended to feed improved algorithms to the 3D modelling community, for inclusion in coupled numerical models.

  19. An Advanced Sea-Floor Spreading Model.

    ERIC Educational Resources Information Center

    Dutch, Steven I.

    1986-01-01

    Describes models which (1) illustrate spreading that varies in rate from place to place; (2) clearly show transform faults as arcs of small circles; and (3) illustrate what happens near a pole of rotation. The models are easy to construct and have been well received by students. (JN)

  20. Advanced robotics technology applied to mixed waste characterization, sorting and treatment

    SciTech Connect

    Wilhelmsen, K.; Hurd, R.; Grasz, E.

    1994-04-01

    There are over one million cubic meters of radioactively contaminated hazardous waste, known as mixed waste, stored at Department of Energy facilities. Researchers at Lawrence Livermore National Laboratory (LLNL) are developing methods to safely and efficiently treat this type of waste. LLNL has automated and demonstrated a means of segregating items in a mixed waste stream. This capability incorporates robotics and automation with advanced multi-sensor information for autonomous and teleoperational handling of mixed waste items with previously unknown characteristics. The first phase of remote waste stream handling was item singulation; the ability to remove individual items of heterogeneous waste directly from a drum, box, bin, or pile. Once objects were singulated, additional multi-sensory information was used for object classification and segregation. In addition, autonomous and teleoperational surface cleaning and decontamination of homogeneous metals has been demonstrated in processing mixed waste streams. The LLNL waste stream demonstration includes advanced technology such as object classification algorithms, identification of various metal types using active and passive gamma scans and RF signatures, and improved teleoperational and autonomous grasping of waste objects. The workcell control program used an off-line programming system as a server to perform both simulation control as well as actual hardware control of the workcell. This paper will discuss the motivation for remote mixed waste stream handling, the overall workcell layout, sensor specifications, workcell supervisory control, 3D vision based automated grasp planning and object classification algorithms.

  1. Advances in Murine Models of Diabetic Nephropathy

    PubMed Central

    Kong, Li-li; Wu, Hao; Cui, Wen-peng; Zhou, Wen-hua; Luo, Ping; Sun, Jing; Yuan, Hang; Miao, Li-ning

    2013-01-01

    Diabetic nephropathy (DN) is one of the microvascular complications of both type 1 and type 2 diabetes, which is also associated with a poor life expectancy of diabetic patients. However, the pathogenesis of DN is still unclear. Thus, it is of great use to establish appropriate animal models of DN for doing research on pathogenesis and developing novel therapeutic strategies. Although a large number of murine models of DN including artificially induced, spontaneous, and genetically engineered (knockout and transgenic) animal models have been developed, none of them develops renal changes sufficiently reflecting those seen in humans. Here we review the identified murine models of DN from the aspects of genetic background, type of diabetes, method of induction, gene deficiency, animal age and gender, kidney histopathology, and phenotypic alterations in the hope of enhancing our comprehension of genetic susceptibility and molecular mechanisms responsible for this disease and providing new clues as to how to choose appropriate animal models of DN. PMID:23844375

  2. Recent modelling advances for ultrasonic TOFD inspections

    NASA Astrophysics Data System (ADS)

    Darmon, Michel; Ferrand, Adrien; Dorval, Vincent; Chatillon, Sylvain; Lonné, Sébastien

    2015-03-01

    The ultrasonic TOFD (Time of Flight Diffraction) Technique is commonly used to detect and characterize disoriented cracks using their edge diffraction echoes. An overview of the models integrated in the CIVA software platform and devoted to TOFD simulation is presented. CIVA allows to predict diffraction echoes from complex 3D flaws using a PTD (Physical Theory of Diffraction) based model. Other dedicated developments have been added to simulate lateral waves in 3D on planar entry surfaces and in 2D on irregular surfaces by a ray approach. Calibration echoes from Side Drilled Holes (SDHs), specimen echoes and shadowing effects from flaws can also been modelled. Some examples of theoretical validation of the models are presented. In addition, experimental validations have been performed both on planar blocks containing calibration holes and various notches and also on a specimen with an irregular entry surface and allow to draw conclusions on the validity of all the developed models.

  3. Recent modelling advances for ultrasonic TOFD inspections

    SciTech Connect

    Darmon, Michel; Ferrand, Adrien; Dorval, Vincent; Chatillon, Sylvain; Lonné, Sébastien

    2015-03-31

    The ultrasonic TOFD (Time of Flight Diffraction) Technique is commonly used to detect and characterize disoriented cracks using their edge diffraction echoes. An overview of the models integrated in the CIVA software platform and devoted to TOFD simulation is presented. CIVA allows to predict diffraction echoes from complex 3D flaws using a PTD (Physical Theory of Diffraction) based model. Other dedicated developments have been added to simulate lateral waves in 3D on planar entry surfaces and in 2D on irregular surfaces by a ray approach. Calibration echoes from Side Drilled Holes (SDHs), specimen echoes and shadowing effects from flaws can also been modelled. Some examples of theoretical validation of the models are presented. In addition, experimental validations have been performed both on planar blocks containing calibration holes and various notches and also on a specimen with an irregular entry surface and allow to draw conclusions on the validity of all the developed models.

  4. Seismic modeling of Earth's 3D structure: Recent advancements

    NASA Astrophysics Data System (ADS)

    Ritsema, J.

    2008-12-01

    Global models of Earth's seismic structure continue to improve due to the growth of seismic data sets, implementation of advanced wave propagations theories, and increased computational power. In my presentation, I will summarize seismic tomography results from the past 5-10 years. I will compare the most recent P and S velocity models, discuss model resolution and model interpretation, and present an, admittedly biased, list of research directions required to develop the next generation 3D models.

  5. An advanced terrain modeler for an autonomous planetary rover

    NASA Technical Reports Server (NTRS)

    Hunter, E. L.

    1980-01-01

    A roving vehicle capable of autonomously exploring the surface of an alien world is under development and an advanced terrain modeler to characterize the possible paths of the rover as hazardous or safe is presented. This advanced terrain modeler has several improvements over the Troiani modeler that include: a crosspath analysis, better determination of hazards on slopes, and methods for dealing with missing returns at the extremities of the sensor field. The results from a package of programs to simulate the roving vehicle are then examined and compared to results from the Troiani modeler.

  6. Advances and applications of occupancy models

    USGS Publications Warehouse

    Bailey, Larissa; MacKenzie, Darry I.; Nichols, James D.

    2013-01-01

    Summary: The past decade has seen an explosion in the development and application of models aimed at estimating species occurrence and occupancy dynamics while accounting for possible non-detection or species misidentification. We discuss some recent occupancy estimation methods and the biological systems that motivated their development. Collectively, these models offer tremendous flexibility, but simultaneously place added demands on the investigator. Unlike many mark–recapture scenarios, investigators utilizing occupancy models have the ability, and responsibility, to define their sample units (i.e. sites), replicate sampling occasions, time period over which species occurrence is assumed to be static and even the criteria that constitute ‘detection’ of a target species. Subsequent biological inference and interpretation of model parameters depend on these definitions and the ability to meet model assumptions. We demonstrate the relevance of these definitions by highlighting applications from a single biological system (an amphibian–pathogen system) and discuss situations where the use of occupancy models has been criticized. Finally, we use these applications to suggest future research and model development.

  7. Recent advances in topside profile modeling

    NASA Astrophysics Data System (ADS)

    Pulinets, S. A.; Depuev, V. H.; Karpachev, A. T.; Radicella, S. M.; Danilkin, N. P.

    A parameterized model for topside profile was developed based on the Epstein function approximation. Using the Intercosmos-19 database, model parameters were obtained for different geophysical conditions, including strong-magnetic storms. In some specific conditions the F3 layer was observed on topside ionograms. A physical explanation is proposed as well as results based on modeling approach. Topside ionograms from the sounder on MIR Space Station were studied. Some exotic cases are presented including oblique propagation, station position under the peak height etc. Peak height global distribution is described as well as neutral wind parameters derived from the topside peak height values.

  8. Enabling Technologies for Advanced Soft Tissue Modeling

    DTIC Science & Technology

    2006-09-01

    Tools for measuring soft tissue properties. Workshop on Reality- Based Modeling of Tissues for Simulation and Robot -Assisted Surgery , at IEEE/RSJ IROS...protocols, mathematical models and tools, and validation techniques to determine and describe the biomechanical behavior of living tissues. The...surgical simulation systems that allow new doctors to experience their first surgeries without risk to real patients. They can be implemented in

  9. Advanced Concepts for Underwater Acoustic Channel Modeling

    NASA Astrophysics Data System (ADS)

    Etter, P. C.; Haas, C. H.; Ramani, D. V.

    2014-12-01

    This paper examines nearshore underwater-acoustic channel modeling concepts and compares channel-state information requirements against existing modeling capabilities. This process defines a subset of candidate acoustic models suitable for simulating signal propagation in underwater communications. Underwater-acoustic communications find many practical applications in coastal oceanography, and networking is the enabling technology for these applications. Such networks can be formed by establishing two-way acoustic links between autonomous underwater vehicles and moored oceanographic sensors. These networks can be connected to a surface unit for further data transfer to ships, satellites, or shore stations via a radio-frequency link. This configuration establishes an interactive environment in which researchers can extract real-time data from multiple, but distant, underwater instruments. After evaluating the obtained data, control messages can be sent back to individual instruments to adapt the networks to changing situations. Underwater networks can also be used to increase the operating ranges of autonomous underwater vehicles by hopping the control and data messages through networks that cover large areas. A model of the ocean medium between acoustic sources and receivers is called a channel model. In an oceanic channel, characteristics of the acoustic signals change as they travel from transmitters to receivers. These characteristics depend upon the acoustic frequency, the distances between sources and receivers, the paths followed by the signals, and the prevailing ocean environment in the vicinity of the paths. Properties of the received signals can be derived from those of the transmitted signals using these channel models. This study concludes that ray-theory models are best suited to the simulation of acoustic signal propagation in oceanic channels and identifies 33 such models that are eligible candidates.

  10. Recent advances in modeling Hugoniots with Cheetah

    NASA Astrophysics Data System (ADS)

    Glaesemann, Kurt

    2005-07-01

    The detonation of an energetic material is the result of a complex interaction between kinetic chemical reactions and thermodynamic chemical equilibrium. Unfortunately, little is known concerning the detailed chemical kinetics of reacting energetic materials. Cheetah uses rate laws to treat species with the slowest chemical reactions, while assuming other chemical species are in equilibrium. Cheetah supports a wide range of elements and condensed detonation products and can also be applied to gas phase reactions. Improvements have been made to Cheetah's equilibrium solver, that allow it to find a wider range of thermodynamic states. Many of the difficulties experienced by users in earlier versions of Cheetah have been fixed. New capabilities have also been added. The ultimate result is a code that can be applied to a wide range of shock problems involving both energetic and non-energetic materials. New experimental validations of Cheetah's equation of state methodology have been performed, including both reacted and unreacted Hugoniots. This work was performed under the auspices of the U.S. Department of Energy by the University of California Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.

  11. Advanced Electron Holography Applied to Electromagnetic Field Study in Materials Science.

    PubMed

    Shindo, Daisuke; Tanigaki, Toshiaki; Park, Hyun Soon

    2016-11-17

    Advances and applications of electron holography to the study of electromagnetic fields in various functional materials are presented. In particular, the development of split-illumination electron holography, which introduces a biprism in the illumination system of a holography electron microscope, enables highly accurate observations of electromagnetic fields and the expansion of the observable area. First, the charge distributions on insulating materials were studied by using split-illumination electron holography and including a mask in the illumination system. Second, the three-dimensional spin configurations of skyrmion lattices in a helimagnet were visualized by using a high-voltage holography electron microscope. Third, the pinning of the magnetic flux lines in a high-temperature superconductor YBa2 Cu3 O7-y was analyzed by combining electron holography and scanning ion microscopy. Finally, the dynamic accumulation and collective motions of electrons around insulating biomaterial surfaces were observed by utilizing the amplitude reconstruction processes of electron holography.

  12. Applying Precision Medicine and Immunotherapy Advances from Oncology to Host-Directed Therapies for Infectious Diseases

    PubMed Central

    Mahon, Robert N.; Hafner, Richard

    2017-01-01

    To meet the challenges of increasing antimicrobial resistance, the infectious disease community needs innovative therapeutics. Precision medicine and immunotherapies are transforming cancer therapeutics by targeting the regulatory signaling pathways that are involved not only in malignancies but also in the metabolic and immunologic function of the tumor microenvironment. Infectious diseases target many of the same regulatory pathways as they modulate host metabolic functions for their own nutritional requirements and to impede host immunity. These similarities and the advances made in precision medicine and immuno-oncology that are relevant for the current development of host-directed therapies (HDTs) to treat infectious diseases are discussed. To harness this potential, improvements in drug screening methods and development of assays that utilize the research tools including high throughput multiplexes already developed by oncology are essential. A multidisciplinary approach that brings together immunologists, infectious disease specialists, and oncologists will be necessary to fully develop the potential of HDTs. PMID:28706516

  13. Cohesive model applied to fracture propagation in Indiana Limestone

    NASA Astrophysics Data System (ADS)

    Dewers, T. A.; Rinehart, A. J.; Bishop, J. E.

    2014-12-01

    We apply a cohesive fracture (CF) model to results of short-rod (SR), notched 3-point-bend (N3PB) tests, and Brazil tests in Indiana Limestone. Calibration and validation of the model are performed within a commercial finite element modeling platform. By using a linear traction-displacement softening response for a defined fracture-opening displacement (w1) following peak tensile stress (σcrit), the CF model numerically lumps different spatially distributed inelastic processes occurring at and around fracture tips into a thin zone within an elastic domain. Both the SR and the N3PB test specimen geometries use a notch partway through the sample to control the location of fracture propagation. We develop a mesh for both the SR and N3PB geometries with a narrow cohesive zone in the center of notches. From the Brazil tests, we find a tensile splitting stress (σsplit) of 5.9 MPa. We use a σsplit as the peak tensile stress (σcrit) for all simulations. The Young's modulus (E) and the critical crack opening distance (w1) of the CF model are calibrated against the SR data. The model successfully captures the elastic, yield, peak, and initial and late failure behavior and compares favorably against the N3PB tests. Differences in force-displacement and crack propagation are primarily caused by: more mixed-mode (shear and opening) crack propagation in N3PB than in SR tests, causing a higher peak; and transition from compression (high E) to tension (low E) in a larger volume of the N3PB sample than in the SR geometry. This material is based upon work supported as part of the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001114. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy

  14. Advanced Space Propulsion System Flowfield Modeling

    NASA Technical Reports Server (NTRS)

    Smith, Sheldon

    1998-01-01

    Solar thermal upper stage propulsion systems currently under development utilize small low chamber pressure/high area ratio nozzles. Consequently, the resulting flow in the nozzle is highly viscous, with the boundary layer flow comprising a significant fraction of the total nozzle flow area. Conventional uncoupled flow methods which treat the nozzle boundary layer and inviscid flowfield separately by combining the two calculations via the influence of the boundary layer displacement thickness on the inviscid flowfield are not accurate enough to adequately treat highly viscous nozzles. Navier Stokes models such as VNAP2 can treat these flowfields but cannot perform a vacuum plume expansion for applications where the exhaust plume produces induced environments on adjacent structures. This study is built upon recently developed artificial intelligence methods and user interface methodologies to couple the VNAP2 model for treating viscous nozzle flowfields with a vacuum plume flowfield model (RAMP2) that is currently a part of the Plume Environment Prediction (PEP) Model. This study integrated the VNAP2 code into the PEP model to produce an accurate, practical and user friendly tool for calculating highly viscous nozzle and exhaust plume flowfields.

  15. Phenomenological Modeling of Infrared Sources: Recent Advances

    NASA Technical Reports Server (NTRS)

    Leung, Chun Ming; Kwok, Sun (Editor)

    1993-01-01

    Infrared observations from planned space facilities (e.g., ISO (Infrared Space Observatory), SIRTF (Space Infrared Telescope Facility)) will yield a large and uniform sample of high-quality data from both photometric and spectroscopic measurements. To maximize the scientific returns of these space missions, complementary theoretical studies must be undertaken to interpret these observations. A crucial step in such studies is the construction of phenomenological models in which we parameterize the observed radiation characteristics in terms of the physical source properties. In the last decade, models with increasing degree of physical realism (in terms of grain properties, physical processes, and source geometry) have been constructed for infrared sources. Here we review current capabilities available in the phenomenological modeling of infrared sources and discuss briefly directions for future research in this area.

  16. Models of advance directives in mental health care: stakeholder views.

    PubMed

    Atkinson, Jacqueline M; Garner, Helen C; Gilmour, W Harper

    2004-08-01

    The aim of this study was to examine perceptions of the place of advance directives in mental health care. Postal survey of stakeholders was carried out to assess their views on different models of advance directives in mental health care. A total of 473 responded. In all, 28% of psychiatrists thought advance directives were needed compared to 89% of voluntary organisations and above two-thirds of the other stakeholder groups. There were clear tensions between patient "autonomy" and "right to treatment" which underpin many of the concerns raised. Autonomy provided by advance directive can be contrasted with a co-operative partnership approach to advance planning. The legal status of advance directives is important for some people in relation to treatment refusal. There was general concern about the practical issues surrounding their implementation. There is a wide range of views in all stakeholder groups about the possible form advance directives should take. Although there is a widespread desire to increase patient involvement in treatment decisions, which advance directives could possibly help to realise, they may also have unwanted consequences for mental health services and individuals.

  17. Essays on Applied Resource Economics Using Bioeconomic Optimization Models

    NASA Astrophysics Data System (ADS)

    Affuso, Ermanno

    With rising demographic growth, there is increasing interest in analytical studies that assess alternative policies to provide an optimal allocation of scarce natural resources while ensuring environmental sustainability. This dissertation consists of three essays in applied resource economics that are interconnected methodologically within the agricultural production sector of Economics. The first chapter examines the sustainability of biofuels by simulating and evaluating an agricultural voluntary program that aims to increase the land use efficiency in the production of biofuels of first generation in the state of Alabama. The results show that participatory decisions may increase the net energy value of biofuels by 208% and reduce emissions by 26%; significantly contributing to the state energy goals. The second chapter tests the hypothesis of overuse of fertilizers and pesticides in U.S. peanut farming with respect to other inputs and address genetic research to reduce the use of the most overused chemical input. The findings suggest that peanut producers overuse fungicide with respect to any other input and that fungi resistant genetically engineered peanuts may increase the producer welfare up to 36.2%. The third chapter implements a bioeconomic model, which consists of a biophysical model and a stochastic dynamic recursive model that is used to measure potential economic and environmental welfare of cotton farmers derived from a rotation scheme that uses peanut as a complementary crop. The results show that the rotation scenario would lower farming costs by 14% due to nitrogen credits from prior peanut land use and reduce non-point source pollution from nitrogen runoff by 6.13% compared to continuous cotton farming.

  18. A National Strategy for Advancing Climate Modeling

    SciTech Connect

    Dunlea, Edward; Elfring, Chris

    2012-12-04

    Climate models are the foundation for understanding and projecting climate and climate-related changes and are thus critical tools for supporting climate-related decision making. This study developed a holistic strategy for improving the nation's capability to accurately simulate climate and related Earth system changes on decadal to centennial timescales. The committee's report is a high level analysis, providing a strategic framework to guide progress in the nation's climate modeling enterprise over the next 10-20 years. This study was supported by DOE, NSF, NASA, NOAA, and the intelligence community.

  19. Modeling Innovations Advance Wind Energy Industry

    NASA Technical Reports Server (NTRS)

    2009-01-01

    In 1981, Glenn Research Center scientist Dr. Larry Viterna developed a model that predicted certain elements of wind turbine performance with far greater accuracy than previous methods. The model was met with derision from others in the wind energy industry, but years later, Viterna discovered it had become the most widely used method of its kind, enabling significant wind energy technologies-like the fixed pitch turbines produced by manufacturers like Aerostar Inc. of Westport, Massachusetts-that are providing sustainable, climate friendly energy sources today.

  20. Applying the INN model to the MaxClique problem

    SciTech Connect

    Grossman, T.

    1993-09-01

    Max-Clique is the problem of finding the largest clique in a given graph. It is not only NP-hard, but, as recent results suggest, even hard to approximate. Nevertheless it is still very important to develop and test practical algorithms that will find approximate solutions for the maximum clique problem on various graphs stemming from numerous applications. Indeed, many different types of algorithmic approaches are applied to that problem. Several neural networks and related algorithms were applied recently to combinatorial optimization problems in general and to the Max-Clique problem in particular. These neural nets are dynamical system which minimize a cost (or computational ``energy``) function that represents the optimization problem, the Max-Clique in our case. Therefore they all belong to the class of integer programming algorithms surveyed in the Pardalos and Xue review. The work presented here is a development and improvement of a neural network algorithm that was introduced recently. In the previous work, we have considered two Hopfield type neural networks, the INN and the HcN, and their application to the max-clique problem. In this paper, I concentrate on the INN network and present an improved version of the t-A algorithm that was introduced in. The rest of this paper is organized as follows: in section 2, I describe the INN model and how it implements a given graph. In section 3, it is characterized in terms of graph theory. In particular, the stable states of the network are mapped to the maximal cliques of its underling graph. In section 4, I present the t-Annealing algorithm and an improved version of it, the Adaptive t-Annealing. Several experiments done with these algorithms on benchmark graphs are reported in section 5, and the efficiency of the new algorithm is demonstrated. I conclude with a short discussion.

  1. [Research advances in animal models of intervertebral disc degeneration].

    PubMed

    Zhang, Wenli; Liu, Hao; Li, Tanzhu

    2007-11-01

    To review the research advances in animal models of human disc degeneration. The relative articles in recent years were extensively reviewed. Studies both at home and abroad were analyzed and classified. The advantages and disadvantages of each method were compared. Studies were classified as either experimentally induced models or spontaneous models. The induced models were subdivided as mechanical (alteration of forces on the normal disc), structural (injury or chemical alteration) and genetically induced models. Spontaneous models included those animals that naturally developed degenerative disc disease. Animal model of intervertebral disc degeneration is an important path for revealing the pathogenesis of human disc degeneration, and play an important role in testing novel interventions. With recent advances in the relevance of animal models and humans, it has a great prospect in study of human disc degeneration.

  2. Smart Engines Via Advanced Model Based Controls

    SciTech Connect

    Allain, Marc

    2000-08-20

    A ''new'' process for developing control systems - Less engine testing - More robust control system - Shorter development cycle time - ''Smarter'' approach to engine control - On-board models describe engine behavior - Shorter, systematic calibration process - Customer and legislative requirements designed-in.

  3. Recent advances in applying Free Vortex Sheet theory to the estimation of vortex flow aerodynamics

    NASA Technical Reports Server (NTRS)

    Luckring, J. M.; Schoonover, W. E., Jr.; Frink, N. T.

    1982-01-01

    Free Vortex Sheet theory has been applied to a variety of configurations for the estimation of three-dimensional pressure distributions for wings developing separation-induced leading-edge vortex flows. Correlations with experiment show reasonable estimates for the effects of compressibility, side-slip, side edges, swept-wing blast-induced loads, and leading-edge vortex flaps. Theoretical studies expand upon these correlations to show general aerodynamic trends. Consideration is also given to simple, yet effective techniques which expedite convergence and therefore reduce computational expense.

  4. Advances in wind erosion modelling in Europe

    NASA Astrophysics Data System (ADS)

    Borrelli, Pasquale; Lugato, Emanuele; Alewell, Christine; Montanarella, Luca; Panagos, Panos

    2017-04-01

    Soil erosion by wind is a serious environmental problem often resulting in severe forms of soil degradation. Wind erosion is also a phenomenon relevant for Europe, although this land degradation process has been overlooked until very recently. The state-of-the-art literature presents wind erosion as a process that locally affects the semi-arid areas of the Mediterranean region as well as the temperate climate areas of the northern European countries. Actual observations, field measurements and modelling assessments, however, are all extremely limited and highly unequally distributed across Europe. As a result, we currently lack comprehensive understanding about where and when wind erosion occurs in Europe, and the intensity of erosion that poses a threat to agricultural productivity. Today's challenge is to integrate the insights of local experiments and field-scale models into a new generation of large-scale wind erosion models. While naturally being less accurate than field-scale models, these large-scale modelling approaches still provide essential knowledge about where and when wind erosion occurs and can disclose the level of risk for agricultural productivity in specific areas. Here, we present a geographic information system (GIS) version of the RWEQ (named GIS-RWEQ) to quantitatively assess soil loss by wind over large study areas (Land Degradation & Development, DOI: 10.1002/ldr.2588). The model designed to predict the daily soil loss potential at a ca. 1 km2 spatial resolution shows high consistency with local measurements reported in literature. The average soil loss predicted by GIS-RWEQ for the European arable land totals 62 million Mg yr-1, with an average area-specific soil loss of 0.53 Mg yr-1. The JRC model RUSLE2015, for the same area estimates 295 million Mg yr-1 of soil loss due to water erosion. Notably, soil loss by wind erosion in the European arable land could be as high as 20% of water erosion, even though the areas affected are mainly

  5. Measurement and modeling of advanced coal conversion processes

    SciTech Connect

    Solomon, P.R.; Serio, M.A.; Hamblen, D.G.; Smoot, L.D.; Brewster, B.S. Brigham Young Univ., Provo, UT )

    1991-01-01

    The overall objective of this program is the development of predictive capability for the design, scale up, simulation, control and feedstock evaluation in advanced coal conversion devices. This program will merge significant advances made in measuring and quantitatively describing the mechanisms in coal conversion behavior. Comprehensive computer codes for mechanistic modeling of entrained-bed gasification. Additional capabilities in predicting pollutant formation will be implemented and the technology will be expanded to fixed-bed reactors.

  6. Advances in developing molecular-diagnostic tools for strongyloid nematodes of equids: fundamental and applied implications.

    PubMed

    Gasser, Robin B; Hung, Guo-Chiuan; Chilton, Neil B; Beveridge, Ian

    2004-02-01

    Infections of equids with parasitic nematodes of the order Strongylida (subfamilies Strongylinae and Cyathostominae) are of major veterinary importance. In last decades, the widespread use of drugs against these parasites has led to problems of resistance within the Cyathostominae, and to an increase in their prevalence and intensity of infection. Novel control strategies, based on improved knowledge of parasite biology and epidemiology, have thus become important. However, there are substantial limitations in the understanding of fundamental biological and systematic aspects of these parasites, which have been due largely to limitations in their specific identification and diagnosis using traditional, morphological approaches. Recently, there has been progress in the development of DNA-based approaches for the specific identification of strongyloids of equids for systematic studies and disease diagnosis. The present article briefly reviews information on the classification, biology, pathogenesis, epidemiology of equine strongyloids and the diagnosis of infections, highlights knowledge gaps in these areas, describes recent advances in the use of molecular techniques for the genetic characterisation, specific identification and differentiation of strongyloids of equids as a basis for fundamental investigations of the systematics, population biology and ecology.

  7. Advanced transformational analysis applied to e-beam proximity effect correction

    NASA Astrophysics Data System (ADS)

    Barouch, Eytan; Coifman, Ronald R.; Ma, Jimmy T.; Peckerar, Martin C.; Rokhlin, Vladimir

    1993-06-01

    In this paper we address the problem of dose correction in the data bases consistent with ultra- large-scale integration. It is shown that recent advances in transformation theory provide a natural platform on which to build these dose correctors. Specifically, transformation approaches making use of compactly supported, smooth basis functions are shown to be particularly suitable. This is a natural result of the evolution of mathematically based correctors currently in use. Previous work in Parikh, MacDonald and others employed global transform method to determine the values of 'corrected' dose. In most cases, the mathematical inversion is essentially ill posed, in other words, the exact pattern desired cannot be obtained using a finite Gaussian sum. In this paper a set of smooth basis elements of compact support are employed. The mathematically smooth form of the basis makes it easy to match doses at boundaries without Gibbs phenomenon. Thus the transform field can be partitioned for optimum speed. Consequently, while most transformation complexities are of order N6 (the inversion of an N2 X N2 matrix) where N2 is the number of grid points characterizing the database, we developed an algorithm of complexity N2 log N. A method of dose field bias is employed to stem the requests for negative dose. The heart of the numerical process is essentially based on an adapted fast non-uniform-grid Fourier Transform combined with proper filtering and geometric localization methods. Several examples are given.

  8. Benefits associated with advanced technologies applied to a high-speed civil transport concept

    NASA Technical Reports Server (NTRS)

    Ozoroski, L. P.; Shields, E. W.; Fenbert, J. W.; Mcelroy, M. O.

    1993-01-01

    Results of a first-order assessment of the mission performance benefits associated with the technology improvements and goals of the Phase II High-Speed Research (HSR) Program are presented. A breakdown of the four major disciplines resulted in the following estimated TOGW savings from the 1990 vehicle: propulsion at 14.3 percent, structures at 11.7 percent, flight-deck systems at 4.0 percent, and aerodynamics at 15.0 percent. Based on 100 percent success of the HSR Phase II proposed technology advancements, the overall combined impact is estimated to result in a 45 percent reduction in TOGW from a 1990 entry-into-service (EIS) date, which could result in a viable 2005 EIS vehicle with an acceptable TOGW that meets Stage III community noise restrictions. Through supersonic laminar flow control and the possible reduction in reserve fuel requirements resulting from synthetic vision capability, the potential exists for an additional 9.6 percent reduction in TOGW.

  9. Monte Carlo simulation models of breeding-population advancement.

    Treesearch

    J.N. King; G.R. Johnson

    1993-01-01

    Five generations of population improvement were modeled using Monte Carlo simulations. The model was designed to address questions that are important to the development of an advanced generation breeding population. Specifically we addressed the effects on both gain and effective population size of different mating schemes when creating a recombinant population for...

  10. Rodent models of TDP-43: Recent advances

    PubMed Central

    Tsao, William; Jeong, Yun Ha; Lin, Sophie; Ling, Jonathan; Price, Donald L.; Chiang, Po-Min; Wong, Philip C.

    2013-01-01

    Recently, missense mutations in the gene TARDBP encoding TDP-43 have been linked to familial ALS. The discovery of genes encoding these RNA binding proteins, such as TDP-43 and FUS/TLS, raised the notion that altered RNA metabolism is a major factor underlying the pathogenesis of ALS. To begin to unravel how mutations in TDP-43 cause dysfunction and death of motor neurons, investigators have employed both gain- and loss-of-function studies in rodent model systems. Here, we will summarize major findings from the initial sets of TDP-43 transgenic and knockout rodent models, identify their limitations, and point to future directions toward clarification of disease mechanism(s) and testing of therapeutic strategies that ultimately may lead to novel therapy for this devastating disease. PMID:22608070

  11. Advanced air revitalization system modeling and testing

    NASA Technical Reports Server (NTRS)

    Dall-Baumann, Liese; Jeng, Frank; Christian, Steve; Edeer, Marybeth; Lin, Chin

    1990-01-01

    To support manned lunar and Martian exploration, an extensive evaluation of air revitalization subsystems (ARS) is being conducted. The major operations under study include carbon dioxide removal and reduction; oxygen and nitrogen production, storage, and distribution; humidity and temperature control; and trace contaminant control. A comprehensive analysis program based on a generalized block flow model was developed to facilitate the evaluation of various processes and their interaction. ASPEN PLUS was used in modelling carbon dioxide removal and reduction. Several life support test stands were developed to test new and existing technologies for their potential applicability in space. The goal was to identify processes which use compact, lightweight equipment and maximize the recovery of oxygen and water. The carbon dioxide removal test stands include solid amine/vacuum desorption (SAVD), regenerative silver oxide chemisorption, and electrochemical carbon dioxide concentration (EDC). Membrane-based carbon dioxide removal and humidity control, catalytic reduction of carbon dioxide, and catalytic oxidation of trace contaminants were also investigated.

  12. Advanced Numerical Methods for NWP Models

    DTIC Science & Technology

    2008-09-30

    including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the...used to study tropical wave instability with a prescribed heat source representing ITCZ near the equator. The model configuration of the experiments...understanding and improvement of the physical parameterizations. Tests of NSEAM with idealized initial conditions show the breakdown of an unstable ITCZ profile

  13. Advanced Hybrid Modeling of Hall Thruster Plumes

    DTIC Science & Technology

    2010-06-16

    LVTF. A direct simulation Monte Carlo (DSMC) method3 is used to model collision dynamics, and a Particle-in-Cell ( PIC ) method4 is used to capture...cell ( PIC ) numerical methods on an axisymmetric grid.7 The code has been found to be effective in creating either time-averaged outputs of performance...here. The HPHall code performs an axisymmetric simulation, commonly referred to as “hybrid- PIC ,” treating the electrons via fluid approximation

  14. Integrated modeling of advanced optical systems

    NASA Technical Reports Server (NTRS)

    Briggs, Hugh C.; Needels, Laura; Levine, B. Martin

    1993-01-01

    This poster session paper describes an integrated modeling and analysis capability being developed at JPL under funding provided by the JPL Director's Discretionary Fund and the JPL Control/Structure Interaction Program (CSI). The posters briefly summarize the program capabilities and illustrate them with an example problem. The computer programs developed under this effort will provide an unprecedented capability for integrated modeling and design of high performance optical spacecraft. The engineering disciplines supported include structural dynamics, controls, optics and thermodynamics. Such tools are needed in order to evaluate the end-to-end system performance of spacecraft such as OSI, POINTS, and SMMM. This paper illustrates the proof-of-concept tools that have been developed to establish the technology requirements and demonstrate the new features of integrated modeling and design. The current program also includes implementation of a prototype tool based upon the CAESY environment being developed under the NASA Guidance and Control Research and Technology Computational Controls Program. This prototype will be available late in FY-92. The development plan proposes a major software production effort to fabricate, deliver, support and maintain a national-class tool from FY-93 through FY-95.

  15. Applying knowledge-anchored hypothesis discovery methods to advance clinical and translational research: the OAMiner project

    PubMed Central

    Jackson, Rebecca D; Best, Thomas M; Borlawsky, Tara B; Lai, Albert M; James, Stephen; Gurcan, Metin N

    2012-01-01

    The conduct of clinical and translational research regularly involves the use of a variety of heterogeneous and large-scale data resources. Scalable methods for the integrative analysis of such resources, particularly when attempting to leverage computable domain knowledge in order to generate actionable hypotheses in a high-throughput manner, remain an open area of research. In this report, we describe both a generalizable design pattern for such integrative knowledge-anchored hypothesis discovery operations and our experience in applying that design pattern in the experimental context of a set of driving research questions related to the publicly available Osteoarthritis Initiative data repository. We believe that this ‘test bed’ project and the lessons learned during its execution are both generalizable and representative of common clinical and translational research paradigms. PMID:22647689

  16. Applying Quality Function Deployment Model in Burn Unit Service Improvement.

    PubMed

    Keshtkaran, Ali; Hashemi, Neda; Kharazmi, Erfan; Abbasi, Mehdi

    2016-01-01

    Quality function deployment (QFD) is one of the most effective quality design tools. This study applies QFD technique to improve the quality of the burn unit services in Ghotbedin Hospital in Shiraz, Iran. First, the patients' expectations of burn unit services and their priorities were determined through Delphi method. Thereafter, burn unit service specifications were determined through Delphi method. Further, the relationships between the patients' expectations and service specifications and also the relationships between service specifications were determined through an expert group's opinion. Last, the final importance scores of service specifications were calculated through simple additive weighting method. The findings show that burn unit patients have 40 expectations in six different areas. These expectations are in 16 priority levels. Burn units also have 45 service specifications in six different areas. There are four-level relationships between the patients' expectations and service specifications and four-level relationships between service specifications. The most important burn unit service specifications have been identified in this study. The QFD model developed in the study can be a general guideline for QFD planners and executives.

  17. Applying optimal model selection in principal stratification for causal inference.

    PubMed

    Odondi, Lang'o; McNamee, Roseanne

    2013-05-20

    Noncompliance to treatment allocation is a key source of complication for causal inference. Efficacy estimation is likely to be compounded by the presence of noncompliance in both treatment arms of clinical trials where the intention-to-treat estimate provides a biased estimator for the true causal estimate even under homogeneous treatment effects assumption. Principal stratification method has been developed to address such posttreatment complications. The present work extends a principal stratification method that adjusts for noncompliance in two-treatment arms trials by developing model selection for covariates predicting compliance to treatment in each arm. We apply the method to analyse data from the Esprit study, which was conducted to ascertain whether unopposed oestrogen (hormone replacement therapy) reduced the risk of further cardiac events in postmenopausal women who survive a first myocardial infarction. We adjust for noncompliance in both treatment arms under a Bayesian framework to produce causal risk ratio estimates for each principal stratum. For mild values of a sensitivity parameter and using separate predictors of compliance in each arm, principal stratification results suggested that compliance with hormone replacement therapy only would reduce the risk for death and myocardial reinfarction by about 47% and 25%, respectively, whereas compliance with either treatment would reduce the risk for death by 13% and reinfarction by 60% among the most compliant. However, the results were sensitive to the user-defined sensitivity parameter.

  18. Advances in Geometric Acoustic Propagation Modeling Methods

    NASA Astrophysics Data System (ADS)

    Blom, P. S.; Arrowsmith, S.

    2013-12-01

    Geometric acoustics provides an efficient numerical method to model propagation effects. At leading order, one can identify ensonified regions and calculate celerities of the predicted arrivals. Beyond leading order, the solution of the transport equation provides a means to estimate the amplitude of individual acoustic phases. The auxiliary parameters introduced in solving the transport equation have been found to provide a means of identifying ray paths connecting source and receiver, or eigenrays, for non-planar propagation. A detailed explanation of the eigenray method will be presented as well as an application to predicting azimuth deviations for infrasonic data recorded during the Humming Roadrunner experiment of 2012.

  19. Modeling and analysis of advanced binary cycles

    SciTech Connect

    Gawlik, K.

    1997-12-31

    A computer model (Cycle Analysis Simulation Tool, CAST) and a methodology have been developed to perform value analysis for small, low- to moderate-temperature binary geothermal power plants. The value analysis method allows for incremental changes in the levelized electricity cost (LEC) to be determined between a baseline plant and a modified plant. Thermodynamic cycle analyses and component sizing are carried out in the model followed by economic analysis which provides LEC results. The emphasis of the present work is on evaluating the effect of mixed working fluids instead of pure fluids on the LEC of a geothermal binary plant that uses a simple Organic Rankine Cycle. Four resources were studied spanning the range of 265{degrees}F to 375{degrees}F. A variety of isobutane and propane based mixtures, in addition to pure fluids, were used as working fluids. This study shows that the use of propane mixtures at a 265{degrees}F resource can reduce the LEC by 24% when compared to a base case value that utilizes commercial isobutane as its working fluid. The cost savings drop to 6% for a 375{degrees}F resource, where an isobutane mixture is favored. Supercritical cycles were found to have the lowest cost at all resources.

  20. RECENT ADVANCES IN MACROMOLECULAR HYDRODYNAMIC MODELING

    PubMed Central

    Aragon, Sergio R.

    2010-01-01

    The modern implementation of the boundary element method (S.R. Aragon, J. Comput. Chem. 25(2004)1191–12055) has ushered unprecedented accuracy and precision for the solution of the Stokes equations of hydrodynamics with stick boundary conditions. This article begins by reviewing computations with the program BEST of smooth surface objects such as ellipsoids, the dumbbell, and cylinders that demonstrate that the numerical solution of the integral equation formulation of hydrodynamics yields very high precision and accuracy. When BEST is used for macromolecular computations, the limiting factor becomes the definition of the molecular hydrodynamic surface and the implied effective solvation of the molecular surface. Studies on 49 different proteins, ranging in molecular weight from 9 to over 400 kDa, have shown that a model using a 1.1 A thick hydration layer describes all protein transport properties very well for the overwhelming majority of them. In addition, this data implies that the crystal structure is an excellent representation of the average solution structure for most of them. In order to investigate the origin of a handful of significant discrepancies in some multimeric proteins (over −20% observed in the intrinsic viscosity), the technique of Molecular Dynamics simulation (MD) has been incorporated into the research program. A preliminary study of dimeric α-chymotrypsin using approximate implicit water MD is presented. In addition I describe the successful validation of modern protein force fields, ff03 and ff99SB, for the accurate computation of solution structure in explicit water simulation by comparison of trajectory ensemble average computed transport properties with experimental measurements. This work includes small proteins such as lysozyme, ribonuclease and ubiquitin using trajectories around 10 ns duration. We have also studied a 150 kDa flexible monoclonal IgG antibody, trastuzumab, with multiple independent trajectories encompassing over

  1. Use of Advanced Meteorological Model Output for Coastal Ocean Modeling in Puget Sound

    SciTech Connect

    Yang, Zhaoqing; Khangaonkar, Tarang; Wang, Taiping

    2011-06-01

    It is a great challenge to specify meteorological forcing in estuarine and coastal circulation modeling using observed data because of the lack of complete datasets. As a result of this limitation, water temperature is often not simulated in estuarine and coastal modeling, with the assumption that density-induced currents are generally dominated by salinity gradients. However, in many situations, temperature gradients could be sufficiently large to influence the baroclinic motion. In this paper, we present an approach to simulate water temperature using outputs from advanced meteorological models. This modeling approach was applied to simulate annual variations of water temperatures of Puget Sound, a fjordal estuary in the Pacific Northwest of USA. Meteorological parameters from North American Region Re-analysis (NARR) model outputs were evaluated with comparisons to observed data at real-time meteorological stations. Model results demonstrated that NARR outputs can be used to drive coastal ocean models for realistic simulations of long-term water-temperature distributions in Puget Sound. Model results indicated that the net flux from NARR can be further improved with the additional information from real-time observations.

  2. Advances in using MRI probes and sensors for in vivo cell tracking as applied to regenerative medicine

    PubMed Central

    Srivastava, Amit K.; Kadayakkara, Deepak K.; Bar-Shir, Amnon; Gilad, Assaf A.; McMahon, Michael T.; Bulte, Jeff W. M.

    2015-01-01

    The field of molecular and cellular imaging allows molecules and cells to be visualized in vivo non-invasively. It has uses not only as a research tool but in clinical settings as well, for example in monitoring cell-based regenerative therapies, in which cells are transplanted to replace degenerating or damaged tissues, or to restore a physiological function. The success of such cell-based therapies depends on several critical issues, including the route and accuracy of cell transplantation, the fate of cells after transplantation, and the interaction of engrafted cells with the host microenvironment. To assess these issues, it is necessary to monitor transplanted cells non-invasively in real-time. Magnetic resonance imaging (MRI) is a tool uniquely suited to this task, given its ability to image deep inside tissue with high temporal resolution and sensitivity. Extraordinary efforts have recently been made to improve cellular MRI as applied to regenerative medicine, by developing more advanced contrast agents for use as probes and sensors. These advances enable the non-invasive monitoring of cell fate and, more recently, that of the different cellular functions of living cells, such as their enzymatic activity and gene expression, as well as their time point of cell death. We present here a review of recent advancements in the development of these probes and sensors, and of their functioning, applications and limitations. PMID:26035841

  3. Advanced modeling and simulation to design and manufacture high performance and reliable advanced microelectronics and microsystems.

    SciTech Connect

    Nettleship, Ian (University of Pittsburgh, Pittsburgh, PA); Hinklin, Thomas; Holcomb, David Joseph; Tandon, Rajan; Arguello, Jose Guadalupe, Jr.; Dempsey, James Franklin; Ewsuk, Kevin Gregory; Neilsen, Michael K.; Lanagan, Michael (Pennsylvania State University, University Park, PA)

    2007-07-01

    An interdisciplinary team of scientists and engineers having broad expertise in materials processing and properties, materials characterization, and computational mechanics was assembled to develop science-based modeling/simulation technology to design and reproducibly manufacture high performance and reliable, complex microelectronics and microsystems. The team's efforts focused on defining and developing a science-based infrastructure to enable predictive compaction, sintering, stress, and thermomechanical modeling in ''real systems'', including: (1) developing techniques to and determining materials properties and constitutive behavior required for modeling; (2) developing new, improved/updated models and modeling capabilities, (3) ensuring that models are representative of the physical phenomena being simulated; and (4) assessing existing modeling capabilities to identify advances necessary to facilitate the practical application of Sandia's predictive modeling technology.

  4. A Study of Advanced Modern Control Techniques Applied to a Twin Rotor MIMO System

    NASA Astrophysics Data System (ADS)

    Phillips, Andrew E.

    The twin rotor MIMO system (TRMS) is a helicopter-like system that is restricted to two degrees of freedom, pitch and yaw. It is a complicated nonlinear, coupled, MIMO system used for the verification of control methods and observers. There have been many methods successfully applied to the system ranging from simple proportional integral derivative (PID) controllers, to machine learning algorithms, nonlinear control methods and other less explored methods like deadbeat control and various optimal methodologies. This thesis details the design procedure for two different control methods. The first is a suboptimal tracking controller using a linear quadratic regulator (LQR) with integral action. The second is the design of several adaptive sliding mode controller to provide robust tracking control of the TRMS. Once the design is complete the controllers are tested in simulation and their performance is compared against a PID controller experimentally. The performance of the controllers are also compared against other controllers in the literature. The ability of the sliding mode controllers (SMC) to suppress chattering is also be explored.

  5. Modeling of advanced ECLSS/ARS with ASPEN

    NASA Technical Reports Server (NTRS)

    Kolodney, M.; Lange, K. E.; Edeen, M. A.

    1991-01-01

    System-level ASPEN models were developed for the CO2 partial reduction subsystem and a bioregenerative life support subsystem (BRLSS). The individual component and subsystem models were integrated into three different system-level atmospheric revitalization subsystem (ARS) models: baseline physico-chemical, BRLSS, and partial reduction of Martian CO2. The Aspen models were based on FORTRAN interfaces necessary for integration with another program, G189A, to perform quasi-transient modeling. Detailed reactor models were prepared for the two CO2 reduction reactors (Bosch and Advanced Carbon Formation), and the low-temperature trace contaminant oxidation reactor.

  6. The scientific modeling assistant: An advanced software tool for scientific model building

    NASA Technical Reports Server (NTRS)

    Keller, Richard M.; Sims, Michael H.

    1991-01-01

    Viewgraphs on the scientific modeling assistant: an advanced software tool for scientific model building are presented. The objective is to build a specialized software tool to assist in scientific model-building.

  7. The scientific modeling assistant: An advanced software tool for scientific model building

    NASA Technical Reports Server (NTRS)

    Keller, Richard M.; Sims, Michael H.

    1991-01-01

    Viewgraphs on the scientific modeling assistant: an advanced software tool for scientific model building are presented. The objective is to build a specialized software tool to assist in scientific model-building.

  8. Atomistic Method Applied to Computational Modeling of Surface Alloys

    NASA Technical Reports Server (NTRS)

    Bozzolo, Guillermo H.; Abel, Phillip B.

    2000-01-01

    The formation of surface alloys is a growing research field that, in terms of the surface structure of multicomponent systems, defines the frontier both for experimental and theoretical techniques. Because of the impact that the formation of surface alloys has on surface properties, researchers need reliable methods to predict new surface alloys and to help interpret unknown structures. The structure of surface alloys and when, and even if, they form are largely unpredictable from the known properties of the participating elements. No unified theory or model to date can infer surface alloy structures from the constituents properties or their bulk alloy characteristics. In spite of these severe limitations, a growing catalogue of such systems has been developed during the last decade, and only recently are global theories being advanced to fully understand the phenomenon. None of the methods used in other areas of surface science can properly model even the already known cases. Aware of these limitations, the Computational Materials Group at the NASA Glenn Research Center at Lewis Field has developed a useful, computationally economical, and physically sound methodology to enable the systematic study of surface alloy formation in metals. This tool has been tested successfully on several known systems for which hard experimental evidence exists and has been used to predict ternary surface alloy formation (results to be published: Garces, J.E.; Bozzolo, G.; and Mosca, H.: Atomistic Modeling of Pd/Cu(100) Surface Alloy Formation. Surf. Sci., 2000 (in press); Mosca, H.; Garces J.E.; and Bozzolo, G.: Surface Ternary Alloys of (Cu,Au)/Ni(110). (Accepted for publication in Surf. Sci., 2000.); and Garces, J.E.; Bozzolo, G.; Mosca, H.; and Abel, P.: A New Approach for Atomistic Modeling of Pd/Cu(110) Surface Alloy Formation. (Submitted to Appl. Surf. Sci.)). Ternary alloy formation is a field yet to be fully explored experimentally. The computational tool, which is based on

  9. Constructing an advanced software tool for planetary atmospheric modeling

    NASA Technical Reports Server (NTRS)

    Keller, Richard M.; Sims, Michael; Podolak, Ester; Mckay, Christopher

    1990-01-01

    Scientific model building can be an intensive and painstaking process, often involving the development of large and complex computer programs. Despite the effort involved, scientific models cannot be easily distributed and shared with other scientists. In general, implemented scientific models are complex, idiosyncratic, and difficult for anyone but the original scientist/programmer to understand. We believe that advanced software techniques can facilitate both the model building and model sharing process. In this paper, we describe a prototype for a scientific modeling software tool that serves as an aid to the scientist in developing and using models. This tool includes an interactive intelligent graphical interface, a high level domain specific modeling language, a library of physics equations and experimental datasets, and a suite of data display facilities. Our prototype has been developed in the domain of planetary atmospheric modeling, and is being used to construct models of Titan's atmosphere.

  10. Heterogeneous Catalysis Applied To Advanced Oxidation Processes (AOPs) For Degradation of Organic Pollutants

    NASA Astrophysics Data System (ADS)

    Cotto-Maldonado, Maria del Carmen

    Water is an essencial resource for humankind and biomes. Actually, the pollution of the water resources, specially the contamination of the fresh water is great concern in our society. Develop of new and more efficient method for degradation of pollutant in water increase the research in this area, especially in the AOPs. During this investigation a comparison between different AOPs methods (photocatalysis, sono-Fenton and photo-Fenton) to determine the most efficient process of them was done. To reach our goal, different catalysts, namely TiO2 nanowires, TiO2 CNTs, ZnO nanoparticles, Fe2O3 nanowires and magnetite nanoparticles were synthesized and characterized by different techniques including FE-SEM, TGA, specific surface area (BET), XRD, Raman spectroscopy, XPS and magnetic susceptibility. Commercial and synthesized catalysts were used in photocatalysis, sono-Fenton and photo-Fenton processes for the degradation of model organic compounds (Methylene Blue, Rhodamine B, Methyl Orange, Gential Violet, Methyl Violet and p-aminobenzoic acid). According with the experimental results, no significant differences were observed between the photo-Fenton and sono-Fenton processes when the same catalysts were used. For the photocatalytic process, the more effective catalyst was TiO2NWs and for the sono-Fenton and photo-Fenton processes, the more effective catalyst was FeCl2.

  11. The saltus model applied to proportional reasoning data.

    PubMed

    Draney, Karen

    2007-01-01

    This chapter examines an application of the saltus model, a mixture model that was designed for the analysis of developmental data. Some background in the types of research for which such a model might be useful is discussed. The equations defining the model are given, as well as the model's relationship to the Rasch model and to other mixture models. An application of the saltus model to an example data set, collected using Noelting's orange juice mixtures tasks, is examined in detail, along with the control files necessary to run the software, and the output file it produced.

  12. Advances in Games Technology: Software, Models, and Intelligence

    ERIC Educational Resources Information Center

    Prakash, Edmond; Brindle, Geoff; Jones, Kevin; Zhou, Suiping; Chaudhari, Narendra S.; Wong, Kok-Wai

    2009-01-01

    Games technology has undergone tremendous development. In this article, the authors report the rapid advancement that has been observed in the way games software is being developed, as well as in the development of games content using game engines. One area that has gained special attention is modeling the game environment such as terrain and…

  13. Advances in Games Technology: Software, Models, and Intelligence

    ERIC Educational Resources Information Center

    Prakash, Edmond; Brindle, Geoff; Jones, Kevin; Zhou, Suiping; Chaudhari, Narendra S.; Wong, Kok-Wai

    2009-01-01

    Games technology has undergone tremendous development. In this article, the authors report the rapid advancement that has been observed in the way games software is being developed, as well as in the development of games content using game engines. One area that has gained special attention is modeling the game environment such as terrain and…

  14. Applying Advanced and Existing Sensors in Dealing with Potential Natural Disasters

    NASA Technical Reports Server (NTRS)

    Habib, Shahid

    2006-01-01

    As an integrated observing strategy, the concept of sensorweb for Earth observations is appealing in many aspects. For instance, by increasing the spatial and temporal coverage of observations from space and other vantage points, one can eventually aid in increasing the accuracy of the atmospheric models which are precursor to hurricane track prediction, volcanic eruption forecast, and trajectory path of transcontinental transport of dust, harmful nuclear and chemical plumes. In reality, there is little analysis available in terms of benefits, costs and optimized set of sensors needed to make these necessary observations. This is a complex problem that must be carefully studied and balanced over many boundaries such as science, defense, early warning, security, and surveillance. Simplistically, the sensorweb concept from the technological point of view alone has a great appeal in the defense, early warning and security applications. In fact, it can be relatively less expensive in per unit cost as opposed to building and deploying it for the scientific use. However, overall observing approach should not be singled out and aligned somewhat orthogonally to serve a particular need. On the other hand, the sensorweb should be designed and deployed to serve multiple subject areas and customers simultaneously; and can behave as directed measuring systems for both science and operational entities. Sensorweb can be designed to act as expert systems, and/or also provide a dedicated integrated surveillance network. Today, there is no system in the world that is fully integrated in terms of reporting timely multiple hazards warnings, computing the loss of life and property damage estimates, and is also designed to cater to everyone s needs. It is not an easier problem to undertake and more so is not practically solvable. At this time due to some recent events in the world, the scientific community, social scientists, and operational agencies are more cognizant and getting

  15. Applying Advanced and Existing Sensors in Dealing with Potential Natural Disasters

    NASA Technical Reports Server (NTRS)

    Habib, Shahid

    2006-01-01

    As an integrated observing strategy, the concept of sensorweb for Earth observations is appealing in many aspects. For instance, by increasing the spatial and temporal coverage of observations from space and other vantage points, one can eventually aid in increasing the accuracy of the atmospheric models which are precursor to hurricane track prediction, volcanic eruption forecast, and trajectory path of transcontinental transport of dust, harmful nuclear and chemical plumes. In reality, there is little analysis available in terms of benefits, costs and optimized set of sensors needed to make these necessary observations. This is a complex problem that must be carefully studied and balanced over many boundaries such as science, defense, early warning, security, and surveillance. Simplistically, the sensorweb concept from the technological point of view alone has a great appeal in the defense, early warning and security applications. In fact, it can be relatively less expensive in per unit cost as opposed to building and deploying it for the scientific use. However, overall observing approach should not be singled out and aligned somewhat orthogonally to serve a particular need. On the other hand, the sensorweb should be designed and deployed to serve multiple subject areas and customers simultaneously; and can behave as directed measuring systems for both science and operational entities. Sensorweb can be designed to act as expert systems, and/or also provide a dedicated integrated surveillance network. Today, there is no system in the world that is fully integrated in terms of reporting timely multiple hazards warnings, computing the loss of life and property damage estimates, and is also designed to cater to everyone s needs. It is not an easier problem to undertake and more so is not practically solvable. At this time due to some recent events in the world, the scientific community, social scientists, and operational agencies are more cognizant and getting

  16. The Lag Model Applied to High Speed Flows

    NASA Technical Reports Server (NTRS)

    Olsen, Michael E.; Coakley, Thomas J.; Lillard, Randolph P.

    2005-01-01

    The Lag model has shown great promise in prediction of low speed and transonic separations. The predictions of the model, along with other models (Spalart-Allmaras and Menter SST) are assessed for various high speed flowfields. In addition to skin friction and separation predictions, the prediction of heat transfer are compared among these models, and some fundamental building block flowfields, are investigated.

  17. Advancing Space Weather Modeling Capabilities at the CCMC

    NASA Astrophysics Data System (ADS)

    Mays, M. Leila; Kuznetsova, Maria; Boblitt, Justin; Chulaki, Anna; MacNeice, Peter; Mendoza, Michelle; Mullinix, Richard; Pembroke, Asher; Pulkkinen, Antti; Rastaetter, Lutz; Shim, Ja Soon; Taktakishvili, Aleksandre; Wiegand, Chiu; Zheng, Yihua

    2016-04-01

    The Community Coordinated Modeling Center (CCMC, http://ccmc.gsfc.nasa.gov) serves as a community access point to an expanding collection of state-of-the-art space environment models and as a hub for collaborative development on next generation of space weather forecasting systems. In partnership with model developers and the international research and operational communities, the CCMC integrates new data streams and models from diverse sources into end-to-end space weather predictive systems, identifies weak links in data-model & model-model coupling and leads community efforts to fill those gaps. The presentation will focus on the latest model installations at the CCMC and advances in CCMC-led community-wide model validation projects.

  18. Existing Soil Carbon Models Do Not Apply to Forested Wetlands.

    SciTech Connect

    Trettin, C C; Song, B; Jurgensen, M F; Li, C

    2001-09-14

    Evaluation of 12 widely used soil carbon models to determine applicability to wetland ecosystems. For any land area that includes wetlands, none of the individual models would produce reasonable simulations based on soil processes. Study presents a wetland soil carbon model framework based on desired attributes, the DNDC model and components of the CENTURY and WMEM models. Proposed synthesis would be appropriate when considering soil carbon dynamics at multiple spatial scales and where the land area considered includes both wetland and upland ecosystems.

  19. Advanced Constitutive Modeling of Plain and Reinforced Concretes

    DTIC Science & Technology

    1988-12-31

    plastic models. Plain concrete, on the other hand. is one of the most complex structural materials in current use and, despite numerous efforts in...influence of basic material and geometric properties on damage accumulation and failure conditions. Under Tasks 1 and 2. a new, advanced model of...purpose of this study was to ascertain the influence of fundamental material , interface, and 4 0Ill l lll l * geometric properties on the nonlinear

  20. The AFDM (advanced fluid dynamics model) program: Scope and significance

    SciTech Connect

    Bohl, W.R.; Parker, F.R. ); Wilhelm, D. . Inst. fuer Neutronenphysik und Reaktortechnik); Berthier, J. )

    1990-01-01

    The origins and goals of the advanced fluid dynamics model (AFDM) program are described, and the models, algorithm, and coding used in the resulting AFDM computer program are summarized. A sample fuel-steel boiling pool calculation is presented and compared with a similar SIMMER-II calculation. A subjective assessment of the AFDM developments is given, and areas where future work is possible are detailed. 10 refs.

  1. Specification of advanced safety modeling requirements (Rev. 0).

    SciTech Connect

    Fanning, T. H.; Tautges, T. J.

    2008-06-30

    The U.S. Department of Energy's Global Nuclear Energy Partnership has lead to renewed interest in liquid-metal-cooled fast reactors for the purpose of closing the nuclear fuel cycle and making more efficient use of future repository capacity. However, the U.S. has not designed or constructed a fast reactor in nearly 30 years. Accurate, high-fidelity, whole-plant dynamics safety simulations will play a crucial role by providing confidence that component and system designs will satisfy established design limits and safety margins under a wide variety of operational, design basis, and beyond design basis transient conditions. Current modeling capabilities for fast reactor safety analyses have resulted from several hundred person-years of code development effort supported by experimental validation. The broad spectrum of mechanistic and phenomenological models that have been developed represent an enormous amount of institutional knowledge that needs to be maintained. Complicating this, the existing code architectures for safety modeling evolved from programming practices of the 1970s. This has lead to monolithic applications with interdependent data models which require significant knowledge of the complexities of the entire code in order for each component to be maintained. In order to develop an advanced fast reactor safety modeling capability, the limitations of the existing code architecture must be overcome while preserving the capabilities that already exist. To accomplish this, a set of advanced safety modeling requirements is defined, based on modern programming practices, that focuses on modular development within a flexible coupling framework. An approach for integrating the existing capabilities of the SAS4A/SASSYS-1 fast reactor safety analysis code into the SHARP framework is provided in order to preserve existing capabilities while providing a smooth transition to advanced modeling capabilities. In doing this, the advanced fast reactor safety models will

  2. Robust Decision-making Applied to Model Selection

    SciTech Connect

    Hemez, Francois M.

    2012-08-06

    The scientific and engineering communities are relying more and more on numerical models to simulate ever-increasingly complex phenomena. Selecting a model, from among a family of models that meets the simulation requirements, presents a challenge to modern-day analysts. To address this concern, a framework is adopted anchored in info-gap decision theory. The framework proposes to select models by examining the trade-offs between prediction accuracy and sensitivity to epistemic uncertainty. The framework is demonstrated on two structural engineering applications by asking the following question: Which model, of several numerical models, approximates the behavior of a structure when parameters that define each of those models are unknown? One observation is that models that are nominally more accurate are not necessarily more robust, and their accuracy can deteriorate greatly depending upon the assumptions made. It is posited that, as reliance on numerical models increases, establishing robustness will become as important as demonstrating accuracy.

  3. Applied research on extension element model in hydraulic system

    NASA Astrophysics Data System (ADS)

    Tian, Junying; Wei, Bingyang; Han, Jianhai

    2010-08-01

    This paper further researches the application of extension element model of hydraulic system. A extension element model of hydraulic system contains three parts: the prototype of a hydraulic component, the matter-element and relationelement model of hydraulic components, and the matter-element and relation-element model of hydraulic systems. The foundation building a extension element model of hydraulic system is to build its database of the prototypes of a hydraulic component. The matter-element and relation-element model of hydraulic components is a model for physical hydraulic components. The the matter-element and relation-element models of hydraulic components on a hydraulic system can describe the internal links among hydraulic components. Through analysis of the connections among the matter-element and relation-element models of hydraulic components, rings, power bond graphs, and dynamic equations will be found and gained. Thus, the performance and digital simulation for a hydraulic system will be realized and finished.

  4. Developing and Applying Heterogeneous Phylogenetic Models with XRate

    PubMed Central

    Westesson, Oscar; Holmes, Ian

    2012-01-01

    Modeling sequence evolution on phylogenetic trees is a useful technique in computational biology. Especially powerful are models which take account of the heterogeneous nature of sequence evolution according to the “grammar” of the encoded gene features. However, beyond a modest level of model complexity, manual coding of models becomes prohibitively labor-intensive. We demonstrate, via a set of case studies, the new built-in model-prototyping capabilities of XRate (macros and Scheme extensions). These features allow rapid implementation of phylogenetic models which would have previously been far more labor-intensive. XRate 's new capabilities for lineage-specific models, ancestral sequence reconstruction, and improved annotation output are also discussed. XRate 's flexible model-specification capabilities and computational efficiency make it well-suited to developing and prototyping phylogenetic grammar models. XRate is available as part of the DART software package: http://biowiki.org/DART. PMID:22693624

  5. The monocular visual imaging technology model applied in the airport surface surveillance

    NASA Astrophysics Data System (ADS)

    Qin, Zhe; Wang, Jian; Huang, Chao

    2013-08-01

    At present, the civil aviation airports use the surface surveillance radar monitoring and positioning systems to monitor the aircrafts, vehicles and the other moving objects. Surface surveillance radars can cover most of the airport scenes, but because of the terminals, covered bridges and other buildings geometry, surface surveillance radar systems inevitably have some small segment blind spots. This paper presents a monocular vision imaging technology model for airport surface surveillance, achieving the perception of scenes of moving objects such as aircrafts, vehicles and personnel location. This new model provides an important complement for airport surface surveillance, which is different from the traditional surface surveillance radar techniques. Such technique not only provides clear objects activities screen for the ATC, but also provides image recognition and positioning of moving targets in this area. Thereby it can improve the work efficiency of the airport operations and avoid the conflict between the aircrafts and vehicles. This paper first introduces the monocular visual imaging technology model applied in the airport surface surveillance and then the monocular vision measurement accuracy analysis of the model. The monocular visual imaging technology model is simple, low cost, and highly efficient. It is an advanced monitoring technique which can make up blind spot area of the surface surveillance radar monitoring and positioning systems.

  6. Model predictive control based on reduced order models applied to belt conveyor system.

    PubMed

    Chen, Wei; Li, Xin

    2016-11-01

    In the paper, a model predictive controller based on reduced order model is proposed to control belt conveyor system, which is an electro-mechanics complex system with long visco-elastic body. Firstly, in order to design low-degree controller, the balanced truncation method is used for belt conveyor model reduction. Secondly, MPC algorithm based on reduced order model for belt conveyor system is presented. Because of the error bound between the full-order model and reduced order model, two Kalman state estimators are applied in the control scheme to achieve better system performance. Finally, the simulation experiments are shown that balanced truncation method can significantly reduce the model order with high-accuracy and model predictive control based on reduced-model performs well in controlling the belt conveyor system.

  7. Test model designs for advanced refractory ceramic materials

    NASA Technical Reports Server (NTRS)

    Tran, Huy Kim

    1993-01-01

    The next generation of space vehicles will be subjected to severe aerothermal loads and will require an improved thermal protection system (TPS) and other advanced vehicle components. In order to ensure the satisfactory performance system (TPS) and other advanced vehicle materials and components, testing is to be performed in environments similar to space flight. The design and fabrication of the test models should be fairly simple but still accomplish test objectives. In the Advanced Refractory Ceramic Materials test series, the models and model holders will need to withstand the required heat fluxes of 340 to 817 W/sq cm or surface temperatures in the range of 2700 K to 3000 K. The model holders should provide one dimensional (1-D) heat transfer to the samples and the appropriate flow field without compromising the primary test objectives. The optical properties such as the effective emissivity, catalytic efficiency coefficients, thermal properties, and mass loss measurements are also taken into consideration in the design process. Therefore, it is the intent of this paper to demonstrate the design schemes for different models and model holders that would accommodate these test requirements and ensure the safe operation in a typical arc jet facility.

  8. Model-free adaptive control of advanced power plants

    DOEpatents

    Cheng, George Shu-Xing; Mulkey, Steven L.; Wang, Qiang

    2015-08-18

    A novel 3-Input-3-Output (3.times.3) Model-Free Adaptive (MFA) controller with a set of artificial neural networks as part of the controller is introduced. A 3.times.3 MFA control system using the inventive 3.times.3 MFA controller is described to control key process variables including Power, Steam Throttle Pressure, and Steam Temperature of boiler-turbine-generator (BTG) units in conventional and advanced power plants. Those advanced power plants may comprise Once-Through Supercritical (OTSC) Boilers, Circulating Fluidized-Bed (CFB) Boilers, and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.

  9. Evaluation of reliability modeling tools for advanced fault tolerant systems

    NASA Technical Reports Server (NTRS)

    Baker, Robert; Scheper, Charlotte

    1986-01-01

    The Computer Aided Reliability Estimation (CARE III) and Automated Reliability Interactice Estimation System (ARIES 82) reliability tools for application to advanced fault tolerance aerospace systems were evaluated. To determine reliability modeling requirements, the evaluation focused on the Draper Laboratories' Advanced Information Processing System (AIPS) architecture as an example architecture for fault tolerance aerospace systems. Advantages and limitations were identified for each reliability evaluation tool. The CARE III program was designed primarily for analyzing ultrareliable flight control systems. The ARIES 82 program's primary use was to support university research and teaching. Both CARE III and ARIES 82 were not suited for determining the reliability of complex nodal networks of the type used to interconnect processing sites in the AIPS architecture. It was concluded that ARIES was not suitable for modeling advanced fault tolerant systems. It was further concluded that subject to some limitations (the difficulty in modeling systems with unpowered spare modules, systems where equipment maintenance must be considered, systems where failure depends on the sequence in which faults occurred, and systems where multiple faults greater than a double near coincident faults must be considered), CARE III is best suited for evaluating the reliability of advanced tolerant systems for air transport.

  10. Applying the Job Characteristics Model to the College Education Experience

    ERIC Educational Resources Information Center

    Kass, Steven J.; Vodanovich, Stephen J.; Khosravi, Jasmine Y.

    2011-01-01

    Boredom is one of the most common complaints among university students, with studies suggesting its link to poor grades, drop out, and behavioral problems. Principles borrowed from industrial-organizational psychology may help prevent boredom and enrich the classroom experience. In the current study, we applied the core dimensions of the job…

  11. Ontological Relations and the Capability Maturity Model Applied in Academia

    ERIC Educational Resources Information Center

    de Oliveira, Jerônimo Moreira; Campoy, Laura Gómez; Vilarino, Lilian

    2015-01-01

    This work presents a new approach to the discovery, identification and connection of ontological elements within the domain of characterization in learning organizations. In particular, the study can be applied to contexts where organizations require planning, logic, balance, and cognition in knowledge creation scenarios, which is the case for the…

  12. Technological Diffusion within Educational Institutions: Applying the Technology Acceptance Model.

    ERIC Educational Resources Information Center

    Wolski, Stacy; Jackson, Sally

    Expectancy models of behavior such as the Theory of Reasoned Action (TRA) and the Technology Acceptance Model (TAM) offer guidelines that aid efforts to facilitate use of new technology. These models remind us that both acceptance of and resistance to technology use are grounded in beliefs and norms regarding the technology. Although TAM is widely…

  13. Applying Meta-Analysis to Structural Equation Modeling

    ERIC Educational Resources Information Center

    Hedges, Larry V.

    2016-01-01

    Structural equation models play an important role in the social sciences. Consequently, there is an increasing use of meta-analytic methods to combine evidence from studies that estimate the parameters of structural equation models. Two approaches are used to combine evidence from structural equation models: A direct approach that combines…

  14. Applying Meta-Analysis to Structural Equation Modeling

    ERIC Educational Resources Information Center

    Hedges, Larry V.

    2016-01-01

    Structural equation models play an important role in the social sciences. Consequently, there is an increasing use of meta-analytic methods to combine evidence from studies that estimate the parameters of structural equation models. Two approaches are used to combine evidence from structural equation models: A direct approach that combines…

  15. Gasification CFD Modeling for Advanced Power Plant Simulations

    SciTech Connect

    Zitney, S.E.; Guenther, C.P.

    2005-09-01

    In this paper we have described recent progress on developing CFD models for two commercial-scale gasifiers, including a two-stage, coal slurry-fed, oxygen-blown, pressurized, entrained-flow gasifier and a scaled-up design of the PSDF transport gasifier. Also highlighted was NETL’s Advanced Process Engineering Co-Simulator for coupling high-fidelity equipment models with process simulation for the design, analysis, and optimization of advanced power plants. Using APECS, we have coupled the entrained-flow gasifier CFD model into a coal-fired, gasification-based FutureGen power and hydrogen production plant. The results for the FutureGen co-simulation illustrate how the APECS technology can help engineers better understand and optimize gasifier fluid dynamics and related phenomena that impact overall power plant performance.

  16. Advancements in Distributed Generation Issues: Interconnection, Modeling, and Tariffs

    SciTech Connect

    Thomas, H.; Kroposki, B.; Basso, T.; Treanton, B. G.

    2007-01-01

    The California Energy Commission is cost-sharing research with the Department of Energy through the National Renewable Energy Laboratory to address distributed energy resources (DER) topics. These efforts include developing interconnection and power management technologies, modeling the impacts of interconnecting DER with an area electric power system, and evaluating possible modifications to rate policies and tariffs. As a result, a DER interconnection device has been developed and tested. A workshop reviewed the status and issues of advanced power electronic devices. Software simulations used validated models of distribution circuits that incorporated DER, and tests and measurements of actual circuits with and without DER systems are being conducted to validate these models. Current policies affecting DER were reviewed and rate making policies to support deployment of DER through public utility rates and policies were identified. These advancements are expected to support the continued and expanded use of DER systems.

  17. Measurement and modeling of advanced coal conversion processes

    SciTech Connect

    Solomon, P.R.; Serio, M.A.; Hamblen, D.G. ); Smoot, L.D.; Brewster, B.S. )

    1991-09-25

    The objectives of this study are to establish the mechanisms and rates of basic steps in coal conversion processes, to integrate and incorporate this information into comprehensive computer models for coal conversion processes, to evaluate these models and to apply them to gasification, mild gasification and combustion in heat engines. (VC)

  18. Applying technical cost modeling to the metals industry

    NASA Astrophysics Data System (ADS)

    Bhatkal, Ravi; Busch, John

    1998-04-01

    Technical cost modeling is a methodology that breaks cost down into its constituent elements and estimates these elements based on sound, validated principles. In any new technology deployment where cost is an important maxim of business success—generally, all situations—cost modeling can and should be part of the process. This article discusses the application of technical cost modeling to the demands of business development in metals processing.

  19. Sensor Management for Applied Research Technologies (SMART)-On Demand Modeling (ODM) Project

    NASA Technical Reports Server (NTRS)

    Goodman, M.; Blakeslee, R.; Hood, R.; Jedlovec, G.; Botts, M.; Li, X.

    2006-01-01

    NASA requires timely on-demand data and analysis capabilities to enable practical benefits of Earth science observations. However, a significant challenge exists in accessing and integrating data from multiple sensors or platforms to address Earth science problems because of the large data volumes, varying sensor scan characteristics, unique orbital coverage, and the steep learning curve associated with each sensor and data type. The development of sensor web capabilities to autonomously process these data streams (whether real-time or archived) provides an opportunity to overcome these obstacles and facilitate the integration and synthesis of Earth science data and weather model output. A three year project, entitled Sensor Management for Applied Research Technologies (SMART) - On Demand Modeling (ODM), will develop and demonstrate the readiness of Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) capabilities that integrate both Earth observations and forecast model output into new data acquisition and assimilation strategies. The advancement of SWE-enabled systems (i.e., use of SensorML, sensor planning services - SPS, sensor observation services - SOS, sensor alert services - SAS and common observation model protocols) will have practical and efficient uses in the Earth science community for enhanced data set generation, real-time data assimilation with operational applications, and for autonomous sensor tasking for unique data collection.

  20. Sensor Management for Applied Research Technologies (SMART) On Demand Modeling (ODM) Project

    NASA Astrophysics Data System (ADS)

    Goodman, M.; Blakeslee, R.; Hood, R.; Jedlovec, G.; Botts, M.; Li, X.

    2006-12-01

    NASA requires timely on-demand data and analysis capabilities to enable practical benefits of Earth science observations. However, a significant challenge exists in accessing and integrating data from multiple sensors or platforms to address Earth science problems because of the large data volumes, varying sensor scan characteristics, unique orbital coverage, and the steep "learning curve" associated with each sensor and data type. The development of sensor web capabilities to autonomously process these data streams (whether real- time or archived) provides an opportunity to overcome these obstacles and facilitate the integration and synthesis of Earth science data and weather model output. A three year project, entitled Sensor Management for Applied Research Technologies (SMART) On Demand Modeling (ODM), will develop and demonstrate the readiness of Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) capabilities that integrate both Earth observations and forecast model output into new data acquisition and assimilation strategies. The advancement of SWE-enabled systems (i.e., use of SensorML, sensor planning services - SPS, sensor observation services - SOS, sensor alert services - SAS and common observation model protocols) will have practical and efficient uses in the Earth science community for enhanced data set generation, real-time data assimilation with operational applications, and for autonomous sensor tasking for unique data collection.

  1. Sensor Management for Applied Research Technologies (SMART)-On Demand Modeling (ODM) Project

    NASA Technical Reports Server (NTRS)

    Goodman, M.; Blakeslee, R.; Hood, R.; Jedlovec, G.; Botts, M.; Li, X.

    2006-01-01

    NASA requires timely on-demand data and analysis capabilities to enable practical benefits of Earth science observations. However, a significant challenge exists in accessing and integrating data from multiple sensors or platforms to address Earth science problems because of the large data volumes, varying sensor scan characteristics, unique orbital coverage, and the steep learning curve associated with each sensor and data type. The development of sensor web capabilities to autonomously process these data streams (whether real-time or archived) provides an opportunity to overcome these obstacles and facilitate the integration and synthesis of Earth science data and weather model output. A three year project, entitled Sensor Management for Applied Research Technologies (SMART) - On Demand Modeling (ODM), will develop and demonstrate the readiness of Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) capabilities that integrate both Earth observations and forecast model output into new data acquisition and assimilation strategies. The advancement of SWE-enabled systems (i.e., use of SensorML, sensor planning services - SPS, sensor observation services - SOS, sensor alert services - SAS and common observation model protocols) will have practical and efficient uses in the Earth science community for enhanced data set generation, real-time data assimilation with operational applications, and for autonomous sensor tasking for unique data collection.

  2. Modeling Educational Choices. A Binomial Logit Model Applied to the Demand for Higher Education.

    ERIC Educational Resources Information Center

    Jimenez, Juan de Dios; Salas-Velasco, Manual

    2000-01-01

    Presents a microeconomic analysis of the choice of university degree course (3 year or 4 year course) Spanish students make on finishing their secondary studies and applies the developed binomial logit model to survey data from 388 high school graduates. Findings show the importance of various factors in determining the likelihood of choosing the…

  3. Modeling Educational Choices. A Binomial Logit Model Applied to the Demand for Higher Education.

    ERIC Educational Resources Information Center

    Jimenez, Juan de Dios; Salas-Velasco, Manual

    2000-01-01

    Presents a microeconomic analysis of the choice of university degree course (3 year or 4 year course) Spanish students make on finishing their secondary studies and applies the developed binomial logit model to survey data from 388 high school graduates. Findings show the importance of various factors in determining the likelihood of choosing the…

  4. Transforming Collaborative Process Models into Interface Process Models by Applying an MDA Approach

    NASA Astrophysics Data System (ADS)

    Lazarte, Ivanna M.; Chiotti, Omar; Villarreal, Pablo D.

    Collaborative business models among enterprises require defining collaborative business processes. Enterprises implement B2B collaborations to execute these processes. In B2B collaborations the integration and interoperability of processes and systems of the enterprises are required to support the execution of collaborative processes. From a collaborative process model, which describes the global view of the enterprise interactions, each enterprise must define the interface process that represents the role it performs in the collaborative process in order to implement the process in a Business Process Management System. Hence, in this work we propose a method for the automatic generation of the interface process model of each enterprise from a collaborative process model. This method is based on a Model-Driven Architecture to transform collaborative process models into interface process models. By applying this method, interface processes are guaranteed to be interoperable and defined according to a collaborative process.

  5. Applying reliability models to the maintenance of Space Shuttle software

    NASA Technical Reports Server (NTRS)

    Schneidewind, Norman F.

    1992-01-01

    Software reliability models provide the software manager with a powerful tool for predicting, controlling, and assessing the reliability of software during maintenance. We show how a reliability model can be effectively employed for reliability prediction and the development of maintenance strategies using the Space Shuttle Primary Avionics Software Subsystem as an example.

  6. Hydrologic and water quality terminology as applied to modeling

    USDA-ARS?s Scientific Manuscript database

    A survey of literature and examination in particular of terminology use in a previous special collection of modeling calibration and validation papers has been conducted to arrive at a list of consistent terminology recommended for writing about hydrologic and water quality model calibration and val...

  7. Community Mobilization Model Applied to Support Grandparents Raising Grandchildren

    ERIC Educational Resources Information Center

    Miller, Jacque; Bruce, Ann; Bundy-Fazioli, Kimberly; Fruhauf, Christine A.

    2010-01-01

    This article discusses the application of a community mobilization model through a case study of one community's response to address the needs of grandparents raising grandchildren. The community mobilization model presented is one that is replicable in addressing diverse community identified issues. Discussed is the building of the partnerships,…

  8. Applying Hierarchical Model Calibration to Automatically Generated Items.

    ERIC Educational Resources Information Center

    Williamson, David M.; Johnson, Matthew S.; Sinharay, Sandip; Bejar, Isaac I.

    This study explored the application of hierarchical model calibration as a means of reducing, if not eliminating, the need for pretesting of automatically generated items from a common item model prior to operational use. Ultimately the successful development of automatic item generation (AIG) systems capable of producing items with highly similar…

  9. [Applying multilevel models in evaluation of bioequivalence (I)].

    PubMed

    Liu, Qiao-lan; Shen, Zhuo-zhi; Chen, Feng; Li, Xiao-song; Yang, Min

    2009-12-01

    This study aims to explore the application value of multilevel models for bioequivalence evaluation. Using a real example of 2 x 4 cross-over experimental design in evaluating bioequivalence of antihypertensive drug, this paper explores complex variance components corresponding to criteria statistics in existing methods recommended by FDA but obtained in multilevel models analysis. Results are compared with those from FDA standard Method of Moments, specifically on the feasibility and applicability of multilevel models in directly assessing the bioequivalence (ABE), the population bioequivalence (PBE) and the individual bioequivalence (IBE). When measuring ln (AUC), results from all variance components of the test and reference groups such as total variance (sigma(TT)(2) and sigma(TR)(2)), between-subject variance (sigma(BT)(2) and sigma(BR)(2)) and within-subject variance (sigma(WT)(2) and sigma(WR)(2)) estimated by simple 2-level models are very close to those that using the FDA Method of Moments. In practice, bioequivalence evaluation can be carried out directly by multilevel models, or by FDA criteria, based on variance components estimated from multilevel models. Both approaches produce consistent results. Multilevel models can be used to evaluate bioequivalence in cross-over test design. Compared to FDA methods, this one is more flexible in decomposing total variance into sub components in order to evaluate the ABE, PBE and IBE. Multilevel model provides a new way into the practice of bioequivalence evaluation.

  10. Model selection applied to reconstruction of the Primordial Power Spectrum

    NASA Astrophysics Data System (ADS)

    Vázquez, J. Alberto; Bridges, M.; Hobson, M. P.; Lasenby, A. N.

    2012-06-01

    The preferred shape for the primordial spectrum of curvature perturbations is determined by performing a Bayesian model selection analysis of cosmological observations. We first reconstruct the spectrum modelled as piecewise linear in log k between nodes in k-space whose amplitudes and positions are allowed to vary. The number of nodes together with their positions are chosen by the Bayesian evidence, so that we can both determine the complexity supported by the data and locate any features present in the spectrum. In addition to the node-based reconstruction, we consider a set of parameterised models for the primordial spectrum: the standard power-law parameterisation, the spectrum produced from the Lasenby & Doran (LD) model and a simple variant parameterisation. By comparing the Bayesian evidence for different classes of spectra, we find the power-law parameterisation is significantly disfavoured by current cosmological observations, which show a preference for the LD model.

  11. Modeling Outcomes: Modified Aortic Arch Advancement for Neonatal Hypoplastic Arch.

    PubMed

    Nellis, Joseph R; Chung, Timothy K; Agarwal, Nandita; Torres, Jose E; Holgren, Sarah E; Raghavan, Madhavan L; Turek, Joseph W

    Numerous surgical approaches regarding aortic arch advancement for neonatal arch hypoplasia have been described. These repairs can be classified into two categories: those that incorporate a patch and those that do not. The decision between repairs remains largely experiential, rather than empirical, because of the limited number of reported outcomes. We report early outcomes from neonates undergoing modified aortic arch advancement with an anterior patch and our experience using computational fluid dynamic modeling to better understand the hemodynamic consequences associated with this repair. A retrospective review of neonates undergoing aortic arch advancement with anterior patch in 2014 at a single institution was performed. Anatomical, perioperative, and follow-up data were collected. Three-dimensional cardiac magnetic resonance images were used to generate computational fluid dynamic models of the modified anterior patch and direct end-to-side repairs. Cardiac waveform inputs were simulated and hemodynamic analyzed. Ten neonates underwent modified aortic arch advancement. No hemodynamically significant gradients were observed at a median follow-up of 0.77 (0.30-1.2) years. Asymmetrical flow was observed in the end-to-side repair, whereas more concentric laminar flow was observed throughout the modified model. Spatial variations in velocities immediately distal to the anastomosis were greater in the end-to-side model (0.35 vs 0.17 m/s, P < 0.001). Time-averaged variations in wall shear stress during systole were greater in the end-to-side model at the same location (3.44 vs 1.98 dynes/cm, P < 0.001). Early outcomes after the use of an anterior patch for neonatal hypoplastic aortic arch repair show favorable hemodynamic outcomes.

  12. Alexandrium minutum growth controlled by phosphorus . An applied model

    NASA Astrophysics Data System (ADS)

    Chapelle, A.; Labry, C.; Sourisseau, M.; Lebreton, C.; Youenou, A.; Crassous, M. P.

    2010-11-01

    Toxic algae are a worldwide problem threatening aquaculture, public health and tourism. Alexandrium, a toxic dinoflagellate proliferates in Northwest France estuaries (i.e. the Penzé estuary) causing Paralytic Shellfish Poisoning events. Vegetative growth, and in particular the role of nutrient uptake and growth rate, are crucial parameters to understand toxic blooms. With the goal of modelling in situ Alexandrium blooms related to environmental parameters, we first try to calibrate a zero-dimensional box model of Alexandrium growth. This work focuses on phosphorus nutrition. Our objective is to calibrate Alexandrium minutum as well as Heterocapsa triquetra (a non-toxic dinoflagellate) growth under different rates of phosphorus supply, other factors being optimal and constant. Laboratory experiments are used to calibrate two growth models and three uptake models for each species. Models are then used to simulate monospecific batch and semi-continuous experiments as well as competition between the two algae (mixed cultures). Results show that the Droop growth model together with linear uptake versus quota can represent most of our observations, although a power law uptake function can more accurately simulate our phosphorus uptake data. We note that such models have limitations in non steady-state situations and cell quotas can depend on a variety of factors, so care must be taken in extrapolating these results beyond the specific conditions studied.

  13. Air modeling: Air dispersion models; regulatory applications and technological advances

    SciTech Connect

    Miller, M.; Liles, R.

    1995-09-01

    Air dispersion models are a useful and practical tool for both industry and regulatory agencies. They serve as tools for engineering, permitting, and regulations development. Their cost effectiveness and ease of implementation compared to ambient monitoring is perhaps their most-appealing trait. Based on the current momentum within the U.S. EPA to develop better models and contain regulatory burdens on industry, it is likely that air dispersion modeling will be a major player in future air regulatory initiatives.

  14. Blue sky catastrophe as applied to modeling of cardiac rhythms

    NASA Astrophysics Data System (ADS)

    Glyzin, S. D.; Kolesov, A. Yu.; Rozov, N. Kh.

    2015-07-01

    A new mathematical model for the electrical activity of the heart is proposed. The model represents a special singularly perturbed three-dimensional system of ordinary differential equations with one fast and two slow variables. A characteristic feature of the system is that its solution performs nonclassical relaxation oscillations and simultaneously undergoes a blue sky catastrophe bifurcation. Both these factors make it possible to achieve a phenomenological proximity between the time dependence of the fast component in the model and an ECG of the human heart.

  15. Testing and Implementation of Advanced Reynolds Stress Models

    NASA Technical Reports Server (NTRS)

    Speziale, Charles G.

    1997-01-01

    A research program was proposed for the testing and implementation of advanced turbulence models for non-equilibrium turbulent flows of aerodynamic importance that are of interest to NASA. Turbulence models that are being developed in connection with the Office of Naval Research ARI in Non-equilibrium are provided for implementation and testing in aerodynamic flows at NASA Langley Research Center. Close interactions were established with researchers at Nasa Langley RC and refinements to the models were made based on the results of these tests. The models that have been considered include two-equation models with an anisotropic eddy viscosity as well as full second-order closures. Three types of non-equilibrium corrections to the models have been considered in connection with the ARI on Nonequilibrium Turbulence: conducted for ONR.

  16. Processors, Pipelines, and Protocols for Advanced Modeling Networks

    NASA Technical Reports Server (NTRS)

    Coughlan, Joseph; Komar, George (Technical Monitor)

    2001-01-01

    Predictive capabilities arise from our understanding of natural processes and our ability to construct models that accurately reproduce these processes. Although our modeling state-of-the-art is primarily limited by existing computational capabilities, other technical areas will soon present obstacles to the development and deployment of future predictive capabilities. Advancement of our modeling capabilities will require not only faster processors, but new processing algorithms, high-speed data pipelines, and a common software engineering framework that allows networking of diverse models that represent the many components of Earth's climate and weather system. Development and integration of these new capabilities will pose serious challenges to the Information Systems (IS) technology community. Designers of future IS infrastructures must deal with issues that include performance, reliability, interoperability, portability of data and software, and ultimately, the full integration of various ES model systems into a unified ES modeling network.

  17. ADVANCED ELECTRIC AND MAGNETIC MATERIAL MODELS FOR FDTD ELECTROMAGNETIC CODES

    SciTech Connect

    Poole, B R; Nelson, S D; Langdon, S

    2005-05-05

    The modeling of dielectric and magnetic materials in the time domain is required for pulse power applications, pulsed induction accelerators, and advanced transmission lines. For example, most induction accelerator modules require the use of magnetic materials to provide adequate Volt-sec during the acceleration pulse. These models require hysteresis and saturation to simulate the saturation wavefront in a multipulse environment. In high voltage transmission line applications such as shock or soliton lines the dielectric is operating in a highly nonlinear regime, which require nonlinear models. Simple 1-D models are developed for fast parameterization of transmission line structures. In the case of nonlinear dielectrics, a simple analytic model describing the permittivity in terms of electric field is used in a 3-D finite difference time domain code (FDTD). In the case of magnetic materials, both rate independent and rate dependent Hodgdon magnetic material models have been implemented into 3-D FDTD codes and 1-D codes.

  18. Processors, Pipelines, and Protocols for Advanced Modeling Networks

    NASA Technical Reports Server (NTRS)

    Coughlan, Joseph; Komar, George (Technical Monitor)

    2001-01-01

    Predictive capabilities arise from our understanding of natural processes and our ability to construct models that accurately reproduce these processes. Although our modeling state-of-the-art is primarily limited by existing computational capabilities, other technical areas will soon present obstacles to the development and deployment of future predictive capabilities. Advancement of our modeling capabilities will require not only faster processors, but new processing algorithms, high-speed data pipelines, and a common software engineering framework that allows networking of diverse models that represent the many components of Earth's climate and weather system. Development and integration of these new capabilities will pose serious challenges to the Information Systems (IS) technology community. Designers of future IS infrastructures must deal with issues that include performance, reliability, interoperability, portability of data and software, and ultimately, the full integration of various ES model systems into a unified ES modeling network.

  19. Application of infinite model predictive control methodology to other advanced controllers.

    PubMed

    Abu-Ayyad, M; Dubay, R; Hernandez, J M

    2009-01-01

    This paper presents an application of most recent developed predictive control algorithm an infinite model predictive control (IMPC) to other advanced control schemes. The IMPC strategy was derived for systems with different degrees of nonlinearity on the process gain and time constant. Also, it was shown that IMPC structure uses nonlinear open-loop modeling which is conducted while closed-loop control is executed every sampling instant. The main objective of this work is to demonstrate that the methodology of IMPC can be applied to other advanced control strategies making the methodology generic. The IMPC strategy was implemented on several advanced controllers such as PI controller using Smith-Predictor, Dahlin controller, simplified predictive control (SPC), dynamic matrix control (DMC), and shifted dynamic matrix (m-DMC). Experimental work using these approaches combined with IMPC was conducted on both single-input-single-output (SISO) and multi-input-multi-output (MIMO) systems and compared with the original forms of these advanced controllers. Computer simulations were performed on nonlinear plants demonstrating that the IMPC strategy can be readily implemented on other advanced control schemes providing improved control performance. Practical work included real-time control applications on a DC motor, plastic injection molding machine and a MIMO three zone thermal system.

  20. Technical advances in studying cardiac electrophysiology - Role of rabbit models.

    PubMed

    Kang, C; Brennan, J A; Kuzmiak-Glancy, S; Garrott, K E; Kay, M W; Efimov, I R

    2016-07-01

    Cardiovascular research has made a major contribution to an unprecedented 10 year increase in life expectancy during the last 50 years: most of this increase due to a decline in mortality from heart disease and stroke. The majority of the basic cardiovascular science discoveries, which have led to this impressive extension of human life, came from investigations conducted in various small and large animal models, ranging from mouse to pig. The small animal models are currently popular because they are amenable to genetic engineering and are relatively inexpensive. The large animal models are favored at the translational stage of the investigation, as they are anatomically and physiologically more proximal to humans, and can be implanted with various devices; however, they are expensive and less amenable to genetic manipulations. With the advent of CRISPR genetic engineering technology and the advances in implantable bioelectronics, the large animal models will continue to advance. The rabbit model is particularly poised to become one of the most popular among the animal models that recapitulate human heart diseases. Here we review an array of the rabbit models of atrial and ventricular arrhythmias, as well as a range of the imaging and device technologies enabling these investigations. Copyright © 2016. Published by Elsevier Ltd.

  1. Development of the transformational advanced professional practice model.

    PubMed

    Elliott, Elizabeth C; Walden, Marlene

    2015-09-01

    The purpose of this article is to describe the development of a professional practice model (PPM) for advanced practice registered nurses (APRNs). A literature review was conducted on PPMs. Simultaneous review of authoritative resources, including The National Organization of Nurse Practitioner Faculties (NONPF) and the Licensure, Accreditation, Certification and Education (LACE) Consensus Model, was performed. An expert panel was established to validate the transformational advanced professional practice (TAPP) model. APRNs are relied upon by organizations to provide leadership in the delivery of high-quality, cost-effective health care while improving access and eliminating preventable morbidities. Existing models fail to fully capture the professional scope of practice for APRNs. The TAPP model serves as a framework to guide professional development and mentorship of APRNs in seven domains of professional practice (DOPP). To meet the Institute of Medicine's recommendations for the future of nursing, APRNs should practice to the fullest extent of their education and training. Providing clarification regarding the DOPP of the APRN role is needed to standardized professional practice. The TAPP model is an inspiring blueprint that allows APRNs to model the way by delivering comprehensive health care in seven DOPP. ©2015 American Association of Nurse Practitioners.

  2. Pressure Sensitive Paint Applied to Flexible Models Project

    NASA Technical Reports Server (NTRS)

    Schairer, Edward T.; Kushner, Laura Kathryn

    2014-01-01

    One gap in current pressure-measurement technology is a high-spatial-resolution method for accurately measuring pressures on spatially and temporally varying wind-tunnel models such as Inflatable Aerodynamic Decelerators (IADs), parachutes, and sails. Conventional pressure taps only provide sparse measurements at discrete points and are difficult to integrate with the model structure without altering structural properties. Pressure Sensitive Paint (PSP) provides pressure measurements with high spatial resolution, but its use has been limited to rigid or semi-rigid models. Extending the use of PSP from rigid surfaces to flexible surfaces would allow direct, high-spatial-resolution measurements of the unsteady surface pressure distribution. Once developed, this new capability will be combined with existing stereo photogrammetry methods to simultaneously measure the shape of a dynamically deforming model in a wind tunnel. Presented here are the results and methodology for using PSP on flexible surfaces.

  3. Applied Algebra: The Modeling Technique of Least Squares

    ERIC Educational Resources Information Center

    Zelkowski, Jeremy; Mayes, Robert

    2008-01-01

    The article focuses on engaging students in algebra through modeling real-world problems. The technique of least squares is explored, encouraging students to develop a deeper understanding of the method. (Contains 2 figures and a bibliography.)

  4. Simple queueing model applied to the city of Portland

    SciTech Connect

    Simon, P.M.; Nagel, K. |

    1998-07-31

    The authors present a simple traffic micro-simulation model that models the effects of capacity cut-off, i.e. the effect of queue built-up when demand is exceeding capacity, and queue spillback, i.e. the effect that queues can spill back across intersections when a congested link is filled up. They derive the model`s fundamental diagrams and explain it. The simulation is used to simulate traffic on the emme/2 network of the Portland (Oregon) metropolitan region (20,000 links). Demand is generated by a simplified home-to-work assignment which generates about half a million trips for the AM peak. Route assignment is done by iterative feedback between micro-simulation and router. Relaxation of the route assignment for the above problem can be achieved within about half a day of computing time on a desktop workstation.

  5. Software maturity model applied to SDI. Final report

    SciTech Connect

    Springsteen, B.

    1991-09-01

    The Strategic Defense Initiative Organization (SDIO) is undertaking initiatives to mitigate software risks and to stimulate the DoD contractor community to improve its software practices. To that end, IDA assessed the Software Engineering Institute's (SEI) software process maturity model and developed an implementation plan for its use within the SDI program. Under this plan, SDI element programs will use the SEI method to select software contractors with mature practices and to monitor contracts after they have been awarded. This document describes the SEI maturity model and the experience of contractors and government agencies. It also explains SDIO's plans to implement the model program-wide and the benefits and lessons learned from using the model on two contracts.

  6. Applying simulation and logistics modeling to tansportation issues

    SciTech Connect

    Funkhouser, B.R.; Ballweg, E.L.; Mackoy, R.D.

    1995-08-15

    This paper describes an application where transportation logistics and simulation tools are integrated to create a modeling environment for transportation planning. The Transportation Planning Model (TPM) is a tool developed for the Department of Energy (DOE) to aid in the long-term planning of their transportation resources. The focus of the tool is to aid DOE and Sandia National Laboratory analysts in the planning of future fleet sizes, driver and support personnel sizes, base site locations, and resource balancing among the base sites. The design approach is to develop a rapid modeling environment which integrates graphical user interfaces, logistics optimizing tools, and simulation modeling. Using the TPM an analyst can easily set up a shipment scenario and perform multiple ``What If`` evaluations. The TPM has been developed on personal computers using commercial off-the-shelf software tools under the WINDOW{reg_sign} operating environment.

  7. Two-Point Turbulence Closure Applied to Variable Resolution Modeling

    NASA Technical Reports Server (NTRS)

    Girimaji, Sharath S.; Rubinstein, Robert

    2011-01-01

    Variable resolution methods have become frontline CFD tools, but in order to take full advantage of this promising new technology, more formal theoretical development is desirable. Two general classes of variable resolution methods can be identified: hybrid or zonal methods in which RANS and LES models are solved in different flow regions, and bridging or seamless models which interpolate smoothly between RANS and LES. This paper considers the formulation of bridging methods using methods of two-point closure theory. The fundamental problem is to derive a subgrid two-equation model. We compare and reconcile two different approaches to this goal: the Partially Integrated Transport Model, and the Partially Averaged Navier-Stokes method.

  8. Applied topology optimization of vibro-acoustic hearing instrument models

    NASA Astrophysics Data System (ADS)

    Søndergaard, Morten Birkmose; Pedersen, Claus B. W.

    2014-02-01

    Designing hearing instruments remains an acoustic challenge as users request small designs for comfortable wear and cosmetic appeal and at the same time require sufficient amplification from the device. First, to ensure proper amplification in the device, a critical design challenge in the hearing instrument is to minimize the feedback between the outputs (generated sound and vibrations) from the receiver looping back into the microphones. Secondly, the feedback signal is minimized using time consuming trial-and-error design procedures for physical prototypes and virtual models using finite element analysis. In the present work it is demonstrated that structural topology optimization of vibro-acoustic finite element models can be used to both sufficiently minimize the feedback signal and to reduce the time consuming trial-and-error design approach. The structural topology optimization of a vibro-acoustic finite element model is shown for an industrial full scale model hearing instrument.

  9. Applied Algebra: The Modeling Technique of Least Squares

    ERIC Educational Resources Information Center

    Zelkowski, Jeremy; Mayes, Robert

    2008-01-01

    The article focuses on engaging students in algebra through modeling real-world problems. The technique of least squares is explored, encouraging students to develop a deeper understanding of the method. (Contains 2 figures and a bibliography.)

  10. Joint regression analysis and AMMI model applied to oat improvement

    NASA Astrophysics Data System (ADS)

    Oliveira, A.; Oliveira, T. A.; Mejza, S.

    2012-09-01

    In our work we present an application of some biometrical methods useful in genotype stability evaluation, namely AMMI model, Joint Regression Analysis (JRA) and multiple comparison tests. A genotype stability analysis of oat (Avena Sativa L.) grain yield was carried out using data of the Portuguese Plant Breeding Board, sample of the 22 different genotypes during the years 2002, 2003 and 2004 in six locations. In Ferreira et al. (2006) the authors state the relevance of the regression models and of the Additive Main Effects and Multiplicative Interactions (AMMI) model, to study and to estimate phenotypic stability effects. As computational techniques we use the Zigzag algorithm to estimate the regression coefficients and the agricolae-package available in R software for AMMI model analysis.

  11. Advanced computer modeling techniques expand belt conveyor technology

    SciTech Connect

    Alspaugh, M.

    1998-07-01

    Increased mining production is continuing to challenge engineers and manufacturers to keep up. The pressure to produce larger and more versatile equipment is increasing. This paper will show some recent major projects in the belt conveyor industry that have pushed the limits of design and engineering technology. Also, it will discuss the systems engineering discipline and advanced computer modeling tools that have helped make these achievements possible. Several examples of technologically advanced designs will be reviewed. However, new technology can sometimes produce increased problems with equipment availability and reliability if not carefully developed. Computer modeling techniques that help one design larger equipment can also compound operational headaches if engineering processes and algorithms are not carefully analyzed every step of the way.

  12. Applying different spatial distribution and modelling concepts in three nested mesoscale catchments of Germany

    NASA Astrophysics Data System (ADS)

    Bongartz, K.

    Distributed, physically based river basin models are receiving increasing importance in integrated water resources management (IWRM) in Germany and in Europe, especially after the release of the new European Water Framework Directive (WFD). Applications in mesoscale catchments require an appropriate approach to represent the spatial distribution of related catchment properties such as land use, soil physics and topography by utilizing techniques of remote sensing and GIS analyses. The challenge is to delineate scale independent homogeneous modelling entities which, on the one hand may represent the dynamics of the dominant hydrological processes and, on the other hand can be derived from spatially distributed physiographical catchment properties. This scaling problem is tackled in this regional modelling study by applying the concept of hydrological response units (HRUs). In a nested catchment approach three different modelling conceptualisations are used to describe the runoff processes: (i) the topographic stream-segment-based HRU delineation proposed by Leavesley et al. [Precipitation-Runoff-Modelling-System, User’s Manual, Water Resource Investigations Report 83-4238, US Geological Survey, 1983]; (ii) the process based physiographic HRU-concept introduced by Flügel [Hydrol. Process. 9 (1995) 423] and (iii) an advanced HRU-concept adapted from (ii), which included the topographic topology of HRU-areas and the river network developed by Staudenraush [Eco Regio 8 (2000) 121]. The influence of different boundary conditions associated with changing the landuse classes, the temporal data resolution and the landuse scenarios were investigated. The mesoscale catchment of the river Ilm ( A∼895 km 2) in Thuringia, Germany, and the Precipitation-Runoff-Modelling-System (PRMS) were selected for this study. Simulations show that the physiographic based concept is a reliable method for modelling basin dynamics in catchments up to 200 km 2 whereas in larger catchments

  13. 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.

  14. Advanced geothermal hydraulics model -- Phase 1 final report, Part 2

    SciTech Connect

    W. Zheng; J. Fu; W. C. Maurer

    1999-07-01

    An advanced geothermal well hydraulics model (GEODRIL) is being developed to accurately calculate bottom-hole conditions in these hot wells. In Phase 1, real-time monitoring and other improvements were added to GEODRIL. In Phase 2, GEODRIL will be integrated into Marconi's Intelligent Drilling Monitor (IDM) that will use artificial intelligence to detect lost circulation, fluid influxes and other circulation problems in geothermal wells. This software platform has potential for significantly reducing geothermal drilling costs.

  15. Applying artificial vision models to human scene understanding.

    PubMed

    Aminoff, Elissa M; Toneva, Mariya; Shrivastava, Abhinav; Chen, Xinlei; Misra, Ishan; Gupta, Abhinav; Tarr, Michael J

    2015-01-01

    How do we understand the complex patterns of neural responses that underlie scene understanding? Studies of the network of brain regions held to be scene-selective-the parahippocampal/lingual region (PPA), the retrosplenial complex (RSC), and the occipital place area (TOS)-have typically focused on single visual dimensions (e.g., size), rather than the high-dimensional feature space in which scenes are likely to be neurally represented. Here we leverage well-specified artificial vision systems to explicate a more complex understanding of how scenes are encoded in this functional network. We correlated similarity matrices within three different scene-spaces arising from: (1) BOLD activity in scene-selective brain regions; (2) behavioral measured judgments of visually-perceived scene similarity; and (3) several different computer vision models. These correlations revealed: (1) models that relied on mid- and high-level scene attributes showed the highest correlations with the patterns of neural activity within the scene-selective network; (2) NEIL and SUN-the models that best accounted for the patterns obtained from PPA and TOS-were different from the GIST model that best accounted for the pattern obtained from RSC; (3) The best performing models outperformed behaviorally-measured judgments of scene similarity in accounting for neural data. One computer vision method-NEIL ("Never-Ending-Image-Learner"), which incorporates visual features learned as statistical regularities across web-scale numbers of scenes-showed significant correlations with neural activity in all three scene-selective regions and was one of the two models best able to account for variance in the PPA and TOS. We suggest that these results are a promising first step in explicating more fine-grained models of neural scene understanding, including developing a clearer picture of the division of labor among the components of the functional scene-selective brain network.

  16. ADVISOR: a systems analysis tool for advanced vehicle modeling

    NASA Astrophysics Data System (ADS)

    Markel, T.; Brooker, A.; Hendricks, T.; Johnson, V.; Kelly, K.; Kramer, B.; O'Keefe, M.; Sprik, S.; Wipke, K.

    This paper provides an overview of Advanced Vehicle Simulator (ADVISOR)—the US Department of Energy's (DOE's) ADVISOR written in the MATLAB/Simulink environment and developed by the National Renewable Energy Laboratory. ADVISOR provides the vehicle engineering community with an easy-to-use, flexible, yet robust and supported analysis package for advanced vehicle modeling. It is primarily used to quantify the fuel economy, the performance, and the emissions of vehicles that use alternative technologies including fuel cells, batteries, electric motors, and internal combustion engines in hybrid (i.e. multiple power sources) configurations. It excels at quantifying the relative change that can be expected due to the implementation of technology compared to a baseline scenario. ADVISOR's capabilities and limitations are presented and the power source models that are included in ADVISOR are discussed. Finally, several applications of the tool are presented to highlight ADVISOR's functionality. The content of this paper is based on a presentation made at the 'Development of Advanced Battery Engineering Models' workshop held in Crystal City, Virginia in August 2001.

  17. A Model-Based Prognostics Approach Applied to Pneumatic Valves

    NASA Technical Reports Server (NTRS)

    Daigle, Matthew J.; Goebel, Kai

    2011-01-01

    Within the area of systems health management, the task of prognostics centers on predicting when components will fail. Model-based prognostics exploits domain knowledge of the system, its components, and how they fail by casting the underlying physical phenomena in a physics-based model that is derived from first principles. Uncertainty cannot be avoided in prediction, therefore, algorithms are employed that help in managing these uncertainties. The particle filtering algorithm has become a popular choice for model-based prognostics due to its wide applicability, ease of implementation, and support for uncertainty management. We develop a general model-based prognostics methodology within a robust probabilistic framework using particle filters. As a case study, we consider a pneumatic valve from the Space Shuttle cryogenic refueling system. We develop a detailed physics-based model of the pneumatic valve, and perform comprehensive simulation experiments to illustrate our prognostics approach and evaluate its effectiveness and robustness. The approach is demonstrated using historical pneumatic valve data from the refueling system.

  18. GIS-Based Population Model Applied to Nevada Transportation Routes

    SciTech Connect

    Mills, G.S.; Neuhauser, K.S.

    1999-03-04

    Recently, a model based on geographic information system (GIS) processing of US Census Block data has made high-resolution population analysis for transportation risk analysis technically and economically feasible. Population density bordering each kilometer of a route may be tabulated with specific route sections falling into each of three categories (Rural, Suburban or Urban) identified for separate risk analysis. In addition to the improvement in resolution of Urban areas along a route, the model provides a statistically-based correction to population densities in Rural and Suburban areas where Census Block dimensions may greatly exceed the 800-meter scale of interest. A semi-automated application of the GIS model to a subset of routes in Nevada (related to the Yucca Mountain project) are presented, and the results compared to previous models including a model based on published Census and other data. These comparisons demonstrate that meaningful improvement in accuracy and specificity of transportation risk analyses is dependent on correspondingly accurate and geographically-specific population density data.

  19. Intervention Models in Functional Connectivity Identification Applied to fMRI

    PubMed Central

    Takahashi, Daniel Yasumasa; Cardoso, Ellison Fernando; Martin, Maria da Graça Morais; Amaro Júnior, Edson; Morettin, Pedro Alberto

    2006-01-01

    Recent advances in neuroimaging techniques have provided precise spatial localization of brain activation applied in several neuroscience subareas. The development of functional magnetic resonance imaging (fMRI), based on the BOLD signal, is one of the most popular techniques related to the detection of neuronal activation. However, understanding the interactions between several neuronal modules is also an important task, providing a better comprehension about brain dynamics. Nevertheless, most connectivity studies in fMRI are based on a simple correlation analysis, which is only an association measure and does not provide the direction of information flow between brain areas. Other proposed methods like structural equation modeling (SEM) seem to be attractive alternatives. However, this approach assumes prior information about the causality direction and stationarity conditions, which may not be satisfied in fMRI experiments. Generally, the fMRI experiments are related to an activation task; hence, the stimulus conditions should also be included in the model. In this paper, we suggest an intervention analysis, which includes stimulus condition, allowing a nonstationary modeling. Furthermore, an illustrative application to real fMRI dataset from a simple motor task is presented. PMID:23165021

  20. The applied model of imagery use: Examination of moderation and mediation effects.

    PubMed

    Koehn, S; Stavrou, N A M; Young, J A; Morris, T

    2016-08-01

    The applied model of mental imagery use proposed an interaction effect between imagery type and imagery ability. This study had two aims: (a) the examination of imagery ability as a moderating variable between imagery type and dispositional flow, and (b) the testing of alternative mediation models. The sample consisted of 367 athletes from Scotland and Australia, who completed the Sport Imagery Questionnaire, Sport Imagery Ability Questionnaire, and Dispositional Flow Scale-2. Hierarchical regression analysis showed direct effects of imagery use and imagery ability on flow, but no significant interaction. Mediation analysis revealed a significant indirect path, indicating a partially mediated relationship (P = 0.002) between imagery use, imagery ability, and flow. Partial mediation was confirmed when the effect of cognitive imagery use and cognitive imagery ability was tested, and a full mediation model was found between motivational imagery use, motivational imagery ability, and flow. The results are discussed in conjunction with potential future research directions on advancing theory and applications. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Statistical model applied to motor evoked potentials analysis.

    PubMed

    Ma, Ying; Thakor, Nitish V; Jia, Xiaofeng

    2011-01-01

    Motor evoked potentials (MEPs) convey information regarding the functional integrity of the descending motor pathways. Absence of the MEP has been used as a neurophysiological marker to suggest cortico-spinal abnormalities in the operating room. Due to their high variability and sensitivity, detailed quantitative studies of MEPs are lacking. This paper applies a statistical method to characterize MEPs by estimating the number of motor units and single motor unit potential amplitudes. A clearly increasing trend of single motor unit potential amplitudes in the MEPs after each pulse of the stimulation pulse train is revealed by this method. This statistical method eliminates the effects of anesthesia, and provides an objective assessment of MEPs. Consequently this statistical method has high potential to be useful in future quantitative MEPs analysis.

  2. A modified Bogoliubov method applied to a simple boson model

    NASA Astrophysics Data System (ADS)

    Litt, O.; Bassichis, W. H.

    2017-01-01

    We use a non-gauge-invariant modification of the exact Hamiltonian to obtain a new Hamiltonian-like operator for a simple exactly solvable boson model. The eigenvalues of the new operator are close to those of the original Hamiltonian. We make a one-body approximation of the new two-body operator in the spirit of the Bogoliubov approximation. Because only the number operator appears, the c-number approximation is not required individually for the creation or annihilation operators in the ground state. For the simple model, the results using the new approximation are closer to the exact results than the usual Bogoliubov results over a wide range of parameters. The improvement increases dramatically as the model interaction strength increases.

  3. Radiative transfer theory applied to ocean bottom modeling.

    PubMed

    Quijano, Jorge E; Zurk, Lisa M

    2009-10-01

    Research on the propagation of acoustic waves in the ocean bottom sediment is of interest for active sonar applications such as target detection and remote sensing. The interaction of acoustic energy with the sea floor sublayers is usually modeled with techniques based on the full solution of the wave equation, which sometimes leads to mathematically intractable problems. An alternative way to model wave propagation in layered media containing random scatterers is the radiative transfer (RT) formulation, which is a well established technique in the electromagnetics community and is based on the principle of conservation of energy. In this paper, the RT equation is used to model the backscattering of acoustic energy from a layered elastic bottom sediment containing distributions of independent scatterers due to a constant single frequency excitation in the water column. It is shown that the RT formulation provides insight into the physical phenomena of scattering and conversion of energy between waves of different polarizations.

  4. Applying meta-analysis to structural equation modeling.

    PubMed

    Hedges, Larry V

    2016-06-01

    Structural equation models play an important role in the social sciences. Consequently, there is an increasing use of meta-analytic methods to combine evidence from studies that estimate the parameters of structural equation models. Two approaches are used to combine evidence from structural equation models: A direct approach that combines structural coefficients and an indirect approach that first combines correlation matrices and estimates structural coefficients from the combined correlation matrix. When there is no heterogeneity across studies, direct estimates of structural coefficients from several studies is an appealing approach. Heterogeneity of correlation matrices across studies presents both practical and conceptual problems. An alternative approach to heterogeneity is suggested as an example of how to better handle heterogeneity in this context. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  5. The OTP-model applied to the Aklim site database

    NASA Astrophysics Data System (ADS)

    Mraini, Kamilia; Jabiri, Abdelhadi; Benkhaldoun, Zouhair; Bounhir, Aziza; Hach, Youssef; Sabil, Mohammed; Habib, Abdelfettah

    2014-08-01

    Within the framework of the site prospection for the future European Extremely Large Telescope (E-ELT), a wide site characterization was achieved. Aklim site located at an altitude of 2350 m at the geographical coordinates: lat.= 30°07'38" N, long.= 8°18'31" W , in the Moroccan Middle Atlas Mountains, was one of the candidate sites chosen by the Framework Programme VI (FP6) of the European Union. To complete the fulfilled study ([19]; [21]), we have used the ModelOTP (model of optical turbulence profiles) established by [15] and improved by [6]. This model allows getting the built-in profiles of the optical turbulence under various conditions. In this paper, we present an overview of the Aklim database results, in the boundary layers and in the free atmosphere separately and we make a comparison with Cerro Pachon result [15].

  6. Biomorphodynamic modelling of inner bank advance in migrating meander bends

    NASA Astrophysics Data System (ADS)

    Zen, Simone; Zolezzi, Guido; Toffolon, Marco; Gurnell, Angela M.

    2016-07-01

    We propose a bio-morphodynamic model at bend cross-sectional scale for the lateral migration of river meander bends, where the two banks can migrate separately as a result of the mutual interaction between river flow, sediments and riparian vegetation, particularly at the interface between the permanently wet channel and the advancing floodplain. The model combines a non-linear analytical model for the morphodynamic evolution of the channel bed, a quasi-1D model to account for flow unsteadiness, and an ecological model describing riparian vegetation dynamics. Simplified closures are included to estimate the feedbacks among vegetation, hydrodynamics and sediment transport, which affect the morphology of the river-floodplain system. Model tests reveal the fundamental role of riparian plants in generating bio-morphological patterns at the advancing floodplain margin. Importantly, they provide insight into the biophysical controls of the 'bar push' mechanism and into its role in the lateral migration of meander bends and in the temporal variations of the active channel width.

  7. A kinematically driven anisotropic viscoelastic constitutive model applied to tires

    NASA Astrophysics Data System (ADS)

    Johnson, Arthur R.; Tanner, John A.; Mason, Angela J.

    1995-08-01

    Aircraft tires are composite structures manufactured with viscoelastic materials such as carbon black filled rubber and nylon cords. When loaded they experience large deflections and moderately large strains. Detailed structural models of tires require the use of either nonlinear shell or nonlinear three dimensional solid finite elements. Computational predictions of the dynamic response of tires must consider the composite viscoelastic material behavior in a realistic fashion. We describe a modification to a nonlinear anisotropic shell finite element so it can be used to model viscoelastic stresses during general deformations. The model is developed by introducing internal variables of the type used to model elastic strain energy. The internal variables are strains, curvatures, and transverse shear angles which are in a one-to-one correspondence with the generalized coordinates used to model the elastic strain energy for nonlinear response. A difference-relaxation equation is used to relate changes in the observable strain field to changes in the internal strain field. The internal stress state is introduced into the equilibrium equations by converting it to nodal loads associated with the element's displacement degrees of freedom. In this form the tangent matrix in the Newton-Raphson solution algorithm is not modified from its form for the nonlinear statics problem. Only the gradient vector is modified and the modification is not computationally costly. The existing finite element model for the Space Shuttle nose gear tire is used to provide examples of the algorithm. In the first example, the tire's rim is displaced at a constant rate up to a fixed value. In the second example, the tire's rim is enforced to follow a saw tooth load and unload curve to generate hysteresis loops.

  8. A kinematically driven anisotropic viscoelastic constitutive model applied to tires

    NASA Technical Reports Server (NTRS)

    Johnson, Arthur R.; Tanner, John A.; Mason, Angela J.

    1995-01-01

    Aircraft tires are composite structures manufactured with viscoelastic materials such as carbon black filled rubber and nylon cords. When loaded they experience large deflections and moderately large strains. Detailed structural models of tires require the use of either nonlinear shell or nonlinear three dimensional solid finite elements. Computational predictions of the dynamic response of tires must consider the composite viscoelastic material behavior in a realistic fashion. We describe a modification to a nonlinear anisotropic shell finite element so it can be used to model viscoelastic stresses during general deformations. The model is developed by introducing internal variables of the type used to model elastic strain energy. The internal variables are strains, curvatures, and transverse shear angles which are in a one-to-one correspondence with the generalized coordinates used to model the elastic strain energy for nonlinear response. A difference-relaxation equation is used to relate changes in the observable strain field to changes in the internal strain field. The internal stress state is introduced into the equilibrium equations by converting it to nodal loads associated with the element's displacement degrees of freedom. In this form the tangent matrix in the Newton-Raphson solution algorithm is not modified from its form for the nonlinear statics problem. Only the gradient vector is modified and the modification is not computationally costly. The existing finite element model for the Space Shuttle nose gear tire is used to provide examples of the algorithm. In the first example, the tire's rim is displaced at a constant rate up to a fixed value. In the second example, the tire's rim is enforced to follow a saw tooth load and unload curve to generate hysteresis loops.

  9. A kinematically driven anisotropic viscoelastic constitutive model applied to tires

    NASA Technical Reports Server (NTRS)

    Johnson, Arthur R.; Tanner, John A.; Mason, Angela J.

    1995-01-01

    Aircraft tires are composite structures manufactured with viscoelastic materials such as carbon black filled rubber and nylon cords. When loaded they experience large deflections and moderately large strains. Detailed structural models of tires require the use of either nonlinear shell or nonlinear three dimensional solid finite elements. Computational predictions of the dynamic response of tires must consider the composite viscoelastic material behavior in a realistic fashion. We describe a modification to a nonlinear anisotropic shell finite element so it can be used to model viscoelastic stresses during general deformations. The model is developed by introducing internal variables of the type used to model elastic strain energy. The internal variables are strains, curvatures, and transverse shear angles which are in a one-to-one correspondence with the generalized coordinates used to model the elastic strain energy for nonlinear response. A difference-relaxation equation is used to relate changes in the observable strain field to changes in the internal strain field. The internal stress state is introduced into the equilibrium equations by converting it to nodal loads associated with the element's displacement degrees of freedom. In this form the tangent matrix in the Newton-Raphson solution algorithm is not modified from its form for the nonlinear statics problem. Only the gradient vector is modified and the modification is not computationally costly. The existing finite element model for the Space Shuttle nose gear tire is used to provide examples of the algorithm. In the first example, the tire's rim is displaced at a constant rate up to a fixed value. In the second example, the tire's rim is enforced to follow a saw tooth load and unload curve to generate hysteresis loops.

  10. Gordon's model applied to nursing care of people with depression.

    PubMed

    Temel, M; Kutlu, F Y

    2015-12-01

    Psychiatric nurses should consider the patient's biological, psychological and social aspects. Marjory Gordon's Functional Health Pattern Model ensures a holistic approach for the patient. To examine the effectiveness of Gordon's Functional Health Pattern Model in reducing depressive symptoms, increasing self-efficacy, coping with depression and increasing hope in people with depression. A quasi-experimental two-group pre-test and post-test design was adopted. Data were collected from April 2013 to May 2014 from people with depression at the psychiatry clinic of a state hospital in Turkey; they were assigned to the intervention (n = 34) or control group (n = 34). The intervention group received nursing care according to Gordon's Functional Health Pattern Model and routine care, while the control group received routine care only. The Beck Depression Inventory, Beck Hopelessness Scale and Depression Coping Self-Efficacy Scale were used. The intervention group had significantly lower scores on the Beck Depression Inventory and Beck Hopelessness Scale at the post-test and 3-month follow-up; they had higher scores on the Depression Coping Self-Efficacy Scale at the 3-month follow-up when compared with the control group. The study was conducted at only one psychiatry clinic. The intervention and control group patients were at the clinic at the same time and influenced each other. Moreover, because clinical routines were in progress during the study, the results cannot only be attributed to nursing interventions. Nursing models offer guidance for the care provided. Practices based on the models return more efficient and systematic caregiving results with fewer health problems. Gordon's Functional Health Pattern Model was effective in improving the health of people with depression and could be introduced as routine care with ongoing evaluation in psychiatric clinics. More research is needed to evaluate Gordon's Nursing Model effect on people with depression. Future

  11. A Practical Environment to Apply Model-Driven Web Engineering

    NASA Astrophysics Data System (ADS)

    Escalona, Maria Jose; Gutiérrez, J. J.; Morero, F.; Parra, C. L.; Nieto, J.; Pérez, F.; Martín, F.; Llergo, A.

    The application of a model-driven paradigm in the development of Web Systems has yielded very good research results. Several research groups are defining metamodels, transformations, and tools which offer a suitable environment, known as model-driven Web engineering (MDWE). However, there are very few practical experiences in real Web system developments using real development teams. This chapter presents a practical environment of MDWE based on the use of NDT (navigational development techniques) and Java Web systems, and it provides a practical evaluation of its application within a real project: specialized Diraya.

  12. Combustion and flow modelling applied to the OMV VTE

    NASA Technical Reports Server (NTRS)

    Larosiliere, Louis M.; Jeng, San-Mou

    1990-01-01

    A predictive tool for hypergolic bipropellant spray combustion and flow evolution in the OMV VTE (orbital maneuvering vehicle variable thrust engine) is described. It encompasses a computational technique for the gas phase governing equations, a discrete particle method for liquid bipropellant sprays, and constitutive models for combustion chemistry, interphase exchanges, and unlike impinging liquid hypergolic stream interactions. Emphasis is placed on the phenomenological modelling of the hypergolic liquid bipropellant gasification processes. An application to the OMV VTE combustion chamber is given in order to show some of the capabilities and inadequacies of this tool.

  13. Similitude requirements and scaling relationships as applied to model testing

    NASA Technical Reports Server (NTRS)

    Wolowicz, C. H.; Brown, J. S., Jr.; Gilbert, W. P.

    1979-01-01

    The similitude requirements for the most general test conditions are presented. These similitude requirements are considered in relation to the scaling relationships, test technique, test conditions (including supersonic flow), and test objectives. Particular emphasis is placed on satisfying the various similitude requirements for incompressible and compressible flow conditions. For free flying models tests, the test velocities for incompressible flow are scaled from Froude number similitude requirements and those for compressible flow are scaled from Mach number similitude requirements. The limitations of various test techniques are indicated, with emphasis on the free flying model.

  14. Jellium-with-gap model applied to semilocal kinetic functionals

    NASA Astrophysics Data System (ADS)

    Constantin, Lucian A.; Fabiano, Eduardo; Śmiga, Szymon; Della Sala, Fabio

    2017-03-01

    We investigate a highly nonlocal generalization of the Lindhard function, given by the jellium-with-gap model. We find a band-gap-dependent gradient expansion of the kinetic energy, which performs noticeably well for large atoms. Using the static linear response theory and the simplest semilocal model for the local band gap, we derive a nonempirical generalized gradient approximation (GGA) of the kinetic energy. This GGA kinetic-energy functional is remarkably accurate for the description of weakly interacting molecular systems within the subsystem formulation of density functional theory.

  15. A sewer ventilation model applying conservation of momentum.

    PubMed

    Ward, M; Hamer, G; McDonald, A; Witherspoon, J; Loh, E; Parker, W

    2011-01-01

    The work presented herein was completed in an effort to characterize the forces influencing ventilation in gravity sewers and to develop a mathematical model, based on conservation of momentum, capable of accounting for friction at the headspace/pipe interface, drag at the air/water interface, and buoyancy caused by air density differences between a sewer headspace and ambient. Experiments were completed on two full scale sewer reaches in Australia. A carbon monoxide-based tracer technique was used to measure the ventilation rate within the sewer headspaces. Additionally, measurements of pressure, relative humidity, and temperature were measured in the ambient air and sewer headspace. The first location was a five kilometre long sewer outfall beginning at a wastewater treatment plant and terminating at the ocean. The second location was a large gravity sewer reach fitted with ventilation fans. At the first location the headspace was entirely sealed except for openings that were controlled during the experiments. In this situation forces acting on the headspace air manifested mostly as a pressure distribution within the reach, effectively eliminating friction at the pipe wall. At the second location, air was forced to move near the same velocity as the wastewater, effectively eliminating drag at the air/water interface. These experiments allowed individual terms of the momentum equation to be evaluated. Experimental results were compared to the proposed mathematical model. Conclusions regarding model accuracy are provided along with model application guidance and assumptions.

  16. An Analytical Model for Learning: An Applied Approach.

    ERIC Educational Resources Information Center

    Kassebaum, Peter Arthur

    A mediated-learning package, geared toward non-traditional students, was developed for use in the College of Marin's cultural anthropology courses. An analytical model for learning was used in the development of the package, utilizing concepts related to learning objectives, programmed instruction, Gestalt psychology, cognitive psychology, and…

  17. Existing Soil Carbon Models Do Not Apply to Forested Wetlands

    Treesearch

    Carl C. Trettin; B. Song; M.F. Jurgensen; C. Li

    2001-01-01

    When assessing the biological,geological,and chemical cycling of nutrients and elements — or when assessing carbon dynamics with respect to global change — modeling and simulation are necessary. Although wetlands occupy a relatively small proportion of Earth’s terrestrial surface (

  18. A Decision-Making Model Applied to Career Counseling.

    ERIC Educational Resources Information Center

    Olson, Christine; And Others

    1990-01-01

    A four-component model for career decision-making counseling relates each component to assessment questions and appropriate intervention strategies. The components are (1) conceptualization (definition of the problem); (2) enlargement of response repertoire (generation of alternatives); (3) identification of discriminative stimuli (consequences of…

  19. Applying the Language of Behavioral Models to Teaching Acts.

    ERIC Educational Resources Information Center

    McDonald, F. J.

    This paper illustrates how behavioral models which embody a critical language can be used to describe and predict some categories of classroom events. It defines teaching-learning as a set of events which are mediated primarily by a person, the consequence of which is change in behavior of a second person. A language for describing this phenomenon…

  20. Applying an Employee-Motivation Model to Prevent Student Plagiarism.

    ERIC Educational Resources Information Center

    Malouff, John M.; Sims, Randi L.

    1996-01-01

    A model based on Vroom's expectancy theory of employee motivation posits that instructors can prevent plagiarism by ensuring that students understand the rules of ethical writing, expect assignments to be manageable and have personal benefits, and expect plagiarism to be difficult and have important personal costs. (SK)

  1. Leadership Identity Development: Challenges in Applying a Developmental Model

    ERIC Educational Resources Information Center

    Komives, Susan R.; Longerbeam, Susan D.; Mainella, Felicia; Osteen, Laura; Owen, Julie E.; Wagner, Wendy

    2009-01-01

    The leadership identity development (LID) grounded theory (Komives, Owen, Longerbeam, Mainella, & Osteen, 2005) and related LID model (Komives, Longerbeam, Owen, Mainella, & Osteen, 2006) present a framework for understanding how individual college students develop the social identity of being collaborative, relational leaders…

  2. Applying the Integrated Developmental Model to Korean Supervisees

    ERIC Educational Resources Information Center

    Bang, Keeyeon

    2006-01-01

    This study examined the effects of the age, gender, education, and counseling experience of Korean supervisees on their self-and-other awareness, motivation, and autonomy: the three structures of the Integrated Developmental Model of supervision (Stoltenberg & Delworth, 1987). All three structures of the IDM had positive relationships with…

  3. Applying the Teacher Scholar Model in the School of Business

    ERIC Educational Resources Information Center

    Gardner, John C.; McGowan, Carl B., Jr.; Moeller, Susan E.

    2010-01-01

    The teacher-scholar model was proposed in Boyer (1990) and defines four dimensions of scholarship: 1) discovery, 2) integration, 3) application, and 4) teaching. In this paper, we describe the characteristics of scholarship, the theory of the scholarship of teaching, the excellent teacher, and undergraduate research and scholarship. We then show…

  4. Applying Transtheoretical Model to Promote Physical Activities Among Women

    PubMed Central

    Pirzadeh, Asiyeh; Mostafavi, Firoozeh; Ghofranipour, Fazllolah; Feizi, Awat

    2015-01-01

    Background: Physical activity is one of the most important indicators of health in communities but different studies conducted in the provinces of Iran showed that inactivity is prevalent, especially among women. Objectives: Inadequate regular physical activities among women, the importance of education in promoting the physical activities, and lack of studies on the women using transtheoretical model, persuaded us to conduct this study with the aim of determining the application of transtheoretical model in promoting the physical activities among women of Isfahan. Materials and Methods: This research was a quasi-experimental study which was conducted on 141 women residing in Isfahan, Iran. They were randomly divided into case and control groups. In addition to the demographic information, their physical activities and the constructs of the transtheoretical model (stages of change, processes of change, decisional balance, and self-efficacy) were measured at 3 time points; preintervention, 3 months, and 6 months after intervention. Finally, the obtained data were analyzed through t test and repeated measures ANOVA test using SPSS version 16. Results: The results showed that education based on the transtheoretical model significantly increased physical activities in 2 aspects of intensive physical activities and walking, in the case group over the time. Also, a high percentage of people have shown progress during the stages of change, the mean of the constructs of processes of change, as well as pros and cons. On the whole, a significant difference was observed over the time in the case group (P < 0.01). Conclusions: This study showed that interventions based on the transtheoretical model can promote the physical activity behavior among women. PMID:26834796

  5. Applying Transtheoretical Model to Promote Physical Activities Among Women.

    PubMed

    Pirzadeh, Asiyeh; Mostafavi, Firoozeh; Ghofranipour, Fazllolah; Feizi, Awat

    2015-12-01

    Physical activity is one of the most important indicators of health in communities but different studies conducted in the provinces of Iran showed that inactivity is prevalent, especially among women. Inadequate regular physical activities among women, the importance of education in promoting the physical activities, and lack of studies on the women using transtheoretical model, persuaded us to conduct this study with the aim of determining the application of transtheoretical model in promoting the physical activities among women of Isfahan. This research was a quasi-experimental study which was conducted on 141 women residing in Isfahan, Iran. They were randomly divided into case and control groups. In addition to the demographic information, their physical activities and the constructs of the transtheoretical model (stages of change, processes of change, decisional balance, and self-efficacy) were measured at 3 time points; preintervention, 3 months, and 6 months after intervention. Finally, the obtained data were analyzed through t test and repeated measures ANOVA test using SPSS version 16. The results showed that education based on the transtheoretical model significantly increased physical activities in 2 aspects of intensive physical activities and walking, in the case group over the time. Also, a high percentage of people have shown progress during the stages of change, the mean of the constructs of processes of change, as well as pros and cons. On the whole, a significant difference was observed over the time in the case group (P < 0.01). This study showed that interventions based on the transtheoretical model can promote the physical activity behavior among women.

  6. Advances on modelling of ITER scenarios: physics and computational challenges

    NASA Astrophysics Data System (ADS)

    Giruzzi, G.; Garcia, J.; Artaud, J. F.; Basiuk, V.; Decker, J.; Imbeaux, F.; Peysson, Y.; Schneider, M.

    2011-12-01

    Methods and tools for design and modelling of tokamak operation scenarios are discussed with particular application to ITER advanced scenarios. Simulations of hybrid and steady-state scenarios performed with the integrated tokamak modelling suite of codes CRONOS are presented. The advantages of a possible steady-state scenario based on cyclic operations, alternating phases of positive and negative loop voltage, with no magnetic flux consumption on average, are discussed. For regimes in which current alignment is an issue, a general method for scenario design is presented, based on the characteristics of the poloidal current density profile.

  7. Applying learning theories and instructional design models for effective instruction.

    PubMed

    Khalil, Mohammed K; Elkhider, Ihsan A

    2016-06-01

    Faculty members in higher education are involved in many instructional design activities without formal training in learning theories and the science of instruction. Learning theories provide the foundation for the selection of instructional strategies and allow for reliable prediction of their effectiveness. To achieve effective learning outcomes, the science of instruction and instructional design models are used to guide the development of instructional design strategies that elicit appropriate cognitive processes. Here, the major learning theories are discussed and selected examples of instructional design models are explained. The main objective of this article is to present the science of learning and instruction as theoretical evidence for the design and delivery of instructional materials. In addition, this article provides a practical framework for implementing those theories in the classroom and laboratory. Copyright © 2016 The American Physiological Society.

  8. Applying the Extended Parallel Process Model to workplace safety messages.

    PubMed

    Basil, Michael; Basil, Debra; Deshpande, Sameer; Lavack, Anne M

    2013-01-01

    The extended parallel process model (EPPM) proposes fear appeals are most effective when they combine threat and efficacy. Three studies conducted in the workplace safety context examine the use of various EPPM factors and their effects, especially multiplicative effects. Study 1 was a content analysis examining the use of EPPM factors in actual workplace safety messages. Study 2 experimentally tested these messages with 212 construction trainees. Study 3 replicated this experiment with 1,802 men across four English-speaking countries-Australia, Canada, the United Kingdom, and the United States. The results of these three studies (1) demonstrate the inconsistent use of EPPM components in real-world work safety communications, (2) support the necessity of self-efficacy for the effective use of threat, (3) show a multiplicative effect where communication effectiveness is maximized when all model components are present (severity, susceptibility, and efficacy), and (4) validate these findings with gory appeals across four English-speaking countries.

  9. Consideration of an applied model of public health program infrastructure.

    PubMed

    Lavinghouze, René; Snyder, Kimberly; Rieker, Patricia; Ottoson, Judith

    2013-01-01

    Systemic infrastructure is key to public health achievements. Individual public health program infrastructure feeds into this larger system. Although program infrastructure is rarely defined, it needs to be operationalized for effective implementation and evaluation. The Ecological Model of Infrastructure (EMI) is one approach to defining program infrastructure. The EMI consists of 5 core (Leadership, Partnerships, State Plans, Engaged Data, and Managed Resources) and 2 supporting (Strategic Understanding and Tactical Action) elements that are enveloped in a program's context. We conducted a literature search across public health programs to determine support for the EMI. Four of the core elements were consistently addressed, and the other EMI elements were intermittently addressed. The EMI provides an initial and partial model for understanding program infrastructure, but additional work is needed to identify evidence-based indicators of infrastructure elements that can be used to measure success and link infrastructure to public health outcomes, capacity, and sustainability.

  10. Consideration of an Applied Model of Public Health Program Infrastructure

    PubMed Central

    Lavinghouze, Rene; Snyder, Kimberly; Rieker, Patricia; Ottoson, Judith

    2015-01-01

    Systemic infrastructure is key to public health achievements. Individual public health program infrastructure feeds into this larger system. Although program infrastructure is rarely defined, it needs to be operationalized for effective implementation and evaluation. The Ecological Model of Infrastructure (EMI) is one approach to defining program infrastructure. The EMI consists of 5 core (Leadership, Partnerships, State Plans, Engaged Data, and Managed Resources) and 2 supporting (Strategic Understanding and Tactical Action) elements that are enveloped in a program’s context. We conducted a literature search across public health programs to determine support for the EMI. Four of the core elements were consistently addressed, and the other EMI elements were intermittently addressed. The EMI provides an initial and partial model for understanding program infrastructure, but additional work is needed to identify evidence-based indicators of infrastructure elements that can be used to measure success and link infrastructure to public health outcomes, capacity, and sustainability. PMID:23411417

  11. Modelling the Progression of Bird Migration with Conditional Autoregressive Models Applied to Ringing Data

    PubMed Central

    Ambrosini, Roberto; Borgoni, Riccardo; Rubolini, Diego; Sicurella, Beatrice; Fiedler, Wolfgang; Bairlein, Franz; Baillie, Stephen R.; Robinson, Robert A.; Clark, Jacquie A.; Spina, Fernando; Saino, Nicola

    2014-01-01

    Migration is a fundamental stage in the life history of several taxa, including birds, and is under strong selective pressure. At present, the only data that may allow for both an assessment of patterns of bird migration and for retrospective analyses of changes in migration timing are the databases of ring recoveries. We used ring recoveries of the Barn Swallow Hirundo rustica collected from 1908–2008 in Europe to model the calendar date at which a given proportion of birds is expected to have reached a given geographical area (‘progression of migration’) and to investigate the change in timing of migration over the same areas between three time periods (1908–1969, 1970–1990, 1991–2008). The analyses were conducted using binomial conditional autoregressive (CAR) mixed models. We first concentrated on data from the British Isles and then expanded the models to western Europe and north Africa. We produced maps of the progression of migration that disclosed local patterns of migration consistent with those obtained from the analyses of the movements of ringed individuals. Timing of migration estimated from our model is consistent with data on migration phenology of the Barn Swallow available in the literature, but in some cases it is later than that estimated by data collected at ringing stations, which, however, may not be representative of migration phenology over large geographical areas. The comparison of median migration date estimated over the same geographical area among time periods showed no significant advancement of spring migration over the whole of Europe, but a significant advancement of autumn migration in southern Europe. Our modelling approach can be generalized to any records of ringing date and locality of individuals including those which have not been recovered subsequently, as well as to geo-referenced databases of sightings of migratory individuals. PMID:25047331

  12. Modelling the progression of bird migration with conditional autoregressive models applied to ringing data.

    PubMed

    Ambrosini, Roberto; Borgoni, Riccardo; Rubolini, Diego; Sicurella, Beatrice; Fiedler, Wolfgang; Bairlein, Franz; Baillie, Stephen R; Robinson, Robert A; Clark, Jacquie A; Spina, Fernando; Saino, Nicola

    2014-01-01

    Migration is a fundamental stage in the life history of several taxa, including birds, and is under strong selective pressure. At present, the only data that may allow for both an assessment of patterns of bird migration and for retrospective analyses of changes in migration timing are the databases of ring recoveries. We used ring recoveries of the Barn Swallow Hirundo rustica collected from 1908-2008 in Europe to model the calendar date at which a given proportion of birds is expected to have reached a given geographical area ('progression of migration') and to investigate the change in timing of migration over the same areas between three time periods (1908-1969, 1970-1990, 1991-2008). The analyses were conducted using binomial conditional autoregressive (CAR) mixed models. We first concentrated on data from the British Isles and then expanded the models to western Europe and north Africa. We produced maps of the progression of migration that disclosed local patterns of migration consistent with those obtained from the analyses of the movements of ringed individuals. Timing of migration estimated from our model is consistent with data on migration phenology of the Barn Swallow available in the literature, but in some cases it is later than that estimated by data collected at ringing stations, which, however, may not be representative of migration phenology over large geographical areas. The comparison of median migration date estimated over the same geographical area among time periods showed no significant advancement of spring migration over the whole of Europe, but a significant advancement of autumn migration in southern Europe. Our modelling approach can be generalized to any records of ringing date and locality of individuals including those which have not been recovered subsequently, as well as to geo-referenced databases of sightings of migratory individuals.

  13. Structure Modeling and Validation applied to Source Physics Experiments (SPEs)

    NASA Astrophysics Data System (ADS)

    Larmat, C. S.; Rowe, C. A.; Patton, H. J.

    2012-12-01

    The U. S. Department of Energy's Source Physics Experiments (SPEs) comprise a series of small chemical explosions used to develop a better understanding of seismic energy generation and wave propagation for low-yield explosions. In particular, we anticipate improved understanding of the processes through which shear waves are generated by the explosion source. Three tests, 100, 1000 and 1000 kg yields respectively, were detonated in the same emplacement hole and recorded on the same networks of ground motion sensors in the granites of Climax Stock at the Nevada National Security Site. We present results for the analysis and modeling of seismic waveforms recorded close-in on five linear geophone lines extending radially from ground zero, having offsets from 100 to 2000 m and station spacing of 100 m. These records exhibit azimuthal variations of P-wave arrival times, and phase velocity, spreading and attenuation properties of high-frequency Rg waves. We construct a 1D seismic body-wave model starting from a refraction analysis of P-waves and adjusting to address time-domain and frequency-domain dispersion measurements of Rg waves between 2 and 9 Hz. The shallowest part of the structure we address using the arrival times recorded by near-field accelerometers residing within 200 m of the shot hole. We additionally perform a 2D modeling study with the Spectral Element Method (SEM) to investigate which structural features are most responsible for the observed variations, in particular anomalously weak amplitude decay in some directions of this topographically complicated locality. We find that a near-surface, thin, weathered layer of varying thickness and low wave speeds plays a major role on the observed waveforms. We anticipate performing full 3D modeling of the seismic near-field through analysis and validation of waveforms on the 5 radial receiver arrays.

  14. Applying CIPP Model for Learning-Object Management

    NASA Astrophysics Data System (ADS)

    Morgado, Erla M. Morales; Peñalvo, Francisco J. García; Martín, Carlos Muñoz; Gonzalez, Miguel Ángel Conde

    Although knowledge management process needs to receive some evaluation in order to determine their suitable functionality. There is not a clear definition about the stages where LOs need to be evaluated and the specific metrics to continuously promote their quality. This paper presents a proposal for LOs evaluation during their management for e-learning systems. To achieve this, we suggest specific steps for LOs design, implementation and evaluation into the four stages proposed by CIPP model (Context, Input, Process, Product).

  15. Applying Performance Models to Understand Data-Intensive Computing Efficiency

    DTIC Science & Technology

    2010-05-01

    data - intensive computing, cloud computing, analytical modeling, Hadoop, MapReduce , performance and efficiency 1 Introduction “ Data - intensive scalable...the writing of the output data to disk. In systems that replicate data across multiple nodes, such as the GFS [11] and HDFS [3] distributed file...evenly distributed across all participating nodes in the cluster , that nodes are homogeneous, and that each node retrieves its initial input from local

  16. Probabilistic graphic models applied to identification of diseases.

    PubMed

    Sato, Renato Cesar; Sato, Graziela Tiemy Kajita

    2015-01-01

    Decision-making is fundamental when making diagnosis or choosing treatment. The broad dissemination of computed systems and databases allows systematization of part of decisions through artificial intelligence. In this text, we present basic use of probabilistic graphic models as tools to analyze causality in health conditions. This method has been used to make diagnosis of Alzheimer´s disease, sleep apnea and heart diseases.

  17. Probabilistic graphic models applied to identification of diseases

    PubMed Central

    Sato, Renato Cesar; Sato, Graziela Tiemy Kajita

    2015-01-01

    ABSTRACT Decision-making is fundamental when making diagnosis or choosing treatment. The broad dissemination of computed systems and databases allows systematization of part of decisions through artificial intelligence. In this text, we present basic use of probabilistic graphic models as tools to analyze causality in health conditions. This method has been used to make diagnosis of Alzheimer´s disease, sleep apnea and heart diseases. PMID:26154555

  18. Modeling a Thermoelectric Generator Applied to Diesel Automotive Heat Recovery

    NASA Astrophysics Data System (ADS)

    Espinosa, N.; Lazard, M.; Aixala, L.; Scherrer, H.

    2010-09-01

    Thermoelectric generators (TEGs) are outstanding devices for automotive waste heat recovery. Their packaging, lack of moving parts, and direct heat to electrical conversion are the main benefits. Usually, TEGs are modeled with a constant hot-source temperature. However, energy in exhaust gases is limited, thus leading to a temperature decrease as heat is recovered. Therefore thermoelectric properties change along the TEG, affecting performance. A thermoelectric generator composed of Mg2Si/Zn4Sb3 for high temperatures followed by Bi2Te3 for low temperatures has been modeled using engineering equation solver (EES) software. The model uses the finite-difference method with a strip-fins convective heat transfer coefficient. It has been validated on a commercial module with well-known properties. The thermoelectric connection and the number of thermoelements have been addressed as well as the optimum proportion of high-temperature material for a given thermoelectric heat exchanger. TEG output power has been estimated for a typical commercial vehicle at 90°C coolant temperature.

  19. [Applying a cervical cancer control model in Soacha, Colombia].

    PubMed

    Wiesner-Ceballos, Carolina; Cendales-Duarte, Ricardo; Tovar-Murillo, Sandra L

    2008-01-01

    Low-income countries, like Colombia, have recorded a low impact on mortality rates due to cervical cancer. This can be partially explained by the cancer control models and their approaches implemented so far. This study adopted a cancer control model designed by the National Cancer Institute (Instituto Nacional de Cancerología) based on interventions at three different levels and on using social strategies founded on a human rights' perspective. A participatory community-based intervention was carried out in three phases: diagnosis (2004-2005), intervention (2006) and evaluation (2007). The evaluation phase included three components: analysing community leaders' perceptions of human rights, a comparative analysis of population surveys before (2005) and after the intervention (2007) and analysing the demand for cytology services (2001-2007) and analysing gaining access to definitive diagnosis and treatment (2007). A significant increase in activities related to human rights' claims was found. Cytological coverage during the last year reached 75% in the most vulnerable females. The intervention contributed towards recovering credibility in public health services. It also enhanced the quality of the services being offered to women. The cancer control model promoted the development of effective action at multiple levels. Encouraging a human rights' approach is pertinent in cancer control programmes.

  20. Mathematical model of gas plasma applied to chronic wounds

    SciTech Connect

    Wang, J. G.; Liu, X. Y.; Liu, D. W.; Lu, X. P.; Zhang, Y. T.

    2013-11-15

    Chronic wounds are a major burden for worldwide health care systems, and patients suffer pain and discomfort from this type of wound. Recently gas plasmas have been shown to safely speed chronic wounds healing. In this paper, we develop a deterministic mathematical model formulated by eight-species reaction-diffusion equations, and use it to analyze the plasma treatment process. The model follows spatial and temporal concentration within the wound of oxygen, chemoattractants, capillary sprouts, blood vessels, fibroblasts, extracellular matrix material, nitric oxide (NO), and inflammatory cell. Two effects of plasma, increasing NO concentration and reducing bacteria load, are considered in this model. The plasma treatment decreases the complete healing time from 25 days (normal wound healing) to 17 days, and the contributions of increasing NO concentration and reducing bacteria load are about 1/4 and 3/4, respectively. Increasing plasma treatment frequency from twice to three times per day accelerates healing process. Finally, the response of chronic wounds of different etiologies to treatment with gas plasmas is analyzed.

  1. Experiences & Tools from Modeling Instruction Applied to Earth Sciences

    NASA Astrophysics Data System (ADS)

    Cervenec, J.; Landis, C. E.

    2012-12-01

    The Framework for K-12 Science Education calls for stronger curricular connections within the sciences, greater depth in understanding, and tasks higher on Bloom's Taxonomy. Understanding atmospheric sciences draws on core knowledge traditionally taught in physics, chemistry, and in some cases, biology. If this core knowledge is not conceptually sound, well retained, and transferable to new settings, understanding the causes and consequences of climate changes become a task in memorizing seemingly disparate facts to a student. Fortunately, experiences and conceptual tools have been developed and refined in the nationwide network of Physics Modeling and Chemistry Modeling teachers to build necessary understanding of conservation of mass, conservation of energy, particulate nature of matter, kinetic molecular theory, and particle model of light. Context-rich experiences are first introduced for students to construct an understanding of these principles and then conceptual tools are deployed for students to resolve misconceptions and deepen their understanding. Using these experiences and conceptual tools takes an investment of instructional time, teacher training, and in some cases, re-envisioning the format of a science classroom. There are few financial barriers to implementation and students gain a greater understanding of the nature of science by going through successive cycles of investigation and refinement of their thinking. This presentation shows how these experiences and tools could be used in an Earth Science course to support students developing conceptually rich understanding of the atmosphere and connections happening within.

  2. Mathematical model of gas plasma applied to chronic wounds

    NASA Astrophysics Data System (ADS)

    Wang, J. G.; Liu, X. Y.; Liu, D. W.; Lu, X. P.; Zhang, Y. T.

    2013-11-01

    Chronic wounds are a major burden for worldwide health care systems, and patients suffer pain and discomfort from this type of wound. Recently gas plasmas have been shown to safely speed chronic wounds healing. In this paper, we develop a deterministic mathematical model formulated by eight-species reaction-diffusion equations, and use it to analyze the plasma treatment process. The model follows spatial and temporal concentration within the wound of oxygen, chemoattractants, capillary sprouts, blood vessels, fibroblasts, extracellular matrix material, nitric oxide (NO), and inflammatory cell. Two effects of plasma, increasing NO concentration and reducing bacteria load, are considered in this model. The plasma treatment decreases the complete healing time from 25 days (normal wound healing) to 17 days, and the contributions of increasing NO concentration and reducing bacteria load are about 1/4 and 3/4, respectively. Increasing plasma treatment frequency from twice to three times per day accelerates healing process. Finally, the response of chronic wounds of different etiologies to treatment with gas plasmas is analyzed.

  3. Applying Model Checking to Generate Model-Based Integration Tests from Choreography Models

    NASA Astrophysics Data System (ADS)

    Wieczorek, Sebastian; Kozyura, Vitaly; Roth, Andreas; Leuschel, Michael; Bendisposto, Jens; Plagge, Daniel; Schieferdecker, Ina

    Choreography models describe the communication protocols between services. Testing of service choreographies is an important task for the quality assurance of service-based systems as used e.g. in the context of service-oriented architectures (SOA). The formal modeling of service choreographies enables a model-based integration testing (MBIT) approach. We present MBIT methods for our service choreography modeling approach called Message Choreography Models (MCM). For the model-based testing of service choreographies, MCMs are translated into Event-B models and used as input for our test generator which uses the model checker ProB.

  4. Simple Queueing Model Applied to the City of Portland

    NASA Astrophysics Data System (ADS)

    Simon, Patrice M.; Esser, Jörg; Nagel, Kai

    We use a simple traffic micro-simulation model based on queueing dynamics as introduced by Gawron [IJMPC, 9(3):393, 1998] in order to simulate traffic in Portland/Oregon. Links have a flow capacity, that is, they do not release more vehicles per second than is possible according to their capacity. This leads to queue built-up if demand exceeds capacity. Links also have a storage capacity, which means that once a link is full, vehicles that want to enter the link need to wait. This leads to queue spill-back through the network. The model is compatible with route-plan-based approaches such as TRANSIMS, where each vehicle attempts to follow its pre-computed path. Yet, both the data requirements and the computational requirements are considerably lower than for the full TRANSIMS microsimulation. Indeed, the model uses standard emme/2 network data, and runs about eight times faster than real time with more than 100 000 vehicles simultaneously in the simulation on a single Pentium-type CPU. We derive the model's fundamental diagrams and explain it. The simulation is used to simulate traffic on the emme/2 network of the Portland (Oregon) metropolitan region (20 000 links). Demand is generated by a simplified home-to-work destination assignment which generates about half a million trips for the morning peak. Route assignment is done by iterative feedback between micro-simulation and router. An iterative solution of the route assignment for the above problem can be achieved within about half a day of computing time on a desktop workstation. We compare results with field data and with results of traditional assignment runs by the Portland Metropolitan Planning Organization. Thus, with a model such as this one, it is possible to use a dynamic, activities-based approach to transportation simulation (such as in TRANSIMS) with affordable data and hardware. This should enable systematic research about the coupling of demand generation, route assignment, and micro

  5. Measurement and modeling of advanced coal conversion processes

    SciTech Connect

    Solomon, P.R.; Serio, M.A.; Hamblen, D.G. ); Smoot, L.D.; Brewster, B.S. )

    1990-01-01

    The overall objective of this program is the development of predictive capability for the design, scale up, simulation, control and feedstock evaluation in advanced coal conversion devices. This technology is important to reduce the technical and economic risks inherent in utilizing coal, a feedstock whose variable and often unexpected behavior presents a significant challenge. This program will merge significant advances made at Advanced Fuel Research, Inc. (AFR) in measuring and quantitatively describing the mechanisms in coal conversion behavior, with technology being developed at Brigham Young University (BYU) in comprehensive computer codes for mechanistic modeling of entrained-bed gasification. Additional capabilities in predicting pollutant formation will be implemented and the technology will be expanded to fixed-bed reactors. The foundation to describe coal-specific conversion behavior is AFR's Functional Group (FG) and Devolatilization, Vaporization, and Crosslinking (DVC) models, developed under previous and on-going METC sponsored programs. These models have demonstrated the capability to describe the time dependent evolution of individual gas species, and the amount and characteristics of tar and char. The combined FG-DVC model will be integrated with BYU's comprehensive two-dimensional reactor model, PCGC-2, which is currently the most widely used reactor simulation for combustion or gasification. Success in this program will be a major step in improving in predictive capabilities for coal conversion processes including: demonstrated accuracy and reliability and a generalized first principles'' treatment of coals based on readily obtained composition data. The progress during the fifteenth quarterly of the program is presented. 56 refs., 41 figs., 5 tabs.

  6. Archaeal Diversity in Biofilm Technologies Applied to Treat Urban and Industrial Wastewater: Recent Advances and Future Prospects

    PubMed Central

    Calderón, Kadiya; González-Martínez, Alejandro; Gómez-Silván, Cinta; Osorio, Francisco; Rodelas, Belén; González-López, Jesús

    2013-01-01

    Biological wastewater treatment (WWT) frequently relies on biofilms for the removal of anthropogenic contaminants. The use of inert carrier materials to support biofilm development is often required, although under certain operating conditions microorganisms yield structures called granules, dense aggregates of self-immobilized cells with the characteristics of biofilms maintained in suspension. Molecular techniques have been successfully applied in recent years to identify the prokaryotic communities inhabiting biofilms in WWT plants. Although methanogenic Archaea are widely acknowledged as key players for the degradation of organic matter in anaerobic bioreactors, other biotechnological functions fulfilled by Archaea are less explored, and research on their significance and potential for WWT is largely needed. In addition, the occurrence of biofilms in WWT plants can sometimes be a source of operational problems. This is the case for membrane bioreactors (MBR), an advanced technology that combines conventional biological treatment with membrane filtration, which is strongly limited by biofouling, defined as the undesirable accumulation of microbial biofilms and other materials on membrane surfaces. The prevalence and spatial distribution of archaeal communities in biofilm-based WWT as well as their role in biofouling are reviewed here, in order to illustrate the significance of this prokaryotic cellular lineage in engineered environments devoted to WWT. PMID:24022691

  7. Virtual building environments (VBE) - Applying information modeling to buildings

    SciTech Connect

    Bazjanac, Vladimir

    2004-06-21

    A Virtual Building Environment (VBE) is a ''place'' where building industry project staffs can get help in creating Building Information Models (BIM) and in the use of virtual buildings. It consists of a group of industry software that is operated by industry experts who are also experts in the use of that software. The purpose of a VBE is to facilitate expert use of appropriate software applications in conjunction with each other to efficiently support multidisciplinary work. This paper defines BIM and virtual buildings, and describes VBE objectives, set-up and characteristics of operation. It informs about the VBE Initiative and the benefits from a couple of early VBE projects.

  8. Applying the Adams influence model in nurse executive practice.

    PubMed

    Adams, Jeffrey M; Erickson, Jeanette Ives

    2011-04-01

    The ability to influence others is a required competency for nurse executives trying to achieve positive patient/organizational outcomes. The Adams Influence Model (AIM) is a framework for understanding the factors, attributes, and process of influence. The AIM is grounded in nursing and organizational literature and provides nurse leaders with a road map for developing an effective strategy to achieve influence with individuals and/or groups. The authors describe the AIM and present a case study illustrating its application by a chief nurse executive.

  9. Developing a Model of Advanced Training to Promote Career Advancement for Certified Genetic Counselors: An Investigation of Expanded Skills, Advanced Training Paths, and Professional Opportunities.

    PubMed

    Baty, Bonnie J; Trepanier, Angela; Bennett, Robin L; Davis, Claire; Erby, Lori; Hippman, Catriona; Lerner, Barbara; Matthews, Anne; Myers, Melanie F; Robbins, Carol B; Singletary, Claire N

    2016-08-01

    There are currently multiple paths through which genetic counselors can acquire advanced knowledge and skills. However, outside of continuing education opportunities, there are few formal training programs designed specifically for the advanced training of genetic counselors. In the genetic counseling profession, there is currently considerable debate about the paths that should be available to attain advanced skills, as well as the skills that might be needed for practice in the future. The Association of Genetic Counseling Program Directors (AGCPD) convened a national committee, the Committee on Advanced Training for Certified Genetic Counselors (CATCGC), to investigate varied paths to post-master's training and career development. The committee began its work by developing three related grids that view career advancement from the viewpoints of the skills needed to advance (skills), ways to obtain these skills (paths), and existing genetic counselor positions that offer career change or advancement (positions). Here we describe previous work related to genetic counselor career advancement, the charge of the CATCGC, our preliminary work in developing a model through which to view genetic counselor advanced training and career advancement opportunities, and our next steps in further developing and disseminating the model.

  10. Accessing patient-centered care using the advanced access model.

    PubMed

    Tantau, Catherine

    2009-01-01

    Waits and delays for healthcare are legendary. These delays are not only frustrating and potentially hazardous for patients and providers but also represent significant cost to office practices. The traditional medical model that defines urgent care versus routine care is a vain and futile attempt to sort demand. This approach is at constant odds with patients' definition of urgency. Trusting patients to determine when and how they want to access care makes sense from a customer service perspective. If approached systematically using the principles of Advanced Access, patient demand patterns can be tracked to forecast demand. These demand patterns become the template for deploying the resources necessary to meet patients' needs. Although not a simple journey, the transformation to Advanced Access provides an entree to patient-centered care where patients can say, "I get exactly the care I want and need, when I want and need it."

  11. Elevated Temperature Testing and Modeling of Advanced Toughened Ceramic Materials

    NASA Technical Reports Server (NTRS)

    Keith, Theo G.

    2005-01-01

    The purpose of this report is to provide a final report for the period of 12/1/03 through 11/30/04 for NASA Cooperative Agreement NCC3-776, entitled "Elevated Temperature Testing and Modeling of Advanced Toughened Ceramic Materials." During this final period, major efforts were focused on both the determination of mechanical properties of advanced ceramic materials and the development of mechanical test methodologies under several different programs of the NASA-Glenn. The important research activities made during this period are: 1. Mechanical properties evaluation of two gas-turbine grade silicon nitrides. 2) Mechanical testing for fuel-cell seal materials. 3) Mechanical properties evaluation of thermal barrier coatings and CFCCs and 4) Foreign object damage (FOD) testing.

  12. Advanced Performance Modeling with Combined Passive and Active Monitoring

    SciTech Connect

    Dovrolis, Constantine; Sim, Alex

    2015-04-15

    To improve the efficiency of resource utilization and scheduling of scientific data transfers on high-speed networks, the "Advanced Performance Modeling with combined passive and active monitoring" (APM) project investigates and models a general-purpose, reusable and expandable network performance estimation framework. The predictive estimation model and the framework will be helpful in optimizing the performance and utilization of networks as well as sharing resources with predictable performance for scientific collaborations, especially in data intensive applications. Our prediction model utilizes historical network performance information from various network activity logs as well as live streaming measurements from network peering devices. Historical network performance information is used without putting extra load on the resources by active measurement collection. Performance measurements collected by active probing is used judiciously for improving the accuracy of predictions.

  13. Current themes and recent advances in modelling species occurrences

    PubMed Central

    2009-01-01

    Recent years have seen a huge expansion in the range of methods and approaches that are being used to predict species occurrences. This expansion has been accompanied by many improvements in statistical methods, including more accurate ways of comparing models, better null models, methods to cope with autocorrelation, and greater awareness of the importance of scale and prevalence. However, the field still suffers from problems with incorporating temporal variation, overfitted models and poor out-of-sample prediction, confusion between explanation and prediction, simplistic assumptions, and a focus on pattern over process. The greatest advances in recent years have come from integrative studies that have linked species occurrence models with other themes and topics in ecology, such as island biogeography, climate change, disease geography, and invasive species. PMID:20948597

  14. Neighborhood Design, Physical Activity, and Wellbeing: Applying the Walkability Model

    PubMed Central

    Zuniga-Teran, Adriana A.; Orr, Barron J.; Gimblett, Randy H.; Chalfoun, Nader V.; Guertin, David P.; Marsh, Stuart E.

    2017-01-01

    Neighborhood design affects lifestyle physical activity, and ultimately human wellbeing. There are, however, a limited number of studies that examine neighborhood design types. In this research, we examine four types of neighborhood designs: traditional development, suburban development, enclosed community, and cluster housing development, and assess their level of walkability and their effects on physical activity and wellbeing. We examine significant associations through a questionnaire (n = 486) distributed in Tucson, Arizona using the Walkability Model. Among the tested neighborhood design types, traditional development showed significant associations and the highest value for walkability, as well as for each of the two types of walking (recreation and transportation) representing physical activity. Suburban development showed significant associations and the highest mean values for mental health and wellbeing. Cluster housing showed significant associations and the highest mean value for social interactions with neighbors and for perceived safety from crime. Enclosed community did not obtain the highest means for any wellbeing benefit. The Walkability Model proved useful in identifying the walkability categories associated with physical activity and perceived crime. For example, the experience category was strongly and inversely associated with perceived crime. This study provides empirical evidence of the importance of including vegetation, particularly trees, throughout neighborhoods in order to increase physical activity and wellbeing. Likewise, the results suggest that regular maintenance is an important strategy to improve mental health and overall wellbeing in cities. PMID:28098785

  15. Applying the Health Belief Model to college students' health behavior

    PubMed Central

    Kim, Hak-Seon; Ahn, Joo

    2012-01-01

    The purpose of this research was to investigate how university students' nutrition beliefs influence their health behavioral intention. This study used an online survey engine (Qulatrics.com) to collect data from college students. Out of 253 questionnaires collected, 251 questionnaires (99.2%) were used for the statistical analysis. Confirmatory Factor Analysis (CFA) revealed that six dimensions, "Nutrition Confidence," "Susceptibility," "Severity," "Barrier," "Benefit," "Behavioral Intention to Eat Healthy Food," and "Behavioral Intention to do Physical Activity," had construct validity; Cronbach's alpha coefficient and composite reliabilities were tested for item reliability. The results validate that objective nutrition knowledge was a good predictor of college students' nutrition confidence. The results also clearly showed that two direct measures were significant predictors of behavioral intentions as hypothesized. Perceived benefit of eating healthy food and perceived barrier for eat healthy food to had significant effects on Behavioral Intentions and was a valid measurement to use to determine Behavioral Intentions. These findings can enhance the extant literature on the universal applicability of the model and serve as useful references for further investigations of the validity of the model within other health care or foodservice settings and for other health behavioral categories. PMID:23346306

  16. Ecosystem Modeling Applied to Nutrient Criteria Development in Rivers

    NASA Astrophysics Data System (ADS)

    Carleton, James N.; Park, Richard A.; Clough, Jonathan S.

    2009-09-01

    Threshold concentrations for biological impairment by nutrients are difficult to quantify in lotic systems, yet States and Tribes in the United States are charged with developing water quality criteria to protect these ecosystems from excessive enrichment. The analysis described in this article explores the use of the ecosystem model AQUATOX to investigate impairment thresholds keyed to biological indexes that can be simulated. The indexes selected for this exercise include percentage cyanobacterial biomass of sestonic algae, and benthic chlorophyll a. The calibrated model was used to analyze responses of these indexes to concurrent reductions in phosphorus, nitrogen, and suspended sediment in an enriched upper Midwestern river. Results suggest that the indexes would respond strongly to changes in phosphorus and suspended sediment, and less strongly to changes in nitrogen concentration. Using simulated concurrent reductions in all three water quality constituents, a total phosphorus concentration of 0.1 mg/l was identified as a threshold concentration, and therefore a hypothetical water quality criterion, for prevention of both excessive periphyton growth and sestonic cyanobacterial blooms. This kind of analysis is suggested as a way to evaluate multiple contrasting impacts of hypothetical nutrient and sediment reductions and to define nutrient criteria or target concentrations that balance multiple management objectives concurrently.

  17. Neighborhood Design, Physical Activity, and Wellbeing: Applying the Walkability Model.

    PubMed

    Zuniga-Teran, Adriana A; Orr, Barron J; Gimblett, Randy H; Chalfoun, Nader V; Guertin, David P; Marsh, Stuart E

    2017-01-13

    Neighborhood design affects lifestyle physical activity, and ultimately human wellbeing. There are, however, a limited number of studies that examine neighborhood design types. In this research, we examine four types of neighborhood designs: traditional development, suburban development, enclosed community, and cluster housing development, and assess their level of walkability and their effects on physical activity and wellbeing. We examine significant associations through a questionnaire (n = 486) distributed in Tucson, Arizona using the Walkability Model. Among the tested neighborhood design types, traditional development showed significant associations and the highest value for walkability, as well as for each of the two types of walking (recreation and transportation) representing physical activity. Suburban development showed significant associations and the highest mean values for mental health and wellbeing. Cluster housing showed significant associations and the highest mean value for social interactions with neighbors and for perceived safety from crime. Enclosed community did not obtain the highest means for any wellbeing benefit. The Walkability Model proved useful in identifying the walkability categories associated with physical activity and perceived crime. For example, the experience category was strongly and inversely associated with perceived crime. This study provides empirical evidence of the importance of including vegetation, particularly trees, throughout neighborhoods in order to increase physical activity and wellbeing. Likewise, the results suggest that regular maintenance is an important strategy to improve mental health and overall wellbeing in cities.

  18. Thermal Model Predictions of Advanced Stirling Radioisotope Generator Performance

    NASA Technical Reports Server (NTRS)

    Wang, Xiao-Yen J.; Fabanich, William Anthony; Schmitz, Paul C.

    2014-01-01

    This paper presents recent thermal model results of the Advanced Stirling Radioisotope Generator (ASRG). The three-dimensional (3D) ASRG thermal power model was built using the Thermal Desktop(trademark) thermal analyzer. The model was correlated with ASRG engineering unit test data and ASRG flight unit predictions from Lockheed Martin's (LM's) I-deas(trademark) TMG thermal model. The auxiliary cooling system (ACS) of the ASRG is also included in the ASRG thermal model. The ACS is designed to remove waste heat from the ASRG so that it can be used to heat spacecraft components. The performance of the ACS is reported under nominal conditions and during a Venus flyby scenario. The results for the nominal case are validated with data from Lockheed Martin. Transient thermal analysis results of ASRG for a Venus flyby with a representative trajectory are also presented. In addition, model results of an ASRG mounted on a Cassini-like spacecraft with a sunshade are presented to show a way to mitigate the high temperatures of a Venus flyby. It was predicted that the sunshade can lower the temperature of the ASRG alternator by 20 C for the representative Venus flyby trajectory. The 3D model also was modified to predict generator performance after a single Advanced Stirling Convertor failure. The geometry of the Microtherm HT insulation block on the outboard side was modified to match deformation and shrinkage observed during testing of a prototypic ASRG test fixture by LM. Test conditions and test data were used to correlate the model by adjusting the thermal conductivity of the deformed insulation to match the post-heat-dump steady state temperatures. Results for these conditions showed that the performance of the still-functioning inboard ACS was unaffected.

  19. Divorce and Child Behavior Problems: Applying Latent Change Score Models to Life Event Data.

    PubMed

    Malone, Patrick S; Lansford, Jennifer E; Castellino, Domini R; Berlin, Lisa J; Dodge, Kenneth A; Bates, John E; Pettit, Gregory S

    2004-07-01

    Effects of parents' divorce on children's adjustment have been studied extensively. This article applies new advances in trajectory modeling to the problem of disentangling the effects of divorce on children's adjustment from related factors such as the child's age at the time of divorce and the child's gender. Latent change score models were used to examine trajectories of externalizing behavior problems in relation to children's experience of their parents' divorce. Participants included 356 boys and girls whose biological parents were married at kindergarten entry. The children were assessed annually through Grade 9. Mothers reported whether they had divorced or separated in each 12-month period, and teachers reported children's externalizing behavior problems each year. Girls' externalizing behavior problem trajectories were not affected by experiencing their parents' divorce, regardless of the timing of the divorce. In contrast, boys who were in elementary school when their parents divorced showed an increase in externalizing behavior problems in the year of the divorce. This increase persisted in the years following the divorce. Boys who were in middle school when their parents divorced showed an increase in externalizing behavior problems in the year of the divorce followed by a decrease to below baseline levels in the year after the divorce. This decrease persisted in the following years.

  20. Noise levels from a model turbofan engine with simulated noise control measures applied

    NASA Technical Reports Server (NTRS)

    Hall, David G.; Woodward, Richard P.

    1993-01-01

    A study of estimated full-scale noise levels based on measured levels from the Advanced Ducted Propeller (ADP) sub-scale model is presented. Testing of this model was performed in the NASA Lewis Low Speed Anechoic Wind Tunnel at a simulated takeoff condition of Mach 0.2. Effective Perceived Noise Level (EPNL) estimates for the baseline configuration are documented, and also used as the control case in a study of the potential benefits of two categories of noise control. The effect of active noise control is evaluated by artificially removing various rotor-stator interaction tones. Passive noise control is simulated by applying a notch filter to the wind tunnel data. Cases with both techniques are included to evaluate hybrid active-passive noise control. The results for EPNL values are approximate because the original source data was limited in bandwidth and in sideline angular coverage. The main emphasis is on comparisons between the baseline and configurations with simulated noise control measures.

  1. Integrated Modeling Applied to the Terrestrial Planet Finder Mission

    NASA Technical Reports Server (NTRS)

    Kissil, Andrew; Kwack, Eug; Ho, Timothy; Dumont, Philip; Irish, Sandra; Weng, Ichung

    2006-01-01

    Toolsets work well, and are getting better (looking forward to significant capability increase shortly)Lessons-learned: problems encountered & solved (or temporarily worked-around). Currently, all computed WFE's & RB motions for thermal disturbance are within error budget. We need to account for CTE variation in PM:Taking CTE variation into account generally results in higher WFE's than assuming uniform CTE of 10 ppb/C (especially for higher Zernikes). Focus & Astigmatism are biggest contributors to WFE due to changes in PM front-to-back delta-temps. Design feasibility looks good: no major road-blocks. Keeping in mind the many idealizations made at this point in time: more detail modeling to follow.

  2. Applying Contamination Modelling to Spacecraft Propulsion Systems Designs and Operations

    NASA Technical Reports Server (NTRS)

    Chen, Philip T.; Thomson, Shaun; Woronowicz, Michael S.

    2000-01-01

    Molecular and particulate contaminants generated from the operations of a propulsion system may impinge on spacecraft critical surfaces. Plume depositions or clouds may hinder the spacecraft and instruments from performing normal operations. Firing thrusters will generate both molecular and particulate contaminants. How to minimize the contamination impact from the plume becomes very critical for a successful mission. The resulting effect from either molecular or particulate contamination of the thruster firing is very distinct. This paper will discuss the interconnection between the functions of spacecraft contamination modeling and propulsion system implementation. The paper will address an innovative contamination engineering approach implemented from the spacecraft concept design, manufacturing, integration and test (I&T), launch, to on- orbit operations. This paper will also summarize the implementation on several successful missions. Despite other contamination sources, only molecular contamination will be considered here.

  3. Electrostatic Model Applied to ISS Charged Water Droplet Experiment

    NASA Technical Reports Server (NTRS)

    Stevenson, Daan; Schaub, Hanspeter; Pettit, Donald R.

    2015-01-01

    The electrostatic force can be used to create novel relative motion between charged bodies if it can be isolated from the stronger gravitational and dissipative forces. Recently, Coulomb orbital motion was demonstrated on the International Space Station by releasing charged water droplets in the vicinity of a charged knitting needle. In this investigation, the Multi-Sphere Method, an electrostatic model developed to study active spacecraft position control by Coulomb charging, is used to simulate the complex orbital motion of the droplets. When atmospheric drag is introduced, the simulated motion closely mimics that seen in the video footage of the experiment. The electrostatic force's inverse dependency on separation distance near the center of the needle lends itself to analytic predictions of the radial motion.

  4. Integrated Modeling Applied to the Terrestrial Planet Finder Mission

    NASA Technical Reports Server (NTRS)

    Kissil, Andrew; Kwack, Eug; Ho, Timothy; Dumont, Philip; Irish, Sandra; Weng, Ichung

    2006-01-01

    Toolsets work well, and are getting better (looking forward to significant capability increase shortly)Lessons-learned: problems encountered & solved (or temporarily worked-around). Currently, all computed WFE's & RB motions for thermal disturbance are within error budget. We need to account for CTE variation in PM:Taking CTE variation into account generally results in higher WFE's than assuming uniform CTE of 10 ppb/C (especially for higher Zernikes). Focus & Astigmatism are biggest contributors to WFE due to changes in PM front-to-back delta-temps. Design feasibility looks good: no major road-blocks. Keeping in mind the many idealizations made at this point in time: more detail modeling to follow.

  5. Sensorless position estimator applied to nonlinear IPMC model

    NASA Astrophysics Data System (ADS)

    Bernat, Jakub; Kolota, Jakub

    2016-11-01

    This paper addresses the issue of estimating position for an ionic polymer metal composite (IPMC) known as electro active polymer (EAP). The key step is the construction of a sensorless mode considering only current feedback. This work takes into account nonlinearities caused by electrochemical effects in the material. Owing to the recent observer design technique, the authors obtained both Lyapunov function based estimation law as well as sliding mode observer. To accomplish the observer design, the IPMC model was identified through a series of experiments. The research comprises time domain measurements. The identification process was completed by means of geometric scaling of three test samples. In the proposed design, the estimated position accurately tracks the polymer position, which is illustrated by the experiments.

  6. [The bioethical principlism model applied in pain management].

    PubMed

    Souza, Layz Alves Ferreira; Pessoa, Ana Paula da Costa; Barbosa, Maria Alves; Pereira, Lilian Varanda

    2013-03-01

    An integrative literature review was developed with the purpose to analyze the scientific production regarding the relationships between pain and the principles of bioethics (autonomy, beneficence, nonmaleficence and justice). Controlled descriptors were used in three international data sources (LILACS, SciELO, MEDLINE), in April of 2012, totaling 14 publications categorized by pain and autonomy, pain and beneficence, pain and nonmaleficence, pain and justice. The adequate relief of pain is a human right and a moral issue directly related with the bioethical principlism standard model (beneficence, non-maleficence, autonomy and justice). However, many professionals overlook the pain of their patients, ignoring their ethical role when facing suffering. It was concluded that principlism has been neglected in the care of patients in pain, showing the need for new practices to change this setting.

  7. "Let's Move" campaign: applying the extended parallel process model.

    PubMed

    Batchelder, Alicia; Matusitz, Jonathan

    2014-01-01

    This article examines Michelle Obama's health campaign, "Let's Move," through the lens of the extended parallel process model (EPPM). "Let's Move" aims to reduce the childhood obesity epidemic in the United States. Developed by Kim Witte, EPPM rests on the premise that people's attitudes can be changed when fear is exploited as a factor of persuasion. Fear appeals work best (a) when a person feels a concern about the issue or situation, and (b) when he or she believes to have the capability of dealing with that issue or situation. Overall, the analysis found that "Let's Move" is based on past health campaigns that have been successful. An important element of the campaign is the use of fear appeals (as it is postulated by EPPM). For example, part of the campaign's strategies is to explain the severity of the diseases associated with obesity. By looking at the steps of EPPM, readers can also understand the strengths and weaknesses of "Let's Move."

  8. Levine's Conservation Model: A Framework for Advanced Gerontology Nursing Practice.

    PubMed

    Abumaria, Ibrahim Mahmoud; Hastings-Tolsma, Marie; Sakraida, Teresa J

    2015-01-01

    Growing numbers of older adults place increased demands on already burdened healthcare systems. The cost of managing chronic illnesses mandates greater emphasis on management and prevention. This article explores the adaptation of Levine's Conservation Model as a structure for providing care to the older adult by the adult-gerontology primary care nurse practitioner (AGNP). The AGNP role, designed to provide quality care to adult and older adult populations, offers the opportunity to not only manage health care of the elderly, but to also advocate, lead in collaborative care efforts, conduct advanced planning, and manage and negotiate health delivery systems. The use of nursing models can foster the design of effective interventions that promote health of the older adult, particularly in the long-term care environment. Levine's Conservation Model provides a useful structure for older adult care in the long-term care setting. As an ideal care manager, the AGNP would be well served to consider use of the model to guide advanced nursing practice. Recommendations for clinical practice, research, and health policy. © 2014 Wiley Periodicals, Inc.

  9. Nonspherical Radiation Driven Wind Models Applied to Be Stars

    NASA Astrophysics Data System (ADS)

    Arauxo, F. X.

    1990-11-01

    ABSTRACT. In this work we present a model for the structure of a radiatively driven wind in the meridional plane of a hot star. Rotation effects and simulation of viscous forces were included in the motion equations. The line radiation force is considered with the inclusion of the finite disk correction in self-consistent computations which also contain gravity darkening as well as distortion of the star by rotation. An application to a typical BlV star leads to mass-flux ratios between equator and pole of the order of 10 and mass loss rates in the range 5.l0 to Mo/yr. Our envelope models are flattened towards the equator and the wind terminal velocities in that region are rather high (1000 Km/s). However, in the region near the star the equatorial velocity field is dominated by rotation. RESUMEN. Se presenta un modelo de la estructura de un viento empujado radiativamente en el plano meridional de una estrella caliente. Se incluyeron en las ecuaciones de movimiento los efectos de rotaci6n y la simulaci6n de fuerzas viscosas. Se consider6 la fuerza de las lineas de radiaci6n incluyendo la correcci6n de disco finito en calculos autoconsistentes los cuales incluyen oscurecimiento gravitacional asi como distorsi6n de la estrella por rotaci6n. La aplicaci6n a una estrella tipica BlV lleva a cocientes de flujo de masa entre el ecuador y el polo del orden de 10 de perdida de masa en el intervalo 5.l0 a 10 Mo/ano. Nuestros modelos de envolvente estan achatados hacia el ecuador y las velocidads terminales del viento en esa regi6n son bastante altas (1000 Km/s). Sin embargo, en la regi6n cercana a la estrella el campo de velocidad ecuatorial esta dominado por la rotaci6n. Key words: STARS-BE -- STARS-WINDS

  10. Applying the welfare model to at-own-risk discharges.

    PubMed

    Krishna, Lalit Kumar Radha; Menon, Sumytra; Kanesvaran, Ravindran

    2017-08-01

    "At-own-risk discharges" or "self-discharges" evidences an irretrievable breakdown in the patient-clinician relationship when patients leave care facilities before completion of medical treatment and against medical advice. Dissolution of the therapeutic relationship terminates the physician's duty of care and professional liability with respect to care of the patient. Acquiescence of an at-own-risk discharge by the clinician is seen as respecting patient autonomy. The validity of such requests pivot on the assumptions that the patient is fully informed and competent to invoke an at-own-risk discharge and that care up to the point of the at-own-risk discharge meets prevailing clinical standards. Palliative care's use of a multidisciplinary team approach challenges both these assumptions. First by establishing multiple independent therapeutic relations between professionals in the multidisciplinary team and the patient who persists despite an at-own-risk discharge. These enduring therapeutic relationships negate the suggestion that no duty of care is owed the patient. Second, the continued employ of collusion, familial determinations, and the circumnavigation of direct patient involvement in family-centric societies compromises the patient's decision-making capacity and raises questions as to the patient's decision-making capacity and their ability to assume responsibility for the repercussions of invoking an at-own-risk discharge. With the validity of at-own-risk discharge request in question and the welfare and patient interest at stake, an alternative approach to assessing at-own-risk discharge requests are called for. The welfare model circumnavigates these concerns and preserves the patient's welfare through the employ of a multidisciplinary team guided holistic appraisal of the patient's specific situation that is informed by clinical and institutional standards and evidenced-based practice. The welfare model provides a robust decision-making framework for

  11. Advancing Cyberinfrastructure to support high resolution water resources modeling

    NASA Astrophysics Data System (ADS)

    Tarboton, D. G.; Ogden, F. L.; Jones, N.; Horsburgh, J. S.

    2012-12-01

    Addressing the problem of how the availability and quality of water resources at large scales are sensitive to climate variability, watershed alterations and management activities requires computational resources that combine data from multiple sources and support integrated modeling. Related cyberinfrastructure challenges include: 1) how can we best structure data and computer models to address this scientific problem through the use of high-performance and data-intensive computing, and 2) how can we do this in a way that discipline scientists without extensive computational and algorithmic knowledge and experience can take advantage of advances in cyberinfrastructure? This presentation will describe a new system called CI-WATER that is being developed to address these challenges and advance high resolution water resources modeling in the Western U.S. We are building on existing tools that enable collaboration to develop model and data interfaces that link integrated system models running within an HPC environment to multiple data sources. Our goal is to enhance the use of computational simulation and data-intensive modeling to better understand water resources. Addressing water resource problems in the Western U.S. requires simulation of natural and engineered systems, as well as representation of legal (water rights) and institutional constraints alongside the representation of physical processes. We are establishing data services to represent the engineered infrastructure and legal and institutional systems in a way that they can be used with high resolution multi-physics watershed modeling at high spatial resolution. These services will enable incorporation of location-specific information on water management infrastructure and systems into the assessment of regional water availability in the face of growing demands, uncertain future meteorological forcings, and existing prior-appropriations water rights. This presentation will discuss the informatics

  12. MICS-Asia II: Modeling gaseous pollutants and evaluating an advanced modeling system over East Asia

    NASA Astrophysics Data System (ADS)

    Fu, Joshua S.; Jang, Carey J.; Streets, David G.; Li, Zuopan; Kwok, Roger; Park, Rokjin; Han, Zhiwei

    An advanced modeling system with a "one-atmosphere" perspective, Models-3/Community Multi-scale Air Quality (CMAQ) modeling system, driven by MM5/NCEP reanalysis data as the meteorology, and GEOS-Chem outputs as boundary values was applied to simulate the O 3, and other gaseous pollutants (SO 2 and NO 2) evolution among other atmospheric chemicals for July 2001. Comparisons had been made with other models in the MICS-II exercise for the same period. Statistics of both monthly and daily means show that the model skill is very good in reproducing O 3 and SO 2 with small to moderate RMSE. The model species capture the day-to-day and spatial variability of the observations. The same O 3 model concentrations that overpredict most of the EANET observations in the MICS-II study may have underpredicted ones from monitoring networks in Beijing area that is not included in this paper. Vertical O 3 profiles at 4 ozonesonde sites are well predicted in July 2001. In fact, our model is among the best of those MICS-II models within the 2-km surface layer. The meteorology near surface and lower troposphere is well reproduced. Compared to SO 2 and O 3, the NO 2 gas concentrations are simulated less well, but the correlation coefficient is still significant. The choice of reanalysis meteorological fields and different boundary conditions generated by different global models may result in diverse spatial patterns exhibited by MICS-II models and ours. Our spatial distributions of O 3 shows a high concentration patch covering Beijing, a moderate to high pattern across Korea and Japan Sea, and a low but extensive pattern enclosing southern China, Taiwan, and East Sea. Extension of the pattern to southern China coincides with the existence of pollution problems in Guangdong and Taiwan, but overprediction of O 3 over the region deserves further improvement by various factors. One of them can be the grid resolution to resolve the complex orography in or close to the ocean. Another factor

  13. A model of smoldering combustion applied to flexible polyurethane foams

    NASA Technical Reports Server (NTRS)

    Ohlemiller, T. J.; Rogers, F.; Bellan, J.

    1979-01-01

    Smoldering combustion, particularly in upholstery and bedding materials, has been proven a serious life hazard. The simplest representation of this hazard situation is one-dimensional downward propagation of a smolder wave against a buoyant upflow (cocurrent smolder); the configuration treated here is identical in all respects to this except for the presence of a forced flow replacing the buoyant one. The complex degradation chemistry of the polyurethanes is here reduced to the two major overall reactions of char formation and char oxidation. The model solutions, which are in reasonable agreement with experimental results, show the smolder process to be oxygen-limited, which leads to some very simple trends. More subtle behavior aspects determine actual propagation velocity, fraction of fuel consumed, and apparent equivalence ratio (all of which are variable). The self-insulating character of the smolder wave makes it viable in a wide-ranging set of conditions if the igniting stimulus is sufficiently long. These results have significant implications regarding the problem of smolder prevention or hindrance.

  14. Applying Dispersive Changes to Lagrangian Particles in Groundwater Transport Models

    USGS Publications Warehouse

    Konikow, L.F.

    2010-01-01

    Method-of-characteristics groundwater transport models require that changes in concentrations computed within an Eulerian framework to account for dispersion be transferred to moving particles used to simulate advective transport. A new algorithm was developed to accomplish this transfer between nodal values and advecting particles more precisely and realistically compared to currently used methods. The new method scales the changes and adjustments of particle concentrations relative to limiting bounds of concentration values determined from the population of adjacent nodal values. The method precludes unrealistic undershoot or overshoot for concentrations of individual particles. In the new method, if dispersion causes cell concentrations to decrease during a time step, those particles in the cell having the highest concentration will decrease the most, and those with the lowest concentration will decrease the least. The converse is true if dispersion is causing concentrations to increase. Furthermore, if the initial concentration on a particle is outside the range of the adjacent nodal values, it will automatically be adjusted in the direction of the acceptable range of values. The new method is inherently mass conservative. ?? US Government 2010.

  15. Applying dispersive changes to Lagrangian particles in groundwater transport models

    USGS Publications Warehouse

    Konikow, Leonard F.

    2010-01-01

    Method-of-characteristics groundwater transport models require that changes in concentrations computed within an Eulerian framework to account for dispersion be transferred to moving particles used to simulate advective transport. A new algorithm was developed to accomplish this transfer between nodal values and advecting particles more precisely and realistically compared to currently used methods. The new method scales the changes and adjustments of particle concentrations relative to limiting bounds of concentration values determined from the population of adjacent nodal values. The method precludes unrealistic undershoot or overshoot for concentrations of individual particles. In the new method, if dispersion causes cell concentrations to decrease during a time step, those particles in the cell having the highest concentration will decrease the most, and those with the lowest concentration will decrease the least. The converse is true if dispersion is causing concentrations to increase. Furthermore, if the initial concentration on a particle is outside the range of the adjacent nodal values, it will automatically be adjusted in the direction of the acceptable range of values. The new method is inherently mass conservative.

  16. Applying revised gap analysis model in measuring hotel service quality.

    PubMed

    Lee, Yu-Cheng; Wang, Yu-Che; Chien, Chih-Hung; Wu, Chia-Huei; Lu, Shu-Chiung; Tsai, Sang-Bing; Dong, Weiwei

    2016-01-01

    With the number of tourists coming to Taiwan growing by 10-20 % since 2010, the number has increased due to an increasing number of foreign tourists, particularly after deregulation allowed admitting tourist groups, followed later on by foreign individual tourists, from mainland China. The purpose of this study is to propose a revised gap model to evaluate and improve service quality in Taiwanese hotel industry. Thus, service quality could be clearly measured through gap analysis, which was more effective for offering direction in developing and improving service quality. The HOLSERV instrument was used to identify and analyze service gaps from the perceptions of internal and external customers. The sample for this study included three main categories of respondents: tourists, employees, and managers. The results show that five gaps influenced tourists' evaluations of service quality. In particular, the study revealed that Gap 1 (management perceptions vs. customer expectations) and Gap 9 (service provider perceptions of management perceptions vs. service delivery) were more critical than the others in affecting perceived service quality, making service delivery the main area of improvement. This study contributes toward an evaluation of the service quality of the Taiwanese hotel industry from the perspectives of customers, service providers, and managers, which is considerably valuable for hotel managers. It was the aim of this study to explore all of these together in order to better understand the possible gaps in the hotel industry in Taiwan.

  17. Mouse models of advanced spontaneous metastasis for experimental therapeutics

    PubMed Central

    Francia, Giulio; Cruz-Munoz, William; Man, Shan; Xu, Ping; Kerbel, Robert S.

    2015-01-01

    An enduring problem in cancer research is the failure to reproduce highly encouraging preclinical therapeutic findings using transplanted or spontaneous primary tumours in mice in clinical trials of patients with advanced metastatic disease. There are several reasons for this, including the failure to model established, visceral metastatic disease. We therefore developed various models of aggressive multi-organ spontaneous metastasis after surgical resection of orthotopically transplanted human tumour xenografts. In this Opinion article we provide a personal perspective summarizing the prospect of their increased clinical relevance. This includes the reduced efficacy of certain targeted anticancer drugs, the late emergence of spontaneous brain metastases and the clinical trial results evaluating a highly effective therapeutic strategy previously tested using such models. PMID:21258397

  18. Advanced optical position sensors for magnetically suspended wind tunnel models

    NASA Technical Reports Server (NTRS)

    Lafleur, S.

    1985-01-01

    A major concern to aerodynamicists has been the corruption of wind tunnel test data by model support structures, such as stings or struts. A technique for magnetically suspending wind tunnel models was considered by Tournier and Laurenceau (1957) in order to overcome this problem. This technique is now implemented with the aid of a Large Magnetic Suspension and Balance System (LMSBS) and advanced position sensors for measuring model attitude and position within the test section. Two different optical position sensors are discussed, taking into account a device based on the use of linear CCD arrays, and a device utilizing area CID cameras. Current techniques in image processing have been employed to develop target tracking algorithms capable of subpixel resolution for the sensors. The algorithms are discussed in detail, and some preliminary test results are reported.

  19. Business Model Evaluation for an Advanced Multimedia Service Portfolio

    NASA Astrophysics Data System (ADS)

    Pisciella, Paolo; Zoric, Josip; Gaivoronski, Alexei A.

    In this paper we analyze quantitatively a business model for the collaborative provision of an advanced mobile data service portfolio composed of three multimedia services: Video on Demand, Internet Protocol Television and User Generated Content. We provide a description of the provision system considering the relation occurring between tecnical aspects and business aspects for each agent providing the basic multimedia service. Such a techno-business analysis is then projected into a mathematical model dealing with the problem of the definition of incentives between the different agents involved in a collaborative service provision. Through the implementation of this model we aim at shaping the behaviour of each of the contributing agents modifying the level of profitability that the Service Portfolio yields to each of them.

  20. 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.

  1. Advanced optical position sensors for magnetically suspended wind tunnel models

    NASA Technical Reports Server (NTRS)

    Lafleur, S.

    1985-01-01

    A major concern to aerodynamicists has been the corruption of wind tunnel test data by model support structures, such as stings or struts. A technique for magnetically suspending wind tunnel models was considered by Tournier and Laurenceau (1957) in order to overcome this problem. This technique is now implemented with the aid of a Large Magnetic Suspension and Balance System (LMSBS) and advanced position sensors for measuring model attitude and position within the test section. Two different optical position sensors are discussed, taking into account a device based on the use of linear CCD arrays, and a device utilizing area CID cameras. Current techniques in image processing have been employed to develop target tracking algorithms capable of subpixel resolution for the sensors. The algorithms are discussed in detail, and some preliminary test results are reported.

  2. Acoustic test and analyses of three advanced turboprop models

    NASA Technical Reports Server (NTRS)

    Brooks, B. M.; Metzger, F. B.

    1980-01-01

    Results of acoustic tests of three 62.2 cm (24.5 inch) diameter models of the prop-fan (a small diameter, highly loaded. Multi-bladed variable pitch advanced turboprop) are presented. Results show that there is little difference in the noise produced by unswept and slightly swept designs. However, the model designed for noise reduction produces substantially less noise at test conditions simulating 0.8 Mach number cruise speed or at conditions simulating takeoff and landing. In the near field at cruise conditions the acoustically designed. In the far field at takeoff and landing conditions the acoustically designed model is 5 db quieter than unswept or slightly swept designs. Correlation between noise measurement and theoretical predictions as well as comparisons between measured and predicted acoustic pressure pulses generated by the prop-fan blades are discussed. The general characteristics of the pulses are predicted. Shadowgraph measurements were obtained which showed the location of bow and trailing waves.

  3. Fish Passage Assessment of an Advanced Hydropower Turbine and Conventional Turbine Using Blade-strike Modeling

    SciTech Connect

    Deng, Zhiqun; Carlson, Thomas J.; Dauble, Dennis D.; Ploskey, Gene R.

    2011-01-04

    In the Columbia and Snake River basins, several species of Pacific salmon were listed under the Endangered Species Act of 1973 due to significant declines of fish population. Dam operators and design engineers are thus faced with the task of making those hydroelectric facilities more ecologically friendly through changes in hydro-turbine design and operation. Public Utility District No. 2 of Grant County, Washington, applied for re-licensing from the U.S. Federal Energy Regulatory Commission to replace the 10 turbines at Wanapum Dam with advanced hydropower turbines that were designed to increase power generation and improve fish passage conditions. We applied both deterministic and stochastic blade-strike models to the newly installed turbine and an existing turbine. Modeled probabilities were compared to the results of a large-scale live fish survival study and a sensor fish study under the same operational parameters. Overall, injury rates predicted by the deterministic model were higher than experimental rates of injury while those predicted by the stochastic model were in close agreement with experiment results. Fish orientation at the time of entry into the plane of the leading edges of the turbine runner blades was an important factor contributing to uncertainty in modeled results. The advanced design turbine had slightly higher modeled injury rates than the existing turbine design; however, there was no statistical evidence that suggested significant differences in blade-strike injuries between the two turbines and the hypothesis that direct fish survival rate through the advanced hydropower turbine is equal or better than that through the conventional turbine could not be rejected.

  4. Advances in DOE modeling and optical performance for SMO applications

    NASA Astrophysics Data System (ADS)

    Carriere, James; Stack, Jared; Childers, John; Welch, Kevin; Himel, Marc D.

    2010-04-01

    The introduction of source mask optimization (SMO) to the design process addresses an urgent need for the 32nm node and beyond as alternative lithography approaches continue to push out. To take full advantage of SMO routines, an understanding of the characteristic properties of diffractive optical elements (DOEs) is required. Greater flexibility in the DOE output is needed to optimize lithographic process windows. In addition, new and tighter constraints on the DOEs used for off-axis illumination (OAI) are being introduced to precisely predict, control and reduce the effects of pole imbalance and stray light on the CD budget. We present recent advancements in the modeling and optical performance of these DOEs.

  5. Advanced Models for Aeroelastic Analysis of Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Keith, Theo G., Jr.; Mahajan, Aparajit

    1996-01-01

    This report describes an integrated, multidisciplinary simulation capability for aeroelastic analysis and optimization of advanced propulsion systems. This research is intended to improve engine development, acquisition, and maintenance costs. One of the proposed simulations is aeroelasticity of blades, cowls, and struts in an ultra-high bypass fan. These ducted fans are expected to have significant performance, fuel, and noise improvements over existing engines. An interface program was written to use modal information from COBSTAN and NASTRAN blade models in aeroelastic analysis with a single rotation ducted fan aerodynamic code.

  6. Advancing Models and Evaluation of Cumulus, Climate and Aerosol Interactions

    SciTech Connect

    Gettelman, Andrew

    2015-10-27

    This project was successfully able to meet its’ goals, but faced some serious challenges due to personnel issues. Nonetheless, it was largely successful. The Project Objectives were as follows: 1. Develop a unified representation of stratifom and cumulus cloud microphysics for NCAR/DOE global community models. 2. Examine the effects of aerosols on clouds and their impact on precipitation in stratiform and cumulus clouds. We will also explore the effects of clouds and precipitation on aerosols. 3. Test these new formulations using advanced evaluation techniques and observations and release

  7. Advances in Electromagnetic Modelling through High Performance Computing

    SciTech Connect

    Ko, K.; Folwell, N.; Ge, L.; Guetz, A.; Lee, L.; Li, Z.; Ng, C.; Prudencio, E.; Schussman, G.; Uplenchwar, R.; Xiao, L.; /SLAC

    2006-03-29

    Under the DOE SciDAC project on Accelerator Science and Technology, a suite of electromagnetic codes has been under development at SLAC that are based on unstructured grids for higher accuracy, and use parallel processing to enable large-scale simulation. The new modeling capability is supported by SciDAC collaborations on meshing, solvers, refinement, optimization and visualization. These advances in computational science are described and the application of the parallel eigensolver Omega3P to the cavity design for the International Linear Collider is discussed.

  8. Advancing LGBT Elder Policy and Support Services: The Massachusetts Model.

    PubMed

    Krinsky, Lisa; Cahill, Sean

    2017-04-04

    The Massachusetts-based LGBT Aging Project has trained elder service providers in affirming and culturally competent care for LGBT older adults, supported development of LGBT-friendly meal programs, and advanced LGBT equality under aging policy. Working across sectors, this innovative model launched the country's first statewide Legislative Commission on Lesbian, Gay, Bisexual, and Transgender Aging. Advocates are working with policymakers to implement key recommendations, including cultural competency training and data collection in statewide networks of elder services. The LGBT Aging Project's success provides a template for improving services and policy for LGBT older adults throughout the country.

  9. A 3D Full-Stokes Calving Model Applied to a West Greenland Outlet Glacier

    NASA Astrophysics Data System (ADS)

    Todd, Joe; Christoffersen, Poul; Zwinger, Thomas; Råback, Peter; Chauché, Nolwenn; Hubbard, Alun; Toberg, Nick; Luckman, Adrian; Benn, Doug; Slater, Donald; Cowton, Tom

    2017-04-01

    Iceberg calving from outlet glaciers accounts for around half of all mass loss from both the Greenland and Antarctic ice sheets. The diverse nature of calving and its complex links to both internal dynamics and external climate make it challenging to incorporate into models of glaciers and ice sheets. Consequently, calving represents one of the most significant uncertainties in predictions of future sea level rise. Here, we present results from a new 3D full-Stokes calving model developed in Elmer/Ice and applied to Store Glacier, the second largest outlet glacier in West Greenland. The calving model implements the crevasse depth criterion, which states that calving occurs when surface and basal crevasses penetrate the full thickness of the glacier. The model also implements a new 3D rediscretization approach and a time-evolution scheme which allow the calving front to evolve realistically through time. We use the model to test Store's sensitivity to two seasonal environmental processes believed to significantly influence calving: submarine melt undercutting and ice mélange buttressing. Store Glacier discharges 13.9 km3 of ice annually, and this calving rate shows a strong seasonal trend. We aim to reproduce this seasonal trend by forcing the model with present day levels of submarine melting and ice mélange buttressing. Sensitivity to changes in these frontal processes was also investigated, by forcing the model with a) increased submarine melt rates acting over longer periods of time and b) decreased mélange buttressing force acting over a reduced period. The model displays a range of observed calving behaviour and provides a good match to the observed seasonal evolution of the Store's terminus. The results indicate that ice mélange is the primary driver of the observed seasonal advance of the terminus and the associated seasonal variation in calving rate. The model also demonstrates a significant influence from submarine melting on calving rate. The results

  10. Advanced Numerical Prediction and Modeling of Tropical Cyclones Using WRF-NMM modeling system

    NASA Astrophysics Data System (ADS)

    Gopalakrishnan, S. G.; Rogers, R. F.; Marks, F. D.; Atlas, R.

    2007-12-01

    Dramatic improvement in tropical cyclone track forecasts have occurred through advancements in high quality observations, high speed computers and improvements in dynamical models. Similar advancements now need to be made for tropical cyclone intensity, structure and rainfall prediction. The Weather Research Forecasting Model (WRF) is a general purpose, multi-institutional mesoscale modeling system. A version of the WRF model called the HWRF/WRF-NMM modeling system, developed at the National Center for Environmental Protection (NCEP) was recently adopted for hurricane forecasting (Gopalakrishnan et al, 2006) by the National Hurricane Center (NHC). At the Hurricane Research Division (HRD/AOML/OAR) we are developing and further advancing a research version of this modeling system. This work is done in collaboration with the Developmental Test bed Center (DTC), Boulder, CO, Global Systems division (GSD/ESRL/OAR), Boulder, CO, The Air Resources Laboratory (ARL/OAR), Washington, D.C., the U.S. university community, the Indian Institute of Technology, IIT.Delhi, India, and the India Meteorological Department, New Delhi, India Our modeling effort includes advancing the WRF system for Ensemble Hurricane Forecasting, advancing our understanding of Ensemble-vs- High Resolution Forecasting of Hurricanes, advancing WRF/WRF-NMM with better analysis techniques (e.g. Four Dimensional Data Assimilation) for improving forecasts and above all, advancing our understanding of hurricane processes using a high resolution numerical modeling approach. Examples of some of these applications will be shown here. Reference: NCEP's Two-way-Interactive-Moving-Nest NMM-WRF modeling system for Hurricane Forecasting, S.G. Gopalakrishnan, N. Surgi, R. Tuleya, and Z. Janjic 27th Conference on Hurricanes and Tropical Meteorology, 24- 28 April 2006, Monterey, California.

  11. Drosophila models of Alzheimer's disease: advances, limits, and perspectives.

    PubMed

    Bouleau, Sylvina; Tricoire, Hervé

    2015-01-01

    Amyloid-β protein precursor (AβPP) and the microtubule-associated protein tau (MAPT) are the two key players involved in Alzheimer's disease (AD) and are associated with amyloid plaques and neurofibrillary tangles respectively, two key hallmarks of the disease. Besides vertebrate models, Drosophila models have been widely used to understand the complex events leading to AD in relation to aging. Drosophila benefits from the low redundancy of the genome which greatly simplifies the analysis of single gene disruption, sophisticated molecular genetic tools, and reduced cost compared to mammals. The aim of this review is to describe the recent advances in modeling AD using fly and to emphasize some limits of these models. Genetic studies in Drosophila have revealed some key aspects of the normal function of Appl and Tau, the fly homologues of AβPP and MAPT that may be disrupted during AD. Drosophila models have also been useful to uncover or validate several pathological pathways or susceptibility genes, and have been readily implemented in drug screening pipelines. We discuss some limitations of the current models that may arise from differences in structure of Appl and Tau compared to their human counterparts or from missing AβPP or MAPT protein interactors in flies. The advent of new genome modification technologies should allow the development of more realistic fly models and to better understand the relationship between AD and aging, taking advantage of the fly's short lifespan.

  12. Recent advances in animal model experimentation in autism research.

    PubMed

    Tania, Mousumi; Khan, Md Asaduzzaman; Xia, Kun

    2014-10-01

    Autism, a lifelong neuro-developmental disorder is a uniquely human condition. Animal models are not the perfect tools for the full understanding of human development and behavior, but they can be an important place to start. This review focused on the recent updates of animal model research in autism. We have reviewed the publications over the last three decades, which are related to animal model study in autism. Animal models are important because they allow researchers to study the underlying neurobiology in a way that is not possible in humans. Improving the availability of better animal models will help the field to increase the development of medicines that can relieve disabling symptoms. Results from the therapeutic approaches are encouraging remarkably, since some behavioral alterations could be reversed even when treatment was performed on adult mice. Finding an animal model system with similar behavioral tendencies as humans is thus vital for understanding the brain mechanisms, supporting social motivation and attention, and the manner in which these mechanisms break down in autism. The ongoing studies should therefore increase the understanding of the biological alterations associated with autism as well as the development of knowledge-based treatments therapy for those struggling with autism. In this review, we have presented recent advances in research based on animal models of autism, raising hope for understanding the disease biology for potential therapeutic intervention to improve the quality of life of autism individuals.

  13. The Propulsion Model of Creative Contributions Applied to the Arts and Letters.

    ERIC Educational Resources Information Center

    Sternberg, Robert J.; Kaufman, James C.; Pretz, Jean E.

    2001-01-01

    This article applies a propulsion model of creative contributions to the arts and letters. It opens with a general discussion of creative contributions and reviews existing models before describing the propulsion model and suggesting eight types of contributions that follow from this model. Examples illustrate use of the model in understanding…

  14. Applying horizontal diffusion on pressure surface to mesoscale models on terrain-following coordinates

    Treesearch

    Hann-Ming Henry Juang; Ching-Teng Lee; Yongxin Zhang; Yucheng Song; Ming-Chin Wu; Yi-Leng Chen; Kevin Kodama; Shyh-Chin Chen

    2005-01-01

    The National Centers for Environmental Prediction regional spectral model and mesoscale spectral model (NCEP RSM/MSM) use a spectral computation on perturbation. The perturbation is defined as a deviation between RSM/MSM forecast value and their outer model or analysis value on model sigma-coordinate surfaces. The horizontal diffusion used in the models applies...

  15. Multiscale and Multiphysics Modeling of Additive Manufacturing of Advanced Materials

    NASA Technical Reports Server (NTRS)

    Liou, Frank; Newkirk, Joseph; Fan, Zhiqiang; Sparks, Todd; Chen, Xueyang; Fletcher, Kenneth; Zhang, Jingwei; Zhang, Yunlu; Kumar, Kannan Suresh; Karnati, Sreekar

    2015-01-01

    The objective of this proposed project is to research and develop a prediction tool for advanced additive manufacturing (AAM) processes for advanced materials and develop experimental methods to provide fundamental properties and establish validation data. Aircraft structures and engines demand materials that are stronger, useable at much higher temperatures, provide less acoustic transmission, and enable more aeroelastic tailoring than those currently used. Significant improvements in properties can only be achieved by processing the materials under nonequilibrium conditions, such as AAM processes. AAM processes encompass a class of processes that use a focused heat source to create a melt pool on a substrate. Examples include Electron Beam Freeform Fabrication and Direct Metal Deposition. These types of additive processes enable fabrication of parts directly from CAD drawings. To achieve the desired material properties and geometries of the final structure, assessing the impact of process parameters and predicting optimized conditions with numerical modeling as an effective prediction tool is necessary. The targets for the processing are multiple and at different spatial scales, and the physical phenomena associated occur in multiphysics and multiscale. In this project, the research work has been developed to model AAM processes in a multiscale and multiphysics approach. A macroscale model was developed to investigate the residual stresses and distortion in AAM processes. A sequentially coupled, thermomechanical, finite element model was developed and validated experimentally. The results showed the temperature distribution, residual stress, and deformation within the formed deposits and substrates. A mesoscale model was developed to include heat transfer, phase change with mushy zone, incompressible free surface flow, solute redistribution, and surface tension. Because of excessive computing time needed, a parallel computing approach was also tested. In addition

  16. Modelling of an advanced charging system for electric vehicles

    NASA Astrophysics Data System (ADS)

    Hassan Jaafar, Abdul; Rahman, Ataur; Mohiuddin, A. K. M.; Rashid, Mahbubur

    2017-03-01

    Climate Change is recognized as one of the greatest environmental problem facing the World today and it has long been appreciated by governments that reducing the impact of the internal combustion (IC) engine powered motor vehicle has an important part to play in addressing this threat. In Malaysia, IC engine powered motor vehicle accounts almost 90% of the national greenhouse gas (GHG) emissions. The need to reduce the emission is paramount, as Malaysia has pledged to reduce 40% of CO2 intensity by 2020 from 2005 level by 25% of improvement in average fuel consumption. The introduction of electric vehicles (EVs) is one of the initiatives. However in terms of percentage, the electric vehicles have not been commonly used by people nowadays and one of the reasons is lack in charging infrastructure especially when cars are on the road. The aim of this study is to simulate and model an advanced charging system for the charging infrastructure of EVs/HEVs all over the nation with slow charging mode with charging current 25 A, medium charging mode with charging current 50 A and fast charging mode with charging current 100 A. The slow charging mode is proposed for residence, medium charging mode for office parking lots, and fast charging mode is called fast charging track for charging station on road. With three modes charger topology, consumers could choose a suitable mode for their car based on their need. The simulation and experiment of advanced charging system has been conducted on a scale down battery pack of nominal voltage of 3.75 V and capacity of 1020 mAh. Result shows that the battery could be charging less than 1 hour with fast charging mode. However, due to limitation of Tenaga Nasional Berhad (TNB) power grid, the maximum 50 A current is considered to be the optimized passive mode for the EV’s battery charging system. The developed advanced charger prototype performance has been compared with the simulation result and conventional charger performance, the

  17. Incorporating a Full-Physics Meteorological Model into an Applied Atmospheric Dispersion Modeling System

    SciTech Connect

    Berg, Larry K.; Allwine, K Jerry; Rutz, Frederick C.

    2004-08-23

    A new modeling system has been developed to provide a non-meteorologist with tools to predict air pollution transport in regions of complex terrain. This system couples the Penn State/NCAR Mesoscale Model 5 (MM5) with Earth Tech’s CALMET-CALPUFF system using a unique Graphical User Interface (GUI) developed at Pacific Northwest National Laboratory. This system is most useful in data-sparse regions, where there are limited observations to initialize the CALMET model. The user is able to define the domain of interest, provide details about the source term, and enter a surface weather observation through the GUI. The system then generates initial conditions and time constant boundary conditions for use by MM5. MM5 is run and the results are piped to CALPUFF for the dispersion calculations. Contour plots of pollutant concentration are prepared for the user. The primary advantages of the system are the streamlined application of MM5 and CALMET, limited data requirements, and the ability to run the coupled system on a desktop or laptop computer. In comparison with data collected as part of a field campaign, the new modeling system shows promise that a full-physics mesoscale model can be used in an applied modeling system to effectively simulate locally thermally-driven winds with minimal observations as input. An unexpected outcome of this research was how well CALMET represented the locally thermally-driven flows.

  18. [Aquatic ecosystem modelling approach: temperature and water quality models applied to Oualidia and Nador lagoons].

    PubMed

    Idrissi, J Lakhdar; Orbi, A; Hilmi, K; Zidane, F; Moncef, M

    2005-07-01

    The objective of this work is to develop an aquatic ecosystem and apply it on Moroccan lagoon systems. This model will keep us abreast of the yearly development of the main parameters that characterize these ecosystems while integrating all the data that have so far been acquired. Within this framework, a simulation model of the thermal system and a model of the water quality have been elaborated. These models, which have been simulated on the lagoon of Oualidia (North of Morocco) and validated on the lagoon of Nador (North West Mediterranean), permit to foresee the cycles of temperature of the surface and the parameters of the water quality (dissolved oxygen and biomass phytoplankton) by using meteorological information, specific features and in situ measurements in the studied sites. The elaborated model, called Zero-Dimensional, simulates the average conduct of the site during the time of variable states that are representatives of the studied ecosystem. This model will provide answers for the studied phenomena and is a work tool adequate for numerical simplicity.

  19. Demasking the integrated value of discharge - Advanced sensitivity analysis on the components of hydrological models

    NASA Astrophysics Data System (ADS)

    Guse, Björn; Pfannerstill, Matthias; Gafurov, Abror; Fohrer, Nicola; Gupta, Hoshin

    2016-04-01

    The hydrologic response variable most often used in sensitivity analysis is discharge which provides an integrated value of all catchment processes. The typical sensitivity analysis evaluates how changes in the model parameters affect the model output. However, due to discharge being the aggregated effect of all hydrological processes, the sensitivity signal of a certain model parameter can be strongly masked. A more advanced form of sensitivity analysis would be achieved if we could investigate how the sensitivity of a certain modelled process variable relates to the changes in a parameter. Based on this, the controlling parameters for different hydrological components could be detected. Towards this end, we apply the approach of temporal dynamics of parameter sensitivity (TEDPAS) to calculate the daily sensitivities for different model outputs with the FAST method. The temporal variations in parameter dominance are then analysed for both the modelled hydrological components themselves, and also for the rates of change (derivatives) in the modelled hydrological components. The daily parameter sensitivities are then compared with the modelled hydrological components using regime curves. Application of this approach shows that when the corresponding modelled process is investigated instead of discharge, we obtain both an increased indication of parameter sensitivity, and also a clear pattern showing how the seasonal patterns of parameter dominance change over time for each hydrological process. By relating these results with the model structure, we can see that the sensitivity of model parameters is influenced by the function of the parameter. While capacity parameters show more sensitivity to the modelled hydrological component, flux parameters tend to have a higher sensitivity to rates of change in the modelled hydrological component. By better disentangling the information hidden in the discharge values, we can use sensitivity analyses to obtain a clearer signal

  20. In the spine or in the brain? Recent advances in pain neuroscience applied in the intervention for low back pain.

    PubMed

    Nijs, Jo; Clark, Jacqui; Malfliet, Anneleen; Ickmans, Kelly; Voogt, Lennard; Don, Sanneke; den Bandt, Hester; Goubert, Dorien; Kregel, Jeroen; Coppieters, Iris; Dankaerts, Wim

    2017-01-01

    Conservative, surgical and pharmacological strategies for chronic low back pain (CLBP) management offer at best modest effect sizes in reducing pain and related disability, indicating a need for improvement. Such improvement may be derived from applying contemporary pain neuroscience to the management of CLBP. Current interventions for people with CLBP are often based entirely on a "biomedical" or "psychological" model without consideration of information concerning underlying pain mechanisms and contemporary pain neuroscience. Here we update readers with our current understanding of pain in people with CLBP, showing that CLBP is not limited to spinal impairments, but is also characterised by brain changes, including functional connectivity reorganisation in several brain regions and increased activation in brain regions of the so-called 'pain matrix' (or 'pain connectome'). Indeed, in a subgroup of the CLBP population brain changes associated with the presence of central sensitisation are seen. Understanding the role of these brain changes in CLBP improves our understanding not only of pain symptoms, but also of prevalent CLBP associated comorbidities such as sleep disturbances and fear avoidance behaviour. Applying contemporary pain neuroscience to improve care for people with CLBP includes identifying relevant pain mechanisms to steer intervention, addressing sleep problems and optimising exercise and activity interventions. This approach includes cognitively preparing patients for exercise therapy using (therapeutic) pain neuroscience education, followed by cognition-targeted functional exercise therapy.