Science.gov

Sample records for support structure modeling

  1. Rectangular Array Model Supporting Students' Spatial Structuring in Learning Multiplication

    ERIC Educational Resources Information Center

    Shanty, Nenden Octavarulia; Wijaya, Surya

    2012-01-01

    We examine how rectangular array model can support students' spatial structuring in learning multiplication. To begin, we define what we mean by spatial structuring as the mental operation of constructing an organization or form for an object or set of objects. For that reason, the eggs problem was chosen as the starting point in which the…

  2. Experimental-based modeling of a support structure as part of a full system model

    SciTech Connect

    CARNE,THOMAS G.; DOHRMANN,CLARK R.

    2000-02-29

    Structural dynamic systems are often attached to a support structure to simulate proper boundary conditions during testing. In some cases the support structure is fairly simple and can be modeled by discrete springs and dampers. In other cases the desired test conditions necessitate the use of a support structural that introduces dynamics of its own. For such cases a more complex structural dynamic model is required to simulate the response of the full combined system. In this paper experimental frequency response functions, admittance function modeling concepts, and least squares reductions are used to develop a support structure model including both translational and rotational degrees of freedom at an attachment location. Subsequently, the modes of the support structure are estimated, and a NASTRAN model is created for attachment to the tested system.

  3. Scour around Support Structures of Scaled Model Marine Hydrokinetic Devices

    NASA Astrophysics Data System (ADS)

    Volpe, M. A.; Beninati, M. L.; Krane, M.; Fontaine, A.

    2013-12-01

    Experiments are presented to explore scour due to flows around support structures of marine hydrokinetic (MHK) devices. Three related studies were performed to understand how submergence, scour condition, and the presence of an MHK device impact scour around the support structure (cylinder). The first study focuses on clear-water scour conditions for a cylinder of varying submergence: surface-piercing and fully submerged. The second study centers on three separate scour conditions (clear-water, transitional and live-bed) around the fully submerged cylinder. Lastly, the third study emphasizes the impact of an MHK turbine on scour around the support structure, in live-bed conditions. Small-scale laboratory testing of model devices can be used to help predict the behavior of MHK devices at full-scale. Extensive studies have been performed on single cylinders, modeling bridge piers, though few have focused on fully submerged structures. Many of the devices being used to harness marine hydrokinetic energy are fully submerged in the flow. Additionally, scour hole dimensions and scour rates have not been addressed. Thus, these three studies address the effect of structure blockage/drag, and the ambient scour conditions on scour around the support structure. The experiments were performed in the small-scale testing platform in the hydraulic flume facility (9.8 m long, 1.2 m wide and 0.4 m deep) at Bucknell University. The support structure diameter (D = 2.54 cm) was held constant for all tests. The submerged cylinder (l/D = 5) and sediment size (d50 = 790 microns) were held constant for all three studies. The MHK device (Dturbine = 10.2 cm) is a two-bladed horizontal axis turbine and the rotating shaft is friction-loaded using a metal brush motor. For each study, bed form topology was measured after a three-hour time interval using a traversing two-dimensional bed profiler. During the experiments, scour hole depth measurements at the front face of the support structure

  4. Biologically-supported structural model for a viral satellite RNA

    PubMed Central

    Ashton, Peter; Wu, Baodong; D'Angelo, Jessica; Grigull, Jörg; White, K. Andrew

    2015-01-01

    Satellite RNAs (satRNAs) are a class of small parasitic RNA replicon that associate with different viruses, including plus-strand RNA viruses. Because satRNAs do not encode a polymerase or capsid subunit, they rely on a companion virus to provide these proteins for their RNA replication and packaging. SatRNAs recruit these and other required factors via their RNA sequences and structures. Here, through a combination of chemical probing analysis of RNA structure, phylogenetic structural comparisons, and viability assays of satRNA mutants in infected cells, the biological importance of a deduced higher-order structure for a 619 nt long tombusvirus satRNA was assessed. Functionally-relevant secondary and tertiary RNA structures were identified throughout the length of the satRNA. Notably, a 3′-terminal segment was found to adopt two mutually-exclusive RNA secondary structures, both of which were required for efficient satRNA accumulation. Accordingly, these alternative conformations likely function as a type of RNA switch. The RNA switch was also found to engage in a required long-range kissing-loop interaction with an upstream sequence. Collectively, these results establish a high level of conformational complexity within this small parasitic RNA and provide a valuable structural framework for detailed mechanistic studies. PMID:26384416

  5. A qualitative model structure sensitivity analysis method to support model selection

    NASA Astrophysics Data System (ADS)

    Van Hoey, S.; Seuntjens, P.; van der Kwast, J.; Nopens, I.

    2014-11-01

    The selection and identification of a suitable hydrological model structure is a more challenging task than fitting parameters of a fixed model structure to reproduce a measured hydrograph. The suitable model structure is highly dependent on various criteria, i.e. the modeling objective, the characteristics and the scale of the system under investigation and the available data. Flexible environments for model building are available, but need to be assisted by proper diagnostic tools for model structure selection. This paper introduces a qualitative method for model component sensitivity analysis. Traditionally, model sensitivity is evaluated for model parameters. In this paper, the concept is translated into an evaluation of model structure sensitivity. Similarly to the one-factor-at-a-time (OAT) methods for parameter sensitivity, this method varies the model structure components one at a time and evaluates the change in sensitivity towards the output variables. As such, the effect of model component variations can be evaluated towards different objective functions or output variables. The methodology is presented for a simple lumped hydrological model environment, introducing different possible model building variations. By comparing the effect of changes in model structure for different model objectives, model selection can be better evaluated. Based on the presented component sensitivity analysis of a case study, some suggestions with regard to model selection are formulated for the system under study: (1) a non-linear storage component is recommended, since it ensures more sensitive (identifiable) parameters for this component and less parameter interaction; (2) interflow is mainly important for the low flow criteria; (3) excess infiltration process is most influencing when focussing on the lower flows; (4) a more simple routing component is advisable; and (5) baseflow parameters have in general low sensitivity values, except for the low flow criteria.

  6. Conceptual design study of a solar concentrator/support structure: A three dimensional finite element model

    NASA Astrophysics Data System (ADS)

    Purasinghe, R.; Laug, K. K.

    1993-11-01

    Under the space environment the paraboloid solar concentrators and support structures can deform and hence the focal point of the concentrators can diffuse. If this diffusion is large, energy will not concentrate on the thruster as desired. This paper addresses this aspect of pointing and accuracy analysis of solar concentrators, due to equivalent thrust loads. The previous studies were limited to the concentrator system being modeled with a simplified finite element model that includes only the support struts and torus. The torus model was made up of several equal length beams. The simple model did not contain the paraboloid reflector, and assumes the reflector does not effect the deformation of the torus. In the present study the inflated parabolic reflector is included in the model. The results demonstrate the nonuniform displacements on the reflector that confirms the reflector's potato chipping effect.

  7. Conceptual Design Study of a Solar Concentrator/Support Structure: A Three Dimensional Finite Element Model

    NASA Astrophysics Data System (ADS)

    Purasinghe, R.

    1993-01-01

    Under the space environment the paraboloid solar concentrators and support structures can deform and hence the focal point of the concentrators can diffuse. If this diffusion is large, energy will not concentrate on the thruster as desired. This paper addresses this aspect of pointing and accuracy analysis of solar concentrators, due to equivalent thrust loads. The previous studies were limited to the concentrator system being modeled with a simplified finite element model that includes only the support struts and torus. The torus model was made up of several equal length beams. The simple model did not contain the paraboloid reflector, and assumes the reflector does not affect the deformation of the torus. In the present study the inflated parabolic reflector is included in the model. The results demonstrate the non uniform displacements on the reflector that confirms the reflector's potato chipping effect.

  8. Testing a structural model of young driver willingness to uptake Smartphone Driver Support Systems.

    PubMed

    Kervick, Aoife A; Hogan, Michael J; O'Hora, Denis; Sarma, Kiran M

    2015-10-01

    There is growing interest in the potential value of using phone applications that can monitor driver behaviour (Smartphone Driver Support Systems, 'SDSSs') in mitigating risky driving by young people. However, their value in this regard will only be realised if young people are willing to use this technology. This paper reports the findings of a study in which a novel structural model of willingness to use SDSSs was tested. Grounded in the driver monitoring and Technology Acceptance (TA) research literature, the model incorporates the perceived risks and gains associated with potential SDSS usage and additional social cognitive factors, including perceived usability and social influences. A total of 333 smartphone users, aged 18-24, with full Irish driving licenses completed an online questionnaire examining willingness or Behavioural Intention (BI) to uptake a SDSS. Following exploratory and confirmatory factor analyses, structural equation modelling indicated that perceived gains and social influence factors had significant direct effects on BI. Perceived risks and social influence also had significant indirect effects on BI, as mediated by perceived gains. Overall, this model accounted for 72.5% of the variance in willingness to uptake SDSSs. Multi-group structural models highlighted invariance of effects across gender, high and low risk drivers, and those likely or unlikely to adopt novel phone app technologies. These findings have implications for our understanding of the willingness of young drivers to adopt and use SDSSs, and highlight potential factors that could be targeted in behavioural change interventions seeking to improve usage rates. PMID:26277411

  9. Personality and support for universal human rights: a review and test of a structural model.

    PubMed

    McFarland, Sam

    2010-12-01

    All individual differences that predict support for international human rights are first reviewed: support for human rights is linked most positively to "globalism" (other international and environmental concerns), "identification with all humanity," principled moral reasoning, benevolence, and dispositional empathy. It is related most negatively to ethnocentrism and its root dispositions, the social dominance orientation, and authoritarianism. Other correlates are also noted. Secondly, a structural model of the effects of authoritarianism, social dominance, ethnocentrism and identification with all humanity upon commitment to human rights is presented and tested. Across 2 studies (Study 1, N=218 nonstudent adults; Study 2, N=102 university students), ethnocentrism and identification with all humanity directly predicted human rights commitment. The effects of authoritarianism upon this commitment were fully mediated through enhanced ethnocentrism and reduced identification with all humanity. The effects of social dominance were similar, but its direct effect upon human rights commitment remained significant and was not, in the second study, mediated by reduced dispositional empathy. PMID:21039530

  10. Analysis of pulsed eddy current data using regression models for steam generator tube support structure inspection

    NASA Astrophysics Data System (ADS)

    Buck, J. A.; Underhill, P. R.; Morelli, J.; Krause, T. W.

    2016-02-01

    Nuclear steam generators (SGs) are a critical component for ensuring safe and efficient operation of a reactor. Life management strategies are implemented in which SG tubes are regularly inspected by conventional eddy current testing (ECT) and ultrasonic testing (UT) technologies to size flaws, and safe operating life of SGs is predicted based on growth models. ECT, the more commonly used technique, due to the rapidity with which full SG tube wall inspection can be performed, is challenged when inspecting ferromagnetic support structure materials in the presence of magnetite sludge and multiple overlapping degradation modes. In this work, an emerging inspection method, pulsed eddy current (PEC), is being investigated to address some of these particular inspection conditions. Time-domain signals were collected by an 8 coil array PEC probe in which ferromagnetic drilled support hole diameter, depth of rectangular tube frets and 2D tube off-centering were varied. Data sets were analyzed with a modified principal components analysis (MPCA) to extract dominant signal features. Multiple linear regression models were applied to MPCA scores to size hole diameter as well as size rectangular outer diameter tube frets. Models were improved through exploratory factor analysis, which was applied to MPCA scores to refine selection for regression models inputs by removing nonessential information.

  11. Vessel structural support system

    SciTech Connect

    Jenko, J.X.; Ott, H.L.; Wilson, R.M.; Wepfer, R.M.

    1992-10-06

    Vessel structural support system for laterally and vertically supporting a vessel, such as a nuclear steam generator having an exterior bottom surface and a side surface thereon is disclosed. The system includes a bracket connected to the bottom surface. A support column is pivotally connected to the bracket for vertically supporting the steam generator. The system also includes a base pad assembly connected pivotally to the support column for supporting the support column and the steam generator. The base pad assembly, which is capable of being brought to a level position by turning leveling nuts, is anchored to a floor. The system further includes a male key member attached to the side surface of the steam generator and a female stop member attached to an adjacent wall. The male key member and the female stop member coact to laterally support the steam generator. Moreover, the system includes a snubber assembly connected to the side surface of the steam generator and also attached to the adjacent wall for dampening lateral movement of the steam generator. In addition, the system includes a restraining member of flat'' attached to the side surface of the steam generator and a bumper attached to the adjacent wall. The flat and the bumper coact to further laterally support the steam generator. 19 figs.

  12. Vessel structural support system

    DOEpatents

    Jenko, James X.; Ott, Howard L.; Wilson, Robert M.; Wepfer, Robert M.

    1992-01-01

    Vessel structural support system for laterally and vertically supporting a vessel, such as a nuclear steam generator having an exterior bottom surface and a side surface thereon. The system includes a bracket connected to the bottom surface. A support column is pivotally connected to the bracket for vertically supporting the steam generator. The system also includes a base pad assembly connected pivotally to the support column for supporting the support column and the steam generator. The base pad assembly, which is capable of being brought to a level position by turning leveling nuts, is anchored to a floor. The system further includes a male key member attached to the side surface of the steam generator and a female stop member attached to an adjacent wall. The male key member and the female stop member coact to laterally support the steam generator. Moreover, the system includes a snubber assembly connected to the side surface of the steam generator and also attached to the adjacent wall for dampening lateral movement of the steam generator. In addition, the system includes a restraining member of "flat" attached to the side surface of the steam generator and a bumper attached to the adjacent wall. The flat and the bumper coact to further laterally support the steam generator.

  13. Aerospace structures supportability

    NASA Astrophysics Data System (ADS)

    Smith, Howard Wesley

    1989-04-01

    This paper is about supportability in its general sense, with emphasis on aerospace structures. Reliability and maintainability (R&M) are described and defined from the standpoint of both structural analysis. Accessability, inspectability, and replaceability are described as design attributes. Reliability and probability of failure are shown to be in the domain of the analysis. Availability and replaceability are traditional logistic responsibilities which are influenced by supportability engineers. The USAF R&M 2000 process is described, and the R&M 1988 Workshop at Wright-Patterson Air Force Base is also included in the description.

  14. Integrated support structure

    NASA Technical Reports Server (NTRS)

    Bruneau, Stephen D.; Campbell, John T.; Struven, Christopher A.

    1990-01-01

    This Major Qualifying Project is part of the Advanced Space Design Program at WPI. The goal is to design a support structure for a NASA GetAway Special experimental canister. The payload integration, weight, volume, and structural integrity of the canister as specified by NASA guidelines were studied. The end result is a complete set of design drawings with interface drawings and data to specify the design and leave a base on which the next group can concentrate.

  15. Experimental support and estimate of the accuracy of the water flow model in structured soils

    NASA Astrophysics Data System (ADS)

    Nikulina, M.

    2003-04-01

    The set of models of water flow and solute transport was developed. It takes into account spatial and time variability of soil properties and a complex structure of a soil pore space. However, its limited by physically justified methods of experimental definition of parameters. The important stage of the work with the models is checking their adequacy to described processes. It is possible only at a presence of the qualitative experi-mental data received under conditions, reproduced by model. According to this, the aim of the work is the support of methods of experimental maintenance of water flow models with taking into account of structure of soil porosity and evaluation of conditions of application of mathematical models of a dif-ferent level. The field experiments were conducted in Suzdal (Russia, Vladimirskaja oblast), in June and July 1997. The soil cover of this region has high complexity, in which grey forest soils are dominant. Genetic horizons of the grey forest soils are well structured, this causes the presence in soil profile the macropores. The field investigation consisted of three big parts: (1) the morphological research of the genetic horizons of the grey forest soil; (2) investigation of the soil filtration properties by the tube with a constant head and vacuum-infiltrometer methods; (3) study of water movement at different intensity of the irrigation. Experiments were conducted on three sets called <А>, <В > and <С>. The plots had 1m x 1m a size and were equipped with the hole for measurement of soil water content by the neutron hygrometer and by the tensiometers. In labo-ratory conditions the following properties of soil were determined: density of soil, texture, porosity of the aggregates, shrinkage characteristics of soil fraction in diameter of 3-5 mm. For the simulation the model "MACRO" (Jarvis et al, 1991) was used in the work. Adequacy of the model descriptions of the field data were estimated by visual comparison of measured and

  16. Structuring a life support program using evidence-based practice and the Magnet model for successful patient outcomes.

    PubMed

    Krugman, Mary; Paston, Kristin

    2013-01-01

    Integrating life support activities into an acute care academic hospital structure using evidence-based practice and the Magnet Model framework provides program operations and outcomes that are cost effective, link quality to life support professional development, and demonstrate excellence patient safety outcomes. PMID:23703271

  17. Supporting people with dementia to walkabout safely outdoors: development of a structured model of assessment.

    PubMed

    Bantry White, Eleanor; Montgomery, Paul

    2016-07-01

    People with dementia while missing are at risk of harm including death. Yet, welfare concerns arise when freedom to walkabout outdoors is restricted and in particular, getting lost is a risk factor for admission to long-term care. Accurate methods of assessing the risks posed to community-dwelling people with dementia from getting lost are needed to ensure intervention is proportionate. Currently available assessment tools focus upon the identification of dementia-related changes in a person's walking behaviour, traditionally referred to as 'wandering'. 'Wandering' and getting lost are conceptually distinct; measures of 'wandering' are not sufficient to support the assessment of risk while walking outdoors. The objective of this study was to develop an assessment schedule that can evaluate safety in community-dwelling people with dementia who walkabout outdoors. A structured assessment schedule was generated from research on the aetiology of getting lost, a review of existing assessment tools, an observational study of incidents of getting lost and qualitative data from families experiencing this issue. A content validity study was then undertaken with a panel of 17 health and social care practitioners and researchers in the field. A schedule of 7 domains and 38 items was generated, 33 of which were deemed valid by the expert panel. Panel feedback suggests the schedule needs to be used flexibly to reflect an individual's unique living circumstances. Reflecting the complex aetiology of getting lost, considerable challenges exist when assessing risk in this field. The implications of this study for practitioners are discussed with reference to the merits of narrative and structured models of assessment, and the balance between objective safety and subjective well-being that is required when making decisions about intervention. The direction of further research is examined as a means of supporting professional assessment of this complex issue. PMID:25817065

  18. The Self-Esteem, Perceived Social Support and Hopelessness in Adolescents: The Structural Equation Modeling

    ERIC Educational Resources Information Center

    Savi Cakar, Firdevs; Karatas, Zeynep

    2012-01-01

    In this study, a developed model to explain a causal relationship between adolescent's self-esteem, perceived social support and hopelessness is tested. The purpose of the study is to explore the relationship between self-esteem, perceived social support and hopelessness in adolescents. A total of 257 adolescents, including 143 female and 114…

  19. Supporting Students in Learning with Multiple Representation to Improve Student Mental Models on Atomic Structure Concepts

    ERIC Educational Resources Information Center

    Sunyono; Yuanita, L.; Ibrahim, M.

    2015-01-01

    The aim of this research is identify the effectiveness of a multiple representation-based learning model, which builds a mental model within the concept of atomic structure. The research sample of 108 students in 3 classes is obtained randomly from among students of Mathematics and Science Education Studies using a stratified random sampling…

  20. Structural Model of the Bilitranslocase Transmembrane Domain Supported by NMR and FRET Data

    PubMed Central

    Choudhury, Amrita Roy; Sikorska, Emilia; van den Boom, Johannes; Bayer, Peter; Popenda, Łukasz; Szutkowski, Kosma; Jurga, Stefan; Bonomi, Massimiliano; Sali, Andrej; Zhukov, Igor; Passamonti, Sabina; Novič, Marjana

    2015-01-01

    We present a 3D model of the four transmembrane (TM) helical regions of bilitranslocase (BTL), a structurally uncharacterized protein that transports organic anions across the cell membrane. The model was computed by considering helix-helix interactions as primary constraints, using Monte Carlo simulations. The interactions between the TM2 and TM3 segments have been confirmed by Förster resonance energy transfer (FRET) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy, increasing our confidence in the model. Several insights into the BTL transport mechanism were obtained by analyzing the model. For example, the observed cis-trans Leu-Pro peptide bond isomerization in the TM3 fragment may indicate a key conformational change during anion transport by BTL. Our structural model of BTL may facilitate further studies, including drug discovery. PMID:26291722

  1. Assessment of longwall-roof behavior and support loading by linear elastic modeling of the support structure. Report of Investigations/1987

    SciTech Connect

    Barczak, T.M.; Burton, W.S.

    1987-01-01

    Longwall-roof behavior is characterized by strata displacements in both the face-to-waste (horizontal) and roof-to-floor (vertical) directions. The roof-support structure provides resistance to this motion by translation of these displacements into vertical and horizontal support loading. Observations indicate that the shield reacts with both a vertical and horizontal force to uniaxial convergence (displacement). However, there are different magnitudes depending on whether the displacement is vertical or horizontal. This makes it possible to use supports as monitors of strata activity and loading. The Bureau of Mines examined this behavior using a linear elastic model of the support structure with two degrees of freedom. Vertical and horizontal load reactions were related to associated displacement actions of the strata. This was done by determining the stiffness of the shield under controlled vertical and horizontal displacement motions in the Bureau's mine roof simulator. The report provides example predictions of strata convergence and isolation of horizontal support loading due to vertical roof convergence using the linear elastic shield model. The report also examines efforts to determine strata behavior by direct measurement of support displacement.

  2. Providing mentorship support to general surgery residents: a model for structured group facilitation

    PubMed Central

    Champion, Caitlin; Bennett, Sean; Carver, David; El Tawil, Karim; Fabbro, Sarah; Howatt, Neil; Noei, Farahnaz; Rae, Rachel; Haggar, Fatima; Arnaout, Angel

    2015-01-01

    Summary Mentorship is foundational to surgical training, with recognized benefits for both mentees and mentors. The University of Ottawa General Surgery Mentorship Program was developed as a module-based group facilitation program to support inclusive personal and professional development of junior general surgery residents. The group format provided an opportunity for both vertical and horizontal mentorship relationships between staff mentors and resident mentees. Perceived benefits of program participants were evaluated at the conclusion of the first year of the program. The program was well-received by staff and resident participants and may provide a time-efficient and inclusive mentorship structure with the additional benefit of peer support. We review the development and implementation of the program to date and share our mentorship experience to encourage the growth of formal mentorship opportunities within general surgery training programs. PMID:26424687

  3. Modeling of Global BEAM Structure for Evaluation of MMOD Impacts to Support Development of a Health Monitoring System

    NASA Technical Reports Server (NTRS)

    Lyle, Karen H.; Vassilakos, Gregory J.

    2015-01-01

    This report summarizes the initial modeling of the global response of the Bigelow Expandable Activity Module (BEAM) to micrometeorite and orbital debris(MMOD) impacts using a structural, nonlinear, transient dynamic, finite element code. These models complement the on-orbit deployment of the Distributed Impact Detection System (DIDS) to support structural health monitoring studies. Two global models were developed. The first focused exclusively on impacts on the soft-goods (fabric-envelop) portion of BEAM. The second incorporates the bulkhead to support understanding of bulkhead impacts. These models were exercised for random impact locations and responses monitored at the on-orbit sensor locations. The report concludes with areas for future study.

  4. Structural geology and geophysics as a support to build a hydrogeologic model of granite rock

    NASA Astrophysics Data System (ADS)

    Martinez-Landa, Lurdes; Carrera, Jesús; Pérez-Estaún, Andrés; Gómez, Paloma; Bajos, Carmen

    2016-06-01

    A method developed for low-permeability fractured media was applied to understand the hydrogeology of a mine excavated in a granitic pluton. This method includes (1) identifying the main groundwater-conducting features of the medium, such as the mine, dykes, and large fractures, (2) implementing this factors as discrete elements into a three-dimensional numerical model, and (3) calibrating these factors against hydraulic data . A key question is how to identify preferential flow paths in the first step. Here, we propose a combination of several techniques. Structural geology, together with borehole sampling, geophysics, hydrogeochemistry, and local hydraulic tests aided in locating all structures. Integration of these data yielded a conceptual model of the site. A preliminary calibration of the model was performed against short-term (< 1 day) pumping tests, which facilitated the characterization of some of the fractures. The hydraulic properties were then used for other fractures that, according to geophysics and structural geology, belonged to the same families. Model validity was tested by blind prediction of a long-term (4 months) large-scale (1 km) pumping test from the mine, which yielded excellent agreement with the observations. Model results confirmed the sparsely fractured nature of the pluton, which has not been subjected to glacial loading-unloading cycles and whose waters are of Na-HCO3 type.

  5. Modeling of Local BEAM Structure for Evaluation of MMOD Impacts to Support Development of a Health Monitoring System

    NASA Technical Reports Server (NTRS)

    Lyle, Karen H.; Vassilakos, Gregory J.

    2015-01-01

    This report summarizes initial modeling of the local response of the Bigelow Expandable Activity Module (BEAM) to micrometeorite and orbital debris (MMOD) impacts using a structural, non-linear, transient dynamic finite element code. Complementary test results for a local BEAM structure are presented for both hammer and projectile impacts. Review of these data provided guidance for the transient dynamic model development. The local model is intended to support predictions using the global BEAM model, described in a companion report. Two types of local models were developed. One mimics the simplified Soft-Goods (fabric envelop) part of the BEAM NASTRAN model delivered by the project. The second investigates through-the-thickness modeling challenges for MMOD-type impacts. Both the testing and the analysis summaries contain lessons learned and areas for future efforts.

  6. Data Collection Handbook to Support Modeling Impacts of Radioactive Material in Soil and Building Structures

    SciTech Connect

    Yu, Charley; Kamboj, Sunita; Wang, Cheng; Cheng, Jing-Jy

    2015-09-01

    This handbook is an update of the 1993 version of the Data Collection Handbook and the Radionuclide Transfer Factors Report to support modeling the impact of radioactive material in soil. Many new parameters have been added to the RESRAD Family of Codes, and new measurement methodologies are available. A detailed review of available parameter databases was conducted in preparation of this new handbook. This handbook is a companion document to the user manuals when using the RESRAD (onsite) and RESRAD-OFFSITE code. It can also be used for RESRAD-BUILD code because some of the building-related parameters are included in this handbook. The RESRAD (onsite) has been developed for implementing U.S. Department of Energy Residual Radioactive Material Guidelines. Hydrogeological, meteorological, geochemical, geometrical (size, area, depth), crops and livestock, human intake, source characteristic, and building characteristic parameters are used in the RESRAD (onsite) code. The RESRAD-OFFSITE code is an extension of the RESRAD (onsite) code and can also model the transport of radionuclides to locations outside the footprint of the primary contamination. This handbook discusses parameter definitions, typical ranges, variations, and measurement methodologies. It also provides references for sources of additional information. Although this handbook was developed primarily to support the application of RESRAD Family of Codes, the discussions and values are valid for use of other pathway analysis models and codes.

  7. Structural Dynamics Modeling of HIRENASD in Support of the Aeroelastic Prediction Workshop

    NASA Technical Reports Server (NTRS)

    Wieseman, Carol; Chwalowski, Pawel; Heeg, Jennifer; Boucke, Alexander; Castro, Jack

    2013-01-01

    An Aeroelastic Prediction Workshop (AePW) was held in April 2012 using three aeroelasticity case study wind tunnel tests for assessing the capabilities of various codes in making aeroelasticity predictions. One of these case studies was known as the HIRENASD model that was tested in the European Transonic Wind Tunnel (ETW). This paper summarizes the development of a standardized enhanced analytical HIRENASD structural model for use in the AePW effort. The modifications to the HIRENASD finite element model were validated by comparing modal frequencies, evaluating modal assurance criteria, comparing leading edge, trailing edge and twist of the wing with experiment and by performing steady and unsteady CFD analyses for one of the test conditions on the same grid, and identical processing of results.

  8. Genetic structure and bio-climatic modeling support allopatric over parapatric speciation along a latitudinal gradient

    PubMed Central

    2012-01-01

    Background Four of the five species of Telopea (Proteaceae) are distributed in a latitudinal replacement pattern on the south-eastern Australian mainland. In similar circumstances, a simple allopatric speciation model that identifies the origins of genetic isolation within temporal geographic separation is considered as the default model. However, secondary contact between differentiated lineages can result in similar distributional patterns to those arising from a process of parapatric speciation (where gene flow between lineages remains uninterrupted during differentiation). Our aim was to use the characteristic distributional patterns in Telopea to test whether it reflected the evolutionary models of allopatric or parapatric speciation. Using a combination of genetic evidence and environmental niche modelling, we focused on three main questions: do currently described geographic borders coincide with genetic and environmental boundaries; are there hybrid zones in areas of secondary contact between closely related species; did species distributions contract during the last glacial maximum resulting in distributional gaps even where overlap and hybridisation currently occur? Results Total genomic DNA was extracted from 619 individuals sampled from 36 populations representing the four species. Seven nuclear microsatellites (nSSR) and six chloroplast microsatellites (cpSSR) were amplified across all populations. Genetic structure and the signature of admixture in overlap zones was described using the Bayesian clustering methods implemented in STUCTURE and NewHybrids respectively. Relationships between chlorotypes were reconstructed as a median-joining network. Environmental niche models were produced for all species using environmental parameters from both the present day and the last glacial maximum (LGM). The nSSR loci amplified a total of 154 alleles, while data for the cpSSR loci produced a network of six chlorotypes. STRUCTURE revealed an optimum number of five

  9. GAIA - a generalizable, extensible structure for integrating games, models and social networking to support decision makers

    NASA Astrophysics Data System (ADS)

    Paxton, L. J.; Schaefer, R. K.; Nix, M.; Fountain, G. H.; Weiss, M.; Swartz, W. H.; Parker, C. L.; MacDonald, L.; Ihde, A. G.; Simpkins, S.; GAIA Team

    2011-12-01

    In this paper we describe the application of a proven methodology for modeling the complex social and economic interactions embodied in real-world decision making to water scarcity and water resources. We have developed a generalizable, extensible facility we call "GAIA" - Global Assimilation of Information for Action - and applied it to different problem sets. We describe the use of the "Green Country Model" and other gaming/simulation tools to address the impacts of climate and climate disruption issues at the intersection of science, economics, policy, and society. There is a long history in the Defense community of using what are known as strategic simulations or "wargames" to model the complex interactions between the environment, people, resources, infrastructure and the economy in a competitive environment. We describe in this paper, work that we have done on understanding how this heritage can be repurposed to help us explore how the complex interplay between climate disruption and our socio/political and economic structures will affect our future. Our focus here is on a fundamental and growing issue - water and water availability. We consider water and the role of "virtual water" in the system. Various "actors" are included in the simulations. While these simulations cannot definitively predict what will happen, they do illuminate non-linear feedbacks between, for example, treaty agreement, the environment, the economy, and the government. These simulations can be focused on the global, regional, or local environment. We note that these simulations are not "zero sum" games - there need not be a winner and a loser. They are, however, competitive influence games: they represent the tools that a nation, state, faction or group has at its disposal to influence policy (diplomacy), finances, industry (economy), infrastructure, information, etc to achieve their particular goals. As in the real world the problem is competitive - not everyone shares the same

  10. Frequency Domain Decomposition performed on the strain data obtained from the aluminium model of an offshore support structure

    NASA Astrophysics Data System (ADS)

    Mieloszyk, M.; Opoka, S.; Ostachowicz, W.

    2015-07-01

    This paper presents an application of Fibre Bragg Grating (FBG) sensors for Structural Health Monitoring (SHM) of offshore wind energy support structure model. The analysed structure is a tripod equipped with 16 FBG sensors. From a wide variety of Operational Modal Analysis (OMA) methods Frequency Domain Decomposition (FDD) technique is used in this paper under assumption that the input loading is similar to a white noise excitation. The FDD method can be applied using different sets of sensors, i.e. the one which contains all FBG sensors and the other set of sensors localised only on a particular tripod's leg. The cases considered during investigation were as follows: damaged and undamaged scenarios, different support conditions. The damage was simulated as an dismantled flange on an upper brace in one of the tripod legs. First the model was fixed to an antishaker table and investigated in the air under impulse excitations. Next the tripod was submerged into water basin in order to check the quality of the measurement set-up in different environmental condition. In this case the model was excited by regular waves.

  11. Peers' Perceived Support, Student Engagement in Academic Activities and Life Satisfaction: A Structural Equation Modeling Approach

    ERIC Educational Resources Information Center

    Hakimzadeh, Rezvan; Besharat, Mohammad-Ali; Khaleghinezhad, Seyed Ali; Ghorban Jahromi, Reza

    2016-01-01

    This study investigates the relationships among peers' perceived support, life satisfaction, and student engagement in academic activities. Three hundred and fifteen Iranian students (172 boys and 143 girls) who were studying in one suburb of Tehran participated in this study. All participants were asked to complete Peers' Perceived Support scale…

  12. Support Substructures: Support-Induced Part-Level Structural Representation.

    PubMed

    Huang, Shi-Sheng; Fu, Hongbo; Wei, Ling-Yu; Hu, Shi-Min

    2016-08-01

    In this work we explore a support-induced structural organization of object parts. We introduce the concept of support substructures, which are special subsets of object parts with support and stability. A bottom-up approach is proposed to identify such substructures in a support relation graph. We apply the derived high-level substructures to part-based shape reshuffling between models, resulting in nontrivial functionally plausible model variations that are difficult to achieve with symmetry-induced substructures by the state-of-the-art methods. We also show how to automatically or interactively turn a single input model to new functionally plausible shapes by structure rearrangement and synthesis, enabled by support substructures. To the best of our knowledge no single existing method has been designed for all these applications. PMID:26336128

  13. Aeroelastic Modeling of Offshore Turbines and Support Structures in Hurricane-Prone Regions (Poster)

    SciTech Connect

    Damiani, R.

    2014-03-01

    US offshore wind turbines (OWTs) will likely have to contend with hurricanes and the associated loading conditions. Current industry standards do not account for these design load cases (DLCs), thus a new approach is required to guarantee that the OWTs achieve an appropriate level of reliability. In this study, a sequentially coupled aero-hydro-servo-elastic modeling technique was used to address two design approaches: 1.) The ABS (American Bureau of Shipping) approach; and 2.) The Hazard Curve or API (American Petroleum Institute) approach. The former employs IEC partial load factors (PSFs) and 100-yr return-period (RP) metocean events. The latter allows setting PSFs and RP to a prescribed level of system reliability. The 500-yr RP robustness check (appearing in [2] and [3] upcoming editions) is a good indicator of the target reliability for L2 structures. CAE tools such as NREL's FAST and Bentley's' SACS (offshore analysis and design software) can be efficiently coupled to simulate system loads under hurricane DLCs. For this task, we augmented the latest FAST version (v. 8) to include tower aerodynamic drag that cannot be ignored in hurricane DLCs. In this project, a 6 MW turbine was simulated on a typical 4-legged jacket for a mid-Atlantic site. FAST-calculated tower base loads were fed to SACS at the interface level (transition piece); SACS added hydrodynamic and wind loads on the exposed substructure, and calculated mudline overturning moments, and member and joint utilization. Results show that CAE tools can be effectively used to compare design approaches for the design of OWTs in hurricane regions and to achieve a well-balanced design, where reliability levels and costs are optimized.

  14. Modeling of water absorption induced cracks in resin-based composite supported ceramic layer structures.

    PubMed

    Huang, Min; Thompson, V P; Rekow, E D; Soboyejo, W O

    2008-01-01

    Cracking patterns in the top ceramic layers of the modeled dental multilayers with polymer foundation are observed when they are immersed in water. This article developed a model to understand this cracking mechanism. When water diffuses into the polymer foundation of dental restorations, the foundation will expand; as a result, the stress will build up in the top ceramic layer because of the bending and stretching. A finite element model based on this mechanism is built to predict the stress build-up and the slow crack growth in the top ceramic layers during the water absorption. Our simulations show that the stress build-up by this mechanism is high enough to cause the cracking in the top ceramic layers and the cracking patterns predicted by our model are well consistent with those observed in experiments on glass/epoxy/polymer multilayers. The model is then used to discuss the life prediction of different dental ceramics. PMID:17497681

  15. Structural Modeling of Variables Related to Parental Support in Mexican Children's Perfomance on Reading and Writing

    ERIC Educational Resources Information Center

    Bazan-Ramirez, Aldo; Castellanos-Simons, Doris; Lopez-Valenzuela, Mercedes

    2010-01-01

    This paper aims at analysing the structural relationships among some latent and observed variables related to the assessment of written language performance in 139 fourth grade students of Elementary School selected from nine public schools of the northwest of Mexico. Questionnaires were also applied to the children's parents and teachers. The…

  16. Data models and diagnosis algorithms to support structural health monitoring system for buildings

    NASA Astrophysics Data System (ADS)

    Mita, Akira; Ogawa, Shuichi

    2009-03-01

    We have recently developed a prototype SHM system consisting of smart sensors, database and MATALB servers. In preceding efforts, we demonstrated the usefulness of analyzing and publishing the data on the web. However, the effective data management and automatic analysis had not been provided. In this study, the data model for easy and flexible data management and automatic configuration of the smart sensors are proposed and their feasibility is demonstrated. In addition, an automatic analysis tool based on ARX models is introduced for practical application. The prototype SHM system is in operation for more than two months without any troubles. To incorporate many needs from different stakeholders, we formed a consortium called K-SHM last year at Keio University. At present, 16 companies joined the consortium consisting of 11 construction companies, 3 large design firms, a sensor maker and a system integration company as members. The consortium will continue improving this system for real application.

  17. The Effects of Supervisors' Support and Mediating Factors on the Nurses' Job Performance Using Structural Equation Modeling: A Case Study.

    PubMed

    Ravangard, Ramin; Yasami, Shamim; Shokrpour, Nasrin; Sajjadnia, Zahra; Farhadi, Payam

    2015-01-01

    Nurses are the largest group and an important part of the providers in the health care systems that who a key role in hospitals. Any defect and deficiency in their work can result in irreversible outcomes. This study aimed to determine the effect of supervisors' support and mediating factors on the job performance (JOBPER) of 400 nurses working in the teaching hospitals affiliated to Shiraz University of Medical Sciences, using structural equation modeling. The results showed that the supervisor's support had a significant negative effect on work-family conflict (t = -2.57) and a positive effect on organizational commitment (t = 4.03); Work-family conflict had a significant positive effect on job stress (t = 11.24) and a negative effect on organizational commitment (t = -3.35) and JOBPER (t = -2.29). Family-work conflict had a positive effect on job stress (t = 4.48) and a negative effect on organizational commitment (t = -2.54). Finally, job stress had a negative effect (t = -3.30), and organizational commitment showed a positive effect (t = 5.96) on the studied nurses' JOBPER. According to the results, supervisor's support could influence JOBPER through reducing work-family conflict and increasing organizational commitment. Therefore, to improve the nurses' JOBPER in the hospitals, some strategies are recommended. PMID:26218002

  18. Structural Modeling of a Five-Meter Thin Film Inflatable Antenna/Concentrator With Rigidized Support Struts

    NASA Technical Reports Server (NTRS)

    Smalley, Kurt B.; Tinker, Michael L.

    2001-01-01

    Dynamic characterization of a non-rigidized thin film inflatable antenna/solar concentrator structure with rigidized composite support struts is described in detail. A two-step finite element modeling approach in MSC/NASTRAN is utilized, consisting of: (1) a nonlinear static pressurization procedure used to obtain the updated stiffness matrix, and (2) a modal "restart" eigen solution that uses the modified stiffness matrix. Unique problems encountered in modeling of this large 5-m lightweight inflatable are identified, including considerable difficulty in obtaining convergence in the nonlinear pressurization solution. It was found that the extremely thin polyimide film material (.001 in or I mil) presents tremendous problems in obtaining a converged solution when internal pressure loading is applied. It was concluded that the ratios of film thickness to other geometric dimensions such as torus cross-sectional and ring diameter and lenticular diameter are the critical parameters for convergence of the pressurization procedure. Comparison of finite element predictions for frequency and mode shapes with experimental results indicated reasonable agreement considering the complexity of the structure, the film-to-air interaction, and the nonlinear material properties of the film. It was also concluded that analysis should be done using different finite element to codes to determine if a more robust and stable solution can be obtained.

  19. DNA attachment to support structures

    DOEpatents

    Balhorn, Rodney L.; Barry, Christopher H.

    2002-01-01

    Microscopic beads or other structures are attached to nucleic acids (DNA) using a terminal transferase. The transferase adds labeled dideoxy nucleotide bases to the ends of linear strands of DNA. The labels, such as the antigens digoxigenin and biotin, bind to the antibody compounds or other appropriate complementary ligands, which are bound to the microscopic beads or other support structures. The method does not require the synthesis of a synthetic oligonucleotide probe. The method can be used to tag or label DNA even when the DNA has an unknown sequence, has blunt ends, or is a very large fragment (e.g., >500 kilobase pairs).

  20. Structural analysis of FAST reflector supporting system

    NASA Astrophysics Data System (ADS)

    Luo, Y. F.; Deng, C. G.; Li, G. Q.; He, Y. M.

    According to the deformation and movement requirements of the FAST reflector, a multi-purpose analysis, including the load-bearing behavior, deformation, construction costs of the reflector supporting structure and its model, is presented in this paper. The advantages and disadvantages of steel and aluminum alloy structures are also discussed and compared through detailed design calculations under load-bearing capacity and normal working conditions.

  1. A semi-structured MODFLOW-USG model to evaluate local water sources to wells for decision support

    USGS Publications Warehouse

    Feinstein, Daniel T.; Fienen, Michael N.; Reeves, Howard W.; Langevin, Christian D.

    2016-01-01

    In order to better represent the configuration of the stream network and simulate local groundwater-surface water interactions, a version of MODFLOW with refined spacing in the topmost layer was applied to a Lake Michigan Basin (LMB) regional groundwater-flow model developed by the U.S. Geological. Regional MODFLOW models commonly use coarse grids over large areas; this coarse spacing precludes model application to local management issues (e.g., surface-water depletion by wells) without recourse to labor-intensive inset models. Implementation of an unstructured formulation within the MODFLOW framework (MODFLOW-USG) allows application of regional models to address local problems. A “semi-structured” approach (uniform lateral spacing within layers, different lateral spacing among layers) was tested using the LMB regional model. The parent 20-layer model with uniform 5000-foot (1524-m) lateral spacing was converted to 4 layers with 500-foot (152-m) spacing in the top glacial (Quaternary) layer, where surface water features are located, overlying coarser resolution layers representing deeper deposits. This semi-structured version of the LMB model reproduces regional flow conditions, whereas the finer resolution in the top layer improves the accuracy of the simulated response of surface water to shallow wells. One application of the semi-structured LMB model is to provide statistical measures of the correlation between modeled inputs and the simulated amount of water that wells derive from local surface water. The relations identified in this paper serve as the basis for metamodels to predict (with uncertainty) surface-water depletion in response to shallow pumping within and potentially beyond the modeled area, see Fienen et al. (2015a).

  2. Community-oriented support and research structures

    NASA Astrophysics Data System (ADS)

    Attig, Norbert; Eickermann, Thomas; Gibbon, Paul; Lippert, Thomas

    2009-07-01

    Coordinated by the Partnership for Advanced Computing in Europe (PRACE) Europe is restructuring and strengthening its high-performance computing infrastructure with the aim to create a model HPC ecosystem. At the tip of the pyramid, up to six centres are envisaged that will operate systems of the highest performance class. The HPC Research Infrastructure (HPC-RI) will comprise European, national and regional centres. Science communities are integral partners, strong links will include Grid and Cloud users. The HPC-RI strives at providing scientists all over Europe, on the one hand, with unlimited and independent access to state-of-the-art computer resources in all performance classes and, on the other hand, with a world-class pan-European competence and support network. While the hardware-oriented buildup of the infrastructure is making progress, high-quality user support and software development in the upcoming era of unprecedented parallelism and exascale on the horizon have become the imminent challenges. This has been clearly recognized by the European Commission, who will issue calls for proposals to fund petascale software development in summer 2009. Although traditional support structures are well established in Europe's major supercomputing centres, it is questionable if these structures are able to meet the challenges of the future: in general, support structures are based on cross-disciplinary computer science and mathematics teams; disciplinary computational science support usually is given in an ad-hoc, project-oriented manner. In this paper, we describe our approach to establish a suitable support structure-Simulation Laboratories (SL). SLs are currently being established at the Jülich Supercomputing Centre of the Forschungszentrum Jülich (FZJ) and at the Steinbuch Centre for Computing (SCC) of the Karlsruhe Institute for Technology (KIT) in Germany. While SLs are community-oriented, i.e. each SL focusses on a specific community, they are structured

  3. Factor Structure and Longitudinal Measurement Invariance of the Demand Control Support Model: An Evidence from the Swedish Longitudinal Occupational Survey of Health (SLOSH)

    PubMed Central

    Chungkham, Holendro Singh; Ingre, Michael; Karasek, Robert; Westerlund, Hugo; Theorell, Töres

    2013-01-01

    Objectives To examine the factor structure and to evaluate the longitudinal measurement invariance of the demand-control-support questionnaire (DCSQ), using the Swedish Longitudinal Occupational Survey of Health (SLOSH). Methods A confirmatory factor analysis (CFA) and multi-group confirmatory factor analysis (MGCFA) models within the framework of structural equation modeling (SEM) have been used to examine the factor structure and invariance across time. Results Four factors: psychological demand, skill discretion, decision authority and social support, were confirmed by CFA at baseline, with the best fit obtained by removing the item repetitive work of skill discretion. A measurement error correlation (0.42) between work fast and work intensively for psychological demands was also detected. Acceptable composite reliability measures were obtained except for skill discretion (0.68). The invariance of the same factor structure was established, but caution in comparing mean levels of factors over time is warranted as lack of intercept invariance was evident. However, partial intercept invariance was established for work intensively. Conclusion Our findings indicate that skill discretion and decision authority represent two distinct constructs in the retained model. However removing the item repetitive work along with either work fast or work intensively would improve model fit. Care should also be taken while making comparisons in the constructs across time. Further research should investigate invariance across occupations or socio-economic classes. PMID:23950957

  4. Foil support structure for large electron guns

    SciTech Connect

    Brucker, J.P.; Rose, E.A.

    1993-08-01

    This paper describes a novel support structure for a vacuum diode used to pump a gaseous laser with an electron beam. Conventional support structures are designed to hold a foil flat and rigid. This new structure takes advantage of the significantly greater strength of metals in pure tension, utilizing curved shapes for both foil and support structure. The shape of the foil is comparable to the skin of a balloon, and the shape of the support structures is comparable to the cables of a suspension bridge. This design allows a significant reduction in foil thickness and support structure mass, resulting in a lower electron-beam loss between diode and laser gas. In addition, the foil is pre-formed in the support structure at pressures higher than operating pressure. Therefore, the foil is operated far from the yield point. Increased reliability is anticipated.

  5. Globin gene structure in a reptile supports the transpositional model for amniote α- and β-globin gene evolution.

    PubMed

    Patel, Vidushi S; Ezaz, Tariq; Deakin, Janine E; Graves, Jennifer A Marshall

    2010-12-01

    The haemoglobin protein, required for oxygen transportation in the body, is encoded by α- and β-globin genes that are arranged in clusters. The transpositional model for the evolution of distinct α-globin and β-globin clusters in amniotes is much simpler than the previously proposed whole genome duplication model. According to this model, all jawed vertebrates share one ancient region containing α- and β-globin genes and several flanking genes in the order MPG-C16orf35-(α-β)-GBY-LUC7L that has been conserved for more than 410 million years, whereas amniotes evolved a distinct β-globin cluster by insertion of a transposed β-globin gene from this ancient region into a cluster of olfactory receptors flanked by CCKBR and RRM1. It could not be determined whether this organisation is conserved in all amniotes because of the paucity of information from non-avian reptiles. To fill in this gap, we examined globin gene organisation in a squamate reptile, the Australian bearded dragon lizard, Pogona vitticeps (Agamidae). We report here that the α-globin cluster (HBK, HBA) is flanked by C16orf35 and GBY and is located on a pair of microchromosomes, whereas the β-globin cluster is flanked by RRM1 on the 3' end and is located on the long arm of chromosome 3. However, the CCKBR gene that flanks the β-globin cluster on the 5' end in other amniotes is located on the short arm of chromosome 5 in P. vitticeps, indicating that a chromosomal break between the β-globin cluster and CCKBR occurred at least in the agamid lineage. Our data from a reptile species provide further evidence to support the transpositional model for the evolution of β-globin gene cluster in amniotes. PMID:21116705

  6. Parsimonious rainfall-runoff model construction supported by time series processing and validation of hydrological extremes - Part 1: Step-wise model-structure identification and calibration approach

    NASA Astrophysics Data System (ADS)

    Willems, Patrick

    2014-03-01

    Common problems faced by rainfall-runoff modellers are data limitation, model overparameterization and related problems of parameter identifiability. Depending on the application, possible solutions to overcome these problems include the use of parsimonious conceptual models, avoid the use of a fixed pre-defined model conceptualization, but apply a “top-down” or “downward” method to allow the model structure to be adjusted or inferred from available data and field evidence. This paper presents a top-down procedure that starts from a generalized model structure framework that is adjusted in a case-specific parsimonious way. The model-structure building is done in a transparent, step-wise way, where separate parts of the model structure are identified and calibrated based on multiple and non-commensurable information derived from river flow series by means of a number of sequential time series processing tasks. These include separation of the high frequency (e.g., hourly, daily) river flow series into subflows, split of the series in approx. independent quick and slow flow hydrograph periods, and the extraction of independent peak and low flows. The model building and calibration account for the statistical assumptions and requirements on independency and homoscedasticity of the model residuals. Next to identification of the subflow recessions and related routing submodels, equations describing quick and slow runoff sub-responses and soil water storage are derived from the time series data. The method includes testing of the model performance for peak and low flow extremes.

  7. Application of 3D digital image correlation for development and validation of FEM model of self-supporting metal plates structures

    NASA Astrophysics Data System (ADS)

    Malowany, Krzysztof; Malesa, Marcin; Piekarczuk, Artur; Kujawińska, Małgorzata; Skrzypczak, Paweł; Wiech, Przemysław

    2016-04-01

    Many building structures due to complex geometry and nonlinear material properties are difficult to be analyzed with FEM methods. A good example is a self-supporting metal plates structure. Considering uncommon geometry and material characteristic of a metal plate (due to plastic deformations, cross section of a trough, a goffer pattern), the local loss of stability can occur in unexpected regions. Therefore, the hybrid experimental-numerical methodology of analysis and optimization of metal plates structures has been developed. The methodology is based on three steps of development and validation of a numerical model with utilization of Digital Image Correlation measurements. In each step, the measurements are performed in different environments, with different accuracies and different scales. In this paper, the results of analysis performed with Digital Image Correlation, that enabled development and validation of FEM model are presented. The performed modification of a measurement setup is also described.

  8. Rhode Island Model Evaluation & Support System: Support Professional. Edition II

    ERIC Educational Resources Information Center

    Rhode Island Department of Education, 2015

    2015-01-01

    Rhode Island educators believe that implementing a fair, accurate, and meaningful evaluation and support system for support professionals will help improve student outcomes. The primary purpose of the Rhode Island Model Support Professional Evaluation and Support System (Rhode Island Model) is to help all support professionals do their best work…

  9. Support Vector Training of Protein Alignment Models

    PubMed Central

    Joachims, Thorsten; Elber, Ron; Pillardy, Jaroslaw

    2008-01-01

    Abstract Sequence to structure alignment is an important step in homology modeling of protein structures. Incorporation of features such as secondary structure, solvent accessibility, or evolutionary information improve sequence to structure alignment accuracy, but conventional generative estimation techniques for alignment models impose independence assumptions that make these features difficult to include in a principled way. In this paper, we overcome this problem using a Support Vector Machine (SVM) method that provides a well-founded way of estimating complex alignment models with hundred of thousands of parameters. Furthermore, we show that the method can be trained using a variety of loss functions. In a rigorous empirical evaluation, the SVM algorithm outperforms the generative alignment method SSALN, a highly accurate generative alignment model that incorporates structural information. The alignment model learned by the SVM aligns 50% of the residues correctly and aligns over 70% of the residues within a shift of four positions. PMID:18707536

  10. Effects of Co-Worker and Supervisor Support on Job Stress and Presenteeism in an Aging Workforce: A Structural Equation Modelling Approach.

    PubMed

    Yang, Tianan; Shen, Yu-Ming; Zhu, Mingjing; Liu, Yuanling; Deng, Jianwei; Chen, Qian; See, Lai-Chu

    2016-01-01

    We examined the effects of co-worker and supervisor support on job stress and presenteeism in an aging workforce. Structural equation modelling was used to evaluate data from the 2010 wave of the Health and Retirement Survey in the United States (n = 1649). The level of presenteeism was low and the level of job stress was moderate among aging US workers. SEM revealed that co-worker support and supervisor support were strongly correlated (β = 0.67; p < 0.001). Job stress had a significant direct positive effect on presenteeism (β = 0.30; p < 0.001). Co-worker support had a significant direct negative effect on job stress (β = -0.10; p < 0.001) and presenteeism (β = -0.11; p < 0.001). Supervisor support had a significant direct negative effect on job stress (β = -0.40; p < 0.001) but not presenteeism. The findings suggest that presenteeism is reduced by increased respect and concern for employee stress at the workplace, by necessary support at work from colleagues and employers, and by the presence of comfortable interpersonal relationships among colleagues and between employers and employees. PMID:26703705

  11. Effects of Co-Worker and Supervisor Support on Job Stress and Presenteeism in an Aging Workforce: A Structural Equation Modelling Approach

    PubMed Central

    Yang, Tianan; Shen, Yu-Ming; Zhu, Mingjing; Liu, Yuanling; Deng, Jianwei; Chen, Qian; See, Lai-Chu

    2015-01-01

    We examined the effects of co-worker and supervisor support on job stress and presenteeism in an aging workforce. Structural equation modelling was used to evaluate data from the 2010 wave of the Health and Retirement Survey in the United States (n = 1649). The level of presenteeism was low and the level of job stress was moderate among aging US workers. SEM revealed that co-worker support and supervisor support were strongly correlated (β = 0.67; p < 0.001). Job stress had a significant direct positive effect on presenteeism (β = 0.30; p < 0.001). Co-worker support had a significant direct negative effect on job stress (β = −0.10; p < 0.001) and presenteeism (β = −0.11; p < 0.001). Supervisor support had a significant direct negative effect on job stress (β = −0.40; p < 0.001) but not presenteeism. The findings suggest that presenteeism is reduced by increased respect and concern for employee stress at the workplace, by necessary support at work from colleagues and employers, and by the presence of comfortable interpersonal relationships among colleagues and between employers and employees. PMID:26703705

  12. Dynamic structural disorder in supported nanoscale catalysts

    SciTech Connect

    Rehr, J. J.; Vila, F. D.

    2014-04-07

    We investigate the origin and physical effects of “dynamic structural disorder” (DSD) in supported nano-scale catalysts. DSD refers to the intrinsic fluctuating, inhomogeneous structure of such nano-scale systems. In contrast to bulk materials, nano-scale systems exhibit substantial fluctuations in structure, charge, temperature, and other quantities, as well as large surface effects. The DSD is driven largely by the stochastic librational motion of the center of mass and fluxional bonding at the nanoparticle surface due to thermal coupling with the substrate. Our approach for calculating and understanding DSD is based on a combination of real-time density functional theory/molecular dynamics simulations, transient coupled-oscillator models, and statistical mechanics. This approach treats thermal and dynamic effects over multiple time-scales, and includes bond-stretching and -bending vibrations, and transient tethering to the substrate at longer ps time-scales. Potential effects on the catalytic properties of these clusters are briefly explored. Model calculations of molecule-cluster interactions and molecular dissociation reaction paths are presented in which the reactant molecules are adsorbed on the surface of dynamically sampled clusters. This model suggests that DSD can affect both the prefactors and distribution of energy barriers in reaction rates, and thus can significantly affect catalytic activity at the nano-scale.

  13. Dynamic structural disorder in supported nanoscale catalysts.

    PubMed

    Rehr, J J; Vila, F D

    2014-04-01

    We investigate the origin and physical effects of "dynamic structural disorder" (DSD) in supported nano-scale catalysts. DSD refers to the intrinsic fluctuating, inhomogeneous structure of such nano-scale systems. In contrast to bulk materials, nano-scale systems exhibit substantial fluctuations in structure, charge, temperature, and other quantities, as well as large surface effects. The DSD is driven largely by the stochastic librational motion of the center of mass and fluxional bonding at the nanoparticle surface due to thermal coupling with the substrate. Our approach for calculating and understanding DSD is based on a combination of real-time density functional theory/molecular dynamics simulations, transient coupled-oscillator models, and statistical mechanics. This approach treats thermal and dynamic effects over multiple time-scales, and includes bond-stretching and -bending vibrations, and transient tethering to the substrate at longer ps time-scales. Potential effects on the catalytic properties of these clusters are briefly explored. Model calculations of molecule-cluster interactions and molecular dissociation reaction paths are presented in which the reactant molecules are adsorbed on the surface of dynamically sampled clusters. This model suggests that DSD can affect both the prefactors and distribution of energy barriers in reaction rates, and thus can significantly affect catalytic activity at the nano-scale. PMID:24712802

  14. Material Selection for Cryogenic Support Structures

    NASA Astrophysics Data System (ADS)

    Kramer, Erik; Kellaris, Nicholas; Daal, Miguel; Sadoulet, Bernard; Golwala, Sunil; Hollister, Matthew

    2014-09-01

    Design specifications for the support structures of low temperature instrumentation often call for low thermal conductivity between temperature stages, high stiffness, and specific load bearing capabilities. While overall geometric design plays an important role in both overall stiffness and heat conduction between stages, material selection can affect a structure's properties significantly. In this contribution, we suggest and compare several alternative materials to the current standard materials for building cryogenic support structures.

  15. Contributions of Parents' School Opinions and Reasons for Choice to Their Willingness To Support Catholic High Schools: A Structural Model.

    ERIC Educational Resources Information Center

    Bauch, Patricia A.; Gao, Hong

    A study was conducted to determine the association among variables representing parent and school demographics, parents' opinions of the school, their reasons for choosing it, and their willingness to support the school in various ways, including the level of tuition they would pay. Data were collected from a stratified sample of 10 high schools…

  16. Proceedings: Support-Structure Corrosion in Steam Generators

    SciTech Connect

    1983-01-01

    This report documents an EPRI workshop held in Boston in May 1982 to discuss support structure corrosion in steam generators. Designed to present information on available materials and designs for support structures and to determine utility needs, the workshop covered crevice corrosion rates for alloy steels and carbon steel, results from examinations of support plate segments removed from steam generators, and models for corrosion and salt hideout in crevices.

  17. Influence of backup bearings and support structure dynamics on the behavior of rotors with active supports

    NASA Technical Reports Server (NTRS)

    Flowers, George T.

    1995-01-01

    This semiannual status report lists specific accomplishments made on the research of the influence of backup bearings and support structure dynamics on the behavior of rotors with active supports. Papers have been presented representing work done on the T-501 engine model; an experimental/simulation study of auxiliary bearing rotordynamics; and a description of a rotordynamical model for a magnetic bearing supported rotor system, including auxiliary bearing effects. A finite element model for a foil bearing has been developed. Additional studies of rotor/bearing/housing dynamics are currently being performed as are studies of the effects of sideloading on auxiliary bearing rotordynamics using the magnetic bearing supported rotor model.

  18. Pactruss support structure for precision segmented reflectors

    NASA Technical Reports Server (NTRS)

    Hedgepeth, John M.

    1989-01-01

    The application of the Pactruss deployable structure to the support of large paraboloidal reflectors of very high precision was studied. The Pactruss concept, originally conceived for the Space Station truss, is shown to be suitable for use in a triangular arrangement to support a reflector surface composed of hexagonal reflector panels. A hybrid of Pactruss structural and deployable single-fold beams is shown to accommodate a center body. A minor alteration in the geometry is in order to avoid lockup during deployment. To assess the capability of the hybrid Pactruss structure, an example truss supporting a full-scale (20 meter diameter) infrared telescope was analyzed for static and dynamic performance. A truss structure weighing 800 kilograms gave adequate support to a reflector surface weighing 3,000 kilograms.

  19. 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.

  20. Disk-and-washer structure with biperiodic support

    NASA Astrophysics Data System (ADS)

    Iwashita, Y.

    1994-08-01

    The disk-and-washer (DAW) linac structure with particular biperiodic washer-support geometries was studied. RF measurements on the DAW model cavities with 2-T and 4-T support configurations were carried out, and the results were compared with SUPERFISH and MAFIA calculation results. The results show that the biperiodic structure can overcome the mode overlapping problem. The support power losses caused by the electric field in addition to the magnetic field are studied. For a β = 1.0, 1300 MHz accelerating structure, the calculated shunt impedance of 71 MΩ/m is expected with a biperiodic 2-L structure which is a variant from the biperiodic 4-T configuration.

  1. Federal and State Structures to Support Financing Utility-Scale Solar Projects and the Business Models Designed to Utilize Them

    SciTech Connect

    Mendelsohn, M.; Kreycik, C.

    2012-04-01

    Utility-scale solar projects have grown rapidly in number and size over the last few years, driven in part by strong renewable portfolio standards (RPS) and federal incentives designed to stimulate investment in renewable energy technologies. This report provides an overview of such policies, as well as the project financial structures they enable, based on industry literature, publicly available data, and questionnaires conducted by the National Renewable Energy Laboratory (NREL).

  2. Structural support bracket for gas flow path

    DOEpatents

    None

    2016-08-02

    A structural support system is provided in a can annular gas turbine engine having an arrangement including a plurality of integrated exit pieces (IEPs) forming an annular chamber for delivering gases from a plurality of combustors to a first row of turbine blades. A bracket structure is connected between an IEP and an inner support structure on the engine. The bracket structure includes an axial bracket member attached to an IEP and extending axially in a forward direction. A transverse bracket member has an end attached to the inner support structure and extends circumferentially to a connection with a forward end of the axial bracket member. The transverse bracket member provides a fixed radial position for the forward end of the axial bracket member and is flexible in the axial direction to permit axial movement of the axial bracket member.

  3. Organizational Structures that Support Internal Program Evaluation

    ERIC Educational Resources Information Center

    Lambur, Michael T.

    2008-01-01

    This chapter explores how the structure of large complex organizations such as Cooperative Extension affects their ability to support internal evaluation of their programs and activities. Following a literature review of organizational structure and its relation to internal evaluation capacity, the chapter presents the results of interviews with…

  4. A case of strong metal-support interactions: combining advanced microscopy and model systems to elucidate the atomic structure of interfaces.

    PubMed

    Willinger, Marc G; Zhang, Wei; Bondarchuk, Oleksandr; Shaikhutdinov, Shamil; Freund, Hans-Joachim; Schlögl, Robert

    2014-06-01

    A symbiosis of advanced scanning probe and electron microscopy and a well-defined model system may provide a detailed picture of interfaces on nanostructured catalytic systems. This was demonstrated for Pt nanoparticles supported on iron oxide thin films which undergo encapsulation by supporting oxide as a result of strong metal-support interactions. PMID:24840397

  5. Turbine nozzle/nozzle support structure

    DOEpatents

    Boyd, Gary L.; Shaffer, James E.

    1995-01-01

    An axial flow turbine's nozzle/nozzle support structure having a cantilevered nozzle outer structure including an outer shroud and airfoil vanes extending radially inwardly therefrom, an inner shroud radially adjacent the inner end of the airfoil vanes and cooperatively disposed relative to the outer shroud to provide an annular fluid flow path, an inner and an outer support ring respectively arranged radially inside the inner shroud and axially adjacent a portion of the outer shroud, and pins extending through such portion and into the outer support ring. The inner support ring or inner shroud has a groove therein bounded by end walls for receiving and being axially abuttable with a locating projection from the adjacent airfoil vane, inner shroud, or inner support ring. The nozzle outer structure may comprise segments each of which has a single protrusion which is axially engageable with the outer support ring or, alternatively, a first and second protrusion which are arcuately and axially separated and which include axial openings therein whereby first and second protrusions on respective, arcuately adjacent nozzle segments have axial openings therein which are alignable with connector openings in the outer support ring and within each of such aligned openings a pin is receivable. The inner shroud may, likewise, comprise segments which, when assembled in operating configuration, have a 360 degree expanse.

  6. Turbine nozzle/nozzle support structure

    DOEpatents

    Boyd, Gary L.; Shaffer, James E.

    1996-01-01

    An axial flow turbine's nozzle/nozzle support structure having a cantilevered nozzle outer structure including an outer shroud and airfoil vanes extending radially inwardly therefrom, an inner shroud radially adjacent the inner end of the airfoil vanes and cooperatively disposed relative to the outer shroud to provide an annular fluid flow path, an inner and an outer support ring respectively arranged radially inside the inner shroud and axially adjacent a portion of the outer shroud, and pins extending through such portion and into the outer support ring. The inner support ring or inner shroud has a groove therein bounded by end walls for receiving and being axially abuttable with a locating projection from the adjacent airfoil vane, inner shroud, or inner support ring. The nozzle outer structure may comprise segments each of which has a single protrusion which is axially engageable with the outer support ring or, alternatively, a first and second protrusion which are arcuately and axially separated and which include axial openings therein whereby first and second protrusions on respective, arcuately adjacent nozzle segments have axial openings therein which are alignable with connector openings in the outer support ring and within each of such aligned openings a pin is receivable. The inner shroud may, likewise, comprise segments which, when assembled in operating configuration, have a 360 degree expanse.

  7. Turbine nozzle/nozzle support structure

    DOEpatents

    Boyd, Gary L.; Shaffer, James E.

    1997-01-01

    An axial flow turbine's nozzle/nozzle support structure having a cantilevered nozzle outer structure including an outer shroud and airfoil vanes extending radially inwardly therefrom, an inner shroud radially adjacent the inner end of the airfoil vanes and cooperatively disposed relative to the outer shroud to provide an annular fluid flow path, an inner and an outer support ring respectively arranged radially inside the inner shroud and axially adjacent a portion of the outer shroud, and pins extending through such portion and into the outer support ring. The inner support ring or inner shroud has a groove therein bounded by end walls for receiving and being axially abuttable with a locating projection from the adjacent airfoil vane, inner shroud, or inner support ring. The nozzle outer structure may comprise segments each of which has a single protrusion which is axially engageable with the outer support ring or, alternatively, a first and second protrusion which are arcuately and axially separated and which include axial openings therein whereby first and second protrusions on respective, arcuately adjacent nozzle segments have axial openings therein which are alignable with connector openings in the outer support ring and within each of such aligned openings a pin is receivable. The inner shroud may, likewise, comprise segments which, when assembled in operating configuration, have a 360 degree expanse.

  8. Turbine nozzle/nozzle support structure

    DOEpatents

    Boyd, G.L.; Shaffer, J.E.

    1997-01-07

    An axial flow turbine`s nozzle/nozzle support structure is described having a cantilevered nozzle outer structure including an outer shroud and airfoil vanes extending radially inwardly therefrom, an inner shroud radially adjacent the inner end of the airfoil vanes and cooperatively disposed relative to the outer shroud to provide an annular fluid flow path, an inner and an outer support ring respectively arranged radially inside the inner shroud and axially adjacent a portion of the outer shroud, and pins extending through such portion and into the outer support ring. The inner support ring or inner shroud has a groove therein bounded by end walls for receiving and being axially abuttable with a locating projection from the adjacent airfoil vane, inner shroud, or inner support ring. The nozzle outer structure may comprise segments each of which has a single protrusion which is axially engageable with the outer support ring or, alternatively, a first and second protrusion which are arcuately and axially separated and which include axial openings therein whereby first and second protrusions on respective, arcuately adjacent nozzle segments have axial openings therein which are alignable with connector openings in the outer support ring and within each of such aligned openings a pin is receivable. The inner shroud may, likewise, comprise segments which, when assembled in operating configuration, have a 360 degree expanse. 6 figs.

  9. Turbine nozzle/nozzle support structure

    DOEpatents

    Boyd, G.L.; Shaffer, J.E.

    1995-08-15

    An axial flow turbine`s nozzle/nozzle support structure is described having a cantilevered nozzle outer structure including an outer shroud and airfoil vanes extending radially inwardly therefrom, an inner shroud radially adjacent the inner end of the airfoil vanes and cooperatively disposed relative to the outer shroud to provide an annular fluid flow path, an inner and an outer support ring respectively arranged radially inside the inner shroud and axially adjacent a portion of the outer shroud, and pins extending through such portion and into the outer support ring. The inner support ring or inner shroud has a groove therein bounded by end walls for receiving and being axially abuttable with a locating projection from the adjacent airfoil vane, inner shroud, or inner support ring. The nozzle outer structure may comprise segments each of which has a single protrusion which is axially engageable with the outer support ring or, alternatively, a first and second protrusion which are arcuately and axially separated and which include axial openings therein whereby first and second protrusions on respective, arcuately adjacent nozzle segments have axial openings therein which are alignable with connector openings in the outer support ring and within each of such aligned openings a pin is receivable. The inner shroud may, likewise, comprise segments which, when assembled in operating configuration, have a 360 degree expanse. 6 figs.

  10. Turbine nozzle/nozzle support structure

    DOEpatents

    Boyd, G.L.; Shaffer, J.E.

    1996-09-10

    An axial flow turbine`s nozzle/nozzle support structure is described having a cantilevered nozzle outer structure including an outer shroud and airfoil vanes extending radially inwardly therefrom, an inner shroud radially adjacent the inner end of the airfoil vanes and cooperatively disposed relative to the outer shroud to provide an annular fluid flow path, an inner and an outer support ring respectively arranged radially inside the inner shroud and axially adjacent a portion of the outer shroud, and pins extending through such portion and into the outer support ring. The inner support ring or inner shroud has a groove therein bounded by end walls for receiving and being axially abuttable with a locating projection from the adjacent airfoil vane, inner shroud, or inner support ring. The nozzle outer structure may comprise segments each of which has a single protrusion which is axially engageable with the outer support ring or, alternatively, a first and second protrusion which are arcuately and axially separated and which include axial openings therein whereby first and second protrusions on respective, arcuately adjacent nozzle segments have axial openings therein which are alignable with connector openings in the outer support ring and within each of such aligned openings a pin is receivable. The inner shroud may, likewise, comprise segments which, when assembled in operating configuration, have a 360 degree expanse. 6 figs.

  11. Oscillating water column structural model

    SciTech Connect

    Copeland, Guild; Bull, Diana L; Jepsen, Richard Alan; Gordon, Margaret Ellen

    2014-09-01

    An oscillating water column (OWC) wave energy converter is a structure with an opening to the ocean below the free surface, i.e. a structure with a moonpool. Two structural models for a non-axisymmetric terminator design OWC, the Backward Bent Duct Buoy (BBDB) are discussed in this report. The results of this structural model design study are intended to inform experiments and modeling underway in support of the U.S. Department of Energy (DOE) initiated Reference Model Project (RMP). A detailed design developed by Re Vision Consulting used stiffeners and girders to stabilize the structure against the hydrostatic loads experienced by a BBDB device. Additional support plates were added to this structure to account for loads arising from the mooring line attachment points. A simplified structure was designed in a modular fashion. This simplified design allows easy alterations to the buoyancy chambers and uncomplicated analysis of resulting changes in buoyancy.

  12. Support structures for large infrared telescopes

    NASA Technical Reports Server (NTRS)

    Hedgepeth, J. M.

    1984-01-01

    An infrared telescope requires an accuracy of its reflecting surfaces of less than a micrometer. Future missions may require such accuracy from telescopes that are 20 meters or larger in diameter. The structure for supporting such a telescope will most probably take the form of a deep truss. Various approaches for constructing the primary mirror in space are illustrated. One that employs automated deployment of interconnected reflector-structure modules was described in detail. Estimates were made of the precision obtainable with properly configured truss structures and the required ability of active control systems for achieving the desired accuracy.

  13. Integrated support structure for GASCAN 2

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The focus of the Worcester Polytechnic Institute (WPI) Advanced Space Design Program was the preliminary design of the Integrated Support Structure for GASCAN II, a Get Away Special canister donated by the MITRE Corporation. Two teams of three students each worked on the support structure. There was a structural design team and a thermal design team. The structure will carry three experiments also undergoing preliminary design this year, the mu-gravity Ignition Experiment, the Rotational Flow in Low Gravity Experiment, and the Ionospheric Properties and Propagation Experiment. The structural design team was responsible for the layout of the GASCAN and the preliminary design of the structure itself. They produced the physical interface specifications defining the baseline weights and volumes for the equipment and produced layout drawings of the system. The team produced static and modal finite element analysis of the structure using ANSYS. The thermal design team was responsible for the power and timing requirements of the payload and for the identification and preliminary analysis of potential thermal problems. The team produced the power, timing, and energy interface specifications and assisted in the development of the specification of the battery pack. The thermal parameters of each experiment were cataloged and the experiments were subjected to worst case heat transfer scenarios.

  14. From Structural Chaos to a Model of Consumer Support: Understanding the Roles of Structure and Agency in Mental Health Recovery for the Formerly Homeless

    PubMed Central

    Watson, Dennis P.

    2012-01-01

    Current understandings of the effect that mental health services on consumers’ daily lives are still heavily informed by research conducted during the era of institutional treatment. This is problematic considering that changes to mental health care have shifted the locus of treatment to community settings for the majority of those living with serious and persistent mental illness (SPMI). With this shift there has been a greater focus on consumer-centered recovery in mental health care. In this paper I seek to develop a deeper understanding of the effect that the organization of mental health services offered in community settings has on the recovery process. I do this by presenting findings from the analysis of focus group and interview data collected from research informants (consumers and staff) at four Housing First programs located in a large Midwestern city. Housing First is based in a human rights approach to services that has been demonstrated to be more successful at housing chronically homeless consumers with dual diagnoses than traditional approaches to housing. My findings highlight the importance of understanding the connection that exists between social structure and personal agency and the recovery process. PMID:23275760

  15. Group decision support using Toulmin argument structures

    SciTech Connect

    Janssen, T. |; Sage, A.P.

    1996-12-31

    This paper addresses the need for sound science, technology, and management assessment relative to environmental policy decision making through an approach that involves a logical structure for evidence, a framed decision-making process, and an environment that encourages group participation. Toulmin-based logic possesses these characteristics and is used as the basis for development of a group decision support system. This system can support several user groups, such as pesticide policy-making experts, who can use the support system to state arguments for or against an important policy issue, and pest management experts, who can use the system to assist in identifying and evaluating alternatives for controlling pests on agricultural commodities. The resulting decision support system assists in improving the clarity of the lines of reasoning used in specific situations; the warrants, grounds, and backings that are used to support claims and specific lines of reasoning; and the contradictions, rebuttals, and arguments surrounding each step in the reasoning process associated with evaluating a claim or counterclaim. Experts and decisions makers with differing views can better understand each other`s thought processes. The net effect is enhanced communications and understanding of the whole picture and, in many cases, consensus on decisions to be taken.

  16. Regularized Structural Equation Modeling

    PubMed Central

    Jacobucci, Ross; Grimm, Kevin J.; McArdle, John J.

    2016-01-01

    A new method is proposed that extends the use of regularization in both lasso and ridge regression to structural equation models. The method is termed regularized structural equation modeling (RegSEM). RegSEM penalizes specific parameters in structural equation models, with the goal of creating easier to understand and simpler models. Although regularization has gained wide adoption in regression, very little has transferred to models with latent variables. By adding penalties to specific parameters in a structural equation model, researchers have a high level of flexibility in reducing model complexity, overcoming poor fitting models, and the creation of models that are more likely to generalize to new samples. The proposed method was evaluated through a simulation study, two illustrative examples involving a measurement model, and one empirical example involving the structural part of the model to demonstrate RegSEM’s utility. PMID:27398019

  17. Modeling and control design of a wind tunnel model support

    NASA Technical Reports Server (NTRS)

    Howe, David A.

    1990-01-01

    The 12-Foot Pressure Wind Tunnel at Ames Research Center is being restored. A major part of the restoration is the complete redesign of the aircraft model supports and their associated control systems. An accurate trajectory control servo system capable of positioning a model (with no measurable overshoot) is needed. Extremely small errors in scaled-model pitch angle can increase airline fuel costs for the final aircraft configuration by millions of dollars. In order to make a mechanism sufficiently accurate in pitch, a detailed structural and control-system model must be created and then simulated on a digital computer. The model must contain linear representations of the mechanical system, including masses, springs, and damping in order to determine system modes. Electrical components, both analog and digital, linear and nonlinear must also be simulated. The model of the entire closed-loop system must then be tuned to control the modes of the flexible model-support structure. The development of a system model, the control modal analysis, and the control-system design are discussed.

  18. Modelling and Decision Support of Clinical Pathways

    NASA Astrophysics Data System (ADS)

    Gabriel, Roland; Lux, Thomas

    The German health care market is under a rapid rate of change, forcing especially hospitals to provide high-quality services at low costs. Appropriate measures for more effective and efficient service provision are process orientation and decision support by information technology of clinical pathway of a patient. The essential requirements are adequate modelling of clinical pathways as well as usage of adequate systems, which are capable of assisting the complete path of a patient within a hospital, and preferably also outside of it, in a digital way. To fulfil these specifications the authors present a suitable concept, which meets the challenges of well-structured clinical pathways as well as rather poorly structured diagnostic and therapeutic decisions, by interplay of process-oriented and knowledge-based hospital information systems.

  19. Mathematical Model Development and Simulation Support

    NASA Technical Reports Server (NTRS)

    Francis, Ronald C.; Tobbe, Patrick A.

    2000-01-01

    This report summarizes the work performed in support of the Contact Dynamics 6DOF Facility and the Flight Robotics Lab at NASA/ MSFC in the areas of Mathematical Model Development and Simulation Support.

  20. Tethered and Polymer Supported Bilayer Lipid Membranes: Structure and Function

    PubMed Central

    Andersson, Jakob; Köper, Ingo

    2016-01-01

    Solid supported bilayer lipid membranes are model systems to mimic natural cell membranes in order to understand structural and functional properties of such systems. The use of a model system allows for the use of a wide variety of analytical tools including atomic force microscopy, impedance spectroscopy, neutron reflectometry, and surface plasmon resonance spectroscopy. Among the large number of different types of model membranes polymer-supported and tethered lipid bilayers have been shown to be versatile and useful systems. Both systems consist of a lipid bilayer, which is de-coupled from an underlying support by a spacer cushion. Both systems will be reviewed, with an emphasis on the effect that the spacer moiety has on the bilayer properties. PMID:27249006

  1. Tethered and Polymer Supported Bilayer Lipid Membranes: Structure and Function.

    PubMed

    Andersson, Jakob; Köper, Ingo

    2016-01-01

    Solid supported bilayer lipid membranes are model systems to mimic natural cell membranes in order to understand structural and functional properties of such systems. The use of a model system allows for the use of a wide variety of analytical tools including atomic force microscopy, impedance spectroscopy, neutron reflectometry, and surface plasmon resonance spectroscopy. Among the large number of different types of model membranes polymer-supported and tethered lipid bilayers have been shown to be versatile and useful systems. Both systems consist of a lipid bilayer, which is de-coupled from an underlying support by a spacer cushion. Both systems will be reviewed, with an emphasis on the effect that the spacer moiety has on the bilayer properties. PMID:27249006

  2. Versatile Support For Electromagnetic-Test Model

    NASA Technical Reports Server (NTRS)

    Wood, Richard M.; Ford, Eddie D.

    1994-01-01

    Supporting apparatus holds model for measurements of electromagnetic properties. Includes rigid swept strut, on end of which model oriented over range of angles. Designed to interfere minimally with electromagnetic measurements.

  3. Physics modeling support contract: Final report

    SciTech Connect

    Not Available

    1987-09-30

    This document is the final report for the Physics Modeling Support contract between TRW, Inc. and the Lawrence Livermore National Laboratory for fiscal year 1987. It consists of following projects: TIBER physics modeling and systems code development; advanced blanket modeling task; time dependent modeling; and free electron maser for TIBER II.

  4. Mathematical Modeling Of Life-Support Systems

    NASA Technical Reports Server (NTRS)

    Seshan, Panchalam K.; Ganapathi, Balasubramanian; Jan, Darrell L.; Ferrall, Joseph F.; Rohatgi, Naresh K.

    1994-01-01

    Generic hierarchical model of life-support system developed to facilitate comparisons of options in design of system. Model represents combinations of interdependent subsystems supporting microbes, plants, fish, and land animals (including humans). Generic model enables rapid configuration of variety of specific life support component models for tradeoff studies culminating in single system design. Enables rapid evaluation of effects of substituting alternate technologies and even entire groups of technologies and subsystems. Used to synthesize and analyze life-support systems ranging from relatively simple, nonregenerative units like aquariums to complex closed-loop systems aboard submarines or spacecraft. Model, called Generic Modular Flow Schematic (GMFS), coded in such chemical-process-simulation languages as Aspen Plus and expressed as three-dimensional spreadsheet.

  5. SPAR Model Structural Efficiencies

    SciTech Connect

    John Schroeder; Dan Henry

    2013-04-01

    The Nuclear Regulatory Commission (NRC) and the Electric Power Research Institute (EPRI) are supporting initiatives aimed at improving the quality of probabilistic risk assessments (PRAs). Included in these initiatives are the resolution of key technical issues that are have been judged to have the most significant influence on the baseline core damage frequency of the NRC’s Standardized Plant Analysis Risk (SPAR) models and licensee PRA models. Previous work addressed issues associated with support system initiating event analysis and loss of off-site power/station blackout analysis. The key technical issues were: • Development of a standard methodology and implementation of support system initiating events • Treatment of loss of offsite power • Development of standard approach for emergency core cooling following containment failure Some of the related issues were not fully resolved. This project continues the effort to resolve outstanding issues. The work scope was intended to include substantial collaboration with EPRI; however, EPRI has had other higher priority initiatives to support. Therefore this project has addressed SPAR modeling issues. The issues addressed are • SPAR model transparency • Common cause failure modeling deficiencies and approaches • Ac and dc modeling deficiencies and approaches • Instrumentation and control system modeling deficiencies and approaches

  6. Structural Model of Eumelanin

    NASA Astrophysics Data System (ADS)

    Kaxiras, Efthimios; Tsolakidis, Argyrios; Zonios, George; Meng, Sheng

    2006-11-01

    Melanin is a ubiquitous pigment in living organisms with multiple important functions, yet its structure is not well understood. We propose a structural model for eumelanin protomolecules, consisting of 4 or 5 of the basic molecular units (hydroquinone, indolequinone, and its tautomers), in arrangements that contain an inner porphyrin ring. We use time-dependent density functional theory to calculate the optical absorption spectrum of the structural model, which reproduces convincingly the main features of the experimental spectrum of eumelanin. Our model also reproduces accurately other important properties of eumelanin, including x-ray scattering data, its ability to capture and release metal ions, and the characteristic size of the protomolecules.

  7. Parallel software support for computational structural mechanics

    NASA Technical Reports Server (NTRS)

    Jordan, Harry F.

    1987-01-01

    The application of the parallel programming methodology known as the Force was conducted. Two application issues were addressed. The first involves the efficiency of the implementation and its completeness in terms of satisfying the needs of other researchers implementing parallel algorithms. Support for, and interaction with, other Computational Structural Mechanics (CSM) researchers using the Force was the main issue, but some independent investigation of the Barrier construct, which is extremely important to overall performance, was also undertaken. Another efficiency issue which was addressed was that of relaxing the strong synchronization condition imposed on the self-scheduled parallel DO loop. The Force was extended by the addition of logical conditions to the cases of a parallel case construct and by the inclusion of a self-scheduled version of this construct. The second issue involved applying the Force to the parallelization of finite element codes such as those found in the NICE/SPAR testbed system. One of the more difficult problems encountered is the determination of what information in COMMON blocks is actually used outside of a subroutine and when a subroutine uses a COMMON block merely as scratch storage for internal temporary results.

  8. The Entrepreneurial Model of Supported Employment.

    ERIC Educational Resources Information Center

    Markve, Robert; And Others

    1992-01-01

    Existing models of supported employment (individual placement, mobile crew, enclave, and benchwork models) have limited utility in rural areas. The Black Hills Special Services Cooperative (Sturgis, South Dakota) developed an entrepreneurial model that addresses the lack of rural employers and transportation problems by creating new businesses…

  9. Regolith-structure modeling

    NASA Technical Reports Server (NTRS)

    Ko, Hon-Yim; Sture, Stein

    1991-01-01

    shielding for habitation and workspace. The habitat module is treated as a rigid cylindrical tube with a smooth exterior. By making the cylinder rigid, a complex interaction problem is reduced to a situation where we can consider the support regolith and the shielding regolith as behaving independently of the structural properties of the cylindrical structure. Medium-dense lunar simulant was placed around a scaled model of the habitat module to provide a radiation shield. This embankment-type shield was constructed in relatively thin but fine layers by compacting, by mechanical vibratory means, layer upon layer of simulant placed adjacent to the horizontally-aligned cylinder. The slope angles were constructed at 55 degrees. The model described above was studied in a geotechnical centrifuge, which allows for the scaling of model dimensions to prototype dimensions by increasing the acceleration of gravity on the model. The deformation response can be scaled up to prototype dimensions to provide an assessment of the deformation patterns of the lunar structure. The actual process of local and/or global growth of instabilities or skip planes can also be observed.

  10. Optimized Heat Interception for Cryogen Tank Support Structure

    NASA Technical Reports Server (NTRS)

    Canavan, E. R.; Miller, F. K.

    2007-01-01

    We consider means for using the cooling available in boil-off gas to intercept heat conducted through the support structure of a cryogen tank. A one-dimensional model of the structure coupled to a gas stream gives an analytical expression for heat leak in terms of flow rate for temperature independent properties and laminar flow. A numerical model has been developed for heat transfer on a thin cylindrical tube with an attached vent line. The model is used to determine the vent path layout that will minimize heat flow into the cryogen tank. The results are useful for a number of applications, but the one of interest in this study is the minimization of the boil-off in large cryopropellant tanks in low Earth and low lunar orbit.

  11. Structural Equation Model Trees

    ERIC Educational Resources Information Center

    Brandmaier, Andreas M.; von Oertzen, Timo; McArdle, John J.; Lindenberger, Ulman

    2013-01-01

    In the behavioral and social sciences, structural equation models (SEMs) have become widely accepted as a modeling tool for the relation between latent and observed variables. SEMs can be seen as a unification of several multivariate analysis techniques. SEM Trees combine the strengths of SEMs and the decision tree paradigm by building tree…

  12. Structural Equation Model Trees

    PubMed Central

    Brandmaier, Andreas M.; von Oertzen, Timo; McArdle, John J.; Lindenberger, Ulman

    2015-01-01

    In the behavioral and social sciences, structural equation models (SEMs) have become widely accepted as a modeling tool for the relation between latent and observed variables. SEMs can be seen as a unification of several multivariate analysis techniques. SEM Trees combine the strengths of SEMs and the decision tree paradigm by building tree structures that separate a data set recursively into subsets with significantly different parameter estimates in a SEM. SEM Trees provide means for finding covariates and covariate interactions that predict differences in structural parameters in observed as well as in latent space and facilitate theory-guided exploration of empirical data. We describe the methodology, discuss theoretical and practical implications, and demonstrate applications to a factor model and a linear growth curve model. PMID:22984789

  13. Modelling ionospheric density structures

    NASA Technical Reports Server (NTRS)

    Schunk, R. W.; Sojka, J. J.

    1989-01-01

    Large-scale density structures are a common feature in the high-latitude ionsphere. The structures were observed in the dayside cusp, polar cap, and nocturnal auroral region over a range of altitudes, including the E-region, F-region and topside ionosphere. The origins, lifetimes and transport characteristics of large-scale density structures were studied with the aid of a three-dimensional, time-dependent ionospheric model. Blob creation due to particle precipitation, the effect that structured electric fields have on the ionosphere, and the lifetimes and transport characteristics of density structures for different seasonal, solar cycle, and interplanetary magnetic field (IMF) conditions were studied. The main conclusions drawn are: (1) the observed precipitation energy fluxes are sufficient for blob creation if the plasma is exposed to the precipitation for 5 to 10 minutes; (2) structured electric fields produce structured electron densities, ion temperatures, and ion composition; (3) the lifetime of an F-region density structure depends on several factors, including the initial location where it was formed, the magnitude of the perturbation, season, solar cycle and IMF; and (4) depending on the IMF, horizontal plasma convection can cause an initial structure to break up into multiple structures of various sizes, remain as a single distorted structure, or become stretched into elongated segments.

  14. Spring structure for a thermionic converter emitter support arrangement

    DOEpatents

    Allen, D.T.

    1992-03-17

    A support is provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs. 7 figs.

  15. Spring structure for a thermionic converter emitter support arrangement

    DOEpatents

    Allen, Daniel T.

    1992-01-01

    A support is provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housing, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

  16. The Structure and Validity of the Multidimensional Social Support Questionnaire

    ERIC Educational Resources Information Center

    Hardesty, Patrick H.; Richardson, George B.

    2012-01-01

    The factor structure and concurrent validity of the Multidimensional Social Support Questionnaire, a brief measure of perceived social support for use with adolescents, was examined. Findings suggest that four dimensions of perceived social support may yield more information than assessments of the unitary construct of support. (Contains 8 tables…

  17. Supporting Structures for Flat Solar-Cell Arrays

    NASA Technical Reports Server (NTRS)

    Wilson, A. H.

    1986-01-01

    Strong supporting structures for flat solar photovoltaic arrays built with such commonly available materials as wood and galvanized steel sheet. Structures resist expected static loads from snow and ice as well as dynamic loads from winds and even Earthquake vibrations. Supporting structure uses inexpensive materials. Parts prefabricated to minimize assembly work in field.

  18. Operations and support cost modeling of conceptual space vehicles

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles

    1994-01-01

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

  19. Generalized Multilevel Structural Equation Modeling

    ERIC Educational Resources Information Center

    Rabe-Hesketh, Sophia; Skrondal, Anders; Pickles, Andrew

    2004-01-01

    A unifying framework for generalized multilevel structural equation modeling is introduced. The models in the framework, called generalized linear latent and mixed models (GLLAMM), combine features of generalized linear mixed models (GLMM) and structural equation models (SEM) and consist of a response model and a structural model for the latent…

  20. A support structure for biomimetic applications

    NASA Astrophysics Data System (ADS)

    Vogel, J.; Perry, M.; Hansen, J. S.; Bolinger, P.-Y.; Nielsen, C. H.; Geschke, O.

    2009-02-01

    Water filtration on the basis of aquaporin molecules incorporated in an artificial lipid bilayer requires a microporous support membrane. We describe a new microfabrication method based on CO2-laser ablation to generate support membranes with homogeneous apertures ranging from 300 µm down to 84 µm in diameter. They are arranged in arrays with the densest packaging having a perforation level of up to 60%. The apertures are surrounded by a smooth bulge that is formed by melted material ejected from the aperture during laser ablation. Polydimethylsiloxane (PDMS) replicas were used to visualize and analyse these bulges. The overall area covered so far has been 4 cm2 but upscaling to larger footprints, e.g. square metres, is currently being investigated.

  1. Management of trauma to supporting dental structures.

    PubMed

    Elias, Husam; Baur, Dale A

    2009-10-01

    Teeth, periodontium, and supporting alveolar bone are frequently involved in trauma and account for approximately 15% of all emergency room visits. The cause of the dentoalveolar trauma varies in different demographics but generally results from falls, playground accidents, domestic violence, bicycle accidents, motor vehicle accidents, assaults, altercations, and sports injuries. Dentoalveolar injuries should be considered an emergency situation because successful management of the injury requires proper diagnosis and treatment within a limited time to achieve better outcomes. PMID:19958905

  2. ESF GROUND SUPPORT - STRUCTURAL STEEL ANALYSIS

    SciTech Connect

    T. Misiak

    1996-06-26

    The purpose and objective of this analysis are to expand the level of detail and confirm member sizes for steel sets included in the Ground Support Design Analysis, Reference 5.20. This analysis also provides bounding values and details and defines critical design attributes for alternative configurations of the steel set. One possible configuration for the steel set is presented. This analysis covers the steel set design for the Exploratory Studies Facility (ESF) entire Main Loop 25-foot diameter tunnel.

  3. Technologies, Products, and Models Supporting Knowledge Management.

    ERIC Educational Resources Information Center

    Luan, Jing; Serban, Andreea M.

    2002-01-01

    Based on a taxonomy of knowledge management processes, provides a synopsis of technologies and vendors that support knowledge management. Proposes a model for classifying the various types of technologies related to knowledge management that are most often used in institutional research. (EV)

  4. Supporting the Serial in the SERIOL Model

    ERIC Educational Resources Information Center

    Whitney, Carol

    2008-01-01

    It is commonly assumed that orthographical lexical access in visual word recognition takes place in parallel, with all letters activated at the same time. In contrast, in the SERIOL model of letter-position encoding, letters fire sequentially (Whitney, 2001). I present further support for such seriality on several fronts. (1) The reasons that led…

  5. Structural model of channelrhodopsin.

    PubMed

    Watanabe, Hiroshi C; Welke, Kai; Schneider, Franziska; Tsunoda, Satoshi; Zhang, Feng; Deisseroth, Karl; Hegemann, Peter; Elstner, Marcus

    2012-03-01

    Channelrhodopsins (ChRs) are light-gated cation channels that mediate ion transport across membranes in microalgae (vectorial catalysis). ChRs are now widely used for the analysis of neural networks in tissues and living animals with light (optogenetics). For elucidation of functional mechanisms at the atomic level, as well as for further engineering and application, a detailed structure is urgently needed. In the absence of an experimental structure, here we develop a structural ChR model based on several molecular computational approaches, capitalizing on characteristic patterns in amino acid sequences of ChR1, ChR2, Volvox ChRs, Mesostigma ChR, and the recently identified ChR of the halophilic alga Dunaliella salina. In the present model, we identify remarkable structural motifs that may explain fundamental electrophysiological properties of ChR2, ChR1, and their mutants, and in a crucial validation of the model, we successfully reproduce the excitation energy predicted by absorption spectra. PMID:22241469

  6. Design of internal support structures for an inflatable lunar habitat

    NASA Technical Reports Server (NTRS)

    Cameron, Elizabeth A.; Duston, John A.; Lee, David D.

    1990-01-01

    NASA has a long range goal of constructing a fully equipped, manned lunar outpost on the near side of the moon by the year 2015. The proposed outpost includes an inflatable lunar habitat to support crews during missions longer that 12 months. A design for the internal support structures of the inflatable habitat is presented. The design solution includes material selection, substructure design, assembly plan development, and concept scale model construction. Alternate designs and design solutions for each component of the design are discussed. Alternate materials include aluminum, titanium, and reinforced polymers. Vertical support alternates include column systems, truss systems, suspension systems, and lunar lander supports. Horizontal alternates include beams, trusses, floor/truss systems, and expandable trusses. Feasibility studies on each alternate showed that truss systems and expandable trusses were the most feasible candidates for conceptual design. The team based the designs on the properties of 7075 T73 aluminum. The substructure assembly plan, minimizes assembly time and allows crews to construct the habitat without the use of EVA suits. In addition to the design solutions, the report gives conclusions and recommendations for further study of the inflatable habitat design.

  7. Modeling solar magnetic structures

    NASA Technical Reports Server (NTRS)

    Low, B. C.

    1985-01-01

    Some ideas in the theoretical study of force-free magnetic fields and magnetostatic fields, which are relevant to the effort of using magnetograph data as inputs to model the quasi-static, large-scale magnetic structures in the solar atmosphere are discussed. Basic physical principles will be emphasized. An attempt will be made to assess what we may learn, physically, from the models based on these ideas. There is prospect for learning useful physics and this ought to be an incentive for intensifying the efforts to improve vector magnetograph technology and to solve the basic radiative-transfer problems encountered in the interpretation of magnetograph raw data.

  8. A model to support nursing students with dyslexia.

    PubMed

    Salkeld, John

    2016-07-20

    Dyslexia is one of the most commonly declared disabilities in higher educational institutions in the UK. This article explores the effects of specific learning difficulties, in particular dyslexia, on pre-registration nursing students on practice placements in clinical environments. The author proposes use of the OPEL model, which provides a simple, structured framework for supporting nursing students with specific learning difficulties in practice placements. This model could be applied to clinical situations where constructive support is necessary to enable the student to achieve the standards and requirements set by the Nursing and Midwifery Council. PMID:27440364

  9. Clinical ethics support services: an evolving model.

    PubMed

    Schlairet, Maura C; Kiser, Ken; Norris, Stephen

    2012-01-01

    Ethical issues arising in clinical practice are complex and clinicians must be able to manage the needs of ethically vulnerable patients and families. This paper describes a model for providing Clinical Ethics Support Services as a broad spectrum of care for management of conflict and ethically difficult situations in health care and describes how an ethics consultation process was transformed to a Holistic Care Continuum for managing the needs of ethically vulnerable patients. During a 4-year journey at a regional medical center, a Family Support Team played a central role in identification of ethically vulnerable patients/family, interdisciplinary connectivity, and iterative engagement in the clinical milieu. Concepts of professional advocacy and interdisciplinary perspectives resulted in a model for ethically sound patient care promoting communication among patients/family, staff, and professionals; clarification of interdisciplinary roles and responsibilities; establishment of mutually derived goals and shared solutions; and implementation of interventions maximizing institutional resources. PMID:22357314

  10. The Role of Parental Support, Parental Monitoring, and Time Spent with Parents in Adolescent Academic Achievement in Iceland: A Structural Model of Gender Differences

    ERIC Educational Resources Information Center

    Kristjansson, Alfgeir Logi; Sigfusdottir, Inga Dora

    2009-01-01

    This study examines the relationship between parental support, parental monitoring, and time spent with parents and academic achievement among adolescent girls and boys in Iceland, a high-income per-capita Nordic country. The indirect role of school effort is also examined. Data of 7430 9th and 10th graders is analyzed in the study. Structural…

  11. Prioritization of engineering support requests and advanced technology projects using decision support and industrial engineering models

    NASA Technical Reports Server (NTRS)

    Tavana, Madjid

    1995-01-01

    The evaluation and prioritization of Engineering Support Requests (ESR's) is a particularly difficult task at the Kennedy Space Center (KSC) -- Shuttle Project Engineering Office. This difficulty is due to the complexities inherent in the evaluation process and the lack of structured information. The evaluation process must consider a multitude of relevant pieces of information concerning Safety, Supportability, O&M Cost Savings, Process Enhancement, Reliability, and Implementation. Various analytical and normative models developed over the past have helped decision makers at KSC utilize large volumes of information in the evaluation of ESR's. The purpose of this project is to build on the existing methodologies and develop a multiple criteria decision support system that captures the decision maker's beliefs through a series of sequential, rational, and analytical processes. The model utilizes the Analytic Hierarchy Process (AHP), subjective probabilities, the entropy concept, and Maximize Agreement Heuristic (MAH) to enhance the decision maker's intuition in evaluating a set of ESR's.

  12. Support structure for a prestressed cylindrical pressure vessel

    SciTech Connect

    Schoening, J.; Schwiers, H.-G.

    1984-10-02

    A support structure for a nuclear power station having a prestressed cylindrical vessel comprising an annular ring of supports on a support wall and foundation wherein the prestressed cylindrical vessel rests on the ring of supports is disclosed. The supports, through their defined distances from each other, provide a constant cooling flow of the supports and a constant temperature over the entire operating period of the power station. This results in supports that are maintenance-free. The supports are constructed of plastic washers with steel inserts and are of sufficient height such that in the case of earthquakes, maximum vibrations of the reinforced concrete pressure vessel may be absorbed within an accurately set terminal boundary of the annular support wall.

  13. The association between perceived social support and amygdala structure.

    PubMed

    Sato, Wataru; Kochiyama, Takanori; Kubota, Yasutaka; Uono, Shota; Sawada, Reiko; Yoshimura, Sayaka; Toichi, Motomi

    2016-05-01

    The subjective perception of social support plays a crucial role in human well-being. However, its structural neural substrates remain unknown. We hypothesized that the amygdala, specifically its laterobasal and superficial subregions, which have been suggested to serve social functions, could be associated with the level of perceived social support. To test this hypothesis, we assessed perceived social support using the Multidimensional Scale of Perceived Social Support. In addition, we measured the volume and shape of the amygdala using structural magnetic resonance imaging in 49 healthy participants. Global amygdala volume in the left hemisphere was positively associated with the perceived social support score after adjusting for total cerebral volume, sex, age, intelligence, and five-factor personality domains. The local shape of the laterobasal and superficial subregions of the left amygdala showed the same association with perceived social support. These data suggest that the social subregions of the left amygdala are associated with the implementation of perceived social support. PMID:27039164

  14. Model structure identification based on ensemble model evaluation

    NASA Astrophysics Data System (ADS)

    Van Hoey, S.; van der Kwast, J.; Nopens, I.; Seuntjens, P.; Pereira, F.

    2012-04-01

    Identifying the most appropriate hydrological model for a given problem is more than fitting the parameters of a fixed model structure to reproduce the measured hydrograph. Defining the most appropriate model structure is dependent of the modeling objective, the characteristics of the system under investigation and the available data. To be able to adapt to the different conditions and to propose different hypotheses of the underlying system, a flexible model structure is preferred in combination with a rejectionist analysis based on different diagnostics supporting the model objective. By confronting the model structures with the model diagnostics, an identification of the dominant processes is attempted. In the presented work, a set of 24 model structures was constructed, by combining interchangeable components representing different hypotheses of the system under study, the Nete catchment in Belgium. To address the effect of different model diagnostics on the performance of the selected model structures, an optimization of the model structures was performed to identify the parameter sets minimizing specific objective functions, focusing on low or high flow conditions. Furthermore, the different model structures are compared simultaneously within the Generalized Likelihood Uncertainty Estimation (GLUE) approach. The rejection of inadequate model structures by specifying limits of acceptance and weighting of the accepted ones is the basis of the GLUE approach. Multiple measures are combined to give guidance about the suitability of the different structures and information about the identifiability and uncertainty of the parameters is extracted from the ensemble of selected structures. The results of the optimization demonstrate the relationship between the selected objective function and the behaviour of the model structures, but also the compensation for structural differences by different parameter values resulting in similar performance. The optimization gives

  15. APT/LEDA RFQ and support frame structural analysis

    SciTech Connect

    Ellis, S.

    1997-04-01

    This report documents structural analysis of the Accelerator Production of Tritium Low Energy Demonstration Accelerator (APT/LEDA) Radio Frequency Quadrupole (RFQ) accelerator structure and its associated support frame. This work was conducted for the Department of Energy in support of the APT/LEDA. Structural analysis of the RFQ was performed to quantify stress levels and deflections due to both vacuum loading and gravity loading. This analysis also verified the proposed support scheme geometry and quantified interface loads. This analysis also determined the necessary stiffness and strength requirements of the RFQ support frame verifying the conceptual design geometry and allowing specification of individual frame elements. Complete structural analysis of the frame was completed subsequently. This report details structural analysis of the RFQ assembly with regard to gravity and vacuum loads only. Thermally induced stresses from the Radio Frequency (RF) surface resistance heating were not considered.

  16. Combined model for diabetes lifestyle support.

    PubMed

    Gyuk, Peter; Szabo, Istvan; Vassanyi, Istvan; Kosa, Istvan; Kovacs, Levente

    2014-01-01

    Treatment of diabetes mellitus is a public health related problem of modern healthcare. Surveys show that current methods to estimate the required amount of insulin are quite inefficient in practice as they are based on experience. This paper offers a new approach to predict the glucose level of people with diabetes. It combines two efficient models of the literature: one for nutrient absorption and one for glucose control. The combination of them tracks the blood sugar level considering nutrition composition, applied insulin and initial glucose level. Compared to already existing mixed meal models, the current version takes into account a more detailed nutrition composition (protein, lipid, monosaccharide, fiber and starch) supported by our expert dietary systems. Although the model gives satisfactory results even with parameter sets taken from literature, parameter training by genetic algorithms yields a better tracking of the patients. PMID:24743081

  17. Structural system identification: Structural dynamics model validation

    SciTech Connect

    Red-Horse, J.R.

    1997-04-01

    Structural system identification is concerned with the development of systematic procedures and tools for developing predictive analytical models based on a physical structure`s dynamic response characteristics. It is a multidisciplinary process that involves the ability (1) to define high fidelity physics-based analysis models, (2) to acquire accurate test-derived information for physical specimens using diagnostic experiments, (3) to validate the numerical simulation model by reconciling differences that inevitably exist between the analysis model and the experimental data, and (4) to quantify uncertainties in the final system models and subsequent numerical simulations. The goal of this project was to develop structural system identification techniques and software suitable for both research and production applications in code and model validation.

  18. Theory and Modeling in Support of Tether

    NASA Technical Reports Server (NTRS)

    Chang, C. L.; Bergeron, G.; Drobot, A. D.; Papadopoulos, K.; Riyopoulos, S.; Szuszczewicz, E.

    1999-01-01

    This final report summarizes the work performed by SAIC's Applied Physics Operation on the modeling and support of Tethered Satellite System missions (TSS-1 and TSS-1R). The SAIC team, known to be Theory and Modeling in Support of Tether (TMST) investigation, was one of the original twelve teams selected in July, 1985 for the first TSS mission. The accomplishments described in this report cover the period December 19, 1985 to September 31, 1999 and are the result of a continuous effort aimed at supporting the TSS missions in the following major areas. During the contract period, the SAIC's TMST investigation acted to: Participate in the planning and the execution on both of the TSS missions; Provide scientific understanding on the issues involved in the electrodynamic tether system operation prior to the TSS missions; Predict ionospheric conditions encountered during the re-flight mission (TSS-lR) based on realtime global ionosounde data; Perform post mission analyses to enhance our understanding on the TSS results. Specifically, we have 1) constructed and improved current collection models and enhanced our understanding on the current-voltage data; 2) investigated the effects of neutral gas in the current collection processes; 3) conducted laboratory experiments to study the discharge phenomena during and after tether-break; and 4) perform numerical simulations to understand data collected by plasma instruments SPES onboard the TSS satellite; Design and produce multi-media CD that highlights TSS mission achievements and convey the knowledge of the tether technology to the general public. Along with discussions of this work, a list of publications and presentations derived from the TMST investigation spanning the reporting period is compiled.

  19. View of hydrodynamic support cylinders, removed from structure and relocated ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of hydrodynamic support cylinders, removed from structure and relocated for reconditioning to return them to service. - Marshall Space Flight Center, Saturn V Dynamic Test Facility, East Test Area, Huntsville, Madison County, AL

  20. View of possible sluice gate support structure, north center of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of possible sluice gate support structure, north center of the Merry Generator House, looking south - Arthur Holmes Merry Generator House, Signal Lake North of Range Road, Fort Gordon, Richmond County, GA

  1. 109. Detail view of structural frame supporting torch arm; cylindrical ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    109. Detail view of structural frame supporting torch arm; cylindrical object in foreground is part of ventilating system. February 1984. - Statue of Liberty, Liberty Island, Manhattan, New York County, NY

  2. Flood Impact Modelling to support decision making

    NASA Astrophysics Data System (ADS)

    Owen, Gareth; Quinn, Paul; O'Donnell, Greg

    2015-04-01

    Much of what is known about the impacts of landuse change and Natural Flood Management (NFM) is at the local/plot scale. Evidence of the downstream impacts at the larger catchment scale is limited. However, the strategic and financial decisions of land managers, stakeholders and policy makers are made at the larger scale. There are a number of techniques that have the potential to scale local impacts to the catchment scale. This poster will show findings for the 30km2 Leven catchment, North Yorkshire, England. A NFM approach has been adopted by the Environment Agency to reduce flood risk within the catchment. A dense network of stream level gauges were installed in the catchment at the commencement of this project to gain a detailed understanding of the catchment behaviour during storm events. A novel Flood Impact Modelling (FIM) approach has been adopted which uses the network of gauges to disaggregate the outlet hydrograph in terms of source locations. Using a combination of expert opinion and local evidence, the model can be used to assess the impacts of distributed changes in land use management and NFM on flood events. A number of potential future landuse and NFM scenarios have been modelled to investigate their impact on flood peaks. These modelled outcomes are mapped to a simple Decision Support Matrix (DSM). The DSM encourages end users (e.g. land managers and policy makers) to develop an NFM scheme by studying the degree to which local runoff can be attenuated and how that flow will propagate through the network to the point of impact. The DSM relates the impact on flood peaks in terms of alterations to soil management practices and landscape flow connectivity (e.g. soil underdrainage), which can be easily understood by farmers and land managers. The DSM and the FIM together provide a simple to use and transparent modelling tool, making best use of expert knowledge, to support decision making.

  3. Atmospheric analysis modeling in support of Seasat

    NASA Technical Reports Server (NTRS)

    Langland, R. A.; Stephens, P. L.

    1978-01-01

    Atmospheric objective analysis models were developed and tested in preparation for assessing the utility of Seasat data. Of the several discretionary procedures in such computer programs, the effects of three were examined and documented: (1) the effect of varying the weights in the pattern conserving techniques; (2) the effect of varying the data influence region; (3) the effect of including wind information in analysis of mass-structure variables. The problem of inserting bogus reports is also examined.

  4. National Transonic Facility model and model support vibration problems

    NASA Technical Reports Server (NTRS)

    Young, Clarence P., Jr.; Popernack, Thomas G., Jr.; Gloss, Blair B.

    1990-01-01

    Vibrations of models and model support system were encountered during testing in the National Transonic Facility. Model support system yaw plane vibrations have resulted in model strain gage balance design load limits being reached. These high levels of vibrations resulted in limited aerodynamic testing for several wind tunnel models. The yaw vibration problem was the subject of an intensive experimental and analytical investigation which identified the primary source of the yaw excitation and resulted in attenuation of the yaw oscillations to acceptable levels. This paper presents the principal results of analyses and experimental investigation of the yaw plane vibration problems. Also, an overview of plans for development and installation of a permanent model system dynamic and aeroelastic response measurement and monitoring system for the National Transonic Facility is presented.

  5. Teacher Support, School Goal Structures, and Teenage Mothers' School Engagement

    ERIC Educational Resources Information Center

    Kalil, Ariel; Ziol-Guest, Kathleen M.

    2008-01-01

    This study investigates how perceptions of teacher support and achievement goal structures in the school environment correlate with school engagement, and whether depressive symptoms mediate or moderate this association, among 64 low-income teenage mothers. Controlling for prior grades, perceptions of teacher support correlate with higher levels…

  6. Graph based model to support nurses' work.

    PubMed

    Benedik, Peter; Rajkovič, Uroš; Sušteršič, Olga; Prijatelj, Vesna; Rajkovič, Vladislav

    2014-01-01

    Health care is a knowledge-based community that critically depends on knowledge management activities in order to ensure quality. Nurses are primary stakeholders and need to ensure that their information and knowledge needs are being met in such ways that enable them, to improve the quality and efficiency of health care service delivery for all subjects of health care. This paper describes a system to help nurses to create nursing care plan. It supports focusing nurse's attention on those resources/solutions that are likely to be most relevant to their particular situation/problem in nursing domain. System is based on multi-relational property graph representing a flexible modeling construct. Graph allows modeling a nursing domain (ontology) and the indices that partition domain into an efficient, searchable space where the solution to a problem is seen as abstractly defined traversals through its vertices and edges. PMID:24943559

  7. Metallic and Non-Metallic Materials for the Primary Support Structure

    SciTech Connect

    RA Wolf; RP Corson

    2006-02-21

    The primary support structure (PSS) is required for mechanical support of reactor module (RM) components and mounting of the RM to the spacecraft. The PSS would provide support and accept all loads associated with dynamic (e. g., launch and maneuvering) or thermally induced loading. Prior to termination of NRPCT involvement in Project Prometheus, the NRPCT Mechanical Systems team developed preliminary finite element models to gain a basic understanding of the behavior of the structure, but optimization of the models, specification of the final design, and materials selection were not completed. The Space Plant Materials team had evaluated several materials for potential use in the primary support structure, namely titanium alloys, beryllium, aluminum alloys and carbon-carbon composites. The feasibility of application of each material system was compared based on mass, stiffness, thermal expansion, and ease of fabrication. Due to insufficient data on environmental factors, such as temperatures and radiation, and limited modeling support, a final materials selection was not made.

  8. Comparative Protein Structure Modeling Using Modeller

    PubMed Central

    Eswar, Narayanan; Marti-Renom, Marc A.; Madhusudhan, M.S.; Eramian, David; Shen, Min-yi; Pieper, Ursula

    2014-01-01

    Functional characterization of a protein sequence is one of the most frequent problems in biology. This task is usually facilitated by accurate three-dimensional (3-D) structure of the studied protein. In the absence of an experimentally determined structure, comparative or homology modeling can sometimes provide a useful 3-D model for a protein that is related to at least one known protein structure. Comparative modeling predicts the 3-D structure of a given protein sequence (target) based primarily on its alignment to one or more proteins of known structure (templates). The prediction process consists of fold assignment, target-template alignment, model building, and model evaluation. This unit describes how to calculate comparative models using the program MODELLER and discusses all four steps of comparative modeling, frequently observed errors, and some applications. Modeling lactate dehydrogenase from Trichomonas vaginalis (TvLDH) is described as an example. The download and installation of the MODELLER software is also described. PMID:18428767

  9. Design and Analysis of Muon Beam Stop Support Structures

    SciTech Connect

    Okafor, Udenna

    2015-01-01

    The primary objective of this thesis is to design and analyze support structures to be used in the installation, test and final positioning of the MBS throughout the life of the Mu2e experiment. There several requirements for the MBS imposed by both the scope of the experiment and, other components within the DS bore. The functions of the MBS are: 1. To limit the induced rates in the Tracker, the Calorimeter and the Cosmic Ray Veto due to backsplash-and-secondary interactions, and 2. To reduce radiation levels external to the Detector solenoid. The structures used in supporting the MBS will also adhere to requirements imposed by its functions. These requirements are critical to the support structures and affect design decisions. Other requirements critical to the design are imposed by the weight, positional tolerance and assembly procedure of the MBS, and also, the magnetic field and vacuum dose rate of the DS bore. A detailed breakdown of how each requirement affects the structural design can be found in chapter 2. Chapter 3 describes the design of each support structure and its attachment to the MBS while chapter 4 describes the results from structural analysis of the support structures. Chapter 5 describes evaluation for the design through testing and calculations while the conclusion in chapter 6 reports the current status at the time of this thesis submission with a plan for future work to be completed until final design and installation.

  10. Graphite fiber reinforced structure for supporting machine tools

    DOEpatents

    Knight, Jr., Charles E.; Kovach, Louis; Hurst, John S.

    1978-01-01

    Machine tools utilized in precision machine operations require tool support structures which exhibit minimal deflection, thermal expansion and vibration characteristics. The tool support structure of the present invention is a graphite fiber reinforced composite in which layers of the graphite fibers or yarn are disposed in a 0/90.degree. pattern and bonded together with an epoxy resin. The finished composite possesses a low coefficient of thermal expansion and a substantially greater elastic modulus, stiffness-to-weight ratio, and damping factor than a conventional steel tool support utilized in similar machining operations.

  11. Structure for common access and support of fuel cell stacks

    DOEpatents

    Walsh, Michael M.

    2000-01-01

    A structure provides common support and access to multiple fuel cells externally mounted thereto. The structure has openings leading to passages defined therein for providing the access. Various other fuel cell power system components are connected at the openings, such as reactant and coolant sources.

  12. Supported molybdenum carbide catalysts: Structure-function relationships for hydrodenitrogenation

    SciTech Connect

    Dolce, G.M.; Thompson, L.T.

    1997-12-31

    There continues to be a need for new catalysts that can efficiently upgrade petroleum crudes. Heavy oils and coal-derived liquids contain higher levels of nitrogen, sulfur, and oxygen than conventional light crudes, and therefore require more rigorous refining. Currently available commercial catalysts are not as active and efficient at hydrotreating these heavy oils compared to light crudes. Early transition metal carbides and nitrides have been shown to be active for the hydrotreatment of model compounds and petroleum crudes. In this paper the authors describe their investigations of the structural and compositional properties of {gamma}-Al{sub 2}O{sub 3}-supported molybdenum carbides and efforts to correlate these properties with their pyridine and quinoline hydrodenitrogenation (HDN) activities. The HDN activities of the materials scaled linearly with the loading and oxygen chemisorptive uptake. Oxygen chemisorption results also suggested that the molybdenum carbide particles were highly dispersed and perhaps raft-like. Using temperature programmed desorption and infrared spectroscopy of carbon monoxide, they were able to identify two types of sites on the carbides; sites on top of the particle and sites at the perimeter. They have tentatively concluded that the most active sites for HDN were on top of the supported carbide particles.

  13. Development and support structures for high-power solar arrays

    NASA Technical Reports Server (NTRS)

    Knapp, K.

    1984-01-01

    A number of structurally efficient configurations for wing-type solar arrays are developed by a combination of deepening the planform of the blanket and structure and by partitioning the blanket with battens and frequent attachments to the support structure. This technique reduces the tension required to avoid a low natural frequency for the blanket, and the load reduction results in a lighter structure. The use of three different structures are investigated: the Astromast, the Extendible Support Structure (ESS), and a new beam called the STACBEAM (Stacking Triangular Articulated Compact Beam) and their relative performances are compared. The investigation of the STACBEAM is emphasized because its sequential deployment is more reliable for very long systems, and its linear deployment facilitates local attachments to the blanket and the development of a low mass deployer.

  14. Influence of backup bearings and support structure dynamics on the behavior of rotors with active supports

    NASA Technical Reports Server (NTRS)

    Flowers, George T.

    1995-01-01

    Progress made in the current year is listed, and the following papers are included in the appendix: Steady-State Dynamic Behavior of an Auxiliary Bearing Supported Rotor System; Dynamic Behavior of a Magnetic Bearing Supported Jet Engine Rotor with Auxiliary Bearings; Dynamic Modelling and Response Characteristics of a Magnetic Bearing Rotor System with Auxiliary Bearings; and Synchronous Dynamics of a Coupled Shaft/Bearing/Housing System with Auxiliary Support from a Clearance Bearing: Analysis and Experiment.

  15. Control of resonance phenomenon in flexible structures via active support

    NASA Astrophysics Data System (ADS)

    Tavakolpour Saleh, A. R.; Mailah, M.

    2012-07-01

    This paper introduces the concept of active support to cope with the resonance phenomenon in the flexible structures. A valid computational platform for the flexible structure was first presented via a finite difference (FD) approach. Then, the active support mechanism was applied to the simulation algorithm through which the performance of the proposed methodology in suppressing the resonance phenomenon was evaluated. The flexible structure was thus excited with the external disturbance and the system response with and without the effect of the active support was investigated through a simulation study. The simulation outcomes clearly demonstrated effective resonance suppression in the flexible structure. Finally, an experimental rig was developed to investigate the validity of the proposed technique. The experimental results revealed an acceptable agreement with the simulation outcomes through which the validity of the proposed control method was affirmed.

  16. The geometry of the 37-tile microwave antenna support structure

    NASA Technical Reports Server (NTRS)

    Finley, L. A.

    1980-01-01

    The geometry of the support structure for a proposed parabolic shaped microwave antenna is examined. The surface of the antenna is comprised of 37 hexagonal shaped tiles, each connected to a truss module. The units are joined together to form a rigidized, faceted, concave parabolic surface. The geometry specifications are described through an explanation of the structural components which make up the antenna, a description of the coordinate system devised to identify the structure, and a presentation of the nondimensional results.

  17. 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.

  18. Global Urbanization Modeling Supported by Remote Sensing

    NASA Astrophysics Data System (ADS)

    Zhou, Y.; Smith, S.; Zhao, K.; Imhoff, M. L.; Thomson, A. M.; Bond-Lamberty, B. P.; Elvidge, C.

    2014-12-01

    Urbanization, one of the major human induced land cover and land use change, has profound impacts on the Earth system, and plays important roles in a variety of processes such as biodiversity loss, water and carbon cycle, and climate change. Accurate information on urban areas and their spatial distribution at the regional and global scales is important in both scientific and policy-making communities. The Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime stable light data (NTL) provide a potential way to map urban area and its dynamics economically and timely. In this study, we developed a cluster-based method to estimate the optimal thresholds and map urban extents from the DMSP/OLS NTL data. The sensitivity analysis demonstrates the robustness of the derived optimal thresholds and the reliability of the cluster-based method. Compared to existing threshold techniques, our method reduces the over- and under-estimation issue, when mapping urban extent over a large area. Using this cluster-based method, we built new global maps of 1-km urban extent from the NTL data (Figure 1) and evaluated its temporal dynamics from 1992 to 2013. Supported by the derived global urban maps and socio-economic drivers, we developed an integrated modeling framework by integrating a top-down macro-scale statistical model with a bottom-up urban growth model and projected future urban expansion.

  19. Depth Structure from Asymmetric Shading Supports Face Discrimination

    PubMed Central

    Chen, Chien-Chung; Chen, Chin-Mei; Tyler, Christopher W.

    2013-01-01

    To examine the effect of illumination direction on the ability of observers to discriminate between faces, we manipulated the direction of illumination on scanned 3D face models. In order to dissociate the surface reflectance and illumination components of front-view face images, we introduce a symmetry algorithm that can separate the symmetric and asymmetric components of the face in both low and high spatial frequency bands. Based on this approach, hybrid faces stimuli were constructed with different combinations of symmetric and asymmetric spatial content. Discrimination results with these images showed that asymmetric illumination information biased face perception toward the structure of the shading component, while the symmetric illumination information had little, if any, effect. Measures of perceived depth showed that this property increased systematically with the asymmetric but not the symmetric low spatial frequency component. Together, these results suggest that (1) the asymmetric 3D shading information dramatically affects both the perceived facial information and the perceived depth of the facial structure; and (2) these effects both increase as the illumination direction is shifted to the side. Thus, our results support the hypothesis that face processing has a strong 3D component. PMID:23457484

  20. Structural model of uramarsite

    SciTech Connect

    Rastsvetaeva, R. K.; Sidorenko, G. A.; Ivanova, A. G.; Chukanov, N. V.

    2008-09-15

    The structural model of uramarsite, a new mineral of the uran-mica family from the Bota-Burum deposit (South Kazakhstan), is determined using a single-crystal X-ray diffraction analysis. The parameters of the triclinic unit cell are as follows: a = 7.173(2) A, b = 7.167(5) A, c = 9.30(1) A, {alpha} = 90.13(7){sup o}, {beta} = 90.09(4){sup o}, {gamma} = 89.96(4){sup o}, and space group P1. The crystal chemical formula of uramarsite is: (UO{sub 2}){sub 2}[AsO{sub 4}][PO{sub 4},AsO{sub 4}][NH{sub 4}][H{sub 3}O] . 6H{sub 2}O (Z = 1). Uramarsite is the second ammonium-containing mineral of uranium and an arsenate analogue of uramphite. In the case of uramarsite, the lowering of the symmetry from tetragonal to triclinic, which is accompanied by a triclinic distortion of the tetragonal unit cell, is apparently caused by the ordering of the As and P atoms and the NH{sub 4}, H{sub 3}O, and H{sub 2}O groups.

  1. Support for an expanded tripartite influence model with gay men.

    PubMed

    Tylka, Tracy L; Andorka, Michael J

    2012-01-01

    This study investigated whether an expanded tripartite influence model would represent gay men's experiences. This model was extended by adding partners and gay community involvement as sources of social influence and considering dual body image pathways (muscularity and body fat dissatisfaction) to muscularity enhancement and disordered eating behaviors. Latent variable structural equation modeling analyses upheld this model for 346 gay men. Dual body image pathways to body change behaviors were supported, although three unanticipated interrelationships emerged, suggesting that muscularity and body fat concerns and behaviors may be more integrated for gay men. Internalization of the mesomorphic ideal, appearance comparison, muscularity dissatisfaction, and body fat dissatisfaction were key mediators in the model. Of the sources of social influence, friend and media pressure to be lean, gay community involvement, and partner, friend, media, and family pressures to be muscular made incremental contributions. Unexpectedly, certain sources were directly connected to body change behaviors. PMID:22036192

  2. Wavelet modelling in support of IRI

    NASA Astrophysics Data System (ADS)

    Schmidt, Michael

    The slant total electron content (STEC) of the ionosphere is defined as the integral of the electron density along the ray-path of the signal between the transmitter and the receiver. So-called geometry free GPS measurements provide information on the electron density, which is basically a four-dimensional function depending on spatial position and time. Since ground-based measurements are not very sensitive to the vertical structure within the atmosphere, the ionosphere is often represented by a spherical layer, where all electrons are concentrated. Then the STEC is transformed into the vertical total electron content (VTEC), which is a three-dimensional function depending on longitude, latitude and time. In our approach, we decompose an ionospheric function, i.e. the electron density or the VTEC, into a reference part computed from a given model like the International Reference Ionosphere (IRI) and an unknown correction term expanded in a multi-dimensional series in terms of localizing base functions. The corresponding series coefficients are calculable from GPS measurements applying parameter estimation procedures. Since the GPS receivers are located rather unbalanced, finer structures are modelable just in regions with a sufficient number of observation sites. Due to the localizing feature of B-spline functions we apply a tensor product spline expansion to model the correction term regionally. Furthermore, the multi-resolution representation derived from wavelet analysis allows monitoring the ionosphere at different resolutions levels. We demonstrate the advantages of this procedure by representing a simulated VTEC data set over South America.

  3. Pore structure characterization of catalyst supports via low field NMR

    SciTech Connect

    Smith, D.M.; Glaves, C.L.; Gallegos, D.P.; Brinker, C.J.

    1988-01-01

    In this paper, the application of low-field NMR to both surface area and pore structure analysis of catalyst supports will be presented. Low-field (20 MHz) spin-lattice relaxation (T/sub 1/) experiments are performed on fluids contained in alumina and silica catalyst supports. Pore size distributions (PSD) calculated from these NMR experiments are compared to those obtained from mercury porosimetry and nitrogen condensation. 18 refs., 4 figs., 2 tabs.

  4. IHY Modeling Support at the Community Coordinated Modeling Center

    NASA Technical Reports Server (NTRS)

    Chulaki, A.; Hesse, Michael; Kuznetsova, Masha; MacNeice, P.; Rastaetter, L.

    2005-01-01

    The Community Coordinated Modeling Center (CCMC) is a US inter-agency activity aiming at research in support of the generation of advanced space weather models. As one of its main functions, the CCMC provides to researchers the use of space science models, even if they are not model owners themselves. In particular, the CCMC provides to the research community the execution of "runs-onrequest" for specific events of interest to space science researchers. Through this activity and the concurrent development of advanced visualization tools, CCMC provides, to the general science community, unprecedented access to a large number of state-of-the-art research models. CCMC houses models that cover the entire domain from the Sun to the Earth. In this presentation, we will provide an overview of CCMC modeling services that are available to support activities during the International Heliospheric Year. In order to tailor CCMC activities to IHY needs, we will also invite community input into our IHY planning activities.

  5. Spatial Cognition Support for Exploring the Design Mechanics of Building Structures

    ERIC Educational Resources Information Center

    Rudy, Margit; Hauck, Richard

    2008-01-01

    A web-based tool for visualizing the simulated structural behavior of building models was developed to support the teaching of structural design to architecture and engineering students by activating their spatial cognition capabilities. The main didactic issues involved establishing a consistent and complete three-dimensional vocabulary (3D)…

  6. Superconducting magnetic energy storage apparatus structural support system

    DOEpatents

    Withers, Gregory J.; Meier, Stephen W.; Walter, Robert J.; Child, Michael D.; DeGraaf, Douglas W.

    1992-01-01

    A superconducting magnetic energy storage apparatus comprising a cylindrical superconducting coil; a cylindrical coil containment vessel enclosing the coil and adapted to hold a liquid, such as liquefied helium; and a cylindrical vacuum vessel enclosing the coil containment vessel and located in a restraining structure having inner and outer circumferential walls and a floor; the apparatus being provided with horizontal compression members between (1) the coil and the coil containment vessel and (2) between the coil containment vessel and the vacuum vessel, compression bearing members between the vacuum vessel and the restraining structure inner and outer walls, vertical support members (1) between the coil bottom and the coil containment vessel bottom and (2) between the coil containment vessel bottom and the vacuum vessel bottom, and external supports between the vacuum vessel bottom and the restraining structure floor, whereby the loads developed by thermal and magnetic energy changes in the apparatus can be accommodated and the structural integrity of the apparatus be maintained.

  7. PORFLOW Modeling Supporting The H-Tank Farm Performance Assessment

    SciTech Connect

    Jordan, J. M.; Flach, G. P.; Westbrook, M. L.

    2012-08-31

    Numerical simulations of groundwater flow and contaminant transport in the vadose and saturated zones have been conducted using the PORFLOW code in support of an overall Performance Assessment (PA) of the H-Tank Farm. This report provides technical detail on selected aspects of PORFLOW model development and describes the structure of the associated electronic files. The PORFLOW models for the H-Tank Farm PA, Rev. 1 were updated with grout, solubility, and inventory changes. The aquifer model was refined. In addition, a set of flow sensitivity runs were performed to allow flow to be varied in the related probabilistic GoldSim models. The final PORFLOW concentration values are used as input into a GoldSim dose calculator.

  8. Mutual Support: A Model of Participatory Support by and for People with Learning Difficulties

    ERIC Educational Resources Information Center

    Keyes, Sarah E.; Brandon, Toby

    2012-01-01

    Mutual Support, a model of peer support by and for people with learning difficulties, was constructed through a participatory research process. The research focussed on individual narratives from people with learning difficulties. These narratives were then brought together to form a collective model of support. This paper outlines the detailed…

  9. Structural Support of High-Performance Athletes' Education: Supporting Dual Careers in Greece

    ERIC Educational Resources Information Center

    Pavlidis, George; Gargalianos, Dimitris

    2014-01-01

    This article describes how the current Greek sport-education context seems to offer relatively poor dual-career support in comparison to other available structures in the world. This results in additional obstacles for Greek athletes who wish to educate themselves and an ambiguous prospect for their future. Consequently, the Greek…

  10. Supporting Teachers' Reflection and Learning through Structured Digital Teaching Portfolios

    ERIC Educational Resources Information Center

    Sung, Y. -T.; Chang, K. -E.; Yu, W. -C.; Chang, T. -H.

    2009-01-01

    Digital teaching portfolios have been proposed as an effective tool for teacher learning and professional development, but there is a lack of empirical evidence supporting their effectiveness. This study proposed the design of a structured digital portfolio equipped with multiple aids (e.g. self-assessment, peer assessment, discussion and journal…

  11. Review and new thinking on LAMOST focal plate support structure

    NASA Astrophysics Data System (ADS)

    Wang, Guomin; Zhang, Kun

    2010-07-01

    LAMOST is a kind of special reflecting Schmidt telescope which solved the problem to achieve both wide FOV and large aperture on one telescope. This feature makes it competitive to do the large sky area survey work. According to the configuration, the focal plate of this kind of telescope will perform three main motions: derotation, tilt and focusing. Normally the focal plate will be supported at a certain height above ground. China has launched the astronomy research at Antarctic Dome A and planned to set up a LAMOST-style telescope there. Considering the harsh environment and terrible remote transportation, a kind of simple and compact support structure of focal plate is proposed in this paper aiming at light weight, easy installation and easy adjustment, based on the review of LAMOST experiments. The calculation and simulation results show that the compact support structure can meet the system requirements.

  12. Control and modeling of a CELSS (Controlled Ecological Life Support System)

    NASA Technical Reports Server (NTRS)

    Auslander, D. M.; Spear, R. C.; Babcock, P. S.; Nadel, M.

    1983-01-01

    Research topics that arise from the conceptualization of control for closed life support systems which are life support systems in which all or most of the mass is recycled are discussed. Modeling and control of uncertain and poorly defined systems, resource allocation in closed life support systems, and control structures or systems with delay and closure are emphasized.

  13. Engaging Students in Learning Activities: It Is Not Autonomy Support or Structure but Autonomy Support and Structure

    ERIC Educational Resources Information Center

    Jang, Hyungshim; Reeve, Johnmarshall; Deci, Edward L.

    2010-01-01

    We investigated 2 engagement-fostering aspects of teachers' instructional styles--autonomy support and structure--and hypothesized that students' engagement would be highest when teachers provided high levels of both. Trained observers rated teachers' instructional styles and students' behavioral engagement in 133 public high school classrooms in…

  14. Structural Modeling Using "Scanning and Mapping" Technique

    NASA Technical Reports Server (NTRS)

    Amos, Courtney L.; Dash, Gerald S.; Shen, J. Y.; Ferguson, Frederick; Noga, Donald F. (Technical Monitor)

    2000-01-01

    Supported by NASA Glenn Center, we are in the process developing a structural damage diagnostic and monitoring system for rocket engines, which consists of five modules: Structural Modeling, Measurement Data Pre-Processor, Structural System Identification, Damage Detection Criterion, and Computer Visualization. The function of the system is to detect damage as it is incurred by the engine structures. The scientific principle to identify damage is to utilize the changes in the vibrational properties between the pre-damaged and post-damaged structures. The vibrational properties of the pre-damaged structure can be obtained based on an analytic computer model of the structure. Thus, as the first stage of the whole research plan, we currently focus on the first module - Structural Modeling. Three computer software packages are selected, and will be integrated for this purpose. They are PhotoModeler-Pro, AutoCAD-R14, and MSC/NASTRAN. AutoCAD is the most popular PC-CAD system currently available in the market. For our purpose, it plays like an interface to generate structural models of any particular engine parts or assembly, which is then passed to MSC/NASTRAN for extracting structural dynamic properties. Although AutoCAD is a powerful structural modeling tool, the complexity of engine components requires a further improvement in structural modeling techniques. We are working on a so-called "scanning and mapping" technique, which is a relatively new technique. The basic idea is to producing a full and accurate 3D structural model by tracing on multiple overlapping photographs taken from different angles. There is no need to input point positions, angles, distances or axes. Photographs can be taken by any types of cameras with different lenses. With the integration of such a modeling technique, the capability of structural modeling will be enhanced. The prototypes of any complex structural components will be produced by PhotoModeler first based on existing similar

  15. An Application of the Social Support Deterioration Deterrence Model to Rescue Workers

    ERIC Educational Resources Information Center

    Prati, Gabriele; Pietrantoni, Luca

    2010-01-01

    This study examined the role of social support in promoting quality of life in the aftermath of critical incidents involvement. Participants were a sample of 586 Italian rescue workers. Structural equation modelling was used to test the social support deterioration deterrence model. Results showed that the impact of critical incident involvement…

  16. Design integration of favorable geometry, structural support and containment

    SciTech Connect

    Purcell, J.A.; McGehee, G.A.

    1991-07-01

    In designs for fissile processes at Savannah River site, different approaches have been used to provide engineered margins of safety for criticality with containment and seismic resistance as additional requirements. These requirements are frequently at odds in engineered systems. This paper proposes a plan to take advantage of vessels with favorable geometry to provide seismic resistance and to support a glovebox for containment. Thin slab tanks, small diameter pencil tanks, annular tanks, and other novel designs have been used for criticality safety. The requirement for DBE seismic resistance and rigid control of dimensions leads the designer to consider annular tanks for meeting these requirements. The high strength of annular tanks may logically be used to support secondary containment. Hands-on access to all instruments, piping etc. within containment can be provided through gloveports, thus a specialized glovebox. This paper examines the advantages of using an annular tank design to provide favorable geometry, structural support and containment.

  17. Job Demands-Control-Support model and employee safety performance.

    PubMed

    Turner, Nick; Stride, Chris B; Carter, Angela J; McCaughey, Deirdre; Carroll, Anthony E

    2012-03-01

    The aim of this study was to explore whether work characteristics (job demands, job control, social support) comprising Karasek and Theorell's (1990) Job Demands-Control-Support framework predict employee safety performance (safety compliance and safety participation; Neal and Griffin, 2006). We used cross-sectional data of self-reported work characteristics and employee safety performance from 280 healthcare staff (doctors, nurses, and administrative staff) from Emergency Departments of seven hospitals in the United Kingdom. We analyzed these data using a structural equation model that simultaneously regressed safety compliance and safety participation on the main effects of each of the aforementioned work characteristics, their two-way interactions, and the three-way interaction among them, while controlling for demographic, occupational, and organizational characteristics. Social support was positively related to safety compliance, and both job control and the two-way interaction between job control and social support were positively related to safety participation. How work design is related to employee safety performance remains an important area for research and provides insight into how organizations can improve workplace safety. The current findings emphasize the importance of the co-worker in promoting both safety compliance and safety participation. PMID:22269573

  18. Supporting Students' Knowledge Transfer in Modeling Activities

    ERIC Educational Resources Information Center

    Piksööt, Jaanika; Sarapuu, Tago

    2014-01-01

    This study investigates ways to enhance secondary school students' knowledge transfer in complex science domains by implementing question prompts. Two samples of students applied two web-based models to study molecular genetics--the model of genetic code (n = 258) and translation (n = 245). For each model, the samples were randomly divided into…

  19. Modeling uncertainty in requirements engineering decision support

    NASA Technical Reports Server (NTRS)

    Feather, Martin S.; Maynard-Zhang, Pedrito; Kiper, James D.

    2005-01-01

    One inherent characteristic of requrements engineering is a lack of certainty during this early phase of a project. Nevertheless, decisions about requirements must be made in spite of this uncertainty. Here we describe the context in which we are exploring this, and some initial work to support elicitation of uncertain requirements, and to deal with the combination of such information from multiple stakeholders.

  20. Evidence for Supporting the Black Hole Universe Model

    NASA Astrophysics Data System (ADS)

    Zhang, Tianxi

    2013-06-01

    According to Zhang’s recently proposed black hole universe model, the universe originated from a hot star-like black hole and grew up from a supermassive black hole to the present state by accreting ambient matter including radiation and merging with other black holes. With a single hypothesis that a black hole constructs its own spacetime or a spacetime encloses a black hole, this new cosmological model can explain all our observations of the universe to date with the well-developed physics. The observable and non-observable spaces of the universe are hierarchically layered instead of isotropically uniform. His previous work has explained various aspects of the black hole universe such as the origin, structure, evolution, expansion, and acceleration of the black hole universe; the cosmic microwave background radiation; the energy emission of quasars; and the black hole nucleosynthesis. This study explores more evidence for supporting the black hole universe model. We will investigate: (i) the emission of dynamic black holes to explain gamma ray bursts and X-ray flares of the massive black hole at the center of Milky Way, (ii) the structure of the black hole universe to explain the greater attractors and dark flows, and (iii) the evolution of the black hole universe to explain the discovery of old galactic clusters in the young universe and the enrichment of heavy elements around the distant quasars. We will also address other properties of the black hole universe and compare this new cosmological model with the big bang theory.

  1. EPA-SUPPORTED (ENVIRONMENTAL PROTECTION AGENCY-SUPPORTED) WASTELOAD ALLOCATION MODELS

    EPA Science Inventory

    Modeling is increasingly becoming part of the Wasteload Allocation Process. The U.S. EPA provides guidance, technical training and computer software in support of this program. This paper reviews the support available to modelers through the Wasteload Allocation Section of EPA's ...

  2. Rhode Island Model Evaluation & Support System: Teacher. Edition III

    ERIC Educational Resources Information Center

    Rhode Island Department of Education, 2015

    2015-01-01

    Rhode Island educators believe that implementing a fair, accurate, and meaningful educator evaluation and support system will help improve teaching and learning. The primary purpose of the Rhode Island Model Teacher Evaluation and Support System (Rhode Island Model) is to help all teachers improve. Through the Model, the goal is to help create a…

  3. Structure function analysis of mirror fabrication and support errors

    NASA Astrophysics Data System (ADS)

    Hvisc, Anastacia M.; Burge, James H.

    2007-09-01

    Telescopes are ultimately limited by atmospheric turbulence, which is commonly characterized by a structure function. The telescope optics will not further degrade the performance if their errors are small compared to the atmospheric effects. Any further improvement to the mirrors is not economical since there is no increased benefit to performance. Typically the telescope specification is written in terms of an image size or encircled energy and is derived from the best seeing that is expected at the site. Ideally, the fabrication and support errors should never exceed atmospheric turbulence at any spatial scale, so it is instructive to look at how these errors affect the structure function of the telescope. The fabrication and support errors are most naturally described by Zernike polynomials or by bending modes for the active mirrors. This paper illustrates an efficient technique for relating this modal analysis to wavefront structure functions. Data is provided for efficient calculation of structure function given coefficients for Zernike annular polynomials. An example of this procedure for the Giant Magellan Telescope primary mirror is described.

  4. Structural Benchmark Tests of Composite Combustion Chamber Support Completed

    NASA Technical Reports Server (NTRS)

    Krause, David L.; Thesken, John C.; Shin, E. Eugene; Sutter, James K.

    2005-01-01

    A series of mechanical load tests was completed on several novel design concepts for extremely lightweight combustion chamber support structures at the NASA Glenn Research Center (http://www.nasa.gov/glenn/). The tests included compliance evaluation, preliminary proof loadings, high-strain cyclic testing, and finally residual strength testing of each design (see the photograph on the left). Loads were applied with single rollers (see the photograph on the right) or pressure plates (not shown) located midspan on each side to minimize the influence of contact stresses on corner deformation measurements. Where rollers alone were used, a more severe structural loading was produced than the corresponding equal-force pressure loading: the maximum transverse shear force existed over the entire length of each side, and the corner bending moments were greater than for a distributed (pressure) loading. Failure modes initiating at the corner only provided a qualitative indication of the performance limitations since the stress state was not identical to internal pressure. Configurations were tested at both room and elevated temperatures. Experimental results were used to evaluate analytical prediction tools and finite-element methodologies for future work, and they were essential to provide insight into the deformation at the corners. The tests also were used to assess fabrication and bonding details for the complicated structures. They will be used to further optimize the design of the support structures for weight performance and the efficacy of corner reinforcement.

  5. Concepts to Support HRP Integration Using Publications and Modeling

    NASA Technical Reports Server (NTRS)

    Mindock, J.; Lumpkins, S.; Shelhamer, M.

    2014-01-01

    Initial efforts are underway to enhance the Human Research Program (HRP)'s identification and support of potential cross-disciplinary scientific collaborations. To increase the emphasis on integration in HRP's science portfolio management, concepts are being explored through the development of a set of tools. These tools are intended to enable modeling, analysis, and visualization of the state of the human system in the spaceflight environment; HRP's current understanding of that state with an indication of uncertainties; and how that state changes due to HRP programmatic progress and design reference mission definitions. In this talk, we will discuss proof-of-concept work performed using a subset of publications captured in the HRP publications database. The publications were tagged in the database with words representing factors influencing health and performance in spaceflight, as well as with words representing the risks HRP research is reducing. Analysis was performed on the publication tag data to identify relationships between factors and between risks. Network representations were then created as one type of visualization of these relationships. This enables future analyses of the structure of the networks based on results from network theory. Such analyses can provide insights into HRP's current human system knowledge state as informed by the publication data. The network structure analyses can also elucidate potential improvements by identifying network connections to establish or strengthen for maximized information flow. The relationships identified in the publication data were subsequently used as inputs to a model captured in the Systems Modeling Language (SysML), which functions as a repository for relationship information to be gleaned from multiple sources. Example network visualization outputs from a simple SysML model were then also created to compare to the visualizations based on the publication data only. We will also discuss ideas for

  6. Enhancing reuse of structured eligibility criteria and supporting their relaxation.

    PubMed

    Milian, Krystyna; Hoekstra, Rinke; Bucur, Anca; Ten Teije, Annette; van Harmelen, Frank; Paulissen, John

    2015-08-01

    Patient recruitment is one of the most important barriers to successful completion of clinical trials and thus to obtaining evidence about new methods for prevention, diagnostics and treatment. The reason is that recruitment is effort consuming. It requires the identification of candidate patients for the trial (the population under study), and verifying for each patient whether the eligibility criteria are met. The work we describe in this paper aims to support the comparison of population under study in different trials, and the design of eligibility criteria for new trials. We do this by introducing structured eligibility criteria, that enhance reuse of criteria across trials. We developed a method that allows for automated structuring of criteria from text. Additionally, structured eligibility criteria allow us to propose suggestions for relaxation of criteria to remove potentially unnecessarily restrictive conditions. We thereby increase the recruitment potential and generalizability of a trial. Our method for automated structuring of criteria enables us to identify related conditions and to compare their restrictiveness. The comparison is based on the general meaning of criteria, comprised of commonly occurring contextual patterns, medical concepts and constraining values. These are automatically identified using our pattern detection algorithm, state of the art ontology annotators and semantic taggers. The comparison uses predefined relations between the patterns, concept equivalences defined in medical ontologies, and threshold values. The result is a library of structured eligibility criteria which can be browsed using fine grained queries. Furthermore, we developed visualizations for the library that enable intuitive navigation of relations between trials, criteria and concepts. These visualizations expose interesting co-occurrences and correlations, potentially enhancing meta-research. The method for criteria structuring processes only certain types of

  7. Making Plant-Support Structures From Waste Plant Fiber

    NASA Technical Reports Server (NTRS)

    Morrow, Robert C.; < oscjmocl. < attjew K/; {ertzbprm. A,amda; Ej (e. Cjad); Hunt, John

    2006-01-01

    Environmentally benign, biodegradable structures for supporting growing plants can be made in a process based on recycling of such waste plant fiber materials as wheat straw or of such derivative materials as paper and cardboard. Examples of structures that can be made in this way include plant plugs, pots, planter-lining mats, plant fences, and root and shoot barriers. No chemical binders are used in the process. First, the plant material is chopped into smaller particles. The particles are leached with water or steam to remove material that can inhibit plant growth, yielding a fibrous slurry. If the desired structures are plugs or sheets, then the slurry is formed into the desired shapes in a pulp molding subprocess. If the desired structures are root and shoot barriers, pots, or fences, then the slurry is compression-molded to the desired shapes in a heated press. The processed materials in these structures have properties similar to those of commercial pressboard, but unlike pressboard, these materials contain no additives. These structures have been found to withstand one growth cycle, even when wet

  8. Operational support for a range-dependent radio propagation model

    NASA Astrophysics Data System (ADS)

    Cook, John; Vogel, Gerard; Love, Gary

    1995-02-01

    The emerging new standard in the U.S. Navy for range-dependent radio propagation assessment is the Radio Physical Optics (RPO) model developed at the Naval Command, Control and Ocean Surveillance Center, RDT&E Division (NRaD). RPO allows one to compare the expected radio propagation loss field as a function of height along a desired bearing, provided the atmospheric propagation conditions are specified along the path. This paper describes an architecture being developed to operationally support RPO. In developing this architecture, a number of unique constraints and considerations have been dealt with to provide RPO with cross-sections of atmospheric propagation conditions. First, forecast grids from a mesoscale weather data assimilation/prediction model are accessed to provide the best estimate of the current and future refractive and meteorological conditions over the area of interest. Based on conditions near the surface, high-resolution profiles of refractivity in the evaporation duct are calculated and appended onto the bottom of the model forecast profiles. This completes the specification of refractivity down to the sea surface. These refractivity profiles are then processed by a unique algorithm that matches similar refractivity structures from profile-to-profile and reformats the data to support the indexing scheme required by RPO. After RPO has been run, the propagation loss results can be displayed and thresholded to provide expected coverage against specific targets. An example will be shown where multiple RPO runs are used to suggest positioning of available assets to maximize coverage.

  9. Crop Simulation Models and Decision Support Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The first computer simulation models for agricultural systems were developed in the 1970s. These early models simulated potential production for major crops as a function of weather conditions, especially temperature and solar radiation. At a later stage, the water component was added to be able to ...

  10. Structural cost optimization of photovoltaic central power station modules and support structure

    NASA Technical Reports Server (NTRS)

    Sutton, P. D.; Stolte, W. J.; Marsh, R. O.

    1979-01-01

    The results of a comprehensive study of photovoltaic module structural support concepts for photovoltaic central power stations and their associated costs are presented. The objective of the study has been the identification of structural cost drivers. Parametric structural design and cost analyses of complete array systems consisting of modules, primary support structures, and foundations were performed. Area related module cost was found to be constant with design, size, and loading. A curved glass module concept was evaluated and found to have the potential to significantly reduce panel structural costs. Conclusions of the study are: array costs do not vary greatly among the designs evaluated; panel and array costs are strongly dependent on design loading; and the best support configuration is load dependent

  11. Summer Support of the Advanced Structures and Measurements Group

    NASA Technical Reports Server (NTRS)

    Stuber, Alexander Lee

    2010-01-01

    This presentation is my exit presentation summarizing the work that I did this summer during my 10 week summer internship. It is primarily focused on tensile testing of composite coupons including the use of the ARAMIS optical strain measurement system, but it also includes some discussion of other support that I provided for the Dryden composites working group effort. My main efforts in that area were focused on T-joint design for an upcoming hands-on-workshop as well as design of a fixture to test joint coupons. Finally, there is a brief discussion of the other small projects that I worked on, including support of structurally integrated thermal protection system (STIPS) research and the Global Observer wing loads test.

  12. STS-49 Astronaut By Mission Peculiar Equipment Support Structure (MPESS)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-49, the first flight of the Space Shuttle Orbiter Endeavour, lifted off from launch pad 39B on May 7, 1992 at 6:40 pm CDT. The STS-49 mission was the first U.S. orbital flight to feature 4 extravehicular activities (EVAs), and the first flight to involve 3 crew members working simultaneously outside of the spacecraft. The primary objective was the capture and redeployment of the INTELSAT VI (F-3), a communication satellite for the International Telecommunication Satellite organization, which was stranded in an unusable orbit since its launch aboard the Titan rocket in March 1990. In this onboard photo, astronaut Thomas Akers is positioned near the Mission Peculiar Equipment Support Structure (MPESS) in the cargo bay. The MPESS, developed by Marshall Space Flight Center, was used to support experiments.

  13. Crankshaft supporting structure for multicylinder internal combustion engines

    SciTech Connect

    Fukuo, K.; Ito, T.; Ichida, K.

    1988-03-08

    A crankshaft supporting structure in a multicylinder internal combustion engine is described including a bearing caps secured respectively to journal walls integral with a crankcase of a cylinder block, a crankshaft rotatably supported between the journal walls and the bearing caps, at least one counterweight on the crankshaft, and a bridge interconnecting the bearing caps. The bridge includes integral baffle plates extending between locations of the bearing caps and curved along a path of outer peripheral surfaces of each counterweight on the crankshaft. The bridge includes an oil supply gallery which extends substantially along a length of the bridge and generally parallel to the crankshaft and branch passages are provided in the bridge and the bearing caps extending from the gallery to a bearing hole defined by each journal wall and bearing cap.

  14. Crankshaft supporting structure for multicylinder internal combustion combustion engines

    SciTech Connect

    Fukuo, K.; Chosa, M.; Kazama, A.; Anno, N.; Kusakabe, Y.

    1988-06-28

    A crankshaft support structure is described for a multicylinder engine, comprising, a cylinder block of a lightweight material having a first coefficient of thermal expansion, the cylinder block extending longitudinally along the crankshaft and having a plurality of lateral extending and longitudinally spaced journal walls. Bearing caps of heavyweight material have a second coefficient of thermal expansion different from the first coefficient, a bearing cap mounted on each journal wall, the bearing caps and journal walls define bearing holes therebetween for supporting the crankshaft, a bridge of a lightweight material having a coefficient of thermal expansion which is substantially equal to the first coefficient, the bridge extending longitudinally over the bearing caps, and means mounting the bridge and bearing caps of the journal walls whereby the cylinder block and bridge undergo a substantially equal amount of thermal expansion and the bearing caps undergo a different amount of thermal expansion which is accommodated by the cylinder block and bridge.

  15. Organizational Structures and Processes to Support and Sustain Effective Technical Assistance in a State-Wide Multi-Tiered System of Support Initiative

    ERIC Educational Resources Information Center

    Morrison, Julie Q.; Russell, Christine; Dyer, Stephanie; Metcalf, Terri; Rahschulte, Rebecca L.

    2014-01-01

    Despite the national proliferation of technical assistance as a driver for school reform and as a model for embedded and sustained professional development, very little is known about the organizational structures and processes needed to support technical assistance. The purpose of this paper is to describe a structured needs assessment process…

  16. Controlled Ecological Life Support System (CELSS) modeling

    NASA Technical Reports Server (NTRS)

    Drysdale, Alan; Thomas, Mark; Fresa, Mark; Wheeler, Ray

    1992-01-01

    Attention is given to CELSS, a critical technology for the Space Exploration Initiative. OCAM (object-oriented CELSS analysis and modeling) models carbon, hydrogen, and oxygen recycling. Multiple crops and plant types can be simulated. Resource recovery options from inedible biomass include leaching, enzyme treatment, aerobic digestion, and mushroom and fish growth. The benefit of using many small crops overlapping in time, instead of a single large crop, is demonstrated. Unanticipated results include startup transients which reduce the benefit of multiple small crops. The relative contributions of mass, energy, and manpower to system cost are analyzed in order to determine appropriate research directions.

  17. Supporting shared data structures on distributed memory architectures

    NASA Technical Reports Server (NTRS)

    Koelbel, Charles; Mehrotra, Piyush; Vanrosendale, John

    1990-01-01

    Programming nonshared memory systems is more difficult than programming shared memory systems, since there is no support for shared data structures. Current programming languages for distributed memory architectures force the user to decompose all data structures into separate pieces, with each piece owned by one of the processors in the machine, and with all communication explicitly specified by low-level message-passing primitives. A new programming environment is presented for distributed memory architectures, providing a global name space and allowing direct access to remote parts of data values. The analysis and program transformations required to implement this environment are described, and the efficiency of the resulting code on the NCUBE/7 and IPSC/2 hypercubes are described.

  18. Static analysis of cable networks and their supporting structures

    SciTech Connect

    Mitsugi, J.

    1994-04-01

    A nonlinear static analysis method for cable structures, particularly emphasizing cable networks, is presented. Cable strains are measured from the current geometry and compressed cables are analytically disassembled with the construction of the equilibrium equation and the stiffness matrix. Finite rotations of cable intersections, referred to as nodes, and cable elements passing through more than two nodes are included in the formulation. An integrated analysis with a linear finite element method is also presented to account for the elastic deformations of supporting structures for the cable networks. The formulation is programmed for a CRAY2 supercomputer using parallel processing to solve the linear equations. Applications of the method used for mesh antenna development are also presented. 13 refs.

  19. Using Covariation Reasoning to Support Mathematical Modeling

    ERIC Educational Resources Information Center

    Jacobson, Erik

    2014-01-01

    For many students, making connections between mathematical ideas and the real world is one of the most intriguing and rewarding aspects of the study of mathematics. In the Common Core State Standards for Mathematics (CCSSI 2010), mathematical modeling is highlighted as a mathematical practice standard for all grades. To engage in mathematical…

  20. Strategies to Support Students' Mathematical Modeling

    ERIC Educational Resources Information Center

    Jung, Hyunyi

    2015-01-01

    An important question for mathematics teachers is this: "How can we help students learn mathematics to solve everyday problems, rather than teaching them only to memorize rules and practice mathematical procedures?" Teaching students using modeling activities can help them learn mathematics in real-world problem-solving situations that…

  1. Rhode Island Model Evaluation & Support System: Building Administrator. Edition III

    ERIC Educational Resources Information Center

    Rhode Island Department of Education, 2015

    2015-01-01

    Rhode Island educators believe that implementing a fair, accurate, and meaningful educator evaluation and support system will help improve teaching, learning, and school leadership. The primary purpose of the Rhode Island Model Building Administrator Evaluation and Support System (Rhode Island Model) is to help all building administrators improve.…

  2. Key Elements of the Tutorial Support Management Model

    ERIC Educational Resources Information Center

    Lynch, Grace; Paasuke, Philip

    2011-01-01

    In response to an exponential growth in enrolments the "Tutorial Support Management" (TSM) model has been adopted by Open Universities Australia (OUA) after a two-year project on the provision of online tutor support in first year, online undergraduate units. The essential focus of the TSM model was the development of a systemic approach to the…

  3. Model reduction for flexible structures

    NASA Technical Reports Server (NTRS)

    Gawronski, Wodek; Juang, Jer-Nan

    1990-01-01

    Several conditions for a near-optimal reduction of general dynamic systems are presented focusing on the reduction in balanced and modal coordinates. It is shown that model and balanced reductions give very different results for the flexible structure with closely-spaced natural frequencies. In general, balanced reduction is found to give better results. A robust model reduction technique was developed to study the sensitivity of modeling error to variations in the damping of a structure. New concepts of grammians defined over a finite time and/or a frequency interval are proposed including computational procedures for evaluating them. Application of the model reduction technique to these grammians is considered to lead to a near-optimal reduced model which closely reproduces the full system output in the time and/or frequency interval.

  4. Network model with structured nodes

    NASA Astrophysics Data System (ADS)

    Frisco, Pierluigi

    2011-08-01

    We present a network model in which words over a specific alphabet, called structures, are associated to each node and undirected edges are added depending on some distance measure between different structures. This model shifts the underlying principle of network generation from a purely mathematical one to an information-based one. It is shown how this model differs from the Barábasi-Albert and duplication models and how it can generate networks with topological features similar to biological networks: power law degree distribution, low average path length, clustering coefficient independent from the network size, etc. Two biological networks: S. cerevisiae gene network and E. coli protein-protein interaction network, are replicated using this model.

  5. Isolated catalyst sites on amorphous supports: A systematic algorithm for understanding heterogeneities in structure and reactivity

    NASA Astrophysics Data System (ADS)

    Goldsmith, Bryan R.; Sanderson, Evan D.; Bean, Daniel; Peters, Baron

    2013-05-01

    Methods for modeling catalytic sites on amorphous supports lag far behind methods for modeling catalytic sites on metal surfaces, zeolites, and other crystalline materials. One typical strategy for amorphous supports uses cluster models with arbitrarily chosen constraints to model the rigid amorphous support, but these constraints arbitrarily influence catalyst site activity. An alternative strategy is to use no constraints, but this results in catalytic sites with unrealistic flexibility. We present a systematic ab initio method to model isolated active sites on insulating amorphous supports using small cluster models. A sequential quadratic programming framework helps us relate chemical properties, such as the activation energy, to active site structure. The algorithm is first illustrated on an empirical valence bond model energy landscape. We then use the algorithm to model an off-pathway kinetic trap in olefin metathesis by isolated Mo sites on amorphous SiO2. The cluster models were terminated with basis set deficient fluorine atoms to mimic the properties of an extended silica framework. We also discuss limitations of the current algorithm formulation and future directions for improvement.

  6. The Qartaba Structure (Mount Lebanon): structural study and modeling

    NASA Astrophysics Data System (ADS)

    Asmar, Chloé; Grasemann, Bernhard; Tari, Gabor

    2014-05-01

    The prominent Qartaba Anticline is located on the western side of the northern Mount Lebanon, one of the major physiographic elements in Lebanon. The studied part of this anticline (~20 km long, ~5 km wide) represents a large-scale box-fold structure bounded by two SW- and NE-vergent monoclines. The aim of the structural study on the Qartaba Anticline was to get a better understanding on the poorly known mechanism and timing of folding of the structure. The main data elements used in this study included vintage geologic maps, very high-resolution satellite images, a satellite-based Digital Elevation Model and numerous field measurements taken during several field trips in the Mount Lebanon area. The database was incorporated into an ArcGis platform in order to carry out quantitative remote sensing analysis to have a better three-dimensional understanding of the geometry of the Qartaba structure and to model it. Using the Three-Point-Method that was developed on a MatLab platform and adapted into an ArcGis toolbox, it was possible to determine dip and dip direction of the folded strata of the Qartaba Structure in order to build additional input data points besides the field observations. The results from the ArcGis Model show that the eastern and western flanks of the anticline represent oppositely verging monoclines with average dip values increasing from about 15° at the outer limits of the structure to 30° closer to the center area and reaching values up to almost 90° at the steepest part of the eastern flank. The strata become more or less horizontal on the top of the structure, just a few hundred meters away from the limbs of the anticline. Therefore, the whole structure resembles a large scale box-fold. The structural model of the Qartaba Anticline presents new constraints on the timing and the mechanism of deformation of the structure. This new model has important implications for the tectonic evolution of Lebanon, for example, the footprint of the Syrian

  7. Model catalytic oxidation studies using supported monometallic and heterobimetallic oxides

    SciTech Connect

    Ekerdt, J.G.

    1992-02-03

    This research program is directed toward a more fundamental understanding of the effects of catalyst composition and structure on the catalytic properties of metal oxides. Metal oxide catalysts play an important role in many reactions bearing on the chemical aspects of energy processes. Metal oxides are the catalysts for water-gas shift reactions, methanol and higher alcohol synthesis, isosynthesis, selective catalytic reduction of nitric oxides, and oxidation of hydrocarbons. A key limitation to developing insight into how oxides function in catalytic reactions is in not having precise information of the surface composition under reaction conditions. To address this problem we have prepared oxide systems that can be used to study cation-cation effects and the role of bridging (-O-) and/or terminal (=O) surface oxygen anion ligands in a systematic fashion. Since many oxide catalyst systems involve mixtures of oxides, we selected a model system that would permit us to examine the role of each cation separately and in pairwise combinations. Organometallic molybdenum and tungsten complexes were proposed for use, to prepare model systems consisting of isolated monomeric cations, isolated monometallic dimers and isolated bimetallic dimers supported on silica and alumina. The monometallic and bimetallic dimers were to be used as models of more complex mixed- oxide catalysts. Our current program was to develop the systems and use them in model oxidation reactions.

  8. Pore structure characterization of catalyst supports via low field NMR

    SciTech Connect

    Smith, D.M.; Glaves, C.L.; Gallegos, D.P. )

    1988-09-01

    The pore structures of two types of catalyst support material were studied: {gamma}-alumina and silica aerogel. The alumina samples were commercial catalyst supports made in 1/8 inch diameter pellet form by Harshaw Chemical. Aerogels were prepared by forming a gel in a two-step, base-catalyzed process using TEOS, followed by supercritical drying to form the aerogel. Two different aerogels were made, one undergoing the drying process immediately after gel formation (non-aged), and the other being aged in the gel state for two weeks in a basic solution of 0.1 molar NH{sub 4}OH at 323 K before being supercritically dried (aged). The aging process is believed to alter the aerogel pore structure. The pore size distribution of the alumina material was determined via NMR and compared to results obtained by mercury intrusion and nitrogen adsorption/condensation techniques. The pore size distributions of the two aerogel samples were measured via NMR and nitrogen adsorption/condensation; the material was too compressible for porosimetry.

  9. 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

  10. Georeferenced model simulations efficiently support targeted monitoring

    NASA Astrophysics Data System (ADS)

    Berlekamp, Jürgen; Klasmeier, Jörg

    2010-05-01

    The European Water Framework Directive (WFD) demands the good ecological and chemical status of surface waters. To meet the definition of good chemical status of the WFD surface water concentrations of priority pollutants must not exceed established environmental quality standards (EQS). Surveillance of the concentrations of numerous chemical pollutants in whole river basins by monitoring is laborious and time-consuming. Moreover, measured data do often not allow for immediate source apportionment which is a prerequisite for defining promising reduction strategies to be implemented within the programme of measures. In this context, spatially explicit model approaches are highly advantageous because they provide a direct link between local point emissions (e.g. treated wastewater) or diffuse non-point emissions (e.g. agricultural runoff) and resulting surface water concentrations. Scenario analyses with such models allow for a priori investigation of potential positive effects of reduction measures such as optimization of wastewater treatment. The geo-referenced model GREAT-ER (Geography-referenced Regional Exposure Assessment Tool for European Rivers) has been designed to calculate spatially resolved averaged concentrations for different flow conditions (e.g. mean or low flow) based on emission estimations for local point source emissions such as treated effluents from wastewater treatment plants. The methodology was applied to selected pharmaceuticals (diclofenac, sotalol, metoprolol, carbamazepin) in the Main river basin in Germany (approx. 27,290 km²). Average concentrations of the compounds were calculated for each river reach in the whole catchment. Simulation results were evaluated by comparison with available data from orienting monitoring and used to develop an optimal monitoring strategy for the assessment of water quality regarding micropollutants at the catchment scale.

  11. Modelling structured data with Probabilistic Graphical Models

    NASA Astrophysics Data System (ADS)

    Forbes, F.

    2016-05-01

    Most clustering and classification methods are based on the assumption that the objects to be clustered are independent. However, in more and more modern applications, data are structured in a way that makes this assumption not realistic and potentially misleading. A typical example that can be viewed as a clustering task is image segmentation where the objects are the pixels on a regular grid and depend on neighbouring pixels on this grid. Also, when data are geographically located, it is of interest to cluster data with an underlying dependence structure accounting for some spatial localisation. These spatial interactions can be naturally encoded via a graph not necessarily regular as a grid. Data sets can then be modelled via Markov random fields and mixture models (e.g. the so-called MRF and Hidden MRF). More generally, probabilistic graphical models are tools that can be used to represent and manipulate data in a structured way while modeling uncertainty. This chapter introduces the basic concepts. The two main classes of probabilistic graphical models are considered: Bayesian networks and Markov networks. The key concept of conditional independence and its link to Markov properties is presented. The main problems that can be solved with such tools are described. Some illustrations are given associated with some practical work.

  12. Modelling of Geological Structures Using Emergence

    NASA Astrophysics Data System (ADS)

    Hillier, M.; de Kemp, E. A.; Sprague, K.

    2009-05-01

    A complex system based approach is used to model geological structures. Preliminary work is presented to show how mutually interacting agents can be used to probe local regions and obtain emergent behaviour of its geometrical properties. Models are built bottom up from the smaller components to simulate regions from camp scales to regional scales. In nature, very complex structures exhibiting discontinuous and heterogeneous features are common. Modelling such regions using conventional methods is cumbersome and influences between close proximity zones are generally not considered. Agents are able to detect local and global features in the entire model space, as detailed as the data set allows. These features are incorporated into the interpolation of a modeled zone if those features are coupled to that location. We attempt to see if opportunities exist for exploiting complex systems approaches in what is a classical knowledge driven modelling domain with high emphasis on expert interpretive methods. Geological maps (2D, 3D or 4D) are fundamentally an emergent result of an iterative mental process which focuses on reconciling disparate data. The end goal of our research is to point a way forward in which complexity can support the simulation of maps and thus support the interpretive workflow.

  13. [Coordinated organization of symptoms management and support in all the stages of cancer disease: putting in place pluridisciplinary structures of supportive oncological care].

    PubMed

    Krakowski, I; Chardot, C; Bey, P; Guillemin, F; Philip, T

    2001-03-01

    The organization of the management of pain and other symptoms all along the cancer disease, of psychological support and palliative care is a complex question that does not correspond to any perfectly established model, both in France and abroad. Different structures are implied in there care and coexist with an insufficient coordination: cancerology structures, structures of chronic pain management, structures of psycho-oncology, structures of palliative care. Some other assistances are more or less isolated inside the hospital: nutritional support, social assistance, action against tobacco and other addictions, volunteer work. Because of the evolution of practices and mentalities over the last ten years, the highlights of evident interfaces and complementary activities, the notions of "continuous care" and "integrated care" inside conventional departments, the budgetary and organizational restraints, it is now possible to propose a model of hospital structure adapted to the problem of supportive care. The creation is proposed from preexisting structures, consultations, units, departments of supportive oncological care according to the size of the institution. The structure should comply with some specifications, sometimes regulations, and to coordinate at best different competencies in the interest of the patients and medical teams : pain and symptoms management (of which palliative care is an important part), psycho-oncology, rehabilitation (functional rehabilitation, nutrition, social work, fights against addictions). A pooling of technology settings is one of its interest. The model can be applied in other domains than cancerology and in most health institutions. PMID:11313210

  14. Light scattering measurements supporting helical structures for chromatin in solution.

    PubMed

    Campbell, A M; Cotter, R I; Pardon, J F

    1978-05-01

    Laser light scattering measurements have been made on a series of polynucleosomes containing from 50 to 150 nucleosomes. Radii of gyration have been determined as a function of polynucleosome length for different ionic strength solutions. The results suggest that at low ionic strength the chromatin adopts a loosely helical structure rather than a random coil. The helix becomes more regular on increasing the ionic strength, the dimension resembling those proposed by Finch and Klug for their solenoid model. PMID:662693

  15. A longitudinal model of social contact, social support, depression, and alcohol use.

    PubMed

    Peirce, R S; Frone, M R; Russell, M; Cooper, M L; Mudar, P

    2000-01-01

    The longitudinal relations among contact with one's social network (social contact), perceived social support, depression, and alcohol use were examined. An integrative model was developed from affect regulation theory and theories of social support and dysfunctional drinking. Data were obtained from a random sample of 1,192 adults. The 3-wave panel model was tested using structural equation modeling analysis. Results revealed that (a) social contact was positively related to perceived social support; (b) perceived social support was, in turn, negatively related to depression; and (c) depression was, in turn, positively related to alcohol use for 1 of 2 longitudinal lags. There was partial support for the feedback hypothesis that increased alcohol use leads to decreased contact with family and friends. Although the results generally supported the authors' hypotheses, the significant coefficients in the model were generally small in size. PMID:10711585

  16. Supportive accountability: a model for providing human support to enhance adherence to eHealth interventions.

    PubMed

    Mohr, David C; Cuijpers, Pim; Lehman, Kenneth

    2011-01-01

    The effectiveness of and adherence to eHealth interventions is enhanced by human support. However, human support has largely not been manualized and has usually not been guided by clear models. The objective of this paper is to develop a clear theoretical model, based on relevant empirical literature, that can guide research into human support components of eHealth interventions. A review of the literature revealed little relevant information from clinical sciences. Applicable literature was drawn primarily from organizational psychology, motivation theory, and computer-mediated communication (CMC) research. We have developed a model, referred to as "Supportive Accountability." We argue that human support increases adherence through accountability to a coach who is seen as trustworthy, benevolent, and having expertise. Accountability should involve clear, process-oriented expectations that the patient is involved in determining. Reciprocity in the relationship, through which the patient derives clear benefits, should be explicit. The effect of accountability may be moderated by patient motivation. The more intrinsically motivated patients are, the less support they likely require. The process of support is also mediated by the communications medium (eg, telephone, instant messaging, email). Different communications media each have their own potential benefits and disadvantages. We discuss the specific components of accountability, motivation, and CMC medium in detail. The proposed model is a first step toward understanding how human support enhances adherence to eHealth interventions. Each component of the proposed model is a testable hypothesis. As we develop viable human support models, these should be manualized to facilitate dissemination. PMID:21393123

  17. Supportive Accountability: A Model for Providing Human Support to Enhance Adherence to eHealth Interventions

    PubMed Central

    2011-01-01

    The effectiveness of and adherence to eHealth interventions is enhanced by human support. However, human support has largely not been manualized and has usually not been guided by clear models. The objective of this paper is to develop a clear theoretical model, based on relevant empirical literature, that can guide research into human support components of eHealth interventions. A review of the literature revealed little relevant information from clinical sciences. Applicable literature was drawn primarily from organizational psychology, motivation theory, and computer-mediated communication (CMC) research. We have developed a model, referred to as “Supportive Accountability.” We argue that human support increases adherence through accountability to a coach who is seen as trustworthy, benevolent, and having expertise. Accountability should involve clear, process-oriented expectations that the patient is involved in determining. Reciprocity in the relationship, through which the patient derives clear benefits, should be explicit. The effect of accountability may be moderated by patient motivation. The more intrinsically motivated patients are, the less support they likely require. The process of support is also mediated by the communications medium (eg, telephone, instant messaging, email). Different communications media each have their own potential benefits and disadvantages. We discuss the specific components of accountability, motivation, and CMC medium in detail. The proposed model is a first step toward understanding how human support enhances adherence to eHealth interventions. Each component of the proposed model is a testable hypothesis. As we develop viable human support models, these should be manualized to facilitate dissemination. PMID:21393123

  18. Creating Shareable Clinical Decision Support Rules for a Pharmacogenomics Clinical Guideline Using Structured Knowledge Representation.

    PubMed

    Linan, Margaret K; Sottara, Davide; Freimuth, Robert R

    2015-01-01

    Pharmacogenomics (PGx) guidelines contain drug-gene relationships, therapeutic and clinical recommendations from which clinical decision support (CDS) rules can be extracted, rendered and then delivered through clinical decision support systems (CDSS) to provide clinicians with just-in-time information at the point of care. Several tools exist that can be used to generate CDS rules that are based on computer interpretable guidelines (CIG), but none have been previously applied to the PGx domain. We utilized the Unified Modeling Language (UML), the Health Level 7 virtual medical record (HL7 vMR) model, and standard terminologies to represent the semantics and decision logic derived from a PGx guideline, which were then mapped to the Health eDecisions (HeD) schema. The modeling and extraction processes developed here demonstrate how structured knowledge representations can be used to support the creation of shareable CDS rules from PGx guidelines. PMID:26958298

  19. Creating Shareable Clinical Decision Support Rules for a Pharmacogenomics Clinical Guideline Using Structured Knowledge Representation

    PubMed Central

    Linan, Margaret K.; Sottara, Davide; Freimuth, Robert R.

    2015-01-01

    Pharmacogenomics (PGx) guidelines contain drug-gene relationships, therapeutic and clinical recommendations from which clinical decision support (CDS) rules can be extracted, rendered and then delivered through clinical decision support systems (CDSS) to provide clinicians with just-in-time information at the point of care. Several tools exist that can be used to generate CDS rules that are based on computer interpretable guidelines (CIG), but none have been previously applied to the PGx domain. We utilized the Unified Modeling Language (UML), the Health Level 7 virtual medical record (HL7 vMR) model, and standard terminologies to represent the semantics and decision logic derived from a PGx guideline, which were then mapped to the Health eDecisions (HeD) schema. The modeling and extraction processes developed here demonstrate how structured knowledge representations can be used to support the creation of shareable CDS rules from PGx guidelines. PMID:26958298

  20. A model for effective planning of SME support services.

    PubMed

    Rakićević, Zoran; Omerbegović-Bijelović, Jasmina; Lečić-Cvetković, Danica

    2016-02-01

    This paper presents a model for effective planning of support services for small and medium-sized enterprises (SMEs). The idea is to scrutinize and measure the suitability of support services in order to give recommendations for the improvement of a support planning process. We examined the applied support services and matched them with the problems and needs of SMEs, based on the survey conducted in 2013 on a sample of 336 SMEs in Serbia. We defined and analysed the five research questions that refer to support services, their consistency with the SMEs' problems and needs, and the relation between the given support and SMEs' success. The survey results have shown a statistically significant connection between them. Based on this result, we proposed an eight-phase model as a method for the improvement of support service planning for SMEs. This model helps SMEs to plan better their requirements in terms of support; government and administration bodies at all levels and organizations that provide support services to understand better SMEs' problems and needs for support. PMID:26479837

  1. Comparing composite materials with structural steels in the design of the optical support structure of very large telescopes

    NASA Astrophysics Data System (ADS)

    Cheng, Andrew Y.; Li, Robert K.

    1992-03-01

    The method of finite element analysis is used to study some candidate composite materials: carbon filter reinforced epoxy and glass fiber reinforced epoxy. These composites may have real applications in the design of the optical support structures of very large telescopes where stringent thermomechanical stability are needed. The lightweight property of these materials allows one to build very stiff members for the optical support to withstand the structural deflections due to wind, vibration, and gravity. We have run finite element models of these composites using ABAQUS on a VAX VMS computer. Simple beams with rectangular cross- sections were computed for the composites with structural steel as a comparison. The static properties of these beams were studied.

  2. Multiple lesion track structure model

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Cucinotta, Francis A.; Shinn, Judy L.

    1992-01-01

    A multilesion cell kinetic model is derived, and radiation kinetic coefficients are related to the Katz track structure model. The repair-related coefficients are determined from the delayed plating experiments of Yang et al. for the C3H10T1/2 cell system. The model agrees well with the x ray and heavy ion experiments of Yang et al. for the immediate plating, delaying plating, and fractionated exposure protocols employed by Yang. A study is made of the effects of target fragments in energetic proton exposures and of the repair-deficient target-fragment-induced lesions.

  3. Plasma growth hormones, P300 event-related potential and test of variables of attention (TOVA) are important neuroendocrinological predictors of early cognitive decline in a clinical setting: Evidence supported by structural equation modeling (SEM) parameter estimates

    PubMed Central

    Braverman, Eric R.; Chen, Thomas J. H.; Prihoda, Thomas J.; Sonntag, William; Meshkin, Brian; Downs, B. William; Mengucci, Julie F.; Blum, Seth H.; Notaro, Alison; Arcuri, Vanessa; Varshavskiy, Michael

    2007-01-01

    A review of the literature in both animals and humans reveals that changes in sex hormone have often been associated with changes in behavioral and mental abilities. Previously published research from our laboratory, and others, provides strong evidence that P300 (latency) event-related potential (ERP), a marker of neuronal processing speed, is an accurate predictor of early memory impairment in both males and females across a wide age range. It is our hypothesis, given the vast literature on the subject, that coupling growth hormones (insulin-like growth factor-I, (IGF-I) and insulin-like growth factor binding protein 3 (IGF-BP3)), P300 event-related potential and test of variables of attention (TOVA) are important neuroendocrinological predictors of early cognitive decline in a clinical setting. To support this hypothesis, we utilized structural equation modeling (SEM) parameter estimates to determine the relationship between aging and memory, as mediated by growth hormone (GH) levels (indirectly measured through the insulin-like growth factor system), P300 latency and TOVA, putative neurocognitive predictors tested in this study. An SEM was developed hypothesizing a causal directive path, leading from age to memory, mediated by IGF-1 and IGF-BP3, P300 latency (speed), and TOVA decrements. An increase in age was accompanied by a decrease in IGF-1 and IGF-BP3, an increase in P300 latency, a prolongation in TOVA response time, and a decrease in memory functioning. Moreover, independent of age, decreases in IGF-1 and IGF-BP3, were accompanied by increases in P300 latency, and were accompanied by increases in TOVA response time. Finally, increases in P300 latency were accompanied by decreased memory function, both directly and indirectly through mediation of TOVA response time. In summary, this is the first report utilizing SEM to reveal the finding that aging affects memory function negatively through mediation of decreased IGF-1 and IGF-BP3, and increased P300

  4. Plasma growth hormones, P300 event-related potential and test of variables of attention (TOVA) are important neuroendocrinological predictors of early cognitive decline in a clinical setting: evidence supported by structural equation modeling (SEM) parameter estimates.

    PubMed

    Braverman, Eric R; Chen, Thomas J H; Prihoda, Thomas J; Sonntag, William; Meshkin, Brian; Downs, B William; Mengucci, Julie F; Blum, Seth H; Notaro, Alison; Arcuri, Vanessa; Varshavskiy, Michael; Blum, Kenneth

    2007-09-01

    A review of the literature in both animals and humans reveals that changes in sex hormone have often been associated with changes in behavioral and mental abilities. Previously published research from our laboratory, and others, provides strong evidence that P300 (latency) event-related potential (ERP), a marker of neuronal processing speed, is an accurate predictor of early memory impairment in both males and females across a wide age range. It is our hypothesis, given the vast literature on the subject, that coupling growth hormones (insulin-like growth factor-I, (IGF-I) and insulin-like growth factor binding protein 3 (IGF-BP3)), P300 event-related potential and test of variables of attention (TOVA) are important neuroendocrinological predictors of early cognitive decline in a clinical setting. To support this hypothesis, we utilized structural equation modeling (SEM) parameter estimates to determine the relationship between aging and memory, as mediated by growth hormone (GH) levels (indirectly measured through the insulin-like growth factor system), P300 latency and TOVA, putative neurocognitive predictors tested in this study. An SEM was developed hypothesizing a causal directive path, leading from age to memory, mediated by IGF-1 and IGF-BP3, P300 latency (speed), and TOVA decrements. An increase in age was accompanied by a decrease in IGF-1 and IGF-BP3, an increase in P300 latency, a prolongation in TOVA response time, and a decrease in memory functioning. Moreover, independent of age, decreases in IGF-1 and IGF-BP3, were accompanied by increases in P300 latency, and were accompanied by increases in TOVA response time. Finally, increases in P300 latency were accompanied by decreased memory function, both directly and indirectly through mediation of TOVA response time. In summary, this is the first report utilizing SEM to reveal the finding that aging affects memory function negatively through mediation of decreased IGF-1 and IGF-BP3, and increased P300

  5. Supporting and structuring "contributing student pedagogy" in Computer Science curricula

    NASA Astrophysics Data System (ADS)

    Falkner, Katrina; Falkner, Nickolas J. G.

    2012-12-01

    Contributing student pedagogy (CSP) builds upon social constructivist and community-based learning principles to create engaging and productive learning experiences. What makes CSP different from other, related, learning approaches is that it involves students both learning from and also explicitly valuing the contributions of other students. The creation of such a learning community builds upon established educational psychology that encourages deep learning, reflection and engagement. Our school has recently completed a review and update of its curriculum, incorporating student content-creation and collaboration into the design of key courses across the curriculum. Our experiences, based on several years of experimentation and development, support CSP-based curriculum design to reinforce the value of the student perspective, the clear description of their own transformative pathway to knowledge and the importance of establishing student-to-student networks in which students are active and willing participants. In this paper, we discuss the tools and approaches that we have employed to guide, support and structure student collaboration across a range of courses and year levels. By providing an account of our intentions, our approaches and tools, we hope to provide useful and transferrable knowledge that can be readily used by other academics who are considering this approach.

  6. Crankshaft supporting structure for multicylinder internal combustion engines

    SciTech Connect

    Fukuo, K.; Chosa, M.

    1988-01-26

    A crankshaft supporting structure for a cylinder block of an internal combustion engine is described, comprising, journal walls extending laterally across the cylinder block and being longitudinally spaced along the crankshaft, a recess formed in each journal wall with inwardly and downwardly facing first mating surfaces at an upper extremity of the recess. The cylinder block has skirt portions extending downwardly from the recesses on each lateral end of the journal walls, a bearing cap mounted in the recess in each journal wall and having means cooperating with the journal wall for rotatably supporting the crankshaft, each bearing cap having outwardly and upwardly facing first mating surfaces for engaging the journal wall first mating surfaces, mating inwardly facing vertical surfaces on each skirt portion and outwardly facing vertical surfaces on each bearing cap, a longitudinally extending bridge, a pair of vertical bolts extending through the bridge and each bearing cap and threadedly engaging the journal wall, horizontal bolts extending through the skirt portions and threadedly engaging each lateral side of each bearing cap, and the bridge having a main oil gallery defined therein for passage of lubricating oil therethrough and communicating with lubricating oil passages formed through the bridge and the bearing caps for communicating oil to the crankshaft.

  7. Semantic Web Infrastructure Supporting NextFrAMES Modeling Platform

    NASA Astrophysics Data System (ADS)

    Lakhankar, T.; Fekete, B. M.; Vörösmarty, C. J.

    2008-12-01

    Emerging modeling frameworks offer new ways to modelers to develop model applications by offering a wide range of software components to handle common modeling tasks such as managing space and time, distributing computational tasks in parallel processing environment, performing input/output and providing diagnostic facilities. NextFrAMES, the next generation updates to the Framework for Aquatic Modeling of the Earth System originally developed at University of New Hampshire and currently hosted at The City College of New York takes a step further by hiding most of these services from modeler behind a platform agnostic modeling platform that allows scientists to focus on the implementation of scientific concepts in the form of a new modeling markup language and through a minimalist application programming interface that provide means to implement model processes. At the core of the NextFrAMES modeling platform there is a run-time engine that interprets the modeling markup language loads the module plugins establishes the model I/O and executes the model defined by the modeling XML and the accompanying plugins. The current implementation of the run-time engine is designed for single processor or symmetric multi processing (SMP) systems but future implementation of the run-time engine optimized for different hardware architectures are anticipated. The modeling XML and the accompanying plugins define the model structure and the computational processes in a highly abstract manner, which is not only suitable for the run-time engine, but has the potential to integrate into semantic web infrastructure, where intelligent parsers can extract information about the model configurations such as input/output requirements applicable space and time scales and underlying modeling processes. The NextFrAMES run-time engine itself is also designed to tap into web enabled data services directly, therefore it can be incorporated into complex workflow to implement End-to-End application

  8. Structures in Molecular Clouds: Modeling

    SciTech Connect

    Kane, J O; Mizuta, A; Pound, M W; Remington, B A; Ryutov, D D

    2006-04-20

    We attempt to predict the observed morphology, column density and velocity gradient of Pillar II of the Eagle Nebula, using Rayleigh Taylor (RT) models in which growth is seeded by an initial perturbation in density or in shape of the illuminated surface, and cometary models in which structure is arises from a initially spherical cloud with a dense core. Attempting to mitigate suppression of RT growth by recombination, we use a large cylindrical model volume containing the illuminating source and the self-consistently evolving ablated outflow and the photon flux field, and use initial clouds with finite lateral extent. An RT model shows no growth, while a cometary model appears to be more successful at reproducing observations.

  9. Design and analysis of supporting structure between the primary mirror and the secondary mirror on a space telescope

    NASA Astrophysics Data System (ADS)

    Wang, Chenjie; Chai, Wenyi; Feng, Liangjie; Yang, Wengang; Wang, Wei; Fan, Xuewu

    2015-10-01

    Mechanical stability is a significant segment for an on-axis space telescope to assure its assembly accuracy as well as the image quality in the rigorous space environment, supporting structure between the primary mirror and the secondary mirror as a main structure of the on-axis space telescope must be designed reasonably to meet the mission requirements of the space telescope. Meanwhile, in view of the limitation of the satellite launching cost, it is necessary to reduce the weight and power compensation during the supporting structure design based on the satisfaction of telescope performance. Two types of supporting structure for a space telescope are designed, one is three-tripod structure which has three tripods located on the optical bench to support the secondary mirror assemblies and keep the distance between the primary mirror and the secondary mirror, the other is barrel supporting structure which includes a tube and a secondary mirror support with four spider struts. To compare the mechanical performance and launching cost of the two kinds of supporting structure, both structural and thermal analysis model are established. The analysis results indicates that the three-tripod support is lighter, has better mechanical performance and needs less power compensation than the barrel support.

  10. Supports and modified nano-particles for designing model catalysts.

    PubMed

    O'Brien, C P; Dostert, K-H; Hollerer, M; Stiehler, C; Calaza, F; Schauermann, S; Shaikhutdinov, S; Sterrer, M; Freund, H-J

    2016-07-01

    In order to design catalytic materials, we need to understand the essential causes for material properties resulting from its composite nature. In this paper we discuss two, at first sight, diverse aspects: (a) the effect of the oxide-metal interface on metal nanoparticle properties and (b) the consequences of metal particle modification after activation on the selectivity of hydrogenation reactions. However, these two aspects are intimately linked. The metal nanoparticle's electronic structure changes at the interface as a catalyst is brought to different reaction temperatures due to morphological modifications in the metal and, as we will discuss, these changes in the chemistry lead to changes in the reaction path. As the morphology of the particle varies, facets of different orientations and sizes are exposed, which may lead to a change in the surface chemistry as well. We use two specific reactions to address these issues in some detail. To the best of our knowledge, the present paper reports the first observations of this kind for well-defined model systems. The changes in the electronic structure of Au nanoparticles due to their size and interaction with a supporting oxide are revealed as a function of temperature using CO2 activation as a probe. The presence of spectator species (oxopropyl), formed during an activation step of acrolein hydrogenation, strongly controls the selectivity of the reaction towards hydrogenation of the unsaturated C[double bond, length as m-dash]O bond vs. the C[double bond, length as m-dash]C bond on Pd(111) when compared with oxide-supported Pd nanoparticles. PMID:27064816

  11. Object-oriented structures supporting remote sensing databases

    NASA Technical Reports Server (NTRS)

    Wichmann, Keith; Cromp, Robert F.

    1995-01-01

    Object-oriented databases show promise for modeling the complex interrelationships pervasive in scientific domains. To examine the utility of this approach, we have developed an Intelligent Information Fusion System based on this technology, and applied it to the problem of managing an active repository of remotely-sensed satellite scenes. The design and implementation of the system is compared and contrasted with conventional relational database techniques, followed by a presentation of the underlying object-oriented data structures used to enable fast indexing into the data holdings.

  12. Track structure in biological models.

    PubMed

    Curtis, S B

    1986-01-01

    High-energy heavy ions in the galactic cosmic radiation (HZE particles) may pose a special risk during long term manned space flights outside the sheltering confines of the earth's geomagnetic field. These particles are highly ionizing, and they and their nuclear secondaries can penetrate many centimeters of body tissue. The three dimensional patterns of ionizations they create as they lose energy are referred to as their track structure. Several models of biological action on mammalian cells attempt to treat track structure or related quantities in their formulation. The methods by which they do this are reviewed. The proximity function is introduced in connection with the theory of Dual Radiation Action (DRA). The ion-gamma kill (IGK) model introduces the radial energy-density distribution, which is a smooth function characterizing both the magnitude and extension of a charged particle track. The lethal, potentially lethal (LPL) model introduces lambda, the mean distance between relevant ion clusters or biochemical species along the track. Since very localized energy depositions (within approximately 10 nm) are emphasized, the proximity function as defined in the DRA model is not of utility in characterizing track structure in the LPL formulation. PMID:11537218

  13. Lunar Polar Illumination Modeling to Support Data Analysis

    NASA Astrophysics Data System (ADS)

    Mazarico, E.; Nicholas, J. B.; McClanahan, T. P.; Neumann, G. A.

    2014-10-01

    We show that illumination modeling at the lunar poles can be useful to support calibration and analysis of lunar datasets such as the neutron data, in particular when studying time­variable effects and correlation with time of day.

  14. How can models support a transition to sustainability: The role of simulations in sustainable resource management

    NASA Astrophysics Data System (ADS)

    Halbe, Johannes; Reusser, Dominik E.; Holtz, Gerog; Stosius, Annette; Kwakkel, Jan; Haasnoot, Marjolijn; Avenhaus, Wiebke

    2013-04-01

    The delineation of transition pathways towards sustainability and the implementation of associated measures are challenged by uncertainty, structural barriers, and conflicts among affected stakeholders. Experiences from other research domains suggest that the effective application of models to tackle these challenges require the explicit consideration of modeling purposes and roles. We present a classification of modeling roles for the analysis and governance of transitions. Models can support understanding of transitions processes, detect barriers and drivers of change, support the exploration of pathways towards sustainability, and help to actively engage relevant stakeholder groups. For each application area, examples are provided from the transition community and related research fields like environmental modeling and integrated assessment.

  15. Overcoming barriers to development of cooperative medical decision support models.

    PubMed

    Hudson, Donna L; Cohen, Maurice E

    2012-01-01

    Attempts to automate the medical decision making process have been underway for the at least fifty years, beginning with data-based approaches that relied chiefly on statistically-based methods. Approaches expanded to include knowledge-based systems, both linear and non-linear neural networks, agent-based systems, and hybrid methods. While some of these models produced excellent results none have been used extensively in medical practice. In order to move these methods forward into practical use, a number of obstacles must be overcome, including validation of existing systems on large data sets, development of methods for including new knowledge as it becomes available, construction of a broad range of decision models, and development of non-intrusive methods that allow the physician to use these decision aids in conjunction with, not instead of, his or her own medical knowledge. None of these four requirements will come easily. A cooperative effort among researchers, including practicing MDs, is vital, particularly as more information on diseases and their contributing factors continues to expand resulting in more parameters than the human decision maker can process effectively. In this article some of the basic structures that are necessary to facilitate the use of an automated decision support system are discussed, along with potential methods for overcoming existing barriers. PMID:23366358

  16. The Chemical Composition and Structure of Supported Sulfated Zirconia with Regulated Size Nanoparticles

    NASA Astrophysics Data System (ADS)

    Kanazhevskiy, V. V.; Shmachkova, V. P.; Kotsarenko, N. S.; Kochubey, D. I.; Vedrine, J. C.

    2007-02-01

    A set of model skeletal isomerization catalysts — sulfated zirconia nanoparticles of controlled thickness anchored on different supports — was prepared using colloidal solutions of Zr salt on titania as support. The nanoparticles of zirconia (1-5 nm) are epitaxially connected to the support surface, with S/Zr ratio equals to 1.3-1.5. It was shown by EXAFS that nanoparticles of non-stoichiometric zirconium sulfate Zr(SO4)1+x, where x<0.5, are formed on the support surface. Its structure looks like half-period shifted counterdirected chains built-up by zirconium atoms linked by triangle pyramids of sulfate groups. Considering catalytic data of skeletal n-butane isomerisation at 150°C, one can suggest that these species behave as the active component of sulfated zirconia. They are formed in subsurface layers as zirconium hydroxide undergoes sulfation followed by thermal treatment.

  17. A Framework and Model for Evaluating Clinical Decision Support Architectures

    PubMed Central

    Wright, Adam; Sittig, Dean F.

    2008-01-01

    In this paper, we develop a four-phase model for evaluating architectures for clinical decision support that focuses on: defining a set of desirable features for a decision support architecture; building a proof-of-concept prototype; demonstrating that the architecture is useful by showing that it can be integrated with existing decision support systems and comparing its coverage to that of other architectures. We apply this framework to several well-known decision support architectures, including Arden Syntax, GLIF, SEBASTIAN and SAGE PMID:18462999

  18. Structure and modeling of turbulence

    SciTech Connect

    Novikov, E.A.

    1995-12-31

    The {open_quotes}vortex strings{close_quotes} scale l{sub s} {approximately} LRe{sup -3/10} (L-external scale, Re - Reynolds number) is suggested as a grid scale for the large-eddy simulation. Various aspects of the structure of turbulence and subgrid modeling are described in terms of conditional averaging, Markov processes with dependent increments and infinitely divisible distributions. The major request from the energy, naval, aerospace and environmental engineering communities to the theory of turbulence is to reduce the enormous number of degrees of freedom in turbulent flows to a level manageable by computer simulations. The vast majority of these degrees of freedom is in the small-scale motion. The study of the structure of turbulence provides a basis for subgrid-scale (SGS) models, which are necessary for the large-eddy simulations (LES).

  19. Structural dynamic and thermal stress analysis of nuclear reactor vessel support system

    NASA Technical Reports Server (NTRS)

    Chi-Diango, J.

    1972-01-01

    A nuclear reactor vessel is supported by a Z-ring and a box ring girder. The two proposed structural configurations to transmit the loads from the Z-ring and the box ring girder to the foundation are shown. The cantilever concrete ledge transmitting the load from the Z-ring and the box girder via the cavity wall to the foundation is shown, along with the loads being transmitted through one of the six steel columns. Both of these two supporting systems were analyzed by using rigid format 9 of NASTRAN for dynamic loads, and the thermal stresses were analyzed by AXISOL. The six column configuration was modeled by a combination of plate and bar elements, and the concrete cantilever ledge configuration was modeled by plate elements. Both configurations were found structurally satisfactory; however, nonstructural considerations favored the concrete cantilever ledge.

  20. Data publication with the structural biology data grid supports live analysis.

    PubMed

    Meyer, Peter A; Socias, Stephanie; Key, Jason; Ransey, Elizabeth; Tjon, Emily C; Buschiazzo, Alejandro; Lei, Ming; Botka, Chris; Withrow, James; Neau, David; Rajashankar, Kanagalaghatta; Anderson, Karen S; Baxter, Richard H; Blacklow, Stephen C; Boggon, Titus J; Bonvin, Alexandre M J J; Borek, Dominika; Brett, Tom J; Caflisch, Amedeo; Chang, Chung-I; Chazin, Walter J; Corbett, Kevin D; Cosgrove, Michael S; Crosson, Sean; Dhe-Paganon, Sirano; Di Cera, Enrico; Drennan, Catherine L; Eck, Michael J; Eichman, Brandt F; Fan, Qing R; Ferré-D'Amaré, Adrian R; Christopher Fromme, J; Garcia, K Christopher; Gaudet, Rachelle; Gong, Peng; Harrison, Stephen C; Heldwein, Ekaterina E; Jia, Zongchao; Keenan, Robert J; Kruse, Andrew C; Kvansakul, Marc; McLellan, Jason S; Modis, Yorgo; Nam, Yunsun; Otwinowski, Zbyszek; Pai, Emil F; Pereira, Pedro José Barbosa; Petosa, Carlo; Raman, C S; Rapoport, Tom A; Roll-Mecak, Antonina; Rosen, Michael K; Rudenko, Gabby; Schlessinger, Joseph; Schwartz, Thomas U; Shamoo, Yousif; Sondermann, Holger; Tao, Yizhi J; Tolia, Niraj H; Tsodikov, Oleg V; Westover, Kenneth D; Wu, Hao; Foster, Ian; Fraser, James S; Maia, Filipe R N C; Gonen, Tamir; Kirchhausen, Tom; Diederichs, Kay; Crosas, Mercè; Sliz, Piotr

    2016-01-01

    Access to experimental X-ray diffraction image data is fundamental for validation and reproduction of macromolecular models and indispensable for development of structural biology processing methods. Here, we established a diffraction data publication and dissemination system, Structural Biology Data Grid (SBDG; data.sbgrid.org), to preserve primary experimental data sets that support scientific publications. Data sets are accessible to researchers through a community driven data grid, which facilitates global data access. Our analysis of a pilot collection of crystallographic data sets demonstrates that the information archived by SBDG is sufficient to reprocess data to statistics that meet or exceed the quality of the original published structures. SBDG has extended its services to the entire community and is used to develop support for other types of biomedical data sets. It is anticipated that access to the experimental data sets will enhance the paradigm shift in the community towards a much more dynamic body of continuously improving data analysis. PMID:26947396

  1. Data publication with the structural biology data grid supports live analysis

    PubMed Central

    Meyer, Peter A.; Socias, Stephanie; Key, Jason; Ransey, Elizabeth; Tjon, Emily C.; Buschiazzo, Alejandro; Lei, Ming; Botka, Chris; Withrow, James; Neau, David; Rajashankar, Kanagalaghatta; Anderson, Karen S.; Baxter, Richard H.; Blacklow, Stephen C.; Boggon, Titus J.; Bonvin, Alexandre M. J. J.; Borek, Dominika; Brett, Tom J.; Caflisch, Amedeo; Chang, Chung-I; Chazin, Walter J.; Corbett, Kevin D.; Cosgrove, Michael S.; Crosson, Sean; Dhe-Paganon, Sirano; Di Cera, Enrico; Drennan, Catherine L.; Eck, Michael J.; Eichman, Brandt F.; Fan, Qing R.; Ferré-D'Amaré, Adrian R.; Christopher Fromme, J.; Garcia, K. Christopher; Gaudet, Rachelle; Gong, Peng; Harrison, Stephen C.; Heldwein, Ekaterina E.; Jia, Zongchao; Keenan, Robert J.; Kruse, Andrew C.; Kvansakul, Marc; McLellan, Jason S.; Modis, Yorgo; Nam, Yunsun; Otwinowski, Zbyszek; Pai, Emil F.; Pereira, Pedro José Barbosa; Petosa, Carlo; Raman, C. S.; Rapoport, Tom A.; Roll-Mecak, Antonina; Rosen, Michael K.; Rudenko, Gabby; Schlessinger, Joseph; Schwartz, Thomas U.; Shamoo, Yousif; Sondermann, Holger; Tao, Yizhi J.; Tolia, Niraj H.; Tsodikov, Oleg V.; Westover, Kenneth D.; Wu, Hao; Foster, Ian; Fraser, James S.; Maia, Filipe R. N C.; Gonen, Tamir; Kirchhausen, Tom; Diederichs, Kay; Crosas, Mercè; Sliz, Piotr

    2016-01-01

    Access to experimental X-ray diffraction image data is fundamental for validation and reproduction of macromolecular models and indispensable for development of structural biology processing methods. Here, we established a diffraction data publication and dissemination system, Structural Biology Data Grid (SBDG; data.sbgrid.org), to preserve primary experimental data sets that support scientific publications. Data sets are accessible to researchers through a community driven data grid, which facilitates global data access. Our analysis of a pilot collection of crystallographic data sets demonstrates that the information archived by SBDG is sufficient to reprocess data to statistics that meet or exceed the quality of the original published structures. SBDG has extended its services to the entire community and is used to develop support for other types of biomedical data sets. It is anticipated that access to the experimental data sets will enhance the paradigm shift in the community towards a much more dynamic body of continuously improving data analysis. PMID:26947396

  2. New approach to the design of core support structures for large LMFBR plants

    SciTech Connect

    Burelbach, J.P.; Kann, W.J.; Pan, Y.C.; Saiveau, J.G.; Seidensticker, R.W.

    1984-01-01

    The paper describes an innovative design concept for a LMFBR Core Support Structure. A hanging Core Support Structure is described and analyzed. The design offers inherent safety features, constructibility advantages, and potential cost reductions.

  3. Controllable occurrence of free-standing lipid membranes on nanograting structured supports.

    PubMed

    Peng, Po-Yu; Chiang, Po-Chieh; Chao, Ling

    2014-08-13

    Supported lipid bilayers (SLBs) have been widely used to study protein-lipid membrane interactions because their planar geometry is suitable for many surface analysis tools. However, the friction coupling between the support and the membrane can influence the properties of biomolecules in the membrane. Many studies have attempted to span SLBs over nanostructured supports to create free-standing regions in SLBs for biosensor applications. However, membranes following the support surface contour are more frequently observed than are free-standing membranes on structured supports, indicating that the parameter range suitable for formation of free-standing SLBs might be narrow and more information is necessary to understand the required conditions. The objective of this study was to estimate the system energies of free-standing and contour-following membrane states and determine which state is the most energetically favorable under various conditions. For a lipid membrane preferring to stay close to the support, an energy reward occurs when they are in close proximity; however, increasing the contact area on a structured surface can result in an energy penalty because of the bending of the lipid bilayer. Whether the energy reward or the energy penalty dominates could determine the membrane state. We used the extended Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and the Helfrich bending theory to relate the energy sizes to experimentally controllable parameters. We experimentally examined whether the membrane state followed the model prediction when we used various buffer ionic strengths, various lipid types, and nanograting supports with three different geometries. Because it is difficult to observe the experimental membrane state directly at the nanoscale, we developed a method to use the fluorescence recovery shape change after photobleaching to distinguish experimental membrane states at the micrometer scale. Our experimental results closely matched the

  4. Support System Effects on the NASA Common Research Model

    NASA Technical Reports Server (NTRS)

    Rivers, S. Melissa B.; Hunter, Craig A.

    2012-01-01

    An experimental investigation of the NASA Common Research Model was conducted in the NASA Langley National Transonic Facility and NASA Ames 11-Foot Transonic Wind Tunnel Facility for use in the Drag Prediction Workshop. As data from the experimental investigations was collected, a large difference in moment values was seen between the experimental and the computational data from the 4th Drag Prediction Workshop. This difference led to the present work. In this study, a computational assessment has been undertaken to investigate model support system interference effects on the Common Research Model. The configurations computed during this investigation were the wing/body/tail=0deg without the support system and the wing/body/tail=0deg with the support system. The results from this investigation confirm that the addition of the support system to the computational cases does shift the pitching moment in the direction of the experimental results.

  5. Error Location in Structural Dynamic Model of a Rocket Structure

    NASA Astrophysics Data System (ADS)

    Sundararajan, T.; Sam, C.

    2012-06-01

    Structural dynamic characteristics of the aerospace structures are essential to obtain the structural responses due to dynamic loads during its mission. The structural dynamic parameters of the aerospace structures are frequencies, associated mode shape and damping. Usually finite element (FE) model of the aerospace structures are generated to estimate the frequencies and the associated mode shape. These FE models are validated by modal survey/ground resonance tests to ensure its completeness and correctness. The modeling deficiencies, if any, in these FE models have to be corrected. This paper describes the method to locate the FE modeling errors using residual force method.

  6. Atomic Resolution of the Structure of a Metal Support Interface: Triosmium Clusters on MgO (110)

    SciTech Connect

    Browning, Nigel D.; Chi, Miaofang; Gates, Bruce C.; kulkarni, Apoorva; Ortalan, Volkan

    2010-01-01

    Aberration-corrected STEM images of MgO-supported triosmium clusters show that the osmium atoms reside atop magnesium atoms. On the basis of the results, structural models of the clusters that include the metal-support interaction are derived.

  7. Support structures for optical components in the Laser Demonstration Facility

    SciTech Connect

    Finucane, R.G.

    1985-01-25

    The laser system in the Laser Demonstration Facility is mounted on an array of 108 support columns. This milestone report describes the design, analyses, testing, fabrication, installation, and performance characteristics of these supports.

  8. Snow Micro-Structure Model

    Energy Science and Technology Software Center (ESTSC)

    2014-06-25

    PIKA is a MOOSE-based application for modeling micro-structure evolution of seasonal snow. The model will be useful for environmental, atmospheric, and climate scientists. Possible applications include application to energy balance models, ice sheet modeling, and avalanche forecasting. The model implements physics from published, peer-reviewed articles. The main purpose is to foster university and laboratory collaboration to build a larger multi-scale snow model using MOOSE. The main feature of the code is that it is implementedmore » using the MOOSE framework, thus making features such as multiphysics coupling, adaptive mesh refinement, and parallel scalability native to the application. PIKA implements three equations: the phase-field equation for tracking the evolution of the ice-air interface within seasonal snow at the grain-scale; the heat equation for computing the temperature of both the ice and air within the snow; and the mass transport equation for monitoring the diffusion of water vapor in the pore space of the snow.« less

  9. Snow Micro-Structure Model

    SciTech Connect

    Micah Johnson, Andrew Slaughter

    2014-06-25

    PIKA is a MOOSE-based application for modeling micro-structure evolution of seasonal snow. The model will be useful for environmental, atmospheric, and climate scientists. Possible applications include application to energy balance models, ice sheet modeling, and avalanche forecasting. The model implements physics from published, peer-reviewed articles. The main purpose is to foster university and laboratory collaboration to build a larger multi-scale snow model using MOOSE. The main feature of the code is that it is implemented using the MOOSE framework, thus making features such as multiphysics coupling, adaptive mesh refinement, and parallel scalability native to the application. PIKA implements three equations: the phase-field equation for tracking the evolution of the ice-air interface within seasonal snow at the grain-scale; the heat equation for computing the temperature of both the ice and air within the snow; and the mass transport equation for monitoring the diffusion of water vapor in the pore space of the snow.

  10. Are Tornado-Like Magnetic Structures Able to Support Solar Prominence Plasma?

    NASA Astrophysics Data System (ADS)

    Ogunjo, S. T.; Luna Bennasar, M.; Moreno-Insertis, F.; Priest, E. R.

    2015-12-01

    Recent high-resolution and high-cadence observations have surprisingly suggested that prominence barbs exhibit apparent rotating motions suggestive of a tornado-like structure. Additional evidence has been provided by Doppler measurements. The observations reveal opposite velocities for both hot and cool plasma on the two sides of a prominence barb. This motion is persistent for several hours and has been interpreted in terms of rotational motion of prominence feet. Several authors suggest that such barb motions are rotating helical structures around a vertical axis similar to tornadoes on Earth. One of the difficulties of such a proposal is how to support cool prominence plasma in almost-vertical structures against gravity. In this work we model analytically a tornado-like structure and try to determine possible mechanisms to support the prominence plasma. We have found that the Lorentz force can indeed support the barb plasma provided the magnetic structure is sufficiently twisted and/or significant poloidal flows are present.

  11. Are Tornado-like Magnetic Structures Able to Support Solar Prominence Plasma?

    NASA Astrophysics Data System (ADS)

    Luna, M.; Moreno-Insertis, F.; Priest, E.

    2015-07-01

    Recent high-resolution and high-cadence observations have surprisingly suggested that prominence barbs exhibit apparent rotating motions suggestive of a tornado-like structure. Additional evidence has been provided by Doppler measurements. The observations reveal opposite velocities for both hot and cool plasma on the two sides of a prominence barb. This motion is persistent for several hours and has been interpreted in terms of rotational motion of prominence feet. Several authors suggest that such barb motions are rotating helical structures around a vertical axis similar to tornadoes on Earth. One of the difficulties of such a proposal is how to support cool prominence plasma in almost-vertical structures against gravity. In this work we model analytically a tornado-like structure and try to determine possible mechanisms to support the prominence plasma. We have found that the Lorentz force can indeed support the barb plasma provided the magnetic structure is sufficiently twisted and/or significant poloidal flows are present.

  12. Using support vector machines to improve elemental ion identification in macromolecular crystal structures

    SciTech Connect

    Morshed, Nader; Echols, Nathaniel; Adams, Paul D.

    2015-05-01

    A method to automatically identify possible elemental ions in X-ray crystal structures has been extended to use support vector machine (SVM) classifiers trained on selected structures in the PDB, with significantly improved sensitivity over manually encoded heuristics. In the process of macromolecular model building, crystallographers must examine electron density for isolated atoms and differentiate sites containing structured solvent molecules from those containing elemental ions. This task requires specific knowledge of metal-binding chemistry and scattering properties and is prone to error. A method has previously been described to identify ions based on manually chosen criteria for a number of elements. Here, the use of support vector machines (SVMs) to automatically classify isolated atoms as either solvent or one of various ions is described. Two data sets of protein crystal structures, one containing manually curated structures deposited with anomalous diffraction data and another with automatically filtered, high-resolution structures, were constructed. On the manually curated data set, an SVM classifier was able to distinguish calcium from manganese, zinc, iron and nickel, as well as all five of these ions from water molecules, with a high degree of accuracy. Additionally, SVMs trained on the automatically curated set of high-resolution structures were able to successfully classify most common elemental ions in an independent validation test set. This method is readily extensible to other elemental ions and can also be used in conjunction with previous methods based on a priori expectations of the chemical environment and X-ray scattering.

  13. A Generic Modeling Process to Support Functional Fault Model Development

    NASA Technical Reports Server (NTRS)

    Maul, William A.; Hemminger, Joseph A.; Oostdyk, Rebecca; Bis, Rachael A.

    2016-01-01

    Functional fault models (FFMs) are qualitative representations of a system's failure space that are used to provide a diagnostic of the modeled system. An FFM simulates the failure effect propagation paths within a system between failure modes and observation points. These models contain a significant amount of information about the system including the design, operation and off nominal behavior. The development and verification of the models can be costly in both time and resources. In addition, models depicting similar components can be distinct, both in appearance and function, when created individually, because there are numerous ways of representing the failure space within each component. Generic application of FFMs has the advantages of software code reuse: reduction of time and resources in both development and verification, and a standard set of component models from which future system models can be generated with common appearance and diagnostic performance. This paper outlines the motivation to develop a generic modeling process for FFMs at the component level and the effort to implement that process through modeling conventions and a software tool. The implementation of this generic modeling process within a fault isolation demonstration for NASA's Advanced Ground System Maintenance (AGSM) Integrated Health Management (IHM) project is presented and the impact discussed.

  14. Fast loop modeling for protein structures

    NASA Astrophysics Data System (ADS)

    Zhang, Jiong; Nguyen, Son; Shang, Yi; Xu, Dong; Kosztin, Ioan

    2015-03-01

    X-ray crystallography is the main method for determining 3D protein structures. In many cases, however, flexible loop regions of proteins cannot be resolved by this approach. This leads to incomplete structures in the protein data bank, preventing further computational study and analysis of these proteins. For instance, all-atom molecular dynamics (MD) simulation studies of structure-function relationship require complete protein structures. To address this shortcoming, we have developed and implemented an efficient computational method for building missing protein loops. The method is database driven and uses deep learning and multi-dimensional scaling algorithms. We have implemented the method as a simple stand-alone program, which can also be used as a plugin in existing molecular modeling software, e.g., VMD. The quality and stability of the generated structures are assessed and tested via energy scoring functions and by equilibrium MD simulations. The proposed method can also be used in template-based protein structure prediction. Work supported by the National Institutes of Health [R01 GM100701]. Computer time was provided by the University of Missouri Bioinformatics Consortium.

  15. Robust parametric estimation over optimal support of fluid flow structure in multispectral image sequences

    NASA Astrophysics Data System (ADS)

    Rougon, Nicolas F.; Brossard-Pailleux, M. A.; Preteux, Francoise J.

    2000-10-01

    This article presents a methodology for analyzing the Lagrangian structure of fluid flows generated by the evolution of cloud systems in meteorological multispectral image sequences. The correlation between the orientation of cloud texture and the underlying motion field Lagrangian component allows to adopt a static strategy. Following a scale-space approach, we therefore first construct a non-local robust estimator for the locally dominant orientation field in an image. This estimator, which is derived from the image structure tensor, is relevant in both mono- and multisprectral contexts. In a second step, the Lagrangian component of the flow is estimated over some bounded image region by robustly fitting a hierarchical vector parametric model to the dominant orientation field. Here, a recurrent problem deals with adaptating the geometry of the model support to obtain unbiased estimates. To tackle this classic issue, we introduce a novel variational, semi-parametric approach which allows the joint optimization of model parameters and support. This approach is generic and, in particular, can be readily applied to motion estimation yielding robust measurement of the Eulerian structure of the flow. Finally, a structural characterization of the reflecting vector field is derived by means of classic differential geometry techniques. This methodology is applied to the analysis of temperated latitude depressions in Meteosat images.

  16. Structure and order in cobalt/platinum-type nanoalloys: from thin films to supported clusters

    NASA Astrophysics Data System (ADS)

    Andreazza, Pascal; Pierron-Bohnes, Véronique; Tournus, Florent; Andreazza-Vignolle, Caroline; Dupuis, Véronique

    2015-06-01

    Among nanoalloys, Co-Pt type (CoPt or FePt) supported nanostructures are very interesting systems due to the direct link between atom arrangement and magnetic behavior. In addition, these alloys become model systems in the field of nanoalloys, due to the diversity of atom arrangements either present in the bulk state or specific to the nanoscale (chemically ordered L10, L12, or disordered fcc structures, core-shell, five-fold structures - icosahedral or decahedral, etc.). The synergy between experimental and modeling efforts has allowed the emergence of an overview of the structural, morphological and chemical behaviors of CoPt-based supported nanoparticles in terms of phase diagrams (temperature, composition, size effect), kinetic behavior (growth, annealing, ordering), and also in terms of environment effects (substrate, capping, matrix, gas) and of magnetic properties. All aspects of this complexity are reviewed: synthesis strategies (physical deposition, cluster beam deposition and wet chemical methods), magnetic behavior (atomic magnetic moment, magnetic anisotropy energy), structural transitions (non-crystalline/crystalline structures, order/disorder, surface/interface segregation), etc. In this field, the investigation techniques, such as electron microscopy and X-ray scattering or absorption techniques, are generally used at their ultimate limit due the small size of the studied objects. Finally, several aspects of the annealing process, which is a key phenomenon to achieve the chemical order, have been discussed in both thermodynamic and kinetic points of view (size effect, critical temperature, annealing time, twinning, coalescence, etc.).

  17. Automated web service composition supporting conditional branch structures

    NASA Astrophysics Data System (ADS)

    Wang, Pengwei; Ding, Zhijun; Jiang, Changjun; Zhou, Mengchu

    2014-01-01

    The creation of value-added services by automatic composition of existing ones is gaining a significant momentum as the potential silver bullet in service-oriented architecture. However, service composition faces two aspects of difficulties. First, users' needs present such characteristics as diversity, uncertainty and personalisation; second, the existing services run in a real-world environment that is highly complex and dynamically changing. These difficulties may cause the emergence of nondeterministic choices in the process of service composition, which has gone beyond what the existing automated service composition techniques can handle. According to most of the existing methods, the process model of composite service includes sequence constructs only. This article presents a method to introduce conditional branch structures into the process model of composite service when needed, in order to satisfy users' diverse and personalised needs and adapt to the dynamic changes of real-world environment. UML activity diagrams are used to represent dependencies in composite service. Two types of user preferences are considered in this article, which have been ignored by the previous work and a simple programming language style expression is adopted to describe them. Two different algorithms are presented to deal with different situations. A real-life case is provided to illustrate the proposed concepts and methods.

  18. AgBase: supporting functional modeling in agricultural organisms.

    PubMed

    McCarthy, Fiona M; Gresham, Cathy R; Buza, Teresia J; Chouvarine, Philippe; Pillai, Lakshmi R; Kumar, Ranjit; Ozkan, Seval; Wang, Hui; Manda, Prashanti; Arick, Tony; Bridges, Susan M; Burgess, Shane C

    2011-01-01

    AgBase (http://www.agbase.msstate.edu/) provides resources to facilitate modeling of functional genomics data and structural and functional annotation of agriculturally important animal, plant, microbe and parasite genomes. The website is redesigned to improve accessibility and ease of use, including improved search capabilities. Expanded capabilities include new dedicated pages for horse, cat, dog, cotton, rice and soybean. We currently provide 590 240 Gene Ontology (GO) annotations to 105 454 gene products in 64 different species, including GO annotations linked to transcripts represented on agricultural microarrays. For many of these arrays, this provides the only functional annotation available. GO annotations are available for download and we provide comprehensive, species-specific GO annotation files for 18 different organisms. The tools available at AgBase have been expanded and several existing tools improved based upon user feedback. One of seven new tools available at AgBase, GOModeler, supports hypothesis testing from functional genomics data. We host several associated databases and provide genome browsers for three agricultural pathogens. Moreover, we provide comprehensive training resources (including worked examples and tutorials) via links to Educational Resources at the AgBase website. PMID:21075795

  19. AgBase: supporting functional modeling in agricultural organisms

    PubMed Central

    McCarthy, Fiona M.; Gresham, Cathy R.; Buza, Teresia J.; Chouvarine, Philippe; Pillai, Lakshmi R.; Kumar, Ranjit; Ozkan, Seval; Wang, Hui; Manda, Prashanti; Arick, Tony; Bridges, Susan M.; Burgess, Shane C.

    2011-01-01

    AgBase (http://www.agbase.msstate.edu/) provides resources to facilitate modeling of functional genomics data and structural and functional annotation of agriculturally important animal, plant, microbe and parasite genomes. The website is redesigned to improve accessibility and ease of use, including improved search capabilities. Expanded capabilities include new dedicated pages for horse, cat, dog, cotton, rice and soybean. We currently provide 590 240 Gene Ontology (GO) annotations to 105 454 gene products in 64 different species, including GO annotations linked to transcripts represented on agricultural microarrays. For many of these arrays, this provides the only functional annotation available. GO annotations are available for download and we provide comprehensive, species-specific GO annotation files for 18 different organisms. The tools available at AgBase have been expanded and several existing tools improved based upon user feedback. One of seven new tools available at AgBase, GOModeler, supports hypothesis testing from functional genomics data. We host several associated databases and provide genome browsers for three agricultural pathogens. Moreover, we provide comprehensive training resources (including worked examples and tutorials) via links to Educational Resources at the AgBase website. PMID:21075795

  20. Support for an Evolutionary Model of AGN Nuclei

    NASA Astrophysics Data System (ADS)

    Dultzin, D.

    2015-09-01

    I will present our recent results (2013-2015) on the role of the environment in the nuclear activity of interacting Galaxies, all of which support an evolutionary sequence in the nuclear activity. We studied close galactic pairs of similar mass in the local Universe. We analyzed 385 spectra of S S, E E, and E S pairs, and try to disentangle the role of morphology on induced activity . We compare with our own sample of bona fide isolated galaxies containing a statistically significant number of all morphological types. Our main results are in conflict with the simplest version of the so called Unified Model (UM), and suggest that high accretion rates are essential to form the Broad Line Region in active galaxies. We also investigated the structure of the dusty torus surrounding Syfert 1 and 2 nuclei, both in pairs and isolated. The results also lead to a disagreement with the UM. Finally, we present our results on the Nuclear Activity in the context of the evolution of Compact Groups of galaxies over the past 3 Gyrs. Our analysis is based on the largest multiwavelength compact group sample to-date, and the results are also in conflict with an orientation obscuration effect alone.

  1. Test of a Mediation Model of Perceived Organizational Support

    ERIC Educational Resources Information Center

    Chen, Zhen Xiong; Aryee, Samuel; Lee, Cynthia

    2005-01-01

    This study examined the mediating influence of trust in organization (TIO) and organization-based self-esteem (OBSE) on the relationship between perceived organization support (POS) and its work outcomes. Data were obtained from employee-supervisor dyads from multiple organizations located in a major city in southern China. Structural equation…

  2. Molecular modeling of nucleic acid structure

    PubMed Central

    Galindo-Murillo, Rodrigo; Bergonzo, Christina

    2013-01-01

    This unit is the first in a series of four units covering the analysis of nucleic acid structure by molecular modeling. This unit provides an overview of computer simulation of nucleic acids. Topics include the static structure model, computational graphics and energy models, generation of an initial model, and characterization of the overall three-dimensional structure. PMID:18428873

  3. SDU 6 MODELING STUDY TO SUPPORT DESIGN DEVELOPMENT

    SciTech Connect

    Smith, F.

    2012-05-02

    In response to Technical Task Request (TTR) HLW-SSF-TTR-2012-0017 (1), SRNL performed modeling studies to evaluate alternative design features for the 32 million gallon Saltstone Disposal Unit (SDU) referred to as SDU 6. This initial modeling study was intended to assess the performance of major components of the structure that are most significant to the PA. Information provided by the modeling will support the development of a SDU 6 Preliminary Design Model and Recommendation Report to be written by SRR Closure and Waste Disposal Authority. Key inputs and assumptions for the modeling were provided to SRNL in SRR-SPT-2011-00113 (2). A table reiterates the base case and four sensitivity case studies requested in this reference. In general, as shown in Table 4, when compared to Vault 2 Case A, the Base Case SDU 6 design produced higher peak fluxes to the water table during the 10,000 year period of analysis but lower peak fluxes within a 15,000 to 20,000 time frame. SDU 6 will contain approximately ten times the inventory of a single Vault 2 and the SDU 6 footprint is comparable to that of a group of four Vault 2 disposal units. Therefore, the radionuclide flux from SDU 6 and that from a single Vault 2 are not directly comparable. A more direct comparison would be to compare the maximum dose obtained at the 100 m boundary from the seven SDU's that will replace the 64 FDC's analyzed in the 2009 PA. This analysis will be performed in the next set of calculations planned for SDU design evaluation. Aquifer transport and dose calculations were not intended to be part of this initial scoping study. However, results from this study do indicate that replacement of the FDC design with SDU would not yield significantly higher peak doses. If the thickness of the SDU 6 floor is increased, peak doses would not occur during the 10,000 year period of analysis.

  4. Energy Absorption Structure of Laser Supported Detonation Wave

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Yamaguchi, Toshikazu; Hatai, Keigo; Komurasaki, Kimiya; Arakawa, Yoshihiro

    2010-05-01

    In Repetitive Pulsed (RP) laser propulsion, when the high energy laser beam is focused in the thruster, Laser Supported Detonation (LSD) wave is generated. This LSD wave converts the laser energy to the enthalpy of the blast wave, which will then apply impulse to the wall of the thruster. Therefore, the energy absorption structure and sustaining condition of LSD wave are important to be understood, which was still not clear though some visualized experiments have been conducted by Ushio et al. before. In this paper, 2-wavelength Mach-Zehnder interferometry is brought to investigate the electron density distribution of LSD area. At the same time, the temperature of the laser induced plasma is measured by an emission spectroscopy experiment, and calculated based on the assumption of local thermal equilibrium. The results show that in LSD, the electron density has a peak (as high as 2×1024[m-3]) behind the shock wave. The irradiated laser can be entirely absorbed before reaching the position of this peak. As a result, a new peak is always generating in front of the old one and this propagating has the same velocity as that of the blast wave. In this way, high heating ratio is sustained right after the shock front. However, as the laser pulse energy becomes lower, the propagating peak cannot catch up with the blast wave anymore, which leads to a termination of the LSD wave. From this study, it is found that for sustaining the LSD wave, a sufficiently thin laser absorption layer is necessary.

  5. Health, Supportive Environments, and the Reasonable Person Model

    PubMed Central

    Kaplan, Stephen; Kaplan, Rachel

    2003-01-01

    The Reasonable Person Model is a conceptual framework that links environmental factors with human behavior. People are more reasonable, cooperative, helpful, and satisfied when the environment supports their basic informational needs. The same environmental supports are important factors in enhancing human health. We use this framework to identify the informational requirements common to various health-promoting factors that are realizable through welldesigned physical environments. Environmental attractors, support of way-finding, and facilitation of social interaction all contribute to the health-relevant themes of community, crime, and mode of transportation. In addition, the nearby natural environment, although often neglected, can serve as a remarkably effective resource. PMID:12948967

  6. Model Comparison of Bayesian Semiparametric and Parametric Structural Equation Models

    ERIC Educational Resources Information Center

    Song, Xin-Yuan; Xia, Ye-Mao; Pan, Jun-Hao; Lee, Sik-Yum

    2011-01-01

    Structural equation models have wide applications. One of the most important issues in analyzing structural equation models is model comparison. This article proposes a Bayesian model comparison statistic, namely the "L[subscript nu]"-measure for both semiparametric and parametric structural equation models. For illustration purposes, we consider…

  7. Effective Team Support: From Modeling to Software Agents

    NASA Technical Reports Server (NTRS)

    Remington, Roger W. (Technical Monitor); John, Bonnie; Sycara, Katia

    2003-01-01

    The purpose of this research contract was to perform multidisciplinary research between CMU psychologists, computer scientists and engineers and NASA researchers to design a next generation collaborative system to support a team of human experts and intelligent agents. To achieve robust performance enhancement of such a system, we had proposed to perform task and cognitive modeling to thoroughly understand the impact technology makes on the organization and on key individual personnel. Guided by cognitively-inspired requirements, we would then develop software agents that support the human team in decision making, information filtering, information distribution and integration to enhance team situational awareness. During the period covered by this final report, we made substantial progress in modeling infrastructure and task infrastructure. Work is continuing under a different contract to complete empirical data collection, cognitive modeling, and the building of software agents to support the teams task.

  8. CISNET lung models: Comparison of model assumptions and model structures

    PubMed Central

    McMahon, Pamela M.; Hazelton, William; Kimmel, Marek; Clarke, Lauren

    2012-01-01

    Sophisticated modeling techniques can be powerful tools to help us understand the effects of cancer control interventions on population trends in cancer incidence and mortality. Readers of journal articles are however rarely supplied with modeling details. Six modeling groups collaborated as part of the National Cancer Institute’s Cancer Intervention and Surveillance Modeling Network (CISNET) to investigate the contribution of US tobacco control efforts towards reducing lung cancer deaths over the period 1975 to 2000. The models included in this monograph were developed independently and use distinct, complementary approaches towards modeling the natural history of lung cancer. The models used the same data for inputs and agreed on the design of the analysis and the outcome measures. This article highlights aspects of the models that are most relevant to similarities of or differences between the results. Structured comparisons can increase the transparency of these complex models. PMID:22882887

  9. Design Approaches to Support Preservice Teachers in Scientific Modeling

    NASA Astrophysics Data System (ADS)

    Kenyon, Lisa; Davis, Elizabeth A.; Hug, Barbara

    2011-02-01

    Engaging children in scientific practices is hard for beginning teachers. One such scientific practice with which beginning teachers may have limited experience is scientific modeling. We have iteratively designed preservice teacher learning experiences and materials intended to help teachers achieve learning goals associated with scientific modeling. Our work has taken place across multiple years at three university sites, with preservice teachers focused on early childhood, elementary, and middle school teaching. Based on results from our empirical studies supporting these design decisions, we discuss design features of our modeling instruction in each iteration. Our results suggest some successes in supporting preservice teachers in engaging students in modeling practice. We propose design principles that can guide science teacher educators in incorporating modeling in teacher education.

  10. SVAT modelling in support to flood risk assessment in Bulgaria

    NASA Astrophysics Data System (ADS)

    Stoyanova, Julia S.; Georgiev, Christo G.

    2013-04-01

    This study explores the benefit that can be drawn from incorporating the diagnosis of initial soil moisture of the top vegetation/soil layer and its anomalies as parameters in support of operational weather forecasting. For that purpose, a 1D vertical numerical land surface scheme, referred to as Soil Vegetation Transfer Model (‘SVAT_bg’) has been developed to simulate the soil-vegetation-atmosphere mass and energy transfer, accounting for local soil/climate features. The model is run daily for estimating soil moisture content and on this basis, a biogeophysical index designating Soil Moisture Availability Index (SMAI) to vegetation land cover is derived. SMAI is introduced as a measure of the proportion between the energy and water balances and their anomalies at different weather/climate conditions through a 6-level threshold scheme of land surface moistening. To facilitate the use of SMAI as a diagnostic tool for operational forecasting purposes, it is generated on a daily basis and visualised by colour-coded maps, covering the main administrative regions of Bulgaria in combination with a numerical part, which indicates the required flood-producing rainfall quantities (specific for each region). In case of overmoistening conditions, the numerical part denotes the rainfall excess above the soil saturation moisture content. The utility of this approach is illustrated in two case studies of severe weather produced by deep convection and a rapid cyclogenesis developed at initial ‘dry’/‘wet’ soil moisture anomalies, respectively. The thermodynamic conditions and space-time structure of the rainfall are analysed by NWP output fields and satellite information. The study contributes to a better definition of the role of vegetation-soil moistening in flood risk forecasting within strong synoptic scale forcing regimes. The utility of the results comes also from the recognition of soil moisture as a meteorological forcing factor, which may affect both severity

  11. Modelling the structure of sludge aggregates

    PubMed Central

    Smoczyński, Lech; Ratnaweera, Harsha; Kosobucka, Marta; Smoczyński, Michał; Kalinowski, Sławomir; Kvaal, Knut

    2016-01-01

    ABSTRACT The structure of sludge is closely associated with the process of wastewater treatment. Synthetic dyestuff wastewater and sewage were coagulated using the PAX and PIX methods, and electro-coagulated on aluminium electrodes. The processes of wastewater treatment were supported with an organic polymer. The images of surface structures of the investigated sludge were obtained using scanning electron microscopy (SEM). The software image analysis permitted obtaining plots log A vs. log P, wherein A is the surface area and P is the perimeter of the object, for individual objects comprised in the structure of the sludge. The resulting database confirmed the ‘self-similarity’ of the structural objects in the studied groups of sludge, which enabled calculating their fractal dimension and proposing models for these objects. A quantitative description of the sludge aggregates permitted proposing a mechanism of the processes responsible for their formation. In the paper, also, the impact of the structure of the investigated sludge on the process of sedimentation, and dehydration of the thickened sludge after sedimentation, was discussed. PMID:26549812

  12. Modelling the structure of sludge aggregates.

    PubMed

    Smoczyński, Lech; Ratnaweera, Harsha; Kosobucka, Marta; Smoczyński, Michał; Kalinowski, Sławomir; Kvaal, Knut

    2016-01-01

    The structure of sludge is closely associated with the process of wastewater treatment. Synthetic dyestuff wastewater and sewage were coagulated using the PAX and PIX methods, and electro-coagulated on aluminium electrodes. The processes of wastewater treatment were supported with an organic polymer. The images of surface structures of the investigated sludge were obtained using scanning electron microscopy (SEM). The software image analysis permitted obtaining plots log A vs. log P, wherein A is the surface area and P is the perimeter of the object, for individual objects comprised in the structure of the sludge. The resulting database confirmed the 'self-similarity' of the structural objects in the studied groups of sludge, which enabled calculating their fractal dimension and proposing models for these objects. A quantitative description of the sludge aggregates permitted proposing a mechanism of the processes responsible for their formation. In the paper, also, the impact of the structure of the investigated sludge on the process of sedimentation, and dehydration of the thickened sludge after sedimentation, was discussed. PMID:26549812

  13. TMT telescope structure thermal model

    NASA Astrophysics Data System (ADS)

    Vogiatzis, Konstantinos; Sadjadpour, Amir; Roberts, Scott

    2014-08-01

    The thermal behavior of the Thirty Meter Telescope (TMT) Telescope Structure (STR) and the STR mounted subsystems depends on the heat load of the System, the thermal properties of component materials and the environment as well as their interactions through convection, conduction and radiation. In this paper the thermal environment is described and the latest three-dimensional Computational Solid Dynamics (CSD) model is presented. The model tracks the diurnal temperature variation of the STR and the corresponding deformations. The resulting displacements are fed into the TMT Merit Function Routine (MFR), which converts them into translations and rotations of the optical surfaces. They, in turn, are multiplied by the TMT optical sensitivity matrix that delivers the corresponding pointing error. Thus the thermal performance of the structure can be assessed for requirement compliance, thermal drift correction strategies and look-up tables can be developed and design guidance can be provided. Results for a representative diurnal cycle based on measured temperature data from the TMT site on Mauna Kea and CFD simulations are presented and conclusions are drawn.

  14. Orthotropic deflection model for corner-supported plates with segmented in-plane actuators.

    SciTech Connect

    Sumali, Hartono; Washington, Gregory N.; Massad, Jordan Elias

    2005-02-01

    The shape control of thin, flexible structures has been studied primarily for edge-supported thin plates. For applications involving reconfigurable apertures such as membrane optics and active RF surfaces, corner-supported configurations may prove more applicable. Corner-supported adaptive structures allow for parabolic geometries, greater flexibility, and larger achievable deflections when compared to edge-supported geometries under similar actuation conditions. Preliminary models have been developed for corner-supported thin plates actuated by isotropic piezoelectric actuators. However, typical piezoelectric materials are known to be orthotropic. This paper extends a previously-developed isotropic model for a corner-supported, thin, rectangular bimorph to a more general orthotropic model for a bimorph actuated by a two-dimensional array of segmented PVDF laminates. First, a model determining the deflected shape of an orthotropic laminate for a given distribution of voltages over the actuator array is derived. Second, symmetric actuation of a bimorph consisting of orthotropic material is simulated using orthogonally-oriented laminae. Finally, the results of the model are shown to agree well with layered-shell finite element simulations for simple and complex voltage distributions.

  15. Supporting Teachers in Structuring Mathematics Lessons Involving Challenging Tasks

    ERIC Educational Resources Information Center

    Sullivan, Peter; Askew, Mike; Cheeseman, Jill; Clarke, Doug; Mornane, Angela; Roche, Anne; Walker, Nadia

    2015-01-01

    The following is a report on an investigation into ways of supporting teachers in converting challenging mathematics tasks into classroom lessons and supporting students in engaging with those tasks. Groups of primary and secondary teachers, respectively, were provided with documentation of ten lessons built around challenging tasks. Teachers…

  16. Structural Analyses of the Support Trusses for the Nuclear Thermal Rocket Engines and Drop Tanks

    NASA Astrophysics Data System (ADS)

    Myers, David E.; Kosareo, Daniel N.

    2006-01-01

    Finite element structural analyses were performed on the support trusses of the Nuclear Thermal Rocket (NTR) engines and drop tanks to verify that the proper amount of mass was allocated for these components in the vehicle sizing model. The verification included a static stress analysis, a modal analysis, and a buckling analysis using the MSC/NASTRAN™ structural analysis software package. In addition, a crippling stress analysis was performed on the truss beams using a handbook equation. Two truss configurations were examined as possible candidates for the drop tanks truss while a baseline was examined for the engine support thrust structure. For the drop tanks trusses, results showed that both truss configurations produced similar results although one performed slightly better in buckling. In addition, it was shown that the mass allocated in the vehicle sizing model was adequate although the engine thrust structure may need to be modified slightly to increase its lateral natural frequency above the minimum requirement of 8 Hz that is specified in the Delta IV Payload Planners Guide.

  17. Model-Driven Engineering Support for Building C# Applications

    NASA Astrophysics Data System (ADS)

    Derezińska, Anna; Ołtarzewski, Przemysław

    Realization of Model-Driven Engineering (MDE) vision of software development requires a comprehensive and user-friendly tool support. This paper presents a UML-based approach for building trustful C# applications. UML models are refined using profiles for assigning class model elements to C# concepts and to elements of implementation project. Stereotyped elements are verified on life and during model to code transformation in order to prevent creation of an incorrect code. The Transform OCL Fragments into C# system (T.O.F.I.C.) was created as a feature of the Eclipse environment. The system extends the IBM Rational Software Architect tool.

  18. A numerical cloud model for the support of laboratory experimentation

    NASA Technical Reports Server (NTRS)

    Hagen, D. E.

    1979-01-01

    A numerical cloud model is presented which can describe the evolution of a cloud starting from moist aerosol-laden air through the diffusional growth regime. The model is designed for the direct support of cloud chamber laboratory experimentation, i.e., experiment preparation, real-time control and data analysis. In the model the thermodynamics is uncoupled from the droplet growth processes. Analytic solutions for the cloud droplet growth equations are developed which can be applied in most laboratory situations. The model is applied to a variety of representative experiments.

  19. Computer modeling for advanced life support system analysis.

    PubMed

    Drysdale, A

    1997-01-01

    This article discusses the equivalent mass approach to advanced life support system analysis, describes a computer model developed to use this approach, and presents early results from modeling the NASA JSC BioPlex. The model is built using an object oriented approach and G2, a commercially available modeling package Cost factor equivalencies are given for the Volosin scenarios. Plant data from NASA KSC and Utah State University (USU) are used, together with configuration data from the BioPlex design effort. Initial results focus on the importance of obtaining high plant productivity with a flight-like configuration. PMID:11540448

  20. A curved piezo-structure model: implications on active structural acoustic control.

    PubMed

    Henry, J K; Clark, R L

    1999-09-01

    Current research in Active Structural Acoustic Control (ASAC) relies heavily upon accurately capturing the application physics associated with the structure being controlled. The application of ASAC to aircraft interior noise requires a greater understanding of the dynamics of the curved panels which compose the skin of an aircraft fuselage. This paper presents a model of a simply supported curved panel with attached piezoelectric transducers. The model is validated by comparison to previous work. Further, experimental results for a simply supported curved panel test structure are presented in support of the model. The curvature is shown to affect substantially the dynamics of the panel, the integration of transducers, and the bandwidth required for structural acoustic control. PMID:10489701

  1. A New Look at the Big Five Factor Structure through Exploratory Structural Equation Modeling

    ERIC Educational Resources Information Center

    Marsh, Herbert W.; Ludtke, Oliver; Muthen, Bengt; Asparouhov, Tihomir; Morin, Alexandre J. S.; Trautwein, Ulrich; Nagengast, Benjamin

    2010-01-01

    NEO instruments are widely used to assess Big Five personality factors, but confirmatory factor analyses (CFAs) conducted at the item level do not support their a priori structure due, in part, to the overly restrictive CFA assumptions. We demonstrate that exploratory structural equation modeling (ESEM), an integration of CFA and exploratory…

  2. Communication competence, social support, and depression among college students: a model of facebook and face-to-face support network influence.

    PubMed

    Wright, Kevin B; Rosenberg, Jenny; Egbert, Nicole; Ploeger, Nicole A; Bernard, Daniel R; King, Shawn

    2013-01-01

    This study examined the influence of the social networking site Facebook and face-to-face support networks on depression among (N = 361) college students. The authors used the Relational Health Communication Competence Model as a framework for examining the influence of communication competence on social support network satisfaction and depression. Moreover, they examined the influence of interpersonal and social integrative motives as exogenous variables. On the basis of previous work, the authors propose and test a theoretical model using structural equation modeling. The results indicated empirical support for the model, with interpersonal motives predicting increased face-to-face and computer-mediated competence, increased social support satisfaction with face-to-face and Facebook support, and lower depression scores. The implications of the findings for theory, key limitations, and directions for future research are discussed. PMID:23030518

  3. Ostwald ripening of charged supported metal nanoparticles: Schottky model

    NASA Astrophysics Data System (ADS)

    Zhdanov, Vladimir P.

    2015-07-01

    Due to high surface area, supported metal nanoparticles are thermodynamically prone to sintering. The experimental studies of this process exhibit sometimes transient bimodal particle size distributions. Such observations may result from the support heterogeneity. Looking retrospectively, one can also find the prediction that in the case of Ostwald ripening this feature can be related to charge of metal nanoparticles. In real systems, this charge is often associated with the metal-support interaction and can be interpreted in the framework of the Schottky model. Using this model, the author shows that the charge redistribution cannot be behind bimodal particle size distributions. Moreover, the corresponding contribution to the driving force for Ostwald ripening is typically much smaller than the conventional one.

  4. OASIS: A GRAPHICAL DECISION SUPPORT SYSTEM FOR GROUNDWATER CONTAMINANT MODELING

    EPA Science Inventory

    Three new software technologies were applied to develop an efficient and easy to use decision support system far ground-water contaminant modeling. raphical interfaces create a more intuitive and effective form of communication with the computer compared to text-based interfaces....

  5. A Learner Support Model Based on Peer Tutor Selection

    ERIC Educational Resources Information Center

    van Rosmalen, P.; Sloep, P.; Kester, L.; Brouns, F.; de Croock, M.; Pannekeet, K.; Koper, R.

    2008-01-01

    The introduction of elearning often leads to an increase in the time staff spends on tutoring. To alleviate the workload of staff tutors, we developed a model for organizing and supporting learner-related interactions in elearning systems. It makes use of the knowledge and experience of peers and builds on the assumption that (lifelong) learners,…

  6. Modeling Positive Behavior Interventions and Supports for Preservice Teachers

    ERIC Educational Resources Information Center

    Hill, Doris Adams; Flores, Margaret M.

    2014-01-01

    The authors modeled programwide positive behavior interventions and supports (PBIS) principles to 26 preservice teachers during consolidated yearly extended school year (ESY) services delivered to elementary students from four school districts. While PBIS were in place for preservice teachers to implement with students, a similar system was…

  7. Educating All Learners: Refocusing the Comprehensive Support Model.

    ERIC Educational Resources Information Center

    Obiakor, Festus E., Ed.; Grant, Patrick A., Ed.; Dooley, Elizabeth A., Ed.

    This collection of papers addresses the importance of maximizing the fullest potential of all students and leaving no child behind. The 14 papers are: (1) "The Comprehensive Support Model for All Learners: Conceptualization and Meaning" (Festus E. Obiakor, Pauline Harris-Obiakor, and Ramel L. Smith); (2) "The Power of the `Self' in Education"…

  8. Modeling actions and operations to support mission preparation

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.; Ryan, D. P.; Schreckenghost, D. L.

    1994-01-01

    This paper describes two linked technology development projects to support Space Shuttle ground operations personnel, both during mission preparation analysis and related analyses in missions. The Space Propulsion Robust Analysis Tool (SPRAT) will provide intelligent support and automation for mission analysis setup, interpretation, reporting and documentation. SPRAT models the actions taken by flight support personnel during mission preparation and uses this model to generate an action plan. CONFIG will provide intelligent automation for procedure analyses and failure impact analyses, by simulating the interactions between operations and systems with embedded failures. CONFIG models the actions taken by crew during space vehicle malfunctions and simulates how the planned action sequences in procedures affect a device model. Jointly the SPRAT and CONFIG projects provide an opportunity to investigate how the nature of a task affects the representation of actions, and to determine a more general action representation supporting a broad range of tasks. This paper describes the problems in representing actions for mission preparation and their relation to planning and scheduling.

  9. Supporting Teachers, Strengthening Families: A Model Child Abuse Prevention Approach

    ERIC Educational Resources Information Center

    Olson, Maril

    2007-01-01

    This article talks about a model child abuse prevention approach called, "Supporting Teachers, Strengthening Families." It is NAEYC's professional development initiative to help early childhood educators play leading roles in preventing child abuse and neglect through family strengthening efforts. It focuses on six strategies that high-quality…

  10. MSW Time to Tumor Model and Supporting Documentation

    EPA Science Inventory

    The multistage Weibull (MSW) time-to-tumor model and related documentation were developed principally (but not exclusively) for conducting time-to-tumor analyses to support risk assessments under the IRIS program. These programs and related docum...

  11. Designing Electronic Performance Support Systems: Models and Instructional Strategies Employed

    ERIC Educational Resources Information Center

    Nekvinda, Christopher D.

    2011-01-01

    The purpose of this qualitative study was to determine whether instructional designers and performance technologists utilize instructional design models when designing and developing electronic performance support systems (EPSS). The study also explored if these same designers were utilizing instructional strategies within their EPSS to support…

  12. Training of Existing Workers: Issues, Incentives and Models. Support Document

    ERIC Educational Resources Information Center

    Mawer, Giselle; Jackson, Elaine

    2005-01-01

    This document was produced by the authors based on their research for the report, "Training of Existing Workers: Issues, Incentives and Models," (ED495138) and is an added resource for further information. This support document is divided into the following sections: (1) The Retail Industry--A Snapshot; (2) Case Studies--Hardware, Retail Industry…

  13. Seismic analysis of offshore wind turbines on bottom-fixed support structures.

    PubMed

    Alati, Natale; Failla, Giuseppe; Arena, Felice

    2015-02-28

    This study investigates the seismic response of a horizontal axis wind turbine on two bottom-fixed support structures for transitional water depths (30-60 m), a tripod and a jacket, both resting on pile foundations. Fully coupled, nonlinear time-domain simulations on full system models are carried out under combined wind-wave-earthquake loadings, for different load cases, considering fixed and flexible foundation models. It is shown that earthquake loading may cause a significant increase of stress resultant demands, even for moderate peak ground accelerations, and that fully coupled nonlinear time-domain simulations on full system models are essential to capture relevant information on the moment demand in the rotor blades, which cannot be predicted by analyses on simplified models allowed by existing standards. A comparison with some typical design load cases substantiates the need for an accurate seismic assessment in sites at risk from earthquakes. PMID:25583865

  14. Interactive Modelling of Molecular Structures

    NASA Astrophysics Data System (ADS)

    Rustad, J. R.; Kreylos, O.; Hamann, B.

    2004-12-01

    The "Nanotech Construction Kit" (NCK) [1] is a new project aimed at improving the understanding of molecular structures at a nanometer-scale level by visualization and interactive manipulation. Our very first prototype is a virtual-reality program allowing the construction of silica and carbon structures from scratch by assembling them one atom at a time. In silica crystals or glasses, the basic building block is an SiO4 unit, with the four oxygen atoms arranged around the central silicon atom in the shape of a regular tetrahedron. Two silicate units can connect to each other by their silicon atoms covalently bonding to one shared oxygen atom. Geometrically, this means that two tetrahedra can link at their vertices. Our program is based on geometric representations and uses simple force fields to simulate the interaction of building blocks, such as forming/breaking of bonds and repulsion. Together with stereoscopic visualization and direct manipulation of building blocks using wands or data gloves, this enables users to create realistic and complex molecular models in short amounts of time. The NCK can either be used as a standalone tool, to analyze or experiment with molecular structures, or it can be used in combination with "traditional" molecular dynamics (MD) simulations. In a first step, the NCK can create initial configurations for subsequent MD simulation. In a more evolved setup, the NCK can serve as a visual front-end for an ongoing MD simulation, visualizing changes in simulation state in real time. Additionally, the NCK can be used to change simulation state on-the-fly, to experiment with different simulation conditions, or force certain events, e.g., the forming of a bond, and observe the simulation's reaction. [1] http://graphics.cs.ucdavis.edu/~okreylos/ResDev/NanoTech

  15. Investigating Models for Preservice Teachers' Use of Technology to Support Student-Centered Learning

    ERIC Educational Resources Information Center

    Chen, Rong-Ji

    2010-01-01

    The study addressed two limitations of previous research on factors related to teachers' integration of technology in their teaching. It attempted to test a structural equation model (SEM) of the relationships among a set of variables influencing preservice teachers' use of technology specifically to support student-centered learning. A review of…

  16. Online model-based diagnosis to support autonomous operation of an advanced life support system

    NASA Technical Reports Server (NTRS)

    Biswas, Gautam; Manders, Eric-Jan; Ramirez, John; Mahadevan, Nagabhusan; Abdelwahed, Sherif

    2004-01-01

    This article describes methods for online model-based diagnosis of subsystems of the advanced life support system (ALS). The diagnosis methodology is tailored to detect, isolate, and identify faults in components of the system quickly so that fault-adaptive control techniques can be applied to maintain system operation without interruption. We describe the components of our hybrid modeling scheme and the diagnosis methodology, and then demonstrate the effectiveness of this methodology by building a detailed model of the reverse osmosis (RO) system of the water recovery system (WRS) of the ALS. This model is validated with real data collected from an experimental testbed at NASA JSC. A number of diagnosis experiments run on simulated faulty data are presented and the results are discussed.

  17. Online model-based diagnosis to support autonomous operation of an advanced life support system.

    PubMed

    Biswas, Gautam; Manders, Eric-Jan; Ramirez, John; Mahadevan, Nagabhusan; Abdelwahed, Sherif

    2004-01-01

    This article describes methods for online model-based diagnosis of subsystems of the advanced life support system (ALS). The diagnosis methodology is tailored to detect, isolate, and identify faults in components of the system quickly so that fault-adaptive control techniques can be applied to maintain system operation without interruption. We describe the components of our hybrid modeling scheme and the diagnosis methodology, and then demonstrate the effectiveness of this methodology by building a detailed model of the reverse osmosis (RO) system of the water recovery system (WRS) of the ALS. This model is validated with real data collected from an experimental testbed at NASA JSC. A number of diagnosis experiments run on simulated faulty data are presented and the results are discussed. PMID:15880907

  18. The Structure of Social Exchange in Self-Help Support Groups: Development of a Measure

    PubMed Central

    Brown, Louis D.; Tang, Xiaohui; Hollman, Ruth L.

    2014-01-01

    Self-help support groups are indigenous community resources designed to help people manage a variety of personal challenges, from alcohol abuse to xeroderma pigmentosum. The social exchanges that occur during group meetings are central to understanding how people benefit from participation. This paper examines the different types of social exchange behaviors that occur during meetings, using two studies to develop empirically distinct scales that reliably measure theoretically important types of exchange. Resource theory informed the initial measurement development efforts. Exploratory factor analyses from the first study led to revisions in the factor structure of the social exchange scales. The revised measure captured the exchange of emotional support, experiential information, humor, unwanted behaviors, and exchanges outside meetings. Confirmatory factor analyses from a follow-up study with a different sample of self-help support groups provided good model fit, suggesting the revised structure accurately represented the data. Further, the scales demonstrated good convergent and discriminant validity with related constructs. Future research can use the scales to identify aspects of social exchange that are most important in improving health outcomes among self-help support group participants. Groups can use the scales in practice to celebrate strengths and address weaknesses in their social exchange dynamics. PMID:24398622

  19. The structure of social exchange in self-help support groups: development of a measure.

    PubMed

    Brown, Louis D; Tang, Xiaohui; Hollman, Ruth L

    2014-03-01

    Self-help support groups are indigenous community resources designed to help people manage a variety of personal challenges, from alcohol abuse to xeroderma pigmentosum. The social exchanges that occur during group meetings are central to understanding how people benefit from participation. This paper examines the different types of social exchange behaviors that occur during meetings, using two studies to develop empirically distinct scales that reliably measure theoretically important types of exchange. Resource theory informed the initial measurement development efforts. Exploratory factor analyses from the first study led to revisions in the factor structure of the social exchange scales. The revised measure captured the exchange of emotional support, experiential information, humor, unwanted behaviors, and exchanges outside meetings. Confirmatory factor analyses from a follow-up study with a different sample of self-help support groups provided good model fit, suggesting the revised structure accurately represented the data. Further, the scales demonstrated good convergent and discriminant validity with related constructs. Future research can use the scales to identify aspects of social exchange that are most important in improving health outcomes among self-help support group participants. Groups can use the scales in practice to celebrate strengths and address weaknesses in their social exchange dynamics. PMID:24398622

  20. Supporting Universal Prevention Programs: A Two-Phased Coaching Model

    PubMed Central

    Becker, Kimberly D.; Darney, Dana; Domitrovich, Celene; Keperling, Jennifer Pitchford; Ialongo, Nicholas S.

    2013-01-01

    Schools are adopting evidence-based programs designed to enhance students’ emotional and behavioral competencies at increasing rates (Hemmeter, Snyder, & Artman, 2011). At the same time, teachers express the need for increased support surrounding implementation of these evidence-based programs (Carter & Van Norman, 2010). Ongoing professional development in the form of coaching may enhance teacher skills and implementation (Noell et al., 2005; Stormont, Reinke, Newcomer, Darney, & Lewis, 2012). There exists a need for a coaching model that can be applied to a variety of teacher skill levels and one that guides coach decision-making about how best to support teachers. This article provides a detailed account of a two-phased coaching model with empirical support developed and tested with coaches and teachers in urban schools (Becker, Bradshaw, Domitrovich, & Ialongo, 2013). In the initial universal coaching phase, all teachers receive the same coaching elements regardless of their skill level. Then, in the tailored coaching phase, coaching varies according to the strengths and needs of each teacher. Specifically, more intensive coaching strategies are used only with teachers who need additional coaching supports whereas other teachers receive just enough support to consolidate and maintain their strong implementation. Examples of how coaches used the two-phased coaching model when working with teachers who were implementing two universal prevention programs (i.e., the PATHS® curriculum and PAX Good Behavior Game [PAX GBG]) provide illustrations of the application of this model. The potential reach of this coaching model extends to other school-based programs as well as other settings in which coaches partner with interventionists to implement evidence-based programs. PMID:23660973

  1. Structural model uncertainty in stochastic simulation

    SciTech Connect

    McKay, M.D.; Morrison, J.D.

    1997-09-01

    Prediction uncertainty in stochastic simulation models can be described by a hierarchy of components: stochastic variability at the lowest level, input and parameter uncertainty at a higher level, and structural model uncertainty at the top. It is argued that a usual paradigm for analysis of input uncertainty is not suitable for application to structural model uncertainty. An approach more likely to produce an acceptable methodology for analyzing structural model uncertainty is one that uses characteristics specific to the particular family of models.

  2. Influence of backup bearings and support structure dynamics on the behavior of rotors with active supports

    NASA Technical Reports Server (NTRS)

    Flowers, George T.

    1994-01-01

    Progress over the past year includes the following: A simplified rotor model with a flexible shaft and backup bearings has been developed. A simple rotor model which includes a flexible disk and bearings with clearance has been developed and the dynamics of the model investigated. A rotor model based upon the T-501 engine has been developed which includes backup bearing effects. Parallel simulation runs are being conducted using an ANSYS based finite element model of the T-501. The magnetic bearing test rig is currently floating and dynamics/control tests are being conducted. A paper has been written that documents the work using the T-501 engine model. Work has continued with the simplified model. The finite element model is currently being modified to include the effects of foundation dynamics. A literature search for material on foil bearings has been conducted. A finite element model is being developed for a magnetic bearing in series with a foil backup bearing.

  3. Influence of backup bearings and support structure dynamics on the behavior of rotors with active supports

    NASA Technical Reports Server (NTRS)

    Flowers, George T.

    1994-01-01

    Substantial progress has been made toward the goals of this research effort in the past six months. A simplified rotor model with a flexible shaft and backup bearings has been developed. The model is based upon the work of Ishii and Kirk. Parameter studies of the behavior of this model are currently being conducted. A simple rotor model which includes a flexible disk and bearings with clearance has been developed and the dynamics of the model investigated. The study consists of simulation work coupled with experimental verification. The work is documented in the attached paper. A rotor model based upon the T-501 engine has been developed which includes backup bearing effects. The dynamics of this model are currently being studied with the objective of verifying the conclusions obtained from the simpler models. Parallel simulation runs are being conducted using an ANSYS based finite element model of the T-501.

  4. Educational Support for Low-Performing Students in Mathematics: The Three-Tier Support Model in Finnish Lower Secondary Schools

    ERIC Educational Resources Information Center

    Ekstam, Ulrika; Linnanmäki, Karin; Aunio, Pirjo

    2015-01-01

    In 2011, there was a legislative reform regarding educational support in Finland, with a focus on early identification, differentiation and flexible arrangement of support using a multi-professional approach, the three-tier support model. The main aim of this study was to investigate what educational support practices are used with low-performing…

  5. The Effects of a Structured Academic Support Group on GPA and Self-Concept of Ability.

    ERIC Educational Resources Information Center

    Cooper, Stewart E.; Robinson, Debra A. G.

    1987-01-01

    A structured academic support group for 21 high ability but underachieving undergraduate students resulted in improved study and self management skills, peer support, improvements in student grade point averages, and improved self concept scores. (Author/DB)

  6. Influence of the supporting die structures on the fracture strength of all-ceramic materials.

    PubMed

    Yucel, Munir Tolga; Yondem, Isa; Aykent, Filiz; Eraslan, Oğuz

    2012-08-01

    This study investigated the influence of the elastic modulus of supporting dies on the fracture strengths of all-ceramic materials used in dental crowns. Four different types of supporting die materials (dentin, epoxy resin, brass, and stainless steel) (24 per group) were prepared using a milling machine to simulate a mandibular molar all-ceramic core preparation. A total number of 96 zirconia cores were fabricated using a CAD/CAM system. The specimens were divided into two groups. In the first group, cores were cemented to substructures using a dual-cure resin cement. In the second group, cores were not cemented to the supporting dies. The specimens were loaded using a universal testing machine at a crosshead speed of 0.5 mm/min until fracture occurred. Data were statistically analyzed using two-way analysis of variance and Tukey HSD tests (α = 0.05). The geometric models of cores and supporting die materials were developed using finite element method to obtain the stress distribution of the forces. Cemented groups showed statistically higher fracture strength values than non-cemented groups. While ceramic cores on stainless steel dies showed the highest fracture strength values, ceramic cores on dentin dies showed the lowest fracture strength values among the groups. The elastic modulus of the supporting die structure is a significant factor in determining the fracture resistance of all-ceramic crowns. Using supporting die structures that have a low elastic modulus may be suitable for fracture strength tests, in order to accurately reflect clinical conditions. PMID:21845404

  7. Behavior Change Support Systems: A Research Model and Agenda

    NASA Astrophysics Data System (ADS)

    Oinas-Kukkonen, Harri

    This article introduces the concept of a behavior change support system and suggests it as a key construct for research on persuasive systems design, technologies, and applications. Key concepts for behavior change support systems are defined and a research agenda for them is outlined. The article suggests that a change in complying, a behavior change, and an attitude change (C-, B- or A-Change) constitute the archetypes of a behavioral change. Change in itself is either of a forming, altering or reinforcing outcome (F-, A- or R-Outcome). This research model will become helpful in researching and designing persuasive technology.

  8. The effect of alkylating agents on model supported metal clusters

    SciTech Connect

    Erdem-Senatalar, A.; Blackmond, D.G.; Wender, I. . Dept. of Chemical and Petroleum Engineering); Oukaci, R. )

    1988-01-01

    Interactions between model supported metal clusters and alkylating agents were studied in an effort to understand a novel chemical trapping technique developed for identifying species adsorbed on catalyst surfaces. It was found that these interactions are more complex than had previously been suggested. Studies were completed using deuterium-labeled dimethyl sulfate (DMS), (CH{sub 3}){sub 2}SO{sub 4}, as a trapping agent to interact with the supported metal cluster ethylidyne tricobalt enneacarbonyl. Results showed that oxygenated products formed during the trapping reaction contained {minus}OCD{sub 3} groups from the DMS, indicating that the interaction was not a simple alkylation. 18 refs., 1 fig., 3 tabs.

  9. The Specific Analysis of Structural Equation Models

    ERIC Educational Resources Information Center

    McDonald, Roderick P.

    2004-01-01

    Conventional structural equation modeling fits a covariance structure implied by the equations of the model. This treatment of the model often gives misleading results because overall goodness of fit tests do not focus on the specific constraints implied by the model. An alternative treatment arising from Pearl's directed acyclic graph theory…

  10. Experimental research on tape spring supported space inflatable structures

    NASA Astrophysics Data System (ADS)

    Cook, Andrew J.; Walker, Scott J. I.

    2016-01-01

    This paper presents experimental research that continues the development of inflatable hybrid structures for space applications. Inflatables provide a concept with much scope for further incorporation into the structures of future spacecraft. They offer considerable savings in mass and stowed volume for spacecraft, providing possible reductions in satellite costs. Existing boom configurations make use of inflatables including solar arrays and the NGST sunshield. However these typically soft systems could be improved by incorporating tape springs as structural stiffeners along the length of the boom, creating hybrid structures. This research builds on previous experimental work undertaken at the University of Southampton looking at cantilever inflatable and hybrid booms. The focus of this research is to identify the structural performance improvement of adding tape springs to cantilever inflatable booms. This is achieved by tip deflection testing to determine the bending moment and rigidity performances of these structures allowing a comparison between the two technologies. Several hybrid booms are created and tested in various orientations to identify the optimal tape spring effectiveness. It was found that adding a pair of tape springs will increase stiffness of the hybrid structure by up to 4.9 times for an increase of 2.4 times the boom mass.

  11. Learning the Structure of Mixed Graphical Models

    PubMed Central

    Lee, Jason D.; Hastie, Trevor J.

    2014-01-01

    We consider the problem of learning the structure of a pairwise graphical model over continuous and discrete variables. We present a new pairwise model for graphical models with both continuous and discrete variables that is amenable to structure learning. In previous work, authors have considered structure learning of Gaussian graphical models and structure learning of discrete models. Our approach is a natural generalization of these two lines of work to the mixed case. The penalization scheme involves a novel symmetric use of the group-lasso norm and follows naturally from a particular parametrization of the model. Supplementary materials for this paper are available online. PMID:26085782

  12. Anchoring Schoolwide Positive Behavior Support in Structural School Reform

    ERIC Educational Resources Information Center

    Sailor, Wayne; Zuna, Nina; Choi, Jeong-Hoon; Thomas, Jamie; McCart, Amy; Roger, Blair

    2006-01-01

    Schoolwide positive behavior support (SWPBS) exemplifies a longitudinal research program originating in the fields of special education and school psychology that has produced an extensive national database encompassing an evidence-based set of practices applicable to general education as well as special education students including those with…

  13. Social Support Structures and African-American Marriages.

    ERIC Educational Resources Information Center

    Curry-El, Judith A.; And Others

    An issue currently facing the African-American community is the incidence of divorce, which is presently at a higher rate than that of other groups. This study focused on the supportive networks of African-American couples utilizing a network analysis approach to examine the relationship between the networks, and marital satisfaction among the…

  14. Modeling the effect of piezoceramic hysteresis in structural vibration control

    NASA Astrophysics Data System (ADS)

    Ozer, Mehmet B.; Royston, Thomas J.

    2001-08-01

    Dielectric hysteresis in piezoceramic transducers can degrade their performance in structural vibration control applications. Different hysteresis models have been applied to piezoelectric transducers, including those based on Preisach, Jiles-Atherton and Ishlinskii concepts. Relationships between these and other models, new experimental identification schemes and multi-term describing function representations of some of them are reviewed. Then, system equations that incorporate the hysteretic behavior are formulated for two pedagogical smart structural systems: a passively shunted / actively driven PZT wafer on (1) a simply supported thin plate and (2) a simply supported thin beam. The effect of PZT hysteresis on optimized passive and hybrid vibration control strategies is evaluated.

  15. Data and Models Needed to Support Civil Aviation

    NASA Astrophysics Data System (ADS)

    Onsager, Terrance; Biesecker, D. A.; Berger, Thomas; Rutledge, Robert

    2016-07-01

    The effective utilization of existing data and models is an important element in advancing the goals of the COSPAR/ILWS space weather roadmap. This is recommended to be done through innovative approaches to data utilization, including data driving, data assimilation, and ensemble modeling. This presentation will focus on observations and models needed to support space weather services for civil aviation and commercial space transportation. The service needs for aviation will be discussed, and an overview will be given of some of the existing data and models that can provide these services. Efforts underway to define the requirements for real-time data and to assess current modeling capabilities will be described. Recommendations will be offered for internationally coordinated activities that could identify priorities and further the roadmap goals.

  16. Interpreting linear support vector machine models with heat map molecule coloring

    PubMed Central

    2011-01-01

    Background Model-based virtual screening plays an important role in the early drug discovery stage. The outcomes of high-throughput screenings are a valuable source for machine learning algorithms to infer such models. Besides a strong performance, the interpretability of a machine learning model is a desired property to guide the optimization of a compound in later drug discovery stages. Linear support vector machines showed to have a convincing performance on large-scale data sets. The goal of this study is to present a heat map molecule coloring technique to interpret linear support vector machine models. Based on the weights of a linear model, the visualization approach colors each atom and bond of a compound according to its importance for activity. Results We evaluated our approach on a toxicity data set, a chromosome aberration data set, and the maximum unbiased validation data sets. The experiments show that our method sensibly visualizes structure-property and structure-activity relationships of a linear support vector machine model. The coloring of ligands in the binding pocket of several crystal structures of a maximum unbiased validation data set target indicates that our approach assists to determine the correct ligand orientation in the binding pocket. Additionally, the heat map coloring enables the identification of substructures important for the binding of an inhibitor. Conclusions In combination with heat map coloring, linear support vector machine models can help to guide the modification of a compound in later stages of drug discovery. Particularly substructures identified as important by our method might be a starting point for optimization of a lead compound. The heat map coloring should be considered as complementary to structure based modeling approaches. As such, it helps to get a better understanding of the binding mode of an inhibitor. PMID:21439031

  17. Modeling Insurgent Network Structure and Dynamics

    NASA Astrophysics Data System (ADS)

    Gabbay, Michael; Thirkill-Mackelprang, Ashley

    2010-03-01

    We present a methodology for mapping insurgent network structure based on their public rhetoric. Indicators of cooperative links between insurgent groups at both the leadership and rank-and-file levels are used, such as joint policy statements or joint operations claims. In addition, a targeting policy measure is constructed on the basis of insurgent targeting claims. Network diagrams which integrate these measures of insurgent cooperation and ideology are generated for different periods of the Iraqi and Afghan insurgencies. The network diagrams exhibit meaningful changes which track the evolution of the strategic environment faced by insurgent groups. Correlations between targeting policy and network structure indicate that insurgent targeting claims are aimed at establishing a group identity among the spectrum of rank-and-file insurgency supporters. A dynamical systems model of insurgent alliance formation and factionalism is presented which evolves the relationship between insurgent group dyads as a function of their ideological differences and their current relationships. The ability of the model to qualitatively and quantitatively capture insurgent network dynamics observed in the data is discussed.

  18. Characterization of Effect of Support Structures in Laser Additive Manufacturing of Stainless Steel

    NASA Astrophysics Data System (ADS)

    Järvinen, Jukka-Pekka; Matilainen, Ville; Li, Xiaoyun; Piili, Heidi; Salminen, Antti; Mäkelä, Ismo; Nyrhilä, Olli

    Laser additive manufacturing (LAM) of stainless steel is a layer wisetechnology for fabricating 3D parts from metal powder via selectively melting powder with laser beam. Support structures play a significant role in LAM process as they help to remove heat away from the process and on the other hand hold the work piece in its place. A successful design of support structures can help to achievea building process fast and inexpensive with high quality. Aimof this study was to characterize the usability of two types of support structures: web and tube supports. Purpose of this studywas also to analyze how suitable they are in two industrial application cases: case for dental application and case for jewelry application. It was concluded that the removability of web supports was much better than tube supports. It was noticed that support structures are an important part of LAM process and they strongly affect the manufacturability and the end quality of the part.

  19. Model-supported exploitation of synthetic aperture radar images

    NASA Astrophysics Data System (ADS)

    Chellappa, Rama; Kuttikkad, Shyam; Meth, Reuven; Burlina, Philippe; Shekhar, Chandra S.

    1996-02-01

    We address the application of model-supported exploitation techniques to synthetic aperture radar (SAR) imagery. The emphasis is on monitoring SAR imagery using wide area 2D and/or 3D site models along with contextual information. We consider here the following tasks useful in monitoring: (a) site model construction using segmentation and labeling techniques, (b) target detection, (c) target classification and indexing, and (d) SAR image-site model registration. The 2-D wide area site models used here for SAR image exploitation differ from typical site models developed for RADIUS applications, in that they do not model specific facilities, but constitute wide area site models of cultural features such as urban clutter areas, roads, clearings, fields, etc. These models may be derived directly from existing site models, possibly constructed from electro-optical (EO) observations. When such models are not available, a set of segmentation and labeling techniques described here can be used for the construction of 2D site models. The use of models can potentially yield critical information which can disambiguate target signatures in SAR images. We address registration of SAR and EO images to a common site model. Specific derivations are given for the case of registration within the RCDE platform. We suggest a constant false alarm rate (CFAR) detection scheme and a topographic primal sketch (TPS) based classification scheme for monitoring target occurrences in SAR images. The TPS of an observed target is matched against candidate targets TPSs synthesized for the preferred target orientation, inferred from context (e.g. road or parking lot targets). Experimental results on real and synthetic SAR images are provided.

  20. Crankshaft supporting and lubricating structure for multicylinder internal combustion engines

    SciTech Connect

    Anno, N.

    1987-04-14

    This patent describes a crankshaft supporting and lubricating device in a multicylinder internal combustion engine having bearing caps secured to journal walls of a cylinder block rotatably supporting a crankshaft between the bearing caps and the journal walls with a bridge interconnecting the bearing caps. The improvement described here comprises: the bearing caps and the bridge having branch oil passages defined therein for supplying lubricating oil to bearings of the crankshaft; the branch oil passages being deviated to one side from a cylinder axis passing through the center of the crankshaft; the bridge having a main gallery defined therein in communication with the branch oil passages and also deviated to the one side; and the bridge and one of the bearing caps having an oil passage defined therein on the one side and providing communication between the main gallery and a pressurized oil source.

  1. Engine Structures Modeling Software System (ESMOSS)

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Engine Structures Modeling Software System (ESMOSS) is the development of a specialized software system for the construction of geometric descriptive and discrete analytical models of engine parts, components, and substructures which can be transferred to finite element analysis programs such as NASTRAN. The NASA Lewis Engine Structures Program is concerned with the development of technology for the rational structural design and analysis of advanced gas turbine engines with emphasis on advanced structural analysis, structural dynamics, structural aspects of aeroelasticity, and life prediction. Fundamental and common to all of these developments is the need for geometric and analytical model descriptions at various engine assembly levels which are generated using ESMOSS.

  2. Model-based decision support in diabetes care.

    PubMed

    Salzsieder, E; Vogt, L; Kohnert, K-D; Heinke, P; Augstein, P

    2011-05-01

    The model-based Karlsburg Diabetes Management System (KADIS®) has been developed as a patient-focused decision-support tool to provide evidence-based advice for physicians in their daily efforts to optimize metabolic control in diabetes care of their patients on an individualized basis. For this purpose, KADIS® was established in terms of a personalized, interactive in silico simulation procedure, implemented into a problem-related diabetes health care network and evaluated under different conditions by conducting open-label mono- and polycentric trials, and a case-control study, and last but not least, by application in routine diabetes outpatient care. The trial outcomes clearly show that the recommendations provided to the physicians by KADIS® lead to significant improvement of metabolic control. This model-based decision-support system provides an excellent tool to effectively guide physicians in personalized decision-making to achieve optimal metabolic control for their patients. PMID:20621384

  3. Large-scale ligand-based predictive modelling using support vector machines.

    PubMed

    Alvarsson, Jonathan; Lampa, Samuel; Schaal, Wesley; Andersson, Claes; Wikberg, Jarl E S; Spjuth, Ola

    2016-01-01

    The increasing size of datasets in drug discovery makes it challenging to build robust and accurate predictive models within a reasonable amount of time. In order to investigate the effect of dataset sizes on predictive performance and modelling time, ligand-based regression models were trained on open datasets of varying sizes of up to 1.2 million chemical structures. For modelling, two implementations of support vector machines (SVM) were used. Chemical structures were described by the signatures molecular descriptor. Results showed that for the larger datasets, the LIBLINEAR SVM implementation performed on par with the well-established libsvm with a radial basis function kernel, but with dramatically less time for model building even on modest computer resources. Using a non-linear kernel proved to be infeasible for large data sizes, even with substantial computational resources on a computer cluster. To deploy the resulting models, we extended the Bioclipse decision support framework to support models from LIBLINEAR and made our models of logD and solubility available from within Bioclipse. PMID:27516811

  4. Caring for our own: the role of institutionalized support structures in Native American nursing student success.

    PubMed

    Cech, Erin A; Metz, Anneke M; Babcock, Tracy; Smith, Jessi L

    2011-09-01

    In this project, the authors asked 19 Native American baccalaureate nursing students to discuss their experiences with a formal institutionalized student support program called "Caring for Our Own: A Reservation/University Partnership Program." The authors investigated the importance of different types of support structures within this program, as viewed by Native American nursing students. They distinguished between four institutionalized support structures: tangible, informational, emotional, and belonging. The authors found that students consider tangible support (such as stipends) to be comparatively less important than other types of support, particularly emotional and belonging support. Responses also revealed the importance of a fifth type of institutionalized support-motivational. The authors further discuss how these institutionalized support structures might lead to successful outcomes for Native American nursing students. PMID:21598863

  5. Information Model Translation to Support a Wider Science Community

    NASA Astrophysics Data System (ADS)

    Hughes, John S.; Crichton, Daniel; Ritschel, Bernd; Hardman, Sean; Joyner, Ronald

    2014-05-01

    The Planetary Data System (PDS), NASA's long-term archive for solar system exploration data, has just released PDS4, a modernization of the PDS architecture, data standards, and technical infrastructure. This next generation system positions the PDS to meet the demands of the coming decade, including big data, international cooperation, distributed nodes, and multiple ways of analysing and interpreting data. It also addresses three fundamental project goals: providing more efficient data delivery by data providers to the PDS, enabling a stable, long-term usable planetary science data archive, and enabling services for the data consumer to find, access, and use the data they require in contemporary data formats. The PDS4 information architecture is used to describe all PDS data using a common model. Captured in an ontology modeling tool it supports a hierarchy of data dictionaries built to the ISO/IEC 11179 standard and is designed to increase flexibility, enable complex searches at the product level, and to promote interoperability that facilitates data sharing both nationally and internationally. A PDS4 information architecture design requirement stipulates that the content of the information model must be translatable to external data definition languages such as XML Schema, XMI/XML, and RDF/XML. To support the semantic Web standards we are now in the process of mapping the contents into RDF/XML to support SPARQL capable databases. We are also building a terminological ontology to support virtually unified data retrieval and access. This paper will provide an overview of the PDS4 information architecture focusing on its domain information model and how the translation and mapping are being accomplished.

  6. Neighborhood Supported Model Level Fuzzy Aggregation for Moving Object Segmentation.

    PubMed

    Chiranjeevi, Pojala; Sengupta, Somnath

    2014-02-01

    We propose a new algorithm for moving object detection in the presence of challenging dynamic background conditions. We use a set of fuzzy aggregated multifeature similarity measures applied on multiple models corresponding to multimodal backgrounds. The algorithm is enriched with a neighborhood-supported model initialization strategy for faster convergence. A model level fuzzy aggregation measure driven background model maintenance ensures more robustness. Similarity functions are evaluated between the corresponding elements of the current feature vector and the model feature vectors. Concepts from Sugeno and Choquet integrals are incorporated in our algorithm to compute fuzzy similarities from the ordered similarity function values for each model. Model updating and the foreground/background classification decision is based on the set of fuzzy integrals. Our proposed algorithm is shown to outperform other multi-model background subtraction algorithms. The proposed approach completely avoids explicit offline training to initialize background model and can be initialized with moving objects also. The feature space uses a combination of intensity and statistical texture features for better object localization and robustness. Our qualitative and quantitative studies illustrate the mitigation of varieties of challenging situations by our approach. PMID:24235250

  7. Model-It: A Case Study of Learner-Centered Software Design for Supporting Model Building.

    ERIC Educational Resources Information Center

    Jackson, Shari L.; Stratford, Steven J.; Krajcik, Joseph S.; Soloway, Elliot

    Learner-centered software design (LCSD) guides the design of tasks, tools, and interfaces in order to support the unique needs of learners: growth, diversity and motivation. This paper presents a framework for LCSD and describes a case study of its application to the ScienceWare Model-It, a learner-centered tool to support scientific modeling and…

  8. A Chemical Properties Simulator to Support Integrated Environmental Modeling

    EPA Science Inventory

    Users of Integrated Environmental Modeling (IEM) systems are responsible for defining individual chemicals and their properties, a process that is time-consuming at best and overwhelming at worst, especially for new chemicals with new structures. A software tool is needed to allo...

  9. A Chemical Properties Simulator to Support Integrated Environmental Modeling (proceeding)

    EPA Science Inventory

    Users of Integrated Environmental Modeling (IEM) systems are responsible for defining individual chemicals and their properties, a process that is time-consuming at best and overwhelming at worst, especially for new chemicals with new structures. A software tool is needed to allo...

  10. Content Consumption and Hierarchical Structures of Web-Supported Courses

    ERIC Educational Resources Information Center

    Hershkovitz, Arnon; Hardof-Jaffe, Sharon; Nachmias, Rafi

    2014-01-01

    This study presents an empirical investigation of the relationship between the hierarchical structure of content delivered to students within a Learning Management System (LMS) and its actual consumption. To this end, campus-wide data relating to 1,203 courses were collected from the LMS' servers and were subsequently analyzed using data…

  11. A Confidant Support and Problem Solving Model of Divorced Fathers’ Parenting

    PubMed Central

    DeGarmo, David S.; Forgatch, Marion S.

    2011-01-01

    This study tested a hypothesized social interaction learning (SIL) model of confidant support and paternal parenting. The latent growth curve analysis employed 230 recently divorced fathers, of which 177 enrolled support confidants, to test confidant support as a predictor of problem solving outcomes and problem solving outcomes as predictors of change in fathers’ parenting. Fathers’ parenting was hypothesized to predict growth in child behavior. Observational measures of support behaviors and problem solving outcomes were obtained from structured discussions of personal and parenting issues faced by the fathers. Findings replicated and extended prior cross-sectional studies with divorced mothers and their confidants. Confidant support predicted better problem solving outcomes, problem solving predicted more effective parenting, and parenting in turn predicted growth in children’s reduced total problem behavior T scores over 18 months. Supporting a homophily perspective, fathers’ antisociality was associated with confidant antisociality but only fathers’ antisociality influenced the support process model. Intervention implications are discussed regarding SIL parent training and social support. PMID:21541814

  12. AgRISTARS. Supporting research: Algorithms for scene modelling

    NASA Technical Reports Server (NTRS)

    Rassbach, M. E. (Principal Investigator)

    1982-01-01

    The requirements for a comprehensive analysis of LANDSAT or other visual data scenes are defined. The development of a general model of a scene and a computer algorithm for finding the particular model for a given scene is discussed. The modelling system includes a boundary analysis subsystem, which detects all the boundaries and lines in the image and builds a boundary graph; a continuous variation analysis subsystem, which finds gradual variations not well approximated by a boundary structure; and a miscellaneous features analysis, which includes texture, line parallelism, etc. The noise reduction capabilities of this method and its use in image rectification and registration are discussed.

  13. Influence of Back-Up Bearings and Support Structure Dynamics on the Behavior of Rotors With Active Supports

    NASA Technical Reports Server (NTRS)

    Flowers, George T.

    1996-01-01

    This report presents a synopsis of the research work. Specific accomplishments are itemized below: (1) Experimental facilities have been developed. This includes a magnetic bearing test rig and an auxiliary bearing test rig. In addition, components have been designed, constructed, and tested for use with a rotordynamics test rig located at NASA Lewis Research Center. (2) A study of the rotordynamics of an auxiliary bearing supported T-501 engine model was performed. (3) An experimental/simulation study of auxiliary bearing rotordynamics has been performed. (4) A rotordynamical model for a magnetic bearing supported rotor system, including auxiliary bearing effects has been developed and simulation studies performed.(5) A finite element model for a foil bearing has been developed and studies of a rotor supported by foil bearings have been performed. (6) Two students affiliated with this project have graduated with M.S. degrees.

  14. Relationships between structure and activity of carbon as a multifunctional support for electrocatalysts.

    PubMed

    Stevanović, Sanja I; Panić, Vladimir V; Dekanski, Aleksandar B; Tripković, Amalija V; Jovanović, Vladislava M

    2012-07-14

    We report on new insights into the relationships between structure and activity of glassy carbon (GC), as a model material for electrocatalyst support, during its anodization in acid solution. Our investigation strongly confirms the role of CFGs in promotion of Pt activity by the "spill-over" effect related to CO(ads) for methanol electrooxidation (MEO) on a carbon-supported Pt catalyst. Combined analysis of voltammetric and impedance behaviour as well as changes in GC surface morphology induced by intensification of anodizing conditions reveal an intrinsic influence of the carbon functionalization and the structure of a graphene oxide (GO) layer on the electrical and electrocatalytic properties of activated GC. Although GO continuously grows during anodization, it structurally changes from being a graphite inter-layer within graphite ribbons toward a continuous GO surface layer that deteriorates the native structure of GC. As a consequence of the increased distance between GO-spaced graphite layers, the GC conductivity decreases until the case of profound GO exfoliation under drastic anodizing conditions. This exposes the native, yet abundantly functionalized, GC texture. While GC capacitance continuously increases with intensification of anodizing conditions, the surface nano-roughness and GO resistance reach the highest values at modest anodizing conditions, and then decrease upon drastic anodization due to the onset of GO exfoliation. We found for the first time that the activity of a GC-supported Pt catalyst in MEO, as one of the promising half-reactions in polymer electrolyte fuel cells, strictly follows the changes in GC nano-roughness and GO-induced GC resistance. The highest GC/Pt MEO activity is reached when optimal distance between graphite layers and optimal degree of GC functionalization bring the highest amount of CFGs into intimate contact with the Pt surface. This confirms the promoting role of CFGs in MEO catalysis. PMID:22648036

  15. Attachment-based family therapy for depressed and suicidal adolescents: theory, clinical model and empirical support.

    PubMed

    Ewing, E Stephanie Krauthamer; Diamond, Guy; Levy, Suzanne

    2015-01-01

    Attachment-Based Family Therapy (ABFT) is a manualized family-based intervention designed for working with depressed adolescents, including those at risk for suicide, and their families. It is an empirically informed and supported treatment. ABFT has its theoretical underpinnings in attachment theory and clinical roots in structural family therapy and emotion focused therapies. ABFT relies on a transactional model that aims to transform the quality of adolescent-parent attachment, as a means of providing the adolescent with a more secure relationship that can support them during challenging times generally, and the crises related to suicidal thinking and behavior, specifically. This article reviews: (1) the theoretical foundations of ABFT (attachment theory, models of emotional development); (2) the ABFT clinical model, including training and supervision factors; and (3) empirical support. PMID:25778674

  16. Predicting the auto-ignition temperatures of organic compounds from molecular structure using support vector machine.

    PubMed

    Pan, Yong; Jiang, Juncheng; Wang, Rui; Cao, Hongyin; Cui, Yi

    2009-05-30

    A quantitative structure-property relationship (QSPR) study is suggested for the prediction of auto-ignition temperatures (AIT) of organic compounds. Various kinds of molecular descriptors were calculated to represent the molecular structures of compounds, such as topological, charge, and geometric descriptors. The variable selection method of genetic algorithm (GA) was employed to select optimal subset of descriptors that have significant contribution to the overall AIT property from the large pool of calculated descriptors. The novel modeling method of support vector machine (SVM) was then employed to model the possible quantitative relationship existed between these selected descriptors and AIT property. The resulted model showed high prediction ability with the average absolute error being 28.88 degrees C, and the root mean square error being 36.86 for the prediction set, which are within the range of the experimental error of AIT measurements. The proposed method can be successfully used to predict the auto-ignition temperatures of organic compounds with only nine pre-selected theoretical descriptors which can be calculated directly from molecular structure alone. PMID:18952371

  17. A flexible and efficient multi-model framework in support of water management

    NASA Astrophysics Data System (ADS)

    Wolfs, Vincent; Tran Quoc, Quan; Willems, Patrick

    2016-05-01

    Flexible, fast and accurate water quantity models are essential tools in support of water management. Adjustable levels of model detail and the ability to handle varying spatial and temporal resolutions are requisite model characteristics to ensure that such models can be employed efficiently in various applications. This paper uses a newly developed flexible modelling framework that aims to generate such models. The framework incorporates several approaches to model catchment hydrology, rivers and floodplains, and the urban drainage system by lumping processes on different levels. To illustrate this framework, a case study of integrated hydrological-hydraulic modelling is elaborated for the Grote Nete catchment in Belgium. Three conceptual rainfall-runoff models (NAM, PDM and VHM) were implemented in a generalized model structure, allowing flexibility in the spatial resolution by means of an innovative disaggregation/aggregation procedure. They were linked to conceptual hydraulic models of the rivers in the catchment, which were developed by means of an advanced model structure identification and calibration procedure. The conceptual models manage to emulate the simulation results of a detailed full hydrodynamic model accurately. The models configured using the approaches of this framework are well-suited for many applications in water management due to their very short calculation time, interfacing possibilities and adjustable level of detail.

  18. Outer planet probe engineering model structural tests

    NASA Technical Reports Server (NTRS)

    Smittkamp, J. A.; Gustin, W. H.; Griffin, M. W.

    1977-01-01

    A series of proof of concept structural tests was performed on an engineering model of the Outer Planets Atmospheric Entry Probe. The tests consisted of pyrotechnic shock, dynamic and static loadings. The tests partially verified the structural concept.

  19. Coherent structures and modeling: Some background comments

    NASA Technical Reports Server (NTRS)

    Kline, S. J.

    1987-01-01

    Coherent structures are discussed as a sequence of events (identifiable motions) in the flow which convert significant amounts of mechanical energies of the mean flow stream, into turbulent fluctuations. The use of structure information in modeling is also discussed.

  20. e-infrastructure components to support the earth system modeling community in Europe

    NASA Astrophysics Data System (ADS)

    Kindermann, Stephan

    2010-05-01

    A stepwise integration of existing expertise, distributed information resources and services of the modeling community is inevitable. A growing user community calls for consistent access to existing resources like model documentation, (post-)processing tools as well as climate model data. Whereas substantial effort is invested to establish world wide climate model data handling infrastructures (e.g. the CMIP5/ESG data federation), e-infrastructural support to integrate information from the existing modeling groups, data centers as well as computing centers is missing. From a technical viewpoint, in this talk we discuss the selection and development of e-infrastructural components for the European IS-ENES project. These components should facilitate consistent access to the european CMIP5/AR5 data and service providers in addition to providing a consistent view to diverse information and tools provided by the european modeling community. The components discussed include: portal technology, information exchange protocols to collect highly structured as well as less structured descriptions (metadata) in the portal, semantic web technology to support searching based on a conceptual model. A prototype of a semantic search interface for the IS-ENES portal is hereby described in more detail. It is based on a first conceptual model taking into account the information model developed in the Metafor FP7 project as well as specific IS-ENES needs. Metafor will provide the metadata foundation of the future CMIP5 data federation and thus provides a highly structured conceptual model for the model and model output related part of the IS-ENES infrastructure. This has to be related to less structured information sources describing associated dokumentation, tools, expertise, etc. in the community.

  1. Two Models of Magnetic Support for Photoevaporated Molecular Clouds

    SciTech Connect

    Ryutov, D; Kane, J; Mizuta, A; Pound, M; Remington, B

    2004-05-05

    The thermal pressure inside molecular clouds is insufficient for maintaining the pressure balance at an ablation front at the cloud surface illuminated by nearby UV stars. Most probably, the required stiffness is provided by the magnetic pressure. After surveying existing models of this type, we concentrate on two of them: the model of a quasi-homogeneous magnetic field and the recently proposed model of a ''magnetostatic turbulence''. We discuss observational consequences of the two models, in particular, the structure and the strength of the magnetic field inside the cloud and in the ionized outflow. We comment on the possible role of reconnection events and their observational signatures. We mention laboratory experiments where the most significant features of the models can be tested.

  2. CSMOS GROUNDWATER MODELING SOFTWARE (CENTER FOR SUBSURFACE MODELING SUPPORT, SUBSURFACE PROTECTION AND REMEDIATION DIVISION, NRMRL)

    EPA Science Inventory

    The Center for Subsurface Modeling Support (CSMoS), which is part of NRMRL's Subsurface Protection and Remediation Division, distributes various public domain groundwater and vadose zone models. A short decription of each model is available. You can obtain both models and manuals...

  3. Data publication with the structural biology data grid supports live analysis

    DOE PAGESBeta

    Meyer, Peter A.; Socias, Stephanie; Key, Jason; Ransey, Elizabeth; Tjon, Emily C.; Buschiazzo, Alejandro; Lei, Ming; Botka, Chris; Withrow, James; Neau, David; et al

    2016-03-07

    Access to experimental X-ray diffraction image data is fundamental for validation and reproduction of macromolecular models and indispensable for development of structural biology processing methods. Here, we established a diffraction data publication and dissemination system, Structural Biology Data Grid (SBDG; data.sbgrid.org), to preserve primary experimental data sets that support scientific publications. Data sets are accessible to researchers through a community driven data grid, which facilitates global data access. Our analysis of a pilot collection of crystallographic data sets demonstrates that the information archived by SBDG is sufficient to reprocess data to statistics that meet or exceed the quality of themore » original published structures. SBDG has extended its services to the entire community and is used to develop support for other types of biomedical data sets. In conclusion, it is anticipated that access to the experimental data sets will enhance the paradigm shift in the community towards a much more dynamic body of continuously improving data analysis.« less

  4. Torque sensor having a spoked sensor element support structure

    NASA Technical Reports Server (NTRS)

    Lurie, Boris J. (Inventor); Schier, J. Alan (Inventor)

    1990-01-01

    Piezoelectric sensor devices are attached across pairs of circularly arranged spokes arrayed on the periphery of an annular ring. The sensor devices each include a preloaded steel ball mounting arrangement for mounting a piezoelectric sensor element. A first circular interface plate on one side of the sensor structure attaches to alternate one of the spokes, and a circular interface plate on the opposite side of the same diameter as the first interface plate attaches to the remaining spokes.

  5. Bayesian Data-Model Fit Assessment for Structural Equation Modeling

    ERIC Educational Resources Information Center

    Levy, Roy

    2011-01-01

    Bayesian approaches to modeling are receiving an increasing amount of attention in the areas of model construction and estimation in factor analysis, structural equation modeling (SEM), and related latent variable models. However, model diagnostics and model criticism remain relatively understudied aspects of Bayesian SEM. This article describes…

  6. The Structure and Quality of Social Network Support among Mental Health Consumers of Clubhouse Programs

    ERIC Educational Resources Information Center

    Pernice-Duca, Francesca M.

    2008-01-01

    This study explored the structure and quality of social network support among a group of adult consumers of community-based mental health programs known as "clubhouses". The structure and quality of social network support was also examined by diagnosis, specifically between consumers living with and without schizophrenia. The study involved a…

  7. Heart and lung support interaction--modeling and simulation.

    PubMed

    Darowski, M

    2000-01-01

    Mechanical support of the lungs used to preserve life or during any kind of surgery may have an adverse effect on the cardiovascular system. Usually, positive pressure in alveoli diminishes lung perfusion, venous return and cardiac output. Positive pressure during the respiratory cycle is transfered into the thoracic space. The aim of this study was to assess how synchronization of the respirator with spontaneous breathing influences the distribution of pressure and ventilation in nonhomogeneous lungs and how it should influence hemodynamics. For this purpose a multicompartmental model of respiratory system mechanics was used in the electrical analog of a respirator-lung circuit, which enabled us to simultaneously simulate ventilatory support and spontaneous breathing. Mechanical properties of the respiratory system were modeled by lumped parameters: resistances and capacitances of constant values, independent of lung volume or inspiratory flow changes. A multicompartmental model of the respiratory system enabled us to simulate lung pathology characterized by non-homogeneity of the mechanical properties of the different parts of the lungs. The results of simulations presented in the paper enable us to conclude that lung volume increase, independent of the respirator-patient breathing synchronization, may be modeled as the increase in pulmonary vascular resistance and alveolar pressure increase, dependent on respirator-patient breathing synchronization, may be averaged by esophageous balloon measurements which show intrathoracic pressure changes. PMID:11014677

  8. Mimetic butterflies support Wallace's model of sexual dimorphism.

    PubMed

    Kunte, Krushnamegh

    2008-07-22

    Theoretical and empirical observations generally support Darwin's view that sexual dimorphism evolves due to sexual selection on, and deviation in, exaggerated male traits. Wallace presented a radical alternative, which is largely untested, that sexual dimorphism results from naturally selected deviation in protective female coloration. This leads to the prediction that deviation in female rather than male phenotype causes sexual dimorphism. Here I test Wallace's model of sexual dimorphism by tracing the evolutionary history of Batesian mimicry-an example of naturally selected protective coloration-on a molecular phylogeny of Papilio butterflies. I show that sexual dimorphism in Papilio is significantly correlated with both female-limited Batesian mimicry, where females are mimetic and males are non-mimetic, and with the deviation of female wing colour patterns from the ancestral patterns conserved in males. Thus, Wallace's model largely explains sexual dimorphism in Papilio. This finding, along with indirect support from recent studies on birds and lizards, suggests that Wallace's model may be more widely useful in explaining sexual dimorphism. These results also highlight the contribution of naturally selected female traits in driving phenotypic divergence between species, instead of merely facilitating the divergence in male sexual traits as described by Darwin's model. PMID:18426753

  9. Operations and support cost modeling using Markov chains

    NASA Technical Reports Server (NTRS)

    Unal, Resit

    1989-01-01

    Systems for future missions will be selected with life cycle costs (LCC) as a primary evaluation criterion. This reflects the current realization that only systems which are considered affordable will be built in the future due to the national budget constaints. Such an environment calls for innovative cost modeling techniques which address all of the phases a space system goes through during its life cycle, namely: design and development, fabrication, operations and support; and retirement. A significant portion of the LCC for reusable systems are generated during the operations and support phase (OS). Typically, OS costs can account for 60 to 80 percent of the total LCC. Clearly, OS costs are wholly determined or at least strongly influenced by decisions made during the design and development phases of the project. As a result OS costs need to be considered and estimated early in the conceptual phase. To be effective, an OS cost estimating model needs to account for actual instead of ideal processes by associating cost elements with probabilities. One approach that may be suitable for OS cost modeling is the use of the Markov Chain Process. Markov chains are an important method of probabilistic analysis for operations research analysts but they are rarely used for life cycle cost analysis. This research effort evaluates the use of Markov Chains in LCC analysis by developing OS cost model for a hypothetical reusable space transportation vehicle (HSTV) and suggests further uses of the Markov Chain process as a design-aid tool.

  10. Using support vector machines to improve elemental ion identification in macromolecular crystal structures

    DOE PAGESBeta

    Morshed, Nader; Echols, Nathaniel; Adams, Paul D.

    2015-04-25

    In the process of macromolecular model building, crystallographers must examine electron density for isolated atoms and differentiate sites containing structured solvent molecules from those containing elemental ions. This task requires specific knowledge of metal-binding chemistry and scattering properties and is prone to error. A method has previously been described to identify ions based on manually chosen criteria for a number of elements. Here, the use of support vector machines (SVMs) to automatically classify isolated atoms as either solvent or one of various ions is described. Two data sets of protein crystal structures, one containing manually curated structures deposited with anomalousmore » diffraction data and another with automatically filtered, high-resolution structures, were constructed. On the manually curated data set, an SVM classifier was able to distinguish calcium from manganese, zinc, iron and nickel, as well as all five of these ions from water molecules, with a high degree of accuracy. Additionally, SVMs trained on the automatically curated set of high-resolution structures were able to successfully classify most common elemental ions in an independent validation test set. This method is readily extensible to other elemental ions and can also be used in conjunction with previous methods based on a priori expectations of the chemical environment and X-ray scattering.« less

  11. Using support vector machines to improve elemental ion identification in macromolecular crystal structures

    SciTech Connect

    Morshed, Nader; Echols, Nathaniel; Adams, Paul D.

    2015-04-25

    In the process of macromolecular model building, crystallographers must examine electron density for isolated atoms and differentiate sites containing structured solvent molecules from those containing elemental ions. This task requires specific knowledge of metal-binding chemistry and scattering properties and is prone to error. A method has previously been described to identify ions based on manually chosen criteria for a number of elements. Here, the use of support vector machines (SVMs) to automatically classify isolated atoms as either solvent or one of various ions is described. Two data sets of protein crystal structures, one containing manually curated structures deposited with anomalous diffraction data and another with automatically filtered, high-resolution structures, were constructed. On the manually curated data set, an SVM classifier was able to distinguish calcium from manganese, zinc, iron and nickel, as well as all five of these ions from water molecules, with a high degree of accuracy. Additionally, SVMs trained on the automatically curated set of high-resolution structures were able to successfully classify most common elemental ions in an independent validation test set. This method is readily extensible to other elemental ions and can also be used in conjunction with previous methods based on a priori expectations of the chemical environment and X-ray scattering.

  12. Using support vector machines to improve elemental ion identification in macromolecular crystal structures

    PubMed Central

    Morshed, Nader; Echols, Nathaniel; Adams, Paul D.

    2015-01-01

    In the process of macromolecular model building, crystallographers must examine electron density for isolated atoms and differentiate sites containing structured solvent molecules from those containing elemental ions. This task requires specific knowledge of metal-binding chemistry and scattering properties and is prone to error. A method has previously been described to identify ions based on manually chosen criteria for a number of elements. Here, the use of support vector machines (SVMs) to automatically classify isolated atoms as either solvent or one of various ions is described. Two data sets of protein crystal structures, one containing manually curated structures deposited with anomalous diffraction data and another with automatically filtered, high-resolution structures, were constructed. On the manually curated data set, an SVM classifier was able to distinguish calcium from manganese, zinc, iron and nickel, as well as all five of these ions from water molecules, with a high degree of accuracy. Additionally, SVMs trained on the automatically curated set of high-resolution structures were able to successfully classify most common elemental ions in an independent validation test set. This method is readily extensible to other elemental ions and can also be used in conjunction with previous methods based on a priori expectations of the chemical environment and X-ray scattering. PMID:25945580

  13. Bridging groundwater models and decision support with a Bayesian network

    USGS Publications Warehouse

    Fienen, Michael N.; Masterson, John P.; Plant, Nathaniel G.; Gutierrez, Benjamin T.; Thieler, E. Robert

    2013-01-01

    Resource managers need to make decisions to plan for future environmental conditions, particularly sea level rise, in the face of substantial uncertainty. Many interacting processes factor in to the decisions they face. Advances in process models and the quantification of uncertainty have made models a valuable tool for this purpose. Long-simulation runtimes and, often, numerical instability make linking process models impractical in many cases. A method for emulating the important connections between model input and forecasts, while propagating uncertainty, has the potential to provide a bridge between complicated numerical process models and the efficiency and stability needed for decision making. We explore this using a Bayesian network (BN) to emulate a groundwater flow model. We expand on previous approaches to validating a BN by calculating forecasting skill using cross validation of a groundwater model of Assateague Island in Virginia and Maryland, USA. This BN emulation was shown to capture the important groundwater-flow characteristics and uncertainty of the groundwater system because of its connection to island morphology and sea level. Forecast power metrics associated with the validation of multiple alternative BN designs guided the selection of an optimal level of BN complexity. Assateague island is an ideal test case for exploring a forecasting tool based on current conditions because the unique hydrogeomorphological variability of the island includes a range of settings indicative of past, current, and future conditions. The resulting BN is a valuable tool for exploring the response of groundwater conditions to sea level rise in decision support.

  14. Intrinsic bioremediation modeling to support Superfund site closure

    SciTech Connect

    Bedard, A.H.; Day, M.J.; Johnson, R.H.; Ritter, K.J.; Stancel, S.G.; Thomson, J.A.M.

    1997-09-01

    Closure of the groundwater component of a major Superfund site has been accomplished by a combination of source control, engineered in-situ bioremediation, and subsequent long-term intrinsic bioremediation. Engineered bioremediation outside the source control area resulted in very significant contaminant mass removal. This allowed intrinsic bioremediation to be considered as a passive remedial management method of achieving cleanup objectives after active remediation needed. Modeling demonstrated that intrinsic bioremediation would achieve cleanup objectives (for this site, Federal drinking water standards) within ten years of shutdown of the active bioremediation system. Modeling showed that residual electron acceptors and nutrients distributed in the aquifer during engineered bioremediation greatly enhance the intrinsic bioremediation process. The results of the modeling effort led to the active system being shut down a year ahead of schedule, allowing the project to move into a low-maintenance intrinsic bioremediation and long-term monitoring phase. The modeling demonstration coupled Visual MODFLOW{copyright} and BioTrans{copyright} to simulate groundwater flow, solute transport, and oxygen-limited, multi-species biodegradation. Regional flow evaluation, detailed model sensitivity analyses, and subarea modeling were employed to provide support to model predictions. Predictions will be tested by subsequent progress and compliance monitoring. Site closure began in early 1996.

  15. The European ALMA Regional Centre: a model of user support

    NASA Astrophysics Data System (ADS)

    Andreani, P.; Stoehr, F.; Zwaan, M.; Hatziminaoglou, E.; Biggs, A.; Diaz-Trigo, M.; Humphreys, E.; Petry, D.; Randall, S.; Stanke, T.; van Kampen, E.; Bárta, M.; Brand, J.; Gueth, F.; Hogerheijde, M.; Bertoldi, F.; Muxlow, T.; Richards, A.; Vlemmings, W.

    2014-08-01

    The ALMA Regional Centres (ARCs) form the interface between the ALMA observatory and the user community from the proposal preparation stage to the delivery of data and their subsequent analysis. The ARCs provide critical services to both the ALMA operations in Chile and to the user community. These services were split by the ALMA project into core and additional services. The core services are financed by the ALMA operations budget and are critical to the successful operation of ALMA. They are contractual obligations and must be delivered to the ALMA project. The additional services are not funded by the ALMA project and are not contractual obligations, but are critical to achieve ALMA full scientific potential. A distributed network of ARC nodes (with ESO being the central ARC) has been set up throughout Europe at the following seven locations: Bologna, Bonn-Cologne, Grenoble, Leiden, Manchester, Ondrejov, Onsala. These ARC nodes are working together with the central node at ESO and provide both core and additional services to the ALMA user community. This paper presents the European ARC, and how it operates in Europe to support the ALMA community. This model, although complex in nature, is turning into a very successful one, providing a service to the scientific community that has been so far highly appreciated. The ARC could become a reference support model in an age where very large collaborations are required to build large facilities, and support is needed for geographically and culturally diverse communities.

  16. A scheme for supporting distributed data structures on multicomputers

    NASA Technical Reports Server (NTRS)

    Hiranandani, Seema; Saltz, Joel; Berryman, Harry; Mehrotra, Piyush

    1990-01-01

    A data migration mechanism is proposed that allows an explicit and controlled mapping of data to memory. While read or write copies of each data element can be assigned to any processor's memory, longer term storage of each data element is assigned to a specific location in the memory of a particular processor. The proposed integration of a data migration scheme with a compiler is able to eliminate the migration of unneeded data that can occur in multiprocessor paging or caching. The overhead of adjudicating multiple concurrent writes to the same page or cache line is also eliminated. Data is presented that suggests that the scheme may be a pratical method for efficiently supporting data migration.

  17. Modeling, Analysis, and Optimization Issues for Large Space Structures

    NASA Technical Reports Server (NTRS)

    Pinson, L. D. (Compiler); Amos, A. K. (Compiler); Venkayya, V. B. (Compiler)

    1983-01-01

    Topics concerning the modeling, analysis, and optimization of large space structures are discussed including structure-control interaction, structural and structural dynamics modeling, thermal analysis, testing, and design.

  18. Challenges in structural approaches to cell modeling.

    PubMed

    Im, Wonpil; Liang, Jie; Olson, Arthur; Zhou, Huan-Xiang; Vajda, Sandor; Vakser, Ilya A

    2016-07-31

    Computational modeling is essential for structural characterization of biomolecular mechanisms across the broad spectrum of scales. Adequate understanding of biomolecular mechanisms inherently involves our ability to model them. Structural modeling of individual biomolecules and their interactions has been rapidly progressing. However, in terms of the broader picture, the focus is shifting toward larger systems, up to the level of a cell. Such modeling involves a more dynamic and realistic representation of the interactomes in vivo, in a crowded cellular environment, as well as membranes and membrane proteins, and other cellular components. Structural modeling of a cell complements computational approaches to cellular mechanisms based on differential equations, graph models, and other techniques to model biological networks, imaging data, etc. Structural modeling along with other computational and experimental approaches will provide a fundamental understanding of life at the molecular level and lead to important applications to biology and medicine. A cross section of diverse approaches presented in this review illustrates the developing shift from the structural modeling of individual molecules to that of cell biology. Studies in several related areas are covered: biological networks; automated construction of three-dimensional cell models using experimental data; modeling of protein complexes; prediction of non-specific and transient protein interactions; thermodynamic and kinetic effects of crowding; cellular membrane modeling; and modeling of chromosomes. The review presents an expert opinion on the current state-of-the-art in these various aspects of structural modeling in cellular biology, and the prospects of future developments in this emerging field. PMID:27255863

  19. Multi-wavelength Raman spectroscopy study of supported vanadia catalysts: Structure identification and quantification

    SciTech Connect

    Wu, Zili

    2014-10-20

    Revealing the structure of supported metal oxide catalysts is a prerequisite for establishing the structure - catalysis relationship. Among a variety of characterization techniques, multi-wavelength Raman spectroscopy, combining resonance Raman and non-resonance Raman with different excitation wavelengths, has recently emerged as a particularly powerful tool in not only identifying but also quantifying the structure of supported metal oxide clusters. In our review, we make use of two supported vanadia systems, VOx/SiO2 and VOx/CeO2, as examples to showcase how one can employ this technique to investigate the heterogeneous structure of active oxide clusters and to understand the complex interaction between the oxide clusters and the support. Moreover, the qualitative and quantitative structural information gained from the multi-wavelength Raman spectroscopy can be utilized to provide fundamental insights for designing more efficient supported metal oxide catalysts.

  20. Multi-wavelength Raman spectroscopy study of supported vanadia catalysts: Structure identification and quantification

    DOE PAGESBeta

    Wu, Zili

    2014-10-20

    Revealing the structure of supported metal oxide catalysts is a prerequisite for establishing the structure - catalysis relationship. Among a variety of characterization techniques, multi-wavelength Raman spectroscopy, combining resonance Raman and non-resonance Raman with different excitation wavelengths, has recently emerged as a particularly powerful tool in not only identifying but also quantifying the structure of supported metal oxide clusters. In our review, we make use of two supported vanadia systems, VOx/SiO2 and VOx/CeO2, as examples to showcase how one can employ this technique to investigate the heterogeneous structure of active oxide clusters and to understand the complex interaction between themore » oxide clusters and the support. Moreover, the qualitative and quantitative structural information gained from the multi-wavelength Raman spectroscopy can be utilized to provide fundamental insights for designing more efficient supported metal oxide catalysts.« less

  1. Structural safety assessment under the low temperature of KSTAR superconducting magnet-supporting post

    NASA Astrophysics Data System (ADS)

    Her, N. I.; Sa, J. W.; Cho, S.; Do, C. J.; Choi, C. H.; Kim, B. C.; Im, K. H.; Kyum, M.; Kim, W. C.; Kim, G. H.; Yoo, B. J.; Oh, Y. K.; Kim, D. L.; Kwon, M.; Lee, G. S.; Kstar Team

    2001-01-01

    A magnet-supporting post installed between the lower TF coil cooled by 4.5 K supercritical helium and the cryostat base is one of the most important components of the superconducting magnet-supporting structure for KSTAR Tokamak. This structure should be flexible to absorb thermal shrink of the magnet and should also be rigid to support the magnet weight and the plasma disruption load. The post was designed with stainless steel (SS) 316 LN and carbon fiber reinforced plastic (CFRP) that has low thermal conductivity and high structural strength at low temperature. In order to verify the fabricability and the structural safety, a whole scale prototype of the KSTAR magnet-supporting post was manufactured and tested. Both static and compressive cyclic load tests under the maximum plasma vertical disruption load and the magnet dead weight were performed. The test results showed that the magnet-supporting post of KSTAR Tokamak was fabricable and structurally rigid.

  2. A genetic algorithm for first principles global structure optimization of supported nano structures

    SciTech Connect

    Vilhelmsen, Lasse B.; Hammer, Bjørk

    2014-07-28

    We present a newly developed publicly available genetic algorithm (GA) for global structure optimisation within atomic scale modeling. The GA is focused on optimizations using first principles calculations, but it works equally well with empirical potentials. The implementation is described and benchmarked through a detailed statistical analysis employing averages across many independent runs of the GA. This analysis focuses on the practical use of GA’s with a description of optimal parameters to use. New results for the adsorption of M{sub 8} clusters (M = Ru, Rh, Pd, Ag, Pt, Au) on the stoichiometric rutile TiO{sub 2}(110) surface are presented showing the power of automated structure prediction and highlighting the diversity of metal cluster geometries at the atomic scale.

  3. Land Surface Emission Modeling to Support Physical Precipitation Retrievals

    NASA Technical Reports Server (NTRS)

    Peters-Lidard, Christina D.; Harrison, Kenneth; Kumar, Sujay; Ferraro, Ralph; Skofronick-Jackson, Gail

    2010-01-01

    Land surface modeling and data assimilation can provide dynamic land surface state variables necessary to support physical precipitation retrieval algorithms over land. It is well-known that surface emission, particularly over the range of frequencies to be included in the Global Precipitation Measurement Mission (GPM), is sensitive to land surface states, including soil properties, vegetation type and greenness, soil moisture, surface temperature, and snow cover, density, and grain size. In order to investigate the robustness of both the land surface model states and the microwave emissivity and forward radiative transfer models, we have undertaken a multi-site investigation as part of the NASA Precipitation Measurement Missions (PMM) Land Surface Characterization. Working Group.

  4. The biobehavioral family model: testing social support as an additional exogenous variable.

    PubMed

    Woods, Sarah B; Priest, Jacob B; Roush, Tara

    2014-12-01

    This study tests the inclusion of social support as a distinct exogenous variable in the Biobehavioral Family Model (BBFM). The BBFM is a biopsychosocial approach to health that proposes that biobehavioral reactivity (anxiety and depression) mediates the relationship between family emotional climate and disease activity. Data for this study included married, English-speaking adult participants (n = 1,321; 55% female; M age = 45.2 years) from the National Comorbidity Survey Replication, a nationally representative epidemiological study of the frequency of mental disorders in the United States. Participants reported their demographics, marital functioning, social support from friends and relatives, anxiety and depression (biobehavioral reactivity), number of chronic health conditions, and number of prescription medications. Confirmatory factor analyses supported the items used in the measures of negative marital interactions, social support, and biobehavioral reactivity, as well as the use of negative marital interactions, friends' social support, and relatives' social support as distinct factors in the model. Structural equation modeling indicated a good fit of the data to the hypothesized model (χ(2)  = 846.04, p = .000, SRMR = .039, CFI = .924, TLI = .914, RMSEA = .043). Negative marital interactions predicted biobehavioral reactivity (β = .38, p < .001), as did relatives' social support, inversely (β = -.16, p < .001). Biobehavioral reactivity predicted disease activity (β = .40, p < .001) and was demonstrated to be a significant mediator through tests of indirect effects. Findings are consistent with previous tests of the BBFM with adult samples, and suggest the important addition of family social support as a predicting factor in the model. PMID:24981970

  5. Reverse hydrogen spillover on and hydrogenation of supported metal clusters: insights from computational model studies.

    PubMed

    Vayssilov, Georgi N; Petrova, Galina P; Shor, Elena A Ivanova; Nasluzov, Vladimir A; Shor, Alexei M; St Petkov, Petko; Rösch, Notker

    2012-05-01

    "Reverse" spillover of hydrogen from hydroxyl groups of the support onto supported transition metal clusters, forming multiply hydrogenated metal species, is an essential aspect of various catalytic systems which comprise small, highly active transition metal particles on a support with a high surface area. We review and analyze the results of our computational model studies related to reverse hydrogen spillover, interpreting available structural and spectral data for the supported species and examining the relationship between metal-support and metal-hydrogen interactions. On the examples of small clusters of late transition metals, adsorbed in zeolite cavities, we showed with computational model studies that reverse spillover of hydrogen is energetically favorable for late transition metals, except for Au. This preference is crucial for the chemical reactivity of such bifunctional catalytic systems because both functions, of metal species and of acidic sites, are strongly modified, in some cases even suppressed - due to partial oxidation of the metal cluster and the conversion of protons from acidic hydroxyl groups to hydride ligands of the metal moiety. Modeling multiple hydrogen adsorption on metal clusters allowed us to quantify how (i) the support affects the adsorption capacity of the clusters and (ii) structure and oxidation state of the metal moiety changes upon adsorption. In all models of neutral systems we found that the metal atoms are partially positively charged, compensated by a negative charge of the adsorbed hydrogen ligands and of the support. In a case study we demonstrated with calculated thermodynamic parameters how to predict the average hydrogen coverage of the transition metal cluster at a given temperature and hydrogen pressure. PMID:22353996

  6. Emulation Modeling with Bayesian Networks for Efficient Decision Support

    NASA Astrophysics Data System (ADS)

    Fienen, M. N.; Masterson, J.; Plant, N. G.; Gutierrez, B. T.; Thieler, E. R.

    2012-12-01

    Bayesian decision networks (BDN) have long been used to provide decision support in systems that require explicit consideration of uncertainty; applications range from ecology to medical diagnostics and terrorism threat assessments. Until recently, however, few studies have applied BDNs to the study of groundwater systems. BDNs are particularly useful for representing real-world system variability by synthesizing a range of hydrogeologic situations within a single simulation. Because BDN output is cast in terms of probability—an output desired by decision makers—they explicitly incorporate the uncertainty of a system. BDNs can thus serve as a more efficient alternative to other uncertainty characterization methods such as computationally demanding Monte Carlo analyses and others methods restricted to linear model analyses. We present a unique application of a BDN to a groundwater modeling analysis of the hydrologic response of Assateague Island, Maryland to sea-level rise. Using both input and output variables of the modeled groundwater response to different sea-level (SLR) rise scenarios, the BDN predicts the probability of changes in the depth to fresh water, which exerts an important influence on physical and biological island evolution. Input variables included barrier-island width, maximum island elevation, and aquifer recharge. The variability of these inputs and their corresponding outputs are sampled along cross sections in a single model run to form an ensemble of input/output pairs. The BDN outputs, which are the posterior distributions of water table conditions for the sea-level rise scenarios, are evaluated through error analysis and cross-validation to assess both fit to training data and predictive power. The key benefit for using BDNs in groundwater modeling analyses is that they provide a method for distilling complex model results into predictions with associated uncertainty, which is useful to decision makers. Future efforts incorporate

  7. Spatiotemporal Organization of Spin-Coated Supported Model Membranes

    NASA Astrophysics Data System (ADS)

    Simonsen, Adam Cohen

    All cells of living organisms are separated from their surroundings and organized internally by means of flexible lipid membranes. In fact, there is consensus that the minimal requirements for self-replicating life processes include the following three features: (1) information carriers (DNA, RNA), (2) a metabolic system, and (3) encapsulation in a container structure [1]. Therefore, encapsulation can be regarded as an essential part of life itself. In nature, membranes are highly diverse interfacial structures that compartmentalize cells [2]. While prokaryotic cells only have an outer plasma membrane and a less-well-developed internal membrane structure, eukaryotic cells have a number of internal membranes associated with the organelles and the nucleus. Many of these membrane structures, including the plasma membrane, are complex layered systems, but with the basic structure of a lipid bilayer. Biomembranes contain hundreds of different lipid species in addition to embedded or peripherally associated membrane proteins and connections to scaffolds such as the cytoskeleton. In vitro, lipid bilayers are spontaneously self-organized structures formed by a large group of amphiphilic lipid molecules in aqueous suspensions. Bilayer formation is driven by the entropic properties of the hydrogen bond network in water in combination with the amphiphilic nature of the lipids. The molecular shapes of the lipid constituents play a crucial role in bilayer formation, and only lipids with approximately cylindrical shapes are able to form extended bilayers. The bilayer structure of biomembranes was discovered by Gorter and Grendel in 1925 [3] using monolayer studies of lipid extracts from red blood cells. Later, a number of conceptual models were developed to rationalize the organization of lipids and proteins in biological membranes. One of the most celebrated is the fluid-mosaic model by Singer and Nicolson (1972) [4]. According to this model, the lipid bilayer component of

  8. SSME structural dynamic model development

    NASA Technical Reports Server (NTRS)

    Foley, M. J.; Tilley, D. M.; Welch, C. T.

    1983-01-01

    A mathematical model of the Space Shuttle Main Engine (SSME) as a complete assembly, with detailed emphasis on LOX and High Fuel Turbopumps is developed. The advantages of both complete engine dynamics, and high fidelity modeling are incorporated. Development of this model, some results, and projected applications are discussed.

  9. Distributed Hydrologic Modeling Apps for Decision Support in the Cloud

    NASA Astrophysics Data System (ADS)

    Swain, N. R.; Latu, K.; Christiensen, S.; Jones, N.; Nelson, J.

    2013-12-01

    Advances in computation resources and greater availability of water resources data represent an untapped resource for addressing hydrologic uncertainties in water resources decision-making. The current practice of water authorities relies on empirical, lumped hydrologic models to estimate watershed response. These models are not capable of taking advantage of many of the spatial datasets that are now available. Physically-based, distributed hydrologic models are capable of using these data resources and providing better predictions through stochastic analysis. However, there exists a digital divide that discourages many science-minded decision makers from using distributed models. This divide can be spanned using a combination of existing web technologies. The purpose of this presentation is to present a cloud-based environment that will offer hydrologic modeling tools or 'apps' for decision support and the web technologies that have been selected to aid in its implementation. Compared to the more commonly used lumped-parameter models, distributed models, while being more intuitive, are still data intensive, computationally expensive, and difficult to modify for scenario exploration. However, web technologies such as web GIS, web services, and cloud computing have made the data more accessible, provided an inexpensive means of high-performance computing, and created an environment for developing user-friendly apps for distributed modeling. Since many water authorities are primarily interested in the scenario exploration exercises with hydrologic models, we are creating a toolkit that facilitates the development of a series of apps for manipulating existing distributed models. There are a number of hurdles that cloud-based hydrologic modeling developers face. One of these is how to work with the geospatial data inherent with this class of models in a web environment. Supporting geospatial data in a website is beyond the capabilities of standard web frameworks and it

  10. A Navigation Safety Support Model for the Strait of Istanbul

    NASA Astrophysics Data System (ADS)

    Yazici, M. Anil; Otay, Emre N.

    In this study, a real time maritime traffic support model is developed for safe navigation in the Strait of Istanbul, also known as the Bosporus. The present model simulates vessel trajectories corresponding to possible headings, using channel geometry, counter traffic, and surface currents as input. A new MATLAB code is developed for the simulation and the Marine GNC Toolbox (Fossen and Perez, 2004) is used for the vessel hydrodynamics and the auto-pilot model. After computing the trajectory tree of the vessel by forward-mapping its position distribution with respect to the initial position vector, the casualty probabilities of each trajectory are found. Within certain restrictions on vessel geometry, the proposed model predicts the safest possible intended course for the transit vessels based on the navigational parameters including position, speed, and course of the vessel. The model is tested for the Strait of Istanbul for validation. Without loss of generality, the model can be used for any narrow channel with a vessel traffic system providing the necessary input.

  11. Space Station Freedom solar dynamic modules structural modelling and analysis

    SciTech Connect

    Lawrence, C.; Morris, R.

    1991-12-01

    In support of the Space Station Freedom (SSF) Solar Dynamic Power Module effort, structural design studies were performed to investigate issues related to the design of the power module, its pointing capabilities, and the integration of the module into the SSF infrastructure. Of particular concern from a structural viewpoint are the dynamics of the power module, the impact of the power module on the Space Station dynamics and controls, and the required control effort for obtaining the specified Solar Dynamic Power Module pointing accuracy. Structural analyses were performed to determine the structural dynamics attributes of both the existing and the proposed structural dynamics module designs. The objectives of these analyses were to generate validated Solar Dynamic Power Module NASTRAN finite element models, combine Space Station and power module models into integrated system models, perform finite element modal analyses to assess the effect of the relocations of the power module center of mass, and provide modal data to controls designers for control systems design.

  12. Structural characteristic responses for finite element model updating of structures

    NASA Astrophysics Data System (ADS)

    Zhou, Linren; Wang, Lei; Ou, Jinping

    2014-04-01

    The field measurements of structures are very important to the structural finite element (FE) model updating because the errors and uncertainties of a FE model are corrected directly through closing the discrepancies between the analytical responses from FE model and the measurements from field testing of a structure. Usually, the accurate and reliable field measurements are very limited. Therefore, it is very important to make full use of the limited and valuable field measurements in structural model updating to achieve a best result with the lowest cost. In this paper, structural FE model updating is investigated in the point of view of solving a mathematical problem, and different amount and category of structural dynamic responses and static responses are considered as constraints to explore their effects on the updated results of different degree and types of structural damages. The numerical studies are carried out on a space truss. Accounting for the numerical results, some inherent phenomena and connections taking account of the updating parameters, output responses and the updated results are revealed and discussed. Some useful and practicable suggestions about using the field measurements for FE model updating are provided to achieve efficient and reliable results.

  13. Modeling snail breeding in Bioregenerative Life Support System

    NASA Astrophysics Data System (ADS)

    Kovalev, Vladimir; Tikhomirov, Alexander A.; Nickolay Manukovsky, D..

    It is known that snail meat is a high quality food that is rich in protein. Hence, heliciculture or land snail farming spreads worldwide because it is a profitable business. The possibility to use the snails of Helix pomatia in Biological Life Support System (BLSS) was studied by Japanese Researches. In that study land snails were considered to be producers of animal protein. Also, snail breeding was an important part of waste processing, because snails were capable to eat the inedible plant biomass. As opposed to the agricultural snail farming, heliciculture in BLSS should be more carefully planned. The purpose of our work was to develop a model for snail breeding in BLSS that can predict mass flow rates in and out of snail facility. There are three linked parts in the model called “Stoichiometry”, “Population” and “Mass balance”, which are used in turn. Snail population is divided into 12 age groups from oviposition to one year. In the submodel “Stoichiometry” the individual snail growth and metabolism in each of 12 age groups are described with stoichiometry equations. Reactants are written on the left side of the equations, while products are written on the right side. Stoichiometry formulas of reactants and products consist of four chemical elements: C, H, O, N. The reactants are feed and oxygen, products are carbon dioxide, metabolic water, snail meat, shell, feces, slime and eggs. If formulas of substances in the stoichiometry equations are substituted with their molar masses, then stoichiometry equations are transformed to the equations of molar mass balance. To get the real mass balance of individual snail growth and metabolism one should multiply the value of each molar mass in the equations on the scale parameter, which is the ratio between mass of monthly consumed feed and molar mass of feed. Mass of monthly consumed feed and stoichiometry coefficients of formulas of meat, shell, feces, slime and eggs should be determined experimentally

  14. Sliding weight supports for W7-X magnet system: structural aspects

    NASA Astrophysics Data System (ADS)

    Bykov, V.; Fellinger, J.; Egorov, K.; Schauer, F.; Köppen, M.; Jenzsch, H.

    2015-05-01

    The Wendelstein 7-X (W7-X) stellarator is presently under commissioning at the Max-Planck-Institut für Plasmaphysik in Greifswald. The coil system consisting of 70 superconducting coils of seven different types is supported by a massive central support structure (CSS), and thermally protected by the cryostat. The magnet system weight is borne by supports which are bolted to the cold CSS. These ten so-called cryo-legs penetrate through the cryostat wall to the warm machine base. The design of the cryo-legs incorporates glass-reinforced plastic tubes to guarantee relatively small thermal conductivity. In order to ensure free thermal shrinkage of the magnet system and to reduce stresses in the cryo-legs, sliding and rotating bearings are used as interfaces to the machine base. Tie-rods between the machine base and the warm ends of the cryo-legs prevent toroidal rotation of the magnet system, as well as any other horizontal shifts due to asymmetric loads. The assembly of the magnet system introduced some vertical imperfections in the cryo-leg positions causing considerable additional internal stresses which were not considered during the design stage. In addition, originally not planned trim coils induce unsymmetrical cyclic loads. Therefore, the previously used method to analyse one magnet system module with periodical boundary conditions is not applicable. Consequently, a model of the complete magnet system, including all five modules, was created and analysed. Fatigue analyses of the cryo-legs under the new cyclic loads, applied on top of the approximately 100 t static weight, have been performed in order to evaluate the lifetime. The paper presents the progress in structural analyses of the W7-X magnet system under the as-built conditions, loads due to the trim coil operation, and results of the weight support fatigue analysis.

  15. Environmentally Friendly Corrosion Preventative Compounds for Ground Support Structures

    NASA Technical Reports Server (NTRS)

    Montgomery Eliza L.; Calle, Luz, Marina; Curran, Jerome P.; Kolody, Mark R.

    2013-01-01

    The need to use environmentally friendly technologies throughout future space-related launch programs prompted a study aimed at replacing current petroleum and solvent-based Corrosion Preventive Compounds (CPCs) with environmentally friendly alternatives. The work in this paper focused on the identification and evaluation of environmentally friendly CPCs for use in protecting flight hardware and ground support equipment from atmospheric corrosion. CPCs are used as temporary protective coatings and must survive in the aggressive coastal marine environment that exists throughout the Kennedy Space Center, Florida. The different protection behaviors of fifteen different oily film CPCs, both common petroleum-based and newer environmentally friendly types, were evaluated on various steel and aluminum substrates. CPC and substrate systems were subjected to atmospheric testing at the Kennedy Space Center's Beachside Atmospheric Corrosion Test Site, as well as cyclic accelerated corrosion testing. Each CPC also underwent physical characterization and launch-related compatibility testing. The results for the fifteen CPC systems are presented in this paper.

  16. Environmentally friendly corrosion preventive compounds for ground support structures

    NASA Astrophysics Data System (ADS)

    Montgomery, Eliza; Curran, Jerome; Calle, Luz Marina; Kolody, Mark

    The need to use environmentally friendly technologies throughout future space-related launch programs prompted a study aimed at replacing current petroleum and solvent-based corrosion preventive compounds (CPCs) with environmentally friendly alternatives. The work in this paper focused on the identification and evaluation of environmentally friendly CPCs for use in protecting flight hardware and ground support equipment from atmospheric corrosion. CPCs are used as temporary protective coatings and must survive in the aggressive coastal marine environment that exists throughout the Kennedy Space Center, Florida. The different protection behaviors of fifteen different oily film CPCs, both common petroleum-based and newer environmentally friendly types, were evaluated on various steel and aluminum substrates. CPC and substrate systems were subjected to atmospheric testing at the Kennedy Space Center's Beachside Atmospheric Corrosion Test Site, as well as cyclic accelerated corrosion testing. Each CPC also underwent physical characterization and launch-related compatibility testing. The results for the fifteen CPC systems are presented in this paper.

  17. Structure formation in the quasispherical Szekeres model

    SciTech Connect

    Bolejko, Krzysztof

    2006-06-15

    Structure formation in the Szekeres model is investigated. Since the Szekeres model is an inhomogeneous model with no symmetries, it is possible to examine the interaction of neighboring structures and its impact on the growth of a density contrast. It has been found that the mass flow from voids to clusters enhances the growth of the density contrast. In the model presented here, the growth of the density contrast is almost 8 times faster than in the linear approach.

  18. Supporting SBML as a model exchange format in software applications.

    PubMed

    Keating, Sarah M; Le Novère, Nicolas

    2013-01-01

    This chapter describes the Systems Biology Markup Language (SBML) from its origins. It describes the rationale behind and importance of having a common language when it comes to representing models. This chapter mentions the development of SBML and outlines the structure of an SBML model. It provides a section on libSBML, a useful application programming interface (API) library for reading, writing, manipulating and validating content expressed in the SBML format. Finally the chapter also provides a description of the SBML Toolbox which provides a means of facilitating the import and export of SBML from both MATLAB and Octave ( http://www.gnu.org/software/octave/) environments. PMID:23715987

  19. Community Structure of a Mental Health Internet Support Group: Modularity in User Thread Participation

    PubMed Central

    Reynolds, Julia; Bennett, Kylie; Bennett, Anthony; Cunningham, John Alastair; Griffiths, Kathleen Margaret

    2016-01-01

    Background Little is known about the community structure of mental health Internet support groups, quantitatively. A greater understanding of the factors, which lead to user interaction, is needed to explain the design information of these services and future research concerning their utility. Objective A study was conducted to determine the characteristics of users associated with the subgroup community structure of an Internet support group for mental health issues. Methods A social network analysis of the Internet support group BlueBoard (blueboard.anu.edu.au) was performed to determine the modularity of the community using the Louvain method. Demographic characteristics age, gender, residential location, type of user (consumer, carer, or other), registration date, and posting frequency in subforums (depression, generalized anxiety, social anxiety, panic disorder, bipolar disorder, obsessive compulsive disorder, borderline personality disorder, eating disorders, carers, general (eg, “chit chat”), and suggestions box) of the BlueBoard users were assessed as potential predictors of the resulting subgroup structure. Results The analysis of modularity identified five main subgroups in the BlueBoard community. Registration date was found to be the largest contributor to the modularity outcome as observed by multinomial logistic regression. The addition of this variable to the final model containing all other factors improved its classification accuracy by 46.3%, that is, from 37.9% to 84.2%. Further investigation of this variable revealed that the most active and central users registered significantly earlier than the median registration time in each group. Conclusions The five subgroups resembled five generations of BlueBoard in distinct eras that transcended discussion about different mental health issues. This finding may be due to the activity of highly engaged and central users who communicate with many other users. Future research should seek to determine

  20. The Trauma Outcome Process Assessment Model: A Structural Equation Model Examination of Adjustment

    ERIC Educational Resources Information Center

    Borja, Susan E.; Callahan, Jennifer L.

    2009-01-01

    This investigation sought to operationalize a comprehensive theoretical model, the Trauma Outcome Process Assessment, and test it empirically with structural equation modeling. The Trauma Outcome Process Assessment reflects a robust body of research and incorporates known ecological factors (e.g., family dynamics, social support) to explain…

  1. Computational Science Research in Support of Petascale Electromagnetic Modeling

    SciTech Connect

    Lee, L.-Q.; Akcelik, V; Ge, L; Chen, S; Schussman, G; Candel, A; Li, Z; Xiao, L; Kabel, A; Uplenchwar, R; Ng, C; Ko, K; /SLAC

    2008-06-20

    Computational science research components were vital parts of the SciDAC-1 accelerator project and are continuing to play a critical role in newly-funded SciDAC-2 accelerator project, the Community Petascale Project for Accelerator Science and Simulation (ComPASS). Recent advances and achievements in the area of computational science research in support of petascale electromagnetic modeling for accelerator design analysis are presented, which include shape determination of superconducting RF cavities, mesh-based multilevel preconditioner in solving highly-indefinite linear systems, moving window using h- or p- refinement for time-domain short-range wakefield calculations, and improved scalable application I/O.

  2. Mass balances for a biological life support system simulation model

    NASA Technical Reports Server (NTRS)

    Volk, Tyler; Rumel, John D.

    1987-01-01

    Design decisions to aid the development of future space-based biological life support systems (BLSS) can be made with simulation models. Here the biochemical stoichiometry is developed for: (1) protein, carbohydrate, fat, fiber, and lignin production in the edible and inedible parts of plants; (2) food consumption and production of organic solids in urine, feces, and wash water by the humans; and (3) operation of the waste processor. Flux values for all components are derived for a steady-state system with wheat as the sole food source.

  3. Archetype based patient data modeling to support treatment of pituitary adenomas.

    PubMed

    Chalopin, Claire; Lindner, Dirk; Kropf, Stefan; Denecke, Kerstin

    2015-01-01

    The treatment of patients with pituitary adenoma requires the assessment of various patient data by the clinician. Because of their heterogeneity, they are stored in different sub-information systems, limiting a fast and easy access. The objective of this paper is to apply and test the tools provided by the openEHR Foundation to model the patient data relevant for diagnosis and treatment of the disease with the future intention to implement a centralised standard-based information platform. This platform should support the clinician in the treatment of the disease and improve the information exchange with other healthcare institutions. Some results of the domain modeling, so far obtained, are presented, and the advantages of openEHR emphasized. The free tools and the large database of existing structured and standard archetypes facilitated the modeling task. The separation of the domain modeling from the application development will support the next step of development of the information platform. PMID:26262034

  4. Linking models and data on vegetation structure

    NASA Astrophysics Data System (ADS)

    Hurtt, G. C.; Fisk, J.; Thomas, R. Q.; Dubayah, R.; Moorcroft, P. R.; Shugart, H. H.

    2010-06-01

    For more than a century, scientists have recognized the importance of vegetation structure in understanding forest dynamics. Now future satellite missions such as Deformation, Ecosystem Structure, and Dynamics of Ice (DESDynI) hold the potential to provide unprecedented global data on vegetation structure needed to reduce uncertainties in terrestrial carbon dynamics. Here, we briefly review the uses of data on vegetation structure in ecosystem models, develop and analyze theoretical models to quantify model-data requirements, and describe recent progress using a mechanistic modeling approach utilizing a formal scaling method and data on vegetation structure to improve model predictions. Generally, both limited sampling and coarse resolution averaging lead to model initialization error, which in turn is propagated in subsequent model prediction uncertainty and error. In cases with representative sampling, sufficient resolution, and linear dynamics, errors in initialization tend to compensate at larger spatial scales. However, with inadequate sampling, overly coarse resolution data or models, and nonlinear dynamics, errors in initialization lead to prediction error. A robust model-data framework will require both models and data on vegetation structure sufficient to resolve important environmental gradients and tree-level heterogeneity in forest structure globally.

  5. The European ALMA Regional Centre Network: A Geographically Distributed User Support Model

    NASA Astrophysics Data System (ADS)

    Hatziminaoglou, E.; Zwaan, M.; Andreani, P.; Barta, M.; Bertoldi, F.; Brand, J.; Gueth, F.; Hogerheijde, M.; Maercker, M.; Massardi, M.; Muehle, S.; Muxlow, Th.; Richards, A.; Schilke, P.; Tilanus, R.; Vlemmings, W.; Afonso, J.; Messias, H.

    2015-12-01

    In recent years there has been a paradigm shift from centralised to geographically distributed resources. Individual entities are no longer able to host or afford the necessary expertise in-house, and, as a consequence, society increasingly relies on widespread collaborations. Although such collaborations are now the norm for scientific projects, more technical structures providing support to a distributed scientific community without direct financial or other material benefits are scarce. The network of European ALMA Regional Centre (ARC) nodes is an example of such an internationally distributed user support network. It is an organised effort to provide the European ALMA user community with uniform expert support to enable optimal usage and scientific output of the ALMA facility. The network model for the European ARC nodes is described in terms of its organisation, communication strategies and user support.

  6. Model Specification Searches in Structural Equation Modeling Using Tabu Search.

    ERIC Educational Resources Information Center

    Marcoulides, George A.; Drezner, Zvi; Schumacker, Randall E.

    1998-01-01

    Introduces an alternative structural equation modeling (SEM) specification search approach based on the Tabu search procedure. Using data with known structure, the procedure is illustrated, and its capabilities for specification searches in SEM are demonstrated. (Author/SLD)

  7. ZERODUR: bending strength data for tensile stress loaded support structures

    NASA Astrophysics Data System (ADS)

    Bizjak, Tanja; Hartmann, Peter; Westerhoff, Thomas

    2012-03-01

    In the past ZERODUR® was mainly used for mirror and substrate applications, where mechanical loads were given by its own weight. Nowadays substrates become more sophisticated and subject to higher stresses as consequences of high operational accelerations or vibrations. The integrity of structures such as reticle and wafer stages e.g. must be guaranteed with low failure probability over their full intended life time. Their design requires statistically relevant strength data and information. The usual way determining the design strength employs statistical Weibull distributions obtained from a set of experimental data extrapolating the results to low acceptable failure probability values. However, in many cases this led to allowable stress values too low for the intended application. Moreover, the experimental basis has been found to be too small for reliable calculations. For these reasons measurement series on the strength of ZERODUR® have been performed with different surface conditions employing a standardized ring-on-ring test setup. The numbers of specimens per sample have been extended from about 20 to 100 or even much more. The results for surfaces ground with different diamond grain sizes D151, D64 and D25 as well as for etched surfaces are presented in this paper. Glass ceramics like all glassy materials exhibit some strength reduction when being exposed to loads above a tensile stress threshold over long time periods. The strength change of ZERODUR® with time will be discussed on the basis of known and newly determined stress corrosion data. The results for samples with large numbers of specimens contribute new aspects to the common practice of extrapolation to low failure probability, since they provide evidence for the existence of minimum strength values depending on the structures surface conditions. For ground surfaces the evidence for minimum strength values is quite obvious. For etched surfaces minimum values are to be expected also. However

  8. Modelling and control of a rotor supported by magnetic bearings

    NASA Technical Reports Server (NTRS)

    Gurumoorthy, R.; Pradeep, A. K.

    1994-01-01

    In this paper we develop a dynamical model of a rotor and the active magnetic bearings used to support the rotor. We use this model to develop a stable state feedback control of the magnetic bearing system. We present the development of a rigid body model of the rotor, utilizing both Rotation Matrices (Euler Angles) and Euler Parameters (Quaternions). In the latter half of the paper we develop a stable state feedback control of the actively controlled magnetic bearing to control the rotor position under inbalances. The control law developed takes into account the variation of the model with rotational speed. We show stability over the whole operating range of speeds for the magnetic bearing system. Simulation results are presented to demonstrate the closed loop system performance. We develop the model of the magnetic bearing, and present two schemes for the excitation of the poles of the actively controlled magnetic bearing. We also present a scheme for averaging multiple sensor measurements and splitting the actuation forces amongst redundant actuators.

  9. Optimized Null Model for Protein Structure Networks

    PubMed Central

    Lappe, Michael; Pržulj, Nataša

    2009-01-01

    Much attention has recently been given to the statistical significance of topological features observed in biological networks. Here, we consider residue interaction graphs (RIGs) as network representations of protein structures with residues as nodes and inter-residue interactions as edges. Degree-preserving randomized models have been widely used for this purpose in biomolecular networks. However, such a single summary statistic of a network may not be detailed enough to capture the complex topological characteristics of protein structures and their network counterparts. Here, we investigate a variety of topological properties of RIGs to find a well fitting network null model for them. The RIGs are derived from a structurally diverse protein data set at various distance cut-offs and for different groups of interacting atoms. We compare the network structure of RIGs to several random graph models. We show that 3-dimensional geometric random graphs, that model spatial relationships between objects, provide the best fit to RIGs. We investigate the relationship between the strength of the fit and various protein structural features. We show that the fit depends on protein size, structural class, and thermostability, but not on quaternary structure. We apply our model to the identification of significantly over-represented structural building blocks, i.e., network motifs, in protein structure networks. As expected, choosing geometric graphs as a null model results in the most specific identification of motifs. Our geometric random graph model may facilitate further graph-based studies of protein conformation space and have important implications for protein structure comparison and prediction. The choice of a well-fitting null model is crucial for finding structural motifs that play an important role in protein folding, stability and function. To our knowledge, this is the first study that addresses the challenge of finding an optimized null model for RIGs, by

  10. Toward an Integrated Competence-Based System Supporting Lifelong Learning and Employability: Concepts, Model, and Challenges

    NASA Astrophysics Data System (ADS)

    Miao, Yongwu; van der Klink, Marcel; Boon, Jo; Sloep, Peter; Koper, Rob

    Efficient and effective lifelong learning requires that people can make informed decisions about their continuous personal development in the different stages of their life. In this paper we state that lifelong learners need to be characterized as decision-makers. In order to improve the quality of their decisions, we propose the development of an integrated lifelong learning and employment support system, which traces learners’ competence development and provides a decision support environment. An abstract conceptual model has been developed and the main design ideas have been documented using Z notation. Moreover, we analyzed the main technical challenges for the realization of the target system: competence information fusion, decision analysis models, spatial indexing structures and browsing structures and visualization of competence-related information objects.

  11. A Tabletop Tool for Modeling Life Support Systems

    NASA Technical Reports Server (NTRS)

    Ramachandran, N.; Majumdar, A.; McDaniels, D.; Stewart, E.

    2003-01-01

    This paper describes the development plan for a comprehensive research and diagnostic tool for aspects of advanced life support systems in space-based laboratories. Specifically it aims to build a high fidelity tabletop model that can be used for the purpose of risk mitigation, failure mode analysis, contamination tracking, and testing reliability. We envision a comprehensive approach involving experimental work coupled with numerical simulation to develop this diagnostic tool. It envisions a 10% scale transparent model of a space platform such as the International Space Station that operates with water or a specific matched index of refraction liquid as the working fluid. This allows the scaling of a 10 ft x 10 ft x 10 ft room with air flow to 1 ft x 1 ft x 1 ft tabletop model with water/liquid flow. Dynamic similitude for this length scale dictates model velocities to be 67% of full-scale and thereby the time scale of the model to represent 15% of the full- scale system; meaning identical processes in the model are completed in 15% of the full- scale time. The use of an index matching fluid (fluid that matches the refractive index of cast acrylic, the model material) allows making the entire model (with complex internal geometry) transparent and hence conducive to non-intrusive optical diagnostics. So using such a system one can test environment control parameters such as core flows (axial flows), cross flows (from registers and diffusers), potential problem areas such as flow short circuits, inadequate oxygen content, build up of other gases beyond desirable levels, test mixing processes within the system at local nodes or compartments and assess the overall system performance. The system allows quantitative measurements of contaminants introduced in the system and allows testing and optimizing the tracking process and removal of contaminants. The envisaged system will be modular and hence flexible for quick configuration change and subsequent testing. The data

  12. Making Risk Models Operational for Situational Awareness and Decision Support

    SciTech Connect

    Paulson, Patrick R.; Coles, Garill A.; Shoemaker, Steven V.

    2012-06-12

    Modernization of nuclear power operations control systems, in particular the move to digital control systems, creates an opportunity to modernize existing legacy infrastructure and extend plant life. We describe here decision support tools that allow the assessment of different facets of risk and support the optimization of available resources to reduce risk as plants are upgraded and maintained. This methodology could become an integrated part of the design review process and a part of the operations management systems. The methodology can be applied to the design of new reactors such as small nuclear reactors (SMR), and be helpful in assessing the risks of different configurations of the reactors. Our tool provides a low cost evaluation of alternative configurations and provides an expanded safety analysis by considering scenarios while early in the implementation cycle where cost impacts can be minimized. The effects of failures can be modeled and thoroughly vetted to understand their potential impact on risk. The process and tools presented here allow for an integrated assessment of risk by supporting traditional defense in depth approaches while taking into consideration the insertion of new digital instrument and control systems.

  13. Social support in high-risk adolescents: structural components and adaptive impact.

    PubMed

    Cauce, A M; Felner, R D; Primavera, J

    1982-08-01

    This study examines the structure of social support and its relationship to adjustment for adolescents from high-stress lower socioeconomic class inner-city backgrounds. An attempt is made to (a) identify meaningful dimensions of perceived social support for this population; (b) examine the degree to which the perceived helpfulness of each source of support varied as a function of age, sex, and ethnic background; and (c) determine the relationship between the dimensions of social support, personal characteristics of the adolescent, and indices of personal and academic adjustment. Factor analyses reveal three distinct support dimensions: Family, Formal, and Informal Support. Multivariate and univariate analyses of variance show differences in the perceived helpfulness of the support dimensions as a function of the adolescent's age, sex, and ethnic background as well as in the relationship of each source of support to the adjustment indices. Implications of the findings for elaborating the impact of social support on coping efforts are discussed. PMID:7137129

  14. Mathematical Modeling: A Structured Process

    ERIC Educational Resources Information Center

    Anhalt, Cynthia Oropesa; Cortez, Ricardo

    2015-01-01

    Mathematical modeling, in which students use mathematics to explain or interpret physical, social, or scientific phenomena, is an essential component of the high school curriculum. The Common Core State Standards for Mathematics (CCSSM) classify modeling as a K-12 standard for mathematical practice and as a conceptual category for high school…

  15. Residual Structures in Latent Growth Curve Modeling

    ERIC Educational Resources Information Center

    Grimm, Kevin J.; Widaman, Keith F.

    2010-01-01

    Several alternatives are available for specifying the residual structure in latent growth curve modeling. Two specifications involve uncorrelated residuals and represent the most commonly used residual structures. The first, building on repeated measures analysis of variance and common specifications in multilevel models, forces residual variances…

  16. A Teaching Model for Truss Structures

    ERIC Educational Resources Information Center

    Bigoni, Davide; Dal Corso, Francesco; Misseroni, Diego; Tommasini, Mirko

    2012-01-01

    A classroom demonstration model has been designed, machined and successfully tested in different learning environments to facilitate understanding of the mechanics of truss structures, in which struts are subject to purely axial load and deformation. Gaining confidence with these structures is crucial for the development of lattice models, which…

  17. Advanced development of atmospheric models. [SEASAT Program support

    NASA Technical Reports Server (NTRS)

    Kesel, P. G.; Langland, R. A.; Stephens, P. L.; Welleck, R. E.; Wolff, P. M.

    1979-01-01

    A set of atmospheric analysis and prediction models was developed in support of the SEASAT Program existing objective analysis models which utilize a 125x125 polar stereographic grid of the Northern Hemisphere, which were modified in order to incorporate and assess the impact of (real or simulated) satellite data in the analysis of a two-day meteorological scenario in January 1979. Program/procedural changes included: (1) a provision to utilize winds in the sea level pressure and multi-level height analyses (1000-100 MBS); (2) The capability to perform a pre-analysis at two control levels (1000 MBS and 250 MBS); (3) a greater degree of wind- and mass-field coupling, especially at these controls levels; (4) an improved facility to bogus the analyses based on results of the preanalysis; and (5) a provision to utilize (SIRS) satellite thickness values and cloud motion vectors in the multi-level height analysis.

  18. A community college model to support nursing workforce diversity.

    PubMed

    Colville, Janet; Cottom, Sherry; Robinette, Teresa; Wald, Holly; Waters, Tomi

    2015-02-01

    Community College of Allegheny County (CCAC), Allegheny Campus, is situated on the North Side of Pittsburgh. The neighborhood is 60% African American. At the time of the Health Resources and Services Administration (HRSA) application, approximately one third of the students admitted to the program were African American, less than one third of whom successfully completed it. With the aid of HRSA funding, CCAC developed a model that significantly improved the success rate of disadvantaged students. Through the formation of a viable cohort, the nursing faculty nurtured success among the most at-risk students. The cohort was supported by a social worker, case managers who were nursing faculty, and tutors. Students formed study groups, actively participated in community activities, and developed leadership skills through participation in the Student Nurse Association of Pennsylvania. This article provides the rationale for the Registered Nurse (RN) Achievement Model, describes the components of RN Achievement, and discusses the outcomes of the initiative. PMID:25802900

  19. Mass balances for a biological life support system simulation model

    NASA Technical Reports Server (NTRS)

    Volk, Tyler; Rummel, John D.

    1987-01-01

    Design decisions to aid the development of future space based biological life support systems (BLSS) can be made with simulation models. The biochemistry stoichiometry was developed for: (1) protein, carbohydrate, fat, fiber, and lignin production in the edible and inedible parts of plants; (2) food consumption and production of organic solids in urine, feces, and wash water by the humans; and (3) operation of the waste processor. Flux values for all components are derived for a steady state system with wheat as the sole food source. The large scale dynamics of a materially closed (BLSS) computer model is described in a companion paper. An extension of this methodology can explore multifood systems and more complex biochemical dynamics while maintaining whole system closure as a focus.

  20. Identification of O-rich structures on platinum(111)-supported ultrathin iron oxide films

    NASA Astrophysics Data System (ADS)

    Merte, Lindsay R.; Bai, Yunhai; Zeuthen, Helene; Peng, Guowen; Lammich, Lutz; Besenbacher, Flemming; Mavrikakis, Manos; Wendt, Stefan

    2016-10-01

    Using high-resolution scanning tunneling microscopy (STM) we have studied the oxidation of ultrathin FeO films grown on Pt(111). At the initial stage of the FeO film oxidation by atomic oxygen exposure, we identified three distinct types of line defects, all of which form boundaries between FeO domains of opposite orientation. Two types of line defects appearing bright (type-i) and dark (type-ii) in the STM images at typical scanning parameters are "metallic", whereas the third line defect exhibits nonmetallic behavior (type-iii). Atomic-scale structure models of these line defects are proposed, with type-i defects exhibiting 4-fold coordinated Fe atoms, type-ii exhibiting 2-fold coordinated O atoms, and type-iii exhibiting tetrahedrally-coordinated Fe atoms. In addition, FeO2 trilayer islands are formed upon oxidation, which appear at FCC-type domains of the moiré structure. At high scanning bias, distinct protrusions on the trilayer islands are observed over surface O ions, which are assigned to H adatoms. The experimental data are supported by density functional theory (DFT) calculations, in which bare and hydroxylated FeO2 trilayer islands are compared. Finally, we compare the formation of O-rich features on continuous FeO films using atomic oxygen with the oxidation of Pt(111)-supported FeO islands accomplished by O2 exposure.

  1. Adolescent adjustment in the context of life change: the supportive role of parental structure provision.

    PubMed

    Flamm, Elizabeth S; Grolnick, Wendy S

    2013-10-01

    This study examined the associations among disruptive life events, supportive parenting practices, adolescent self-perceptions, and emotional outcomes. One-hundred and three 7th graders (68% minority, 32% European American) and their parents completed recent negative life events checklists. Parents also reported the total number of major transitions (changes in residences, schools, parent's romantic partners) that adolescents experienced since birth. Life events were related to lower adolescent-reported perceptions of competence and control, higher adolescent-reported depression and behavior problems, and higher parent-reported conduct problems. Regression analyses supported a mediational model in which competence and control perceptions explained relations between adolescent life events and symptomatology. Parental structure-the provision of clear, consistent and predictable rules and expectations-was associated with more adaptive adolescent functioning, especially among girls. Regressions indicated that structure related to higher perceptions of competence and control and fewer behavioral problems, even after accounting for the risk associated with negative life events and transitions. PMID:24011106

  2. Modelling Vague Knowledge for Decision Support in Planning Archaeological Prospections

    NASA Astrophysics Data System (ADS)

    Boos, S.; Hornung, S.; Müller, H.

    2012-07-01

    Most archaeological predictive models lack significance because fuzziness of data and uncertainty in knowledge about human behaviour and natural processes are hardly ever considered. One possibility to cope with such uncertainties is utilization of probability based approaches like Bayes Theorem or Dempster-Shafer-Theory. We analyzed an area of 50 km2 in Rhineland Palatinate (Germany) near a Celtic oppidum by use of Dempster-Shafer's theory of evidence for predicting spatial probability distribution of archaeological sites. This technique incorporates uncertainty by assigning various weights of evidence to defined variables, in that way estimating the probability for supporting a specific hypothesis (in our case the hypothesis presence or absence of a site). Selection of variables for our model relied both on assumptions about settlement patterns and on statistically tested relationships between known archaeological sites and environmental factors. The modelling process was conducted in a Geographic Information System (GIS) by generating raster-based likelihood surfaces. The corresponding likelihood surfaces were aggregated to a final weight of evidence surface, which resulted in a likelihood value for every single cell of being a site or a non-site. Finally the result was tested against a database of known archaeological sites for evaluating the gain of the model. For the purpose of enhancing the gain of our model and sharpening our criteria we used a two-step approach to improve the modelling of former settlement strategies in our study area. Applying the developed model finally yielded a 100 percent success rate of known archaeological sites located in predicted high potential areas.

  3. Ion scattering analysis of alumina supported model catalysts

    NASA Astrophysics Data System (ADS)

    Josek, K.; Linsmeier, Ch.; Knözinger, H.; Taglaucr, E.

    1992-02-01

    The surface of supported oxide and metal catalysts, namely MoO 3/Al 2O 3 or Rh/Al 2O 3, is systematically studied using model systems. For this purpose, plane Al samples were oxidized in different ways and this support material was impregnated from the liquid phase or by evaporation. The elemental depth distribution was examined by low energy ion scattering and sputter etching (ISS) at different primary energies. By fitting Gaussian- or Lorentzian-type functions to the spectra, the use of peak heights or integrals for the interpretation is discussed. The dependence of the peak width on the chemical character is related to inelastic energy losses during scattering. ISS results from model systems are compared with those from real powder catalysts. The surface coverage with the active component was studied by additionally using Auger electron spectroscopy (AES) and Rutherford backscattering spectroscopy (RBS). These methods, combined with energy-dispersive X-ray microanalysis (EDX), lead to an explanation of the adsorption kinetics of molybdate on alumina from aqueous solution by pore-filling.

  4. System structural test results - Six PODS III supports. [Passive Orbital Disconnect Struts

    NASA Technical Reports Server (NTRS)

    Parmley, Richard T.; Kittel, Peter

    1986-01-01

    Passive orbital disconnect struts can potentially reduce the support conductance a factor of 10 over state-of-the-art tension band nondisconnect supports and cut helium dewar weights in half for the same lifetime. A series of thermal and structural tests were performed to verify that this performance improvement is real. Structural tests on a PODS-III support system (consisting of six struts) is reported here. The results show the predicted performance improvements can be achieved and the PODS-III supports are ready for flight applications. For large tankage systems requiring higher side load capability, a PODS-IV version is currently being developed.

  5. A study of aeroelastic stability for the model support system of the National Transonic Facility

    NASA Technical Reports Server (NTRS)

    Strganac, Thomas W.

    1988-01-01

    Oscillations of wind-tunnel models have been observed during testing in the National Transonic Facility. These oscillations have been the subject of an extensive investigation. As a part of this effort, a study of the aeroelastic stability of the model support structure has been performed. This structure is mathematically modelled as a wing and conventional flutter analysis is performed. The math model implemented both experimentally and numerically obtained modal characteristics. A technique for illustrating the flutter boundary for wind tunnels is demonstrated. Results indicate that the classical flutter boundary is well above the operating envelope of the facility. However, the analysis indicates a damping-dependent instability is present which is inherent in the design. One possible modification in the design has been evaluated which eliminates the predicted instability.

  6. Modeling studies in support of the IMHEX MCFC commercialization

    SciTech Connect

    Jewulski, J.R.; Resnick, G.L.; Hu, W.C.S.

    1998-07-01

    Performance modeling studies are a necessary and cost effective element of the IMHEX-MCFC stack commercialization. Technologix Corporation, in cooperation with M-C Power, has developed the algorithms and computer code for two of the models in addition to modifying the PSI model for applications specific to IMHEX fuel cell concept. Three performance models support the product development effort: a modified PSI model; a two-dimensional cross-flow cell model and a three-dimensional stack model. The sizing, number and location of the stack inter-coolers in a fuel cell stack are typical model application. Recently M-C Power modified its stack configuration to cross-flow. The cross-flow allows simplified repeat parts manufacturing and reduces the risk of gas crossover. The MCFC cross-flow model developed at M-C Power supports heat loss from the stack edges, variable fuel flow rate regions and variable oxidant flow rate regions (coupled with the optimization module) among other features. Extensive computational experiments were conducted in support of the cross-flow geometry development for the MCFC stack. The oxidant flow distribution optimization was used to mitigate the hardware temperature hot-spot typical for the cross-flow geometry. The hardware temperature hot-spot increases corrosion rate, electrolyte loss, and leads to deterioration of the long-term MCFC stack performance. Under the normal operating conditions, the maximum local temperature of the cell hardware should not exceed 960 K. The mathematical optimization software was applied to find the optimum flow distribution. The minimization of the maximum hardware temperature was defined as an optimization goal. The gas flow rate in each region was selected as independent variable subjected to optimization. In some cases the authors have also added a distance between the fuel inlet and the flow region divider to the list of independent variables. The total gas flow rates, inlet gas temperatures and compositions

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

    USGS Publications Warehouse

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

    2002-01-01

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

  8. Modeling Global Urbanization Supported by Nighttime Light Remote Sensing

    NASA Astrophysics Data System (ADS)

    Zhou, Y.

    2015-12-01

    Urbanization, a major driver of global change, profoundly impacts our physical and social world, for example, altering carbon cycling and climate. Understanding these consequences for better scientific insights and effective decision-making unarguably requires accurate information on urban extent and its spatial distributions. In this study, we developed a cluster-based method to estimate the optimal thresholds and map urban extents from the nighttime light remote sensing data, extended this method to the global domain by developing a computational method (parameterization) to estimate the key parameters in the cluster-based method, and built a consistent 20-year global urban map series to evaluate the time-reactive nature of global urbanization (e.g. 2000 in Fig. 1). Supported by urban maps derived from nightlights remote sensing data and socio-economic drivers, we developed an integrated modeling framework to project future urban expansion by integrating a top-down macro-scale statistical model with a bottom-up urban growth model. With the models calibrated and validated using historical data, we explored urban growth at the grid level (1-km) over the next two decades under a number of socio-economic scenarios. The derived spatiotemporal information of historical and potential future urbanization will be of great value with practical implications for developing adaptation and risk management measures for urban infrastructure, transportation, energy, and water systems when considered together with other factors such as climate variability and change, and high impact weather events.

  9. Agricultural Model for the Nile Basin Decision Support System

    NASA Astrophysics Data System (ADS)

    van der Bolt, Frank; Seid, Abdulkarim

    2014-05-01

    To analyze options for increasing food supply in the Nile basin the Nile Agricultural Model (AM) was developed. The AM includes state-of-the-art descriptions of biophysical, hydrological and economic processes and realizes a coherent and consistent integration of hydrology, agronomy and economics. The AM covers both the agro-ecological domain (water, crop productivity) and the economic domain (food supply, demand, and trade) and allows to evaluate the macro-economic and hydrological impacts of scenarios for agricultural development. Starting with the hydrological information from the NileBasin-DSS the AM calculates the available water for agriculture, the crop production and irrigation requirements with the FAO-model AquaCrop. With the global commodity trade model MAGNET scenarios for land development and conversion are evaluated. The AM predicts consequences for trade, food security and development based on soil and water availability, crop allocation, food demand and food policy. The model will be used as a decision support tool to contribute to more productive and sustainable agriculture in individual Nile countries and the whole region.

  10. Breaking wave impact forces on truss support structures for offshore wind turbines

    NASA Astrophysics Data System (ADS)

    Cieślikiewicz, Witold; Gudmestad, Ove T.; Podrażka, Olga

    2014-05-01

    Due to depletion of the conventional energy sources, wind energy is becoming more popular these days. Wind energy is being produced mostly from onshore farms, but there is a clear tendency to transfer wind farms to the sea. The foundations of offshore wind turbines may be truss structures and might be located in shallow water, where are subjected to highly varying hydrodynamic loads, particularly from plunging breaking waves. There are models for impact forces prediction on monopiles. Typically the total wave force on slender pile from breaking waves is a superposition of slowly varying quasi-static force, calculated from the Morison equation and additional dynamical, short duration force due to the impact of the breaker front or breaker tongue. There is not much research done on the truss structures of wind turbines and there are still uncertainties on slamming wave forces, due to plunging breaking waves on those structures. Within the WaveSlam (Wave slamming forces on truss structures in shallow water) project the large scale tests were carried out in 2013 at the Large Wave Flume in Forschungszentrum Küste (FZK) in Hannover, Germany. The following institutions participated in this initiative: the University of Stavanger and the Norwegian University of Science and Technology (project management), University of Gdańsk, Poland, Hamburg University of Technology and the University of Rostock, Germany and Reinertsen AS, Norway. This work was supported by the EU 7th Framework Programme through the grant to the budget of the Integrating Activity HYDRALAB IV. The main aim of the experiment was to investigate the wave slamming forces on truss structures, development of new and improvement of existing methods to calculate forces from the plunging breakers. The majority of the measurements were carried out for regular waves with specified frequencies and wave heights as well as for the irregular waves based on JONSWAP spectrum. The truss structure was equipped with both

  11. Model verification of large structural systems. [space shuttle model response

    NASA Technical Reports Server (NTRS)

    Lee, L. T.; Hasselman, T. K.

    1978-01-01

    A computer program for the application of parameter identification on the structural dynamic models of space shuttle and other large models with hundreds of degrees of freedom is described. Finite element, dynamic, analytic, and modal models are used to represent the structural system. The interface with math models is such that output from any structural analysis program applied to any structural configuration can be used directly. Processed data from either sine-sweep tests or resonant dwell tests are directly usable. The program uses measured modal data to condition the prior analystic model so as to improve the frequency match between model and test. A Bayesian estimator generates an improved analytical model and a linear estimator is used in an iterative fashion on highly nonlinear equations. Mass and stiffness scaling parameters are generated for an improved finite element model, and the optimum set of parameters is obtained in one step.

  12. Three Dimensional Response Spectrum Soil Structure Modeling Versus Conceptual Understanding To Illustrate Seismic Response Of Structures

    SciTech Connect

    Touqan, Abdul Razzaq

    2008-07-08

    Present methods of analysis and mathematical modeling contain so many assumptions that separate them from reality and thus represent a defect in design which makes it difficult to analyze reasons of failure. Three dimensional (3D) modeling is so superior to 1D or 2D modeling, static analysis deviates from the true nature of earthquake load which is 'a dynamic punch', and conflicting assumptions exist between structural engineers (who assume flexible structures on rigid block foundations) and geotechnical engineers (who assume flexible foundations supporting rigid structures). Thus a 3D dynamic soil-structure interaction is a step that removes many of the assumptions and thus clears reality to a greater extent. However such a model cannot be analytically analyzed. We need to anatomize and analogize it. The paper will represent a conceptual (analogical) 1D model for soil structure interaction and clarifies it by comparing its outcome with 3D dynamic soil-structure finite element analysis of two structures. The aim is to focus on how to calculate the period of the structure and to investigate effect of variation of stiffness on soil-structure interaction.

  13. Tree-Structured Digital Organisms Model

    NASA Astrophysics Data System (ADS)

    Suzuki, Teruhiko; Nobesawa, Shiho; Tahara, Ikuo

    Tierra and Avida are well-known models of digital organisms. They describe a life process as a sequence of computation codes. A linear sequence model may not be the only way to describe a digital organism, though it is very simple for a computer-based model. Thus we propose a new digital organism model based on a tree structure, which is rather similar to the generic programming. With our model, a life process is a combination of various functions, as if life in the real world is. This implies that our model can easily describe the hierarchical structure of life, and it can simulate evolutionary computation through mutual interaction of functions. We verified our model by simulations that our model can be regarded as a digital organism model according to its definitions. Our model even succeeded in creating species such as viruses and parasites.

  14. Urban modeling over Houston in support of SIMMER

    NASA Astrophysics Data System (ADS)

    Barlage, M. J.; Monaghan, A. J.; Feddema, J. J.; Oleson, K. W.; Brunsell, N. A.; Wilhelmi, O.

    2011-12-01

    Extreme heat is a leading cause of weather-related human mortality in the United States. As global warming patterns continue, researchers anticipate increases in the severity, frequency and duration of extreme heat events, especially in the southern and western U.S. Many cities in these regions may have amplified vulnerability due to their rapidly evolving socioeconomic fabric (for example, growing elderly populations). This raises a series of questions about the increased health risks of urban residents to extreme heat, and about effective means of mitigation and adaptation in present and future climates. We will introduce a NASA-funded project aimed at addressing these questions via the System for Integrated Modeling of Metropolitan Extreme Heat Risk (SIMMER). Through SIMMER, we hope to advance methodology for assessing current and future urban vulnerabilities from the heat waves through the refinement and integration of physical and social science models, and to build local capacity for heat hazard mitigation and climate change adaptation in the public health sector. We will also present results from a series of sensitivity studies over Houston and surrounding area employing a recently-implemented multi-layer urban canopy model (UCM) within the Noah Land Surface Model. The UCM has multiple layers in the atmosphere to explicitly resolve the effects of buildings, and has an indoor-outdoor exchange model that directly interacts with the atmospheric boundary layer. The goal of this work, which supports the physical science component of SIMMER, is to characterize the ill-defined and uncertain parameter space, including building characteristics and spatial organization, in the new multi-layer UCM for Houston, and to assess whether and how this parameter space is sensitive to the choice of urban morphology datasets. Results focus on the seasonal and inter-annual range of both the modeled urban heat island effect and the magnitude of surface energy components and

  15. Internal structure of laser supported detonation waves by two-wavelength Mach-Zehnder interferometer

    SciTech Connect

    Shimamura, Kohei; Kawamura, Koichi; Fukuda, Akio; Wang Bin; Yamaguchi, Toshikazu; Komurasaki, Kimiya; Hatai, Keigo; Fukui, Akihiro; Arakawa, Yoshihiro

    2011-04-15

    Characteristics of the internal structure of the laser supported detonation (LSD) waves, such as the electron density n{sub e} and the electron temperature T{sub e} profiles behind the shock wave were measured using a two-wavelength Mach-Zehnder interferometer along with emission spectroscopy. A TEA CO{sub 2} laser with energy of 10 J/pulse produced explosive laser heating in atmospheric air. Results show that the peak values of n{sub e} and T{sub e} were, respectively, about 2 x 10{sup 24} m{sup -3} and 30 000 K, during the LSD regime. The temporal variation of the laser absorption coefficient profile estimated from the measured properties reveals that the laser energy was absorbed perfectly in a thin layer behind the shock wave during the LSD regime, as predicted by Raizer's LSD model. However, the absorption layer was much thinner than a plasma layer, the situation of which was not considered in Raizer's model. The measured n{sub e} at the shock front was not zero while the LSD was supported, which implies that the precursor electrons exist ahead of the shock wave.

  16. Biotic origin for Mima mounds supported by numerical modeling

    NASA Astrophysics Data System (ADS)

    Gabet, Emmanuel J.; Perron, J. Taylor; Johnson, Donald L.

    2014-02-01

    Mima mounds are ~ 1-m-high hillocks found on every continent except Antarctica. Despite often numbering in the millions within a single field, their origin has been a mystery, with proposed explanations ranging from glacial processes to seismic shaking. One hypothesis proposes that mounds in North America are built by burrowing mammals to provide refuge from seasonally saturated soils. We test this hypothesis with a numerical model, parameterized with measurements of soil transport by gophers from a California mound field, that couples animal behavior with geomorphic processes. The model successfully simulates the development of the mounds as well as key details such as the creation of vernal pools, small intermound basins that provide habitat for endemic species. Furthermore, we demonstrate that the spatial structure of the modeled mound fields is similar to actual mound fields and provides an example of self-organized topographic features. We conclude that, scaled by body mass, Mima mounds are the largest structures built by nonhuman mammals and may provide a rare example of an evolutionary coupling between landforms and the organisms that create them.

  17. Biotic Origin for Mima Mounds Supported by Numerical Model

    NASA Astrophysics Data System (ADS)

    Gabet, E. J.; Perron, J.; Johnson, D. L.

    2013-12-01

    Mima mounds are ~1-m-high hillocks found on every continent except Antarctica. Despite often numbering in the millions within a single field, their origin has been a mystery, with proposed explanations ranging from glacial processes to seismic shaking. One hypothesis proposes that mounds in North America are built by burrowing mammals to provide refuge from seasonally saturated soils. We test this hypothesis with a numerical model, parameterized with measurements of soil transport by gophers from a California mound field, that couples animal behavior with geomorphic processes. The model successfully simulates the development of the mounds, as well as key details such as the creation of vernal pools, small intermound basins that provide habitat for endemic species. Furthermore, we demonstrate that the spatial structure of the modeled mound fields is similar to actual mound fields and provides an example of self-organized topographic features. We conclude that, scaled by body mass, Mima mounds are the largest structures built by non-human mammals, and may provide a rare example of an evolutionary coupling between landforms and the organisms that create them.

  18. Modeling of Multipacting in RF Structures Using VORPAL

    NASA Astrophysics Data System (ADS)

    Nieter, Chet; Stoltz, Peter H.; Roark, Christine; Mahalingam, Sudhakar

    2010-11-01

    VORPAL is a simulation framework which can model electromagnetic fields and charged particle dynamics in RF structures such as those encountered in high gradient accelerating cavities. Multiple models exist in VORPAL to determine the secondary electron yield (SEY) for an impact of a primary electron on the cavity surface. Combining these models allows VORPAL to be used to study electron multipacting in radio frequency cavity structures. VORPAL also supports the tracking of individual multipacting trajectories as well as recording the impact history of multipacting electrons. We present simulation results of multipacting simulations in various RF structures including accelerating cavities as well as coupler and waveguide structures. Benchmarking results are given comparing VORPAL results from other codes as well as experimental data.

  19. Structured statistical models of inductive reasoning.

    PubMed

    Kemp, Charles; Tenenbaum, Joshua B

    2009-01-01

    Everyday inductive inferences are often guided by rich background knowledge. Formal models of induction should aim to incorporate this knowledge and should explain how different kinds of knowledge lead to the distinctive patterns of reasoning found in different inductive contexts. This article presents a Bayesian framework that attempts to meet both goals and describes [corrected] 4 applications of the framework: a taxonomic model, a spatial model, a threshold model, and a causal model. Each model makes probabilistic inferences about the extensions of novel properties, but the priors for the 4 models are defined over different kinds of structures that capture different relationships between the categories in a domain. The framework therefore shows how statistical inference can operate over structured background knowledge, and the authors argue that this interaction between structure and statistics is critical for explaining the power and flexibility of human reasoning. PMID:19159147

  20. Condensed Antenna Structural Models for Dynamics Analysis

    NASA Technical Reports Server (NTRS)

    Levy, R.

    1985-01-01

    Condensed degree-of-freedom models are compared with large degree-of-freedom finite-element models of a representative antenna-tipping and alidade structure, for both locked and free-rotor configurations. It is shown that: (1) the effective-mass models accurately reproduce the lower-mode natural frequencies of the finite element model; (2) frequency responses for the two types of models are in agreement up to at least 16 rad/s for specific points; and (3) transient responses computed for the same points are in good agreement. It is concluded that the effective-mass model, which best represents the five lower modes of the finite-element model, is a sufficient representation of the structure for future incorporation with a total servo control structure dynamic simulation.

  1. The major autoantibody epitope on factor H in atypical hemolytic uremic syndrome is structurally different from its homologous site in factor H-related protein 1, supporting a novel model for induction of autoimmunity in this disease.

    PubMed

    Bhattacharjee, Arnab; Reuter, Stefanie; Trojnár, Eszter; Kolodziejczyk, Robert; Seeberger, Harald; Hyvärinen, Satu; Uzonyi, Barbara; Szilágyi, Ágnes; Prohászka, Zoltán; Goldman, Adrian; Józsi, Mihály; Jokiranta, T Sakari

    2015-04-10

    Atypical hemolytic uremic syndrome (aHUS) is characterized by complement attack against host cells due to mutations in complement proteins or autoantibodies against complement factor H (CFH). It is unknown why nearly all patients with autoimmune aHUS lack CFHR1 (CFH-related protein-1). These patients have autoantibodies against CFH domains 19 and 20 (CFH19-20), which are nearly identical to CFHR1 domains 4 and 5 (CFHR14-5). Here, binding site mapping of autoantibodies from 17 patients using mutant CFH19-20 constructs revealed an autoantibody epitope cluster within a loop on domain 20, next to the two buried residues that are different in CFH19-20 and CFHR14-5. The crystal structure of CFHR14-5 revealed a difference in conformation of the autoantigenic loop in the C-terminal domains of CFH and CFHR1, explaining the variation in binding of autoantibodies from some aHUS patients to CFH19-20 and CFHR14-5. The autoantigenic loop on CFH seems to be generally flexible, as its conformation in previously published structures of CFH19-20 bound to the microbial protein OspE and a sialic acid glycan is somewhat altered. Cumulatively, our data suggest that association of CFHR1 deficiency with autoimmune aHUS could be due to the structural difference between CFHR1 and the autoantigenic CFH epitope, suggesting a novel explanation for CFHR1 deficiency in the pathogenesis of autoimmune aHUS. PMID:25659429

  2. Multiplicity Control in Structural Equation Modeling

    ERIC Educational Resources Information Center

    Cribbie, Robert A.

    2007-01-01

    Researchers conducting structural equation modeling analyses rarely, if ever, control for the inflated probability of Type I errors when evaluating the statistical significance of multiple parameters in a model. In this study, the Type I error control, power and true model rates of famsilywise and false discovery rate controlling procedures were…

  3. A Cu4S Model for the Nitrous Oxide Reductase Active Sites Supported Only by Nitrogen Ligands†

    PubMed Central

    Johnson, Brittany J.; Antholine, William E.; Lindeman, Sergey V.; Mankad, Neal P.

    2016-01-01

    To model the (His)7Cu4Sn (n = 1 or 2) active sites of nitrous oxide reductase, the first Cu4(μ4-S) cluster supported only by nitrogen donors has been prepared using amidinate supporting ligands. Structural, magnetic, spectroscopic, and computational characterization is reported. Electrochemical data indicates that the 2-hole model complex can be reduced reversibly to the 1-hole state and irreversibly to the fully reduced state. PMID:26111160

  4. A Cu4S model for the nitrous oxide reductase active sites supported only by nitrogen ligands.

    PubMed

    Johnson, Brittany J; Antholine, William E; Lindeman, Sergey V; Mankad, Neal P

    2015-07-28

    To model the (His)7Cu4Sn (n = 1 or 2) active sites of nitrous oxide reductase, the first Cu4(μ4-S) cluster supported only by nitrogen donors has been prepared using amidinate supporting ligands. Structural, magnetic, spectroscopic, and computational characterization is reported. Electrochemical data indicates that the 2-hole model complex can be reduced reversibly to the 1-hole state and irreversibly to the fully reduced state. PMID:26111160

  5. Modeling snail breeding in a bioregenerative life support system

    NASA Astrophysics Data System (ADS)

    Kovalev, V. S.; Manukovsky, N. S.; Tikhomirov, A. A.; Kolmakova, A. A.

    2015-07-01

    The discrete-time model of snail breeding consists of two sequentially linked submodels: "Stoichiometry" and "Population". In both submodels, a snail population is split up into twelve age groups within one year of age. The first submodel is used to simulate the metabolism of a single snail in each age group via the stoichiometric equation; the second submodel is used to optimize the age structure and the size of the snail population. Daily intake of snail meat by crewmen is a guideline which specifies the population productivity. The mass exchange of the snail unit inhabited by land snails of Achatina fulica is given as an outcome of step-by-step modeling. All simulations are performed using Solver Add-In of Excel 2007.

  6. Modeling snail breeding in a bioregenerative life support system.

    PubMed

    Kovalev, V S; Manukovsky, N S; Tikhomirov, A A; Kolmakova, A A

    2015-07-01

    The discrete-time model of snail breeding consists of two sequentially linked submodels: "Stoichiometry" and "Population". In both submodels, a snail population is split up into twelve age groups within one year of age. The first submodel is used to simulate the metabolism of a single snail in each age group via the stoichiometric equation; the second submodel is used to optimize the age structure and the size of the snail population. Daily intake of snail meat by crewmen is a guideline which specifies the population productivity. The mass exchange of the snail unit inhabited by land snails of Achatina fulica is given as an outcome of step-by-step modeling. All simulations are performed using Solver Add-In of Excel 2007. PMID:26256627

  7. Aggregation of Environmental Model Data for Decision Support

    NASA Astrophysics Data System (ADS)

    Alpert, J. C.

    2013-12-01

    model output offering access to probability and calibrating information for real time decision making. The aggregation content server reports over ensemble component and forecast time in addition to the other data dimensions of vertical layer and position for each variable. The unpacking, organization and reading of many binary packed files is accomplished most efficiently on the server while weather element event probability calculations, the thresholds for more accurate decision support, or display remain for the client. Our goal is to reduce uncertainty for variables of interest, e.g, agricultural importance. The weather service operational GFS model ensemble and short range ensemble forecasts can make skillful probability forecasts to alert users if and when their selected weather events will occur. A description of how this framework operates and how it can be implemented using existing NOMADS content services and applications is described.

  8. Frequency domain modelling of wind turbine structures

    SciTech Connect

    Soerensen, P.; Larsen, G.C.; Christensen, C.J.

    1995-09-01

    The present paper describes a frequency domain model of the structure of an operating horizontal axis wind turbine. The frequency domain model is implemented along with an analogous time domain modeling the Risoe PC code Design Basis 2, and a more detailed description of the model is offered in a Risoe report by Soerensen (1994). The structure of an operating wind turbine is affected by essential non-linearities between structural variables on blades and tower respectively. These non-linearities are caused by the rotation of the blades. The transformations between the blade coordinate systems and the tower coordinate system will depend on the instantaneous azimuth positions of the blades as they rotate. Frequency domain analysis are much faster than time simulations and in some respects they give more insight into the dynamics of the structure. However, the non-linear terms in the dynamic equations for a complex wind turbine structure are usually thought to preclude the use of frequency domain methods. Design Basis 2 is used to verify the frequency domain model comparing loads on the structure calculated with the frequency domain model both to loads calculated with the time domain model and to measured loads. Examples show that frequency and time domain calculations of typical PSD`s of loads are in very good agreement. Also the agreement between the calculated and measured PSD`s is good. Moreover, Design Basis 2 has shown that the frequency domain model results in an extremely fast calculation method.

  9. Intelligent-based Structural Damage Detection Model

    SciTech Connect

    Lee, Eric Wai Ming; Yu, K.F.

    2010-05-21

    This paper presents the application of a novel Artificial Neural Network (ANN) model for the diagnosis of structural damage. The ANN model, denoted as the GRNNFA, is a hybrid model combining the General Regression Neural Network Model (GRNN) and the Fuzzy ART (FA) model. It not only retains the important features of the GRNN and FA models (i.e. fast and stable network training and incremental growth of network structure) but also facilitates the removal of the noise embedded in the training samples. Structural damage alters the stiffness distribution of the structure and so as to change the natural frequencies and mode shapes of the system. The measured modal parameter changes due to a particular damage are treated as patterns for that damage. The proposed GRNNFA model was trained to learn those patterns in order to detect the possible damage location of the structure. Simulated data is employed to verify and illustrate the procedures of the proposed ANN-based damage diagnosis methodology. The results of this study have demonstrated the feasibility of applying the GRNNFA model to structural damage diagnosis even when the training samples were noise contaminated.

  10. Structuring temporal sequences: comparison of models and factors of complexity.

    PubMed

    Essens, P

    1995-05-01

    Two stages for structuring tone sequences have been distinguished by Povel and Essens (1985). In the first, a mental clock segments a sequence into equal time units (clock model); in the second, intervals are specified in terms of subdivisions of these units. The present findings support the clock model in that it predicts human performance better than three other algorithmic models. Two further experiments in which clock and subdivision characteristics were varied did not support the hypothesized effect of the nature of the subdivisions on complexity. A model focusing on the variations in the beat-anchored envelopes of the tone clusters was proposed. Errors in reproduction suggest a dual-code representation comprising temporal and figural characteristics. The temporal part of the representation is based on the clock model but specifies, in addition, the metric of the level below the clock. The beat-tone-cluster envelope concept was proposed to specify the figural part. PMID:7596749

  11. A point defect model for nickel electrode structures

    NASA Technical Reports Server (NTRS)

    Loyselle, Patricia L.; Karjala, Philip J.; Cornilsen, Bahne C.

    1986-01-01

    The Raman spectra for nickel electrode active mass indicate a single formula-unit crystallographic unit cell of the layered NiOOH-type. Empirical stoichiometric formulas require that extensive point defects, cation dopants and nickel vacancies, be incorporated on nickel sites. Structural differences between the alpha/gamma and beta/beta cycles, and the influence of cobalt addition on the structure will be discussed in terms of the point defect model. Other empirical data supporting the point defect model will be considered.

  12. Nurse manager support: what is it? Structures and practices that promote it.

    PubMed

    Kramer, Marlene; Maguire, Patricia; Schmalenberg, Claudia; Brewer, Barbara; Burke, Rebecca; Chmielewski, Linda; Cox, Karen; Kishner, Janice; Krugman, Mary; Meeks-Sjostrom, Diana; Waldo, Mary

    2007-01-01

    Professional nursing organizations identify nurse manager (NM) support of staff nurses as an essential component of a productive, healthy work environment. Role behaviors that constitute this support must be identified by staff nurses. In this mixed-method study, supportive role behaviors were identified by 2382 staff nurses who completed the investigator-developed Nurse Manager Support Scale. In addition, semistructured interviews were conducted with 446 staff nurses, managers, and physicians from 101 clinical units in 8 Magnet hospitals in which staff nurses had previously confirmed excellent nurse manager support. Through individual and focus group interviews with NM and chief nurse executives in the 8 participating hospitals, the organizational structures and practices that enabled NM to be supportive to staff were determined. The 9 most supportive role behaviors cited by interviewees were as follows: is approachable and safe, cares, "walks the talk," motivates development of self-confidence, gives genuine feedback, provides adequate and competent staffing, "watches our back," promotes group cohesion and teamwork, and resolves conflicts constructively. Supporting structures and programs identified by managers and leaders include the following: "support from the top," peer group support, educational programs and training sessions, a "lived" culture, secretarial or administrative assistant support, private office space, and computer classes and seminars. PMID:17909432

  13. Simulation modeling of supported lipid membranes - a review.

    PubMed

    Hirtz, Michael; Kumar, Naresh; Chi, Lifeng

    2014-03-01

    Lipid membranes are of great importance for many biological systems and biotechnological applications. One method to gain a profound understanding of the dynamics in lipid membranes and their interaction with other system components is by modeling these systems by computer simulations. Many different approaches have been undertaken in this endeavor that have led to molecular level insights into the underlying mechanisms of several experimental observations and biological processes with an extremely high temporal resolution. As compared to the free-standing lipid bilayers, there are fewer simulation studies addressing the systems of supported lipid membranes. Nevertheless, these have significantly enhanced our understanding of the behavior of lipid layers employed in applications spanning from biosensors to drug delivery and for biological processes such as the breathing cycle of lung surfactants. In this review, we give an account of the state of the art of methods and applications of the simulations of supported lipid bilayers, interfacial membranes at the air/water interface and on solid surfaces. PMID:24444165

  14. Information Integration to Support Model-Based Policy Informatics

    PubMed Central

    Barrett, Christopher L.; Eubank, Stephen; Marathe, Achla; Marathe, Madhav V.; Pan, Zhengzheng; Swarup, Samarth

    2011-01-01

    The complexities of social and technological policy domains, such as the economy, the environment, and public health present challenges that require a new approach to modeling and decision making. The information required for effective policy and decision making in these complex domains is massive in scale, fine-grained in resolution, and distributed over many data sources. Thus, one of the key challenges in building systems to support policy informatics is information integration. We describe our approach to this problem, and how we are building a multi-theory, multi-actor, multi-perspective system that supports continual data uptake, state assessment, decision analysis, and action assignment based on large-scale high-performance computing infrastructures. Our simulation-based approach allows rapid course-of-action analysis to bound variances in outcomes of policy interventions, which in turn allows the short time-scale planning required in response to emergencies such as epidemic outbreaks. We present the rationale and design of our methodology and discuss several areas of actual and potential application. PMID:22337756

  15. Progressor: social navigation support through open social student modeling

    NASA Astrophysics Data System (ADS)

    Hsiao, I.-Han; Bakalov, Fedor; Brusilovsky, Peter; König-Ries, Birgitta

    2013-06-01

    The increased volumes of online learning content have produced two problems: how to help students to find the most appropriate resources and how to engage them in using these resources. Personalized and social learning have been suggested as potential ways to address these problems. Our work presented in this paper combines the ideas of personalized and social learning in the context of educational hypermedia. We introduce Progressor, an innovative Web-based tool based on the concepts of social navigation and open student modeling that helps students to find the most relevant resources in a large collection of parameterized self-assessment questions on Java programming. We have evaluated Progressor in a semester-long classroom study, the results of which are presented in this paper. The study confirmed the impact of personalized social navigation support provided by the system in the target context. The interface encouraged students to explore more topics attempting more questions and achieving higher success rates in answering them. A deeper analysis of the social navigation support mechanism revealed that the top students successfully led the way to discovering most relevant resources by creating clear pathways for weaker students.

  16. Some advances in experimentation supporting development of viscoplastic constitutive models

    NASA Technical Reports Server (NTRS)

    Ellis, J. R.; Robinson, D. N.

    1985-01-01

    The development of a biaxial extensometer capable of measuring axial, torsion, and diametral strains to near-microstrain resolution at elevated temperatures is discussed. An instrument with this capability was needed to provide experimental support to the development of viscoplastic constitutive models. The advantages gained when torsional loading is used to investigate inelastic material response at elevated temperatures are highlighted. The development of the biaxial extensometer was conducted in two stages. The first involved a series of bench calibration experiments performed at room temperature. The second stage involved a series of in-place calibration experiments conducted at room and elevated temperature. A review of the calibration data indicated that all performance requirements regarding resolution, range, stability, and crosstalk had been met by the subject instrument over the temperature range of interest, 21 C to 651 C. The scope of the in-place calibration experiments was expanded to investigate the feasibility of generating stress relaxation data under torsional loading.

  17. Some advances in experimentation supporting development of viscoplastic constitutive models

    NASA Technical Reports Server (NTRS)

    Ellis, J. R.; Robinson, D. N.

    1985-01-01

    The development of a biaxial extensometer capable of measuring axial, torsion, and diametral strains to near-microstrain resolution at elevated temperatures is discussed. An instrument with this capability was needed to provide experimental support to the development of viscoplastic constitutive models. The advantages gained when torsional loading is used to investigate inelastic material response at elevated temperatures are highlighted. The development of the biaxial extensometer was conducted in two stages. The first involved a series of bench calibration experiments performed at room temperature. The second stage involved a series of in-place calibration experiments performed at room temperature. A review of the calibration data indicated that all performance requirements regarding resolution, range, stability, and crosstalk had been met by the subject instrument over the temperature range of interest, 21 C to 651 C. The scope of the in-placed calibration experiments was expanded to investigate the feasibility of generating stress relaxation data under torsional loading.

  18. An Individual-Oriented Model on the Emergence of Support in Fights, Its Reciprocation and Exchange

    PubMed Central

    Hemelrijk, Charlotte K.; Puga-Gonzalez, Ivan

    2012-01-01

    Complex social behaviour of primates has usually been attributed to the operation of complex cognition. Recently, models have shown that constraints imposed by the socio-spatial structuring of individuals in a group may result in an unexpectedly high number of patterns of complex social behaviour, resembling the dominance styles of egalitarian and despotic species of macaques and the differences between them. This includes affiliative patterns, such as reciprocation of grooming, grooming up the hierarchy, and reconciliation. In the present study, we show that the distribution of support in fights, which is the social behaviour that is potentially most sophisticated in terms of cognitive processes, may emerge in the same way. The model represents the spatial grouping of individuals and their social behaviour, such as their avoidance of risks during attacks, the self-reinforcing effects of winning and losing their fights, their tendency to join in fights of others that are close by (social facilitation), their tendency to groom when they are anxious, the reduction of their anxiety by grooming, and the increase of anxiety when involved in aggression. Further, we represent the difference in intensity of aggression apparent in egalitarian and despotic macaques. The model reproduces many aspects of support in fights, such as its different types, namely, conservative, bridging and revolutionary, patterns of choice of coalition partners attributed to triadic awareness, those of reciprocation of support and ‘spiteful acts’ and of exchange between support and grooming. This work is important because it suggests that behaviour that seems to result from sophisticated cognition may be a side-effect of spatial structure and dominance interactions and it shows that partial correlations fail to completely omit these effects of spatial structure. Further, the model is falsifiable, since it results in many patterns that can easily be tested in real primates by means of existing

  19. An individual-oriented model on the emergence of support in fights, its reciprocation and exchange.

    PubMed

    Hemelrijk, Charlotte K; Puga-Gonzalez, Ivan

    2012-01-01

    Complex social behaviour of primates has usually been attributed to the operation of complex cognition. Recently, models have shown that constraints imposed by the socio-spatial structuring of individuals in a group may result in an unexpectedly high number of patterns of complex social behaviour, resembling the dominance styles of egalitarian and despotic species of macaques and the differences between them. This includes affiliative patterns, such as reciprocation of grooming, grooming up the hierarchy, and reconciliation. In the present study, we show that the distribution of support in fights, which is the social behaviour that is potentially most sophisticated in terms of cognitive processes, may emerge in the same way. The model represents the spatial grouping of individuals and their social behaviour, such as their avoidance of risks during attacks, the self-reinforcing effects of winning and losing their fights, their tendency to join in fights of others that are close by (social facilitation), their tendency to groom when they are anxious, the reduction of their anxiety by grooming, and the increase of anxiety when involved in aggression. Further, we represent the difference in intensity of aggression apparent in egalitarian and despotic macaques. The model reproduces many aspects of support in fights, such as its different types, namely, conservative, bridging and revolutionary, patterns of choice of coalition partners attributed to triadic awareness, those of reciprocation of support and 'spiteful acts' and of exchange between support and grooming. This work is important because it suggests that behaviour that seems to result from sophisticated cognition may be a side-effect of spatial structure and dominance interactions and it shows that partial correlations fail to completely omit these effects of spatial structure. Further, the model is falsifiable, since it results in many patterns that can easily be tested in real primates by means of existing data

  20. Effects of shaft supporting structure on performance test of axial flow fan

    NASA Astrophysics Data System (ADS)

    Ma, R.; Liu, S. L.; Li, M. X.; Zheng, S. Y.

    2016-05-01

    CFD numerical simulation combined with theoretical analysis are used to research and discuss the obstructing effect, caused by the supporting structure of torsion meter and connecting shaft, on the outlet airflow of axial-flow fan in type-C ducted inlet device. The relations between axial flow fan's total pressure efficiency and flow rate are studied when the distance between supporting structure and outlet section is different, which may provide a reference for the proper design of the performance test device.

  1. Thermal behaviour of a periodic structure supported by dielectric rods in vacuum

    NASA Astrophysics Data System (ADS)

    Gahlaut, V.; Alvi, P. A.; Ghosh, S.

    2014-06-01

    In a traveling-wave tube (TWT) the helical periodic slow-wave structure (SWS) is supported by dielectric supports in a metal envelope in high vacuum. The heat generated in the helix during beam-wave interaction, restricts the average power handling capability of a TWT, dissipated by conduction through support rods. Thermal contact resistances, arises at different joints of different materials, affect heat dissipation from the helix which have been studied and presented here.

  2. Forebay Computational Fluid Dynamics Modeling for The Dalles Dam to Support Behavior Guidance System Siting Studies

    SciTech Connect

    Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.; Johnson, Gary E.

    2005-03-10

    Computational fluid dynamics (CFD) models were developed to support the siting and design of a behavioral guidance system (BGS) structure in The Dalles Dam (TDA) forebay on the Columbia River. The work was conducted by Pacific Northwest National Laboratory for the U.S. Army Corps of Engineers, Portland District (CENWP). The CFD results were an invaluable tool for the analysis, both from a Regional and Agency perspective (for the fish passage evaluation) and a CENWP perspective (supporting the BGS design and location). The new CFD model (TDA forebay model) included the latest bathymetry (surveyed in 1999) and a detailed representation of the engineered structures (spillway, powerhouse main, fish, and service units). The TDA forebay model was designed and developed in a way that future studies could easily modify or, to a large extent, reuse large portions of the existing mesh. This study resulted in these key findings: (1) The TDA forebay model matched well with field-measured velocity data. (2) The TDA forebay model matched observations made at the 1:80 general physical model of the TDA forebay. (3) During the course of this study, the methodology typically used by CENWP to contour topographic data was shown to be inaccurate when applied to widely-spaced transect data. Contouring methodologies need to be revisited--especially before such things as modifying the bathymetry in the 1:80 general physical model are undertaken. Future alignments can be evaluated with the model staying largely intact. The next round of analysis will need to address fish passage demands and navigation concerns. CFD models can be used to identify the most promising locations and to provide quantified metrics for biological, hydraulic, and navigation criteria. The most promising locations should then be further evaluated in the 1:80 general physical model.

  3. Evolutionary triplet models of structured RNA.

    PubMed

    Bradley, Robert K; Holmes, Ian

    2009-08-01

    The reconstruction and synthesis of ancestral RNAs is a feasible goal for paleogenetics. This will require new bioinformatics methods, including a robust statistical framework for reconstructing histories of substitutions, indels and structural changes. We describe a "transducer composition" algorithm for extending pairwise probabilistic models of RNA structural evolution to models of multiple sequences related by a phylogenetic tree. This algorithm draws on formal models of computational linguistics as well as the 1985 protosequence algorithm of David Sankoff. The output of the composition algorithm is a multiple-sequence stochastic context-free grammar. We describe dynamic programming algorithms, which are robust to null cycles and empty bifurcations, for parsing this grammar. Example applications include structural alignment of non-coding RNAs, propagation of structural information from an experimentally-characterized sequence to its homologs, and inference of the ancestral structure of a set of diverged RNAs. We implemented the above algorithms for a simple model of pairwise RNA structural evolution; in particular, the algorithms for maximum likelihood (ML) alignment of three known RNA structures and a known phylogeny and inference of the common ancestral structure. We compared this ML algorithm to a variety of related, but simpler, techniques, including ML alignment algorithms for simpler models that omitted various aspects of the full model and also a posterior-decoding alignment algorithm for one of the simpler models. In our tests, incorporation of basepair structure was the most important factor for accurate alignment inference; appropriate use of posterior-decoding was next; and fine details of the model were least important. Posterior-decoding heuristics can be substantially faster than exact phylogenetic inference, so this motivates the use of sum-over-pairs heuristics where possible (and approximate sum-over-pairs). For more exact probabilistic

  4. Modeling and structural analysis of honeycomb structure mirror

    NASA Astrophysics Data System (ADS)

    Li, Yeping

    2012-09-01

    In development of large-scale astronomical telescopes, some promising new technology and method such as honeycomb structure mirrors and silicon carbide mirrors are applied for primary mirrors. Especially in space telescopes, the mirror lightweight design is becoming the key technology and honeycomb structure mirrors are normally required more and more to reduce the cost and increase the feasibility of the telescopes system. In this paper, a parameter FEA model of a two meters honeycomb structure mirror has been built, by using the engineering analysis software ANSYS. Through this model, the structural analysis, thermal deformation analysis and the simulation active correction of low-order frequency aberration by the finite element method have been presented.

  5. The Adventure Model: A Replication Study To Determine if Different Adventure Skills Support the Model.

    ERIC Educational Resources Information Center

    Gilbertson, Ken; Ewert, Alan

    First developed and tested in 1989, the Adventure Model suggests that as adventure participants become more skilled and specialized, they experience predictable changes in several participation behaviors. While previous studies supported the model, they were carried out with college students having similar skill and motivational characteristics.…

  6. Developing a Physiologically-Based Pharmacokinetic Model Knowledgebase in Support of Provisional Model Construction - poster

    EPA Science Inventory

    Building new physiologically based pharmacokinetic (PBPK) models requires a lot data, such as the chemical-specific parameters and in vivo pharmacokinetic data. Previously-developed, well-parameterized, and thoroughly-vetted models can be great resource for supporting the constr...

  7. Social Support, Conflict, Major Life Stressors, and Adaptive Coping Strategies in Latino Middle School Students: An Integrative Model

    ERIC Educational Resources Information Center

    Crean, Hugh F.

    2004-01-01

    Structural equation modeling techniques were used to test a conceptual framework for improved understanding of the relationships involved in adolescent risk and protective factors. Specifically, the model examined the direct and indirect associations, via adaptive coping strategies, that acute life stressors and contextual support and conflict…

  8. A Model for the Electronic Support of Practice-Based Research Networks

    PubMed Central

    Peterson, Kevin A.; Delaney, Brendan C.; Arvanitis, Theodoros N.; Taweel, Adel; Sandberg, Elisabeth A.; Speedie, Stuart; Richard Hobbs, F. D.

    2012-01-01

    PURPOSE The principal goal of the electronic Primary Care Research Network (ePCRN) is to enable the development of an electronic infrastructure to support clinical research activities in primary care practice-based research networks (PBRNs). We describe the model that the ePCRN developed to enhance the growth and to expand the reach of PBRN research. METHODS Use cases and activity diagrams were developed from interviews with key informants from 11 PBRNs from the United States and United Kingdom. Discrete functions were identified and aggregated into logical components. Interaction diagrams were created, and an overall composite diagram was constructed describing the proposed software behavior. Software for each component was written and aggregated, and the resulting prototype application was pilot tested for feasibility. A practical model was then created by separating application activities into distinct software packages based on existing PBRN business rules, hardware requirements, network requirements, and security concerns. RESULTS We present an information architecture that provides for essential interactions, activities, data flows, and structural elements necessary for providing support for PBRN translational research activities. The model describes research information exchange between investigators and clusters of independent data sites supported by a contracted research director. The model was designed to support recruitment for clinical trials, collection of aggregated anonymous data, and retrieval of identifiable data from previously consented patients across hundreds of practices. CONCLUSIONS The proposed model advances our understanding of the fundamental roles and activities of PBRNs and defines the information exchange commonly used by PBRNs to successfully engage community health care clinicians in translational research activities. By describing the network architecture in a language familiar to that used by software developers, the model provides

  9. Structural modeling for multicell composite rotor blades

    NASA Technical Reports Server (NTRS)

    Rehfield, Lawrence W.; Atilgan, Ali R.

    1987-01-01

    Composite material systems are currently good candidates for aerospace structures, primarily for the design flexibility they offer, i.e., it is possible to tailor the material and manufacturing approach to the application. A working definition of elastic or structural tailoring is the use of structural concept, fiber orientation, ply stacking sequence, and a blend of materials to achieve specific performance goals. In the design process, choices of materials and dimensions are made which produce specific response characteristics, and which permit the selected goals to be achieved. Common choices for tailoring goals are preventing instabilities or vibration resonances or enhancing damage tolerance. An essential, enabling factor in the design of tailored composite structures is structural modeling that accurately, but simply, characterizes response. The objective of this paper is to present a new multicell beam model for composite rotor blades and to validate predictions based on the new model by comparison with a finite element simulation in three benchmark static load cases.

  10. Formal representation of 3D structural geological models

    NASA Astrophysics Data System (ADS)

    Wang, Zhangang; Qu, Honggang; Wu, Zixing; Yang, Hongjun; Du, Qunle

    2016-05-01

    The development and widespread application of geological modeling methods has increased demands for the integration and sharing services of three dimensional (3D) geological data. However, theoretical research in the field of geological information sciences is limited despite the widespread use of Geographic Information Systems (GIS) in geology. In particular, fundamental research on the formal representations and standardized spatial descriptions of 3D structural models is required. This is necessary for accurate understanding and further applications of geological data in 3D space. In this paper, we propose a formal representation method for 3D structural models using the theory of point set topology, which produces a mathematical definition for the major types of geological objects. The spatial relationships between geologic boundaries, structures, and units are explained in detail using the 9-intersection model. Reasonable conditions for describing the topological space of 3D structural models are also provided. The results from this study can be used as potential support for the standardized representation and spatial quality evaluation of 3D structural models, as well as for specific needs related to model-based management, query, and analysis.

  11. Integrating Cache Performance Modeling and Tuning Support in Parallelization Tools

    NASA Technical Reports Server (NTRS)

    Waheed, Abdul; Yan, Jerry; Saini, Subhash (Technical Monitor)

    1998-01-01

    With the resurgence of distributed shared memory (DSM) systems based on cache-coherent Non Uniform Memory Access (ccNUMA) architectures and increasing disparity between memory and processors speeds, data locality overheads are becoming the greatest bottlenecks in the way of realizing potential high performance of these systems. While parallelization tools and compilers facilitate the users in porting their sequential applications to a DSM system, a lot of time and effort is needed to tune the memory performance of these applications to achieve reasonable speedup. In this paper, we show that integrating cache performance modeling and tuning support within a parallelization environment can alleviate this problem. The Cache Performance Modeling and Prediction Tool (CPMP), employs trace-driven simulation techniques without the overhead of generating and managing detailed address traces. CPMP predicts the cache performance impact of source code level "what-if" modifications in a program to assist a user in the tuning process. CPMP is built on top of a customized version of the Computer Aided Parallelization Tools (CAPTools) environment. Finally, we demonstrate how CPMP can be applied to tune a real Computational Fluid Dynamics (CFD) application.

  12. Graduating to Postdoc: Information-Sharing in Support of Organizational Structures and Needs

    NASA Technical Reports Server (NTRS)

    Keller, Richard M.; Lucas, Paul J.; Compton, Michael M.; Stewart, Helen J.; Baya, Vinod; DelAlto, Martha

    1999-01-01

    The deployment of information-sharing systems in large organizations can significantly impact existing policies and procedures with regard to authority and control over information. Unless information-sharing systems explicitly support organizational structures and needs, these systems will be rejected summarily. The Postdoc system is a deployed Web-based information-sharing system created specifically to address organizational needs. Postdoc contains various organizational support features including a shared, globally navigable document space, as well as specialized access control, distributed administration, and mailing list features built around the key notion of hierarchical group structures. We review successes and difficulties in supporting organizational needs with Postdoc

  13. Theoretical models of possible compact nucleosome structures.

    PubMed

    Besker, Neva; Anselmi, Claudio; De Santis, Pasquale

    2005-04-01

    Chromatin structure seems related to the DNA linker length. This paper presents a systematic search of the possible chromatin structure as a function of the linker lengths, starting from three different low-resolution molecular models of the nucleosome. Gay-Berne potential was used to evaluate the relative nucleosome packing energy. Results suggest that linker DNAs, which bridges and orientate nucleosomes, affect both the geometry and the rigidity of the global chromatin structure. PMID:15752596

  14. Hierarchically triangular prism structured Co3O4: Self-supported fabrication and photocatalytic property

    EPA Science Inventory

    The formation of ammonium cobalt (II) phosphate was utilized to synthesize unprecedented 3D structures of Co3O4, triangular prisms and trunk-like structures, via a self-supported and organics-free method. The length of a triangular side of the prepared 3D triangular prisms is ~1...

  15. Maternal Structure and Autonomy Support in Conversations about the Past: Contributions to Children's Autobiographical Memory

    ERIC Educational Resources Information Center

    Cleveland, Emily Sutcliffe; Reese, Elaine

    2005-01-01

    The authors examined the contributions of maternal structure and autonomy support to children's collaborative and independent reminiscing. Fifty mother-child dyads discussed past experiences when the children were 40 and 65 months old. Children also discussed past events with an experimenter at each age. Maternal structure and autonomy support…

  16. Nanoscale structure of the BMP antagonist chordin supports cooperative BMP binding.

    PubMed

    Troilo, Helen; Zuk, Alexandra V; Tunnicliffe, Richard B; Wohl, Alexander P; Berry, Richard; Collins, Richard F; Jowitt, Thomas A; Sengle, Gerhard; Baldock, Clair

    2014-09-01

    Bone morphogenetic proteins (BMPs) orchestrate key cellular events, such as proliferation and differentiation, in development and homeostasis. Extracellular antagonists, such as chordin, are essential regulators of BMP signaling. Chordin binds to BMPs blocking interaction with receptors, and cleavage by tolloid proteinases is thought to relieve this inhibition. A model has been previously proposed where chordin adopts a horseshoe-like arrangement enabling BMP binding cooperatively by terminal domains (1). Here, we present the nanoscale structure of human chordin using electron microscopy, small angle X-ray scattering, and solution-based biophysical techniques, which together show that chordin indeed has a compact horseshoe-shaped structure. Chordin variants were used to map domain locations within the chordin molecule. The terminal BMP-binding domains protrude as prongs from the main body of the chordin structure, where they are well positioned to interact with the growth factor. The spacing provided by the chordin domains supports the principle of a cooperative BMP-binding arrangement that the original model implied in which growth factors bind to both an N- and C-terminal von Willebrand factor C domain of chordin. Using binding and bioactivity assays, we compared full-length chordin with two truncated chordin variants, such as those produced by partial tolloid cleavage. Cleavage of either terminal domain has little effect on the affinity of chordin for BMP-4 and BMP-7 but C-terminal cleavage increases the efficacy of chordin as a BMP-4 inhibitor. Together these data suggest that partial tolloid cleavage is insufficient to ablate BMP inhibition and the C-terminal chordin domains play an important role in BMP regulation. PMID:25157165

  17. Nanoscale structure of the BMP antagonist chordin supports cooperative BMP binding

    PubMed Central

    Troilo, Helen; Zuk, Alexandra V.; Tunnicliffe, Richard B.; Wohl, Alexander P.; Berry, Richard; Collins, Richard F.; Jowitt, Thomas A.; Sengle, Gerhard; Baldock, Clair

    2014-01-01

    Bone morphogenetic proteins (BMPs) orchestrate key cellular events, such as proliferation and differentiation, in development and homeostasis. Extracellular antagonists, such as chordin, are essential regulators of BMP signaling. Chordin binds to BMPs blocking interaction with receptors, and cleavage by tolloid proteinases is thought to relieve this inhibition. A model has been previously proposed where chordin adopts a horseshoe-like arrangement enabling BMP binding cooperatively by terminal domains (1). Here, we present the nanoscale structure of human chordin using electron microscopy, small angle X-ray scattering, and solution-based biophysical techniques, which together show that chordin indeed has a compact horseshoe-shaped structure. Chordin variants were used to map domain locations within the chordin molecule. The terminal BMP-binding domains protrude as prongs from the main body of the chordin structure, where they are well positioned to interact with the growth factor. The spacing provided by the chordin domains supports the principle of a cooperative BMP-binding arrangement that the original model implied in which growth factors bind to both an N- and C-terminal von Willebrand factor C domain of chordin. Using binding and bioactivity assays, we compared full-length chordin with two truncated chordin variants, such as those produced by partial tolloid cleavage. Cleavage of either terminal domain has little effect on the affinity of chordin for BMP-4 and BMP-7 but C-terminal cleavage increases the efficacy of chordin as a BMP-4 inhibitor. Together these data suggest that partial tolloid cleavage is insufficient to ablate BMP inhibition and the C-terminal chordin domains play an important role in BMP regulation. PMID:25157165

  18. Mediation from Multilevel to Structural Equation Modeling

    PubMed Central

    MacKinnon, David P.; Valente, Matthew J.

    2016-01-01

    Background/Aims The purpose of this article is to outline multilevel structural equation modeling (MSEM) for mediation analysis of longitudinal data. The introduction of mediating variables can improve experimental and nonexperimental studies of child growth in several ways as discussed throughout this article. Single-mediator individual-level and multilevel mediation models illustrate several current issues in the estimation of mediation with longitudinal data. The strengths of incorporating structural equation modeling (SEM) with multilevel mediation modeling are described. Summary and Key Messages Longitudinal mediation models are pervasive in many areas of research including child growth. Longitudinal mediation models are ideally modeled as repeated measurements clustered within individuals. Further, the combination of MSEM and SEM provides an ideal approach for several reasons, including the ability to assess effects at different levels of analysis, incorporation of measurement error and possible random effects that vary across individuals. PMID:25413658

  19. Support Vector Machines for Petrophysical Modelling and Lithoclassification

    NASA Astrophysics Data System (ADS)

    Al-Anazi, Ammal Fannoush Khalifah

    2011-12-01

    Given increasing challenges of oil and gas production from partially depleted conventional or unconventional reservoirs, reservoir characterization is a key element of the reservoir development workflow. Reservoir characterization impacts well placement, injection and production strategies, and field management. Reservoir characterization projects point and line data to a large three-dimensional volume. The relationship between variables, e.g. porosity and permeability, is often established by regression yet the complexities between measured variables often lead to poor correlation coefficients between the regressed variables. Recent advances in machine learning methods have provided attractive alternatives for constructing interpretation models of rock properties in heterogeneous reservoirs. Here, Support Vector Machines (SVMs), a class of a learning machine that is formulated to output regression models and classifiers of competitive generalization capability, has been explored to determine its capabilities for determining the relationship, both in regression and in classification, between reservoir rock properties. This thesis documents research on the capability of SVMs to model petrophysical and elastic properties in heterogeneous sandstone and carbonate reservoirs. Specifically, the capabilities of SVM regression and classification has been examined and compared to neural network-based methods, namely multilayered neural networks, radial basis function neural networks, general regression neural networks, probabilistic neural networks, and linear discriminant analysis. The petrophysical properties that have been evaluated include porosity, permeability, Poisson's ratio and Young's modulus. Statistical error analysis reveals that the SVM method yields comparable or superior predictions of petrophysical and elastic rock properties and classification of the lithology compared to neural networks. The SVM method also shows uniform prediction capability under the

  20. Hierarchical Bayesian model updating for structural identification

    NASA Astrophysics Data System (ADS)

    Behmanesh, Iman; Moaveni, Babak; Lombaert, Geert; Papadimitriou, Costas

    2015-12-01

    A new probabilistic finite element (FE) model updating technique based on Hierarchical Bayesian modeling is proposed for identification of civil structural systems under changing ambient/environmental conditions. The performance of the proposed technique is investigated for (1) uncertainty quantification of model updating parameters, and (2) probabilistic damage identification of the structural systems. Accurate estimation of the uncertainty in modeling parameters such as mass or stiffness is a challenging task. Several Bayesian model updating frameworks have been proposed in the literature that can successfully provide the "parameter estimation uncertainty" of model parameters with the assumption that there is no underlying inherent variability in the updating parameters. However, this assumption may not be valid for civil structures where structural mass and stiffness have inherent variability due to different sources of uncertainty such as changing ambient temperature, temperature gradient, wind speed, and traffic loads. Hierarchical Bayesian model updating is capable of predicting the overall uncertainty/variability of updating parameters by assuming time-variability of the underlying linear system. A general solution based on Gibbs Sampler is proposed to estimate the joint probability distributions of the updating parameters. The performance of the proposed Hierarchical approach is evaluated numerically for uncertainty quantification and damage identification of a 3-story shear building model. Effects of modeling errors and incomplete modal data are considered in the numerical study.

  1. Modeling the Subsurface Structure of Sunspots

    NASA Astrophysics Data System (ADS)

    Moradi, H.; Baldner, C.; Birch, A. C.; Braun, D. C.; Cameron, R. H.; Duvall, T. L.; Gizon, L.; Haber, D.; Hanasoge, S. M.; Hindman, B. W.; Jackiewicz, J.; Khomenko, E.; Komm, R.; Rajaguru, P.; Rempel, M.; Roth, M.; Schlichenmaier, R.; Schunker, H.; Spruit, H. C.; Strassmeier, K. G.; Thompson, M. J.; Zharkov, S.

    2010-11-01

    While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspots: the monolithic model and the cluster model. Local helioseismology is the only means by which we can investigate subphotospheric structure. However, as current linear inversion techniques do not yet allow helioseismology to probe the internal structure with sufficient confidence to distinguish between the monolith and cluster models, the development of physically realistic sunspot models are a priority for helioseismologists. This is because they are not only important indicators of the variety of physical effects that may influence helioseismic inferences in active regions, but they also enable detailed assessments of the validity of helioseismic interpretations through numerical forward modeling. In this article, we provide a critical review of the existing sunspot models and an overview of numerical methods employed to model wave propagation through model sunspots. We then carry out a helioseismic analysis of the sunspot in Active Region 9787 and address the serious inconsistencies uncovered by Gizon et al. (2009a, 2009). We find that this sunspot is most probably associated with a shallow, positive wave-speed perturbation (unlike the traditional two-layer model) and that travel-time measurements are consistent with a horizontal outflow in the surrounding moat.

  2. Concepts and analysis for precision segmented reflector and feed support structures

    NASA Technical Reports Server (NTRS)

    Miller, Richard K.; Thomson, Mark W.; Hedgepeth, John M.

    1990-01-01

    Several issues surrounding the design of a large (20-meter diameter) Precision Segmented Reflector are investigated. The concerns include development of a reflector support truss geometry that will permit deployment into the required doubly-curved shape without significant member strains. For deployable and erectable reflector support trusses, the reduction of structural redundancy was analyzed to achieve reduced weight and complexity for the designs. The stiffness and accuracy of such reduced member trusses, however, were found to be affected to a degree that is unexpected. The Precision Segmented Reflector designs were developed with performance requirements that represent the Reflector application. A novel deployable sunshade concept was developed, and a detailed parametric study of various feed support structural concepts was performed. The results of the detailed study reveal what may be the most desirable feed support structure geometry for Precision Segmented Reflector/Large Deployable Reflector applications.

  3. Direct and Indirect Effects of Parental Influence upon Adolescent Alcohol Use: A Structural Equation Modeling Analysis

    ERIC Educational Resources Information Center

    Kim, Young-Mi; Neff, James Alan

    2010-01-01

    A model incorporating the direct and indirect effects of parental monitoring on adolescent alcohol use was evaluated by applying structural equation modeling (SEM) techniques to data on 4,765 tenth-graders in the 2001 Monitoring the Future Study. Analyses indicated good fit of hypothesized measurement and structural models. Analyses supported both…

  4. Developing an Information Technology Support Model for Higher Education.

    ERIC Educational Resources Information Center

    Kesner, Richard M.

    1997-01-01

    Babson College (Massachusetts) responded to expanded campus computer use and resulting demand for support services by developing service delivery tailored to user groups' needs. Resources devoted to this effort have grown dramatically, and include help desk and dispatch support, program of technology specialists, evening support to residence…

  5. ASPEN PLUS modeling of the SRC-I Demonstration Plant. Task 19: modeling support activities report

    SciTech Connect

    Not Available

    1984-09-28

    The APCI version of ASPEN PLUS was maintained and enhanced in order to support the requirements of the simulation effort described in the earlier tasks. The support effort is conveniently divided into systems support and technical support in the areas of flowsheeting and thermophysical properties. Systems support required installation of the fourth release of ASPEN PLUS, installation of AspenTech's updates to correct program errors, and several general maintenance tasks unique to the APCI version of ASPEN PLUS. Technical support in the area of flowsheeting consisted of the organization of training courses, consultation in solving simulation problems, and identifying and resolving problems resulting from bugs in ASPEN PLUS. Thermodynamic technical support consisted of developing a few new models, implementing the coal-fluid thermophysical models into ASPEN PLUS, providing convenient access to the physical properties through INSERTs, and consultation to resolve simulation problems resulting from the nonideality of the properties. All software enhancements to ASPEN PLUS have been described and delivered so that APCI's version of the program may be duplicated and maintained at other sites. 16 references.

  6. Structural models for nickel electrode active mass

    NASA Technical Reports Server (NTRS)

    Cornilsen, B. C.; Karjala, P. J.; Loyselle, P. L.

    1988-01-01

    Raman spectroscopic data allow one to distinguish nickel electrode active mass, alpha and beta phase materials. Discharges active mass is not isostructural with beta-Ni(OH)2. This is contrary to the generally accepted model for the discharged beta phase of active mass. It is concluded that charged active mass displays a disordered and nonstoichiometric, nonclose packed structure of the R3 bar m, NiOOH structure type. Raman spectral data and X ray diffraction data are analyzed and shown to be consistent with this structural model.

  7. Structural models for nickel electrode active mass

    NASA Technical Reports Server (NTRS)

    Cornilsen, Bahne C.; Karjala, P. J.; Loyselle, P. L.

    1987-01-01

    Raman spectroscopic data allow one to distinguish nickel electrode active mass, alpha and beta phase materials. Discharges active mass is not isostructural with beta-Ni(OH)2. This is contrary to the generally accepted model for the discharged beta phase of active mass. It is concluded that charged active mass displays a disordered and nonstoichiometric, nonclose packed structure of the R3 bar m, NiOOH structure type. Raman spectral data and x ray diffraction data are analyzed and shown to be consistent with this structural model.

  8. Ectopic Lymphoid Structures Support Ongoing Production of Class-Switched Autoantibodies in Rheumatoid Synovium

    PubMed Central

    Manzo, Antonio; Kelly, Stephen; Blades, Mark C; Kirkham, Bruce; Spencer, Jo; Pitzalis, Costantino

    2009-01-01

    Background Follicular structures resembling germinal centres (GCs) that are characterized by follicular dendritic cell (FDC) networks have long been recognized in chronically inflamed tissues in autoimmune diseases, including the synovium of rheumatoid arthritis (RA). However, it is debated whether these ectopic structures promote autoimmunity and chronic inflammation driving the production of pathogenic autoantibodies. Anti-citrullinated protein/peptide antibodies (ACPA) are highly specific markers of RA, predict a poor prognosis, and have been suggested to be pathogenic. Therefore, the main study objectives were to determine whether ectopic lymphoid structures in RA synovium: (i) express activation-induced cytidine deaminase (AID), the enzyme required for somatic hypermutation and class-switch recombination (CSR) of Ig genes; (ii) support ongoing CSR and ACPA production; and (iii) remain functional in a RA/severe combined immunodeficiency (SCID) chimera model devoid of new immune cell influx into the synovium. Methods and Findings Using immunohistochemistry (IHC) and quantitative Taqman real-time PCR (QT-PCR) in synovial tissue from 55 patients with RA, we demonstrated that FDC+ structures invariably expressed AID with a distribution resembling secondary lymphoid organs. Further, AID+/CD21+ follicular structures were surrounded by ACPA+/CD138+ plasma cells, as demonstrated by immune reactivity to citrullinated fibrinogen. Moreover, we identified a novel subset of synovial AID+/CD20+ B cells outside GCs resembling interfollicular large B cells. In order to gain direct functional evidence that AID+ structures support CSR and in situ manufacturing of class-switched ACPA, 34 SCID mice were transplanted with RA synovium and humanely killed at 4 wk for harvesting of transplants and sera. Persistent expression of AID and Iγ-Cμ circular transcripts (identifying ongoing IgM-IgG class-switching) was observed in synovial grafts expressing FDCs/CD21L. Furthermore, synovial

  9. Fabrication of experimental three-meter space telescope primary and secondary mirror support structure

    NASA Technical Reports Server (NTRS)

    Mishler, H. W.

    1974-01-01

    The fabrication of prototype titanium alloy primary and secondary mirror support structures for a proposed experimental three-meter space telescope is discussed. The structure was fabricated entirely of Ti-6Al-4V tubing and plate. Fabrication included the development of procedures including welding, forming, and machining. Most of the structures was fabricated by gas-shielding tungsten-arc (GTA) welding with several major components fabricated by high frequency resistance (HFR) welding.

  10. Analysis and design of on-grade reinforced concrete track support structures

    NASA Technical Reports Server (NTRS)

    Mclean, F. G.; Williams, R. D.; Greening, L. R.

    1972-01-01

    For the improvement of rail service, the Department of Transportation, Federal Rail Administration, is sponsoring a test track on the Atchison, Topeka, and Santa Fe Railway. The test track will contain nine separate rail support structures, including one conventional section for control and three reinforced concrete structures on grade, one slab and two beam sections. The analysis and design of these latter structures was accomplished by means of the finite element method, NASTRAN, and is presented.

  11. Evaluation and Reduction of Machine Difference in Press Working with Utilization of Dedicated Die Support Structure and Numerical Methodologies

    NASA Astrophysics Data System (ADS)

    Ohashi, Takahiro

    2011-05-01

    In this study, support structures of a die for press working are discussed to solve the machine difference problems amongst presses. The developed multi-point die support structures are not only utilized for adjusting elastic deformation of a die, but also for in-process sensing of the behavior of a die. The structures have multiple support cells between a die and the slide of a press machine. The cell, known as `a support unit,' has the strain gauges attached on its side, and works in both ways as a kind of spring and a load and displacement sensor. The cell contacts on the die with a ball-contact, therefore it transmits only the vertical force at each support point. The isolation of a momentum and horizontal load at each support point contributes for a simple numerical model; it helps us to know the practical boundary condition at the points under an actual production. In addition, the momentum and horizontal forces at the points are useless for press working; the isolation of these forces contributes to reduce a jolt and related machine differences. The horizontal distribution of support units is changed to reduce elastic deformation of a die; it contributes to reduce a jolt, alignment errors of a die and geometrical errors of a product. The validity of those adjustments are confirmed with evaluating a product shape of a deep drawing and measuring jolts between upper and lower stamping dies. Furthermore, die deformation in a process is analyzed with using elastic FE analysis with actual bearing loads compiled from each support unit.

  12. A Brief Guide to Structural Equation Modeling

    ERIC Educational Resources Information Center

    Weston, Rebecca; Gore, Paul A., Jr.

    2006-01-01

    To complement recent articles in this journal on structural equation modeling (SEM) practice and principles by Martens and by Quintana and Maxwell, respectively, the authors offer a consumer's guide to SEM. Using an example derived from theory and research on vocational psychology, the authors outline six steps in SEM: model specification,…

  13. Causality, Confirmation, Credulity, and Structural Equation Modeling.

    ERIC Educational Resources Information Center

    Biddle, Bruce J.; Marlin, Marjorie M.

    1987-01-01

    Defines structural equation modeling (SEM) and points out its relation to other more familiar data-analytic techniques, as well as some of the potentials and pitfalls of SEM in the analysis of developmental data. Discussion focuses on causal modeling, path diagrams, ordinary least-squares regression analysis, and powerful methods for model…

  14. Improving knowledge management through the support of image examination and data annotation using DICOM structured reporting.

    PubMed

    Torres, José Salavert; Damian Segrelles Quilis, J; Espert, Ignacio Blanquer; García, Vicente Hernandez

    2012-12-01

    An important effort has been invested on improving the image diagnosis process in different medical areas using information technologies. The field of medical imaging involves two main data types: medical imaging and reports. Developments based on the DICOM standard have demonstrated to be a convenient and widespread solution among the medical community. The main objective of this work is to design a Web application prototype that will be able to improve diagnosis and follow-on of breast cancer patients. It is based on TRENCADIS middleware, which provides a knowledge-oriented storage model composed by federated repositories of DICOM image studies and DICOM-SR medical reports. The full structure and contents of the diagnosis reports are used as metadata for indexing images. The TRENCADIS infrastructure takes full advantage of Grid technologies by deploying multi-resource grid services that enable multiple views (reports schemes) of the knowledge database. The paper presents a real deployment of such Web application prototype in the Dr. Peset Hospital providing radiologists with a tool to create, store and search diagnostic reports based on breast cancer explorations (mammography, magnetic resonance, ultrasound, pre-surgery biopsy and post-surgery biopsy), improving support for diagnostics decisions. A technical details for use cases (outlining enhanced multi-resource grid services communication and processing steps) and interactions between actors and the deployed prototype are described. As a result, information is more structured, the logic is clearer, network messages have been reduced and, in general, the system is more resistant to failures. PMID:22841747

  15. Oxidation Reaction Induced Structural Changes in Sub-Nanometer Platinum Supported on Alumina

    DOE PAGESBeta

    DeBusk, Melanie Moses; Allard, Jr, Lawrence Frederick; Blom, Douglas Allen; Narula, Chaitanya Kumar

    2015-01-01

    Platinum supported on alumina is an essential component of emission treatment catalysts used in transportation. Theoretical, experimental, and mechanistic aspects of platinum particles supported on a variety of supports have been extensively studied; however, available experimental information on the behavior of single vs. sub-nanometer platinum is extremely limited. To bridge the knowledge gap between single supported platinum and well-formed supported platinum nanoparticles, we have carried out synthesis, characterization, and CO and NO oxidation studies of sub-nanometer platinum supported on α, θ, and γ-Al2O3 and monitored changes in structure upon exposure to CO and NO oxidation conditions. We find that sub-nanometermore » Pt is highly effective for CO oxidation due to high platinum dispersion but is not very efficient as NO oxidation catalyst. Furthermore, sub-nanometer platinum agglomerates rapidly under CO or NO oxidation conditions to form nanoparticles.« less

  16. Oxidation-induced structural changes in sub-nanometer platinum supported on alumina

    SciTech Connect

    DeBusk, Melanie Moses; Allard, Jr, Lawrence Frederick; Blom, Douglas Allen; Narula, Chaitanya Kumar

    2015-06-26

    Platinum supported on alumina is an essential component of emission treatment catalysts used in transportation. Theoretical, experimental, and mechanistic aspects of platinum particles supported on a variety of supports have been extensively studied; however, available experimental information on the behavior of single vs. sub-nanometer platinum is extremely limited. To bridge the knowledge gap between single supported platinum and well-formed supported platinum nanoparticles, we have carried out synthesis, characterization, and CO and NO oxidation studies of sub-nanometer platinum supported on α, θ, and γ-Al2O3 and monitored changes in structure upon exposure to CO and NO oxidation conditions. Furthermore, we find that sub-nanometer Pt is highly effective for CO oxidation due to high platinum dispersion but is not very efficient as NO oxidation catalyst. Lastly, sub-nanometer platinum agglomerates rapidly under CO or NO oxidation conditions to form nanoparticles.

  17. Oxidation-induced structural changes in sub-nanometer platinum supported on alumina

    DOE PAGESBeta

    DeBusk, Melanie Moses; Allard, Jr, Lawrence Frederick; Blom, Douglas Allen; Narula, Chaitanya Kumar

    2015-06-26

    Platinum supported on alumina is an essential component of emission treatment catalysts used in transportation. Theoretical, experimental, and mechanistic aspects of platinum particles supported on a variety of supports have been extensively studied; however, available experimental information on the behavior of single vs. sub-nanometer platinum is extremely limited. To bridge the knowledge gap between single supported platinum and well-formed supported platinum nanoparticles, we have carried out synthesis, characterization, and CO and NO oxidation studies of sub-nanometer platinum supported on α, θ, and γ-Al2O3 and monitored changes in structure upon exposure to CO and NO oxidation conditions. Furthermore, we find thatmore » sub-nanometer Pt is highly effective for CO oxidation due to high platinum dispersion but is not very efficient as NO oxidation catalyst. Lastly, sub-nanometer platinum agglomerates rapidly under CO or NO oxidation conditions to form nanoparticles.« less

  18. Emulating a flexible space structure: Modeling

    NASA Technical Reports Server (NTRS)

    Waites, H. B.; Rice, S. C.; Jones, V. L.

    1988-01-01

    Control Dynamics, in conjunction with Marshall Space Flight Center, has participated in the modeling and testing of Flexible Space Structures. Through the series of configurations tested and the many techniques used for collecting, analyzing, and modeling the data, many valuable insights have been gained and important lessons learned. This paper discusses the background of the Large Space Structure program, Control Dynamics' involvement in testing and modeling of the configurations (especially the Active Control Technique Evaluation for Spacecraft (ACES) configuration), the results from these two processes, and insights gained from this work.

  19. Solar structure: Models and inferences from helioseismology

    SciTech Connect

    Guzik, J.A.

    1998-12-31

    In this review the author summarizes results published during approximately the least three years concerning the state of one-dimensional solar interior modeling. She discusses the effects of refinements to the input physics, motivated by improving the agreement between calculated and observed solar oscillation frequencies, or between calculated and inferred solar structure. She has omitted two- and three-dimensional aspects of the solar structure, such as the rotation profile, detailed modeling of turbulent convection, and magnetic fields, although further progress in refining solar interior models may require including such two- and three-dimensional dynamical effects.

  20. Structured building model reduction toward parallel simulation

    SciTech Connect

    Dobbs, Justin R.; Hencey, Brondon M.

    2013-08-26

    Building energy model reduction exchanges accuracy for improved simulation speed by reducing the number of dynamical equations. Parallel computing aims to improve simulation times without loss of accuracy but is poorly utilized by contemporary simulators and is inherently limited by inter-processor communication. This paper bridges these disparate techniques to implement efficient parallel building thermal simulation. We begin with a survey of three structured reduction approaches that compares their performance to a leading unstructured method. We then use structured model reduction to find thermal clusters in the building energy model and allocate processing resources. Experimental results demonstrate faster simulation and low error without any interprocessor communication.

  1. Computational modeling of wall-supported dense Z-pinch

    SciTech Connect

    Sheehey, P.; Gerwin, R.A.; Kirkpatrick, R.

    1997-11-01

    In our previous computational modeling of deuterium-fiber-initiated Z-pinches intended for ohmic self-heating to fusion conditions, instability-driven expansion caused densities to drop far below those desired for fusion applications; such behavior has been observed on experiments such as Los Alamos` HDZP-II. A new application for deuterium-fiber-initiated Z-pinches is Magnetized Target Fusion (MTF), in which a preheated and magnetized target plasma is hydrodynamically compressed, by a separately driven liner, to fusion conditions. Although the conditions necessary for suitable target plasma--density O(10{sup 18} cm{sup -3}), temperature O(100 eV), magnetic field O(100 kG)--are less extreme than those required for the previous ohmically heated fusion scheme, the plasma must remain magnetically insulated and clean long enough to be compressed by the imploding liner to fusion conditions, e.g., several microseconds. A fiber-initiated Z-pinch in a 2-cm-radius, 2-cm long conducting liner has been built at Los Alamos to investigate its suitability as an MTF target plasma. Two-dimensional magnetohydrodynamic modeling of this experiment shows early instability similar to that seen on HDZP-II; however, when plasma finds support and stabilization at the outer radial wall, a relatively stable profile forms and persists. Comparison of experimental results and computations, and computational inclusion of additional experimental details is being done. Analytic and computational investigation is also being done on possible instability-driven cooling of the plasma by Benard-like convective cells adjacent to the cold wall.

  2. Finite-Element Modeling For Structural Analysis

    NASA Technical Reports Server (NTRS)

    Min, J. B.; Androlake, S. G.

    1995-01-01

    Report presents study of finite-element mathematical modeling as used in analyzing stresses and strains at joints between thin, shell-like components (e.g., ducts) and thicker components (e.g., flanges or engine blocks). First approach uses global/local model to evaluate system. Provides correct total response and correct representation of stresses away from any discontinuities. Second approach involves development of special transition finite elements to model transitions between shells and thicker structural components.

  3. Integrated developmental model of life-support capabilities in wheat

    NASA Technical Reports Server (NTRS)

    Darnell, R. L.; Obrien, C. O.

    1994-01-01

    The objective of this project was to develop a model for CO2, O2, H2O, and nitrogen use during the life cycle of wheat. Spreadsheets and accompanying graphs were developed to illustrate plant population reactions to environmental parameters established in the Controlled Ecological Life Support System (CELSS) program at Kennedy Space Center, Fl. The spreadsheets and graphs were produced using validated biomass production chamber (BPC) data from BWT931. Conditions of the BPC during the 83 day plant growth period were as follows: The BPC area is 27.8 m(exp 2), volume is 113 m(exp 3). Temperatures during the 83 day plant growth period ranged from 16.3 to 24.8 C during the light cycle (except for day 69, when the minimum and maximum temperatures were 7.7 C and 7.9 C, respectively) and 14.5 C and 23.6 C during the dark cycle (except for day 49, when the minimum and maximum temperatures were 11.1 C and 11.3 C, respectively). Relative humidity was 85 percent for the first seven days of plant growth, and 70 percent thereafter. The plant leaf canopy area was 10 m(exp 2). Presented is a list and explanation of each spreadsheet and accompanying graph(s), conditions under which the data were collected, and formulas used to obtain each result.

  4. Upper Mantle Seismic Structure Beneath Southern Africa: Constraints on the Buoyancy Supporting the African Superswell

    NASA Astrophysics Data System (ADS)

    Brandt, Martin B. C.; Grand, Stephen P.; Nyblade, Andrew A.; Dirks, Paul H. G. M.

    2012-04-01

    We present new one-dimensional SH-wave velocity models of the upper mantle beneath the Kalahari craton in southern Africa obtained from waveform inversion of regional seismograms from an Mw = 5.9 earthquake located near Lake Tanganyika recorded on broadband seismic stations deployed during the 1997-1999 Southern African Seismic Experiment. The velocity in the lithosphere beneath the Kalahari craton is similar to that of other shields, and there is little evidence for a significant low velocity zone beneath the lithosphere. The lower part of the lithosphere, from 110 to 220 km depth, is slightly slower than beneath other shields, possibly due to higher temperatures or a decrease in Mg number (Mg#). If the slower velocities are caused by a thermal anomaly, then slightly less than half of the unusually high elevation of the Kalahari craton can be explained by shallow buoyancy from a hot lithosphere. However, a decrease in the Mg# of the lower lithosphere would increase the density and counteract the buoyancy effect of the higher temperatures. We obtain a thickness of 250 ± 30 km for the mantle transition zone, which is similar to the global average, but the velocity gradient between the 410 and 660 km discontinuities is less steep than in global models, such as PREM and IASP91. We also obtain velocity jumps of between 0.16 ± 0.1 and 0.21 ± 0.1 km/s across the 410 km discontinuity. Our results suggest that there may be a thermal or chemical anomaly in the mantle transition zone, or alternatively that the shear wave velocity structure of the transition zone in global reference models needs to be refined. Overall, our seismic models provide little support for an upper mantle source of buoyancy for the unusually high elevation of the Kalahari craton, and hence the southern African portion of the African Superswell.

  5. Stochastic Time Models of Syllable Structure

    PubMed Central

    Shaw, Jason A.; Gafos, Adamantios I.

    2015-01-01

    Drawing on phonology research within the generative linguistics tradition, stochastic methods, and notions from complex systems, we develop a modelling paradigm linking phonological structure, expressed in terms of syllables, to speech movement data acquired with 3D electromagnetic articulography and X-ray microbeam methods. The essential variable in the models is syllable structure. When mapped to discrete coordination topologies, syllabic organization imposes systematic patterns of variability on the temporal dynamics of speech articulation. We simulated these dynamics under different syllabic parses and evaluated simulations against experimental data from Arabic and English, two languages claimed to parse similar strings of segments into different syllabic structures. Model simulations replicated several key experimental results, including the fallibility of past phonetic heuristics for syllable structure, and exposed the range of conditions under which such heuristics remain valid. More importantly, the modelling approach consistently diagnosed syllable structure proving resilient to multiple sources of variability in experimental data including measurement variability, speaker variability, and contextual variability. Prospects for extensions of our modelling paradigm to acoustic data are also discussed. PMID:25996153

  6. Linking Models and Data on Vegetation Structure

    NASA Astrophysics Data System (ADS)

    Hurtt, G. C.; Fisk, J.; Thomas, R.; Dubayah, R.; Moorcroft, P.; Shugart, H.

    2008-12-01

    Forested ecosystems consist of a dynamic mosaic of patches on the landscape at different stages of recovery from disturbances. Recent studies have addressed this heterogeneity by combining remotely sensed measurements of vegetation structure, and advanced ecological models that track the dynamics of vegetation structure, to produce accurate estimates of both carbon stocks and fluxes at a set of important study sites. Now future satellite missions such as DESDYNI hold the potential to provide key data on vegetation structure needed to reduce uncertainties in terrestrial carbon dynamics globally. Here, we developed and analyzed a set of models to quantify the effects of limited sampling and/or coarse resolution averaging of structure measurements on model predictions. Generally, both limited sampling and coarse resolution averaging caused model initialization error, and led to subsequent prediction uncertainty and error. In cases with representative sampling, sufficient resolution, and linear dynamics, errors in initialization tended to compensate at larger scales. However, with inadequate sampling, overly coarse resolution data, and non-linear dynamics, errors in initialization led to bias. This study provides a generalized framework for assessing the tradeoffs between the quantity and quality of data on vegetation structure, and the science from models which depend on it.

  7. Accountability, responsiveness and quality for clients model of home support: a model for improved home support services to promote aging at home.

    PubMed

    Kelly, Judy; Orr, Alison

    2009-01-01

    As the proportion of older adults increases within the Canadian population, healthcare systems across the country are facing increased demands for home-based services, including home care nursing, rehabilitation, case management, adult day programs, respite, meal programs and home support. Home support is one of the core care services required in the community to enable older adults to remain at home as long as possible. In 2006, Vancouver Community introduced a new home support delivery and performance management model: the Accountability, Responsiveness and Quality for Clients Model of Home Support (ARQ Model) (VCH 2006). The main components of the ARQ Model are an expanded use of "cluster care" along with stable monthly funding for high-density buildings and neighbourhoods; the introduction of specific monthly and quarterly quality performance reporting; and the implementation of performance-based funding for home support. This article discusses the setup of the ARQ model, its ongoing evaluation and results achieved thus far. PMID:20057219

  8. Structural Modelling of Two Dimensional Amorphous Materials

    NASA Astrophysics Data System (ADS)

    Kumar, Avishek

    The continuous random network (CRN) model of network glasses is widely accepted as a model for materials such as vitreous silica and amorphous silicon. Although it has been more than eighty years since the proposal of the CRN, there has not been conclusive experimental evidence of the structure of glasses and amorphous materials. This has now changed with the advent of two-dimensional amorphous materials. Now, not only the distribution of rings but the actual atomic ring structure can be imaged in real space, allowing for greater charicterization of these types of networks. This dissertation reports the first work done on the modelling of amorphous graphene and vitreous silica bilayers. Models of amorphous graphene have been created using a Monte Carlo bond-switching method and MD method. Vitreous silica bilayers have been constructed using models of amorphous graphene and the ring statistics of silica bilayers has been studied.

  9. Preliminary results of Physiological plant growth modelling for human life support in space

    NASA Astrophysics Data System (ADS)

    Sasidharan L, Swathy; Dussap, Claude-Gilles; Hezard, Pauline

    2012-07-01

    Human life support is fundamental and crucial in any kind of space explorations. MELiSSA project of European Space Agency aims at developing a closed, artificial ecological life support system involving human, plants and micro organisms. Consuming carbon dioxide and water from the life support system, plants grow in one of the chambers and convert it into food and oxygen along with potable water. The environmental conditions, nutrient availability and its consumption of plants should be studied and necessarily modeled to predict the amount of food, oxygen and water with respect to the environmental changes and limitations. The reliability of a completely closed system mainly depends on the control laws and strategies used. An efficient control can occur, only if the system to control is itself well known, described and ideally if the responses of the system to environmental changes are predictable. In this aspect, the general structure of plant growth model has been designed together with physiological modelling.The physiological model consists of metabolic models of leaves, stem and roots, of which concern specific metabolisms of the associated plant parts. On the basis of the carbon source transport (eg. sucrose) through stem, the metabolic models (leaf and root) can be interconnected to each other and finally coupled to obtain the entire plant model. For the first step, leaf metabolic model network was built using stoichiometric, mass and energy balanced metabolic equations under steady state approach considering all necessary plant pathways for growth and maintenance of leaves. As the experimental data for lettuce plants grown in closed and controlled environmental chambers were available, the leaf metabolic model has been established for lettuce leaves. The constructed metabolic network is analyzed using known stoichiometric metabolic technique called metabolic flux analysis (MFA). Though, the leaf metabolic model alone is not sufficient to achieve the

  10. Aeroelastic Model Structure Computation for Envelope Expansion

    NASA Technical Reports Server (NTRS)

    Kukreja, Sunil L.

    2007-01-01

    Structure detection is a procedure for selecting a subset of candidate terms, from a full model description, that best describes the observed output. This is a necessary procedure to compute an efficient system description which may afford greater insight into the functionality of the system or a simpler controller design. Structure computation as a tool for black-box modelling may be of critical importance in the development of robust, parsimonious models for the flight-test community. Moreover, this approach may lead to efficient strategies for rapid envelope expansion which may save significant development time and costs. In this study, a least absolute shrinkage and selection operator (LASSO) technique is investigated for computing efficient model descriptions of nonlinear aeroelastic systems. The LASSO minimises the residual sum of squares by the addition of an l(sub 1) penalty term on the parameter vector of the traditional 2 minimisation problem. Its use for structure detection is a natural extension of this constrained minimisation approach to pseudolinear regression problems which produces some model parameters that are exactly zero and, therefore, yields a parsimonious system description. Applicability of this technique for model structure computation for the F/A-18 Active Aeroelastic Wing using flight test data is shown for several flight conditions (Mach numbers) by identifying a parsimonious system description with a high percent fit for cross-validated data.

  11. Aeroelastic Model Structure Computation for Envelope Expansion

    NASA Technical Reports Server (NTRS)

    Kukreja, Sunil L.

    2007-01-01

    Structure detection is a procedure for selecting a subset of candidate terms, from a full model description, that best describes the observed output. This is a necessary procedure to compute an efficient system description which may afford greater insight into the functionality of the system or a simpler controller design. Structure computation as a tool for black-box modeling may be of critical importance in the development of robust, parsimonious models for the flight-test community. Moreover, this approach may lead to efficient strategies for rapid envelope expansion that may save significant development time and costs. In this study, a least absolute shrinkage and selection operator (LASSO) technique is investigated for computing efficient model descriptions of non-linear aeroelastic systems. The LASSO minimises the residual sum of squares with the addition of an l(Sub 1) penalty term on the parameter vector of the traditional l(sub 2) minimisation problem. Its use for structure detection is a natural extension of this constrained minimisation approach to pseudo-linear regression problems which produces some model parameters that are exactly zero and, therefore, yields a parsimonious system description. Applicability of this technique for model structure computation for the F/A-18 (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) Active Aeroelastic Wing project using flight test data is shown for several flight conditions (Mach numbers) by identifying a parsimonious system description with a high percent fit for cross-validated data.

  12. Modeling Fission Product Sorption in Graphite Structures

    SciTech Connect

    Szlufarska, Izabela; Morgan, Dane; Allen, Todd

    2013-04-08

    The goal of this project is to determine changes in adsorption and desorption of fission products to/from nuclear-grade graphite in response to a changing chemical environment. First, the project team will employ principle calculations and thermodynamic analysis to predict stability of fission products on graphite in the presence of structural defects commonly observed in very high- temperature reactor (VHTR) graphites. Desorption rates will be determined as a function of partial pressure of oxygen and iodine, relative humidity, and temperature. They will then carry out experimental characterization to determine the statistical distribution of structural features. This structural information will yield distributions of binding sites to be used as an input for a sorption model. Sorption isotherms calculated under this project will contribute to understanding of the physical bases of the source terms that are used in higher-level codes that model fission product transport and retention in graphite. The project will include the following tasks: Perform structural characterization of the VHTR graphite to determine crystallographic phases, defect structures and their distribution, volume fraction of coke, and amount of sp2 versus sp3 bonding. This information will be used as guidance for ab initio modeling and as input for sorptivity models; Perform ab initio calculations of binding energies to determine stability of fission products on the different sorption sites present in nuclear graphite microstructures. The project will use density functional theory (DFT) methods to calculate binding energies in vacuum and in oxidizing environments. The team will also calculate stability of iodine complexes with fission products on graphite sorption sites; Model graphite sorption isotherms to quantify concentration of fission products in graphite. The binding energies will be combined with a Langmuir isotherm statistical model to predict the sorbed concentration of fission

  13. Distributed parameter modeling of repeated truss structures

    NASA Technical Reports Server (NTRS)

    Wang, Han-Ching

    1994-01-01

    A new approach to find homogeneous models for beam-like repeated flexible structures is proposed which conceptually involves two steps. The first step involves the approximation of 3-D non-homogeneous model by a 1-D periodic beam model. The structure is modeled as a 3-D non-homogeneous continuum. The displacement field is approximated by Taylor series expansion. Then, the cross sectional mass and stiffness matrices are obtained by energy equivalence using their additive properties. Due to the repeated nature of the flexible bodies, the mass, and stiffness matrices are also periodic. This procedure is systematic and requires less dynamics detail. The first step involves the homogenization from a 1-D periodic beam model to a 1-D homogeneous beam model. The periodic beam model is homogenized into an equivalent homogeneous beam model using the additive property of compliance along the generic axis. The major departure from previous approaches in literature is using compliance instead of stiffness in homogenization. An obvious justification is that the stiffness is additive at each cross section but not along the generic axis. The homogenized model preserves many properties of the original periodic model.

  14. Surface generation and editing operations applied to structural support of aerospace vehicle fuselages. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Schwartz, Susan K.

    1992-01-01

    The Solid Modeling Aerospace Research Tool (SMART) is a computer aided design tool used in aerospace vehicle design. Modeling of structural components using SMART includes the representation of the transverse or cross-wise elements of a vehicle's fuselage, ringframes, and bulkheads. Ringframes are placed along a vehicle's fuselage to provide structural support and maintain the shape of the fuselage. Bulkheads are also used to maintain shape, but are placed at locations where substantial structural support is required. Given a Bezier curve representation of a cross sectional cut through a vehicle's fuselage and/or an internal tank, this project produces a first-guess Bezier patch representation of a ringframe or bulkhead at the cross-sectional position. The grid produced is later used in the structural analysis of the vehicle. The graphical display of the generated patches allows the user to edit patch control points in real time. Constraints considered in the patch generation include maintaining 'square-like' patches and placement of longitudinal, or lengthwise along the fuselage, structural elements called longerons.

  15. An Organizational Model for Instructional Support at a Community College.

    ERIC Educational Resources Information Center

    Mundell, Jacqueline; Celene-Martel, Coryl; Braziunas, Tom

    2003-01-01

    Describes the Instructional and Information Support Services (IISS) division at North Seattle Community College, which brings together the college's library, media services, and distance learning units as well as the Teaching and Learning center to support instruction campus-wide. Discusses the campus technological infrastructure, online courses,…

  16. Cause and Event: Supporting Causal Claims through Logistic Models

    ERIC Educational Resources Information Center

    O'Connell, Ann A.; Gray, DeLeon L.

    2011-01-01

    Efforts to identify and support credible causal claims have received intense interest in the research community, particularly over the past few decades. In this paper, we focus on the use of statistical procedures designed to support causal claims for a treatment or intervention when the response variable of interest is dichotomous. We identify…

  17. Dynamic and Structural Gas Turbine Engine Modeling

    NASA Technical Reports Server (NTRS)

    Turso, James A.

    2003-01-01

    Model the interactions between the structural dynamics and the performance dynamics of a gas turbine engine. Generally these two aspects are considered separate, unrelated phenomena and are studied independently. For diagnostic purposes, it is desirable to bring together as much information as possible, and that involves understanding how performance is affected by structural dynamics (if it is) and vice versa. This can involve the relationship between thrust response and the excitation of structural modes, for instance. The job will involve investigating and characterizing these dynamical relationships, generating a model that incorporates them, and suggesting and/or developing diagnostic and prognostic techniques that can be incorporated in a data fusion system. If no coupling is found, at the least a vibration model should be generated that can be used for diagnostics and prognostics related to blade loss, for instance.

  18. Forebay Computational Fluid Dynamics Modeling for The Dalles Dam to Support Vortex Suppress Device Studies

    SciTech Connect

    Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.

    2006-12-01

    A computational fluid dynamics (CFD) model was used in an investigation into the suppression of a surface vortex that forms and the south-most spilling bay at The Dalles Project. The CFD work complemented work at the prototype and the reduced-scale physical models. The CFD model was based on a model developed for other work in the forebay but had additional resolution added near the spillway. Vortex suppression devices (VSDs) were to placed between pier noses and/or in the bulkhead slot of the spillway bays. The simulations in this study showed that placing VSD structures or a combination of structures to suppress the vortex would still result in near-surface flows to be entrained in a vortex near the downstream spillwall. These results were supported by physical model and prototype studies. However, there was a consensus of the fish biologists at the physical model that the fish would most likely move north and if the fish went under the VSD it would immediately exit the forebay through the tainter gate and not get trapped between VSDs or the VSDs and the tainter gate if the VSDs were deep enough.

  19. Sensitivity of actively damped structures to imperfections and modeling errors

    NASA Technical Reports Server (NTRS)

    Haftka, Raphael T.; Kapania, Rakesh K.

    1989-01-01

    The sensitivity of actively damped response of structures with respect to errors in the structural modeling is studied. Two ways of representing errors are considered. The first approach assumes errors in the form of spatial variations (or imperfections) in the assumed mass and stiffness properties of the structures. The second approach assumes errors due to such factors as unknown joint stiffnesses, discretization errors, and nonlinearities. These errors are represented here as discrepancies between experimental and analytical mode shapes and frequencies. The actively damped system considered here is a direct-rate feedback regulator based on a number of colocated velocity sensors and force actuators. The response of the controlled structure is characterized by the eigenvalues of the closed-loop system. The effects of the modeling errors are thus presented as the sensitivity of the eigenvalues of the closed-loop system. Results are presented for two examples: (1) a three-span simply supported beam controlled by three sensors and actuators, and (2) a laboratory structure consisting of a cruciform beam supported by cables.

  20. Model Comparison of Nonlinear Structural Equation Models with Fixed Covariates.

    ERIC Educational Resources Information Center

    Lee, Sik-Yum; Song, Xin-Yuan

    2003-01-01

    Proposed a new nonlinear structural equation model with fixed covariates to deal with some complicated substantive theory and developed a Bayesian path sampling procedure for model comparison. Illustrated the approach with an illustrative example using data from an international study. (SLD)

  1. Effects of particle size and edge structure on the electronic structure, spectroscopic features, and chemical properties of Au(111)-supported MoS2 nanoparticles.

    PubMed

    Bruix, Albert; Lauritsen, Jeppe V; Hammer, Bjørk

    2016-07-01

    Materials based on MoS2 are widely used as catalysts and their structure usually consists of single-layered MoS2 nanoparticles whose edges are known to constitute the catalytically active sites. Methods based on density functional theory are used in this work to calculate the electronic structure of representative computational models of MoS2 nanoparticles supported on Au(111). By considering nanoparticles with different edge-terminations, compositions, and sizes, we describe how the electronic structure, Mo3d core-level shifts, and chemical properties (i.e. H adsorption and S vacancy formation) depend on the MoS2 nanoparticle size and structure. In addition, site-specific properties, largely inaccessible when using only slab models of MoS2 edges, are reported, which reveal that the edge sites are not uniform along the nanoparticle and largely depend on the proximity to the corners of the triangular NPs, especially when interacting with a metallic support. Furthermore, a structural motif where H atoms adsorb favourably in a bridging position between two Mo atoms is proposed as an active site for the hydrogen evolution reaction. PMID:27076269

  2. Support Effects on Electronic Behaviors of Gold Nanoparticles Studied by X-Ray Absorption Fine Structure

    SciTech Connect

    Li Zhongrui; Yan Wensheng; Wei Shiqiang

    2007-02-02

    The electronic properties of gold nanoparticles supported on different supports were studied with X-ray absorption fine structure (XAFS). It was found that the tunability of the d-electron distribution in the nano-sized Au clusters can be realized by selective supporting. The Au atoms in the clusters gain 5d electrons when supported on SiO2, and lose 5d electrons when loaded over MgO, Al2O3, and TiO2. Contractions in bond lengths of between 0.5 and 1.6% from bulk metal values were observed from EXAFS data. This work demonstrates that the important role of the different supports in the 5d-charge distribution of Au nanoparticles and usefulness of XAFS in probing the electronic behavior of noble metal nanoparticles.

  3. Model reduction results for flexible space structures

    NASA Technical Reports Server (NTRS)

    Williams, Trevor; Mostarshedi, Masoud

    1993-01-01

    This paper describes the novel subsystem balancing technique for obtaining reduced-order models of flexible structures, and investigates its properties fully. This method can be regarded as a combination of the best features of modal truncation (efficiency) and internal balancing (accuracy); it is particularly well suited to the typical practical case of structures which possess clusters of close modes. Numerical results are then presented demonstrating the results obtained by applying subsystem balancing to the Air Force Phillips Laboratory ASTREX testbed, the Jet Propulsion Laboratory antenna facility, and the NASA Marshall Space Flight Center ACES structure.

  4. Local, global and electronic structure of supported gold nanoclusters determined by EXAFS, XRD and XPS methods

    NASA Astrophysics Data System (ADS)

    Aldea, Nicolae; Rednic, Vasile; Pintea, Stelian; Marginean, Petru; Barz, Bogdan; Gluhoi, Andreea; Nieuwenhuys, Bernard E.; Neumann, Manfred; Yaning, Xie; Matei, Florica

    2009-07-01

    We analyze gold nanoclusters as supported catalysts by extended X-ray absorption fine structure, X-ray diffraction and X-ray photoelectron spectroscopy in order to determine their local, global and electronic structure. The present study points out a strong deformation of the local structure of the metal due to its interaction with oxide supports. We determine the particle size distribution and microstrain functions of the Au nanoclusters by X-ray diffraction method. Based on X-ray absorption fine structure spectroscopy analysis we show that the entire local structure of the investigated systems is strongly distorted regarding the average Au-Au coordination number. The distances between atoms are practically the same as standard Au foil. The strong metal-support interaction is confirmed by the change in shape of the electron transition probability densities that appear in the Au L III-edge. From XPS investigations we find electronic states corresponding to gold as well as to the oxide supports.

  5. Material modeling and structural analysis with the microplane constitutive model

    NASA Astrophysics Data System (ADS)

    Brocca, Michele

    The microplane model is a versatile and powerful approach to constitutive modeling in which the stress-strain relations are defined in terms of vectors rather than tensors on planes of all possible orientations. Such planes are called the microplanes and are representative of the microstructure of the material. The microplane model with kinematic constraint has been successfully employed in the past in the modeling of concrete, soils, ice, rocks, fiber composites and other quasibrittle materials. The microplane model provides a powerful and efficient numerical and theoretical framework for the development and implementation of constitutive models for any kind of material. The dissertation presents a review of the background from which the microplane model stems, highlighting differences and similarities with other approaches. The basic structure of the microplane model is then presented, together with its extension to finite strain deformation. To show the effectiveness of the microplane model approach, some examples are given demonstrating applications of microplane models in structural analysis with the finite element method. Some new constitutive models are also introduced for materials characterized by very different properties and microstructures, showing that the approach is indeed very versatile and provides a robust basis for the study of a broad range of problems. New models are introduced for metal plasticity, shape memory alloys and cellular materials. The new models are compared quantitatively with the existing models and experimental data. In particular, the newly introduced microplane models for metal plasticity are compared with the classical J2-flow theory for incremental plasticity. An existing microplane model for concrete is employed in finite element analysis of the 'tube-squash' test, in which concrete undergoes very large deviatoric deformation, and of the size effect in compressive failure of concrete columns. The microplane model for shape

  6. Statistical modeling support for calibration of a multiphysics model of subcooled boiling flows

    SciTech Connect

    Bui, A. V.; Dinh, N. T.; Nourgaliev, R. R.; Williams, B. J.

    2013-07-01

    Nuclear reactor system analyses rely on multiple complex models which describe the physics of reactor neutronics, thermal hydraulics, structural mechanics, coolant physico-chemistry, etc. Such coupled multiphysics models require extensive calibration and validation before they can be used in practical system safety study and/or design/technology optimization. This paper presents an application of statistical modeling and Bayesian inference in calibrating an example multiphysics model of subcooled boiling flows which is widely used in reactor thermal hydraulic analysis. The presence of complex coupling of physics in such a model together with the large number of model inputs, parameters and multidimensional outputs poses significant challenge to the model calibration method. However, the method proposed in this work is shown to be able to overcome these difficulties while allowing data (observation) uncertainty and model inadequacy to be taken into consideration. (authors)

  7. Structural models for non-helical DNA.

    PubMed Central

    Yagil, G; Sussman, J L

    1986-01-01

    Structural modelling techniques are employed to explore the energetic requirements for the transformation of classical B DNA into unwound yet double-stranded DNA structures. Structural idealization using CORELS computer program of Sussman et al. followed by energy minimization using the EREF program of Levitt, leads to two regular non-helical models. In both models, the bases are conventionally paired and stacked, yet there is no net rotation between successive base pairs. One model, N1, has a 1-bp repeating unit; the second, N2, has a 2-bp repeating unit. The dihedral angles of the backbone all have values found either in the B or the Z form of DNA, except for the P-O5'-C5'-C4' angle, which is in the unprecedented g+ or g- domains. The energy difference found between the two N form models and B form DNA are 6.6 and 3.4 kcal/mol/nucleotide for N1 and N2 respectively. These relatively low energy differences encourage the idea that non-helical forms of DNA may contribute to the alternate DNA structures found in S1 nuclease sensitive and other regulatory regions of active genes. PMID:3017709

  8. A structural model for metallic glasses

    NASA Astrophysics Data System (ADS)

    Miracle, Daniel B.

    2004-10-01

    Despite the intense interest in metallic glasses for a variety of engineering applications, many details of their structure remain a mystery. Here, we present the first compelling atomic structural model for metallic glasses. This structural model is based on a new sphere-packing scheme-the dense packing of atomic clusters. Random positioning of solvent atoms and medium-range atomic order of solute atoms are combined to reproduce diffraction data successfully over radial distances up to ~1 nm. Although metallic glasses can have any number of chemically distinct solute species, this model shows that they contain no more than three topologically distinct solutes and that these solutes have specific and predictable sizes relative to the solvent atoms. Finally, this model includes defects that provide richness to the structural description of metallic glasses. The model accurately predicts the number of solute atoms in the first coordination shell of a typical solvent atom, and provides a remarkable ability to predict metallic-glass compositions accurately for a wide range of simple and complex alloys.

  9. Preserving Structure in Model-Free Tracking.

    PubMed

    Zhang, Lu; van der Maaten, Laurens J P

    2014-04-01

    Model-free trackers can track arbitrary objects based on a single (bounding-box) annotation of the object. Whilst the performance of model-free trackers has recently improved significantly, simultaneously tracking multiple objects with similar appearance remains very hard. In this paper, we propose a new multi-object model-free tracker (using a tracking-by-detection framework) that resolves this problem by incorporating spatial constraints between the objects. The spatial constraints are learned along with the object detectors using an online structured SVM algorithm. The experimental evaluation of our structure-preserving object tracker (SPOT) reveals substantial performance improvements in multi-object tracking. We also show that SPOT can improve the performance of single-object trackers by simultaneously tracking different parts of the object. Moreover, we show that SPOT can be used to adapt generic, model-based object detectors during tracking to tailor them towards a specific instance of that object. PMID:26353198

  10. Structure Model Analysis of the Kashima 34m Telescope

    NASA Astrophysics Data System (ADS)

    Nakajima, Junichi; Nakamura, Toshio; Saita, Takeshi; Horiguchi, Junji; Yuge, Kouhei

    2001-03-01

    Deformation analysis of the Kashima 34-m radio telescope is performed. Although the telescope has a large aperture and accurate reflector panels, the dish support structures determine the high-frequency performance. Especially in millimeter wavelength, deformations above 1-mm affect the telescope efficiency seriously. We have modeled 34-m telescopes into elements and used a finite element method FEM to simulate accurate telescope deformations. The first results we obtained agreed well with the realistic deformation. Future analysis and telescope evaluations based on computer simulations are possible with this FEM model.

  11. Structure development models of ETS-VI

    NASA Astrophysics Data System (ADS)

    Katagi, Tsuguhiko; Tsujihata, Akio; Nishio, Masanobu; Kuwao, Fumihiro; Tsukashima, Takashi; Katoh, Tatsuo; Akaeda, Tadayoshi

    Japan's Engineering Test Satellite (ETS) VI has been designed to conduct several communications experiments relevant to future direct-broadcasting satellites and is currently in its design finalization phase. Two structure-development models have accordingly been devised for static and dynamic loading tests, respectively. Results are presented from the ETS VI development models' modal survey, acoustics, sinusoid vibration, pyrotechnic shock, alignment, and mass properties tests.

  12. Au and Pt nanoparticle supported catalysts tailored for H-2 production: From models to powder catalysts

    DOE PAGESBeta

    T. D. Nguyen-Phan; Baber, A. E.; Rodriguez, J. A.; Senanayake, S. D.

    2015-12-10

    The use of metal nanoparticles (NPs), including Au and Pt, supported over oxides has been pivotal, and is ever increasing in enabling catalytic reactions which target the production of hydrogen. We review here the most recent works pertaining to the fundamental understanding of the structure, morphology, growth, characterization, and intrinsic phenomenological properties of Au– and Pt– based catalysts that influence the reactivity and selectivity to target hydrogen production. We draw on surface science and theoretical methods of model and powder catalysts using high resolution imaging, spectroscopy, scattering experiments, and theoretical studies. Based on these insights we identify key aspects ofmore » studies of supported metal nanoparticle (NP) catalysts for several reactions. The main focus of this review is on the intersection of catalytic chemistry related to the water-gas shift (WGS), oxygenate steam reforming (OSR), and solarassisted reactions (SAR).« less

  13. Au and Pt nanoparticle supported catalysts tailored for H-2 production: From models to powder catalysts

    SciTech Connect

    T. D. Nguyen-Phan; Baber, A. E.; Rodriguez, J. A.; Senanayake, S. D.

    2015-12-10

    The use of metal nanoparticles (NPs), including Au and Pt, supported over oxides has been pivotal, and is ever increasing in enabling catalytic reactions which target the production of hydrogen. We review here the most recent works pertaining to the fundamental understanding of the structure, morphology, growth, characterization, and intrinsic phenomenological properties of Au– and Pt– based catalysts that influence the reactivity and selectivity to target hydrogen production. We draw on surface science and theoretical methods of model and powder catalysts using high resolution imaging, spectroscopy, scattering experiments, and theoretical studies. Based on these insights we identify key aspects of studies of supported metal nanoparticle (NP) catalysts for several reactions. The main focus of this review is on the intersection of catalytic chemistry related to the water-gas shift (WGS), oxygenate steam reforming (OSR), and solarassisted reactions (SAR).

  14. High-Temperature Superconductors as Electromagnetic Deployment and Support Structures in Spacecraft. [NASA NIAC Phase I

    NASA Technical Reports Server (NTRS)

    Getliffe, Gwendolyn V.; Inamdar, Niraj K.; Masterson, Rebecca; Miller, David W.

    2012-01-01

    This report, concluding a one-year NIAC Phase I study, describes a new structural and mechanical technique aimed at reducing the mass and increasing the deployed-to-stowed length and volume ratios of spacecraft systems. This technique uses the magnetic fields generated by electrical current passing through coils of high-temperature superconductors (HTSs) to support spacecraft structures and deploy them to operational configurations from their stowed positions inside a launch vehicle fairing.

  15. Photoreceptor Cells With Profound Structural Deficits Can Support Useful Vision in Mice

    PubMed Central

    Thompson, Stewart; Blodi, Frederick R.; Lee, Swan; Welder, Chris R.; Mullins, Robert F.; Tucker, Budd A.; Stasheff, Steven F.; Stone, Edwin M.

    2014-01-01

    Purpose. In animal models of degenerative photoreceptor disease, there has been some success in restoring photoreception by transplanting stem cell–derived photoreceptor cells into the subretinal space. However, only a small proportion of transplanted cells develop extended outer segments, considered critical for photoreceptor cell function. The purpose of this study was to determine whether photoreceptor cells that lack a fully formed outer segment could usefully contribute to vision. Methods. Retinal and visual function was tested in wild-type and Rds mice at 90 days of age (RdsP90). Photoreceptor cells of mice homozygous for the Rds mutation in peripherin 2 never develop a fully formed outer segment. The electroretinogram and multielectrode recording of retinal ganglion cells were used to test retinal responses to light. Three distinct visual behaviors were used to assess visual capabilities: the optokinetic tracking response, the discrimination-based visual water task, and a measure of the effect of vision on wheel running. Results. RdsP90 mice had reduced but measurable electroretinogram responses to light, and exhibited light-evoked responses in multiple types of retinal ganglion cells, the output neurons of the retina. In optokinetic and discrimination-based tests, acuity was measurable but reduced, most notably when contrast was decreased. The wheel running test showed that RdsP90 mice needed 3 log units brighter luminance than wild type to support useful vision (10 cd/m2). Conclusions. Photoreceptors that lack fully formed outer segments can support useful vision. This challenges the idea that normal cellular structure needs to be completely reproduced for transplanted cells to contribute to useful vision. PMID:24569582

  16. Integrated Modelling Frameworks for Environmental Assessment and Decision Support

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Modern management of environmental resources defines problems from a holistic and integrated perspective, imposing strong requirements to Environmental Decision Support Systems (EDSSs) and Integrated Assessment Tools (IATs), which tend to be increasingly complex in terms of software architecture and...

  17. Modeling of variable speed refrigerated display cabinets based on adaptive support vector machine

    NASA Astrophysics Data System (ADS)

    Cao, Zhikun; Han, Hua; Gu, Bo

    2010-01-01

    In this paper the adaptive support vector machine (ASVM) method is introduced to the field of intelligent modeling of refrigerated display cabinets and used to construct a highly precise mathematical model of their performance. A model for a variable speed open vertical display cabinet was constructed using preprocessing techniques for measured data, including the elimination of outlying data points by the use of an exponential weighted moving average (EWMA). Using dynamic loss coefficient adjustment, the adaptation of the SVM for use in this application was achieved. From there, the object function for energy use per unit of display area total energy consumption (TEC)/total display area (TDA) was constructed and solved using the ASVM method. When compared to the results achieved using a back-propagation neural network (BPNN) model, the ASVM model for the refrigerated display cabinet was characterized by its simple structure, fast convergence speed and high prediction accuracy. The ASVM model also has better noise rejection properties than that of original SVM model. It was revealed by the theoretical analysis and experimental results presented in this paper that it is feasible to model of the display cabinet built using the ASVM method.

  18. The Effects of the Coordination Support on Shared Mental Models and Coordinated Action

    ERIC Educational Resources Information Center

    Kim, Hyunsong; Kim, Dongsik

    2008-01-01

    The purpose of this study was to examine the effects of coordination support (tool support and tutor support) on the development of shared mental models (SMMs) and coordinated action in a computer-supported collaborative learning environment. Eighteen students were randomly assigned to one of three conditions, including the tool condition, the…

  19. Data Model for Multi Hazard Risk Assessment Spatial Support Decision System

    NASA Astrophysics Data System (ADS)

    Andrejchenko, Vera; Bakker, Wim; van Westen, Cees

    2014-05-01

    The goal of the CHANGES Spatial Decision Support System is to support end-users in making decisions related to risk reduction measures for areas at risk from multiple hydro-meteorological hazards. The crucial parts in the design of the system are the user requirements, the data model, the data storage and management, and the relationships between the objects in the system. The implementation of the data model is carried out entirely with an open source database management system with a spatial extension. The web application is implemented using open source geospatial technologies with PostGIS as the database, Python for scripting, and Geoserver and javascript libraries for visualization and the client-side user-interface. The model can handle information from different study areas (currently, study areas from France, Romania, Italia and Poland are considered). Furthermore, the data model handles information about administrative units, projects accessible by different types of users, user-defined hazard types (floods, snow avalanches, debris flows, etc.), hazard intensity maps of different return periods, spatial probability maps, elements at risk maps (buildings, land parcels, linear features etc.), economic and population vulnerability information dependent on the hazard type and the type of the element at risk, in the form of vulnerability curves. The system has an inbuilt database of vulnerability curves, but users can also add their own ones. Included in the model is the management of a combination of different scenarios (e.g. related to climate change, land use change or population change) and alternatives (possible risk-reduction measures), as well as data-structures for saving the calculated economic or population loss or exposure per element at risk, aggregation of the loss and exposure using the administrative unit maps, and finally, producing the risk maps. The risk data can be used for cost-benefit analysis (CBA) and multi-criteria evaluation (SMCE). The

  20. Feature extraction for structural dynamics model validation

    SciTech Connect

    Hemez, Francois; Farrar, Charles; Park, Gyuhae; Nishio, Mayuko; Worden, Keith; Takeda, Nobuo

    2010-11-08

    This study focuses on defining and comparing response features that can be used for structural dynamics model validation studies. Features extracted from dynamic responses obtained analytically or experimentally, such as basic signal statistics, frequency spectra, and estimated time-series models, can be used to compare characteristics of structural system dynamics. By comparing those response features extracted from experimental data and numerical outputs, validation and uncertainty quantification of numerical model containing uncertain parameters can be realized. In this study, the applicability of some response features to model validation is first discussed using measured data from a simple test-bed structure and the associated numerical simulations of these experiments. issues that must be considered were sensitivity, dimensionality, type of response, and presence or absence of measurement noise in the response. Furthermore, we illustrate a comparison method of multivariate feature vectors for statistical model validation. Results show that the outlier detection technique using the Mahalanobis distance metric can be used as an effective and quantifiable technique for selecting appropriate model parameters. However, in this process, one must not only consider the sensitivity of the features being used, but also correlation of the parameters being compared.