MER : from landing to six wheels on Mars ... twice

NASA Technical Reports Server (NTRS)

Krajewski, Joel; Burke, Kevin; Lewicki, Chris; Limonadi, Daniel; Trebi-Ollennu, Ashitey; Voorhees, Chris

2005-01-01

Application of the Pathfinder landing system design to enclose the much larger Mars Exploration Rover required a variety of Rover deployments to achieve the surface driving configuration. The project schedule demanded that software design, engineering model test, and flight hardware build to be accomplished in parallel. This challenge was met through (a) bounding unknown environments against which to design and test, (b) early mechanical prototype testing, (c) constraining the scope of on-board autonomy to survival-critical deployments, (d) executing a balance of nominal and off-nominal test cases, (e) developing off-nominal event mitigation techniques before landing, (f) flexible replanning in response to surprises during operations. Here is discussed several specific events encountered during initial MER surface operations.

A comparative robustness evaluation of feedforward neurofilters

NASA Technical Reports Server (NTRS)

Troudet, Terry; Merrill, Walter

1993-01-01

A comparative performance and robustness analysis is provided for feedforward neurofilters trained with back propagation to filter additive white noise. The signals used in this analysis are simulated pitch rate responses to typical pilot command inputs for a modern fighter aircraft model. Various configurations of nonlinear and linear neurofilters are trained to estimate exact signal values from input sequences of noisy sampled signal values. In this application, nonlinear neurofiltering is found to be more efficient than linear neurofiltering in removing the noise from responses of the nominal vehicle model, whereas linear neurofiltering is found to be more robust in the presence of changes in the vehicle dynamics. The possibility of enhancing neurofiltering through hybrid architectures based on linear and nonlinear neuroprocessing is therefore suggested as a way of taking advantage of the robustness of linear neurofiltering, while maintaining the nominal performance advantage of nonlinear neurofiltering.

An Odds Ratio Approach for Detecting DDF under the Nested Logit Modeling Framework

ERIC Educational Resources Information Center

Terzi, Ragip; Suh, Youngsuk

2015-01-01

An odds ratio approach (ORA) under the framework of a nested logit model was proposed for evaluating differential distractor functioning (DDF) in multiple-choice items and was compared with an existing ORA developed under the nominal response model. The performances of the two ORAs for detecting DDF were investigated through an extensive…

Who really pays for health insurance? The incidence of employer-provided health insurance with sticky nominal wages.

PubMed

Sommers, Benjamin D

2005-03-01

This paper addresses two seeming paradoxes in the realm of employer-provided health insurance: First, businesses consistently claim that they bear the burden of the insurance they provide for employees, despite theory and empirical evidence indicating that workers bear the full incidence. Second, benefit generosity and the percentage of premiums paid by employers have decreased in recent decades, despite the preferential tax treatment of employer-paid benefits relative to wages-trends unexplained by the standard incidence model. This paper offers a revised incidence model based on nominal wage rigidity, in an attempt to explain these paradoxes. The model predicts that when the nominal wage constraint binds, some of the burden of increasing insurance premiums will fall on firms, particularly small companies with low-wage employees. In response, firms will reduce employment, decrease benefit generosity, and require larger employee premium contributions. Using Current Population Survey data from 2000-2001, I find evidence for this kind of wage rigidity and its associated impact on the employment and premium contributions of low-wage insured workers during a period of rapid premium growth.

78 FR 7784 - Health Information Technology Policy Committee Nomination Letters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-04

... GOVERNMENT ACCOUNTABILITY OFFICE Health Information Technology Policy Committee Nomination Letters AGENCY: Government Accountability Office (GAO). ACTION: Notice on letters of nomination of candidates... Technology Policy Committee (Health IT Policy Committee) and gave the Comptroller General responsibility for...

Crops Models for Varying Environmental Conditions

NASA Technical Reports Server (NTRS)

Jones, Harry; Cavazzoni, James; Keas, Paul

2001-01-01

New variable environment Modified Energy Cascade (MEC) crop models were developed for all the Advanced Life Support (ALS) candidate crops and implemented in SIMULINK. The MEC models are based on the Volk, Bugbee, and Wheeler Energy Cascade (EC) model and are derived from more recent Top-Level Energy Cascade (TLEC) models. The MEC models simulate crop plant responses to day-to-day changes in photosynthetic photon flux, photoperiod, carbon dioxide level, temperature, and relative humidity. The original EC model allows changes in light energy but uses a less accurate linear approximation. The simulation outputs of the new MEC models for constant nominal environmental conditions are very similar to those of earlier EC models that use parameters produced by the TLEC models. There are a few differences. The new MEC models allow setting the time for seed emergence, have realistic exponential canopy growth, and have corrected harvest dates for potato and tomato. The new MEC models indicate that the maximum edible biomass per meter squared per day is produced at the maximum allowed carbon dioxide level, the nominal temperatures, and the maximum light input. Reducing the carbon dioxide level from the maximum to the minimum allowed in the model reduces crop production significantly. Increasing temperature decreases production more than it decreases the time to harvest, so productivity in edible biomass per meter squared per day is greater at nominal than maximum temperatures, The productivity in edible biomass per meter squared per day is greatest at the maximum light energy input allowed in the model, but the edible biomass produced per light energy input unit is lower than at nominal light levels. Reducing light levels increases light and power use efficiency. The MEC models suggest we can adjust the light energy day-to- day to accommodate power shortages or Lise excess power while monitoring and controlling edible biomass production.

catcher: A Software Program to Detect Answer Copying in Multiple-Choice Tests Based on Nominal Response Model

ERIC Educational Resources Information Center

Kalender, Ilker

2012-01-01

catcher is a software program designed to compute the [omega] index, a common statistical index for the identification of collusions (cheating) among examinees taking an educational or psychological test. It requires (a) responses and (b) ability estimations of individuals, and (c) item parameters to make computations and outputs the results of…

Lessons learned from the AIRS pre-flight radiometric calibration

NASA Astrophysics Data System (ADS)

Pagano, Thomas S.; Aumann, Hartmut H.; Weiler, Margie

2013-09-01

The Atmospheric Infrared Sounder (AIRS) instrument flies on the NASA Aqua satellite and measures the upwelling hyperspectral earth radiance in the spectral range of 3.7-15.4 μm with a nominal ground resolution at nadir of 13.5 km. The AIRS spectra are achieved using a temperature controlled grating spectrometer and HgCdTe infrared linear arrays providing 2378 channels with a nominal spectral resolution of approximately 1200. The AIRS pre-flight tests that impact the radiometric calibration include a full system radiometric response (linearity), polarization response, and response vs scan angle (RVS). We re-derive the AIRS instrument radiometric calibration coefficients from the pre-flight polarization measurements, the response vs scan (RVS) angle tests as well as the linearity tests, and a recent lunar roll test that allowed the AIRS to view the moon. The data and method for deriving the coefficients is discussed in detail and the resulting values compared amongst the different tests. Finally, we examine the residual errors in the reconstruction of the external calibrator blackbody radiances and the efficacy of a new radiometric uncertainty model. Results show the radiometric calibration of AIRS to be excellent and the radiometric uncertainty model does a reasonable job of characterizing the errors.

International Space Station Environmental Control and Life Support Emergency Response Verification for Node 1

NASA Technical Reports Server (NTRS)

Williams, David E.

2008-01-01

The International Space Station (ISS) Node 1 Environmental Control and Life Support (ECLS) System is comprised of five subsystems: Atmosphere Control and Supply (ACS), Atmosphere Revitalization (AR), Fire Detection and Suppression (FDS), Temperature and Humidity Control (THC), and Water Recovery and Management (WRM). This paper provides a summary of the Node 1 Emergency Response capability, which includes nominal and off-nominal FDS operation, off nominal ACS operation, and off-nominal THC operation. These subsystems provide the capability to help aid the crew members during an emergency cabin depressurization, a toxic spill, or a fire. The paper will also provide a discussion of the detailed Node 1 ECLS Element Verification methodologies for operation of the Node 1 Emergency Response hardware operations utilized during the Qualification phase.

The Usefulness of the Bock Model for Scoring with Information from Incorrect Responses.

ERIC Educational Resources Information Center

Huynh, Huynh; Casteel, Jim

1987-01-01

In the context of pass/fail decisions, using the Bock multi-nominal latent trait model for moderate-length tests does not produce decisions that differ substantially from those based on the raw scores. The Bock decisions appear to relate less strongly to outside criteria than those based on the raw scores. (Author/JAZ)

Current transformer model with hysteresis for improving the protection response in electrical transmission systems

NASA Astrophysics Data System (ADS)

Matussek, Robert; Dzienis, Cezary; Blumschein, Jörg; Schulte, Horst

2014-12-01

In this paper, a generic enhanced protection current transformer (CT) model with saturation effects and transient behavior is presented. The model is used for the purpose of analysis and design of power system protection algorithms. Three major classes of protection CT have been modeled which all take into account the nonlinear inductance with remanence effects. The transient short-circuit currents in power systems are simulated under CT saturation condition. The response of a common power system protection algorithm with respect to robustness to nominal parameter variations and sensitivity against maloperation is demonstrated by simulation studies.

A Novel Approach to Noise-Filtering Based on a Gain-Scheduling Neural Network Architecture

NASA Technical Reports Server (NTRS)

Troudet, T.; Merrill, W.

1994-01-01

A gain-scheduling neural network architecture is proposed to enhance the noise-filtering efficiency of feedforward neural networks, in terms of both nominal performance and robustness. The synergistic benefits of the proposed architecture are demonstrated and discussed in the context of the noise-filtering of signals that are typically encountered in aerospace control systems. The synthesis of such a gain-scheduled neurofiltering provides the robustness of linear filtering, while preserving the nominal performance advantage of conventional nonlinear neurofiltering. Quantitative performance and robustness evaluations are provided for the signal processing of pitch rate responses to typical pilot command inputs for a modern fighter aircraft model.

Optimization of an electromagnetic linear actuator using a network and a finite element model

NASA Astrophysics Data System (ADS)

Neubert, Holger; Kamusella, Alfred; Lienig, Jens

2011-03-01

Model based design optimization leads to robust solutions only if the statistical deviations of design, load and ambient parameters from nominal values are considered. We describe an optimization methodology that involves these deviations as stochastic variables for an exemplary electromagnetic actuator used to drive a Braille printer. A combined model simulates the dynamic behavior of the actuator and its non-linear load. It consists of a dynamic network model and a stationary magnetic finite element (FE) model. The network model utilizes lookup tables of the magnetic force and the flux linkage computed by the FE model. After a sensitivity analysis using design of experiment (DoE) methods and a nominal optimization based on gradient methods, a robust design optimization is performed. Selected design variables are involved in form of their density functions. In order to reduce the computational effort we use response surfaces instead of the combined system model obtained in all stochastic analysis steps. Thus, Monte-Carlo simulations can be applied. As a result we found an optimum system design meeting our requirements with regard to function and reliability.

Relational vs. attributive interpretation of nominal compounds differentially engages angular gyrus and anterior temporal lobe

PubMed Central

Boylan, Christine; Trueswell, John C.; Thompson-Schill, Sharon L.

2018-01-01

The angular gyrus (AG) and anterior temporal lobe (ATL) have been found to respond to a number of tasks involving combinatorial processing. In this study, we investigate the conceptual combination of nominal compounds, and ask whether ATL/AG activity is modulated by the type of combinatorial operation applied to a nominal compound. We compare relational and attributive interpretations of nominal compounds and find that ATL and AG both discriminate these two types, but in distinct ways. While right AG demonstrated greater positive task-responsive activity for relational compounds, there was a greater negative deflection in the BOLD response in left AG for relational compounds. In left ATL, we found an earlier peak in subjects’ BOLD response curves for attributive interpretations. In other words, we observed dissociations in both AG and ATL between relational and attributive nominal compounds, with regard to magnitude in the former and to timing in the latter. These findings expand on prior studies that posit roles for both AG and ATL in conceptual processing generally, and in conceptual combination specifically, by indicating possible functional specializations of these two regions within a larger conceptual knowledge network. PMID:28236762

NASA Occupant Protection Standards Development

NASA Technical Reports Server (NTRS)

Somers, Jeffrey T.; Gernhardt, Michael A.; Lawrence, Charles

2011-01-01

Current National Aeronautics and Space Administration (NASA) occupant protection standards and requirements are based on extrapolations of biodynamic models, which were based on human tests performed under pre-Space Shuttle human flight programs where the occupants were in different suit and seat configurations than is expected for the Multi Purpose Crew Vehicle (MPCV) and Commercial Crew programs. As a result, there is limited statistical validity to the occupant protection standards. Furthermore, the current standards and requirements have not been validated in relevant spaceflight suit, seat configurations or loading conditions. The objectives of this study were to develop new standards and requirements for occupant protection and rigorously validate these new standards with sub-injurious human testing. To accomplish these objectives we began by determining which critical injuries NASA would like to protect for. We then defined the anthropomorphic test device (ATD) and the associated injury metrics of interest. Finally, we conducted a literature review of available data for the Test Device for Human Occupant Restraint New Technology (THOR-NT) ATD to determine injury assessment reference values (IARV) to serve as a baseline for further development. To better understand NASA s environment, we propose conducting sub-injurious human testing in spaceflight seat and suit configurations with spaceflight dynamic loads, with a sufficiently high number of subjects to validate no injury during nominal landing loads. In addition to validate nominal loads, the THOR-NT ATD will be tested in the same conditions as the human volunteers, allowing correlation between human and ATD responses covering the Orion nominal landing environment and commercial vehicle expected nominal environments. All testing will be conducted without the suit and with the suit to ascertain the contribution of the suit to human and ATD responses. In addition to the testing campaign proposed, additional data analysis is proposed to mine existing human injury and response data from other sources, including military volunteer testing, automotive Crash Injury Research Engineering Network (CIREN), and IndyCar impact and injury data. These data sources can allow a better extrapolation of the ATD responses to off-nominal conditions above the nominal range that can safely be tested. These elements will be used to develop injury risk functions for each of the injury metrics measured from the ATD. These risk functions would serve as the basis for the NASA standards. Finally, we propose defining standard test methodology for evaluating future spacecraft designs against the IARVs, including developing a star-rating system to allow crew safety comparisons between vehicles.

A Vehicle Management End-to-End Testing and Analysis Platform for Validation of Mission and Fault Management Algorithms to Reduce Risk for NASA's Space Launch System

NASA Technical Reports Server (NTRS)

Trevino, Luis; Patterson, Jonathan; Teare, David; Johnson, Stephen

2015-01-01

The engineering development of the new Space Launch System (SLS) launch vehicle requires cross discipline teams with extensive knowledge of launch vehicle subsystems, information theory, and autonomous algorithms dealing with all operations from pre-launch through on orbit operations. The characteristics of these spacecraft systems must be matched with the autonomous algorithm monitoring and mitigation capabilities for accurate control and response to abnormal conditions throughout all vehicle mission flight phases, including precipitating safing actions and crew aborts. This presents a large and complex system engineering challenge, which is being addressed in part by focusing on the specific subsystems involved in the handling of off-nominal mission and fault tolerance with response management. Using traditional model based system and software engineering design principles from the Unified Modeling Language (UML) and Systems Modeling Language (SysML), the Mission and Fault Management (M&FM) algorithms for the vehicle are crafted and vetted in specialized Integrated Development Teams (IDTs) composed of multiple development disciplines such as Systems Engineering (SE), Flight Software (FSW), Safety and Mission Assurance (S&MA) and the major subsystems and vehicle elements such as Main Propulsion Systems (MPS), boosters, avionics, Guidance, Navigation, and Control (GNC), Thrust Vector Control (TVC), and liquid engines. These model based algorithms and their development lifecycle from inception through Flight Software certification are an important focus of this development effort to further insure reliable detection and response to off-nominal vehicle states during all phases of vehicle operation from pre-launch through end of flight. NASA formed a dedicated M&FM team for addressing fault management early in the development lifecycle for the SLS initiative. As part of the development of the M&FM capabilities, this team has developed a dedicated testbed that integrates specific M&FM algorithms, specialized nominal and off-nominal test cases, and vendor-supplied physics-based launch vehicle subsystem models. Additionally, the team has developed processes for implementing and validating these algorithms for concept validation and risk reduction for the SLS program. The flexibility of the Vehicle Management End-to-end Testbed (VMET) enables thorough testing of the M&FM algorithms by providing configurable suites of both nominal and off-nominal test cases to validate the developed algorithms utilizing actual subsystem models such as MPS. The intent of VMET is to validate the M&FM algorithms and substantiate them with performance baselines for each of the target vehicle subsystems in an independent platform exterior to the flight software development infrastructure and its related testing entities. In any software development process there is inherent risk in the interpretation and implementation of concepts into software through requirements and test cases into flight software compounded with potential human errors throughout the development lifecycle. Risk reduction is addressed by the M&FM analysis group working with other organizations such as S&MA, Structures and Environments, GNC, Orion, the Crew Office, Flight Operations, and Ground Operations by assessing performance of the M&FM algorithms in terms of their ability to reduce Loss of Mission and Loss of Crew probabilities. In addition, through state machine and diagnostic modeling, analysis efforts investigate a broader suite of failure effects and associated detection and responses that can be tested in VMET to ensure that failures can be detected, and confirm that responses do not create additional risks or cause undesired states through interactive dynamic effects with other algorithms and systems. VMET further contributes to risk reduction by prototyping and exercising the M&FM algorithms early in their implementation and without any inherent hindrances such as meeting FSW processor scheduling constraints due to their target platform - ARINC 653 partitioned OS, resource limitations, and other factors related to integration with other subsystems not directly involved with M&FM such as telemetry packing and processing. The baseline plan for use of VMET encompasses testing the original M&FM algorithms coded in the same C++ language and state machine architectural concepts as that used by Flight Software. This enables the development of performance standards and test cases to characterize the M&FM algorithms and sets a benchmark from which to measure the effectiveness of M&FM algorithms performance in the FSW development and test processes.

Fatigue life prediction modeling for turbine hot section materials

NASA Technical Reports Server (NTRS)

Halford, G. R.; Meyer, T. G.; Nelson, R. S.; Nissley, D. M.; Swanson, G. A.

1989-01-01

A major objective of the fatigue and fracture efforts under the NASA Hot Section Technology (HOST) program was to significantly improve the analytic life prediction tools used by the aeronautical gas turbine engine industry. This was achieved in the areas of high-temperature thermal and mechanical fatigue of bare and coated high-temperature superalloys. The cyclic crack initiation and propagation resistance of nominally isotropic polycrystalline and highly anisotropic single crystal alloys were addressed. Life prediction modeling efforts were devoted to creep-fatigue interaction, oxidation, coatings interactions, multiaxiality of stress-strain states, mean stress effects, cumulative damage, and thermomechanical fatigue. The fatigue crack initiation life models developed to date include the Cyclic Damage Accumulation (CDA) and the Total Strain Version of Strainrange Partitioning (TS-SRP) for nominally isotropic materials, and the Tensile Hysteretic Energy Model for anisotropic superalloys. A fatigue model is being developed based upon the concepts of Path-Independent Integrals (PII) for describing cyclic crack growth under complex nonlinear response at the crack tip due to thermomechanical loading conditions. A micromechanistic oxidation crack extension model was derived. The models are described and discussed.

Fatigue life prediction modeling for turbine hot section materials

NASA Technical Reports Server (NTRS)

Halford, G. R.; Meyer, T. G.; Nelson, R. S.; Nissley, D. M.; Swanson, G. A.

1988-01-01

A major objective of the fatigue and fracture efforts under the Hot Section Technology (HOST) program was to significantly improve the analytic life prediction tools used by the aeronautical gas turbine engine industry. This was achieved in the areas of high-temperature thermal and mechanical fatigue of bare and coated high-temperature superalloys. The cyclic crack initiation and propagation resistance of nominally isotropic polycrystalline and highly anisotropic single crystal alloys were addressed. Life prediction modeling efforts were devoted to creep-fatigue interaction, oxidation, coatings interactions, multiaxiality of stress-strain states, mean stress effects, cumulative damage, and thermomechanical fatigue. The fatigue crack initiation life models developed to date include the Cyclic Damage Accumulation (CDA) and the Total Strain Version of Strainrange Partitioning (TS-SRP) for nominally isotropic materials, and the Tensile Hysteretic Energy Model for anisotropic superalloys. A fatigue model is being developed based upon the concepts of Path-Independent Integrals (PII) for describing cyclic crack growth under complex nonlinear response at the crack tip due to thermomechanical loading conditions. A micromechanistic oxidation crack extension model was derived. The models are described and discussed.

Advanced Modeling and Uncertainty Quantification for Flight Dynamics; Interim Results and Challenges

NASA Technical Reports Server (NTRS)

Hyde, David C.; Shweyk, Kamal M.; Brown, Frank; Shah, Gautam

2014-01-01

As part of the NASA Vehicle Systems Safety Technologies (VSST), Assuring Safe and Effective Aircraft Control Under Hazardous Conditions (Technical Challenge #3), an effort is underway within Boeing Research and Technology (BR&T) to address Advanced Modeling and Uncertainty Quantification for Flight Dynamics (VSST1-7). The scope of the effort is to develop and evaluate advanced multidisciplinary flight dynamics modeling techniques, including integrated uncertainties, to facilitate higher fidelity response characterization of current and future aircraft configurations approaching and during loss-of-control conditions. This approach is to incorporate multiple flight dynamics modeling methods for aerodynamics, structures, and propulsion, including experimental, computational, and analytical. Also to be included are techniques for data integration and uncertainty characterization and quantification. This research shall introduce new and updated multidisciplinary modeling and simulation technologies designed to improve the ability to characterize airplane response in off-nominal flight conditions. The research shall also introduce new techniques for uncertainty modeling that will provide a unified database model comprised of multiple sources, as well as an uncertainty bounds database for each data source such that a full vehicle uncertainty analysis is possible even when approaching or beyond Loss of Control boundaries. Methodologies developed as part of this research shall be instrumental in predicting and mitigating loss of control precursors and events directly linked to causal and contributing factors, such as stall, failures, damage, or icing. The tasks will include utilizing the BR&T Water Tunnel to collect static and dynamic data to be compared to the GTM extended WT database, characterizing flight dynamics in off-nominal conditions, developing tools for structural load estimation under dynamic conditions, devising methods for integrating various modeling elements into a real-time simulation capability, generating techniques for uncertainty modeling that draw data from multiple modeling sources, and providing a unified database model that includes nominal plus increments for each flight condition. This paper presents status of testing in the BR&T water tunnel and analysis of the resulting data and efforts to characterize these data using alternative modeling methods. Program challenges and issues are also presented.

Solomon M. Hsiang Receives 2013 Science for Solutions Award: Response

NASA Astrophysics Data System (ADS)

Hsiang, Solomon M.

2014-01-01

I am honored to receive this award, created by Peter Schlosser, nominated by my postdoc advisor Michael Oppenheimer, and alongside my thesis advisor Mark Cane, recipient of this year's Maurice Ewing Medal—all role models and original pioneers in "the application and use of Earth and space sciences to solve societal problems."

The Role of Twinning Deformation on the Hardening Response of Polycrystalline Magnesium from Discrete Dislocation Dynamics Simulations

DTIC Science & Technology

2015-01-01

polycrystalline magnesium (Mg) was studied using three-dimensional discrete dislocation dynamics ( DDD ). A systematic interaction model between dislocations...and f1012g tension twin boundaries (TBs) was proposed and introduced into the DDD framework. In addition, a nominal grain boundary (GB) model based...dynamics ( DDD ). A systematic interaction model between dislocations and f10 12g tension twin boundaries (TBs) was proposed and introduced into the DDD

Comparison of dislocation density tensor fields derived from discrete dislocation dynamics and crystal plasticity simulations of torsion

DOE PAGES

Jones, Reese E.; Zimmerman, Jonathan A.; Po, Giacomo; ...

2016-02-01

Accurate simulation of the plastic deformation of ductile metals is important to the design of structures and components to performance and failure criteria. Many techniques exist that address the length scales relevant to deformation processes, including dislocation dynamics (DD), which models the interaction and evolution of discrete dislocation line segments, and crystal plasticity (CP), which incorporates the crystalline nature and restricted motion of dislocations into a higher scale continuous field framework. While these two methods are conceptually related, there have been only nominal efforts focused at the global material response that use DD-generated information to enhance the fidelity of CPmore » models. To ascertain to what degree the predictions of CP are consistent with those of DD, we compare their global and microstructural response in a number of deformation modes. After using nominally homogeneous compression and shear deformation dislocation dynamics simulations to calibrate crystal plasticity ow rule parameters, we compare not only the system-level stress-strain response of prismatic wires in torsion but also the resulting geometrically necessary dislocation density fields. To establish a connection between explicit description of dislocations and the continuum assumed with crystal plasticity simulations we ascertain the minimum length-scale at which meaningful dislocation density fields appear. Furthermore, our results show that, for the case of torsion, that the two material models can produce comparable spatial dislocation density distributions.« less

Modeling Off-Nominal Recovery in NextGen Terminal-Area Operations

NASA Technical Reports Server (NTRS)

Callantine, Todd J.

2011-01-01

Robust schedule-based arrival management requires efficient recovery from off-nominal situations. This paper presents research on modeling off-nominal situations and plans for recovering from them using TRAC, a route/airspace design, fast-time simulation, and analysis tool for studying NextGen trajectory-based operations. The paper provides an overview of a schedule-based arrival-management concept and supporting controller tools, then describes TRAC implementations of methods for constructing off-nominal scenarios, generating trajectory options to meet scheduling constraints, and automatically producing recovery plans.

Expressed Satisfaction with the Nominal Group Technique among Change Agents. A Summary Report of Research. Departmental Information Bulletin 86-1.

ERIC Educational Resources Information Center

Gresham, Jon N.

A study examined the different degrees of satisfaction with the nominal group technique (NGT) felt by policymakers and change agents with differing professional backgrounds and responsibilities who participated in nominal groups. A total of 206 participants at four conferences at Texas A&M University (international food and water policy, Texas…

Evaluating Nextgen Closely Spaced Parallel Operations Concepts with Validated Human Performance Models: Flight Deck Guidelines

NASA Technical Reports Server (NTRS)

Hooey, Becky Lee; Gore, Brian Francis; Mahlstedt, Eric; Foyle, David C.

2013-01-01

The objectives of the current research were to develop valid human performance models (HPMs) of approach and land operations; use these models to evaluate the impact of NextGen Closely Spaced Parallel Operations (CSPO) on pilot performance; and draw conclusions regarding flight deck display design and pilot-ATC roles and responsibilities for NextGen CSPO concepts. This document presents guidelines and implications for flight deck display designs and candidate roles and responsibilities. A companion document (Gore, Hooey, Mahlstedt, & Foyle, 2013) provides complete scenario descriptions and results including predictions of pilot workload, visual attention and time to detect off-nominal events.

Dynamic Modeling of ALS Systems

NASA Technical Reports Server (NTRS)

Jones, Harry

2002-01-01

The purpose of dynamic modeling and simulation of Advanced Life Support (ALS) systems is to help design them. Static steady state systems analysis provides basic information and is necessary to guide dynamic modeling, but static analysis is not sufficient to design and compare systems. ALS systems must respond to external input variations and internal off-nominal behavior. Buffer sizing, resupply scheduling, failure response, and control system design are aspects of dynamic system design. We develop two dynamic mass flow models and use them in simulations to evaluate systems issues, optimize designs, and make system design trades. One model is of nitrogen leakage in the space station, the other is of a waste processor failure in a regenerative life support system. Most systems analyses are concerned with optimizing the cost/benefit of a system at its nominal steady-state operating point. ALS analysis must go beyond the static steady state to include dynamic system design. All life support systems exhibit behavior that varies over time. ALS systems must respond to equipment operating cycles, repair schedules, and occasional off-nominal behavior or malfunctions. Biological components, such as bioreactors, composters, and food plant growth chambers, usually have operating cycles or other complex time behavior. Buffer sizes, material stocks, and resupply rates determine dynamic system behavior and directly affect system mass and cost. Dynamic simulation is needed to avoid the extremes of costly over-design of buffers and material reserves or system failure due to insufficient buffers and lack of stored material.

High-Fidelity Multi-Rotor Unmanned Aircraft System Simulation Development for Trajectory Prediction Under Off-Nominal Flight Dynamics

NASA Technical Reports Server (NTRS)

Foster, John V.; Hartman, David C.

2017-01-01

The NASA Unmanned Aircraft System (UAS) Traffic Management (UTM) project is conducting research to enable civilian low-altitude airspace and UAS operations. A goal of this project is to develop probabilistic methods to quantify risk during failures and off nominal flight conditions. An important part of this effort is the reliable prediction of feasible trajectories during off-nominal events such as control failure, atmospheric upsets, or navigation anomalies that can cause large deviations from the intended flight path or extreme vehicle upsets beyond the normal flight envelope. Few examples of high-fidelity modeling and prediction of off-nominal behavior for small UAS (sUAS) vehicles exist, and modeling requirements for accurately predicting flight dynamics for out-of-envelope or failure conditions are essentially undefined. In addition, the broad range of sUAS aircraft configurations already being fielded presents a significant modeling challenge, as these vehicles are often very different from one another and are likely to possess dramatically different flight dynamics and resultant trajectories and may require different modeling approaches to capture off-nominal behavior. NASA has undertaken an extensive research effort to define sUAS flight dynamics modeling requirements and develop preliminary high fidelity six degree-of-freedom (6-DOF) simulations capable of more closely predicting off-nominal flight dynamics and trajectories. This research has included a literature review of existing sUAS modeling and simulation work as well as development of experimental testing methods to measure and model key components of propulsion, airframe and control characteristics. The ultimate objective of these efforts is to develop tools to support UTM risk analyses and for the real-time prediction of off-nominal trajectories for use in the UTM Risk Assessment Framework (URAF). This paper focuses on modeling and simulation efforts for a generic quad-rotor configuration typical of many commercial vehicles in use today. An overview of relevant off-nominal multi-rotor behaviors will be presented to define modeling goals and to identify the prediction capability lacking in simplified models of multi-rotor performance. A description of recent NASA wind tunnel testing of multi-rotor propulsion and airframe components will be presented illustrating important experimental and data acquisition methods, and a description of preliminary propulsion and airframe models will be presented. Lastly, examples of predicted off-nominal flight dynamics and trajectories from the simulation will be presented.

Statistical Significance and Baseline Monitoring.

DTIC Science & Technology

1984-07-01

impacted at once........................... 24 6 Observed versus nominal a levels for multivariate tests of data sets (50 runs of 4 groups each...cumulative proportion of the observations found for each nominal level. The results of the comparisons of the observed versus nominal a levels for the...a values are always higher than nominal levels. Virtual- . .,ly all nominal a levels are below 0.20. In other words, the discriminant analysis models

Generalized Partial Least Squares Approach for Nominal Multinomial Logit Regression Models with a Functional Covariate

ERIC Educational Resources Information Center

Albaqshi, Amani Mohammed H.

2017-01-01

Functional Data Analysis (FDA) has attracted substantial attention for the last two decades. Within FDA, classifying curves into two or more categories is consistently of interest to scientists, but multi-class prediction within FDA is challenged in that most classification tools have been limited to binary response applications. The functional…

Terrestrial Microgravity Model and Threshold Gravity Simulation sing Magnetic Levitation

NASA Technical Reports Server (NTRS)

Ramachandran, N.

2005-01-01

What is the threshold gravity (minimum gravity level) required for the nominal functioning of the human system? What dosage is required? Do human cell lines behave differently in microgravity in response to an external stimulus? The critical need for such a gravity simulator is emphasized by recent experiments on human epithelial cells and lymphocytes on the Space Shuttle clearly showing that cell growth and function are markedly different from those observed terrestrially. Those differences are also dramatic between cells grown in space and those in Rotating Wall Vessels (RWV), or NASA bioreactor often used to simulate microgravity, indicating that although morphological growth patterns (three dimensional growth) can be successiblly simulated using RWVs, cell function performance is not reproduced - a critical difference. If cell function is dramatically affected by gravity off-loading, then cell response to stimuli such as radiation, stress, etc. can be very different from terrestrial cell lines. Yet, we have no good gravity simulator for use in study of these phenomena. This represents a profound shortcoming for countermeasures research. We postulate that we can use magnetic levitation of cells and tissue, through the use of strong magnetic fields and field gradients, as a terrestrial microgravity model to study human cells. Specific objectives of the research are: 1. To develop a tried, tested and benchmarked terrestrial microgravity model for cell culture studies; 2. Gravity threshold determination; 3. Dosage (magnitude and duration) of g-level required for nominal functioning of cells; 4. Comparisons of magnetic levitation model to other models such as RWV, hind limb suspension, etc. and 5. Cellular response to reduced gravity levels of Moon and Mars.

Ray Tracing through the Edge Focusing of Rectangular Benders and an Improved Model for the Los Alamos Proton Storage Ring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kolski, Jeffrey S.; Barlow, David B.; Macek, Robert J.

2011-01-01

Particle ray tracing through simulated 3D magnetic fields was executed to investigate the effective quadrupole strength of the edge focusing of the rectangular bending magnets in the Los Alamos Proton Storage Ring (PSR). The particle rays receive a kick in the edge field of the rectangular dipole. A focal length may be calculated from the particle tracking and related to the fringe field integral (FINT) model parameter. This tech note introduces the baseline lattice model of the PSR and motivates the need for an improvement in the baseline model's vertical tune prediction, which differs from measurement by .05. An improvedmore » model of the PSR is created by modifying the fringe field integral parameter to those suggested by the ray tracing investigation. This improved model is then verified against measurement at the nominal PSR operating set point and at set points far away from the nominal operating conditions. Lastly, Linear Optics from Closed Orbits (LOCO) is employed in an orbit response matrix method for model improvement to verify the quadrupole strengths of the improved model.« less

Assessing the Utility of the Nominal Group Technique as a Consensus-Building Tool in Extension-Led Avian Influenza Response Planning

ERIC Educational Resources Information Center

Kline, Terence R.

2013-01-01

The intent of the project described was to apply the Nominal Group Technique (NGT) to achieve a consensus on Avian Influenza (AI) planning in Northeastern Ohio. Nominal Group Technique is a process first developed by Delbecq, Vande Ven, and Gustafsen (1975) to allow all participants to have an equal say in an open forum setting. A very diverse…

Preliminary Study into Shell Mold Casting of Nominal 60-Nitinol Alloy

DTIC Science & Technology

The present study was initiated to determine the feasibility of shell mold casting nominal 60- Nitinol into suitable EOD (Explosive Ordnance Disposal...surface finish and definition and property response of cast alloy. Based upon the results, 60- Nitinol appears quite suited to shell molding and a...concern lies in the casting porosity associated with the relatively large liquid-to-solid shrinkage of nominal 60- Nitinol .

Terrestrial Microgravity Model and Threshold Gravity Simulation using Magnetic Levitation

NASA Technical Reports Server (NTRS)

Ramachandran, N.

2005-01-01

What is the threshold gravity (minimum gravity level) required for the nominal functioning of the human system? What dosage is required? Do human cell lines behave differently in microgravity in response to an external stimulus? The critical need for such a gravity simulator is emphasized by recent experiments on human epithelial cells and lymphocytes on the Space Shuttle clearly showing that cell growth and function are markedly different from those observed terrestrially. Those differences are also dramatic between cells grown in space and those in Rotating Wall Vessels (RWV), or NASA bioreactor often used to simulate microgravity, indicating that although morphological growth patterns (three dimensional growth) can be successfully simulated using RWVs, cell function performance is not reproduced - a critical difference. If cell function is dramatically affected by gravity off-loading, then cell response to stimuli such as radiation, stress, etc. can be very different from terrestrial cell lines. Yet, we have no good gravity simulator for use in study of these phenomena. This represents a profound shortcoming for countermeasures research. We postulate that we can use magnetic levitation of cells and tissue, through the use of strong magnetic fields and field gradients, as a terrestrial microgravity model to study human cells. Specific objectives of the research are: 1. To develop a tried, tested and benchmarked terrestrial microgravity model for cell culture studies; 2. Gravity threshold determination; 3. Dosage (magnitude and duration) of g-level required for nominal functioning of cells; 4. Comparisons of magnetic levitation model to other models such as RWV, hind limb suspension, etc. and 5. Cellular response to reduced gravity levels of Moon and Mars. The paper will discuss experiments md modeling work to date in support of this project.

Time-accurate unsteady flow simulations supporting the SRM T+68-second pressure spike anomaly investigation (STS-54B)

NASA Astrophysics Data System (ADS)

Dougherty, N. S.; Burnette, D. W.; Holt, J. B.; Matienzo, Jose

1993-07-01

Time-accurate unsteady flow simulations are being performed supporting the SRM T+68sec pressure 'spike' anomaly investigation. The anomaly occurred in the RH SRM during the STS-54 flight (STS-54B) but not in the LH SRM (STS-54A) causing a momentary thrust mismatch approaching the allowable limit at that time into the flight. Full-motor internal flow simulations using the USA-2D axisymmetric code are in progress for the nominal propellant burn-back geometry and flow conditions at T+68-sec--Pc = 630 psi, gamma = 1.1381, T(sub c) = 6200 R, perfect gas without aluminum particulate. In a cooperative effort with other investigation team members, CFD-derived pressure loading on the NBR and castable inhibitors was used iteratively to obtain nominal deformed geometry of each inhibitor, and the deformed (bent back) inhibitor geometry was entered into this model. Deformed geometry was computed using structural finite-element models. A solution for the unsteady flow has been obtained for the nominal flow conditions (existing prior to the occurrence of the anomaly) showing sustained standing pressure oscillations at nominally 14.5 Hz in the motor IL acoustic mode that flight and static test data confirm to be normally present at this time. Average mass flow discharged from the nozzle was confirmed to be the nominal expected (9550 lbm/sec). The local inlet boundary condition is being perturbed at the location of the presumed reconstructed anomaly as identified by interior ballistics performance specialist team members. A time variation in local mass flow is used to simulate sudden increase in burning area due to localized propellant grain cracks. The solution will proceed to develop a pressure rise (proportional to total mass flow rate change squared). The volume-filling time constant (equivalent to 0.5 Hz) comes into play in shaping the rise rate of the developing pressure 'spike' as it propagates at the speed of sound in both directions to the motor head end and nozzle. The objectives of the present analysis are to: (1) capture the dynamic responses of the motor combustion gas flow to correlate with available low-frequency (less than 12.5 sample/sec) data and (2) observe the high-frequency (up to 50 Hz) characteristics of the response to determine any potentials for dynamic coupling.

Test Design Optimization in CAT Early Stage with the Nominal Response Model

ERIC Educational Resources Information Center

Passos, Valeria Lima; Berger, Martijn P. F.; Tan, Frans E.

2007-01-01

The early stage of computerized adaptive testing (CAT) refers to the phase of the trait estimation during the administration of only a few items. This phase can be characterized by bias and instability of estimation. In this study, an item selection criterion is introduced in an attempt to lessen this instability: the D-optimality criterion. A…

Review of probabilistic analysis of dynamic response of systems with random parameters

NASA Technical Reports Server (NTRS)

Kozin, F.; Klosner, J. M.

1989-01-01

The various methods that have been studied in the past to allow probabilistic analysis of dynamic response for systems with random parameters are reviewed. Dynamic response may have been obtained deterministically if the variations about the nominal values were small; however, for space structures which require precise pointing, the variations about the nominal values of the structural details and of the environmental conditions are too large to be considered as negligible. These uncertainties are accounted for in terms of probability distributions about their nominal values. The quantities of concern for describing the response of the structure includes displacements, velocities, and the distributions of natural frequencies. The exact statistical characterization of the response would yield joint probability distributions for the response variables. Since the random quantities will appear as coefficients, determining the exact distributions will be difficult at best. Thus, certain approximations will have to be made. A number of techniques that are available are discussed, even in the nonlinear case. The methods that are described were: (1) Liouville's equation; (2) perturbation methods; (3) mean square approximate systems; and (4) nonlinear systems with approximation by linear systems.

Predicting The Type Of Pregnancy Using Flexible Discriminate Analysis And Artificial Neural Networks: A Comparison Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hooman, A.; Mohammadzadeh, M

Some medical and epidemiological surveys have been designed to predict a nominal response variable with several levels. With regard to the type of pregnancy there are four possible states: wanted, unwanted by wife, unwanted by husband and unwanted by couple. In this paper, we have predicted the type of pregnancy, as well as the factors influencing it using three different models and comparing them. Regarding the type of pregnancy with several levels, we developed a multinomial logistic regression, a neural network and a flexible discrimination based on the data and compared their results using tow statistical indices: Surface under curvemore » (ROC) and kappa coefficient. Based on these tow indices, flexible discrimination proved to be a better fit for prediction on data in comparison to other methods. When the relations among variables are complex, one can use flexible discrimination instead of multinomial logistic regression and neural network to predict the nominal response variables with several levels in order to gain more accurate predictions.« less

Stakeholders identify similar barriers but different strategies to facilitate return-to-work: A vignette of a worker with an upper extremity condition.

PubMed

Peters, Susan E; Truong, Anthony P; Johnston, Venerina

2018-01-01

Stakeholders involved in the return-to-work (RTW) process have different roles and qualificationsOBJECTIVE:To explore the perspectives of Australian stakeholders of the RTW barriers and strategies for a worker with an upper extremity condition and a complex workers' compensation case. Using a case vignette, stakeholders were asked to identify barriers and recommend strategies to facilitate RTW. Content analysis was performed on the open-ended responses. The responses were categorised into RTW barriers and strategies using the biopsychosocial model. Pearson's Chi Square and ANOVA were performed to establish group differences. 621 participants (488 healthcare providers (HCPs), 62 employers, 55 insurers and 16 lawyers) identified 36 barriers (31 modifiable): 4 demographic; 8 biological; 15 psychological and 9 social barriers. 484 participants reported 16 RTW strategies: 4 biological; 6 psychological and 6 social strategies. 'Work relationship stressors' (83.4%) and 'Personal relationship stressors' (64.7%) were the most frequently nominated barriers. HCPs most frequently nominated 'Pain management' (49.6%), while employers, insurers and lawyers nominated 'RTW planning/Suitable duties programs' (40.5%; 42.9%; 80%). Stakeholders perceived similar barriers for RTW but recommended different strategies. Stakeholders appeared to be more proficient in identifying barriers than recommending strategies. Future research should focus on tools to both identify RTW barriers and direct intervention.

Thompson Receives 2013 Ocean Sciences Early Career Award: Response

NASA Astrophysics Data System (ADS)

Thompson, Andrew

2014-09-01

I would like to thank my nominator, Jess Adkins, as well as my supporters for their contributions to my nomination and the AGU Ocean Sciences section for its selection. It is an honor to join the past recipients of this award.

Aviation Safety: Modeling and Analyzing Complex Interactions between Humans and Automated Systems

NASA Technical Reports Server (NTRS)

Rungta, Neha; Brat, Guillaume; Clancey, William J.; Linde, Charlotte; Raimondi, Franco; Seah, Chin; Shafto, Michael

2013-01-01

The on-going transformation from the current US Air Traffic System (ATS) to the Next Generation Air Traffic System (NextGen) will force the introduction of new automated systems and most likely will cause automation to migrate from ground to air. This will yield new function allocations between humans and automation and therefore change the roles and responsibilities in the ATS. Yet, safety in NextGen is required to be at least as good as in the current system. We therefore need techniques to evaluate the safety of the interactions between humans and automation. We think that current human factor studies and simulation-based techniques will fall short in front of the ATS complexity, and that we need to add more automated techniques to simulations, such as model checking, which offers exhaustive coverage of the non-deterministic behaviors in nominal and off-nominal scenarios. In this work, we present a verification approach based both on simulations and on model checking for evaluating the roles and responsibilities of humans and automation. Models are created using Brahms (a multi-agent framework) and we show that the traditional Brahms simulations can be integrated with automated exploration techniques based on model checking, thus offering a complete exploration of the behavioral space of the scenario. Our formal analysis supports the notion of beliefs and probabilities to reason about human behavior. We demonstrate the technique with the Ueberligen accident since it exemplifies authority problems when receiving conflicting advices from human and automated systems.

Three decision-making aids: brainstorming, nominal group, and Delphi technique.

PubMed

McMurray, A R

1994-01-01

The methods of brainstorming, Nominal Group Technique, and the Delphi technique can be important resources for nursing staff development educators who wish to expand their decision-making skills. Staff development educators may find opportunities to use these methods for such tasks as developing courses, setting departmental goals, and forecasting trends for planning purposes. Brainstorming, Nominal Group Technique, and the Delphi technique provide a structured format that helps increase the quantity and quality of participant responses.

Dynamic Response and Maneuvering Strategies of a Hybrid Autonomous Underwater Vehicle in Hovering

DTIC Science & Technology

2009-02-01

Highlights of ECC’99, pages 391– 449. Springer, 1999. [7] F. Allgower, R. Findeisen , and Z. K. Nagy. Nonlinear model predictive con- trol: From theory...vehicle. In OCEANS, pages 2129–2134. MTS/IEEE, 2005. [17] M. Diehl, R. Findeisen , F. Allgower, H. G. Bock, and J. P. Schloder. Nominal stability of real...International Journal of Robust and Nonlinear Control, 18(8):816–830, May 2008. [22] R. Findeisen and F. Allgower. An introduction to nonlinear model

A note on monotonicity of item response functions for ordered polytomous item response theory models.

PubMed

Kang, Hyeon-Ah; Su, Ya-Hui; Chang, Hua-Hua

2018-03-08

A monotone relationship between a true score (τ) and a latent trait level (θ) has been a key assumption for many psychometric applications. The monotonicity property in dichotomous response models is evident as a result of a transformation via a test characteristic curve. Monotonicity in polytomous models, in contrast, is not immediately obvious because item response functions are determined by a set of response category curves, which are conceivably non-monotonic in θ. The purpose of the present note is to demonstrate strict monotonicity in ordered polytomous item response models. Five models that are widely used in operational assessments are considered for proof: the generalized partial credit model (Muraki, 1992, Applied Psychological Measurement, 16, 159), the nominal model (Bock, 1972, Psychometrika, 37, 29), the partial credit model (Masters, 1982, Psychometrika, 47, 147), the rating scale model (Andrich, 1978, Psychometrika, 43, 561), and the graded response model (Samejima, 1972, A general model for free-response data (Psychometric Monograph no. 18). Psychometric Society, Richmond). The study asserts that the item response functions in these models strictly increase in θ and thus there exists strict monotonicity between τ and θ under certain specified conditions. This conclusion validates the practice of customarily using τ in place of θ in applied settings and provides theoretical grounds for one-to-one transformations between the two scales. © 2018 The British Psychological Society.

Modeling Off-Nominal Behavior in SysML

NASA Technical Reports Server (NTRS)

Day, John C.; Donahue, Kenneth; Ingham, Michel; Kadesch, Alex; Kennedy, Andrew K.; Post, Ethan

2012-01-01

Specification and development of fault management functionality in systems is performed in an ad hoc way - more of an art than a science. Improvements to system reliability, availability, safety and resilience will be limited without infusion of additional formality into the practice of fault management. Key to the formalization of fault management is a precise representation of off-nominal behavior. Using the upcoming Soil Moisture Active-Passive (SMAP) mission for source material, we have modeled the off-nominal behavior of the SMAP system during its initial spin-up activity, using the System Modeling Language (SysML). In the course of developing these models, we have developed generic patterns for capturing off-nominal behavior in SysML. We show how these patterns provide useful ways of reasoning about the system (e.g., checking for completeness and effectiveness) and allow the automatic generation of typical artifacts (e.g., success trees and FMECAs) used in system analyses.

Anticipated Electrical Environment at Phobos: Nominal and Solar Storm Conditions

NASA Technical Reports Server (NTRS)

Farrell, W. M.; Halekas, J. S.; Fatemi, S.; Poppe, A. R.; Hartzell, C.; Marshall, J. R.; Stubbs, T. J.; Zimmerman, M. I.; Zheng, Y.

2017-01-01

A passing coronal mass ejection (CME) will manifest a different response at an airless body compared to a magnetized planet. Specifically,because the regolith-rich surfaces of airless bodies are directly exposed to the variations in the plasma flow, the surfaces are found to undergo anomalous surface charging during the passing of CME fast plasma events. In this study, we model the surface charging expected at Phobos for nominal solar wind conditions and also those associated with disturbed solar wind conditions during the passage of a CME similar to that observed by MAVEN at Mars in early March 2015. We use an ambipolar diffusion model to examine the development of the trailing wake void in the plasma flow behind Phobos and the formation of mini-wakes within obstruction regions like Stickney Crater. We also consider the roving of an astronaut in Stickney Crater for Phobos positioned near 10 hours Local Time relative to Mars. We examine the plasma dissipation of the collected astronaut charge from contact electrification with the regolith.

Evaluating Cellular Instrumentation on Rural Handpumps to Improve Service Delivery-A Longitudinal Study in Rural Rwanda.

PubMed

Nagel, Corey; Beach, Jack; Iribagiza, Chantal; Thomas, Evan A

2015-12-15

In rural sub-Saharan Africa, where handpumps are common, 10-67% are nonfunctional at any one time, and many never get repaired. Increased reliability requires improved monitoring and responsiveness of maintenance providers. In 2014, 181 cellular enabled water pump use sensors were installed in three provinces of Rwanda. In three arms, the nominal maintenance model was compared against a "best practice" circuit rider model, and an "ambulance" service model. In only the ambulance model was the sensor data available to the implementer, and used to dispatch technicians. The study ran for seven months in 2014-2015. In the study period, the nominal maintenance group had a median time to successful repair of approximately 152 days, with a mean per-pump functionality of about 68%. In the circuit rider group, the median time to successful repair was nearly 57 days, with a per-pump functionality mean of nearly 73%. In the ambulance service group, the successful repair interval was nearly 21 days with a functionality mean of nearly 91%. An indicative cost analysis suggests that the cost per functional pump per year is approximately similar between the three models. However, the benefits of reliable water service may justify greater focus on servicing models over installation models.

77 FR 20881 - Unified Carrier Registration Plan Board of Directors; Request for Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-06

... Carrier Industry to the Board of Directors. SUMMARY: FMCSA solicits nominations and applications for... persons to serve as representatives of the motor carrier industry. The Agency will appoint five members from the motor carrier industry. The UCR Plan is responsible for the administration of the UCR...

Threshold Gravity Determination and Artificial Gravity Studies Using Magnetic Levitation

NASA Technical Reports Server (NTRS)

Ramachandran, N.; Leslie, F.

2005-01-01

What is the threshold gravity (minimum gravity level) required for the nominal functioning of the human system? What dosage is required (magnitude and duration)? Do human cell lines behave differently in microgravity in response to an external stimulus? The critical need for a variable gravity simulator is emphasized by recent experiments on human epithelial cells and lymphocytes on the Space Shuttle clearly showing that cell growth and function are markedly different from those observed terrestrially. Those differences are also dramatic between cells grown in space and those in Rotating Wall Vessels (RWV), or NASA bioreactor often used to simulate microgravity, indicating that although morphological growth patterns (three dimensional growth) can be successfully simulated using RWVs, cell function performance is not reproduced - a critical difference. If cell function is dramatically affected by gravity off-loading, then cell response to stimuli such as radiation, stress, etc. can be very different from terrestrial cell lines. Yet, we have no good gravity simulator for use in study of these phenomena. This represents a profound shortcoming for countermeasures research. We postulate that we can use magnetic levitation of cells and tissue, through the use of strong magnetic fields and field gradients, as a terrestrial microgravity model to study human cells. Specific objectives of the research are: 1. To develop a tried, tested and benchmarked terrestrial microgravity model for cell culture studies; 2. Gravity threshold determination; 3. Dosage (magnitude and duration) of g-level required for nominal functioning of cells; 4. Comparisons of magnetic levitation model to other models such as RWV, hind limb suspension, etc. and 5. Cellular response to reduced gravity levels of Moon and Mars.

The Development of Web-based Graphical User Interface for Unified Modeling Data with Multi (Correlated) Responses

NASA Astrophysics Data System (ADS)

Made Tirta, I.; Anggraeni, Dian

2018-04-01

Statistical models have been developed rapidly into various directions to accommodate various types of data. Data collected from longitudinal, repeated measured, clustered data (either continuous, binary, count, or ordinal), are more likely to be correlated. Therefore statistical model for independent responses, such as Generalized Linear Model (GLM), Generalized Additive Model (GAM) are not appropriate. There are several models available to apply for correlated responses including GEEs (Generalized Estimating Equations), for marginal model and various mixed effect model such as GLMM (Generalized Linear Mixed Models) and HGLM (Hierarchical Generalized Linear Models) for subject spesific models. These models are available on free open source software R, but they can only be accessed through command line interface (using scrit). On the othe hand, most practical researchers very much rely on menu based or Graphical User Interface (GUI). We develop, using Shiny framework, standard pull down menu Web-GUI that unifies most models for correlated responses. The Web-GUI has accomodated almost all needed features. It enables users to do and compare various modeling for repeated measure data (GEE, GLMM, HGLM, GEE for nominal responses) much more easily trough online menus. This paper discusses the features of the Web-GUI and illustrates the use of them. In General we find that GEE, GLMM, HGLM gave very closed results.

METCAN: The metal matrix composite analyzer

NASA Technical Reports Server (NTRS)

Hopkins, Dale A.; Murthy, Pappu L. N.

1988-01-01

Metal matrix composites (MMC) are the subject of intensive study and are receiving serious consideration for critical structural applications in advanced aerospace systems. MMC structural analysis and design methodologies are studied. Predicting the mechanical and thermal behavior and the structural response of components fabricated from MMC requires the use of a variety of mathematical models. These models relate stresses to applied forces, stress intensities at the tips of cracks to nominal stresses, buckling resistance to applied force, or vibration response to excitation forces. The extensive research in computational mechanics methods for predicting the nonlinear behavior of MMC are described. This research has culminated in the development of the METCAN (METal Matrix Composite ANalyzer) computer code.

Model implementation for dynamic computation of system cost

NASA Astrophysics Data System (ADS)

Levri, J.; Vaccari, D.

The Advanced Life Support (ALS) Program metric is the ratio of the equivalent system mass (ESM) of a mission based on International Space Station (ISS) technology to the ESM of that same mission based on ALS technology. ESM is a mission cost analog that converts the volume, power, cooling and crewtime requirements of a mission into mass units to compute an estimate of the life support system emplacement cost. Traditionally, ESM has been computed statically, using nominal values for system sizing. However, computation of ESM with static, nominal sizing estimates cannot capture the peak sizing requirements driven by system dynamics. In this paper, a dynamic model for a near-term Mars mission is described. The model is implemented in Matlab/Simulink' for the purpose of dynamically computing ESM. This paper provides a general overview of the crew, food, biomass, waste, water and air blocks in the Simulink' model. Dynamic simulations of the life support system track mass flow, volume and crewtime needs, as well as power and cooling requirement profiles. The mission's ESM is computed, based upon simulation responses. Ultimately, computed ESM values for various system architectures will feed into an optimization search (non-derivative) algorithm to predict parameter combinations that result in reduced objective function values.

Bitz, Ginoux, Jacobson, Nizkorodov, and Yang Receive 2013 Atmospheric Sciences Ascent Awards: Response

NASA Astrophysics Data System (ADS)

Jacobson, Mark Z.

2014-07-01

Thank you, Atmospheric Sciences section of AGU for bestowing this humbling honor on me. Thank you, Dr. Ramanathan, for your gracious nomination. Thank you to all my mentors, colleagues, students, special friends, parents, children, and even critics, over the years who supported my pushing the envelope to better understand the impacts of black carbon on climate and air pollution health through numerical modeling.

Systems Modeling for Crew Core Body Temperature Prediction Postlanding

NASA Technical Reports Server (NTRS)

Cross, Cynthia; Ochoa, Dustin

2010-01-01

The Orion Crew Exploration Vehicle, NASA s latest crewed spacecraft project, presents many challenges to its designers including ensuring crew survivability during nominal and off nominal landing conditions. With a nominal water landing planned off the coast of San Clemente, California, off nominal water landings could range from the far North Atlantic Ocean to the middle of the equatorial Pacific Ocean. For all of these conditions, the vehicle must provide sufficient life support resources to ensure that the crew member s core body temperatures are maintained at a safe level prior to crew rescue. This paper will examine the natural environments, environments created inside the cabin and constraints associated with post landing operations that affect the temperature of the crew member. Models of the capsule and the crew members are examined and analysis results are compared to the requirement for safe human exposure. Further, recommendations for updated modeling techniques and operational limits are included.

Rise time and response measurements on a LiSOCl2 cell

NASA Technical Reports Server (NTRS)

Bastien, Caroline; Lecomte, Eric J.

1992-01-01

Dynamic impedance tests were performed on a 180 Ah LiSOCl2 cell in the frame of a short term work contract awarded by Aerospatiale as part of the Hermes Space Plane development work. These tests consisted of rise time and response measurements. The rise time test was performed to show the ability to deliver 4 KW, in the nominal voltage range (75-115 V), within less than 100 microseconds, and after a period at rest of 13 days. The response measurements test consisted of step response and frequency response tests. The frequency response test was performed to characterize the response of the LiSOCl2 cell to a positive or negative load step of 10 A starting from various currents. The test was performed for various depths of discharge and various temperatures. The test results were used to build a mathematical, electrical model of the LiSOCl2 cell which are also presented. The test description, test results, electrical modelization description, and conclusions are presented.

78 FR 12062 - Nominations to the Advisory Committee on Blood and Tissue Safety and Availability

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-21

... Committee is the responsibility of the OASH. The qualified individuals will be nominated to the Secretary of... Mr. James Berger, Senior Advisor for Blood Policy; Division of Blood and Tissue Safety and...: (240) 453-8803. FOR FURTHER INFORMATION CONTACT: Mr. James Berger, Senior Advisor for Blood Policy...

75 FR 66789 - Notice of Intent To Solicit Nominations: Pinedale Anticline Working Group, Wyoming

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-29

... elected office; 2. Are employed by a State Agency responsible for the management of natural resources, land, or water; 3. Are employed as academicians by a natural resource management or natural sciences... group nominating more than one person should indicate its preferred order of appointment selection...

75 FR 16337 - Standards for Business Practices for Interstate Natural Gas Pipelines

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-01

... transportation by power plant operators more difficult. In response to this need, in early 2004, NAESB... receipt and delivery points; and (3) changes to the intraday nomination schedule to increase the number of... conference on the issue of intraday pipeline nomination schedules. In this regard, NGSA asserts that NAESB...

A frequency-domain estimator for use in adaptive control systems

NASA Technical Reports Server (NTRS)

Lamaire, Richard O.; Valavani, Lena; Athans, Michael; Stein, Gunter

1991-01-01

This paper presents a frequency-domain estimator that can identify both a parametrized nominal model of a plant as well as a frequency-domain bounding function on the modeling error associated with this nominal model. This estimator, which we call a robust estimator, can be used in conjunction with a robust control-law redesign algorithm to form a robust adaptive controller.

36 CFR 60.6 - Nominations by the State Historic Preservation Officer under approved State Historic Preservation...

Code of Federal Regulations, 2010 CFR

2010-07-01

... notice of the intent to nominate a property and solicits written comments especially on the significance... State is responsible for notifying only those owners whose names appear on the list consulted. Where there is more than one owner on the list, each separate owner shall be notified. The State shall send...

ERP evidence for different strategies in the processing of case markers in native speakers and non-native learners

PubMed Central

Mueller, Jutta L; Hirotani, Masako; Friederici, Angela D

2007-01-01

Background The present experiments were designed to test how the linguistic feature of case is processed in Japanese by native and non-native listeners. We used a miniature version of Japanese as a model to compare sentence comprehension mechanisms in native speakers and non-native learners who had received training until they had mastered the system. In the first experiment we auditorily presented native Japanese speakers with sentences containing incorrect double nominatives and incorrect double accusatives, and with correct sentences. In the second experiment we tested trained non-natives with the same material. Based on previous research in German we expected an N400-P600 biphasic ERP response with specific modulations depending on the violated case and whether the listeners were native or non-native. Results For native Japanese participants the general ERP response to the case violations was an N400-P600 pattern. Double accusatives led to an additional enhancement of the P600 amplitude. For the learners a native-like P600 was present for double accusatives and for double nominatives. The additional negativity, however, was present in learners only for double nominative violations, and it was characterized by a different topographical distribution. Conclusion The results indicate that native listeners use case markers for thematic as well as syntactic structure building during incremental sentence interpretation. The modulation of the P600 component for double accusatives possibly reflects case specific syntactic restrictions in Japanese. For adult language learners later processes, as reflected in the P600, seem to be more native-like compared to earlier processes. The anterior distribution of the negativity and its selective emergence for canonical sentences were taken to suggest that the non-native learners resorted to a rather formal processing strategy whereby they relied to a large degree on the phonologically salient nominative case marker. PMID:17331265

A Probabilistic Approach to Model Update

NASA Technical Reports Server (NTRS)

Horta, Lucas G.; Reaves, Mercedes C.; Voracek, David F.

2001-01-01

Finite element models are often developed for load validation, structural certification, response predictions, and to study alternate design concepts. In rare occasions, models developed with a nominal set of parameters agree with experimental data without the need to update parameter values. Today, model updating is generally heuristic and often performed by a skilled analyst with in-depth understanding of the model assumptions. Parameter uncertainties play a key role in understanding the model update problem and therefore probabilistic analysis tools, developed for reliability and risk analysis, may be used to incorporate uncertainty in the analysis. In this work, probability analysis (PA) tools are used to aid the parameter update task using experimental data and some basic knowledge of potential error sources. Discussed here is the first application of PA tools to update parameters of a finite element model for a composite wing structure. Static deflection data at six locations are used to update five parameters. It is shown that while prediction of individual response values may not be matched identically, the system response is significantly improved with moderate changes in parameter values.

A Vehicle Management End-to-End Testing and Analysis Platform for Validation of Mission and Fault Management Algorithms to Reduce Risk for NASA's Space Launch System

NASA Technical Reports Server (NTRS)

Trevino, Luis; Johnson, Stephen B.; Patterson, Jonathan; Teare, David

2015-01-01

The development of the Space Launch System (SLS) launch vehicle requires cross discipline teams with extensive knowledge of launch vehicle subsystems, information theory, and autonomous algorithms dealing with all operations from pre-launch through on orbit operations. The characteristics of these systems must be matched with the autonomous algorithm monitoring and mitigation capabilities for accurate control and response to abnormal conditions throughout all vehicle mission flight phases, including precipitating safing actions and crew aborts. This presents a large complex systems engineering challenge being addressed in part by focusing on the specific subsystems handling of off-nominal mission and fault tolerance. Using traditional model based system and software engineering design principles from the Unified Modeling Language (UML), the Mission and Fault Management (M&FM) algorithms are crafted and vetted in specialized Integrated Development Teams composed of multiple development disciplines. NASA also has formed an M&FM team for addressing fault management early in the development lifecycle. This team has developed a dedicated Vehicle Management End-to-End Testbed (VMET) that integrates specific M&FM algorithms, specialized nominal and off-nominal test cases, and vendor-supplied physics-based launch vehicle subsystem models. The flexibility of VMET enables thorough testing of the M&FM algorithms by providing configurable suites of both nominal and off-nominal test cases to validate the algorithms utilizing actual subsystem models. The intent is to validate the algorithms and substantiate them with performance baselines for each of the vehicle subsystems in an independent platform exterior to flight software test processes. In any software development process there is inherent risk in the interpretation and implementation of concepts into software through requirements and test processes. Risk reduction is addressed by working with other organizations such as S&MA, Structures and Environments, GNC, Orion, the Crew Office, Flight Operations, and Ground Operations by assessing performance of the M&FM algorithms in terms of their ability to reduce Loss of Mission and Loss of Crew probabilities. In addition, through state machine and diagnostic modeling, analysis efforts investigate a broader suite of failure effects and detection and responses that can be tested in VMET and confirm that responses do not create additional risks or cause undesired states through interactive dynamic effects with other algorithms and systems. VMET further contributes to risk reduction by prototyping and exercising the M&FM algorithms early in their implementation and without any inherent hindrances such as meeting FSW processor scheduling constraints due to their target platform - ARINC 653 partitioned OS, resource limitations, and other factors related to integration with other subsystems not directly involved with M&FM. The plan for VMET encompasses testing the original M&FM algorithms coded in the same C++ language and state machine architectural concepts as that used by Flight Software. This enables the development of performance standards and test cases to characterize the M&FM algorithms and sets a benchmark from which to measure the effectiveness of M&FM algorithms performance in the FSW development and test processes. This paper is outlined in a systematic fashion analogous to a lifecycle process flow for engineering development of algorithms into software and testing. Section I describes the NASA SLS M&FM context, presenting the current infrastructure, leading principles, methods, and participants. Section II defines the testing philosophy of the M&FM algorithms as related to VMET followed by section III, which presents the modeling methods of the algorithms to be tested and validated in VMET. Its details are then further presented in section IV followed by Section V presenting integration, test status, and state analysis. Finally, section VI addresses the summary and forward directions followed by the appendices presenting relevant information on terminology and documentation.

Triboluminescence from Pharmaceutical Formulations.

PubMed

Smith, Casey J; Griffin, Scott R; Eakins, Gregory S; Deng, Fengyuan; White, Julia K; Thirunahari, Satyanarayana; Ramakrishnan, Srividya; Sangupta, Atanu; Zhang, Siwei; Novak, Julie; Liu, Zhen; Rhodes, Timothy; Simpson, Garth J

2018-06-05

Triboluminescence (TL) is shown to enable selective detection of trace crystallinity within nominally amorphous solid dispersions (ASDs). ASDs are increasingly used for the preparation of pharmaceutical formulations, the physical stability of which can be negatively impacted by trace crystallinity introduced during manufacturing or storage. In the present study, TL measurements of a model ASD consisting of griseofulvin in polyethylene glycol produced limits of detection of 140 ppm. Separate studies of the particle size dependence of sucrose crystals and the dependence on polymorphism in clopidogrel bisulfate particles are both consistent with a mechanism for TL closely linked to the piezoelectric response of the crystalline fraction. Whereas disordered polymeric materials cannot support piezoelectric activity, molecular crystals produced from homochiral molecules adopt crystal structures that are overwhelmingly symmetry-allowed for piezoelectricity. Consequently, TL may provide a broadly applicable and simple experimental route for sensitive detection of trace crystallinity within nominally amorphous materials.

Three essays on monetary policy responses to oil price shocks

NASA Astrophysics Data System (ADS)

Plante, Michael

This dissertation contains three chapters which explore the question of how monetary policy should respond to changes in the price of oil. Each chapter explores the question from the perspective of a different economic environment. The first chapter examines welfare maximizing optimal monetary policy in a closed economy New Keynesian model that is extended to include household and firm demand for oil products, sticky wages, and capital accumulation. When households and firms demand oil products a natural difference arises between the Consumer Price Index (CPI), the core CPI, and the GDP deflator. I show that when nominal wages are flexible then the optimal policy places a heavy emphasis on stabilizing the inflation rate of the core CPI. If aggregate nominal wages are sticky then the central bank should focus on stabilizing some combination of core inflation and nominal wage inflation. Under no case examined is it optimal to stabilize either GDP deflator or CPI inflation. The second chapter examines monetary policy responses to oil price shocks in a small open economy with traded and non-traded goods. Oil and labor are used to produce the traded and non-traded goods and prices are sticky in the non-traded sector. I show analytically that the ratio of the oil and labor cost shares in the traded and non-traded sectors is crucial for determining the dynamic behavior of many macroeconomic variables after a rise in the price of oil. A policy of fixed exchange rates can produce higher or lower inflation in the non-traded sector depending upon the ratio. Likewise, a policy that stabilizes the inflation rate of prices in the non-traded sector can cause the nominal exchange rate to appreciate or depreciate. For the proper calibration, a policy that stabilizes core inflation produces results very close to the one that stabilizes non-traded inflation. Analytical results show that the fixed exchange rate always produces a unique solution. The policy of stabilizing non-traded inflation produces a unique solution so long as the nominal interest rate is raised more than one for one with increases in non-traded inflation. A policy of stabilizing core inflation, however, produces a unique solution only if the response is greater than one for one and less then one divided by one minus the share of the non-traded good in the CPI. In the third chapter I consider monetary and fiscal policy responses to oil price shocks in a low income oil importing country. The model used in this chapter differs from the model in the second chapter in that there is currency substitution, household demand for oil products, and a potential subsidy on the purchase of oil products by households. I examine the dynamic properties and the welfare implications of a set of inflation targeting policies and a group of policies that subsidize the price of oil and finance the subsidy through a combination of raising lump sum taxes and printing money. The dynamic properties of the inflation targeting policies are similar in many regards to those in the second chapter as the key assumptions driving the results are the same in the two models. For the policies which subsidize the price of oil I show that both the choice to have the subsidy and how to finance it matter a great deal for the behavior of the macroeconomic variables. In terms of welfare, for most calibrations there are only minor differences between the inflation targeting polices, the policy with a subsidy funded by lump sum taxes, and the baseline policy with no subsidy. The policy with a subsidy financed by the inflation tax generally causes significant welfare losses compared to the policy with no pass through.

Multispectral scanner flight model (F-1) radiometric calibration and alignment handbook

NASA Technical Reports Server (NTRS)

1981-01-01

This handbook on the calibration of the MSS-D flight model (F-1) provides both the relevant data and a summary description of how the data were obtained for the system radiometric calibration, system relative spectral response, and the filter response characteristics for all 24 channels of the four band MSS-D F-1 scanner. The calibration test procedure and resulting test data required to establish the reference light levels of the MSS-D internal calibration system are discussed. The final set of data ("nominal" calibration wedges for all 24 channels) for the internal calibration system is given. The system relative spectral response measurements for all 24 channels of MSS-D F-1 are included. These data are the spectral response of the complete scanner, which are the composite of the spectral responses of the scan mirror primary and secondary telescope mirrors, fiber optics, optical filters, and detectors. Unit level test data on the measurements of the individual channel optical transmission filters are provided. Measured performance is compared to specification values.

Response of CMS avalanche photo-diodes to low energy neutrons

NASA Astrophysics Data System (ADS)

Brown, R. M.; Deiters, K.; Ingram, Q.; Renker, D.

2012-12-01

The response of the Avalanche Photo-diodes (APDs) installed in the CMS detector at the LHC to neutrons from 241AmBe and 252Cf sources is reported. Signals in size equivalent to those of up to 106 photo-electrons with the nominal APD gain are observed. Measurements with an APD with the protective epoxy coating removed and with the source placed behind the APD show that there is an important response due to recoil protons from neutron interactions with the hydrogen in the epoxy, in addition to signals from neutron interactions with the silicon of the diode. The effective gain of these signals is much smaller than the diode's nominal gain.

Goal-Function Tree Modeling for Systems Engineering and Fault Management

NASA Technical Reports Server (NTRS)

Johnson, Stephen B.; Breckenridge, Jonathan T.

2013-01-01

This paper describes a new representation that enables rigorous definition and decomposition of both nominal and off-nominal system goals and functions: the Goal-Function Tree (GFT). GFTs extend the concept and process of functional decomposition, utilizing state variables as a key mechanism to ensure physical and logical consistency and completeness of the decomposition of goals (requirements) and functions, and enabling full and complete traceabilitiy to the design. The GFT also provides for means to define and represent off-nominal goals and functions that are activated when the system's nominal goals are not met. The physical accuracy of the GFT, and its ability to represent both nominal and off-nominal goals enable the GFT to be used for various analyses of the system, including assessments of the completeness and traceability of system goals and functions, the coverage of fault management failure detections, and definition of system failure scenarios.

Using Nominal Group Technique to Develop a Consensus Derived Model for Peer Review of Teaching across a Multi-School Faculty

ERIC Educational Resources Information Center

Burrows, Tracy; Findlay, Naomi; Killen, Chloe; Dempsey, Shane E.; Hunter, Sharyn; Chiarelli, Pauline; Snodgrass, Suzanne

2011-01-01

This paper describes the development of a peer review of teaching model for the Faculty of Health at the University of Newcastle, Australia. The process involved using the nominal group technique to engage Faculty academic staff to consider seven key decision points that informed the development of the peer review of teaching model. Use of the…

Orion Burn Management, Nominal and Response to Failures

NASA Technical Reports Server (NTRS)

Odegard, Ryan; Goodman, John L.; Barrett, Charles P.; Pohlkamp, Kara; Robinson, Shane

2016-01-01

An approach for managing Orion on-orbit burn execution is described for nominal and failure response scenarios. The burn management strategy for Orion takes into account per-burn variations in targeting, timing, and execution; crew and ground operator intervention and overrides; defined burn failure triggers and responses; and corresponding on-board software sequencing functionality. Burn-to- burn variations are managed through the identification of specific parameters that may be updated for each progressive burn. Failure triggers and automatic responses during the burn timeframe are defined to provide safety for the crew in the case of vehicle failures, along with override capabilities to ensure operational control of the vehicle. On-board sequencing software provides the timeline coordination for performing the required activities related to targeting, burn execution, and responding to burn failures.

Galileo probe forebody thermal protection - Benchmark heating environment calculations

NASA Technical Reports Server (NTRS)

Balakrishnan, A.; Nicolet, W. E.

1981-01-01

Solutions are presented for the aerothermal heating environment for the forebody heatshield of candidate Galileo probe. Entry into both the nominal and cool-heavy model atmospheres were considered. Solutions were obtained for the candidate heavy probe with a weight of 310 kg and a lighter probe with a weight of 290 kg. In the flowfield analysis, a finite difference procedure was employed to obtain benchmark predictions of pressure, radiative and convective heating rates, and the steady-state wall blowing rates. Calculated heating rates for entry into the cool-heavy model atmosphere were about 60 percent higher than those predicted for the entry into the nominal atmosphere. The total mass lost for entry into the cool-heavy model atmosphere was about 146 kg and the mass lost for entry into the nominal model atmosphere was about 101 kg.

Nominations for Sale1

PubMed Central

Console-Battilana, Silvia; Shepsle, Kenneth A.

2009-01-01

Models of nomination politics in the US often find “gridlock” in equilibrium because of the super-majority requirement in the Senate for the confirmation of presidential nominees. A blocking coalition often prefers to defeat any nominee. Yet empirically nominations are successful. In the present paper we explore the possibility that senators can be induced to vote contrary to their nominal (gridlock-producing) preferences through contributions from the president and/or lobbyists, thus breaking the gridlock and confirming the nominee. We model contributions by the president and lobbyists according to whether payment schedules are conditioned on the entire voting profile, the vote of a senator, or the outcome. We analyze several extensions to our baseline approach, including the possibility that lobbyists may find it more productive to offer inducements to the president in order to affect his proposal behavior, rather than trying to induce senators to vote for or against a given nominee. PMID:20011612

Using Dispersed Modes During Model Correlation

NASA Technical Reports Server (NTRS)

Stewart, Eric C.; Hathcock, Megan L.

2017-01-01

The model correlation process for the modal characteristics of a launch vehicle is well established. After a test, parameters within the nominal model are adjusted to reflect structural dynamics revealed during testing. However, a full model correlation process for a complex structure can take months of man-hours and many computational resources. If the analyst only has weeks, or even days, of time in which to correlate the nominal model to the experimental results, then the traditional correlation process is not suitable. This paper describes using model dispersions to assist the model correlation process and decrease the overall cost of the process. The process creates thousands of model dispersions from the nominal model prior to the test and then compares each of them to the test data. Using mode shape and frequency error metrics, one dispersion is selected as the best match to the test data. This dispersion is further improved by using a commercial model correlation software. In the three examples shown in this paper, this dispersion based model correlation process performs well when compared to models correlated using traditional techniques and saves time in the post-test analysis.

78 FR 57868 - Nominations to the Report on Carcinogens; Request for Information

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-20

..., P.O. Box 12233, MD K2-14, Research Triangle Park, NC 27709; telephone (919) 316-4637; FAX: (301) 480... * Nominations to the RoC may seek to list a new substance in the report, reclassify the listing status of a... part of the U.S. Government to provide support for any ideas identified in response to it. Please note...

GEE-Smoothing Spline in Semiparametric Model with Correlated Nominal Data

NASA Astrophysics Data System (ADS)

Ibrahim, Noor Akma; Suliadi

2010-11-01

In this paper we propose GEE-Smoothing spline in the estimation of semiparametric models with correlated nominal data. The method can be seen as an extension of parametric generalized estimating equation to semiparametric models. The nonparametric component is estimated using smoothing spline specifically the natural cubic spline. We use profile algorithm in the estimation of both parametric and nonparametric components. The properties of the estimators are evaluated using simulation studies.

The human as a detector of changes in variance and bandwidth

NASA Technical Reports Server (NTRS)

Curry, R. E.; Govindaraj, T.

1977-01-01

The detection of changes in random process variance and bandwidth was studied. Psychophysical thresholds for these two parameters were determined using an adaptive staircase technique for second order random processes at two nominal periods (1 and 3 seconds) and damping ratios (0.2 and 0.707). Thresholds for bandwidth changes were approximately 9% of nominal except for the (3sec,0.2) process which yielded thresholds of 12%. Variance thresholds averaged 17% of nominal except for the (3sec,0.2) process in which they were 32%. Detection times for suprathreshold changes in the parameters may be roughly described by the changes in RMS velocity of the process. A more complex model is presented which consists of a Kalman filter designed for the nominal process using velocity as the input, and a modified Wald sequential test for changes in the variance of the residual. The model predictions agree moderately well with the experimental data. Models using heuristics, e.g. level crossing counters, were also examined and are found to be descriptive but do not afford the unification of the Kalman filter/sequential test model used for changes in mean.

The Influence of Mesh Density on the Impact Response of a Shuttle Leading-Edge Panel Finite Element Simulation

NASA Technical Reports Server (NTRS)

Jackson, Karen E.; Fasanella, Edwin L.; Lyle, Karen H.; Spellman, Regina L.

2004-01-01

A study was performed to examine the influence of varying mesh density on an LS-DYNA simulation of a rectangular-shaped foam projectile impacting the space shuttle leading edge Panel 6. The shuttle leading-edge panels are fabricated of reinforced carbon-carbon (RCC) material. During the study, nine cases were executed with all possible combinations of coarse, baseline, and fine meshes of the foam and panel. For each simulation, the same material properties and impact conditions were specified and only the mesh density was varied. In the baseline model, the shell elements representing the RCC panel are approximately 0.2-in. on edge, whereas the foam elements are about 0.5-in. on edge. The element nominal edge-length for the baseline panel was halved to create a fine panel (0.1-in. edge length) mesh and doubled to create a coarse panel (0.4-in. edge length) mesh. In addition, the element nominal edge-length of the baseline foam projectile was halved (0.25-in. edge length) to create a fine foam mesh and doubled (1.0- in. edge length) to create a coarse foam mesh. The initial impact velocity of the foam was 775 ft/s. The simulations were executed in LS-DYNA version 960 for 6 ms of simulation time. Contour plots of resultant panel displacement and effective stress in the foam were compared at five discrete time intervals. Also, time-history responses of internal and kinetic energy of the panel, kinetic and hourglass energy of the foam, and resultant contact force were plotted to determine the influence of mesh density. As a final comparison, the model with a fine panel and fine foam mesh was executed with slightly different material properties for the RCC. For this model, the average degraded properties of the RCC were replaced with the maximum degraded properties. Similar comparisons of panel and foam responses were made for the average and maximum degraded models.

On Impedance Spectroscopy of Supercapacitors

NASA Astrophysics Data System (ADS)

Uchaikin, V. V.; Sibatov, R. T.; Ambrozevich, A. S.

2016-10-01

Supercapacitors are often characterized by responses measured by methods of impedance spectroscopy. In the frequency domain these responses have the form of power-law functions or their linear combinations. The inverse Fourier transform leads to relaxation equations with integro-differential operators of fractional order under assumption that the frequency response is independent of the working voltage. To compare long-term relaxation kinetics predicted by these equations with the observed one, charging-discharging of supercapacitors (with nominal capacitances of 0.22, 0.47, and 1.0 F) have been studied by means of registration of the current response to a step voltage signal. It is established that the reaction of devices under study to variations of the charging regime disagrees with the model of a homogeneous linear response. It is demonstrated that relaxation is well described by a fractional stretched exponent.

Identification of cascade water tanks using a PWARX model

NASA Astrophysics Data System (ADS)

Mattsson, Per; Zachariah, Dave; Stoica, Petre

2018-06-01

In this paper we consider the identification of a discrete-time nonlinear dynamical model for a cascade water tank process. The proposed method starts with a nominal linear dynamical model of the system, and proceeds to model its prediction errors using a model that is piecewise affine in the data. As data is observed, the nominal model is refined into a piecewise ARX model which can capture a wide range of nonlinearities, such as the saturation in the cascade tanks. The proposed method uses a likelihood-based methodology which adaptively penalizes model complexity and directly leads to a computationally efficient implementation.

A Vehicle Management End-to-End Testing and Analysis Platform for Validation of Mission and Fault Management Algorithms to Reduce Risk for NASAs Space Launch System

NASA Technical Reports Server (NTRS)

Trevino, Luis; Johnson, Stephen B.; Patterson, Jonathan; Teare, David

2015-01-01

The engineering development of the National Aeronautics and Space Administration's (NASA) new Space Launch System (SLS) requires cross discipline teams with extensive knowledge of launch vehicle subsystems, information theory, and autonomous algorithms dealing with all operations from pre-launch through on orbit operations. The nominal and off-nominal characteristics of SLS's elements and subsystems must be understood and matched with the autonomous algorithm monitoring and mitigation capabilities for accurate control and response to abnormal conditions throughout all vehicle mission flight phases, including precipitating safing actions and crew aborts. This presents a large and complex systems engineering challenge, which is being addressed in part by focusing on the specific subsystems involved in the handling of off-nominal mission and fault tolerance with response management. Using traditional model-based system and software engineering design principles from the Unified Modeling Language (UML) and Systems Modeling Language (SysML), the Mission and Fault Management (M&FM) algorithms for the vehicle are crafted and vetted in Integrated Development Teams (IDTs) composed of multiple development disciplines such as Systems Engineering (SE), Flight Software (FSW), Safety and Mission Assurance (S&MA) and the major subsystems and vehicle elements such as Main Propulsion Systems (MPS), boosters, avionics, Guidance, Navigation, and Control (GNC), Thrust Vector Control (TVC), and liquid engines. These model-based algorithms and their development lifecycle from inception through FSW certification are an important focus of SLS's development effort to further ensure reliable detection and response to off-nominal vehicle states during all phases of vehicle operation from pre-launch through end of flight. To test and validate these M&FM algorithms a dedicated test-bed was developed for full Vehicle Management End-to-End Testing (VMET). For addressing fault management (FM) early in the development lifecycle for the SLS program, NASA formed the M&FM team as part of the Integrated Systems Health Management and Automation Branch under the Spacecraft Vehicle Systems Department at the Marshall Space Flight Center (MSFC). To support the development of the FM algorithms, the VMET developed by the M&FM team provides the ability to integrate the algorithms, perform test cases, and integrate vendor-supplied physics-based launch vehicle (LV) subsystem models. Additionally, the team has developed processes for implementing and validating the M&FM algorithms for concept validation and risk reduction. The flexibility of the VMET capabilities enables thorough testing of the M&FM algorithms by providing configurable suites of both nominal and off-nominal test cases to validate the developed algorithms utilizing actual subsystem models such as MPS, GNC, and others. One of the principal functions of VMET is to validate the M&FM algorithms and substantiate them with performance baselines for each of the target vehicle subsystems in an independent platform exterior to the flight software test and validation processes. In any software development process there is inherent risk in the interpretation and implementation of concepts from requirements and test cases into flight software compounded with potential human errors throughout the development and regression testing lifecycle. Risk reduction is addressed by the M&FM group but in particular by the Analysis Team working with other organizations such as S&MA, Structures and Environments, GNC, Orion, Crew Office, Flight Operations, and Ground Operations by assessing performance of the M&FM algorithms in terms of their ability to reduce Loss of Mission (LOM) and Loss of Crew (LOC) probabilities. In addition, through state machine and diagnostic modeling, analysis efforts investigate a broader suite of failure effects and associated detection and responses to be tested in VMET to ensure reliable failure detection, and confirm responses do not create additional risks or cause undesired states through interactive dynamic effects with other algorithms and systems. VMET further contributes to risk reduction by prototyping and exercising the M&FM algorithms early in their implementation and without any inherent hindrances such as meeting FSW processor scheduling constraints due to their target platform - the ARINC 6535-partitioned Operating System, resource limitations, and other factors related to integration with other subsystems not directly involved with M&FM such as telemetry packing and processing. The baseline plan for use of VMET encompasses testing the original M&FM algorithms coded in the same C++ language and state machine architectural concepts as that used by FSW. This enables the development of performance standards and test cases to characterize the M&FM algorithms and sets a benchmark from which to measure their effectiveness and performance in the exterior FSW development and test processes. This paper is outlined in a systematic fashion analogous to a lifecycle process flow for engineering development of algorithms into software and testing. Section I describes the NASA SLS M&FM context, presenting the current infrastructure, leading principles, methods, and participants. Section II defines the testing philosophy of the M&FM algorithms as related to VMET followed by section III, which presents the modeling methods of the algorithms to be tested and validated in VMET. Its details are then further presented in section IV followed by Section V presenting integration, test status, and state analysis. Finally, section VI addresses the summary and forward directions followed by the appendices presenting relevant information on terminology and documentation.

Effects of model aromatizable (17α-methyltestosterone) and non-aromatizable (5α-dihydrotestosterone) androgens on the adult mummichog (Fundulus heteroclitus) in a short-term reproductive endocrine bioassay.

PubMed

Rutherford, Robert; Lister, Andrea; Hewitt, L Mark; MacLatchy, Deborah

2015-04-01

Androgens originating from pulp mill processing, sewage treatment facilities and agricultural activities have the potential for discharge into aquatic receiving environments. To assess androgen effects on reproductive endocrine status in fish in estuarine environments, male and female adult northern mummichog (Fundulus heteroclitus macrolepidotus) were exposed to an aromatizable androgen (17α-methyltestosterone; MT) and a non-aromatizable androgen (5α-dihydrotestosterone; DHT) in a short-term reproductive endocrine bioassay. Fish were nominally exposed to 10 μg/L or 100 μg/L DHT, or 0.1 μg/L or 1 μg/L MT for 14 days during gonadal recrudescence. Actual concentrations of androgens, as measured by enzyme immunoassay (EIA), were 10-49% of nominal MT 0.1, 3-6% of nominal MT 1, 5-10% of nominal DHT 10 and 3-25% of nominal DHT 100. Female mummichog were impacted to a greater degree by androgen exposure, with increased plasma testosterone (T) at 100 μg/L DHT, depressed plasma 17β-estradiol (E2) at both DHT concentrations and at 1 μg/L MT, as well as depressed in vitro E2 at both MT concentrations and 100 μg/L DHT. Males had depressed plasma T in the 10 μg/L DHT treatment and depressed in vitro 11-ketotestosterone production for both MT concentrations and 10 μg/L DHT. Ovarian aromatase gene expression was induced in females exposed to 1 μg/L MT. DHT at 100 μg/L increased hepatic vitellogenin-1 (VTG1) expression in males and depressed VTG1 expression in females. The range of responses between sexes and among species provides evidence for modes of actions and potential impacts of androgens in aquatic receiving environments. Copyright © 2015 Elsevier Inc. All rights reserved.

Robust linear parameter-varying control of blood pressure using vasoactive drugs

NASA Astrophysics Data System (ADS)

Luspay, Tamas; Grigoriadis, Karolos

2015-10-01

Resuscitation of emergency care patients requires fast restoration of blood pressure to a target value to achieve hemodynamic stability and vital organ perfusion. A robust control design methodology is presented in this paper for regulating the blood pressure of hypotensive patients by means of the closed-loop administration of vasoactive drugs. To this end, a dynamic first-order delay model is utilised to describe the vasoactive drug response with varying parameters that represent intra-patient and inter-patient variability. The proposed framework consists of two components: first, an online model parameter estimation is carried out using a multiple-model extended Kalman-filter. Second, the estimated model parameters are used for continuously scheduling a robust linear parameter-varying (LPV) controller. The closed-loop behaviour is characterised by parameter-varying dynamic weights designed to regulate the mean arterial pressure to a target value. Experimental data of blood pressure response of anesthetised pigs to phenylephrine injection are used for validating the LPV blood pressure models. Simulation studies are provided to validate the online model estimation and the LPV blood pressure control using phenylephrine drug injection models representing patients showing sensitive, nominal and insensitive response to the drug.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Jin; Zhang, Yingchen; Krad, Ibrahim

Power system frequency needs to be maintained close to its nominal value at all times to avoid machine damage, under-frequency load-shedding and even blackouts. Adequate primary frequency response and secondary frequency response are the primary forces to correct an energy imbalance at the second to minute level. As wind energy becomes a larger portion of the world's energy portfolio, there are greater oppotunities for wind to provide frequency response services. This paper addresses one area of frequency control that has been missing in previous work - the reliabilty impacts and interactions between primary and secondary frequency control. The lack ofmore » a commercially available tools to simulate the interaction of these two responses has limited the energy industry's understanding of when the depletion of primary control reserve will impact the performance of secondary conrol response or vice versa. To investigate this issue, in this paper we develop a multi-area frequency response integration model with combined primary and secondary frequency control capabilities.« less

Abstract Model of the SATS Concept of Operations: Initial Results and Recommendations

NASA Technical Reports Server (NTRS)

Dowek, Gilles; Munoz, Cesar; Carreno, Victor A.

2004-01-01

An abstract mathematical model of the concept of operations for the Small Aircraft Transportation System (SATS) is presented. The Concept of Operations consist of several procedures that describe nominal operations for SATS, Several safety properties of the system are proven using formal techniques. The final goal of the verification effort is to show that under nominal operations, aircraft are safely separated. The abstract model was written and formally verified in the Prototype Verification System (PVS).

Practice reduces task relevant variance modulation and forms nominal trajectory

NASA Astrophysics Data System (ADS)

Osu, Rieko; Morishige, Ken-Ichi; Nakanishi, Jun; Miyamoto, Hiroyuki; Kawato, Mitsuo

2015-12-01

Humans are capable of achieving complex tasks with redundant degrees of freedom. Much attention has been paid to task relevant variance modulation as an indication of online feedback control strategies to cope with motor variability. Meanwhile, it has been discussed that the brain learns internal models of environments to realize feedforward control with nominal trajectories. Here we examined trajectory variance in both spatial and temporal domains to elucidate the relative contribution of these control schemas. We asked subjects to learn reaching movements with multiple via-points, and found that hand trajectories converged to stereotyped trajectories with the reduction of task relevant variance modulation as learning proceeded. Furthermore, variance reduction was not always associated with task constraints but was highly correlated with the velocity profile. A model assuming noise both on the nominal trajectory and motor command was able to reproduce the observed variance modulation, supporting an expression of nominal trajectories in the brain. The learning-related decrease in task-relevant modulation revealed a reduction in the influence of optimal feedback around the task constraints. After practice, the major part of computation seems to be taken over by the feedforward controller around the nominal trajectory with feedback added only when it becomes necessary.

Planetary Suit Hip Bearing Model for Predicting Design vs. Performance

NASA Technical Reports Server (NTRS)

Cowley, Matthew S.; Margerum, Sarah; Harvil, Lauren; Rajulu, Sudhakar

2011-01-01

Designing a planetary suit is very complex and often requires difficult trade-offs between performance, cost, mass, and system complexity. In order to verifying that new suit designs meet requirements, full prototypes must eventually be built and tested with human subjects. Using computer models early in the design phase of new hardware development can be advantageous, allowing virtual prototyping to take place. Having easily modifiable models of the suit hard sections may reduce the time it takes to make changes to the hardware designs and then to understand their impact on suit and human performance. A virtual design environment gives designers the ability to think outside the box and exhaust design possibilities before building and testing physical prototypes with human subjects. Reductions in prototyping and testing may eventually reduce development costs. This study is an attempt to develop computer models of the hard components of the suit with known physical characteristics, supplemented with human subject performance data. Objectives: The primary objective was to develop an articulating solid model of the Mark III hip bearings to be used for evaluating suit design performance of the hip joint. Methods: Solid models of a planetary prototype (Mark III) suit s hip bearings and brief section were reverse-engineered from the prototype. The performance of the models was then compared by evaluating the mobility performance differences between the nominal hardware configuration and hardware modifications. This was accomplished by gathering data from specific suited tasks. Subjects performed maximum flexion and abduction tasks while in a nominal suit bearing configuration and in three off-nominal configurations. Performance data for the hip were recorded using state-of-the-art motion capture technology. Results: The results demonstrate that solid models of planetary suit hard segments for use as a performance design tool is feasible. From a general trend perspective, the suited performance trends were comparable between the model and the suited subjects. With the three off-nominal bearing configurations compared to the nominal bearing configurations, human subjects showed decreases in hip flexion of 64%, 6%, and 13% and in hip abduction of 59%, 2%, and 20%. Likewise the solid model showed decreases in hip flexion of 58%, 1%, and 25% and in hip abduction of 56%, 0%, and 30%, under the same condition changes from the nominal configuration. Differences seen between the model predictions and the human subject performance data could be attributed to the model lacking dynamic elements and performing kinematic analysis only, the level of fit of the subjects with the suit, the levels of the subject s suit experience.

An introduction to mixture item response theory models.

PubMed

De Ayala, R J; Santiago, S Y

2017-02-01

Mixture item response theory (IRT) allows one to address situations that involve a mixture of latent subpopulations that are qualitatively different but within which a measurement model based on a continuous latent variable holds. In this modeling framework, one can characterize students by both their location on a continuous latent variable as well as by their latent class membership. For example, in a study of risky youth behavior this approach would make it possible to estimate an individual's propensity to engage in risky youth behavior (i.e., on a continuous scale) and to use these estimates to identify youth who might be at the greatest risk given their class membership. Mixture IRT can be used with binary response data (e.g., true/false, agree/disagree, endorsement/not endorsement, correct/incorrect, presence/absence of a behavior), Likert response scales, partial correct scoring, nominal scales, or rating scales. In the following, we present mixture IRT modeling and two examples of its use. Data needed to reproduce analyses in this article are available as supplemental online materials at http://dx.doi.org/10.1016/j.jsp.2016.01.002. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

A Model-Based Anomaly Detection Approach for Analyzing Streaming Aircraft Engine Measurement Data

NASA Technical Reports Server (NTRS)

Simon, Donald L.; Rinehart, Aidan W.

2014-01-01

This paper presents a model-based anomaly detection architecture designed for analyzing streaming transient aircraft engine measurement data. The technique calculates and monitors residuals between sensed engine outputs and model predicted outputs for anomaly detection purposes. Pivotal to the performance of this technique is the ability to construct a model that accurately reflects the nominal operating performance of the engine. The dynamic model applied in the architecture is a piecewise linear design comprising steady-state trim points and dynamic state space matrices. A simple curve-fitting technique for updating the model trim point information based on steadystate information extracted from available nominal engine measurement data is presented. Results from the application of the model-based approach for processing actual engine test data are shown. These include both nominal fault-free test case data and seeded fault test case data. The results indicate that the updates applied to improve the model trim point information also improve anomaly detection performance. Recommendations for follow-on enhancements to the technique are also presented and discussed.

A Model-Based Anomaly Detection Approach for Analyzing Streaming Aircraft Engine Measurement Data

NASA Technical Reports Server (NTRS)

Simon, Donald L.; Rinehart, Aidan Walker

2015-01-01

This paper presents a model-based anomaly detection architecture designed for analyzing streaming transient aircraft engine measurement data. The technique calculates and monitors residuals between sensed engine outputs and model predicted outputs for anomaly detection purposes. Pivotal to the performance of this technique is the ability to construct a model that accurately reflects the nominal operating performance of the engine. The dynamic model applied in the architecture is a piecewise linear design comprising steady-state trim points and dynamic state space matrices. A simple curve-fitting technique for updating the model trim point information based on steadystate information extracted from available nominal engine measurement data is presented. Results from the application of the model-based approach for processing actual engine test data are shown. These include both nominal fault-free test case data and seeded fault test case data. The results indicate that the updates applied to improve the model trim point information also improve anomaly detection performance. Recommendations for follow-on enhancements to the technique are also presented and discussed.

Quantification of the effect of cross-shear and applied nominal contact pressure on the wear of moderately cross-linked polyethylene.

PubMed

Abdelgaied, Abdellatif; Brockett, Claire L; Liu, Feng; Jennings, Louise M; Fisher, John; Jin, Zhongmin

2013-01-01

Polyethylene wear is a great concern in total joint replacement. It is now considered a major limiting factor to the long life of such prostheses. Cross-linking has been introduced to reduce the wear of ultra-high-molecular-weight polyethylene (UHMWPE). Computational models have been used extensively for wear prediction and optimization of artificial knee designs. However, in order to be independent and have general applicability and predictability, computational wear models should be based on inputs from independent experimentally determined wear parameters (wear factors or wear coefficients). The objective of this study was to investigate moderately cross-linked UHMWPE, using a multidirectional pin-on-plate wear test machine, under a wide range of applied nominal contact pressure (from 1 to 11 MPa) and under five different kinematic inputs, varying from a purely linear track to a maximum rotation of +/- 55 degrees. A computational model, based on a direct simulation of the multidirectional pin-on-plate wear tester, was developed to quantify the degree of cross-shear (CS) of the polyethylene pins articulating against the metallic plates. The moderately cross-linked UHMWPE showed wear factors less than half of that reported in the literature for, the conventional UHMWPE, under the same loading and kinematic inputs. In addition, under high applied nominal contact stress, the moderately crosslinked UHMWPE wear showed lower dependence on the degree of CS compared to that under low applied nominal contact stress. The calculated wear coefficients were found to be independent of the applied nominal contact stress, in contrast to the wear factors that were shown to be highly pressure dependent. This study provided independent wear data for inputs into computational models for moderately cross-linked polyethylene and supported the application of wear coefficient-based computational wear models.

Towards Validation of an Adaptive Flight Control Simulation Using Statistical Emulation

NASA Technical Reports Server (NTRS)

He, Yuning; Lee, Herbert K. H.; Davies, Misty D.

2012-01-01

Traditional validation of flight control systems is based primarily upon empirical testing. Empirical testing is sufficient for simple systems in which a.) the behavior is approximately linear and b.) humans are in-the-loop and responsible for off-nominal flight regimes. A different possible concept of operation is to use adaptive flight control systems with online learning neural networks (OLNNs) in combination with a human pilot for off-nominal flight behavior (such as when a plane has been damaged). Validating these systems is difficult because the controller is changing during the flight in a nonlinear way, and because the pilot and the control system have the potential to co-adapt in adverse ways traditional empirical methods are unlikely to provide any guarantees in this case. Additionally, the time it takes to find unsafe regions within the flight envelope using empirical testing means that the time between adaptive controller design iterations is large. This paper describes a new concept for validating adaptive control systems using methods based on Bayesian statistics. This validation framework allows the analyst to build nonlinear models with modal behavior, and to have an uncertainty estimate for the difference between the behaviors of the model and system under test.

When Empathy Matters: The Role of Sex and Empathy in Close Friendships.

PubMed

Ciarrochi, Joseph; Parker, Philip D; Sahdra, Baljinder K; Kashdan, Todd B; Kiuru, Noona; Conigrave, James

2017-08-01

Based on prior theory and research (Ciarrochi & Heaven, 2009; Eagly & Wood, 1999), we hypothesized that the link between empathy and friendship would be moderated by sex: Girls will nominate empathic boys as friends, whereas boys will not tend to nominate empathic girls. We collected measures of empathy, friendship social support, and close friendship nominations in grade 10 across 1,970 students in 16 schools (M age  = 15.70, SD = .44; males = 993, females = 977). Multilevel models revealed that boys high in cognitive empathy attracted an average of 1.8 more girl friendship nominations than did their low empathy counterparts, whereas empathic girls did not attract a greater number of opposite-sex friends. In addition, the more friendship nominations a boy received from either boys or girls, the more they felt supported by their friends; the number of friendship nominations received by girls, in contrast, had no effect on their felt support by friends. Regardless of the quantity of friendship nominations, empathy was linked to more supportive friendships for both males and females. These results inform a contextual understanding of the role of empathy in selecting and maintaining friendships. © 2016 Wiley Periodicals, Inc.

A Genesis breakup and burnup analysis in off-nominal Earth return and atmospheric entry

NASA Technical Reports Server (NTRS)

Salama, Ahmed; Ling, Lisa; McRonald, Angus

2005-01-01

The Genesis project conducted a detailed breakup/burnup analysis before the Earth return to determine if any spacecraft component could survive and reach the ground intact in case of an off-nominal entry. In addition, an independent JPL team was chartered with the responsibility of analyzing several definitive breakup scenarios to verify the official project analysis. This paper presents the analysis and results of this independent team.

Testing the Agreement/Tense Omission Model: Why the Data on Children's Use of Non-Nominative 3psg Subjects Count against the ATOM

ERIC Educational Resources Information Center

Pine, Julian M.; Rowland, Caroline F.; Lieven, Elena V. M.; Theakston, Anna L.

2005-01-01

One of the most influential recent accounts of pronoun case-marking errors in young children's speech is Schutze & Wexler's (1996) Agreement/Tense Omission Model (ATOM). The ATOM predicts that the rate of agreeing verbs with non-nominative subjects will be so low that such errors can be reasonably disregarded as noise in the data. The present…

ACOSS Eight (Active Control of Space Structures), Phase 2

DTIC Science & Technology

1981-09-01

A-2 A-2 Nominal Model - Equipment Section and Solar Panels ....... A-3 A-3 Nominal Model - Upper Support .-uss ...... ............ A-4 A...sensitivity analysis technique ef selecting critical system parameters is applied tc the Diaper tetrahedral truss structure (See Section 4-2...and solar panels are omitted. The precision section is mounted on isolators to inertially r•" I fixed rigid support. The mode frequencies of this

K-ε Turbulence Model Parameter Estimates Using an Approximate Self-similar Jet-in-Crossflow Solution

DOE PAGES

DeChant, Lawrence; Ray, Jaideep; Lefantzi, Sophia; ...

2017-06-09

The k-ε turbulence model has been described as perhaps “the most widely used complete turbulence model.” This family of heuristic Reynolds Averaged Navier-Stokes (RANS) turbulence closures is supported by a suite of model parameters that have been estimated by demanding the satisfaction of well-established canonical flows such as homogeneous shear flow, log-law behavior, etc. While this procedure does yield a set of so-called nominal parameters, it is abundantly clear that they do not provide a universally satisfactory turbulence model that is capable of simulating complex flows. Recent work on the Bayesian calibration of the k-ε model using jet-in-crossflow wind tunnelmore » data has yielded parameter estimates that are far more predictive than nominal parameter values. In this paper, we develop a self-similar asymptotic solution for axisymmetric jet-in-crossflow interactions and derive analytical estimates of the parameters that were inferred using Bayesian calibration. The self-similar method utilizes a near field approach to estimate the turbulence model parameters while retaining the classical far-field scaling to model flow field quantities. Our parameter values are seen to be far more predictive than the nominal values, as checked using RANS simulations and experimental measurements. They are also closer to the Bayesian estimates than the nominal parameters. A traditional simplified jet trajectory model is explicitly related to the turbulence model parameters and is shown to yield good agreement with measurement when utilizing the analytical derived turbulence model coefficients. Finally, the close agreement between the turbulence model coefficients obtained via Bayesian calibration and the analytically estimated coefficients derived in this paper is consistent with the contention that the Bayesian calibration approach is firmly rooted in the underlying physical description.« less

Optimizing multi-dimensional high throughput screening using zebrafish

PubMed Central

Truong, Lisa; Bugel, Sean M.; Chlebowski, Anna; Usenko, Crystal Y.; Simonich, Michael T.; Massey Simonich, Staci L.; Tanguay, Robert L.

2016-01-01

The use of zebrafish for high throughput screening (HTS) for chemical bioactivity assessments is becoming routine in the fields of drug discovery and toxicology. Here we report current recommendations from our experiences in zebrafish HTS. We compared the effects of different high throughput chemical delivery methods on nominal water concentration, chemical sorption to multi-well polystyrene plates, transcription responses, and resulting whole animal responses. We demonstrate that digital dispensing consistently yields higher data quality and reproducibility compared to standard plastic tip-based liquid handling. Additionally, we illustrate the challenges in using this sensitive model for chemical assessment when test chemicals have trace impurities. Adaptation of these better practices for zebrafish HTS should increase reproducibility across laboratories. PMID:27453428

Assessing Interval Estimation Methods for Hill Model ...

EPA Pesticide Factsheets

The Hill model of concentration-response is ubiquitous in toxicology, perhaps because its parameters directly relate to biologically significant metrics of toxicity such as efficacy and potency. Point estimates of these parameters obtained through least squares regression or maximum likelihood are commonly used in high-throughput risk assessment, but such estimates typically fail to include reliable information concerning confidence in (or precision of) the estimates. To address this issue, we examined methods for assessing uncertainty in Hill model parameter estimates derived from concentration-response data. In particular, using a sample of ToxCast concentration-response data sets, we applied four methods for obtaining interval estimates that are based on asymptotic theory, bootstrapping (two varieties), and Bayesian parameter estimation, and then compared the results. These interval estimation methods generally did not agree, so we devised a simulation study to assess their relative performance. We generated simulated data by constructing four statistical error models capable of producing concentration-response data sets comparable to those observed in ToxCast. We then applied the four interval estimation methods to the simulated data and compared the actual coverage of the interval estimates to the nominal coverage (e.g., 95%) in order to quantify performance of each of the methods in a variety of cases (i.e., different values of the true Hill model paramet

77 FR 20396 - Request for Nominations of Candidates to the EPA's Clean Air Scientific Advisory Committee (CASAC...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-04

... sciences; risk assessment; and statistics. For further information about the RAC membership appointment... decision sciences; and modeling and statistics. The SAB Staff Office is especially interested in scientists... ENVIRONMENTAL PROTECTION AGENCY [FRL-9656-1] Request for Nominations of Candidates to the EPA's...

“Elegant Tool” Delivers Genome-Level Science for Electrolytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keith Arterburn

Now, a ‘disruptive, virtual scientific simulation tool’ delivers a new, genome-level investigation for electrolytes to develop better, more efficient batteries. Dr. Kevin Gering, an Idaho National Laboratory researcher, has developed the Advanced Electrolyte Model (AEM), a copyrighted molecular-based simulation tool that has been scientifically proven and validated using at least a dozen ‘real-world’ physical metrics. Nominated for the 2014 international R&D 100 Award, AEM revolutionizes electrolyte materials selection, optimizing combinations and key design elements to make battery design and experimentation quick, accurate and responsive to specific needs.

Modeling the Proton Radiation Belt With Van Allen Probes Relativistic Electron-Proton Telescope Data

NASA Technical Reports Server (NTRS)

Kanekal, S. G.; Li, X.; Baker, D. N.; Selesnick, R. S.; Hoxie, V. C.

2018-01-01

An empirical model of the proton radiation belt is constructed from data taken during 2013-2017 by the Relativistic Electron-Proton Telescopes on the Van Allen Probes satellites. The model intensity is a function of time, kinetic energy in the range 18-600 megaelectronvolts, equatorial pitch angle, and L shell of proton guiding centers. Data are selected, on the basis of energy deposits in each of the nine silicon detectors, to reduce background caused by hard proton energy spectra at low L. Instrument response functions are computed by Monte Carlo integration, using simulated proton paths through a simplified structural model, to account for energy loss in shielding material for protons outside the nominal field of view. Overlap of energy channels, their wide angular response, and changing satellite orientation require the model dependencies on all three independent variables be determined simultaneously. This is done by least squares minimization with a customized steepest descent algorithm. Model uncertainty accounts for statistical data error and systematic error in the simulated instrument response. A proton energy spectrum is also computed from data taken during the 8 January 2014 solar event, to illustrate methods for the simpler case of an isotropic and homogeneous model distribution. Radiation belt and solar proton results are compared to intensities computed with a simplified, on-axis response that can provide a good approximation under limited circumstances.

Modeling the Proton Radiation Belt With Van Allen Probes Relativistic Electron-Proton Telescope Data

NASA Astrophysics Data System (ADS)

Selesnick, R. S.; Baker, D. N.; Kanekal, S. G.; Hoxie, V. C.; Li, X.

2018-01-01

An empirical model of the proton radiation belt is constructed from data taken during 2013-2017 by the Relativistic Electron-Proton Telescopes on the Van Allen Probes satellites. The model intensity is a function of time, kinetic energy in the range 18-600 MeV, equatorial pitch angle, and L shell of proton guiding centers. Data are selected, on the basis of energy deposits in each of the nine silicon detectors, to reduce background caused by hard proton energy spectra at low L. Instrument response functions are computed by Monte Carlo integration, using simulated proton paths through a simplified structural model, to account for energy loss in shielding material for protons outside the nominal field of view. Overlap of energy channels, their wide angular response, and changing satellite orientation require the model dependencies on all three independent variables be determined simultaneously. This is done by least squares minimization with a customized steepest descent algorithm. Model uncertainty accounts for statistical data error and systematic error in the simulated instrument response. A proton energy spectrum is also computed from data taken during the 8 January 2014 solar event, to illustrate methods for the simpler case of an isotropic and homogeneous model distribution. Radiation belt and solar proton results are compared to intensities computed with a simplified, on-axis response that can provide a good approximation under limited circumstances.

Apollo oxygen tank stratification analysis, volume 2

NASA Technical Reports Server (NTRS)

Barton, J. E.; Patterson, H. W.

1972-01-01

An analysis of flight performance of the Apollo 15 cryogenic oxygen tanks was conducted with the variable grid stratification math model developed earlier in the program. Flight conditions investigated were the CMP-EVA and one passive thermal control period which exhibited heater temperature characteristics not previously observed. Heater temperatures for these periods were simulated with the math model using flight acceleration data. Simulation results (heater temperature and tank pressure) compared favorably with the Apollo 15 flight data, and it was concluded that tank performance was nominal. Math model modifications were also made to improve the simulation accuracy. The modifications included the addition of the effects of the tank wall thermal mass and an improved system flow distribution model. The modifications improved the accuracy of simulated pressure response based on comparisons with flight data.

Method and system to perform energy-extraction based active noise control

NASA Technical Reports Server (NTRS)

Kelkar, Atul (Inventor); Joshi, Suresh M. (Inventor)

2009-01-01

A method to provide active noise control to reduce noise and vibration in reverberant acoustic enclosures such as aircraft, vehicles, appliances, instruments, industrial equipment and the like is presented. A continuous-time multi-input multi-output (MIMO) state space mathematical model of the plant is obtained via analytical modeling and system identification. Compensation is designed to render the mathematical model passive in the sense of mathematical system theory. The compensated system is checked to ensure robustness of the passive property of the plant. The check ensures that the passivity is preserved if the mathematical model parameters are perturbed from nominal values. A passivity-based controller is designed and verified using numerical simulations and then tested. The controller is designed so that the resulting closed-loop response shows the desired noise reduction.

Comparison of Homogeneous and Heterogeneous CFD Fuel Models for Phase I of the IAEA CRP on HTR Uncertainties Benchmark

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gerhard Strydom; Su-Jong Yoon

2014-04-01

Computational Fluid Dynamics (CFD) evaluation of homogeneous and heterogeneous fuel models was performed as part of the Phase I calculations of the International Atomic Energy Agency (IAEA) Coordinate Research Program (CRP) on High Temperature Reactor (HTR) Uncertainties in Modeling (UAM). This study was focused on the nominal localized stand-alone fuel thermal response, as defined in Ex. I-3 and I-4 of the HTR UAM. The aim of the stand-alone thermal unit-cell simulation is to isolate the effect of material and boundary input uncertainties on a very simplified problem, before propagation of these uncertainties are performed in subsequent coupled neutronics/thermal fluids phasesmore » on the benchmark. In many of the previous studies for high temperature gas cooled reactors, the volume-averaged homogeneous mixture model of a single fuel compact has been applied. In the homogeneous model, the Tristructural Isotropic (TRISO) fuel particles in the fuel compact were not modeled directly and an effective thermal conductivity was employed for the thermo-physical properties of the fuel compact. On the contrary, in the heterogeneous model, the uranium carbide (UCO), inner and outer pyrolytic carbon (IPyC/OPyC) and silicon carbide (SiC) layers of the TRISO fuel particles are explicitly modeled. The fuel compact is modeled as a heterogeneous mixture of TRISO fuel kernels embedded in H-451 matrix graphite. In this study, a steady-state and transient CFD simulations were performed with both homogeneous and heterogeneous models to compare the thermal characteristics. The nominal values of the input parameters are used for this CFD analysis. In a future study, the effects of input uncertainties in the material properties and boundary parameters will be investigated and reported.« less

Nonlinear electrostrictive lattice response of EuTiO3

NASA Astrophysics Data System (ADS)

Pappas, P.; Calamiotou, M.; Köhler, J.; Bussmann-Holder, A.; Liarokapis, E.

2017-07-01

An epitaxial EuTiO3 (ETO) film grown on the SrTiO3 substrate was studied at room temperature with synchrotron XRD and in situ application of an electric field (nominally up to 7.8 kV/cm) in near grazing incidence geometry, in order to monitor the response of the lattice to the field. 2D diffraction images show that apparently misoriented coherently diffracting domains are present close to the surface whereas the film diffracts more as a single crystal towards the interface. Diffraction intensity profiles recorded from the near surface region of the EuTiO3 film showed systematic modifications upon the application of the electric field, indicating that at a critical electric field (nominally above 3.1 kV/cm), there is a clear change in the lattice response to the field, which was much stronger when the field was almost parallel to the diffraction vector. The data suggest that the ETO film, nominally paraelectric at room temperature, transforms under the application of a critical electric field to piezoelectric in agreement with a theoretical analysis based on a double-well potential. In order to exclude effects arising from the substrate, this has been investigated separately and shown not to be affected by the field.

Arousal, working memory capacity, and sexual decision-making in men.

PubMed

Spokes, Tara; Hine, Donald W; Marks, Anthony D G; Quain, Peter; Lykins, Amy D

2014-08-01

This study investigated whether working memory capacity (WMC) moderated the relationship between physiological arousal and sexual decision making. A total of 59 men viewed 20 consensual and 20 non-consensual images of heterosexual interaction while their physiological arousal levels were recorded using skin conductance response. Participants also completed an assessment of WMC and a date-rape analogue task for which they had to identify the point at which an average Australian male would cease all sexual advances in response to verbal and/or physical resistance from a female partner. Participants who were more physiologically aroused by and spent more time viewing the non-consensual sexual imagery nominated significantly later stopping points on the date-rape analogue task. Consistent with our predictions, the relationship between physiological arousal and nominated stopping point was strongest for participants with lower levels of WMC. For participants with high WMC, physiological arousal was unrelated to nominated stopping point. Thus, executive functioning ability (and WMC in particular) appears to play an important role in moderating men's decision making with regard to sexually aggressive behavior.

TU-A-12A-12: Improved Airway Measurement Accuracy for Low Dose Quantitative CT (qCT) Using Statistical (ASIR), at Reduced DFOV, and High Resolution Kernels in a Phantom and Swine Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yadava, G; Imai, Y; Hsieh, J

2014-06-15

Purpose: Quantitative accuracy of Iodine Hounsfield Unit (HU) in conventional single-kVp scanning is susceptible to beam-hardening effect. Dual-energy CT has unique capabilities of quantification using monochromatic CT images, but this scanning mode requires the availability of the state-of-the-art CT scanner and, therefore, is limited in routine clinical practice. Purpose of this work was to develop a beam-hardening-correction (BHC) for single-kVp CT that can linearize Iodine projections at any nominal energy, apply this approach to study Iodine response with respect to keV, and compare with dual-energy based monochromatic images obtained from material-decomposition using 80kVp and 140kVp. Methods: Tissue characterization phantoms (Gammexmore » Inc.), containing solid-Iodine inserts of different concentrations, were scanned using GE multi-slice CT scanner at 80, 100, 120, and 140 kVp. A model-based BHC algorithm was developed where Iodine was estimated using re-projection of image volume and corrected through an iterative process. In the correction, the re-projected Iodine was linearized using a polynomial mapping between monochromatic path-lengths at various nominal energies (40 to 140 keV) and physically modeled polychromatic path-lengths. The beam-hardening-corrected 80kVp and 140kVp images (linearized approximately at effective energy of the beam) were used for dual-energy material-decomposition in Water-Iodine basis-pair followed by generation of monochromatic images. Characterization of Iodine HU and noise in the images obtained from singlekVp with BHC at various nominal keV, and corresponding dual-energy monochromatic images, was carried out. Results: Iodine HU vs. keV response from single-kVp with BHC and dual-energy monochromatic images were found to be very similar, indicating that single-kVp data may be used to create material specific monochromatic equivalent using modelbased projection linearization. Conclusion: This approach may enable quantification of Iodine contrast enhancement and potential reduction in injected contrast without using dual-energy scanning. However, in general, dual-energy scanning has unique value in material characterization and quantification, and its value cannot be discounted. GE Healthcare Employee.« less

Phase coded, micro-power impulse radar motion sensor

DOEpatents

McEwan, Thomas E.

1996-01-01

A motion sensing, micro-power impulse radar MIR impresses on the transmitted signal, or the received pulse timing signal, one or more frequencies lower than the pulse repetition frequency, that become intermediate frequencies in a "IF homodyne" receiver. Thus, many advantages of classical RF receivers can be thereby be realized with ultra-wide band radar. The sensor includes a transmitter which transmits a sequence of electromagnetic pulses in response to a transmit timing signal at a nominal pulse repetition frequency. A receiver samples echoes of the sequence of electromagnetic pulses from objects within the field with controlled timing, in response to a receive timing signal, and generates a sample signal in response to the samples. A timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The relative timing of the transmit timing signal and the receive timing signal is modulated between a first relative delay and a second relative delay at an intermediate frequency, causing the receiver to sample the echoes such that the time between transmissions of pulses in the sequence and samples by the receiver is modulated at the intermediate frequency. Modulation may be executed by modulating the pulse repetition frequency which drives the transmitter, by modulating the delay circuitry which controls the relative timing of the sample strobe, or by modulating amplitude of the transmitted pulses. The electromagnetic pulses will have a nominal center frequency related to pulse width, and the first relative delay and the second relative delay between which the timing signals are modulated, differ by less than the nominal pulse width, and preferably by about one-quarter wavelength at the nominal center frequency of the transmitted pulses.

Phase coded, micro-power impulse radar motion sensor

DOEpatents

McEwan, T.E.

1996-05-21

A motion sensing, micro-power impulse radar MIR impresses on the transmitted signal, or the received pulse timing signal, one or more frequencies lower than the pulse repetition frequency, that become intermediate frequencies in a ``IF homodyne`` receiver. Thus, many advantages of classical RF receivers can be thereby be realized with ultra-wide band radar. The sensor includes a transmitter which transmits a sequence of electromagnetic pulses in response to a transmit timing signal at a nominal pulse repetition frequency. A receiver samples echoes of the sequence of electromagnetic pulses from objects within the field with controlled timing, in response to a receive timing signal, and generates a sample signal in response to the samples. A timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The relative timing of the transmit timing signal and the receive timing signal is modulated between a first relative delay and a second relative delay at an intermediate frequency, causing the receiver to sample the echoes such that the time between transmissions of pulses in the sequence and samples by the receiver is modulated at the intermediate frequency. Modulation may be executed by modulating the pulse repetition frequency which drives the transmitter, by modulating the delay circuitry which controls the relative timing of the sample strobe, or by modulating amplitude of the transmitted pulses. The electromagnetic pulses will have a nominal center frequency related to pulse width, and the first relative delay and the second relative delay between which the timing signals are modulated, differ by less than the nominal pulse width, and preferably by about one-quarter wavelength at the nominal center frequency of the transmitted pulses. 5 figs.

System and Method for Outlier Detection via Estimating Clusters

NASA Technical Reports Server (NTRS)

Iverson, David J. (Inventor)

2016-01-01

An efficient method and system for real-time or offline analysis of multivariate sensor data for use in anomaly detection, fault detection, and system health monitoring is provided. Models automatically derived from training data, typically nominal system data acquired from sensors in normally operating conditions or from detailed simulations, are used to identify unusual, out of family data samples (outliers) that indicate possible system failure or degradation. Outliers are determined through analyzing a degree of deviation of current system behavior from the models formed from the nominal system data. The deviation of current system behavior is presented as an easy to interpret numerical score along with a measure of the relative contribution of each system parameter to any off-nominal deviation. The techniques described herein may also be used to "clean" the training data.

Simulation Modeling for Off-Nominal Conditions - Where Are We Today?

NASA Technical Reports Server (NTRS)

Shah, Gautam H.; Foster, John V.; Cunningham, Kevin

2010-01-01

The modeling of aircraft flight characteris4cs in off-nominal or otherwise adverse conditions has become increasingly important for simulation in the loss-of-control arena. Adverse conditions include environmentally-induced upsets such as wind shear or wake vortex encounters; off-nominal flight conditions, such as stall or departure; on-board systems failures; and structural failures or aircraft damage. Spirited discussions in the research community are taking place as to the fidelity and data requirements for adequate representation of vehicle dynamics under such conditions for a host of research areas, including recovery training, flight controls development, trajectory guidance/planning, and envelope limiting. The increasing need for multiple sources of data (empirical, computational, experimental) for modeling across a larger flight envelope leads to challenges in developing methods of appropriately applying or combining such data, particularly in a dynamic flight environment with a physically and/or aerodynamically asymmetric vehicle. Traditional simplifications and symmetry assumptions in current modeling methodology may no longer be valid. Furthermore, once modeled, challenges abound in the validation of flight dynamics characteristics in adverse flight regimes

Modeling Off-Nominal Behavior in SysML

NASA Technical Reports Server (NTRS)

Day, John; Donahue, Kenny; Ingham, Mitch; Kadesch, Alex; Kennedy, Kit; Post, Ethan

2012-01-01

Fault Management is an essential part of the system engineering process that is limited in its effectiveness by the ad hoc nature of the applied approaches and methods. Providing a rigorous way to develop and describe off-nominal behavior is a necessary step in the improvement of fault management, and as a result, will enable safe, reliable and available systems even as system complexity increases... The basic concepts described in this paper provide a foundation to build a larger set of necessary concepts and relationships for precise modeling of off-nominal behavior, and a basis for incorporating these ideas into the overall systems engineering process.. The simple FMEA example provided applies the modeling patterns we have developed and illustrates how the information in the model can be used to reason about the system and derive typical fault management artifacts.. A key insight from the FMEA work was the utility of defining failure modes as the "inverse of intent", and deriving this from the behavior models.. Additional work is planned to extend these ideas and capabilities to other types of relevant information and additional products.

Combined feedforward and model-assisted active disturbance rejection control for non-minimum phase system.

PubMed

Sun, Li; Li, Donghai; Gao, Zhiqiang; Yang, Zhao; Zhao, Shen

2016-09-01

Control of the non-minimum phase (NMP) system is challenging, especially in the presence of modelling uncertainties and external disturbances. To this end, this paper presents a combined feedforward and model-assisted Active Disturbance Rejection Control (MADRC) strategy. Based on the nominal model, the feedforward controller is used to produce a tracking performance that has minimum settling time subject to a prescribed undershoot constraint. On the other hand, the unknown disturbances and uncertain dynamics beyond the nominal model are compensated by MADRC. Since the conventional Extended State Observer (ESO) is not suitable for the NMP system, a model-assisted ESO (MESO) is proposed based on the nominal observable canonical form. The convergence of MESO is proved in time domain. The stability, steady-state characteristics and robustness of the closed-loop system are analyzed in frequency domain. The proposed strategy has only one tuning parameter, i.e., the bandwidth of MESO, which can be readily determined with a prescribed robustness level. Some comparative examples are given to show the efficacy of the proposed method. This paper depicts a promising prospect of the model-assisted ADRC in dealing with complex systems. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Current Pressure Transducer Application of Model-based Prognostics Using Steady State Conditions

NASA Technical Reports Server (NTRS)

Teubert, Christopher; Daigle, Matthew J.

2014-01-01

Prognostics is the process of predicting a system's future states, health degradation/wear, and remaining useful life (RUL). This information plays an important role in preventing failure, reducing downtime, scheduling maintenance, and improving system utility. Prognostics relies heavily on wear estimation. In some components, the sensors used to estimate wear may not be fast enough to capture brief transient states that are indicative of wear. For this reason it is beneficial to be capable of detecting and estimating the extent of component wear using steady-state measurements. This paper details a method for estimating component wear using steady-state measurements, describes how this is used to predict future states, and presents a case study of a current/pressure (I/P) Transducer. I/P Transducer nominal and off-nominal behaviors are characterized using a physics-based model, and validated against expected and observed component behavior. This model is used to map observed steady-state responses to corresponding fault parameter values in the form of a lookup table. This method was chosen because of its fast, efficient nature, and its ability to be applied to both linear and non-linear systems. Using measurements of the steady state output, and the lookup table, wear is estimated. A regression is used to estimate the wear propagation parameter and characterize the damage progression function, which are used to predict future states and the remaining useful life of the system.

Optimizing multi-dimensional high throughput screening using zebrafish.

PubMed

Truong, Lisa; Bugel, Sean M; Chlebowski, Anna; Usenko, Crystal Y; Simonich, Michael T; Simonich, Staci L Massey; Tanguay, Robert L

2016-10-01

The use of zebrafish for high throughput screening (HTS) for chemical bioactivity assessments is becoming routine in the fields of drug discovery and toxicology. Here we report current recommendations from our experiences in zebrafish HTS. We compared the effects of different high throughput chemical delivery methods on nominal water concentration, chemical sorption to multi-well polystyrene plates, transcription responses, and resulting whole animal responses. We demonstrate that digital dispensing consistently yields higher data quality and reproducibility compared to standard plastic tip-based liquid handling. Additionally, we illustrate the challenges in using this sensitive model for chemical assessment when test chemicals have trace impurities. Adaptation of these better practices for zebrafish HTS should increase reproducibility across laboratories. Copyright © 2016 Elsevier Inc. All rights reserved.

Nominalization and Alternations in Biomedical Language

PubMed Central

Cohen, K. Bretonnel; Palmer, Martha; Hunter, Lawrence

2008-01-01

Background This paper presents data on alternations in the argument structure of common domain-specific verbs and their associated verbal nominalizations in the PennBioIE corpus. Alternation is the term in theoretical linguistics for variations in the surface syntactic form of verbs, e.g. the different forms of stimulate in FSH stimulates follicular development and follicular development is stimulated by FSH. The data is used to assess the implications of alternations for biomedical text mining systems and to test the fit of the sublanguage model to biomedical texts. Methodology/Principal Findings We examined 1,872 tokens of the ten most common domain-specific verbs or their zero-related nouns in the PennBioIE corpus and labelled them for the presence or absence of three alternations. We then annotated the arguments of 746 tokens of the nominalizations related to these verbs and counted alternations related to the presence or absence of arguments and to the syntactic position of non-absent arguments. We found that alternations are quite common both for verbs and for nominalizations. We also found a previously undescribed alternation involving an adjectival present participle. Conclusions/Significance We found that even in this semantically restricted domain, alternations are quite common, and alternations involving nominalizations are exceptionally diverse. Nonetheless, the sublanguage model applies to biomedical language. We also report on a previously undescribed alternation involving an adjectival present participle. PMID:18779866

Investigating the Impact of Off-Nominal Events on High-Density "Green" Arrivals

NASA Technical Reports Server (NTRS)

Callatine, Todd J.; Cabrall, Christopher; Kupfer, Michael; Martin, Lynne; Mercer, Joey; Palmer, Everett A.

2012-01-01

Trajectory-based controller tools developed to support a schedule-based terminal-area air traffic management (ATM) concept have been shown effective for enabling green arrivals along Area Navigation (RNAV) routes in moderately high-density traffic conditions. A recent human-in-the-loop simulation investigated the robustness of the concept and tools to off-nominal events events that lead to situations in which runway arrival schedules require adjustments and controllers can no longer use speed control alone to impose the necessary delays. Study participants included a terminal-area Traffic Management Supervisor responsible for adjusting the schedules. Sector-controller participants could issue alternate RNAV transition routes to absorb large delays. The study also included real-time winds/wind-forecast changes. The results indicate that arrival spacing accuracy, schedule conformance, and tool usage and usefulness are similar to that observed in simulations of nominal operations. However, the time and effort required to recover from an off-nominal event is highly context-sensitive, and impacted by the required schedule adjustments and control methods available for managing the evolving situation. The research suggests ways to bolster the off-nominal recovery process, and highlights challenges related to using human-in-the-loop simulation to investigate the safety and robustness of advanced ATM concepts.

An adaptive drug delivery design using neural networks for effective treatment of infectious diseases: a simulation study.

PubMed

Padhi, Radhakant; Bhardhwaj, Jayender R

2009-06-01

An adaptive drug delivery design is presented in this paper using neural networks for effective treatment of infectious diseases. The generic mathematical model used describes the coupled evolution of concentration of pathogens, plasma cells, antibodies and a numerical value that indicates the relative characteristic of a damaged organ due to the disease under the influence of external drugs. From a system theoretic point of view, the external drugs can be interpreted as control inputs, which can be designed based on control theoretic concepts. In this study, assuming a set of nominal parameters in the mathematical model, first a nonlinear controller (drug administration) is designed based on the principle of dynamic inversion. This nominal drug administration plan was found to be effective in curing "nominal model patients" (patients whose immunological dynamics conform to the mathematical model used for the control design exactly. However, it was found to be ineffective in curing "realistic model patients" (patients whose immunological dynamics may have off-nominal parameter values and possibly unwanted inputs) in general. Hence, to make the drug delivery dosage design more effective for realistic model patients, a model-following adaptive control design is carried out next by taking the help of neural networks, that are trained online. Simulation studies indicate that the adaptive controller proposed in this paper holds promise in killing the invading pathogens and healing the damaged organ even in the presence of parameter uncertainties and continued pathogen attack. Note that the computational requirements for computing the control are very minimal and all associated computations (including the training of neural networks) can be carried out online. However it assumes that the required diagnosis process can be carried out at a sufficient faster rate so that all the states are available for control computation.

Empathy and nonattachment independently predict peer nominations of prosocial behavior of adolescents

PubMed Central

Sahdra, Baljinder K.; Ciarrochi, Joseph; Parker, Philip D.; Marshall, Sarah; Heaven, Patrick

2015-01-01

There is a plethora of research showing that empathy promotes prosocial behavior among young people. We examined a relatively new construct in the mindfulness literature, nonattachment, defined as a flexible way of relating to one's experiences without clinging to or suppressing them. We tested whether nonattachment could predict prosociality above and beyond empathy. Nonattachment implies high cognitive flexibility and sufficient mental resources to step out of excessive self-cherishing to be there for others in need. Multilevel Poisson models using a sample of 15-year olds (N = 1831) showed that empathy and nonattachment independently predicted prosocial behaviors of helpfulness and kindness, as judged by same-sex and opposite-sex peers, except for when boys nominated girls. The effects of nonattachment remained substantial in more conservative models including self-esteem and peer nominations of liking. PMID:25852590

The Youth-Nominated Support Team-Version II for Suicidal Adolescents: A Randomized Controlled Intervention Trial

ERIC Educational Resources Information Center

King, Cheryl A.; Klaus, Nicole; Kramer, Anne; Venkataraman, Sanjeev; Quinlan, Paul; Gillespie, Brenda

2009-01-01

The purpose of this study was to examine the efficacy of the Youth-Nominated Support Team-Version II (YST-II) for suicidal adolescents, an intervention based on social support and health behavior models, which was designed to supplement standard treatments. Psychiatrically hospitalized and suicidal adolescents, 13-17 years of age, were randomly…

Modeling the relationship between body weight and energy intake: A molecular diffusion-based approach

PubMed Central

2012-01-01

Background Body weight is at least partly controlled by the choices made by a human in response to external stimuli. Changes in body weight are mainly caused by energy intake. By analyzing the mechanisms involved in food intake, we considered that molecular diffusion plays an important role in body weight changes. We propose a model based on Fick's second law of diffusion to simulate the relationship between energy intake and body weight. Results This model was applied to food intake and body weight data recorded in humans; the model showed a good fit to the experimental data. This model was also effective in predicting future body weight. Conclusions In conclusion, this model based on molecular diffusion provides a new insight into the body weight mechanisms. Reviewers This article was reviewed by Dr. Cabral Balreira (nominated by Dr. Peter Olofsson), Prof. Yang Kuang and Dr. Chao Chen. PMID:22742862

INDUCTIVE SYSTEM HEALTH MONITORING WITH STATISTICAL METRICS

NASA Technical Reports Server (NTRS)

Iverson, David L.

2005-01-01

Model-based reasoning is a powerful method for performing system monitoring and diagnosis. Building models for model-based reasoning is often a difficult and time consuming process. The Inductive Monitoring System (IMS) software was developed to provide a technique to automatically produce health monitoring knowledge bases for systems that are either difficult to model (simulate) with a computer or which require computer models that are too complex to use for real time monitoring. IMS processes nominal data sets collected either directly from the system or from simulations to build a knowledge base that can be used to detect anomalous behavior in the system. Machine learning and data mining techniques are used to characterize typical system behavior by extracting general classes of nominal data from archived data sets. In particular, a clustering algorithm forms groups of nominal values for sets of related parameters. This establishes constraints on those parameter values that should hold during nominal operation. During monitoring, IMS provides a statistically weighted measure of the deviation of current system behavior from the established normal baseline. If the deviation increases beyond the expected level, an anomaly is suspected, prompting further investigation by an operator or automated system. IMS has shown potential to be an effective, low cost technique to produce system monitoring capability for a variety of applications. We describe the training and system health monitoring techniques of IMS. We also present the application of IMS to a data set from the Space Shuttle Columbia STS-107 flight. IMS was able to detect an anomaly in the launch telemetry shortly after a foam impact damaged Columbia's thermal protection system.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yingchen; Tan, Jin; Krad, Ibrahim

Power system frequency needs to be maintained close to its nominal value at all times to successfully balance load and generation and maintain system reliability. Adequate primary frequency response and secondary frequency response are the primary forces to correct an energy imbalance at the second-to-minute level. As wind energy becomes a larger portion of the world's energy portfolio, there is an increased need for wind to provide frequency response. This paper addresses one of the major concerns about using wind for frequency regulation: the unknown factor of the interaction between primary and secondary reserves. The lack of a commercially availablemore » tool to model this has limited the energy industry's understanding of when the depletion of primary reserves will impact the performance of secondary response or vice versa. This paper investigates the issue by developing a multi-area frequency response integration tool with combined primary and secondary capabilities. The simulation is conducted in close coordination with economical energy scheduling scenarios to ensure credible simulation results.« less

Dielectric properties of vertically aligned multi-walled carbon nanotubes in the terahertz and mid-infrared range

NASA Astrophysics Data System (ADS)

Thomson, Mark D.; Zouaghi, Wissem; Meng, Fanqi; Wiecha, Matthias M.; Rabia, Kaneez; Heinlein, Thorsten; Hussein, Laith; Babu, Deepu; Yadav, Sandeep; Engstler, Jörg; Schneider, Jörg J.; Nicoloso, Norbert; Rychetský, Ivan; Kužel, Petr; Roskos, Hartmut G.

2018-01-01

We investigate the broadband dielectric properties of vertically aligned, multi-wall carbon nanotubes (VACNT), over both the terahertz (THz) and mid-infrared spectral ranges. The nominally undoped, metallic VACNT samples are probed at normal incidence, i.e. the response is predominantly due to polarisation perpendicular to the CNT axis. A detailed comparison of various conductivity models and previously reported results is presented for the non-Drude behaviour we observe in the conventional THz range (up to 2.5 THz). Extension to the mid-infrared range reveals an absorption peak at \

Generalized Full-Information Item Bifactor Analysis

PubMed Central

Cai, Li; Yang, Ji Seung; Hansen, Mark

2011-01-01

Full-information item bifactor analysis is an important statistical method in psychological and educational measurement. Current methods are limited to single group analysis and inflexible in the types of item response models supported. We propose a flexible multiple-group item bifactor analysis framework that supports a variety of multidimensional item response theory models for an arbitrary mixing of dichotomous, ordinal, and nominal items. The extended item bifactor model also enables the estimation of latent variable means and variances when data from more than one group are present. Generalized user-defined parameter restrictions are permitted within or across groups. We derive an efficient full-information maximum marginal likelihood estimator. Our estimation method achieves substantial computational savings by extending Gibbons and Hedeker’s (1992) bifactor dimension reduction method so that the optimization of the marginal log-likelihood only requires two-dimensional integration regardless of the dimensionality of the latent variables. We use simulation studies to demonstrate the flexibility and accuracy of the proposed methods. We apply the model to study cross-country differences, including differential item functioning, using data from a large international education survey on mathematics literacy. PMID:21534682

Small Aircraft Transportation System, Higher Volume Operations Concept: Off-Nominal Operations

NASA Technical Reports Server (NTRS)

Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Conway, Sheila R.

2005-01-01

This document expands the Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept to include off-nominal conditions. The general philosophy underlying the HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). During periods of poor weather, a block of airspace would be established around designated non-towered, non-radar airports. Aircraft flying enroute to a SATS airport would be on a standard instrument flight rules flight clearance with Air Traffic Control providing separation services. Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Previous work developed the procedures for normal HVO operations. This document provides details for off-nominal and emergency procedures for situations that could be expected to occur in a future SCA.

Model Development and Experimental Validation of the Fusible Heat Sink Design for Exploration Vehicles

NASA Technical Reports Server (NTRS)

Cognata, Thomas J.; Leimkuehler, Thomas O.; Sheth, Rubik B.; Le,Hung

2012-01-01

The Fusible Heat Sink is a novel vehicle heat rejection technology which combines a flow through radiator with a phase change material. The combined technologies create a multi-function device able to shield crew members against Solar Particle Events (SPE), reduce radiator extent by permitting sizing to the average vehicle heat load rather than to the peak vehicle heat load, and to substantially absorb heat load excursions from the average while constantly maintaining thermal control system setpoints. This multi-function technology provides great flexibility for mission planning, making it possible to operate a vehicle in hot or cold environments and under high or low heat load conditions for extended periods of time. This paper describes the model development and experimental validation of the Fusible Heat Sink technology. The model developed was intended to meet the radiation and heat rejection requirements of a nominal MMSEV mission. Development parameters and results, including sizing and model performance will be discussed. From this flight-sized model, a scaled test-article design was modeled, designed, and fabricated for experimental validation of the technology at Johnson Space Center thermal vacuum chamber facilities. Testing showed performance comparable to the model at nominal loads and the capability to maintain heat loads substantially greater than nominal for extended periods of time.

Model Development and Experimental Validation of the Fusible Heat Sink Design for Exploration Vehicles

NASA Technical Reports Server (NTRS)

Cognata, Thomas J.; Leimkuehler, Thomas; Sheth, Rubik; Le, Hung

2013-01-01

The Fusible Heat Sink is a novel vehicle heat rejection technology which combines a flow through radiator with a phase change material. The combined technologies create a multi-function device able to shield crew members against Solar Particle Events (SPE), reduce radiator extent by permitting sizing to the average vehicle heat load rather than to the peak vehicle heat load, and to substantially absorb heat load excursions from the average while constantly maintaining thermal control system setpoints. This multi-function technology provides great flexibility for mission planning, making it possible to operate a vehicle in hot or cold environments and under high or low heat load conditions for extended periods of time. This paper describes the modeling and experimental validation of the Fusible Heat Sink technology. The model developed was intended to meet the radiation and heat rejection requirements of a nominal MMSEV mission. Development parameters and results, including sizing and model performance will be discussed. From this flight-sized model, a scaled test-article design was modeled, designed, and fabricated for experimental validation of the technology at Johnson Space Center thermal vacuum chamber facilities. Testing showed performance comparable to the model at nominal loads and the capability to maintain heat loads substantially greater than nominal for extended periods of time.

Automated Generation of Fault Management Artifacts from a Simple System Model

NASA Technical Reports Server (NTRS)

Kennedy, Andrew K.; Day, John C.

2013-01-01

Our understanding of off-nominal behavior - failure modes and fault propagation - in complex systems is often based purely on engineering intuition; specific cases are assessed in an ad hoc fashion as a (fallible) fault management engineer sees fit. This work is an attempt to provide a more rigorous approach to this understanding and assessment by automating the creation of a fault management artifact, the Failure Modes and Effects Analysis (FMEA) through querying a representation of the system in a SysML model. This work builds off the previous development of an off-nominal behavior model for the upcoming Soil Moisture Active-Passive (SMAP) mission at the Jet Propulsion Laboratory. We further developed the previous system model to more fully incorporate the ideas of State Analysis, and it was restructured in an organizational hierarchy that models the system as layers of control systems while also incorporating the concept of "design authority". We present software that was developed to traverse the elements and relationships in this model to automatically construct an FMEA spreadsheet. We further discuss extending this model to automatically generate other typical fault management artifacts, such as Fault Trees, to efficiently portray system behavior, and depend less on the intuition of fault management engineers to ensure complete examination of off-nominal behavior.

Miller, Mulberry, Brewer, and Evered nominations. Hearing before Committee on Energy and Natural Resources, United States Senate, Ninety-Seventh Congress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-01-01

Four presidential nominees were questioned by members of the committee and by 11 witnesses, who also made statements pertinent to the nomination: Daniel N. Miller, Jr., to be Ass't. Secy. of Interior for Energy and Minerals; Richard Mulberry, to be Inspector General, Dept. of Interior; Shelby T. Brewer to be Ass't. Secy. for Nuclear Energy; and J. Erich Evered, to be Administrator of the Energy Information Administration, Department of Energy. The statements and responses are followed by additional material submitted for the record and informational statements and responses of the nominees. The nominees were questioned about past activities and theirmore » policy goals as well as their plans for conducting their respective offices. (DCK)« less

Spacecraft Thermal and Optical Modeling Impacts on Estimation of the GRAIL Lunar Gravity Field

NASA Technical Reports Server (NTRS)

Fahnestock, Eugene G.; Park, Ryan S.; Yuan, Dah-Ning; Konopliv, Alex S.

2012-01-01

We summarize work performed involving thermo-optical modeling of the two Gravity Recovery And Interior Laboratory (GRAIL) spacecraft. We derived several reconciled spacecraft thermo-optical models having varying detail. We used the simplest in calculating SRP acceleration, and used the most detailed to calculate acceleration due to thermal re-radiation. For the latter, we used both the output of pre-launch finite-element-based thermal simulations and downlinked temperature sensor telemetry. The estimation process to recover the lunar gravity field utilizes both a nominal thermal re-radiation accleration history and an apriori error model derived from that plus an off-nominal history, which bounds parameter uncertainties as informed by sensitivity studies.

Creep of a Silicon Nitride Under Various Specimen/Loading Configurations

NASA Technical Reports Server (NTRS)

Choi, Sung R.; Powers, Lynn M.; Holland, Frederic A.; Gyekenyesi, John P.; Holland, F. A. (Technical Monitor)

2000-01-01

Extensive creep testing of a hot-pressed silicon nitride (NC132) was performed at 1300 C in air using five different specimen/loading configurations, including pure tension, pure compression, four-point uniaxial flexure, ball-on-ring biaxial flexure, and ring-on-ring biaxial flexure. Nominal creep strain and its rate for a given nominal applied stress were greatest in tension, least in compression, and intermediate in uniaxial and biaxial flexure. Except for the case of compressive loading, nominal creep strain generally decreased with time, resulting in less-defined steady-state condition. Of the four different creep formulations - power-law, hyperbolic sine, step, redistribution models - the conventional power-law model still provides the most convenient and reasonable means to estimate simple, quantitative creep parameters of the material. Predictions of creep deformation for the case of multiaxial stress state (biaxial flexure) were made based on pure tension and compression creep data by using the design code CARES/Creep.

A method for nonlinear exponential regression analysis

NASA Technical Reports Server (NTRS)

Junkin, B. G.

1971-01-01

A computer-oriented technique is presented for performing a nonlinear exponential regression analysis on decay-type experimental data. The technique involves the least squares procedure wherein the nonlinear problem is linearized by expansion in a Taylor series. A linear curve fitting procedure for determining the initial nominal estimates for the unknown exponential model parameters is included as an integral part of the technique. A correction matrix was derived and then applied to the nominal estimate to produce an improved set of model parameters. The solution cycle is repeated until some predetermined criterion is satisfied.

A Fully Coupled Multi-Rigid-Body Fuel Slosh Dynamics Model Applied to the Triana Stack

NASA Technical Reports Server (NTRS)

London, K. W.

2001-01-01

A somewhat general multibody model is presented that accounts for energy dissipation associated with fuel slosh and which unifies some of the existing more specialized representations. This model is used to predict the mutation growth time constant for the Triana Spacecraft, or Stack, consisting of the Triana Observatory mated with the Gyroscopic Upper Stage of GUS (includes the solid rocket motor, SRM, booster). At the nominal spin rate of 60 rpm and with 145 kg of hydrazine propellant on board, a time constant of 116 s is predicted for worst case sloshing of a spherical slug model compared to 1,681 s (nominal), 1,043 s (worst case) for sloshing of a three degree of freedom pendulum model.

Using explanatory crop models to develop simple tools for Advanced Life Support system studies

NASA Technical Reports Server (NTRS)

Cavazzoni, J.

2004-01-01

System-level analyses for Advanced Life Support require mathematical models for various processes, such as for biomass production and waste management, which would ideally be integrated into overall system models. Explanatory models (also referred to as mechanistic or process models) would provide the basis for a more robust system model, as these would be based on an understanding of specific processes. However, implementing such models at the system level may not always be practicable because of their complexity. For the area of biomass production, explanatory models were used to generate parameters and multivariable polynomial equations for basic models that are suitable for estimating the direction and magnitude of daily changes in canopy gas-exchange, harvest index, and production scheduling for both nominal and off-nominal growing conditions. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

Allogeneic substitution for nominal antigen-specific T-cell clone reactivity in schistosomiasis.

PubMed Central

Linette, G P; Lammie, P J; Phillips, S M

1986-01-01

The present studies have established the nature of a T-cell clone which demonstrates dual reactivity directed against Schistosoma mansoni antigen presented by syngeneic antigen presenting cells and against allogeneic cells. Clone G4, when stimulated by either antigen (SEA) or allogeneic cells (PL/J), exhibits similar functional and phenotypic characteristics. A subclone of G4, G4A.1, which has been maintained in continuous mixed lymphocyte culture for 12 months (in the absence of SEA), retains comparable reactivity with respect to proliferation and ability to produce lymphokines, transfer delayed-type hypersensitivity, and produce in vitro granulomas in response to SEA. Normal antigenic stimulation is highly contingent upon I-Ab compatibility while antibody blocking experiments map allo-reactivity to I-Eu. The failure of B10.PL spleen cells to stimulate G4, however, suggests that alloreactivity may be directed against the recently described Mls X locus. Both allogeneic and nominal antigen induced T-cell activation are blocked by antibody directed against L3T4A, confirming Class II MHC restriction for both types of stimulation. These studies suggest that stimulation of T cells by either alloantigen or nominal antigen elicits qualitatively similar functional profiles, and further suggest the feasibility of producing large numbers of nominal antigen reactive cloned T cells in the absence of nominal antigen under mixed lymphocyte culture conditions. PMID:2420707

Robust model predictive control for constrained continuous-time nonlinear systems

NASA Astrophysics Data System (ADS)

Sun, Tairen; Pan, Yongping; Zhang, Jun; Yu, Haoyong

2018-02-01

In this paper, a robust model predictive control (MPC) is designed for a class of constrained continuous-time nonlinear systems with bounded additive disturbances. The robust MPC consists of a nonlinear feedback control and a continuous-time model-based dual-mode MPC. The nonlinear feedback control guarantees the actual trajectory being contained in a tube centred at the nominal trajectory. The dual-mode MPC is designed to ensure asymptotic convergence of the nominal trajectory to zero. This paper extends current results on discrete-time model-based tube MPC and linear system model-based tube MPC to continuous-time nonlinear model-based tube MPC. The feasibility and robustness of the proposed robust MPC have been demonstrated by theoretical analysis and applications to a cart-damper springer system and a one-link robot manipulator.

Ring rolling process simulation for geometry optimization

NASA Astrophysics Data System (ADS)

Franchi, Rodolfo; Del Prete, Antonio; Donatiello, Iolanda; Calabrese, Maurizio

2017-10-01

Ring Rolling is a complex hot forming process where different rolls are involved in the production of seamless rings. Since each roll must be independently controlled, different speed laws must be set; usually, in the industrial environment, a milling curve is introduced to monitor the shape of the workpiece during the deformation in order to ensure the correct ring production. In the present paper a ring rolling process has been studied and optimized in order to obtain anular components to be used in aerospace applications. In particular, the influence of process input parameters (feed rate of the mandrel and angular speed of main roll) on geometrical features of the final ring has been evaluated. For this purpose, a three-dimensional finite element model for HRR (Hot Ring Rolling) has been implemented in SFTC DEFORM V11. The FEM model has been used to formulate a proper optimization problem. The optimization procedure has been implemented in the commercial software DS ISight in order to find the combination of process parameters which allows to minimize the percentage error of each obtained dimension with respect to its nominal value. The software allows to find the relationship between input and output parameters applying Response Surface Methodology (RSM), by using the exact values of output parameters in the control points of the design space explored through FEM simulation. Once this relationship is known, the values of the output parameters can be calculated for each combination of the input parameters. After the calculation of the response surfaces for the selected output parameters, an optimization procedure based on Genetic Algorithms has been applied. At the end, the error between each obtained dimension and its nominal value has been minimized. The constraints imposed were the maximum values of standard deviations of the dimensions obtained for the final ring.

Analysis of the Influence of microRNAs in Lithium Response in Bipolar Disorder.

PubMed

Reinbold, Céline S; Forstner, Andreas J; Hecker, Julian; Fullerton, Janice M; Hoffmann, Per; Hou, Liping; Heilbronner, Urs; Degenhardt, Franziska; Adli, Mazda; Akiyama, Kazufumi; Akula, Nirmala; Ardau, Raffaella; Arias, Bárbara; Backlund, Lena; Benabarre, Antonio; Bengesser, Susanne; Bhattacharjee, Abesh K; Biernacka, Joanna M; Birner, Armin; Marie-Claire, Cynthia; Cervantes, Pablo; Chen, Guo-Bo; Chen, Hsi-Chung; Chillotti, Caterina; Clark, Scott R; Colom, Francesc; Cousins, David A; Cruceanu, Cristiana; Czerski, Piotr M; Dayer, Alexandre; Étain, Bruno; Falkai, Peter; Frisén, Louise; Gard, Sébastien; Garnham, Julie S; Goes, Fernando S; Grof, Paul; Gruber, Oliver; Hashimoto, Ryota; Hauser, Joanna; Herms, Stefan; Jamain, Stéphane; Jiménez, Esther; Kahn, Jean-Pierre; Kassem, Layla; Kittel-Schneider, Sarah; Kliwicki, Sebastian; König, Barbara; Kusumi, Ichiro; Lackner, Nina; Laje, Gonzalo; Landén, Mikael; Lavebratt, Catharina; Leboyer, Marion; Leckband, Susan G; López Jaramillo, Carlos A; MacQueen, Glenda; Manchia, Mirko; Martinsson, Lina; Mattheisen, Manuel; McCarthy, Michael J; McElroy, Susan L; Mitjans, Marina; Mondimore, Francis M; Monteleone, Palmiero; Nievergelt, Caroline M; Ösby, Urban; Ozaki, Norio; Perlis, Roy H; Pfennig, Andrea; Reich-Erkelenz, Daniela; Rouleau, Guy A; Schofield, Peter R; Schubert, K Oliver; Schweizer, Barbara W; Seemüller, Florian; Severino, Giovanni; Shekhtman, Tatyana; Shilling, Paul D; Shimoda, Kazutaka; Simhandl, Christian; Slaney, Claire M; Smoller, Jordan W; Squassina, Alessio; Stamm, Thomas J; Stopkova, Pavla; Tighe, Sarah K; Tortorella, Alfonso; Turecki, Gustavo; Volkert, Julia; Witt, Stephanie H; Wright, Adam J; Young, L Trevor; Zandi, Peter P; Potash, James B; DePaulo, J Raymond; Bauer, Michael; Reininghaus, Eva; Novák, Tomáš; Aubry, Jean-Michel; Maj, Mario; Baune, Bernhard T; Mitchell, Philip B; Vieta, Eduard; Frye, Mark A; Rybakowski, Janusz K; Kuo, Po-Hsiu; Kato, Tadafumi; Grigoroiu-Serbanescu, Maria; Reif, Andreas; Del Zompo, Maria; Bellivier, Frank; Schalling, Martin; Wray, Naomi R; Kelsoe, John R; Alda, Martin; McMahon, Francis J; Schulze, Thomas G; Rietschel, Marcella; Nöthen, Markus M; Cichon, Sven

2018-01-01

Bipolar disorder (BD) is a common, highly heritable neuropsychiatric disease characterized by recurrent episodes of mania and depression. Lithium is the best-established long-term treatment for BD, even though individual response is highly variable. Evidence suggests that some of this variability has a genetic basis. This is supported by the largest genome-wide association study (GWAS) of lithium response to date conducted by the International Consortium on Lithium Genetics (ConLiGen). Recently, we performed the first genome-wide analysis of the involvement of miRNAs in BD and identified nine BD-associated miRNAs. However, it is unknown whether these miRNAs are also associated with lithium response in BD. In the present study, we therefore tested whether common variants at these nine candidate miRNAs contribute to the variance in lithium response in BD. Furthermore, we systematically analyzed whether any other miRNA in the genome is implicated in the response to lithium. For this purpose, we performed gene-based tests for all known miRNA coding genes in the ConLiGen GWAS dataset ( n = 2,563 patients) using a set-based testing approach adapted from the versatile gene-based test for GWAS (VEGAS2). In the candidate approach, miR-499a showed a nominally significant association with lithium response, providing some evidence for involvement in both development and treatment of BD. In the genome-wide miRNA analysis, 71 miRNAs showed nominally significant associations with the dichotomous phenotype and 106 with the continuous trait for treatment response. A total of 15 miRNAs revealed nominal significance in both phenotypes with miR-633 showing the strongest association with the continuous trait ( p = 9.80E-04) and miR-607 with the dichotomous phenotype ( p = 5.79E-04). No association between miRNAs and treatment response to lithium in BD in either of the tested conditions withstood multiple testing correction. Given the limited power of our study, the investigation of miRNAs in larger GWAS samples of BD and lithium response is warranted.

Fitting of dynamic recurrent neural network models to sensory stimulus-response data.

PubMed

Doruk, R Ozgur; Zhang, Kechen

2018-06-02

We present a theoretical study aiming at model fitting for sensory neurons. Conventional neural network training approaches are not applicable to this problem due to lack of continuous data. Although the stimulus can be considered as a smooth time-dependent variable, the associated response will be a set of neural spike timings (roughly the instants of successive action potential peaks) that have no amplitude information. A recurrent neural network model can be fitted to such a stimulus-response data pair by using the maximum likelihood estimation method where the likelihood function is derived from Poisson statistics of neural spiking. The universal approximation feature of the recurrent dynamical neuron network models allows us to describe excitatory-inhibitory characteristics of an actual sensory neural network with any desired number of neurons. The stimulus data are generated by a phased cosine Fourier series having a fixed amplitude and frequency but a randomly shot phase. Various values of amplitude, stimulus component size, and sample size are applied in order to examine the effect of the stimulus to the identification process. Results are presented in tabular and graphical forms at the end of this text. In addition, to demonstrate the success of this research, a study involving the same model, nominal parameters and stimulus structure, and another study that works on different models are compared to that of this research.

Active State Model for Autonomous Systems

NASA Technical Reports Server (NTRS)

Park, Han; Chien, Steve; Zak, Michail; James, Mark; Mackey, Ryan; Fisher, Forest

2003-01-01

The concept of the active state model (ASM) is an architecture for the development of advanced integrated fault-detection-and-isolation (FDI) systems for robotic land vehicles, pilotless aircraft, exploratory spacecraft, or other complex engineering systems that will be capable of autonomous operation. An FDI system based on the ASM concept would not only provide traditional diagnostic capabilities, but also integrate the FDI system under a unified framework and provide mechanism for sharing of information between FDI subsystems to fully assess the overall health of the system. The ASM concept begins with definitions borrowed from psychology, wherein a system is regarded as active when it possesses self-image, self-awareness, and an ability to make decisions itself, such that it is able to perform purposeful motions and other transitions with some degree of autonomy from the environment. For an engineering system, self-image would manifest itself as the ability to determine nominal values of sensor data by use of a mathematical model of itself, and selfawareness would manifest itself as the ability to relate sensor data to their nominal values. The ASM for such a system may start with the closed-loop control dynamics that describe the evolution of state variables. As soon as this model was supplemented with nominal values of sensor data, it would possess self-image. The ability to process the current sensor data and compare them with the nominal values would represent self-awareness. On the basis of self-image and self-awareness, the ASM provides the capability for self-identification, detection of abnormalities, and self-diagnosis.

Robust Temperature Control of a Thermoelectric Cooler via μ -Synthesis

NASA Astrophysics Data System (ADS)

Kürkçü, Burak; Kasnakoğlu, Coşku

2018-02-01

In this work robust temperature control of a thermoelectric cooler (TEC) via μ -synthesis is studied. An uncertain dynamical model for the TEC that is suitable for robust control methods is derived. The model captures variations in operating point due to current, load and temperature changes. A temperature controller is designed utilizing μ -synthesis, a powerful method guaranteeing robust stability and performance. For comparison two well-known control methods, namely proportional-integral-derivative (PID) and internal model control (IMC), are also realized to benchmark the proposed approach. It is observed that the stability and performance on the nominal model are satisfactory for all cases. On the other hand, under perturbations the responses of PID and IMC deteriorate and even become unstable. In contrast, the μ -synthesis controller succeeds in keeping system stability and achieving good performance under all perturbations within the operating range, while at the same time providing good disturbance rejection.

Application of Strength Requirements to Complex Loading Scenarios

NASA Technical Reports Server (NTRS)

England, Scott; Rajulu, Sudhakar

2016-01-01

NASA's endeavors in human spaceflight rely on extensive volumes of human-systems integration requirements to ensure mission success. These requirements protect for space hardware accommodation for the full range of potential crewmembers, but cannot cover every possible action and contingency in detail. This study was undertaken in response to questions from various strength requirement users who were unclear how to apply idealized strength requirements that did not map well to the complex loading scenarios that crewmembers would encounter. Three of the most commonly occurring questions from stakeholders were selected to be investigated with human testing and human modeling. Preliminary findings indicate deviation from nominal postures can affect strength requirement compliance positively or negatively, depending on the nature of the deviation. Human modeling offers some avenues for quickly addressing requirement verification questions, but is limited by the fidelity of the model and environment.

Occupant Protection during Orion Crew Exploration Vehicle Landings

NASA Technical Reports Server (NTRS)

Gernhardt, Michael L.; Jones, J. A.; Granderson, B. K.; Somers, J. T.

2009-01-01

The constellation program is evaluating current vehicle design capabilities for nominal water landings and contingency land landings of the Orion Crew Exploration vehicle. The Orion Landing Strategy tiger team was formed to lead the technical effort for which associated activities include the current vehicle design, susceptibility to roll control and tip over, reviewing methods for assessing occupant injury during ascent / aborts /landings, developing an alternate seat/attenuation design solution which improves occupant protection and operability, and testing the seat/attenuation system designs to ensure valid results. The EVA physiology, systems and Performance (EPSP) project is leading the effort under the authority of the Tiger Team Steering committee to develop, verify, validate and accredit biodynamics models using a variety of crash and injury databases including NASCAR, Indy Car and military aircraft. The validated biodynamics models will be used by the Constellation program to evaluate a variety of vehicle, seat and restraint designs in the context of multiple nominal and off-nominal landing scenarios. The models will be used in conjunction with Acceptable Injury Risk definitions to provide new occupant protection requirements for the Constellation Program.

Characterization of nonGaussian atmospheric turbulence for prediction of aircraft response statistics

NASA Technical Reports Server (NTRS)

Mark, W. D.

1977-01-01

Mathematical expressions were derived for the exceedance rates and probability density functions of aircraft response variables using a turbulence model that consists of a low frequency component plus a variance modulated Gaussian turbulence component. The functional form of experimentally observed concave exceedance curves was predicted theoretically, the strength of the concave contribution being governed by the coefficient of variation of the time fluctuating variance of the turbulence. Differences in the functional forms of response exceedance curves and probability densities also were shown to depend primarily on this same coefficient of variation. Criteria were established for the validity of the local stationary assumption that is required in the derivations of the exceedance curves and probability density functions. These criteria are shown to depend on the relative time scale of the fluctuations in the variance, the fluctuations in the turbulence itself, and on the nominal duration of the relevant aircraft impulse response function. Metrics that can be generated from turbulence recordings for testing the validity of the local stationary assumption were developed.

Strategic Control over Extent and Timing of Distractor-Based Response Activation

ERIC Educational Resources Information Center

Jost, Kerstin; Wendt, Mike; Luna-Rodriguez, Aquiles; Löw, Andreas; Jacobsen, Thomas

2017-01-01

In choice reaction time (RT) tasks, performance is often influenced by the presence of nominally irrelevant stimuli, referred to as distractors. Recent research provided evidence that distractor processing can be adjusted to the utility of the distractors: Distractors predictive of the upcoming target/response were more attended to and also…

Orbit Stability of OSIRIS-REx in the Vicinity of Bennu Using a High-Fidelity Solar Radiation Model

NASA Technical Reports Server (NTRS)

Williams, Trevor W.; Hughes, Kyle M.; Mashiku, Alinda K.; Longuski, James M.

2015-01-01

Solar radiation pressure is one of the largest perturbing forces on the OSIRISRex trajectory as it orbits the asteroid Bennu. In this work, we investigate how forces due to solar radiation perturb the OSIRIS-REx trajectory in a high-fidelity model. The model accounts for Bennu's non-spherical gravity field, third-body gravity forces from the Sun and Jupiter, as well as solar radiation forces acting on a simplified spacecraft model. Such high-fidelity simulations indicate significant solar radiation pressure perturbations from the nominal orbit. Modifications to the initial design of the nominal orbit are found using a variation of parameters approach that reduce the perturbation in eccentricity by a factor of one-half.

77 FR 24268 - Internal Revenue Service Advisory Council (IRSAC); Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-23

... interest in assuring that women and men, members of all races and national origins, and individuals with... Professional Responsibility (OPR). Members are not paid for their services. However, travel expenses for...

Role of exposure mode in the bioavailability of triphenyl phosphate to aquatic organisms

USGS Publications Warehouse

Huckins, James N.; Fairchild, James F.; Boyle, Terence P.

1991-01-01

A laboratory study was conducted to investigate the role of the route of triphenyl phosphate (TPP) entry on its aquatic bioavailability and acute biological effects. Three TPP treatments were used for exposures of fish and invertebrates. These consisted of TPP dosed directly into water with and without clean sediment and TPP spiked onto sediment prior to aqueous exposures. Results of static acute toxicity tests (no sediment) were 0.78 mg/L (96-h LC50) for bluegill, 0.36 mg/L (48-h EC50) for midge, and 0.25 mg/L (96-h EC50) for scud. At 24 h, the sediment (1.1% organic carbon)/water partition coefficient (Kp) for TPP was 112. Use of this partition coefficient model to predict the sediment-mediated reduction of TPP concentration in water during toxicity tests resulted in a value that was only 10% less than the nominal value. However, the required nominal concentration of TPP to cause acute toxicity responses in test organisms was significantly higher than the predicted value by the model for both clay and soil-derived sediment. Direct spiking of TPP to soil minimized TPP bioavailability. Data from parallel experiments designed to track TPP residues in water through time suggest that sorption kinetics control residue bioavailability in the initial 24 h of exposure and may account for observed differences in LC50 and EC50 values from the sediment treatments.

NSF Director to resign

NASA Astrophysics Data System (ADS)

Richman, Barbara T.

Edward A. Knapp, director of the National Science Foundation (NSF) since late 1982, will resign his post later this year to return to research at the Los Alamos National Laboratory. President Ronald Reagan has announced his intention to nominate Erich Bloch, vice president for technical personnel development at the IBM Corp., as Knapp's successor.Following formal nomination by President Reagan, the Senate must confirm Bloch as NSF director. If Bloch is confirmed, he is likely to bring to NSF the greater emphasis on engineering that the agency has sought in response to requests from Congress and the engineering community during the last year.

James B. Edwards nomination. Hearing before the Committee on Energy and Natural Resources, United States Senate, Ninety-Seventh Congress, First Session, January 12, 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

Thirteen witnesses spoke at a January 12, 1981 hearing on the nomination of James B. Edwards for the position of Secretary of Energy. They reviewed Gov. Edwards' career and qualifications in light of US economic and energy needs. The senators of eight states emphasized the urgency of appropriate energy policies. Their statements are followed by the comments and responses of the nominee. Further testimony was given by representatives of the Democratic party, nuclear- and fusion-energy proponents, and the Environmental Policy Center. (DCK)

Temporal Associations of Popularity and Alcohol Use Among Middle School Students

PubMed Central

Tucker, Joan S.; Miles, Jeremy N. V.; D’Amico, Elizabeth J.; Zhou, Annie J.; Green, Harold D.; Shih, Regina A.

2012-01-01

Purpose The goal of this study is to better understand the longitudinal cross-lagged associations between popularity, assessed through self-rating and peer nominations, and alcohol use among middle school students. Methods The analytic sample is 1,835 6th–8th grade students who were initially recruited from three California middle schools and surveyed in the fall and spring semesters of two academic years. Students reported on their background characteristics, past month alcohol use, and perceived popularity. Additionally, students provided school-based friendship nominations, which were used to calculate peer-nominated popularity. A cross-lagged regression approach within a structural equation modeling framework was used to examine the longitudinal relationship between popularity (self-rated and peer-nominated) and alcohol use. Results There was a statistically significant (p = 0.024) association between peer-nominated popularity and the probability of alcohol consumption at the subsequent survey, but not vice versa. Our results suggest that in a scenario where 8% of students are past month drinkers, each increase of 5 friendship nominations is associated with a 30% greater risk of being a current drinker at the next wave. We found no evidence of longitudinal associations between past month alcohol consumption and self-rated popularity. Conclusions Popularity is a risk factor for drinking during the middle school years, with peer-nominated popularity being more predictive of use than self-perceptions of popularity. To inform alcohol prevention efforts for middle school students, additional research is needed to better understand why adolescents with a larger number of school-based friendship ties are more inclined to drink. PMID:23260843

Structural characterization and viscoelastic constitutive modeling of skin.

PubMed

Sherman, Vincent R; Tang, Yizhe; Zhao, Shiteng; Yang, Wen; Meyers, Marc A

2017-04-15

A fascinating material, skin has a tensile response which exhibits an extended toe region of minimal stress up to nominal strains that, in some species, exceed 1, followed by significant stiffening until a roughly linear region. The large toe region has been attributed to its unique structure, consisting of a network of curved collagen fibers. Investigation of the structure of rabbit skin reveals that it consists of layers of wavy fibers, each one with a characteristic orientation. Additionally, the existence of two preferred layer orientations is suggested based on the results of small angle X-ray scattering. These observations are used to construct a viscoelastic model consisting of collagen in two orientations, which leads to an in-plane anisotropic response. The structure-based model presented incorporates the elastic straightening and stretching of fibrils, their rotation towards the tensile axis, and the viscous effects which occur in the matrix of the skin due to interfibrillar and interlamellar sliding. The model is shown to effectively capture key features which dictate the mechanical response of skin. Examination by transmission and scanning electron microscopy of rabbit dermis enabled the identification of the key elements in its structure. The organization of collagen fibrils into flat fibers was identified and incorporated into a constitutive model that reproduces the mechanical response of skin. This enhanced quantitative predictive capability can be used in the design of synthetic skin and skin-like structures. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Atrioventricular and ventricular-to-ventricular programming in patients with cardiac resynchronization therapy: results from ALTITUDE.

PubMed

Steinberg, Benjamin A; Wehrenberg, Scott; Jackson, Kevin P; Hayes, David L; Varma, Niraj; Powell, Brian D; Day, John D; Frazier-Mills, Camille G; Stein, Kenneth M; Jones, Paul W; Piccini, Jonathan P

2015-12-01

Cardiac resynchronization therapy (CRT) improves outcomes in patients with heart failure, yet response rates are variable. We sought to determine whether physician-specified CRT programming was associated with improved outcomes. Using data from the ALTITUDE remote follow-up cohort, we examined sensed atrioventricular (AV) and ventricular-to-ventricular (VV) programming and their associated outcomes in patients with de novo CRT from 2009-2010. Outcomes included arrhythmia burden, left ventricular (LV) pacing, and all-cause mortality at 4 years. We identified 5709 patients with de novo CRT devices; at the time of implant, 34% (n = 1959) had entirely nominal settings programmed, 40% (n = 2294) had only AV timing adjusted, 11% (n = 604) had only VV timing adjusted, and 15% (n = 852) had both AV and VV adjusted from nominal programming. Suboptimal LV pacing (<95%) during follow-up was similar across groups; however, the proportion with atrial fibrillation (AF) burden >5% was lowest in the AV-only adjusted group (17.9%) and highest in the nominal (27.7%) and VV-only adjusted (28.3%) groups. Adjusted all-cause mortality was significantly higher among patients with non-nominal AV delay >120 vs. <120 ms (adjusted heart rate (HR) 1.28, p = 0.008) but similar when using the 180-ms cutoff (adjusted HR 1.13 for >180 vs. ≤180 ms, p = 0.4). Nominal settings for de novo CRT implants are frequently altered, most commonly the AV delay. There is wide variability in reprogramming. Patients with nominal or AV-only adjustments appear to have favorable pacing and arrhythmia outcomes. Sensed AV delays less than 120 ms are associated with improved survival.

Modeling to predict pilot performance during CDTI-based in-trail following experiments

NASA Technical Reports Server (NTRS)

Sorensen, J. A.; Goka, T.

1984-01-01

A mathematical model was developed of the flight system with the pilot using a cockpit display of traffic information (CDTI) to establish and maintain in-trail spacing behind a lead aircraft during approach. Both in-trail and vertical dynamics were included. The nominal spacing was based on one of three criteria (Constant Time Predictor; Constant Time Delay; or Acceleration Cue). This model was used to simulate digitally the dynamics of a string of multiple following aircraft, including response to initial position errors. The simulation was used to predict the outcome of a series of in-trail following experiments, including pilot performance in maintaining correct longitudinal spacing and vertical position. The experiments were run in the NASA Ames Research Center multi-cab cockpit simulator facility. The experimental results were then used to evaluate the model and its prediction accuracy. Model parameters were adjusted, so that modeled performance matched experimental results. Lessons learned in this modeling and prediction study are summarized.

Thermal barrier coating life prediction model development

NASA Technical Reports Server (NTRS)

Demasi, J. T.; Sheffler, K. D.

1986-01-01

The objective of this program is to establish a methodology to predict Thermal Barrier Coating (TBC) life on gas turbine engine components. The approach involves experimental life measurement coupled with analytical modeling of relevant degradation modes. The coating being studied is a flight qualified two layer system, designated PWA 264, consisting of a nominal ten mil layer of seven percent yttria partially stabilized zirconia plasma deposited over a nominal five mil layer of low pressure plasma deposited NiCoCrAlY. Thermal barrier coating degradation modes being investigated include: thermomechanical fatigue, oxidation, erosion, hot corrosion, and foreign object damage.

Modeling of the interest rate policy of the central bank of Russia

NASA Astrophysics Data System (ADS)

Shelomentsev, A. G.; Berg, D. B.; Detkov, A. A.; Rylova, A. P.

2017-11-01

This paper investigates interactions among money supply, exchange rates, inflation, and nominal interest rates, which are regulating parameters of the Central bank policy. The study is based on the data received from Russian source in 2002-2016. The major findings are 1) the interest rate demonstrates almost no relation with inflation; 2) ties of money supply and the nominal interest rate are strong; 3) money supply and inflation show meaningful relations only in comparison to their growth rates. We have developed a dynamic model, which can be used in forecasting of macroeconomic processes.

Prediction of different ovarian responses using anti-Müllerian hormone following a long agonist treatment protocol for IVF.

PubMed

Heidar, Z; Bakhtiyari, M; Mirzamoradi, M; Zadehmodarres, S; Sarfjoo, F S; Mansournia, M A

2015-09-01

The purpose of this study was to predict the poor and excessive ovarian response using anti-Müllerian hormone (AMH) levels following a long agonist protocol in IVF candidates. Through a prospective cohort study, the type of relationship and appropriate scale for AMH were determined using the fractional polynomial regression. To determine the effect of AMH on the outcomes of ovarian stimulation and different ovarian responses, the multi-nominal and negative binomial regression models were fitted using backward stepwise method. The ovarian response of study subject who entered a standard long-term treatment cycle with GnRH agonist was evaluated using prediction model, separately and in combined models with (ROC) curves. The use of standard long-term treatments with GnRH agonist led to positive pregnancy test results in 30% of treated patients. With each unit increase in the log of AMH, the odds ratio of having poor response compared to normal response decreases by 64% (OR 0.36, 95% CI 0.19-0.68). Also the results of negative binomial regression model indicated that for one unit increase in the log of AMH blood levels, the odds of releasing an oocyte increased 24% (OR 1.24, 95% CI 1.14-1.35). The optimal cut-off points of AMH for predicting excessive and poor ovarian responses were 3.4 and 1.2 ng/ml, respectively, with area under curves of 0.69 (0.60-0.77) and 0.76 (0.66-0.86), respectively. By considering the age of the patient undergoing infertility treatment as a variable affecting ovulation, use of AMH levels showed to be a good test to discriminate between different ovarian responses.

Non-ignorable missingness item response theory models for choice effects in examinee-selected items.

PubMed

Liu, Chen-Wei; Wang, Wen-Chung

2017-11-01

Examinee-selected item (ESI) design, in which examinees are required to respond to a fixed number of items in a given set, always yields incomplete data (i.e., when only the selected items are answered, data are missing for the others) that are likely non-ignorable in likelihood inference. Standard item response theory (IRT) models become infeasible when ESI data are missing not at random (MNAR). To solve this problem, the authors propose a two-dimensional IRT model that posits one unidimensional IRT model for observed data and another for nominal selection patterns. The two latent variables are assumed to follow a bivariate normal distribution. In this study, the mirt freeware package was adopted to estimate parameters. The authors conduct an experiment to demonstrate that ESI data are often non-ignorable and to determine how to apply the new model to the data collected. Two follow-up simulation studies are conducted to assess the parameter recovery of the new model and the consequences for parameter estimation of ignoring MNAR data. The results of the two simulation studies indicate good parameter recovery of the new model and poor parameter recovery when non-ignorable missing data were mistakenly treated as ignorable. © 2017 The British Psychological Society.

76 FR 21098 - Internal Revenue Service Advisory Council (IRSAC); Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-14

... Treasury and IRS policies. ``The IRS has special interest in assuring that women and men, members of all... Professional Responsibility (OPR). Members are not paid for their services. However, travel expenses for...

Nominate a Codex MRL

EPA Pesticide Factsheets

The Codex Committee on Pesticide Residues (CCPR) is responsible for establishing maximum residue limits (MRLs) for pesticide residues in specific food items or in groups of food for Codex. Learn how to submit a request for a CODEX MRL.

Robust time and frequency domain estimation methods in adaptive control

NASA Technical Reports Server (NTRS)

Lamaire, Richard Orville

1987-01-01

A robust identification method was developed for use in an adaptive control system. The type of estimator is called the robust estimator, since it is robust to the effects of both unmodeled dynamics and an unmeasurable disturbance. The development of the robust estimator was motivated by a need to provide guarantees in the identification part of an adaptive controller. To enable the design of a robust control system, a nominal model as well as a frequency-domain bounding function on the modeling uncertainty associated with this nominal model must be provided. Two estimation methods are presented for finding parameter estimates, and, hence, a nominal model. One of these methods is based on the well developed field of time-domain parameter estimation. In a second method of finding parameter estimates, a type of weighted least-squares fitting to a frequency-domain estimated model is used. The frequency-domain estimator is shown to perform better, in general, than the time-domain parameter estimator. In addition, a methodology for finding a frequency-domain bounding function on the disturbance is used to compute a frequency-domain bounding function on the additive modeling error due to the effects of the disturbance and the use of finite-length data. The performance of the robust estimator in both open-loop and closed-loop situations is examined through the use of simulations.

Modeling misregistration and related effects on multispectral classification

NASA Technical Reports Server (NTRS)

Billingsley, F. C.

1981-01-01

The effects of misregistration on the multispectral classification accuracy when the scene registration accuracy is relaxed from 0.3 to 0.5 pixel are investigated. Noise, class separability, spatial transient response, and field size are considered simultaneously with misregistration in their effects on accuracy. Any noise due to the scene, sensor, or to the analog/digital conversion, causes a finite fraction of the measurements to fall outside of the classification limits, even within nominally uniform fields. Misregistration causes field borders in a given band or set of bands to be closer than expected to a given pixel, causing additional pixels to be misclassified due to the mixture of materials in the pixel. Simplified first order models of the various effects are presented, and are used to estimate the performance to be expected.

An approach to verification and validation of a reliable multicasting protocol: Extended Abstract

NASA Technical Reports Server (NTRS)

Callahan, John R.; Montgomery, Todd L.

1995-01-01

This paper describes the process of implementing a complex communications protocol that provides reliable delivery of data in multicast-capable, packet-switching telecommunication networks. The protocol, called the Reliable Multicasting Protocol (RMP), was developed incrementally using a combination of formal and informal techniques in an attempt to ensure the correctness of its implementation. Our development process involved three concurrent activities: (1) the initial construction and incremental enhancement of a formal state model of the protocol machine; (2) the initial coding and incremental enhancement of the implementation; and (3) model-based testing of iterative implementations of the protocol. These activities were carried out by two separate teams: a design team and a V&V team. The design team built the first version of RMP with limited functionality to handle only nominal requirements of data delivery. This initial version did not handle off-nominal cases such as network partitions or site failures. Meanwhile, the V&V team concurrently developed a formal model of the requirements using a variant of SCR-based state tables. Based on these requirements tables, the V&V team developed test cases to exercise the implementation. In a series of iterative steps, the design team added new functionality to the implementation while the V&V team kept the state model in fidelity with the implementation. This was done by generating test cases based on suspected errant or off-nominal behaviors predicted by the current model. If the execution of a test in the model and implementation agreed, then the test either found a potential problem or verified a required behavior. However, if the execution of a test was different in the model and implementation, then the differences helped identify inconsistencies between the model and implementation. In either case, the dialogue between both teams drove the co-evolution of the model and implementation. We have found that this interactive, iterative approach to development allows software designers to focus on delivery of nominal functionality while the V&V team can focus on analysis of off nominal cases. Testing serves as the vehicle for keeping the model and implementation in fidelity with each other. This paper describes (1) our experiences in developing our process model; and (2) three example problems found during the development of RMP. Although RMP has provided our research effort with a rich set of test cases, it also has practical applications within NASA. For example, RMP is being considered for use in the NASA EOSDIS project due to its significant performance benefits in applications that need to replicate large amounts of data to many network sites.

30 CFR 285.213 - What must I submit in response to a Request for Interest or a Call for Information and Nominations?

Code of Federal Regulations, 2011 CFR

2011-07-01

... OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE ENERGY ALTERNATE USES OF EXISTING FACILITIES ON THE OUTER CONTINENTAL SHELF Issuance of OCS Renewable Energy Leases Competitive Lease Process § 285.213 What must I submit in response to a Request for...

Asymmetric Responses of Primary Productivity to Altered Precipitation Simulated by Land Surface Models across Three Long-term Grassland Sites

NASA Astrophysics Data System (ADS)

Wu, D.; Ciais, P.; Viovy, N.; Knapp, A.; Wilcox, K.; Bahn, M.; Smith, M. D.; Ito, A.; Arneth, A.; Harper, A. B.; Ukkola, A.; Paschalis, A.; Poulter, B.; Peng, C.; Reick, C. H.; Hayes, D. J.; Ricciuto, D. M.; Reinthaler, D.; Chen, G.; Tian, H.; Helene, G.; Zscheischler, J.; Mao, J.; Ingrisch, J.; Nabel, J.; Pongratz, J.; Boysen, L.; Kautz, M.; Schmitt, M.; Krohn, M.; Zeng, N.; Meir, P.; Zhang, Q.; Zhu, Q.; Hasibeder, R.; Vicca, S.; Sippel, S.; Dangal, S. R. S.; Fatichi, S.; Sitch, S.; Shi, X.; Wang, Y.; Luo, Y.; Liu, Y.; Piao, S.

2017-12-01

Changes in precipitation variability including the occurrence of extreme events strongly influence plant growth in grasslands. Field measurements of aboveground net primary production (ANPP) in temperate grasslands suggest a positive asymmetric response with wet years resulting in ANPP gains larger than ANPP declines in dry years. Whether land surface models used for historical simulations and future projections of the coupled carbon-water system in grasslands are capable to simulate such non-symmetrical ANPP responses remains an important open research question. In this study, we evaluate the simulated responses of grassland primary productivity to altered precipitation with fourteen land surface models at the three sites of Colorado Shortgrass Steppe (SGS), Konza prairie (KNZ) and Stubai Valley meadow (STU) along a rainfall gradient from dry to wet. Our results suggest that: (i) Gross primary production (GPP), NPP, ANPP and belowground NPP (BNPP) show nonlinear response curves (concave-down) in all the models, but with different curvatures and mean values. In contrast across the sites, primary production increases and then saturates along increasing precipitation with a flattening at the wetter site. (ii) Slopes of spatial relationships between modeled primary production and precipitation are steeper than the temporal slopes (obtained from inter-annual variations). (iii) Asymmetric responses under nominal precipitation range with modeled inter-annual primary production show large uncertainties, and model-ensemble median generally suggests negative asymmetry (greater declines in dry years than increases in wet years) across the three sites. (iv) Primary production at the drier site is predicted to more sensitive to precipitation compared to wetter site, and median sensitivity consistently indicates greater negative impacts of reduced precipitation than positive effects of increased precipitation under extreme conditions. This study implies that most models overemphasize the drought effects or underestimate the watering impacts on primary production in the normal-state, with the direct consequence that carbon-water interactions need to be improved in future model generations with improved mechanistic representations.

Vibroacoustic Model Validation for a Curved Honeycomb Composite Panel

NASA Technical Reports Server (NTRS)

Buehrle, Ralph D.; Robinson, Jay H.; Grosveld, Ferdinand W.

2001-01-01

Finite element and boundary element models are developed to investigate the vibroacoustic response of a curved honeycomb composite sidewall panel. Results from vibroacoustic tests conducted in the NASA Langley Structural Acoustic Loads and Transmission facility are used to validate the numerical predictions. The sidewall panel is constructed from a flexible honeycomb core sandwiched between carbon fiber reinforced composite laminate face sheets. This type of construction is being used in the development of an all-composite aircraft fuselage. In contrast to conventional rib-stiffened aircraft fuselage structures, the composite panel has nominally uniform thickness resulting in a uniform distribution of mass and stiffness. Due to differences in the mass and stiffness distribution, the noise transmission mechanisms for the composite panel are expected to be substantially different from those of a conventional rib-stiffened structure. The development of accurate vibroacoustic models will aide in the understanding of the dominant noise transmission mechanisms and enable optimization studies to be performed that will determine the most beneficial noise control treatments. Finite element and boundary element models of the sidewall panel are described. Vibroacoustic response predictions are presented for forced vibration input and the results are compared with experimental data.

Shorebird Migration Patterns in Response to Climate Change: A Modeling Approach

NASA Technical Reports Server (NTRS)

Smith, James A.

2010-01-01

The availability of satellite remote sensing observations at multiple spatial and temporal scales, coupled with advances in climate modeling and information technologies offer new opportunities for the application of mechanistic models to predict how continental scale bird migration patterns may change in response to environmental change. In earlier studies, we explored the phenotypic plasticity of a migratory population of Pectoral sandpipers by simulating the movement patterns of an ensemble of 10,000 individual birds in response to changes in stopover locations as an indicator of the impacts of wetland loss and inter-annual variability on the fitness of migratory shorebirds. We used an individual based, biophysical migration model, driven by remotely sensed land surface data, climate data, and biological field data. Mean stop-over durations and stop-over frequency with latitude predicted from our model for nominal cases were consistent with results reported in the literature and available field data. In this study, we take advantage of new computing capabilities enabled by recent GP-GPU computing paradigms and commodity hardware (general purchase computing on graphics processing units). Several aspects of our individual based (agent modeling) approach lend themselves well to GP-GPU computing. We have been able to allocate compute-intensive tasks to the graphics processing units, and now simulate ensembles of 400,000 birds at varying spatial resolutions along the central North American flyway. We are incorporating additional, species specific, mechanistic processes to better reflect the processes underlying bird phenotypic plasticity responses to different climate change scenarios in the central U.S.

Skipped Stage Modeling and Testing of the CPAS Main Parachutes

NASA Technical Reports Server (NTRS)

Varela, Jose G.; Ray, Eric S.

2013-01-01

The Capsule Parachute Assembly System (CPAS) has undergone the transition from modeling a skipped stage event using a simulation that treats a cluster of parachutes as a single composite canopy to the capability of simulating each parachute individually. This capability along with data obtained from skipped stage flight tests has been crucial in modeling the behavior of a skipping canopy as well as the crowding effect on non-skipping ("lagging") neighbors. For the finite mass inflation of CPAS Main parachutes, the cluster is assumed to inflate nominally through the nominal fill time, at which point the skipping parachute continues inflating. This sub-phase modeling method was used to reconstruct three flight tests involving skipped stages. Best fit inflation parameters were determined for both the skipping and lagging canopies.

Optimal motion planning for collision avoidance of mobile robots in non-stationary environments

NASA Technical Reports Server (NTRS)

Kyriakopoulos, K. J.; Saridis, G. N.

1992-01-01

An optimal control formulation of the problem of collision avoidance of mobile robots moving in general terrains containing moving obstacles is presented. A dynamic model of the mobile robot and the dynamic constraints are derived. Collision avoidance is guaranteed if the minimum distance between the robot and the object is nonzero. A nominal trajectory is assumed to be known from off-line planning. The main idea is to change the velocity along the nominal trajectory so that collisions are avoided. Time consistency with the nominal plan is desirable. A numerical solution of the optimization problem is obtained. A perturbation control type of approach is used to update the optimal plan. Simulation results verify the value of the proposed strategy.

Nominal vs. actual supersaturation of solutions

NASA Astrophysics Data System (ADS)

Borisenko, Alexander

2018-03-01

Following the formalism of the Classical Nucleation Theory beyond the dilute solution approximation, this paper considers a difference between the actual solute supersaturation (given by the present-to-saturated solute activity ratio) and the nominal supersaturation (given by the present-to-saturated solute concentration ratio) due to formation of subcritical transient solute clusters, called heterophase fluctuations. Based on their distribution function, we introduce an algebraic equation of supersaturation that couples the nominal supersaturation of a binary metastable solution with its actual supersaturation and a function of the specific interface energy and temperature. The applicability of this approach is validated by comparison to simulation data [(Clouet et al., Phys. Rev. B 69, 064109 (2004)] on nucleation of Al3Zr and Al3Sc in model binary Al alloys.

Temporal associations of popularity and alcohol use among middle school students.

PubMed

Tucker, Joan S; Miles, Jeremy N V; D'Amico, Elizabeth J; Zhou, Annie J; Green, Harold D; Shih, Regina A

2013-01-01

The goal of this study is to better understand the longitudinal cross-lagged associations between popularity, assessed through self-rating and peer nominations, and alcohol use among middle school students. The analytical sample comprises 1,835 sixth- to eighth-grade students who were initially recruited from three California middle schools and surveyed in the fall and spring semesters of 2 academic years. Students reported on their background characteristics, past-month alcohol use, and perceived popularity. Additionally, students provided school-based friendship nominations, which were used to calculate peer-nominated popularity. A cross-lagged regression approach within a structural equation modeling framework was used to examine the longitudinal relationship between popularity (self-rated and peer-nominated) and alcohol use. There was a statistically significant (p = .024) association between peer-nominated popularity and the probability of alcohol consumption at the subsequent survey, but not vice versa. Our results suggest that in a scenario where 8% of students are past-month drinkers, each increase of five friendship nominations is associated with a 30% greater risk of being a current drinker at the next wave. We found no evidence of longitudinal associations between past-month alcohol consumption and self-rated popularity. Popularity is a risk factor for drinking during the middle school years, with peer-nominated popularity being more predictive of use than self-perceptions of popularity. To inform alcohol prevention efforts for middle school students, additional research is needed to better understand why adolescents with a larger number of school-based friendship ties are more inclined to drink. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

78 FR 21709 - Internal Revenue Service Advisory Council (IRSAC); Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-11

... IRS policies. The IRS has special interest in assuring that women and men, members of all races and... & Investment (W&I); and the Office of Professional Responsibility (OPR). Members are not paid for their...

Electrical and optical performance of mid-wavelength infrared InAsSb heterostructure detectors

NASA Astrophysics Data System (ADS)

Gomółka, Emilia; Kopytko, Małgorzata; Michalczewski, Krystian; Kubiszyn, Łukasz; Kebłowski, Artur; Gawron, Waldemar; Martyniuk, Piotr; Piotrowski, Józef; Rutkowski, Jarosław

2017-10-01

In this work we investigate the high-operating temperature performance of InAsSb/AlSb heterostructure detectors with cut-off wavelengths near 5 μm at 230 K. The devices have been fabricated with different type of the absorbing layer: nominally undoped absorber, and both n- and p-type doped. The results show that the device performance strongly depends on absorber layer doping. Generally, p-type absorber provides higher values of current responsivity than n-type absorber, but at the same time also higher values of dark current. The device with nominally undoped absorbing layer shows moderate values of both current responsivity and dark current. Resulting detectivities D° of non-immersed devices varies from 2×109 to 7×109 cmHz1/2/W at 230 K, which is easily achievable with a two stage thermoelectric cooler.

On the estimation algorithm used in adaptive performance optimization of turbofan engines

NASA Technical Reports Server (NTRS)

Espana, Martin D.; Gilyard, Glenn B.

1993-01-01

The performance seeking control algorithm is designed to continuously optimize the performance of propulsion systems. The performance seeking control algorithm uses a nominal model of the propulsion system and estimates, in flight, the engine deviation parameters characterizing the engine deviations with respect to nominal conditions. In practice, because of measurement biases and/or model uncertainties, the estimated engine deviation parameters may not reflect the engine's actual off-nominal condition. This factor has a necessary impact on the overall performance seeking control scheme exacerbated by the open-loop character of the algorithm. The effects produced by unknown measurement biases over the estimation algorithm are evaluated. This evaluation allows for identification of the most critical measurements for application of the performance seeking control algorithm to an F100 engine. An equivalence relation between the biases and engine deviation parameters stems from an observability study; therefore, it is undecided whether the estimated engine deviation parameters represent the actual engine deviation or whether they simply reflect the measurement biases. A new algorithm, based on the engine's (steady-state) optimization model, is proposed and tested with flight data. When compared with previous Kalman filter schemes, based on local engine dynamic models, the new algorithm is easier to design and tune and it reduces the computational burden of the onboard computer.

Identifying future models for delivering genetic services: a nominal group study in primary care

PubMed Central

Elwyn, Glyn; Edwards, Adrian; Iredale, Rachel; Davies, Peter; Gray, Jonathon

2005-01-01

Background To enable primary care medical practitioners to generate a range of possible service delivery models for genetic counselling services and critically assess their suitability. Methods Modified nominal group technique using in primary care professional development workshops. Results 37 general practitioners in Wales, United Kingdom too part in the nominal group process. The practitioners who attended did not believe current systems were sufficient to meet anticipated demand for genetic services. A wide range of different service models was proposed, although no single option emerged as a clear preference. No argument was put forward for genetic assessment and counselling being central to family practice, neither was there a voice for the view that the family doctor should become skilled at advising patients about predictive genetic testing and be able to counsel patients about the wider implications of genetic testing for patients and their family members, even for areas such as common cancers. Nevertheless, all the preferred models put a high priority on providing the service in the community, and often co-located in primary care, by clinicians who had developed expertise. Conclusion There is a need for a wider debate about how healthcare systems address individual concerns about genetic concerns and risk, especially given the increasing commercial marketing of genetic tests. PMID:15831099

Design of a Model Reference Adaptive Controller for an Unmanned Air Vehicle

NASA Technical Reports Server (NTRS)

Crespo, Luis G.; Matsutani, Megumi; Annaswamy, Anuradha M.

2010-01-01

This paper presents the "Adaptive Control Technology for Safe Flight (ACTS)" architecture, which consists of a non-adaptive controller that provides satisfactory performance under nominal flying conditions, and an adaptive controller that provides robustness under off nominal ones. The design and implementation procedures of both controllers are presented. The aim of these procedures, which encompass both theoretical and practical considerations, is to develop a controller suitable for flight. The ACTS architecture is applied to the Generic Transport Model developed by NASA-Langley Research Center. The GTM is a dynamically scaled test model of a transport aircraft for which a flight-test article and a high-fidelity simulation are available. The nominal controller at the core of the ACTS architecture has a multivariable LQR-PI structure while the adaptive one has a direct, model reference structure. The main control surfaces as well as the throttles are used as control inputs. The inclusion of the latter alleviates the pilot s workload by eliminating the need for cancelling the pitch coupling generated by changes in thrust. Furthermore, the independent usage of the throttles by the adaptive controller enables their use for attitude control. Advantages and potential drawbacks of adaptation are demonstrated by performing high fidelity simulations of a flight-validated controller and of its adaptive augmentation.

Delayed seismicity rate changes controlled by static stress transfer

USGS Publications Warehouse

Kroll, Kayla A.; Richards-Dinger, Keith B.; Dieterich, James H.; Cochran, Elizabeth S.

2017-01-01

On 15 June 2010, a Mw5.7 earthquake occurred near Ocotillo, California, in the Yuha Desert. This event was the largest aftershock of the 4 April 2010 Mw7.2 El Mayor-Cucapah (EMC) earthquake in this region. The EMC mainshock and subsequent Ocotillo aftershock provide an opportunity to test the Coulomb failure hypothesis (CFS). We explore the spatiotemporal correlation between seismicity rate changes and regions of positive and negative CFS change imparted by the Ocotillo event. Based on simple CFS calculations we divide the Yuha Desert into three subregions, one triggering zone and two stress shadow zones. We find the nominal triggering zone displays immediate triggering, one stress shadowed region experiences immediate quiescence, and the other nominal stress shadow undergoes an immediate rate increase followed by a delayed shutdown. We quantitatively model the spatiotemporal variation of earthquake rates by combining calculations of CFS change with the rate-state earthquake rate formulation of Dieterich (1994), assuming that each subregion contains a mixture of nucleation sources that experienced a CFS change of differing signs. Our modeling reproduces the observations, including the observed delay in the stress shadow effect in the third region following the Ocotillo aftershock. The delayed shadow effect occurs because of intrinsic differences in the amplitude of the rate response to positive and negative stress changes and the time constants for return to background rates for the two populations. We find that rate-state models of time-dependent earthquake rates are in good agreement with the observed rates and thus explain the complex spatiotemporal patterns of seismicity.

Delayed Seismicity Rate Changes Controlled by Static Stress Transfer

NASA Astrophysics Data System (ADS)

Kroll, Kayla A.; Richards-Dinger, Keith B.; Dieterich, James H.; Cochran, Elizabeth S.

2017-10-01

On 15 June 2010, a Mw5.7 earthquake occurred near Ocotillo, California, in the Yuha Desert. This event was the largest aftershock of the 4 April 2010 Mw7.2 El Mayor-Cucapah (EMC) earthquake in this region. The EMC mainshock and subsequent Ocotillo aftershock provide an opportunity to test the Coulomb failure hypothesis (CFS). We explore the spatiotemporal correlation between seismicity rate changes and regions of positive and negative CFS change imparted by the Ocotillo event. Based on simple CFS calculations we divide the Yuha Desert into three subregions, one triggering zone and two stress shadow zones. We find the nominal triggering zone displays immediate triggering, one stress shadowed region experiences immediate quiescence, and the other nominal stress shadow undergoes an immediate rate increase followed by a delayed shutdown. We quantitatively model the spatiotemporal variation of earthquake rates by combining calculations of CFS change with the rate-state earthquake rate formulation of Dieterich (1994), assuming that each subregion contains a mixture of nucleation sources that experienced a CFS change of differing signs. Our modeling reproduces the observations, including the observed delay in the stress shadow effect in the third region following the Ocotillo aftershock. The delayed shadow effect occurs because of intrinsic differences in the amplitude of the rate response to positive and negative stress changes and the time constants for return to background rates for the two populations. We find that rate-state models of time-dependent earthquake rates are in good agreement with the observed rates and thus explain the complex spatiotemporal patterns of seismicity.

Off-target model based OPC

NASA Astrophysics Data System (ADS)

Lu, Mark; Liang, Curtis; King, Dion; Melvin, Lawrence S., III

2005-11-01

Model-based Optical Proximity correction has become an indispensable tool for achieving wafer pattern to design fidelity at current manufacturing process nodes. Most model-based OPC is performed considering the nominal process condition, with limited consideration of through process manufacturing robustness. This study examines the use of off-target process models - models that represent non-nominal process states such as would occur with a dose or focus variation - to understands and manipulate the final pattern correction to a more process robust configuration. The study will first examine and validate the process of generating an off-target model, then examine the quality of the off-target model. Once the off-target model is proven, it will be used to demonstrate methods of generating process robust corrections. The concepts are demonstrated using a 0.13 μm logic gate process. Preliminary indications show success in both off-target model production and process robust corrections. With these off-target models as tools, mask production cycle times can be reduced.

Probabilistic risk assessment of the Space Shuttle. Phase 3: A study of the potential of losing the vehicle during nominal operation. Volume 2: Integrated loss of vehicle model

NASA Technical Reports Server (NTRS)

Fragola, Joseph R.; Maggio, Gaspare; Frank, Michael V.; Gerez, Luis; Mcfadden, Richard H.; Collins, Erin P.; Ballesio, Jorge; Appignani, Peter L.; Karns, James J.

1995-01-01

The application of the probabilistic risk assessment methodology to a Space Shuttle environment, particularly to the potential of losing the Shuttle during nominal operation is addressed. The different related concerns are identified and combined to determine overall program risks. A fault tree model is used to allocate system probabilities to the subsystem level. The loss of the vehicle due to failure to contain energetic gas and debris, to maintain proper propulsion and configuration is analyzed, along with the loss due to Orbiter, external tank failure, and landing failure or error.

Comprehensive evaluation of the Estrogen Receptor Alpha gene reveals further evidence for association with type 2 diabetes enriched for nephropathy in an African American population

PubMed Central

Keene, Keith L.; Mychaleckyj, Josyf C.; Smith, Shelly G.; Leak, Tennille S.; Perlegas, Peter S.; Langefeld, Carl D.; Herrington, David M.; Freedman, Barry I.; Rich, Stephen S.; Bowden, Donald W.; Sale, Michèle M.

2009-01-01

We previously investigated the estrogen receptor α gene (ESR1) as a positional candidate for type 2 diabetes (T2DM), and found evidence for association between the intron 1-intron 2 region of this gene and type 2 diabetes and/or nephropathy in an African American (AA) population. Our objective was to comprehensively evaluate variants across the entire ESR1 gene for association in AA with T2DM and End Stage Renal Disease (T2DM-ESRD). One hundred fifty SNPs in ESR1, spanning 476 kb, were genotyped in 577 AA individuals with T2DM-ESRD and 596 AA controls. Genotypic association tests for dominant, additive, and recessive models, and haplotypic association, were calculated using a χ2 statistic and corresponding P value. Thirty-one SNPs showed nominal evidence for association (P< 0.05) with T2DM-ESRD in one or more genotypic model. After correcting for multiple tests, promoter SNP rs11964281 (nominal P=0.000291, adjusted P=0.0289), and intron 4 SNPs rs1569788 (nominal P=0.000754, adjusted P=0.0278) and rs9340969 (nominal P=0.00109, adjusted P=0.0467) remained significant at experimentwise error rate (EER) P<0.05 for the dominant class of tests. Twenty-three of the thirty-one associated SNPs cluster within the intron 4-intron 6 region. Gender stratification revealed nominal evidence for association with 35 SNPs in females (352 cases; 306 controls) and seven SNPs in males (225 cases; 290 controls). We have identified a novel region of the ESR1 gene that may contain important functional polymorphisms in relation to susceptibility to T2DM and/or diabetic nephropathy. PMID:18305958

Comprehensive evaluation of the estrogen receptor alpha gene reveals further evidence for association with type 2 diabetes enriched for nephropathy in an African American population.

PubMed

Keene, Keith L; Mychaleckyj, Josyf C; Smith, Shelly G; Leak, Tennille S; Perlegas, Peter S; Langefeld, Carl D; Herrington, David M; Freedman, Barry I; Rich, Stephen S; Bowden, Donald W; Sale, Michèle M

2008-05-01

We previously investigated the estrogen receptor alpha gene (ESR1) as a positional candidate for type 2 diabetes (T2DM), and found evidence for association between the intron 1-intron 2 region of this gene and T2DM and/or nephropathy in an African American (AA) population. Our objective was to comprehensively evaluate variants across the entire ESR1 gene for association in AA with T2DM and end stage renal disease (T2DM-ESRD). One hundred fifty SNPs in ESR1, spanning 476 kb, were genotyped in 577 AA individuals with T2DM-ESRD and 596 AA controls. Genotypic association tests for dominant, additive, and recessive models, and haplotypic association, were calculated using a chi(2) statistic and corresponding P value. Thirty-one SNPs showed nominal evidence for association (P < 0.05) with T2DM-ESRD in one or more genotypic model. After correcting for multiple tests, promoter SNP rs11964281 (nominal P = 0.000291, adjusted P = 0.0289), and intron 4 SNPs rs1569788 (nominal P = 0.000754, adjusted P = 0.0278) and rs9340969 (nominal P = 0.00109, adjusted P = 0.0467) remained significant at experimentwise error rate (EER) P

Acoustic testing of a 1.5 pressure ratio low tip speed fan with a serrated rotor (QEP fan B scale model). [reduction of engine noise

NASA Technical Reports Server (NTRS)

Kazin, S. B.; Paas, J. E.; Minzner, W. R.

1973-01-01

A scale model of the bypass flow region of a 1.5 pressure ratio, single stage, low tip speed fan was tested with a serrated rotor leading edge to determine its effects on noise generation. The serrated rotor was produced by cutting teeth into the leading edge of the nominal rotor blades. The effects of speed and exhaust nozzle area on the scale models noise characteristics were investigated with both the nominal rotor and serrated rotor. Acoustic results indicate the serrations reduced front quadrant PNL's at takeoff power. In particular, the 200 foot (61.0 m) sideline noise was reduced from 3 to 4 PNdb at 40 deg for nominal and large nozzle operation. However, the rear quadrant maximum sideline PNL's were increased 1.5 to 3 PNdb at approach thust and up to 2 PNdb at takeoff thust with these serrated rotor blades. The configuration with the serrated rotor produced the lowest maximum 200 foot (61.0 m) sideline PNL for any given thust when the large nozzle (116% of design area) was employed.

Shear band formation in plastic bonded explosive (PBX)

NASA Astrophysics Data System (ADS)

Dey, T. N.; Johnson, J. N.

1998-07-01

Adiabatic shear bands can be a source of ignition and lead to detonation. At low to moderate deformation rates, 10-1000 s-1, two other mechanisms can also give rise to shear bands. These mechanisms are: 1) softening caused by micro-cracking and 2) a constitutive response with a non-associated flow rule as is observed in granular material such as soil. Brittle behavior at small strains and the granular nature of HMX suggest that PBX-9501 constitutive behavior may be similar to sand. A constitutive model for the first of these mechanisms is studied in a series of calculations. This viscoelastic constitutive model for PBX-9501 softens via a statistical crack model. A sand model is used to provide a non-associated flow rule and detailed results will be reported elsewhere. Both models generate shear band formation at 1-2% strain at nominal strain rates at and below 1000 s-1. Shear band formation is suppressed at higher strain rates. Both mechanisms may accelerate the formation of adiabatic shear bands.

Air Traffic Controllers' Control Strategies in the Terminal Area Under Off-Nominal Conditions

NASA Technical Reports Server (NTRS)

Martin, Lynne; Mercer, Joey; Callantine, Todd; Kupfer, Michael; Cabrall, Christopher

2012-01-01

A human-in-the-loop simulation investigated the robustness of a schedule-based terminal-area air traffic management concept, and its supporting controller tools, to off-nominal events - events that led to situations in which runway arrival schedules required adjustments and controllers could no longer use speed control alone to impose the necessary delays. The main research question was exploratory: to assess whether controllers could safely resolve and control the traffic during off-nominal events. A focus was the role of the supervisor - how he managed the schedules, how he assisted the controllers, what strategies he used, and which combinations of tools he used. Observations and questionnaire responses revealed supervisor strategies for resolving events followed a similar pattern: a standard approach specific to each type of event often resolved to a smooth conclusion. However, due to the range of factors influencing the event (e.g., environmental conditions, aircraft density on the schedule, etc.), sometimes the plan required revision and actions had a wide-ranging effect.

Aircraft Capability Management

NASA Technical Reports Server (NTRS)

Mumaw, Randy; Feary, Mike

2018-01-01

This presentation presents an overview of work performed at NASA Ames Research Center in 2017. The work concerns the analysis of current aircraft system management displays, and the initial development of an interface for providing information about aircraft system status. The new interface proposes a shift away from current aircraft system alerting interfaces that report the status of physical components, and towards displaying the implications of degradations on mission capability. The proposed interface describes these component failures in terms of operational consequences of aircraft system degradations. The research activity was an effort to examine the utility of different representations of complex systems and operating environments to support real-time decision making of off-nominal situations. A specific focus was to develop representations that provide better integrated information to allow pilots to more easily reason about the operational consequences of the off-nominal situations. The work is also seen as a pathway to autonomy, as information is integrated and understood in a form that automated responses could be developed for the off-nominal situations in the future.

Guidance and Control strategies for aerospace vehicles

NASA Technical Reports Server (NTRS)

Hibey, J. L.; Naidu, D. S.; Charalambous, C. D.

1989-01-01

A neighboring optimal guidance scheme was devised for a nonlinear dynamic system with stochastic inputs and perfect measurements as applicable to fuel optimal control of an aeroassisted orbital transfer vehicle. For the deterministic nonlinear dynamic system describing the atmospheric maneuver, a nominal trajectory was determined. Then, a neighboring, optimal guidance scheme was obtained for open loop and closed loop control configurations. Taking modelling uncertainties into account, a linear, stochastic, neighboring optimal guidance scheme was devised. Finally, the optimal trajectory was approximated as the sum of the deterministic nominal trajectory and the stochastic neighboring optimal solution. Numerical results are presented for a typical vehicle. A fuel-optimal control problem in aeroassisted noncoplanar orbital transfer is also addressed. The equations of motion for the atmospheric maneuver are nonlinear and the optimal (nominal) trajectory and control are obtained. In order to follow the nominal trajectory under actual conditions, a neighboring optimum guidance scheme is designed using linear quadratic regulator theory for onboard real-time implementation. One of the state variables is used as the independent variable in reference to the time. The weighting matrices in the performance index are chosen by a combination of a heuristic method and an optimal modal approach. The necessary feedback control law is obtained in order to minimize the deviations from the nominal conditions.

Mechanical Characterization of 3D Woven Carbon Composite

DTIC Science & Technology

2017-09-18

Woven Carbon/Glass Hybrid Spar Cap for Wind Turbine Rotor Blade,” Journal of Solar Engineering: Volume 128, November 2006, pp. 562-573. 2. In Tenax...A86AD439 Lead Wire Resistance (Ω, nominal) : 1 Significance : ASTM D7078 specifies that strength, strain and modulus be reported to three significant...0.05 Strain Gage Model / Batch No. : CEA-06-250UW-350 / A86AD438 Lead Wire Resistance (Ω, nominal) : 1 Significance : ASTM D7078 specifies that

Decomposing the Components of Friendship and Friends’ Influence on Adolescent Drinking and Smoking

PubMed Central

Fujimoto, Kayo; Valente, Thomas W

2012-01-01

Purpose Friendship networks are an important source of peer influence. However, existing network studies vary in terms of how they operationalize friendship and friend’s influence on adolescent substance use. This study uses social network analysis to characterize three types of friendship relations: (1) mutual or reciprocated, (2) directional, and (3) intimate friends. We then examine the relative effects of each friendship type on adolescent drinking and smoking behavior. Methods Using a saturated sample from the Add Health data, a nationally representative sample of high-school adolescents (N=2,533 nested in 12 schools), we computed the level of exposure to drinking and smoking of friends using a network exposure model, and their association with individual drinking and smoking using fixed effect models. Results Results indicated that the influence from (1) is stronger on adolescent substance use than (2), especially for smoking. Regarding the directionality of (2), adolescents are equally influenced by both nominating and nominated friends on their drinking and smoking behavior. Results for (3) indicated that the influence from “best friends” was weaker than the one from non-“best friends,” which indicates that the order of friend nomination may not matter as much as nomination reciprocation. Conclusions This study demonstrates that considering different features of friendship relationships is important in evaluating friends’ influence on adolescent substance use. Related policy implications are discussed. PMID:22824443

Low-Speed Flight Dynamic Tests and Analysis of the Orion Crew Module Drogue Parachute System

NASA Technical Reports Server (NTRS)

Hahne, David E.; Fremaux, C. Michael

2008-01-01

A test of a dynamically scaled model of the NASA Orion Crew Module (CM) with drogue parachutes was conducted in the NASA-Langley 20-Foot Vertical Spin Tunnel. The primary test objective was to assess the ability of the Orion Crew Module drogue parachute system to adequately stabilize the CM and reduce angular rates at low subsonic Mach numbers. Two attachment locations were tested: the current design nominal and an alternate. Experimental results indicated that the alternate attachment location showed a somewhat greater tendency to attenuate initial roll rate and reduce roll rate oscillations than the nominal location. Comparison of the experimental data to a Program To Optimize Simulated Trajectories (POST II) simulation of the experiment yielded results for the nominal attachment point that indicate differences between the low-speed pitch and yaw damping derivatives in the aerodynamic database and the physical model. Comparisons for the alternate attachment location indicate that riser twist plays a significant role in determining roll rate attenuation characteristics. Reevaluating the impact of the alternate attachment points using a simulation modified to account for these results showed significantly reduced roll rate attenuation tendencies when compared to the original simulation. Based on this modified simulation the alternate attachment point does not appear to offer a significant increase in allowable roll rate over the nominal configuration.

What Hispanic parents do to encourage and discourage 3-5 year old children to be active: a qualitative study using nominal group technique

PubMed Central

2013-01-01

Purpose Hispanic preschoolers are less active than their non-Hispanic peers. As part of a feasibility study to assess environmental and parenting influences on preschooler physical activity (PA) (Niños Activos), the aim of this study was to identify what parents do to encourage or discourage PA among Hispanic 3-5 year old children to inform the development of a new PA parenting practice instrument and future interventions to increase PA among Hispanic youth. Methods Nominal Group Technique (NGT), a structured multi-step group procedure, was used to elicit and prioritize responses from 10 groups of Hispanic parents regarding what parents do to encourage (5 groups) or discourage (5 groups) preschool aged children to be active. Five groups consisted of parents with low education (less than high school) and 5 with high education (high school or greater) distributed between the two NGT questions. Results Ten NGT groups (n = 74, range 4-11/group) generated 20-46 and 42-69 responses/group for practices that encourage or discourage PA respectively. Eight to 18 responses/group were elected as the most likely to encourage or discourage PA. Parental engagement in child activities, modeling PA, and feeding the child well were identified as parenting practices that encourage child PA. Allowing TV and videogame use, psychological control, physical or emotional abuse, and lack of parental engagement emerged as parenting practices that discourage children from being active. There were few differences in the pattern of responses by education level. Conclusions Parents identified ways they encourage and discourage 3-5 year-olds from PA, suggesting both are important targets for interventions. These will inform the development of a new PA parenting practice scale to be further evaluated. Further research should explore the role parents play in discouraging child PA, especially in using psychological control or submitting children to abuse, which were new findings in this study. PMID:23919301

What Hispanic parents do to encourage and discourage 3-5 year old children to be active: a qualitative study using nominal group technique.

PubMed

O'Connor, Teresia M; Cerin, Ester; Hughes, Sheryl O; Robles, Jessica; Thompson, Deborah; Baranowski, Tom; Lee, Rebecca E; Nicklas, Theresa; Shewchuk, Richard M

2013-08-06

Hispanic preschoolers are less active than their non-Hispanic peers. As part of a feasibility study to assess environmental and parenting influences on preschooler physical activity (PA) (Niños Activos), the aim of this study was to identify what parents do to encourage or discourage PA among Hispanic 3-5 year old children to inform the development of a new PA parenting practice instrument and future interventions to increase PA among Hispanic youth. Nominal Group Technique (NGT), a structured multi-step group procedure, was used to elicit and prioritize responses from 10 groups of Hispanic parents regarding what parents do to encourage (5 groups) or discourage (5 groups) preschool aged children to be active. Five groups consisted of parents with low education (less than high school) and 5 with high education (high school or greater) distributed between the two NGT questions. Ten NGT groups (n = 74, range 4-11/group) generated 20-46 and 42-69 responses/group for practices that encourage or discourage PA respectively. Eight to 18 responses/group were elected as the most likely to encourage or discourage PA. Parental engagement in child activities, modeling PA, and feeding the child well were identified as parenting practices that encourage child PA. Allowing TV and videogame use, psychological control, physical or emotional abuse, and lack of parental engagement emerged as parenting practices that discourage children from being active. There were few differences in the pattern of responses by education level. Parents identified ways they encourage and discourage 3-5 year-olds from PA, suggesting both are important targets for interventions. These will inform the development of a new PA parenting practice scale to be further evaluated. Further research should explore the role parents play in discouraging child PA, especially in using psychological control or submitting children to abuse, which were new findings in this study.

Hysteresis and uncertainty in soil water-retention curve parameters

USGS Publications Warehouse

Likos, William J.; Lu, Ning; Godt, Jonathan W.

2014-01-01

Accurate estimates of soil hydraulic parameters representing wetting and drying paths are required for predicting hydraulic and mechanical responses in a large number of applications. A comprehensive suite of laboratory experiments was conducted to measure hysteretic soil-water characteristic curves (SWCCs) representing a wide range of soil types. Results were used to quantitatively assess differences and uncertainty in three simplifications frequently adopted to estimate wetting-path SWCC parameters from more easily measured drying curves. They are the following: (1) αw=2αd, (2) nw=nd, and (3) θws=θds, where α, n, and θs are fitting parameters entering van Genuchten’s commonly adopted SWCC model, and the superscripts w and d indicate wetting and drying paths, respectively. The average ratio αw/αd for the data set was 2.24±1.25. Nominally cohesive soils had a lower αw/αd ratio (1.73±0.94) than nominally cohesionless soils (3.14±1.27). The average nw/nd ratio was 1.01±0.11 with no significant dependency on soil type, thus confirming the nw=nd simplification for a wider range of soil types than previously available. Water content at zero suction during wetting (θws) was consistently less than during drying (θds) owing to air entrapment. The θws/θds ratio averaged 0.85±0.10 and was comparable for nominally cohesive (0.87±0.11) and cohesionless (0.81±0.08) soils. Regression statistics are provided to quantitatively account for uncertainty in estimating hysteretic retention curves. Practical consequences are demonstrated for two case studies.

'Chain pooling' model selection as developed for the statistical analysis of a rotor burst protection experiment

NASA Technical Reports Server (NTRS)

Holms, A. G.

1977-01-01

A statistical decision procedure called chain pooling had been developed for model selection in fitting the results of a two-level fixed-effects full or fractional factorial experiment not having replication. The basic strategy included the use of one nominal level of significance for a preliminary test and a second nominal level of significance for the final test. The subject has been reexamined from the point of view of using as many as three successive statistical model deletion procedures in fitting the results of a single experiment. The investigation consisted of random number studies intended to simulate the results of a proposed aircraft turbine-engine rotor-burst-protection experiment. As a conservative approach, population model coefficients were chosen to represent a saturated 2 to the 4th power experiment with a distribution of parameter values unfavorable to the decision procedures. Three model selection strategies were developed.

Numerical analysis and experimental studies on solenoid common rail diesel injector with worn control valve

NASA Astrophysics Data System (ADS)

Krivtsov, S. N.; Yakimov, I. V.; Ozornin, S. P.

2018-03-01

A mathematical model of a solenoid common rail fuel injector was developed. Its difference from existing models is control valve wear simulation. A common rail injector of 0445110376 Series (Cummins ISf 2.8 Diesel engine) produced by Bosch Company was used as a research object. Injector parameters (fuel delivery and back leakage) were determined by calculation and experimental methods. GT-Suite model average R2 is 0.93 which means that it predicts the injection rate shape very accurately (nominal and marginal technical conditions of an injector). Numerical analysis and experimental studies showed that control valve wear increases back leakage and fuel delivery (especially at 160 MPa). The regression models for determining fuel delivery and back leakage effects on fuel pressure and energizing time were developed (for nominal and marginal technical conditions).

Impact of selected troposphere models on Precise Point Positioning convergence

NASA Astrophysics Data System (ADS)

Kalita, Jakub; Rzepecka, Zofia

2016-04-01

The Precise Point Positioning (PPP) absolute method is currently intensively investigated in order to reach fast convergence time. Among various sources that influence the convergence of the PPP, the tropospheric delay is one of the most important. Numerous models of tropospheric delay are developed and applied to PPP processing. However, with rare exceptions, the quality of those models does not allow fixing the zenith path delay tropospheric parameter, leaving difference between nominal and final value to the estimation process. Here we present comparison of several PPP result sets, each of which based on different troposphere model. The respective nominal values are adopted from models: VMF1, GPT2w, MOPS and ZERO-WET. The PPP solution admitted as reference is based on the final troposphere product from the International GNSS Service (IGS). The VMF1 mapping function was used for all processing variants in order to provide capability to compare impact of applied nominal values. The worst case initiates zenith wet delay with zero value (ZERO-WET). Impact from all possible models for tropospheric nominal values should fit inside both IGS and ZERO-WET border variants. The analysis is based on data from seven IGS stations located in mid-latitude European region from year 2014. For the purpose of this study several days with the most active troposphere were selected for each of the station. All the PPP solutions were determined using gLAB open-source software, with the Kalman filter implemented independently by the authors of this work. The processing was performed on 1 hour slices of observation data. In addition to the analysis of the output processing files, the presented study contains detailed analysis of the tropospheric conditions for the selected data. The overall results show that for the height component the VMF1 model outperforms GPT2w and MOPS by 35-40% and ZERO-WET variant by 150%. In most of the cases all solutions converge to the same values during first hour of processing. Finally, the results have been compared against results obtained during calm tropospheric conditions.

Analytic and heuristic processes in the detection and resolution of conflict.

PubMed

Ferreira, Mário B; Mata, André; Donkin, Christopher; Sherman, Steven J; Ihmels, Max

2016-10-01

Previous research with the ratio-bias task found larger response latencies for conflict trials where the heuristic- and analytic-based responses are assumed to be in opposition (e.g., choosing between 1/10 and 9/100 ratios of success) when compared to no-conflict trials where both processes converge on the same response (e.g., choosing between 1/10 and 11/100). This pattern is consistent with parallel dual-process models, which assume that there is effective, rather than lax, monitoring of the output of heuristic processing. It is, however, unclear why conflict resolution sometimes fails. Ratio-biased choices may increase because of a decline in analytical reasoning (leaving heuristic-based responses unopposed) or to a rise in heuristic processing (making it more difficult for analytic processes to override the heuristic preferences). Using the process-dissociation procedure, we found that instructions to respond logically and response speed affected analytic (controlled) processing (C), leaving heuristic processing (H) unchanged, whereas the intuitive preference for large nominators (as assessed by responses to equal ratio trials) affected H but not C. These findings create new challenges to the debate between dual-process and single-process accounts, which are discussed.

Decentralized Estimation and Vision-based Guidance of Fast Autonomous Systems with Guaranteed Performance in Uncertain Environments

DTIC Science & Technology

2013-04-22

Following for Unmanned Aerial Vehicles Using L1 Adaptive Augmentation of Commercial Autopilots, Journal of Guidance, Control, and Dynamics, (3 2010): 0...Naira Hovakimyan. L1 Adaptive Controller for MIMO system with Unmatched Uncertainties using Modi?ed Piecewise Constant Adaptation Law, IEEE 51st...adaptive input nominal input with  Nominal input L1 ‐based control generator  This L1 adaptive control architecture uses data from the reference model

An Adaptive Nonlinear Aircraft Maneuvering Envelope Estimation Approach for Online Applications

NASA Technical Reports Server (NTRS)

Schuet, Stefan R.; Lombaerts, Thomas Jan; Acosta, Diana; Wheeler, Kevin; Kaneshige, John

2014-01-01

A nonlinear aircraft model is presented and used to develop an overall unified robust and adaptive approach to passive trim and maneuverability envelope estimation with uncertainty quantification. The concept of time scale separation makes this method suitable for the online characterization of altered safe maneuvering limitations after impairment. The results can be used to provide pilot feedback and/or be combined with flight planning, trajectory generation, and guidance algorithms to help maintain safe aircraft operations in both nominal and off-nominal scenarios.

Passive control of discrete-frequency tones generated by coupled detuned cascades

NASA Astrophysics Data System (ADS)

Sawyer, S.; Fleeter, S.

2003-07-01

Discrete-frequency tones generated by rotor-stator interactions are of particular concern in the design of fans and compressors. Classical theory considers an isolated flat-plate cascade of identical uniformly spaced airfoils. The current analysis extends this tuned isolated cascade theory to consider coupled aerodynamically detuned cascades where aerodynamic detuning is accomplished by changing the chord of alternate rotor blades and stator vanes. In a coupled cascade analysis, the configuration of the rotor influences the downstream acoustic response of the stator, and the stator configuration influences the upstream acoustic response of the rotor. This coupled detuned cascade unsteady aerodynamic model is first applied to a baseline tuned stage. This baseline stage is then aerodynamically detuned by replacing alternate rotor blades and stator vanes with decreased chord airfoils. The nominal aerodynamically detuned stage configuration is then optimized, with the stage acoustic response decreased 13 dB upstream and 1 dB downstream at the design operating condition. A reduction in the acoustic response of the optimized aerodynamically detuned stage is then demonstrated over a range of operating conditions.

The nominal cooling tower

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burger, R.

1995-12-31

The heat Rejection Industry defines a nominal cooling tower as circulating three gallons of water per minute (GPM) per ton of refrigeration from entering the tower at 95{degrees}F. Hot Water temperature (HWT) Leaving at 85{degrees}F Cold Water Temperature (CWT) at a Design Wet Bulb of 70{degrees}F (WBT). Manufacturers then provide a selection chart based on various wet bulb temperatures and HWTs. The wet bulb fluctuates and varies through out the world since it is the combination ambient temperature, relative humidity, and/or dew point. Different HWT and CWT requirements are usually charted as they change, so that the user can selectmore » the nominal cooling tower model recommended by the manufacturer. Ask any HVAC operator, refinery manager, power generating station operator what happens when the Wet Bulb reaches or exceeds the design WBT of the area. He probably will tell you, {open_quotes}My cooling tower works quite well, but in the summer time, I usually have trouble with it.{close_quotes} This occurs because he is operating a nominal cooling tower.« less

Effects of noise and confidence thresholds in nominal and metric Axelrod dynamics of social influence

NASA Astrophysics Data System (ADS)

de Sanctis, Luca; Galla, Tobias

2009-04-01

We study the effects of bounded confidence thresholds and of interaction and external noise on Axelrod’s model of social influence. Our study is based on a combination of numerical simulations and an integration of the mean-field master equation describing the system in the thermodynamic limit. We find that interaction thresholds affect the system only quantitatively, but that they do not alter the basic phase structure. The known crossover between an ordered and a disordered state in finite systems subject to external noise persists in models with general confidence threshold. Interaction noise here facilitates the dynamics and reduces relaxation times. We also study Axelrod systems with metric features and point out similarities and differences compared to models with nominal features.

Waterhammer Modeling for the Ares I Upper Stage Reaction Control System Cold Flow Development Test Article

NASA Technical Reports Server (NTRS)

Williams, Jonathan H.

2010-01-01

The Upper Stage Reaction Control System provides three-axis attitude control for the Ares I launch vehicle during active Upper Stage flight. The system design must accommodate rapid thruster firing to maintain the proper launch trajectory and thus allow for the possibility to pulse multiple thrusters simultaneously. Rapid thruster valve closure creates an increase in static pressure, known as waterhammer, which propagates throughout the propellant system at pressures exceeding nominal design values. A series of development tests conducted in the fall of 2009 at Marshall Space Flight Center were performed using a water-flow test article to better understand fluid performance characteristics of the Upper Stage Reaction Control System. A subset of the tests examined waterhammer along with the subsequent pressure and frequency response in the flight-representative system and provided data to anchor numerical models. This thesis presents a comparison of waterhammer test results with numerical model and analytical results. An overview of the flight system, test article, modeling and analysis are also provided.

Waterhammer modeling for the Ares I Upper Stage Reaction Control System cold flow development test article

NASA Astrophysics Data System (ADS)

Williams, Jonathan Hunter

The Upper Stage Reaction Control System provides in-flight three-axis attitude control for the Ares I Upper Stage. The system design must accommodate rapid thruster firing to maintain proper launch trajectory and thus allow for the possibility to pulse multiple thrusters simultaneously. Rapid thruster valve closure creates an increase in static pressure, known as waterhammer, which propagates throughout the propellant system at pressures exceeding nominal design values. A series of development tests conducted at Marshall Space Flight Center in 2009 were performed using a water-flow test article to better understand fluid characteristics of the Upper Stage Reaction Control System. A subset of the tests examined the waterhammer pressure and frequency response in the flight-representative system and provided data to anchor numerical models. This thesis presents a comparison of waterhammer test results with numerical model and analytical results. An overview of the flight system, test article, modeling and analysis are also provided.

AGU Committees

NASA Astrophysics Data System (ADS)

Administrative Committees are responsible for those functions required for the overall performance or well-being of AGU as an organization. These committees are Audit and Legal Affairs, Budget and Finance*, Development, Nominations*, Planning, Statutes and Bylaws*, Tellers.Operating Committees are responsible for the policy direction and operational oversight of AGU's primary programs. The Operating Committees are Education and Human Resources, Fellows*, Information Technology, International Participation*, Meetings, Public Affairs, Public Information, Publications*.

Results of heat transfer tests of a 0.0175-scale space shuttle vehicle 5 model (60-OTS) in the NASA-Ames Research Center 3.5-foot hypersonic wind tunnel (test IH48)

NASA Technical Reports Server (NTRS)

Dye, W. H.; Lockman, W. K.

1976-01-01

Heat transfer data are presented for a .0175-scale model of the Rockwell International Space Shuttle Vehicle 5. The primary purpose of these tests was to obtain aerodynamic interference heating data on the external tank in the tank alone, second-, and first-stage configurations. Data were also obtained on the Orbiter and solid rocket boosters. Nominal Mach Nos. of 5.2 and 5.3 at nominal freestream unit Reynolds numbers of 1.5 and 5.0 million per foot, respectively, were investigated. Photographs of the tested configurations and test equipment are shown.

A Mesh Refinement Study on the Impact Response of a Shuttle Leading-Edge Panel Finite Element Simulation

NASA Technical Reports Server (NTRS)

Fasanella, Edwin L.; Jackson, Karen E.; Lyle, Karen H.; Spellman, Regina L.

2006-01-01

A study was performed to examine the influence of varying mesh density on an LS-DYNA simulation of a rectangular-shaped foam projectile impacting the space shuttle leading edge Panel 6. The shuttle leading-edge panels are fabricated of reinforced carbon-carbon (RCC) material. During the study, nine cases were executed with all possible combinations of coarse, baseline, and fine meshes of the foam and panel. For each simulation, the same material properties and impact conditions were specified and only the mesh density was varied. In the baseline model, the shell elements representing the RCC panel are approximately 0.2-in. on edge, whereas the foam elements are about 0.5-in. on edge. The element nominal edge-length for the baseline panel was halved to create a fine panel (0.1-in. edge length) mesh and doubled to create a coarse panel (0.4-in. edge length) mesh. In addition, the element nominal edge-length of the baseline foam projectile was halved (0.25-in. edge length) to create a fine foam mesh and doubled (1.0-in. edge length) to create a coarse foam mesh. The initial impact velocity of the foam was 775 ft/s. The simulations were executed in LS-DYNA for 6 ms of simulation time. Contour plots of resultant panel displacement and effective stress in the foam were compared at four discrete time intervals. Also, time-history responses of internal and kinetic energy of the panel, kinetic and hourglass energy of the foam, and resultant contact force were plotted to determine the influence of mesh density.

ITGB5 and AGFG1 variants are associated with severity of airway responsiveness.

PubMed

Himes, Blanca E; Qiu, Weiliang; Klanderman, Barbara; Ziniti, John; Senter-Sylvia, Jody; Szefler, Stanley J; Lemanske, Robert F; Zeiger, Robert S; Strunk, Robert C; Martinez, Fernando D; Boushey, Homer; Chinchilli, Vernon M; Israel, Elliot; Mauger, David; Koppelman, Gerard H; Nieuwenhuis, Maartje A E; Postma, Dirkje S; Vonk, Judith M; Rafaels, Nicholas; Hansel, Nadia N; Barnes, Kathleen; Raby, Benjamin; Tantisira, Kelan G; Weiss, Scott T

2013-08-28

Airway hyperresponsiveness (AHR), a primary characteristic of asthma, involves increased airway smooth muscle contractility in response to certain exposures. We sought to determine whether common genetic variants were associated with AHR severity. A genome-wide association study (GWAS) of AHR, quantified as the natural log of the dosage of methacholine causing a 20% drop in FEV1, was performed with 994 non-Hispanic white asthmatic subjects from three drug clinical trials: CAMP, CARE, and ACRN. Genotyping was performed on Affymetrix 6.0 arrays, and imputed data based on HapMap Phase 2, was used to measure the association of SNPs with AHR using a linear regression model. Replication of primary findings was attempted in 650 white subjects from DAG, and 3,354 white subjects from LHS. Evidence that the top SNPs were eQTL of their respective genes was sought using expression data available for 419 white CAMP subjects. The top primary GWAS associations were in rs848788 (P-value 7.2E-07) and rs6731443 (P-value 2.5E-06), located within the ITGB5 and AGFG1 genes, respectively. The AGFG1 result replicated at a nominally significant level in one independent population (LHS P-value 0.012), and the SNP had a nominally significant unadjusted P-value (0.0067) for being an eQTL of AGFG1. Based on current knowledge of ITGB5 and AGFG1, our results suggest that variants within these genes may be involved in modulating AHR. Future functional studies are required to confirm that our associations represent true biologically significant findings.

The relative effectiveness of computer-based and traditional resources for education in anatomy.

PubMed

Khot, Zaid; Quinlan, Kaitlyn; Norman, Geoffrey R; Wainman, Bruce

2013-01-01

There is increasing use of computer-based resources to teach anatomy, although no study has compared computer-based learning to traditional. In this study, we examine the effectiveness of three formats of anatomy learning: (1) a virtual reality (VR) computer-based module, (2) a static computer-based module providing Key Views (KV), (3) a plastic model. We conducted a controlled trial in which 60 undergraduate students had ten minutes to study the names of 20 different pelvic structures. The outcome measure was a 25 item short answer test consisting of 15 nominal and 10 functional questions, based on a cadaveric pelvis. All subjects also took a brief mental rotations test (MRT) as a measure of spatial ability, used as a covariate in the analysis. Data were analyzed with repeated measures ANOVA. The group learning from the model performed significantly better than the other two groups on the nominal questions (Model 67%; KV 40%; VR 41%, Effect size 1.19 and 1.29, respectively). There was no difference between the KV and VR groups. There was no difference between the groups on the functional questions (Model 28%; KV, 23%, VR 25%). Computer-based learning resources appear to have significant disadvantages compared to traditional specimens in learning nominal anatomy. Consistent with previous research, virtual reality shows no advantage over static presentation of key views. © 2013 American Association of Anatomists.

7 CFR 3431.3 - Definitions and acronyms.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AGRICULTURE VETERINARY MEDICINE LOAN REPAYMENT PROGRAM Designation of Veterinarian Shortage Situations § 3431... veterinarian, or equivalent, who will be responsible for nominating and certifying veterinarian shortage... process in subpart A of this part, determines has a shortage of veterinarians: (1) Geographical areas that...

7 CFR 3431.3 - Definitions and acronyms.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AGRICULTURE VETERINARY MEDICINE LOAN REPAYMENT PROGRAM Designation of Veterinarian Shortage Situations § 3431... veterinarian, or equivalent, who will be responsible for nominating and certifying veterinarian shortage... process in subpart A of this part, determines has a shortage of veterinarians: (1) Geographical areas that...

7 CFR 3431.3 - Definitions and acronyms.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AGRICULTURE VETERINARY MEDICINE LOAN REPAYMENT PROGRAM Designation of Veterinarian Shortage Situations § 3431... veterinarian, or equivalent, who will be responsible for nominating and certifying veterinarian shortage... process in subpart A of this part, determines has a shortage of veterinarians: (1) Geographical areas that...

77 FR 23494 - Invasive Species Advisory Committee; Request for Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-19

...; marine fisheries; forest health and management; potable and irrigation water management; natural resource.../mn_NISC_ManagementPlan.html . NISC is responsible for effective implementation of the Plan including... suburban park management; energy and mineral resource development; corporate land management; native plant...

The role of twinning deformation on the hardening response of polycrystalline magnesium from discrete dislocation dynamics simulations

DOE PAGES

Fan, Haidong; Aubry, Sylvie; Arsenlis, Athanasios; ...

2015-04-13

The mechanical response of micro-twinned polycrystalline magnesium was studied through three-dimensional discrete dislocation dynamics (DDD). A systematic interaction model between dislocations and (1012) tension twin boundaries (TBs) was proposed and introduced into the DDD framework. In addition, a nominal grain boundary (GB) model agreeing with experimental results was also introduced to mimic the GB’s barrier effect. The current simulation results show that TBs act as a strong obstacle to gliding dislocations, which contributes significantly to the hardening behavior of magnesium. On the other hand, the deformation accommodated by twinning plays a softening role. Therefore, the concave shape of the Mgmore » stress-strain curve results from the competition between dislocation-TB induced hardening and twinning deformation induced softening. At low strain levels, twinning deformation induced softening dominates and a decreasing hardening rate is observed in Stage-I. In Stage-II, both the hardening and softening effects decline, but twinning deformation induced softening declines faster, which leads to an increasing hardening rate.« less

Nonlinear dynamic analysis of rigid rotor supported by gas foil bearings: Effects of gas film and foil structure on subsynchronous vibrations

NASA Astrophysics Data System (ADS)

Guo, Zhiyang; Feng, Kai; Liu, Tianyu; Lyu, Peng; Zhang, Tao

2018-07-01

Highly nonlinear subsynchronous vibrations are the main causing factors of failure in gas foil bearing (GFB)-rotor systems. Thus, investigating the vibration generation mechanisms and the relationship between subsynchronous vibrations and GFBs is necessary to ensure the healthy operation of rotor systems. In this study, an integrated nonlinear dynamic model with the consideration of shaft motion, unsteady gas film, and deformations of foil structure is established to investigate the effect of gas film and foil structure on system subsynchronous response. One test rig of GFB-rotor system is developed for model comparison. High agreement is shown between the prediction and test data, especially in the frequency domain. The nonlinear dynamic response is analyzed using waterfall plots, operation deflection shapes, journal orbits, Poincaré maps, and fast Fourier transforms. The parameter studies reveal that subsynchronous vibrations are highly related to gas film and foil structure. Subsynchronous vibrations can be adjusted by parameters such as bump stiffness, nominal clearance, and static loads. Therefore, gas foil bearing parameters should be carefully adjusted by system manufacturers to achieve the best rotordynamic performance.

The evaluation of the OSGLR algorithm for restructurable controls

NASA Technical Reports Server (NTRS)

Bonnice, W. F.; Wagner, E.; Hall, S. R.; Motyka, P.

1986-01-01

The detection and isolation of commercial aircraft control surface and actuator failures using the orthogonal series generalized likelihood ratio (OSGLR) test was evaluated. The OSGLR algorithm was chosen as the most promising algorithm based on a preliminary evaluation of three failure detection and isolation (FDI) algorithms (the detection filter, the generalized likelihood ratio test, and the OSGLR test) and a survey of the literature. One difficulty of analytic FDI techniques and the OSGLR algorithm in particular is their sensitivity to modeling errors. Therefore, methods of improving the robustness of the algorithm were examined with the incorporation of age-weighting into the algorithm being the most effective approach, significantly reducing the sensitivity of the algorithm to modeling errors. The steady-state implementation of the algorithm based on a single cruise linear model was evaluated using a nonlinear simulation of a C-130 aircraft. A number of off-nominal no-failure flight conditions including maneuvers, nonzero flap deflections, different turbulence levels and steady winds were tested. Based on the no-failure decision functions produced by off-nominal flight conditions, the failure detection performance at the nominal flight condition was determined. The extension of the algorithm to a wider flight envelope by scheduling the linear models used by the algorithm on dynamic pressure and flap deflection was also considered. Since simply scheduling the linear models over the entire flight envelope is unlikely to be adequate, scheduling of the steady-state implentation of the algorithm was briefly investigated.

Parametric excitation of tire-wheel assemblies by a stiffness non-uniformity

NASA Astrophysics Data System (ADS)

Stutts, D. S.; Krousgrill, C. M.; Soedel, W.

1995-01-01

A simple model of the effect of a concentrated radial stiffness non-uniformity in a passenger car tire is presented. The model treats the tread band of the tire as a rigid ring supported on a viscoelastic foundation. The distributed radial stiffness is lumped into equivalent horizontal (fore-and-aft) and vertical stiffnesses. The concentrated radial stiffness non-uniformity is modeled by treating the tread band as fixed, and the stiffness non-uniformity as rotating around it at the nominal angular velocity of the wheel. Due to loading, the center of mass of the tread band ring model is displaced upward with respect to the wheel spindle and, therefore, the rotating stiffness non-uniformity is alternately compressed and stretched through one complete rotation. This stretching and compressing of the stiffness non-uniformity results in force transmission to the wheel spindle at twice the nominal angular velocity in frequency, and therefore, would excite a given resonance at one-half the nominal angular wheel velocity that a mass unbalance would. The forcing produced by the stiffness non-uniformity is parametric in nature, thus creating the possibility of parametric resonance. The basic theory of the parametric resonance is explained, and a parameter study using derived lumped parameters based on a typical passenger car tire is performed. This study revealed that parametric resonance in passenger car tires, although possible, is unlikely at normal highway speeds as predicted by this model unless the tire is partially deflated.

Closed-Loop Simulation Study of the Ares I Upper Stage Thrust Vector Control Subsystem for Nominal and Failure Scenarios

NASA Technical Reports Server (NTRS)

Chicatelli, Amy; Fulton, Chris; Connolly, Joe; Hunker, Keith

2010-01-01

As a replacement to the current Shuttle, the Ares I rocket and Orion crew module are currently under development by the National Aeronautics and Space Administration (NASA). This new launch vehicle is segmented into major elements, one of which is the Upper Stage (US). The US is further broken down into subsystems, one of which is the Thrust Vector Control (TVC) subsystem which gimbals the US rocket nozzle. Nominal and off-nominal simulations for the US TVC subsystem are needed in order to support the development of software used for control systems and diagnostics. In addition, a clear and complete understanding of the effect of off-nominal conditions on the vehicle flight dynamics is desired. To achieve these goals, a simulation of the US TVC subsystem combined with the Ares I vehicle as developed. This closed-loop dynamic model was created using Matlab s Simulink and a modified version of a vehicle simulation, MAVERIC, which is currently used in the Ares I project and was developed by the Marshall Space Flight Center (MSFC). For this report, the effects on the flight trajectory of the Ares I vehicle are investigated after failures are injected into the US TVC subsystem. The comparisons of the off-nominal conditions observed in the US TVC subsystem with those of the Ares I vehicle flight dynamics are of particular interest.

Design and validation of a GNC system for missions to asteroids: the AIM scenario

NASA Astrophysics Data System (ADS)

Pellacani, A.; Kicman, P.; Suatoni, M.; Casasco, M.; Gil, J.; Carnelli, I.

2017-12-01

Deep space missions, and in particular missions to asteroids, impose a certain level of autonomy that depends on the mission objectives. If the mission requires the spacecraft to perform close approaches to the target body (the extreme case being a landing scenario), the autonomy level must be increased to guarantee the fast and reactive response which is required in both nominal and contingency operations. The GNC system must be designed in accordance with the required level of autonomy. The GNC system designed and tested in the frame of ESA's Asteroid Impact Mission (AIM) system studies (Phase A/B1 and Consolidation Phase) is an example of an autonomous GNC system that meets the challenging objectives of AIM. The paper reports the design of such GNC system and its validation through a DDVV plan that includes Model-in-the-Loop and Hardware-in-the-Loop testing. Main focus is the translational navigation, which is able to provide online the relative state estimation with respect to the target body using exclusively cameras as relative navigation sensors. The relative navigation outputs are meant to be used for nominal spacecraft trajectory corrections as well as to estimate the collision risk with the asteroid and, if needed, to command the execution of a collision avoidance manoeuvre to guarantee spacecraft safety

An evaluative model of system performance in manned teleoperational systems

NASA Technical Reports Server (NTRS)

Haines, Richard F.

1989-01-01

Manned teleoperational systems are used in aerospace operations in which humans must interact with machines remotely. Manual guidance of remotely piloted vehicles, controling a wind tunnel, carrying out a scientific procedure remotely are examples of teleoperations. A four input parameter throughput (Tp) model is presented which can be used to evaluate complex, manned, teleoperations-based systems and make critical comparisons among candidate control systems. The first two parameters of this model deal with nominal (A) and off-nominal (B) predicted events while the last two focus on measured events of two types, human performance (C) and system performance (D). Digital simulations showed that the expression A(1-B)/C+D) produced the greatest homogeneity of variance and distribution symmetry. Results from a recently completed manned life science telescience experiment will be used to further validate the model. Complex, interacting teleoperational systems may be systematically evaluated using this expression much like a computer benchmark is used.

Barriers to Medication Decision Making in Women with Lupus Nephritis: A Formative Study using Nominal Group Technique.

PubMed

Singh, Jasvinder A; Qu, Haiyan; Yazdany, Jinoos; Chatham, Winn; Dall'era, Maria; Shewchuk, Richard M

2015-09-01

To assess the perspectives of women with lupus nephritis on barriers to medication decision making. We used the nominal group technique (NGT), a structured process to elicit ideas from participants, for a formative assessment. Eight NGT meetings were conducted in English and moderated by an expert NGT researcher at 2 medical centers. Participants responded to the question: "What sorts of things make it hard for people to decide to take the medicines that doctors prescribe for treating their lupus kidney disease?" Patients nominated, discussed, and prioritized barriers to decisional processes involving medications for treating lupus nephritis. Fifty-one women with lupus nephritis with a mean age of 40.6 ± 13.3 years and disease duration of 11.8 ± 8.3 years participated in 8 NGT meetings: 26 African Americans (4 panels), 13 Hispanics (2 panels), and 12 whites (2 panels). Of the participants, 36.5% had obtained at least a college degree and 55.8% needed some help in reading health materials. Of the 248 responses generated (range 19-37 responses/panel), 100 responses (40%) were perceived by patients as having relatively greater importance than other barriers in their own decision-making processes. The most salient perceived barriers, as indicated by percent-weighted votes assigned, were known/anticipated side effects (15.6%), medication expense/ability to afford medications (8.2%), and the fear that the medication could cause other diseases (7.8%). Women with lupus nephritis identified specific barriers to decisions related to medications. Information relevant to known/anticipated medication side effects and medication cost will form the basis of a patient guide for women with systemic lupus erythematosus, currently under development.

Children's comprehension skill and the understanding of nominal metaphors.

PubMed

Seigneuric, Alix; Megherbi, Hakima; Bueno, Steve; Lebahar, Julie; Bianco, Maryse

2016-10-01

According to Levorato and Cacciari's global elaboration model, understanding figurative language is explained by the same processes and background knowledge that are required for literal language. In this study, we investigated the relation between children's comprehension skill and the ability to understand referential nominal metaphors. Two groups of poor versus good comprehenders (8- to 10-year-olds) matched for word reading and vocabulary skills were invited to identify the referent of nouns used metaphorically or literally in short texts. Compared with good comprehenders, performance of poor comprehenders showed a substantial decrease in the metaphoric condition. Moreover, their performance was strongly affected by the degree of semantic incongruence between the terms of the nominal metaphor. These findings are discussed in relation to several factors, in particular the ability to use contextual information and semantic processing. Copyright © 2016 Elsevier Inc. All rights reserved.

Likelihoods for fixed rank nomination networks

PubMed Central

HOFF, PETER; FOSDICK, BAILEY; VOLFOVSKY, ALEX; STOVEL, KATHERINE

2014-01-01

Many studies that gather social network data use survey methods that lead to censored, missing, or otherwise incomplete information. For example, the popular fixed rank nomination (FRN) scheme, often used in studies of schools and businesses, asks study participants to nominate and rank at most a small number of contacts or friends, leaving the existence of other relations uncertain. However, most statistical models are formulated in terms of completely observed binary networks. Statistical analyses of FRN data with such models ignore the censored and ranked nature of the data and could potentially result in misleading statistical inference. To investigate this possibility, we compare Bayesian parameter estimates obtained from a likelihood for complete binary networks with those obtained from likelihoods that are derived from the FRN scheme, and therefore accommodate the ranked and censored nature of the data. We show analytically and via simulation that the binary likelihood can provide misleading inference, particularly for certain model parameters that relate network ties to characteristics of individuals and pairs of individuals. We also compare these different likelihoods in a data analysis of several adolescent social networks. For some of these networks, the parameter estimates from the binary and FRN likelihoods lead to different conclusions, indicating the importance of analyzing FRN data with a method that accounts for the FRN survey design. PMID:25110586

Aerodynamic Improvements to Cargo Carrying Rail Cars due to Roof Modifications

NASA Astrophysics Data System (ADS)

Condie, Robert; Maynes, Daniel

2012-11-01

The aerodynamic drag associated with the transport of commodities by rail is becoming increasingly important as the cost of diesel fuel increases. We provide an assessment of the influence of the roof structure on aerodynamic performance of two dissimilar rail cars, namely automobile carrying cars and coal carrying cars. Currently, the roof material for automobile carrying rail cars is corrugated steel, with the corrugation aligned perpendicular to the direction of travel. Coal cars are currently left uncovered for loading convenience and on the return leg from the power plant are empty. Aerodynamic drag data have been obtained through wind tunnel testing on 1/29 scale models to understand the savings that may be realized by judicious modification to the tops of both these car types. For the automobile-carrying cars, testing is performed for the corrugated and smooth roof configurations. This modification alone has the potential of reducing the car drag coefficient by nominally 25%. A broader study is performed for the coal cars, with data being acquired for coal filled models, empty models, and several cover prototype configurations. The results reveal that implementation of a cover may yield reductions in the aerodynamic drag for both coal filled (nominally 7%) and empty coal cars (nominally 30%).

A New Aerodynamic Data Dispersion Method for Launch Vehicle Design

NASA Technical Reports Server (NTRS)

Pinier, Jeremy T.

2011-01-01

A novel method for implementing aerodynamic data dispersion analysis is herein introduced. A general mathematical approach combined with physical modeling tailored to the aerodynamic quantity of interest enables the generation of more realistically relevant dispersed data and, in turn, more reasonable flight simulation results. The method simultaneously allows for the aerodynamic quantities and their derivatives to be dispersed given a set of non-arbitrary constraints, which stresses the controls model in more ways than with the traditional bias up or down of the nominal data within the uncertainty bounds. The adoption and implementation of this new method within the NASA Ares I Crew Launch Vehicle Project has resulted in significant increases in predicted roll control authority, and lowered the induced risks for flight test operations. One direct impact on launch vehicles is a reduced size for auxiliary control systems, and the possibility of an increased payload. This technique has the potential of being applied to problems in multiple areas where nominal data together with uncertainties are used to produce simulations using Monte Carlo type random sampling methods. It is recommended that a tailored physics-based dispersion model be delivered with any aerodynamic product that includes nominal data and uncertainties, in order to make flight simulations more realistic and allow for leaner spacecraft designs.

Longitudinal analysis of large social networks: Estimating the effect of health traits on changes in friendship ties

PubMed Central

O'Malley, A James; Christakis, Nicholas A

2011-01-01

We develop novel mixed effects models to examine the role of health traits on the status of peoples' close friendship nominations in the Framingham Heart Study. The health traits considered are both mutable (body mass index (BMI), smoking, blood pressure, body proportion, muscularity, and depression) and, for comparison, basically immutable (height, birth order, personality type, only child, and handedness); and the traits have varying degrees of observability. We test the hypotheses that existing ties (i.e. close friendship nominations) are more likely to dissolve between people with dissimilar (mutable and observable) health traits whereas new ties are more likely to form between those with similar (mutable and observable) traits while controlling for persons' age, gender, geographic separation, and education. The mixed effects models contain random effects for both the nominator (ego) and nominated (alter) persons in a tie to account for the fact that people were involved in multiple relationships and contributed observations at multiple exams. Results for BMI support the hypotheses that people of similar BMI are less likely to dissolve existing ties and more likely to form ties, while smoker to non-smoker ties were the least likely to dissolve and smoker to smoker ties were the most likely to form. We also validated previously known findings regarding homophily on age and gender, and found evidence that homophily also depends upon geographic separation. Copyright © 2011 John Wiley & Sons, Ltd. PMID:21287589

Decomposing the components of friendship and friends' influence on adolescent drinking and smoking.

PubMed

Fujimoto, Kayo; Valente, Thomas W

2012-08-01

Friendship networks are an important source of peer influence. However, existing network studies vary in terms of how they operationalize friendship and friend's influence on adolescent substance use. This study uses social network analysis to characterize three types of friendship relations: (1) mutual or reciprocated, (2) directional, and (3) intimate friends. We then examine the relative effects of each friendship type on adolescent drinking and smoking behavior. Using a saturated sample from the Add Health data, a nationally representative sample of high school adolescents (N = 2,533 nested in 12 schools), we computed the level of exposure to drinking and smoking of friends using a network exposure model, and their association with individual drinking and smoking using fixed effect models. Results indicated that the influence from mutual or reciprocated type of friendship relations is stronger on adolescent substance use than directional, especially for smoking. Regarding the directionality of directional type of friendship relations, adolescents are equally influenced by both nominating and nominated friends on their drinking and smoking behavior. Results for intimate friends friendship relations indicated that the influence from "best friends" was weaker than the one from non-"best friends," which indicates that the order of friend nomination may not matter as much as nomination reciprocation. This study demonstrates that considering different features of friendship relationships is important in evaluating friends' influence on adolescent substance use. Related policy implications are discussed. Copyright © 2012 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Longitudinal analysis of large social networks: estimating the effect of health traits on changes in friendship ties.

PubMed

O'Malley, A James; Christakis, Nicholas A

2011-04-30

We develop novel mixed effects models to examine the role of health traits on the status of peoples' close friendship nominations in the Framingham Heart Study. The health traits considered are both mutable (body mass index (BMI), smoking, blood pressure, body proportion, muscularity, and depression) and, for comparison, basically immutable (height, birth order, personality type, only child, and handedness); and the traits have varying degrees of observability. We test the hypotheses that existing ties (i.e. close friendship nominations) are more likely to dissolve between people with dissimilar (mutable and observable) health traits whereas new ties are more likely to form between those with similar (mutable and observable) traits while controlling for persons' age, gender, geographic separation, and education. The mixed effects models contain random effects for both the nominator (ego) and nominated (alter) persons in a tie to account for the fact that people were involved in multiple relationships and contributed observations at multiple exams. Results for BMI support the hypotheses that people of similar BMI are less likely to dissolve existing ties and more likely to form ties, while smoker to non-smoker ties were the least likely to dissolve and smoker to smoker ties were the most likely to form. We also validated previously known findings regarding homophily on age and gender, and found evidence that homophily also depends upon geographic separation. Copyright © 2011 John Wiley & Sons, Ltd.

Developing an Abaqus *HYPERFOAM Model for M9747 (4003047) Cellular Silicone Foam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siranosian, Antranik A.; Stevens, R. Robert

This report documents work done to develop an Abaqus *HYPERFOAM hyperelastic model for M9747 (4003047) cellular silicone foam for use in quasi-static analyses at ambient temperature. Experimental data, from acceptance tests for 'Pad A' conducted at the Kansas City Plant (KCP), was used to calibrate the model. The data includes gap (relative displacement) and load measurements from three locations on the pad. Thirteen sets of data, from pads with different serial numbers, were provided. The thirty-nine gap-load curves were extracted from the thirteen supplied Excel spreadsheets and analyzed, and from those thirty-nine one set of data, representing a qualitative mean,more » was chosen to calibrate the model. The data was converted from gap and load to nominal (engineering) strain and nominal stress in order to implement it in Abaqus. Strain computations required initial pad thickness estimates. An Abaqus model of a right-circular cylinder was used to evaluate and calibrate the *HYPERFOAM model.« less

Validity of DSM-IV attention–deficit/hyperactivity disorder symptom dimensions and subtypes

PubMed Central

Willcutt, Erik G.; Nigg, Joel T.; Pennington, Bruce F.; Solanto, Mary V.; Rohde, Luis A.; Tannock, Rosemary; Loo, Sandra K.; Carlson, Caryn L.; McBurnett, Keith; Lahey, Benjamin B.

2013-01-01

DSM-IV criteria for ADHD specify two dimensions of inattention and hyperactivity-impulsivity symptoms that are used to define three nominal subtypes: predominantly hyperactive-impulsive type (ADHD-H), predominantly inattentive type (ADHD-I), and combined type (ADHD-C). To aid decision-making for DSM-5 and other future diagnostic systems, a comprehensive literature review and meta-analysis of 546 studies was completed to evaluate the validity of the DSM-IV model of ADHD. Results indicated that DSM-IV criteria identify individuals with significant and persistent impairment in social, academic, occupational, and adaptive functioning when intelligence, demographic factors, and concurrent psychopathology are controlled. Available data overwhelmingly support the concurrent, predictive, and discriminant validity of the distinction between inattention and hyperactivity-impulsivity symptoms, and indicate that nearly all differences among the nominal subtypes are consistent with the relative levels of inattention and hyperactivity-impulsivity symptoms that define the subtypes. In contrast, the validity of the DSM-IV subtype model is compromised by weak evidence for the validity of ADHD-H after first grade, minimal support for the distinction between ADHD-I and ADHD-C in studies of etiological influences, academic and cognitive functioning, and treatment response, and the marked longitudinal instability of all three subtypes. Overall, it is concluded that the DSM-IV ADHD subtypes provide a convenient clinical shorthand to describe the functional and behavioral correlates of current levels of inattention and hyperactivity-impulsivity symptoms, but do not identify discrete subgroups with sufficient long-term stability to justify the classification of distinct forms of the disorder. Empirical support is stronger for an alternative model that would replace the subtypes with dimensional modifiers that reflect the number of inattention and hyperactivity-impulsivity symptoms at the time of assessment. PMID:22612200

Shear Band Formation in Plastic-Bonded Explosives (PBX)

NASA Astrophysics Data System (ADS)

Dey, Thomas N.; Johnson, James N.

1997-07-01

Adiabatic shear bands can be a source of ignition and lead to detonation. At low to moderate deformation rates, 10--1000 s-1, two other mechanisms can also give rise to shear bands. These mechanisms are: softening caused by micro-cracking and (2) a constitutive response with a non-associated flow rule as is observed in granular material such as soil. Brittle behavior at small strains and the granular nature of HMX suggest that PBX-9501 constitutive behavior may be similar to sand. A constitutive model for each of these mechanims is studied in a series of calculations. A viscoelastic constitutive model for PBX-9501 softens via a statistical crack model, based on the work of Dienes (1986). A sand model is used to provide a non-associated flow rule. Both models generate shear band formation at 1--2% strain at nominal strain rates at and below 1000 s-1. Shear band formation is suppressed at higher strain rates. The sand model gives qualitative agreement for location and orientation of shear bands observed in a punch experiment. Both mechanisms may accelerate the formation of adiabatic shear bands.

Adjusting for Confounding in Early Postlaunch Settings: Going Beyond Logistic Regression Models.

PubMed

Schmidt, Amand F; Klungel, Olaf H; Groenwold, Rolf H H

2016-01-01

Postlaunch data on medical treatments can be analyzed to explore adverse events or relative effectiveness in real-life settings. These analyses are often complicated by the number of potential confounders and the possibility of model misspecification. We conducted a simulation study to compare the performance of logistic regression, propensity score, disease risk score, and stabilized inverse probability weighting methods to adjust for confounding. Model misspecification was induced in the independent derivation dataset. We evaluated performance using relative bias confidence interval coverage of the true effect, among other metrics. At low events per coefficient (1.0 and 0.5), the logistic regression estimates had a large relative bias (greater than -100%). Bias of the disease risk score estimates was at most 13.48% and 18.83%. For the propensity score model, this was 8.74% and >100%, respectively. At events per coefficient of 1.0 and 0.5, inverse probability weighting frequently failed or reduced to a crude regression, resulting in biases of -8.49% and 24.55%. Coverage of logistic regression estimates became less than the nominal level at events per coefficient ≤5. For the disease risk score, inverse probability weighting, and propensity score, coverage became less than nominal at events per coefficient ≤2.5, ≤1.0, and ≤1.0, respectively. Bias of misspecified disease risk score models was 16.55%. In settings with low events/exposed subjects per coefficient, disease risk score methods can be useful alternatives to logistic regression models, especially when propensity score models cannot be used. Despite better performance of disease risk score methods than logistic regression and propensity score models in small events per coefficient settings, bias, and coverage still deviated from nominal.

Multiscale Static Analysis of Notched and Unnotched Laminates Using the Generalized Method of Cells

NASA Technical Reports Server (NTRS)

Naghipour Ghezeljeh, Paria; Arnold, Steven M.; Pineda, Evan J.; Stier, Bertram; Hansen, Lucas; Bednarcyk, Brett A.; Waas, Anthony M.

2016-01-01

The generalized method of cells (GMC) is demonstrated to be a viable micromechanics tool for predicting the deformation and failure response of laminated composites, with and without notches, subjected to tensile and compressive static loading. Given the axial [0], transverse [90], and shear [+45/-45] response of a carbon/epoxy (IM7/977-3) system, the unnotched and notched behavior of three multidirectional layups (Layup 1: [0,45,90,-45](sub 2S), Layup 2: [0,60,0](sub 3S), and Layup 3: [30,60,90,-30, -60](sub 2S)) are predicted under both tensile and compressive static loading. Matrix nonlinearity is modeled in two ways. The first assumes all nonlinearity is due to anisotropic progressive damage of the matrix only, which is modeled, using the multiaxial mixed-mode continuum damage model (MMCDM) within GMC. The second utilizes matrix plasticity coupled with brittle final failure based on the maximum principle strain criteria to account for matrix nonlinearity and failure within the Finite Element Analysis--Micromechanics Analysis Code (FEAMAC) software multiscale framework. Both MMCDM and plasticity models incorporate brittle strain- and stress-based failure criteria for the fiber. Upon satisfaction of these criteria, the fiber properties are immediately reduced to a nominal value. The constitutive response for each constituent (fiber and matrix) is characterized using a combination of vendor data and the axial, transverse, and shear responses of unnotched laminates. Then, the capability of the multiscale methodology is assessed by performing blind predictions of the mentioned notched and unnotched composite laminates response under tensile and compressive loading. Tabulated data along with the detailed results (i.e., stress-strain curves as well as damage evolution states at various ratios of strain to failure) for all laminates are presented.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gevorgian, Vahan; Zhang, Yingchen

The electrical frequency of an interconnected power system must be maintained close its nominal level at all times. Excessive under- and overfrequency excursions can lead to load shedding, instability, machine damage, and even blackouts. There is a rising concern in the electric power industry in recent years about the declining amount of inertia and primary frequency response (PFR) in many interconnections. This decline may continue due to increasing penetrations of inverter-coupled generation and the planned retirements of conventional thermal plants. Inverter-coupled variable wind generation is capable of contributing to PFR and inertia with a response that is different from thatmore » of conventional generation. It is not yet entirely understood how such a response will affect the system at different wind power penetration levels. The modeling work presented in this paper evaluates the impact of wind generation's provision of these active power control strategies on a large, synchronous interconnection. All simulations were conducted on the U.S. Western Interconnection with different levels of instantaneous wind power penetrations (up to 80%). The ability of wind power plants to provide PFR - and a combination of synthetic inertial response and PFR - significantly improved the frequency response performance of the system.« less

RESPONSES OF LUNG CELLS TO METALS IN MANUFACTURED NANOPARTICLES

EPA Science Inventory

ACHP | Tribal Historic Preservation Officers

Science.gov Websites

tribes to take on more formal responsibility for the preservation of significant historic properties on preservation of significant historic properties. Those functions include identifying and maintaining inventories of culturally significant properties, nominating properties to national and tribal registers of

75 FR 39011 - Agency Information Collection Activities; Proposed Collection; Comment Request; Nomination...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-07

...) to the Office of Management and Budget (OMB). Before submitting the ICR to OMB for review and... outstanding individuals, teams, companies, organizations, and government institutions in 54 countries. Awards...: Originality and public purpose; leadership and corporate responsibility; global perspective and implication...

Electrical and optical performance of midwave infrared InAsSb heterostructure detectors

NASA Astrophysics Data System (ADS)

Gomółka, Emilia; Kopytko, Małgorzata; Markowska, Olga; Michalczewski, Krystian; Kubiszyn, Łukasz; Kębłowski, Artur; Jureńczyk, Jarosław; Gawron, Waldemar; Martyniuk, Piotr Marcin; Piotrowski, Józef; Rutkowski, Jarosław; Rogalski, Antoni

2018-02-01

We investigate the high-operating temperature performance of InAsSb/AlSb heterostructure detectors with cutoff wavelengths near 5 μm at 230 K. The devices have been fabricated with different types of absorbing layers: nominally undoped absorber (with n-type conductivity), and both n- and p-type doped. The results show that the device performance strongly depends on absorber layer type. Generally, the p-type absorber provides higher values of current responsivity than the n-type absorber, but at the same time also higher values of dark current. The device with the nominally undoped absorbing layer shows moderate values of both current responsivity and dark current. Resulting detectivities D * of nonimmersed devices vary from 2 × 109 to 5 × 109 cm Hz1/2 W ? 1 at 230 K, which is easily achievable with a two-stage thermoelectric cooler. Optical immersion increases the detectivity up to 5 × 1010 cm Hz1/2 W ? 1.

Performance and robustness of hybrid model predictive control for controllable dampers in building models

NASA Astrophysics Data System (ADS)

Johnson, Erik A.; Elhaddad, Wael M.; Wojtkiewicz, Steven F.

2016-04-01

A variety of strategies have been developed over the past few decades to determine controllable damping device forces to mitigate the response of structures and mechanical systems to natural hazards and other excitations. These "smart" damping devices produce forces through passive means but have properties that can be controlled in real time, based on sensor measurements of response across the structure, to dramatically reduce structural motion by exploiting more than the local "information" that is available to purely passive devices. A common strategy is to design optimal damping forces using active control approaches and then try to reproduce those forces with the smart damper. However, these design forces, for some structures and performance objectives, may achieve high performance by selectively adding energy, which cannot be replicated by a controllable damping device, causing the smart damper performance to fall far short of what an active system would provide. The authors have recently demonstrated that a model predictive control strategy using hybrid system models, which utilize both continuous and binary states (the latter to capture the switching behavior between dissipative and non-dissipative forces), can provide reductions in structural response on the order of 50% relative to the conventional clipped-optimal design strategy. This paper explores the robustness of this newly proposed control strategy through evaluating controllable damper performance when the structure model differs from the nominal one used to design the damping strategy. Results from the application to a two-degree-of-freedom structure model confirms the robustness of the proposed strategy.

Calcium channel dynamics limit synaptic release in response to prosthetic stimulation with sinusoidal waveforms

PubMed Central

Freeman, Daniel K.; Jeng, Jed S.; Kelly, Shawn K.; Hartveit, Espen; Fried, Shelley I.

2011-01-01

Extracellular electric stimulation with sinusoidal waveforms has been shown to allow preferential activation of individual types of retinal neurons by varying stimulus frequency. It is important to understand the mechanisms underlying this frequency dependence as a step towards improving methods of preferential activation. In order to elucidate these mechanisms, we implemented a morphologically realistic model of a retinal bipolar cell and measured the response to extracellular stimulation with sinusoidal waveforms. We compared the frequency response of a passive membrane model to the kinetics of voltage-gated calcium channels that mediate synaptic release. The passive electrical properties of the membrane exhibited lowpass filtering with a relatively high cutoff frequency (nominal value = 717 Hz). This cutoff frequency was dependent on intra-axonal resistance, with shorter and wider axons yielding higher cutoff frequencies. However, we found that the cutoff frequency of bipolar cell synaptic release was primarily limited by the relatively slow opening kinetics of Land T-type calcium channels. The cutoff frequency of calcium currents depended nonlinearly on stimulus amplitude, but remained lower than the cutoff frequency of the passive membrane model for a large range of membrane potential fluctuations. These results suggest that while it may be possible to modulate the membrane potential of bipolar cells over a wide range of stimulus frequencies, synaptic release will only be initiated at the lower end of this range. PMID:21628768

Load and stability measurements on a soft-inplane rotor system incorporating elastomeric lead-lag dampers

NASA Technical Reports Server (NTRS)

Weller, W. H.

1977-01-01

An experimental investigation was conducted of the dynamic response and inplane stability associated with a new soft-inplane helicopter rotor. The unique feature of this rotor was the use of an internal elastomeric damper to restrain the blade inplane motion about the lead-lag hinge. The properties of the elastomer were selected to provide both a nominal first inplane frequency ratio of 0.65 and sufficient damping to eliminate the need for additional external damping sources to prevent ground resonance on a typical fuselage structure. For this investigation a 1/5-scale aeroelastic model was used to represent the rotor. The four-blade model had a diameter of 3.05 m (10 ft) and a solidity of 0.103. The first out-of-plane frequency ratio was 1.06. The model was tested in hover and in forward flight up to an advance ratio of 0.45. At each forward speed the rotor lift was varied up to simulated maneuver conditions. The measured rotor loads and response were within acceptable limits, and no adverse response qualities were observed. Moderate out-of-plane hub moments were measured, even for zero lift, to indicate the beneficial control power available for this design. Blade inplane stability testing indicated that the rotor system damping remained at moderate levels throughout the operating envelope.

A Cryogenic Fluid System Simulation in Support of Integrated Systems Health Management

NASA Technical Reports Server (NTRS)

Barber, John P.; Johnston, Kyle B.; Daigle, Matthew

2013-01-01

Simulations serve as important tools throughout the design and operation of engineering systems. In the context of sys-tems health management, simulations serve many uses. For one, the underlying physical models can be used by model-based health management tools to develop diagnostic and prognostic models. These simulations should incorporate both nominal and faulty behavior with the ability to inject various faults into the system. Such simulations can there-fore be used for operator training, for both nominal and faulty situations, as well as for developing and prototyping health management algorithms. In this paper, we describe a methodology for building such simulations. We discuss the design decisions and tools used to build a simulation of a cryogenic fluid test bed, and how it serves as a core technology for systems health management development and maturation.

Barriers and Facilitators to Being Physically Active on a Rural U.S. Northern Plains American Indian Reservation

PubMed Central

Jahns, Lisa; McDonald, Leander R.; Wadsworth, Ann; Morin, Charles; Liu, Yan

2014-01-01

The objective of the present study was to identify barriers to and facilitators of physical activity among American Indian adults living on a rural, U.S. Northern Plains reservation using the nominal group technique (NGT). NGT is a method of data generation and interpretation that combines aspects of qualitative (free generation of responses) and quantitative (systematic ranking of responses) methodologies. Adults participated in one of two NGT sessions asking about either barriers to (n = 6), or facilitators of (n = 5), being physically active. Participants nominated and ranked 21 barriers and 18 facilitators. Barriers indicated lack of knowledge of how to fit physical activity into a daily schedule, work, caring for family members, and prioritizing sedentary pursuits. Other responses included environmental barriers such as lack of access and transportation to a gym, unsafe walking conditions, and inclement weather. Facilitators to following recommendations included knowledge of health benefits of physical activity and the perception of physical activity as enjoyable, including feeling good when working out. Environmental facilitators included being outdoors walking and biking as well as parks and exercise facilities. Responses provided direction for locally designed community-based programs to promote facilitators and decrease barriers to individual’s engagement in physical activity. PMID:25421064

Barriers and facilitators to being physically active on a rural U.S. Northern Plains American Indian reservation.

PubMed

Jahns, Lisa; McDonald, Leander R; Wadsworth, Ann; Morin, Charles; Liu, Yan

2014-11-21

The objective of the present study was to identify barriers to and facilitators of physical activity among American Indian adults living on a rural, U.S. Northern Plains reservation using the nominal group technique (NGT). NGT is a method of data generation and interpretation that combines aspects of qualitative (free generation of responses) and quantitative (systematic ranking of responses) methodologies. Adults participated in one of two NGT sessions asking about either barriers to (n = 6), or facilitators of (n = 5), being physically active. Participants nominated and ranked 21 barriers and 18 facilitators. Barriers indicated lack of knowledge of how to fit physical activity into a daily schedule, work, caring for family members, and prioritizing sedentary pursuits. Other responses included environmental barriers such as lack of access and transportation to a gym, unsafe walking conditions, and inclement weather. Facilitators to following recommendations included knowledge of health benefits of physical activity and the perception of physical activity as enjoyable, including feeling good when working out. Environmental facilitators included being outdoors walking and biking as well as parks and exercise facilities. Responses provided direction for locally designed community-based programs to promote facilitators and decrease barriers to individual's engagement in physical activity.

Influence of genetic variants associated with body mass index on eating behavior in childhood

PubMed Central

Monnereau, Claire; Jansen, Pauline W; Tiemeier, Henning; Jaddoe, Vincent WV; Felix, Janine F

2017-01-01

Objective Childhood eating behaviors are associated with body mass index (BMI). Recent genome-wide association studies have identified many single nucleotide polymorphisms (SNPs) associated with adult and childhood BMI. We hypothesized that these SNPs also influence eating behavior. Methods In a population-based prospective cohort study among 3,179 children (mean age (standard deviation): 4.0 (0.1) years), we tested two weighted genetic risk scores, based on 15 childhood and 97 adult BMI SNPs, and ten individual appetite and/or satiety related SNPs for association with food fussiness, food responsiveness, enjoyment of food, satiety responsiveness, slowness in eating. Results The 15 SNP-based childhood BMI genetic risk score was not associated with the eating behavior subscales. The 97 SNP-based adult BMI genetic risk score was nominally associated with satiety responsiveness (β: -0.007 standard deviation, 95% confidence interval (CI) -0.013, 0.000). Of the ten individual SNPs, rs11030104 in BDNF and rs10733682 in LMX1B were nominally associated with satiety responsiveness (β: -0.057 standard deviation, 95% CI -0.112, -0.002). Conclusion Our findings do not strongly support the hypothesis that BMI associated SNPs also influence eating behavior at this age. A potential role for BMI SNPs in satiety responsiveness during childhood was observed, however, no associations with the other eating behavior subscales. PMID:28245097

Hybrid adaptive ascent flight control for a flexible launch vehicle

NASA Astrophysics Data System (ADS)

Lefevre, Brian D.

For the purpose of maintaining dynamic stability and improving guidance command tracking performance under off-nominal flight conditions, a hybrid adaptive control scheme is selected and modified for use as a launch vehicle flight controller. This architecture merges a model reference adaptive approach, which utilizes both direct and indirect adaptive elements, with a classical dynamic inversion controller. This structure is chosen for a number of reasons: the properties of the reference model can be easily adjusted to tune the desired handling qualities of the spacecraft, the indirect adaptive element (which consists of an online parameter identification algorithm) continually refines the estimates of the evolving characteristic parameters utilized in the dynamic inversion, and the direct adaptive element (which consists of a neural network) augments the linear feedback signal to compensate for any nonlinearities in the vehicle dynamics. The combination of these elements enables the control system to retain the nonlinear capabilities of an adaptive network while relying heavily on the linear portion of the feedback signal to dictate the dynamic response under most operating conditions. To begin the analysis, the ascent dynamics of a launch vehicle with a single 1st stage rocket motor (typical of the Ares 1 spacecraft) are characterized. The dynamics are then linearized with assumptions that are appropriate for a launch vehicle, so that the resulting equations may be inverted by the flight controller in order to compute the control signals necessary to generate the desired response from the vehicle. Next, the development of the hybrid adaptive launch vehicle ascent flight control architecture is discussed in detail. Alterations of the generic hybrid adaptive control architecture include the incorporation of a command conversion operation which transforms guidance input from quaternion form (as provided by NASA) to the body-fixed angular rate commands needed by the hybrid adaptive flight controller, development of a Newton's method based online parameter update that is modified to include a step size which regulates the rate of change in the parameter estimates, comparison of the modified Newton's method and recursive least squares online parameter update algorithms, modification of the neural network's input structure to accommodate for the nature of the nonlinearities present in a launch vehicle's ascent flight, examination of both tracking error based and modeling error based neural network weight update laws, and integration of feedback filters for the purpose of preventing harmful interaction between the flight control system and flexible structural modes. To validate the hybrid adaptive controller, a high-fidelity Ares I ascent flight simulator and a classical gain-scheduled proportional-integral-derivative (PID) ascent flight controller were obtained from the NASA Marshall Space Flight Center. The classical PID flight controller is used as a benchmark when analyzing the performance of the hybrid adaptive flight controller. Simulations are conducted which model both nominal and off-nominal flight conditions with structural flexibility of the vehicle either enabled or disabled. First, rigid body ascent simulations are performed with the hybrid adaptive controller under nominal flight conditions for the purpose of selecting the update laws which drive the indirect and direct adaptive components. With the neural network disabled, the results revealed that the recursive least squares online parameter update caused high frequency oscillations to appear in the engine gimbal commands. This is highly undesirable for long and slender launch vehicles, such as the Ares I, because such oscillation of the rocket nozzle could excite unstable structural flex modes. In contrast, the modified Newton's method online parameter update produced smooth control signals and was thus selected for use in the hybrid adaptive launch vehicle flight controller. In the simulations where the online parameter identification algorithm was disabled, the tracking error based neural network weight update law forced the network's output to diverge despite repeated reductions of the adaptive learning rate. As a result, the modeling error based neural network weight update law (which generated bounded signals) is utilized by the hybrid adaptive controller in all subsequent simulations. Comparing the PID and hybrid adaptive flight controllers under nominal flight conditions in rigid body ascent simulations showed that their tracking error magnitudes are similar for a period of time during the middle of the ascent phase. Though the PID controller performs better for a short interval around the 20 second mark, the hybrid adaptive controller performs far better from roughly 70 to 120 seconds. Elevating the aerodynamic loads by increasing the force and moment coefficients produced results very similar to the nominal case. However, applying a 5% or 10% thrust reduction to the first stage rocket motor causes the tracking error magnitude observed by the PID controller to be significantly elevated and diverge rapidly as the simulation concludes. In contrast, the hybrid adaptive controller steadily maintains smaller errors (often less than 50% of the corresponding PID value). Under the same sets of flight conditions with flexibility enabled, the results exhibit similar trends with the hybrid adaptive controller performing even better in each case. Again, the reduction of the first stage rocket motor's thrust clearly illustrated the superior robustness of the hybrid adaptive flight controller.

Russian Apartment Building Thermal Response Models for Retrofit Selection and Verification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armstrong, Peter R.; Dirks, James A.; Reilly, Raymond W.

2000-08-21

The Enterprise Housing Divestiture Project (EHDP) aims to identify cost-effective energy efficiency and conservation measures for Russian apartment buildings and to implement these measures in the entire stock of buildings undergoing divestiture in six cities. Short-term measurements of infiltration and exterior wall heat-loss coefficient were made in the cities of Cheropovets, Orenburg, Petrozavodsk, Ryazan, and Vladimir. Long-term monitoring equipment was installed in six or more buildings in the aforementioned and in the city of Volxhov. The results of these measurements will be used to calibrate models used to select optimal retrofit packages and to verify energy savings. The retrofit categoriesmore » representing the largest technical potential in these buildings are envelope, heat recovery, and heating/hot water system improvements. This paper describes efforts to establish a useful thermal model calibration process. The model structures and analytical methods for obtaining building parameters from time series weather, energy use, and thermal response data are developed. Our experience applying these methods to two, nominally identical 5-story apartment buildings in the city of Ryazan is presented. Building envelope UA?s inferred from measured whole-building thermal response data are compared with UA?s based on window and wall U-values (the latter obtained by ASTM in-situ measurements of 20 wall sections in various Ryazan panel buildings) as well. The UA's obtained by these completely independent measurements differ by less than 10%.« less

Evaluation of an advanced physical diagnosis course using consumer preferences methods: the nominal group technique.

PubMed

Coker, Joshua; Castiglioni, Analia; Kraemer, Ryan R; Massie, F Stanford; Morris, Jason L; Rodriguez, Martin; Russell, Stephen W; Shaneyfelt, Terrance; Willett, Lisa L; Estrada, Carlos A

2014-03-01

Current evaluation tools of medical school courses are limited by the scope of questions asked and may not fully engage the student to think on areas to improve. The authors sought to explore whether a technique to study consumer preferences would elicit specific and prioritized information for course evaluation from medical students. Using the nominal group technique (4 sessions), 12 senior medical students prioritized and weighed expectations and topics learned in a 100-hour advanced physical diagnosis course (4-week course; February 2012). Students weighted their top 3 responses (top = 3, middle = 2 and bottom = 1). Before the course, 12 students identified 23 topics they expected to learn; the top 3 were review sensitivity/specificity and high-yield techniques (percentage of total weight, 18.5%), improving diagnosis (13.8%) and reinforce usual and less well-known techniques (13.8%). After the course, students generated 22 topics learned; the top 3 were practice and reinforce advanced maneuvers (25.4%), gaining confidence (22.5%) and learn the evidence (16.9%). The authors observed no differences in the priority of responses before and after the course (P = 0.07). In a physical diagnosis course, medical students elicited specific and prioritized information using the nominal group technique. The course met student expectations regarding education of the evidence-based physical examination, building skills and confidence on the proper techniques and maneuvers and experiential learning. The novel use for curriculum evaluation may be used to evaluate other courses-especially comprehensive and multicomponent courses.

Numerical simulation of large-scale ocean-atmosphere coupling and the ocean's role in climate

NASA Technical Reports Server (NTRS)

Gates, W. L.

1983-01-01

The problem of reducing model generated sigma coordinate data to pressure levels is considered. A mass consistent scheme for performing budget analyses is proposed, wherein variables interpolated to a given pressure level are weighted according to the mass between a nominal pressure level above and either a nominal pressure level below or the Earth's surface, whichever is closer. The method is applied to the atmospheric energy cycle as simulated by the OSU two level atmospheric general circulation model. The results are more realistic than sigma coordinate analyses with respect to eddy decomposition, and are in agreement with the sigma coordinate evaluation of the numerical energy sink. Comparison with less sophisticated budget schemes indicates superiority locally, but not globally.

The application of neural networks to the SSME startup transient

NASA Technical Reports Server (NTRS)

Meyer, Claudia M.; Maul, William A.

1991-01-01

Feedforward neural networks were used to model three parameters during the Space Shuttle Main Engine startup transient. The three parameters were the main combustion chamber pressure, a controlled parameter, the high pressure oxidizer turbine discharge temperature, a redlined parameter, and the high pressure fuel pump discharge pressure, a failure-indicating performance parameter. Network inputs consisted of time windows of data from engine measurements that correlated highly to the modeled parameter. A standard backpropagation algorithm was used to train the feedforward networks on two nominal firings. Each trained network was validated with four additional nominal firings. For all three parameters, the neural networks were able to accurately predict the data in the validation sets as well as the training set.

Transient Region Coverage in the Propulsion IVHM Technology Experiment

NASA Technical Reports Server (NTRS)

Balaban, Edward; Sweet, Adam; Bajwa, Anupa; Maul, William; Fulton, Chris; Chicatelli, amy

2004-01-01

Over the last several years researchers at NASA Glenn and Ames Research Centers have developed a real-time fault detection and isolation system for propulsion subsystems of future space vehicles. The Propulsion IVHM Technology Experiment (PITEX), as it is called follows the model-based diagnostic methodology and employs Livingstone, developed at NASA Ames, as its reasoning engine. The system has been tested on,flight-like hardware through a series of nominal and fault scenarios. These scenarios have been developed using a highly detailed simulation of the X-34 flight demonstrator main propulsion system and include realistic failures involving valves, regulators, microswitches, and sensors. This paper focuses on one of the recent research and development efforts under PITEX - to provide more complete transient region coverage. It describes the development of the transient monitors, the corresponding modeling methodology, and the interface software responsible for coordinating the flow of information between the quantitative monitors and the qualitative, discrete representation Livingstone.

Lift capability prediction for helicopter rotor blade-numerical evaluation

NASA Astrophysics Data System (ADS)

Rotaru, Constantin; Cîrciu, Ionicǎ; Luculescu, Doru

2016-06-01

The main objective of this paper is to describe the key physical features for modelling the unsteady aerodynamic effects found on helicopter rotor blade operating under nominally attached flow conditions away from stall. The unsteady effects were considered as phase differences between the forcing function and the aerodynamic response, being functions of the reduced frequency, the Mach number and the mode forcing. For a helicopter rotor, the reduced frequency at any blade element can't be exactly calculated but a first order approximation for the reduced frequency gives useful information about the degree of unsteadiness. The sources of unsteady effects were decomposed into perturbations to the local angle of attack and velocity field. The numerical calculus and graphics were made in FLUENT and MAPLE soft environments. This mathematical model is applicable for aerodynamic design of wind turbine rotor blades, hybrid energy systems optimization and aeroelastic analysis.

A preliminary assessment of the Titan planetary boundary layer

NASA Technical Reports Server (NTRS)

Allison, Michael

1992-01-01

Results of a preliminary assessment of the characteristic features of the Titan planetary boundary are addressed. These were derived from the combined application of a patched Ekman surface layer model and Rossby number similarity theory. Both these models together with Obukhov scaling, surface speed limits and saltation are discussed. A characteristic Akman depth of approximately 0.7 km is anticipated, with an eddy viscosity approximately equal to 1000 sq cm/s, an associated friction velocity approximately 0.01 m/s, and a surface wind typically smaller than 0.6 m/s. Actual values of these parameters probably vary by as much as a factor of two or three, in response to local temporal variations in surface roughness and stability. The saltation threshold for the windblown injection of approximately 50 micrometer particulates into the atmosphere is less than twice the nominal friction velocity, suggesting that dusty breezes might be an occassional feature of the Titan meteorology.

Autonomous frequency domain identification: Theory and experiment

NASA Technical Reports Server (NTRS)

Yam, Yeung; Bayard, D. S.; Hadaegh, F. Y.; Mettler, E.; Milman, M. H.; Scheid, R. E.

1989-01-01

The analysis, design, and on-orbit tuning of robust controllers require more information about the plant than simply a nominal estimate of the plant transfer function. Information is also required concerning the uncertainty in the nominal estimate, or more generally, the identification of a model set within which the true plant is known to lie. The identification methodology that was developed and experimentally demonstrated makes use of a simple but useful characterization of the model uncertainty based on the output error. This is a characterization of the additive uncertainty in the plant model, which has found considerable use in many robust control analysis and synthesis techniques. The identification process is initiated by a stochastic input u which is applied to the plant p giving rise to the output. Spectral estimation (h = P sub uy/P sub uu) is used as an estimate of p and the model order is estimated using the produce moment matrix (PMM) method. A parametric model unit direction vector p is then determined by curve fitting the spectral estimate to a rational transfer function. The additive uncertainty delta sub m = p - unit direction vector p is then estimated by the cross spectral estimate delta = P sub ue/P sub uu where e = y - unit direction vectory y is the output error, and unit direction vector y = unit direction vector pu is the computed output of the parametric model subjected to the actual input u. The experimental results demonstrate the curve fitting algorithm produces the reduced-order plant model which minimizes the additive uncertainty. The nominal transfer function estimate unit direction vector p and the estimate delta of the additive uncertainty delta sub m are subsequently available to be used for optimization of robust controller performance and stability.

75 FR 25259 - Board of Governors of the Patient-Centered Outcomes Research Institute (PCOR)

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-07

... GOVERNMENT ACCOUNTABILITY OFFICE Board of Governors of the Patient-Centered Outcomes Research Institute (PCOR) AGENCY: Government Accountability Office (GAO). ACTION: Notice on letters of nomination... responsibility for appointing 19 members to the Board of Governors of the Patient-Centered Outcomes Research...

CNTRICS Imaging Biomarkers Final Task Selection: Long-Term Memory and Reinforcement Learning

PubMed Central

Ragland, John D.; Cohen, Neal J.; Cools, Roshan; Frank, Michael J.; Hannula, Deborah E.; Ranganath, Charan

2012-01-01

Functional imaging paradigms hold great promise as biomarkers for schizophrenia research as they can detect altered neural activity associated with the cognitive and emotional processing deficits that are so disabling to this patient population. In an attempt to identify the most promising functional imaging biomarkers for research on long-term memory (LTM), the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS) initiative selected “item encoding and retrieval,” “relational encoding and retrieval,” and “reinforcement learning” as key LTM constructs to guide the nomination process. This manuscript reports on the outcome of the third CNTRICS biomarkers meeting in which nominated paradigms in each of these domains were discussed by a review panel to arrive at a consensus on which of the nominated paradigms could be recommended for immediate translational development. After briefly describing this decision process, information is presented from the nominating authors describing the 4 functional imaging paradigms that were selected for immediate development. In addition to describing the tasks, information is provided on cognitive and neural construct validity, sensitivity to behavioral or pharmacological manipulations, availability of animal models, psychometric characteristics, effects of schizophrenia, and avenues for future development. PMID:22102094

Multiplicity Control in Structural Equation Modeling: Incorporating Parameter Dependencies

ERIC Educational Resources Information Center

Smith, Carrie E.; Cribbie, Robert A.

2013-01-01

When structural equation modeling (SEM) analyses are conducted, significance tests for all important model relationships (parameters including factor loadings, covariances, etc.) are typically conducted at a specified nominal Type I error rate ([alpha]). Despite the fact that many significance tests are often conducted in SEM, rarely is…

Fathead Minnow Steroidogenesis: In Silico Analyses Reveals Tradeoffs Between Nominal Target Efficacy and Robustness to Cross-talk

EPA Science Inventory

This paper presents the formulation and evaluation of a mechanistic mathematical model of fathead minnow ovarian steroidogenesis. The model presented in the present study was adpated from other models developed as part of an integrated, multi-disciplinary computational toxicolog...

Two-phase flow in the cooling circuit of a cryogenic rocket engine

NASA Astrophysics Data System (ADS)

Preclik, D.

1992-07-01

Transient two-phase flow was investigated for the hydrogen cooling circuit of the HM7 rocket engine. The nuclear reactor code ATHLET/THESEUS was adapted to cryogenics and applied to both principal and prototype experiments for validation and simulation purposes. The cooling circuit two-phase flow simulation focused on the hydrogen prechilling and pump transient phase prior to ignition. Both a single- and a multichannel model were designed and employed for a valve leakage flow, a nominal prechilling flow, and a prechilling with a subsequent pump-transient flow. The latter case was performed in order to evaluate the difference between a nominal and a delayed turbo-pump start-up. It was found that an extension of the nominal prechilling sequence in the order of 1 second is sufficient to finally provide for liquid injection conditions of hydrogen which, as commonly known, is undesirable for smooth ignition and engine starting transients.

A guidance and navigation system for continuous low thrust vehicles. M.S. Thesis

NASA Technical Reports Server (NTRS)

Tse, C. J. C.

1973-01-01

A midcourse guidance and navigation system for continuous low thrust vehicles is described. A set of orbit elements, known as the equinoctial elements, are selected as the state variables. The uncertainties are modelled statistically by random vector and stochastic processes. The motion of the vehicle and the measurements are described by nonlinear stochastic differential and difference equations respectively. A minimum time nominal trajectory is defined and the equation of motion and the measurement equation are linearized about this nominal trajectory. An exponential cost criterion is constructed and a linear feedback guidance law is derived to control the thrusting direction of the engine. Using this guidance law, the vehicle will fly in a trajectory neighboring the nominal trajectory. The extended Kalman filter is used for state estimation. Finally a short mission using this system is simulated. The results indicate that this system is very efficient for short missions.

Pretest thermal analysis of the Tuff Water Migration/In-Situ Heater Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bulmer, B.M.

This report describes the pretest thermal analysis for the Tuff Water Migration/In-Situ Heater Experiment to be conducted in welded tuff in G-tunnel, Nevada Test Site. The parametric thermal modeling considers variable boiling temperature, tuff thermal conductivity, tuff emissivity, and heater operating power. For nominal tuff properties, some near field boiling is predicted for realistic operating power. However, the extent of boiling will be strongly determined by the ambient (100% water saturated) rock thermal conductivity. In addition, the thermal response of the heater and of the tuff within the dry-out zone (i.e., bounded by boiling isotherm) is dependent on the temperaturemore » variation of rock conductivity as well as the extent of induced boiling.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winterbone, D.E.; Richards, P.

A microprocessor controlled test bed was built for steady state mapping of petrol engines using a sweep mapping technique. The addition of an electric motor to the fast acting dynamometer allowed rapid load changes to be applied at nominally constant speed. This made it possible to consider the dynamic behaviour of the power generation sub-system of the engine. The engine was initially subjected to ramp changes of torque but these did not give consistent results. PRBS signals were then used for the same variable and a mathematical transfer function model developed for the engine power system. The engine was consideredmore » both as a continuous and sample data system. Results will be presented which show fuel management has an appreciable effect on the engine dynamic response.« less

Modeling and semi-active fuzzy control of magnetorheological elastomer-based isolator for seismic response reduction

NASA Astrophysics Data System (ADS)

Nguyen, Xuan Bao; Komatsuzaki, Toshihiko; Iwata, Yoshio; Asanuma, Haruhiko

2018-02-01

In this paper, a magnetorheological elastomer (MRE) based isolator was investigated to mitigate excessive vibrations in structures during seismic events. The primary objectives of this research are to propose a numerical model that expresses viscoelastic behaviors of the MRE and predict operation process of the MRE-based isolator for future design of isolator systems for various technical applications. Despite the simplicity in parameter definition in comparison to the conventional models, the proposed model works efficiently in a wide range of frequencies and amplitudes. The model consists of the following components: viscoelasticity of host MRE, magnetic field-induced property, nominal viscosity as well as high stiffness in low excitation frequency that are modeled in analogy with a standard linear solid model (Zener model), a stiffness variable spring, and a smooth Coulomb friction, respectively. Furthermore, a semi-active fuzzy controller was designed to enhance the performance of the isolator in suppressing structural vibrations. The control strategy was built to determine the command applied current. The controller is completely adequate for handling the nonlinearity of the isolator and works independently with the building structure. The efficiency of the MRE-based isolator was evaluated by the responses of the scaled building under seismic excitation. Numerical and experimental results show that the isolator accompanied with a fuzzy controller remarkably reduces the relative displacement and absolute acceleration of the scaled building compared to passive-off and passive-on cases.

Resolving Off-Nominal Situations in Schedule-Based Terminal Area Operations: Results from a Human-in-the-Loop Simulation

NASA Technical Reports Server (NTRS)

Mercer, Joey; Callantine, Todd; Martin, Lynne

2012-01-01

A recent human-in-the-loop simulation in the Airspace Operations Laboratory (AOL) at NASA's Ames Research Center investigated the robustness of Controller-Managed Spacing (CMS) operations. CMS refers to AOL-developed controller tools and procedures for enabling arrivals to conduct efficient Optimized Profile Descents with sustained high throughput. The simulation provided a rich data set for examining how a traffic management supervisor and terminal-area controller participants used the CMS tools and coordinated to respond to off-nominal events. This paper proposes quantitative measures for characterizing the participants responses. Case studies of go-around events, replicated during the simulation, provide insights into the strategies employed and the role the CMS tools played in supporting them.

Instituting organizational learning for quality improvement through strategic planning nominal group processes.

PubMed

White, D B

2000-01-01

Healthcare managers are faced with unprecedented challenges as characterized by managed care constraints, downsizing, increased client needs, and a society demanding more responsive services. Managers must initiate change for quality, efficiency, and survival. This article provides information and strategies for (a) assessing the change readiness of an organization, (b) conducting an organizational diagnosis, (c) instituting a team culture, (d) developing a change strategy, (e) integrating the strategy with a quality improvement process, and (f) identifying the leadership skills to implement organization renewal. Nominal group processes, namely, SWOT and the Search Conference, are described, and case examples are provided. The implementation strategies have been used successfully in a variety of milieus; practical advice for success is described in detail.

LITHO1.0: An Updated Crust and Lithosphere Model of the Earth

NASA Astrophysics Data System (ADS)

Masters, G.; Ma, Z.; Laske, G.; Pasyanos, M. E.

2011-12-01

We are developing LITHO1.0: an updated crust and lithosphere model of the Earth. The overall plan is to take the popular CRUST2.0 model - a global model of crustal structure with a relatively poor representation of the uppermost mantle - and improve its nominal resolution to 1 degree and extend the model to include lithospheric structure. The new model, LITHO1.0, will be constrained by many different datasets including extremely large new datasets of relatively short period group velocity data. Other data sets include (but are not limited to) compilations of receiver function constraints and active source studies. To date, we have completed the compilation of extremely large global datasets of group velocity for Rayleigh and Love waves from 10mHz to 40mHz using a cluster analysis technique. We have also extended the method to measure phase velocity and are complementing the group velocity with global data sets of longer period phase data that help to constrain deep lithosphere properties. To model these data, we require a starting model for the crust at a nominal resolution of 1 degree. This has been developed by constructing a map of crustal thickness using data from receiver function and active source experiments where available, and by using CRUST2.0 where other constraints are not available. Particular care has been taken to make sure that the locations of sharp changes in crustal thickness are accurately represented. This map is then used as a template to extend CRUST2.0 to 1 degree nominal resolution and to develop starting maps of all crustal properties. We are currently modeling the data using two techniques. The first is a linearized inversion about the 3D crustal starting model. Note that it is important to use local eigenfunctions to compute Frechet derivatives due to the extreme variations in crustal structure. Another technique uses a targeted grid search method. A preliminary model for the crustal part of the model will be presented.

An Intelligent Decision System for Intraoperative Somatosensory Evoked Potential Monitoring.

PubMed

Fan, Bi; Li, Han-Xiong; Hu, Yong

2016-02-01

Somatosensory evoked potential (SEP) is a useful, noninvasive technique widely used for spinal cord monitoring during surgery. One of the main indicators of a spinal cord injury is the drop in amplitude of the SEP signal in comparison to the nominal baseline that is assumed to be constant during the surgery. However, in practice, the real-time baseline is not constant and may vary during the operation due to nonsurgical factors, such as blood pressure, anaesthesia, etc. Thus, a false warning is often generated if the nominal baseline is used for SEP monitoring. In current practice, human experts must be used to prevent this false warning. However, these well-trained human experts are expensive and may not be reliable and consistent due to various reasons like fatigue and emotion. In this paper, an intelligent decision system is proposed to improve SEP monitoring. First, the least squares support vector regression and multi-support vector regression models are trained to construct the dynamic baseline from historical data. Then a control chart is applied to detect abnormalities during surgery. The effectiveness of the intelligent decision system is evaluated by comparing its performance against the nominal baseline model by using the real experimental datasets derived from clinical conditions.

Aircraft control surface failure detection and isolation using the OSGLR test. [orthogonal series generalized likelihood ratio

NASA Technical Reports Server (NTRS)

Bonnice, W. F.; Motyka, P.; Wagner, E.; Hall, S. R.

1986-01-01

The performance of the orthogonal series generalized likelihood ratio (OSGLR) test in detecting and isolating commercial aircraft control surface and actuator failures is evaluated. A modification to incorporate age-weighting which significantly reduces the sensitivity of the algorithm to modeling errors is presented. The steady-state implementation of the algorithm based on a single linear model valid for a cruise flight condition is tested using a nonlinear aircraft simulation. A number of off-nominal no-failure flight conditions including maneuvers, nonzero flap deflections, different turbulence levels and steady winds were tested. Based on the no-failure decision functions produced by off-nominal flight conditions, the failure detection and isolation performance at the nominal flight condition was determined. The extension of the algorithm to a wider flight envelope by scheduling on dynamic pressure and flap deflection is examined. Based on this testing, the OSGLR algorithm should be capable of detecting control surface failures that would affect the safe operation of a commercial aircraft. Isolation may be difficult if there are several surfaces which produce similar effects on the aircraft. Extending the algorithm over the entire operating envelope of a commercial aircraft appears feasible.

ELECTRIC AND MAGNETIC FIELDS <100 KHZ IN ELECTRIC AND GASOLINE-POWERED VEHICLES.

PubMed

Tell, Richard A; Kavet, Robert

2016-12-01

Measurements were conducted to investigate electric and magnetic fields (EMFs) from 120 Hz to 10 kHz and 1.2 to 100 kHz in 9 electric or hybrid vehicles and 4 gasoline vehicles, all while being driven. The range of fields in the electric vehicles enclosed the range observed in the gasoline vehicles. Mean magnetic fields ranged from nominally 0.6 to 3.5 µT for electric/hybrids depending on the measurement band compared with nominally 0.4 to 0.6 µT for gasoline vehicles. Mean values of electric fields ranged from nominally 2 to 3 V m -1 for electric/hybrid vehicles depending on the band, compared with 0.9 to 3 V m -1 for gasoline vehicles. In all cases, the fields were well within published exposure limits for the general population. The measurements were performed with Narda model EHP-50C/EHP-50D EMF analysers that revealed the presence of spurious signals in the EHP-50C unit, which were resolved with the EHP-50D model. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Clinical photographic observation of plantar corns and callus associated with a nominal scale classification and inter- observer reliability study in a student population.

PubMed

Tollafield, David R

2017-01-01

The management of plantar corns and callus has a low cost-benefit with reduced prioritisation in healthcare. The distinction between types of keratin lesions that forms corns and callus has attracted limited interest. Observation is imperative to improving diagnostic predictions and a number of studies point to some confusion as to how best to achieve this. The use of photographic observation has been proposed to improve our understanding of intractable keratin lesions. Students from a podiatry school reviewed photographs where plantar keratin lesions were divided into four nominal groups; light callus (Grade 1), heavy defined callus (Grade 2), concentric keratin plugs (Grade 3) and callus with deeper density changes under the forefoot (Grade 4). A group of 'experts' assigned from qualified podiatrists validated the observer rated responses by the students. Cohen's weighted statistic (k) was used to measure inter-observer reliability. First year students (unskilled) performed less well when viewing photographs ( k  = 0.33) compared to third year students (semi-skilled, k  = 0.62). The experts performed better than students ( k  = 0.88) providing consistency with wound care models in other studies. Improved clinical annotation of clinical features, supported by classification of keratin- based lesions, combined with patient outcome tools, could improve the scientific rationale to prioritise patient care. Problems associated with photographic assessment involves trying to differentiate similar lesions without the benefit of direct palpation. Direct observation of callus with and without debridement requires further investigation alongside the model proposed in this paper.

77 FR 52330 - Request for Additional Nominations of Candidates for the EPA's Science Advisory Board (SAB...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-29

... person or organization may nominate qualified persons to be considered for appointment to this advisory committee. Individuals may self-nominate. Nominations should be submitted in electronic format (preferred) following the instructions for ``Nominating Experts to the Chemical Assessment Advisory Committee'' provided...

76 FR 71561 - Request for Nominations of Candidates to the EPA's Science Advisory Board (SAB) Chemical...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-18

... nominate qualified persons to be considered for appointment to this advisory committee. Individuals may self-nominate. Nominations should be submitted in electronic format (preferred) following the instructions for ``Nominating Experts to the Chemical Assessment Advisory Committee'' provided on the SAB Web...

Implications of Systematic Nominator Missingness for Peer Nomination Data

ERIC Educational Resources Information Center

Babcock, Ben; Marks, Peter E. L.; van den Berg, Yvonne H. M.; Cillessen, Antonius H. N.

2018-01-01

Missing data are a persistent problem in psychological research. Peer nomination data present a unique missing data problem, because a nominator's nonparticipation results in missing data for other individuals in the study. This study examined the range of effects of systematic nonparticipation on the correlations between peer nomination data when…

Nominalizations in Spanish. Studies in Linguistics and Language Learning, Volume V.

ERIC Educational Resources Information Center

Falk, Julia Sableski

Using methods developed in transformational generative grammar, three types of nominal constructions in Spanish are treated in this paper: Fact nominalizations ("[El] Escribir es agradable"), Manner nominalizations ("El tocar [de la mujer] es agradable"), and Abstract noun nominalizations ("La construccion rapida de esta escuela es dudosa"). While…

Recent Progress in Understanding the Shock Response of Ferroelectric Ceramics

NASA Astrophysics Data System (ADS)

Setchell, R. E.

2002-07-01

Ferroelectric ceramics exhibit a permanent remanent polarization, and shock depoling of these materials to achieve pulsed sources of electrical power was proposed in the late 1950s. During the following twenty years, extensive studies were conducted to examine the shock response of ferroelectric ceramics primarily based on lead zirconate titanate (PZT). Under limited conditions, relatively simple analytical models were found to adequately describe the observed electrical behavior. A more complex behavior was indicated over broader conditions, however, resulting in the incorporation of shock-induced conductivity and dielectric relaxation into analytical models. Unfortunately, few experimental studies were undertaken over the next twenty years, and the development of more comprehensive models was inhibited. In recent years, a strong interest in advancing numerical simulation capabilities has motivated new experimental studies and corresponding model development. More than seventy gas gun experiments have examined several ferroelectric ceramics, with most experiments on lead zirconate titanate having a Zr:Ti ratio of 95:5 and modified with 2% niobium (PZT 95/5). This material is nominally ferroelectric but is near an antiferroelectric phase boundary, and depoling results from a shock-driven phase transition. Experiments have examined unpoled, normally poled, and axially poled PZT 95/5 over broad ranges of shock pressure and peak electric field. The extensive base of new data provides quantitative insights into both the stress and field dependencies of depoling kinetics, and the significance of pore collapse at higher stresses. The results are being actively utilized to develop and refine material response models used in numerical simulations of pulsed power devices.

77 FR 74204 - Commercial Leasing for Wind Power on the Outer Continental Shelf Offshore North Carolina-Call for...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-13

...BOEM invites the submission of nominations for commercial wind leases that would allow a lessee to propose the construction of a wind energy project on the Outer Continental Shelf (OCS) offshore North Carolina, and to develop the project if approved after further environmental review. Although this announcement is not itself a leasing announcement, the Call Areas described herein, or portions thereof, may be available for future leasing. BOEM will use responses to this Call to gauge specific interest in acquiring commercial wind leases in some or all of the Call Areas, as required by 43 U.S.C. 1337(p)(3). Parties wishing to submit a nomination in response to this Call should submit detailed and specific information in response to the requirements described in the section entitled, ``Required Nomination Information.'' This announcement also requests comments and information from interested and affected parties about site conditions, resources, and multiple uses in close proximity to, or within, the Call Areas that would be relevant to BOEM's review of any nominations submitted and/or to BOEM's subsequent decision to offer all or part of the Call Areas for commercial wind leasing. The information that BOEM is requesting is described in the section of this Call entitled, ``Requested Information from Interested or Affected Parties.'' This Call is published pursuant to subsection 8(p)(3) of the OCS Lands Act, 43 U.S.C. 1337(p)(3), which was added by section 388 of the Energy Policy Act of 2005 (EPAct), as well as the implementing regulations at 30 CFR part 585. The Call Areas described in this notice are located on the OCS offshore North Carolina and are delineated as Wilmington-West, Wilmington-East and Kitty Hawk (formerly referred to as North Carolina Planning Areas 1, 2, and 5, respectively, during BOEM's North Carolina offshore wind planning efforts). The three Call Areas include 195 whole OCS blocks and 60 partial blocks in total and comprise approximately 1,441 square nautical miles (494,016 hectares). These Call Areas were established in consultation with the BOEM North Carolina Renewable Energy Intergovernmental Task Force (Task Force). A detailed description of the areas and how they were developed is described in the section of this Call entitled, ``Description of the Area.''

Peer Advising in Agricultural Education: A Supplement to Faculty Advising.

ERIC Educational Resources Information Center

Flores, Bob; Weeks, William

Peer Advising in Agricultural Education has been operating since the Fall Semester, 1987, at Texas A & M University. The program involves several undergraduate students nominated by faculty, who are supervised by two doctoral students. Responsibilities of the peer advisors include informing students of campus procedures, assisting in…

76 FR 45555 - Nominations to the FIFRA Scientific Advisory Panel; Request for Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-29

.... Vasiliou's major research interest has been the cellular responses to oxidative stress induced by physical... to novel host plants and agricultural pesticides. This work has been applied to increase... from the University of Nebraska; PhD Plant Physiological Ecology from the University of Oklahoma. iii...

77 FR 23749 - Call for Nominations for Resource Advisory Councils

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-20

... elected office, employees of a state agency responsible for management of natural resources..., representatives of academia who are employed in natural sciences, and the public-at-large. Individuals may..., resources, and facilities administered by the BLM. Mike Pool, Deputy Director. [FR Doc. 2012-9583 Filed 4-19...

Discourses of Whiteness: White Students at Catholic Women's Colleges (Dis)Engaging Race

ERIC Educational Resources Information Center

Ropers-Huilman, Rebecca; Winters, Kelly T.; Enke, Kathryn A. E.

2013-01-01

To better understand how White college women understand and are influenced by whiteness, we discursively analyzed data from interviews and focus groups with 25 White seniors at two Catholic women's colleges. Findings suggest that participants understood whiteness through discourses of insignificance, nominal difference, responsibility, and…

7 CFR 983.42 - Initial members and nomination of successor members.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AGRICULTURE PISTACHIOS GROWN IN CALIFORNIA, ARIZONA, AND NEW MEXICO Administrative Committee § 983.42 Initial... pistachios processed by that handler during the two production years preceding the production year in which... assessed weight of pistachios shall be credited to the handler responsible under the order for the payment...

Finding Proof in the Pudding: the Viability of Reform in Higher Education.

ERIC Educational Resources Information Center

Change, 1997

1997-01-01

Describes the Pew Charitable Trusts' Pew Leadership Award for revitalization and reform in higher education and summarizes characteristics of the 45 nominated institutions. The institutions develop portfolios documenting accomplishments in the areas of curriculum redesign, faculty roles and responsibilities, and resource reallocation. Profiles the…

78 FR 35037 - Request for Nominations of Candidates To Serve on the Board of Scientific Counselors, Office of...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-11

...; medicine, epidemiology, laboratory science, informatics, behavioral science, social science, engineering... international public health partners. The BSC ( http://www.cdc.gov/phpr/science/counselors.htm ) provides advice... of Science and Public Health Practice, Office of Preparedness and Emergency Response, Centers for...

76 FR 45292 - New Agency Information Collection for Solicitation of Nominations for the Advisory Board for...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-28

... Exceptional Children under the Individuals with Disabilities Education Improvement Act. This notice is not... Exceptional Children under the Individuals with Disabilities Education Improvement Act. The information... expertise on the education of Indian children with disabilities. Response is required to obtain a benefit...

Systemic Patterns in Bullying and Victimization

ERIC Educational Resources Information Center

Chan, John H. F.

2006-01-01

Using a new non-anonymous questionnaire and a nomination method by which victims were asked to name their aggressors, Chan (2002) collated the responses from individual victims to produce name-clusters that were studied for systemic patterns of bullying and victimization within the whole-school community. Three such patterns emerged: serial…

75 FR 29317 - Response to Comments on the Second Round of Nominated Sites to the National System of MPAs

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-25

... support the effective stewardship, conservation, restoration, sustainable use, and public understanding... be established by managing agencies to fill key conservation gaps in important ocean areas. FOR..., commonwealth, territorial, tribal and/or local governments that collectively enhance conservation of the nation...

Policy and Procedures, University of Rhode Island Foundation.

ERIC Educational Resources Information Center

Leslie, James W.

A guide to policies and procedures of the University of Rhode Island Foundation is presented. Attention is directed to the following concerns: fund-raising policies, the act incorporating the University of Rhode Island Foundation, by-laws, dual signature system, nominating committee responsibilities and procedures, policy and guidelines for the…

22 CFR 72.14 - Nominal possession; property not normally taken into physical possession.

Code of Federal Regulations, 2010 CFR

2010-04-01

... possession. (a) When a consular officer take articles of a decedent's personal property from a foreign... Department discharging the consular officer of any responsibility for the articles transferred. (b) A... effects; (2) Motor vehicles, airplanes or watercraft; (3) Toiletries, such as toothpaste or razors; (4...

Perceived Similarity among Adolescent Friends: The Role of Reciprocity, Friendship Quality, and Gender

ERIC Educational Resources Information Center

Linden-Andersen, Stine; Markiewicz, Dorothy; Doyle, Anna-Beth

2009-01-01

Perceived similarity of personality in same-sex friends was examined in a sample of 124 adolescents (63 girls). Adolescents rated themselves and a nominated friend (n = 42 reciprocated, 82 non-reciprocated dyads) on developmentally relevant personality items assessing autonomy, prosociality, and responsive caregiving. Results from hierarchical…

78 FR 59698 - Solicitation of Nominations for Membership on the Secretary's Advisory Committee on Human...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-27

... provides advice relating to the responsible conduct of research involving human subjects with particular... Secretary's Advisory Committee on Human Research Protections AGENCY: Department of Health and Human Services, Office of the Secretary, Office of the Assistant Secretary for Health, Office for Human Research...

76 FR 78660 - Solicitation of Nominations for Membership on the Secretary's Advisory Committee on Human...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-19

.... Specifically, the Committee provides advice relating to the responsible conduct of research involving human... Secretary's Advisory Committee on Human Research Protections AGENCY: Office for Human Research Protections... Human Research Protections (OHRP), a program office in the Office of the Assistant Secretary for Health...

Spacecraft Debris Avoidance Using Positively Invariant Constraint Admissible Sets (Postprint)

DTIC Science & Technology

2013-08-14

LTV); Clohessy - Wiltshire -Hill (CWH) 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE...linear time-invariant Clohessy - Wiltshire -Hill (CWH) equations. See Ref. 13. A nominal circular orbit is assumed in this work. 2 Approved for public

Q-adjusting technique applied to vertical deflections estimation in a single-axis rotation INS/GPS integrated system

NASA Astrophysics Data System (ADS)

Zhu, Jing; Wang, Xingshu; Wang, Jun; Dai, Dongkai; Xiong, Hao

2016-10-01

Former studies have proved that the attitude error in a single-axis rotation INS/GPS integrated system tracks the high frequency component of the deflections of the vertical (DOV) with a fixed delay and tracking error. This paper analyses the influence of the nominal process noise covariance matrix Q on the tracking error as well as the response delay, and proposed a Q-adjusting technique to obtain the attitude error which can track the DOV better. Simulation results show that different settings of Q lead to different response delay and tracking error; there exists optimal Q which leads to a minimum tracking error and a comparatively short response delay; for systems with different accuracy, different Q-adjusting strategy should be adopted. In this way, the DOV estimation accuracy of using the attitude error as the observation can be improved. According to the simulation results, the DOV estimation accuracy after using the Q-adjusting technique is improved by approximate 23% and 33% respectively compared to that of the Earth Model EGM2008 and the direct attitude difference method.

The response of rotating machinery to external random vibration

NASA Technical Reports Server (NTRS)

Tessarzik, J. M.; Chiang, T.; Badgley, R. H.

1974-01-01

A high-speed turbogenerator employing gas-lubricated hydrodynamic journal and thrust bearings was subjected to external random vibrations for the purpose of assessing bearing performance in a dynamic environment. The pivoted-pad type journal bearings and the step-sector thrust bearing supported a turbine-driven rotor weighing approximately twenty-one pounds at a nominal operating speed of 36,000 rpm. The response amplitudes of both the rigid-supported and flexible-supported bearing pads, the gimballed thrust bearing, and the rotor relative to the machine casing were measured with capacitance type displacement probes. Random vibrations were applied by means of a large electrodynamic shaker at input levels ranging between 0.5 g (rms) and 1.5 g (rms). Vibrations were applied both along and perpendicular to the rotor axis. Response measurements were analyzed for amplitude distribution and power spectral density. Experimental results compare well with calculations of amplitude power spectral density made for the case where the vibrations were applied along the rotor axis. In this case, the rotor-bearing system was treated as a linear, three-mass model.

Shock tube and chemical kinetic modeling study of the oxidation of 2,5-dimethylfuran.

PubMed

Sirjean, Baptiste; Fournet, René; Glaude, Pierre-Alexandre; Battin-Leclerc, Frédérique; Wang, Weijing; Oehlschlaeger, Matthew A

2013-02-21

A detailed kinetic model describing the oxidation of 2,5-dimethylfuran (DMF), a potential second-generation biofuel, is proposed. The kinetic model is based upon quantum chemical calculations for the initial DMF consumption reactions and important reactions of intermediates. The model is validated by comparison to new DMF shock tube ignition delay time measurements (over the temperature range 1300-1831 K and at nominal pressures of 1 and 4 bar) and the DMF pyrolysis speciation measurements of Lifshitz et al. [ J. Phys. Chem. A 1998 , 102 ( 52 ), 10655 - 10670 ]. Globally, modeling predictions are in good agreement with the considered experimental targets. In particular, ignition delay times are predicted well by the new model, with model-experiment deviations of at most a factor of 2, and DMF pyrolysis conversion is predicted well, to within experimental scatter of the Lifshitz et al. data. Additionally, comparisons of measured and model predicted pyrolysis speciation provides validation of theoretically calculated channels for the oxidation of DMF. Sensitivity and reaction flux analyses highlight important reactions as well as the primary reaction pathways responsible for the decomposition of DMF and formation and destruction of key intermediate and product species.

A proposed Kalman filter algorithm for estimation of unmeasured output variables for an F100 turbofan engine

NASA Technical Reports Server (NTRS)

Alag, Gurbux S.; Gilyard, Glenn B.

1990-01-01

To develop advanced control systems for optimizing aircraft engine performance, unmeasurable output variables must be estimated. The estimation has to be done in an uncertain environment and be adaptable to varying degrees of modeling errors and other variations in engine behavior over its operational life cycle. This paper represented an approach to estimate unmeasured output variables by explicitly modeling the effects of off-nominal engine behavior as biases on the measurable output variables. A state variable model accommodating off-nominal behavior is developed for the engine, and Kalman filter concepts are used to estimate the required variables. Results are presented from nonlinear engine simulation studies as well as the application of the estimation algorithm on actual flight data. The formulation presented has a wide range of application since it is not restricted or tailored to the particular application described.

A STUDY OF DUST AND GAS AT MARS FROM COMET C/2013 A1 (SIDING SPRING)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelley, Michael S. P.; Farnham, Tony L.; Bodewits, Dennis

Although the nucleus of comet C/2013 A1 (Siding Spring) will safely pass Mars in 2014 October, the dust in the coma and tail will more closely approach the planet. Using a dynamical model of comet dust, we estimate the impact fluence. Based on our nominal model no impacts are expected at Mars. Relaxing our nominal model's parameters, the fluence is no greater than ∼10{sup –7} grains m{sup –2} for grain radii larger than 10 μm. Mars-orbiting spacecraft are unlikely to be impacted by large dust grains, but Mars may receive as many as ∼10{sup 7} grains, or ∼100 kg of total dust.more » We also estimate the flux of impacting gas molecules commonly observed in comet comae.« less

Observational attachment theory-based parenting measures predict children's attachment narratives independently from social learning theory-based measures.

PubMed

Matias, Carla; O'Connor, Thomas G; Futh, Annabel; Scott, Stephen

2014-01-01

Conceptually and methodologically distinct models exist for assessing quality of parent-child relationships, but few studies contrast competing models or assess their overlap in predicting developmental outcomes. Using observational methodology, the current study examined the distinctiveness of attachment theory-based and social learning theory-based measures of parenting in predicting two key measures of child adjustment: security of attachment narratives and social acceptance in peer nominations. A total of 113 5-6-year-old children from ethnically diverse families participated. Parent-child relationships were rated using standard paradigms. Measures derived from attachment theory included sensitive responding and mutuality; measures derived from social learning theory included positive attending, directives, and criticism. Child outcomes were independently-rated attachment narrative representations and peer nominations. Results indicated that Attachment theory-based and Social Learning theory-based measures were modestly correlated; nonetheless, parent-child mutuality predicted secure child attachment narratives independently of social learning theory-based measures; in contrast, criticism predicted peer-nominated fighting independently of attachment theory-based measures. In young children, there is some evidence that attachment theory-based measures may be particularly predictive of attachment narratives; however, no single model of measuring parent-child relationships is likely to best predict multiple developmental outcomes. Assessment in research and applied settings may benefit from integration of different theoretical and methodological paradigms.

Molecular Genetics of Successful Smoking Cessation: Convergent Genome-Wide Association Study Results

PubMed Central

Uhl, George R.; Liu, Qing-Rong; Drgon, Tomas; Johnson, Catherine; Walther, Donna; Rose, Jed E.; David, Sean P.; Niaura, Ray; Lerman, Caryn

2008-01-01

Context Smoking remains a major public health problem. Twin studies indicate that the ability to quit smoking is substantially heritable, with genetics that overlap modestly with the genetics of vulnerability to dependence on addictive substances. Objectives To identify replicated genes that facilitate smokers’ abilities to achieve and sustain abstinence from smoking (hereinafter referred to as quit-success genes) found in more than 2 genome-wide association (GWA) studies of successful vs unsuccessful abstainers, and, secondarily, to nominate genes for selective involvement in smoking cessation success with bupropion hydrochloride vs nicotine replacement therapy (NRT). Design The GWA results in subjects from 3 centers, with secondary analyses of NRT vs bupropion responders. Setting Outpatient smoking cessation trial participants from 3 centers. Participants European American smokers who successfully vs unsuccessfully abstain from smoking with biochemical confirmation in a smoking cessation trial using NRT, bupropion, or placebo (N=550). Main Outcome Measures Quit-success genes, reproducibly identified by clustered nominally positive single-nucleotide polymorphisms (SNPs) in more than 2 independent samples with significant P values based on Monte Carlo simulation trials. The NRT-selective genes were nominated by clustered SNPs that display much larger t values for NRT vs placebo comparisons. The bupropion-selective genes were nominated by bupropion-selective results. Results Variants in quit-success genes are likely to alter cell adhesion, enzymatic, transcriptional, structural, and DNA, RNA, and/or protein-handling functions. Quit-success genes are identified by clustered nominally positive SNPs from more than 2 samples and are unlikely to represent chance observations (Monte Carlo P < .0003). These genes display modest overlap with genes identified in GWA studies of dependence on addictive substances and memory. Conclusions These results support polygenic genetics for success in abstaining from smoking, overlap with genetics of substance dependence and memory, and nominate gene variants for selective influences on therapeutic responses to bupropion vs NRT. Molecular genetics should help match the types and/or intensity of anti-smoking treatments with the smokers most likely to benefit from them. PMID:18519826

A Model Stitching Architecture for Continuous Full Flight-Envelope Simulation of Fixed-Wing Aircraft and Rotorcraft from Discrete Point Linear Models

DTIC Science & Technology

2016-04-01

incorporated with nonlinear elements to produce a continuous, quasi -nonlinear simulation model. Extrapolation methods within the model stitching architecture...Simulation Model, Quasi -Nonlinear, Piloted Simulation, Flight-Test Implications, System Identification, Off-Nominal Loading Extrapolation, Stability...incorporated with nonlinear elements to produce a continuous, quasi -nonlinear simulation model. Extrapolation methods within the model stitching

Application of Statistically Derived CPAS Parachute Parameters

NASA Technical Reports Server (NTRS)

Romero, Leah M.; Ray, Eric S.

2013-01-01

The Capsule Parachute Assembly System (CPAS) Analysis Team is responsible for determining parachute inflation parameters and dispersions that are ultimately used in verifying system requirements. A model memo is internally released semi-annually documenting parachute inflation and other key parameters reconstructed from flight test data. Dispersion probability distributions published in previous versions of the model memo were uniform because insufficient data were available for determination of statistical based distributions. Uniform distributions do not accurately represent the expected distributions since extreme parameter values are just as likely to occur as the nominal value. CPAS has taken incremental steps to move away from uniform distributions. Model Memo version 9 (MMv9) made the first use of non-uniform dispersions, but only for the reefing cutter timing, for which a large number of sample was available. In order to maximize the utility of the available flight test data, clusters of parachutes were reconstructed individually starting with Model Memo version 10. This allowed for statistical assessment for steady-state drag area (CDS) and parachute inflation parameters such as the canopy fill distance (n), profile shape exponent (expopen), over-inflation factor (C(sub k)), and ramp-down time (t(sub k)) distributions. Built-in MATLAB distributions were applied to the histograms, and parameters such as scale (sigma) and location (mu) were output. Engineering judgment was used to determine the "best fit" distribution based on the test data. Results include normal, log normal, and uniform (where available data remains insufficient) fits of nominal and failure (loss of parachute and skipped stage) cases for all CPAS parachutes. This paper discusses the uniform methodology that was previously used, the process and result of the statistical assessment, how the dispersions were incorporated into Monte Carlo analyses, and the application of the distributions in trajectory benchmark testing assessments with parachute inflation parameters, drag area, and reefing cutter timing used by CPAS.

Estimating and Modelling Bias of the Hierarchical Partitioning Public-Domain Software: Implications in Environmental Management and Conservation

PubMed Central

Olea, Pedro P.; Mateo-Tomás, Patricia; de Frutos, Ángel

2010-01-01

Background Hierarchical partitioning (HP) is an analytical method of multiple regression that identifies the most likely causal factors while alleviating multicollinearity problems. Its use is increasing in ecology and conservation by its usefulness for complementing multiple regression analysis. A public-domain software “hier.part package” has been developed for running HP in R software. Its authors highlight a “minor rounding error” for hierarchies constructed from >9 variables, however potential bias by using this module has not yet been examined. Knowing this bias is pivotal because, for example, the ranking obtained in HP is being used as a criterion for establishing priorities of conservation. Methodology/Principal Findings Using numerical simulations and two real examples, we assessed the robustness of this HP module in relation to the order the variables have in the analysis. Results indicated a considerable effect of the variable order on the amount of independent variance explained by predictors for models with >9 explanatory variables. For these models the nominal ranking of importance of the predictors changed with variable order, i.e. predictors declared important by its contribution in explaining the response variable frequently changed to be either most or less important with other variable orders. The probability of changing position of a variable was best explained by the difference in independent explanatory power between that variable and the previous one in the nominal ranking of importance. The lesser is this difference, the more likely is the change of position. Conclusions/Significance HP should be applied with caution when more than 9 explanatory variables are used to know ranking of covariate importance. The explained variance is not a useful parameter to use in models with more than 9 independent variables. The inconsistency in the results obtained by HP should be considered in future studies as well as in those already published. Some recommendations to improve the analysis with this HP module are given. PMID:20657734

Mapping the Structure of Knowledge for Teaching Nominal Categorical Data Analysis

ERIC Educational Resources Information Center

Groth, Randall E.; Bergner, Jennifer A.

2013-01-01

This report describes a model for mapping cognitive structures related to content knowledge for teaching. The model consists of knowledge elements pertinent to teaching a content domain, the nature of the connections among them, and a means for representing the elements and connections visually. The model is illustrated through empirical data…

Concentration and Diversity of Availability and Use in Information Systems: A Positive Reinforcement Model.

ERIC Educational Resources Information Center

Rousseau, Ronald

1992-01-01

Proposes a mathematical model to explain the observed concentration or diversity of nominal classes in information retrieval systems. The Lorenz Curve is discussed, Information Production Process (IPP) is explained, and a heuristic explanation of circumstances in which the model might be used is offered. (30 references) (LRW)

A Simple Treatment of the Liquidity Trap for Intermediate Macroeconomics Courses

ERIC Educational Resources Information Center

Buttet, Sebastien; Roy, Udayan

2014-01-01

Several leading undergraduate intermediate macroeconomics textbooks now include a simple reduced-form New Keynesian model of short-run dynamics (alongside the IS-LM model). Unfortunately, there is no accompanying description of how the zero lower bound on nominal interest rates affects the model. In this article, the authors show how the…

Robust high-performance control for robotic manipulators

NASA Technical Reports Server (NTRS)

Seraji, Homayoun (Inventor)

1991-01-01

Model-based and performance-based control techniques are combined for an electrical robotic control system. Thus, two distinct and separate design philosophies have been merged into a single control system having a control law formulation including two distinct and separate components, each of which yields a respective signal component that is combined into a total command signal for the system. Those two separate system components include a feedforward controller and a feedback controller. The feedforward controller is model-based and contains any known part of the manipulator dynamics that can be used for on-line control to produce a nominal feedforward component of the system's control signal. The feedback controller is performance-based and consists of a simple adaptive PID controller which generates an adaptive control signal to complement the nominal feedforward signal.

High speed propeller performance and noise predictions at takeoff/landing conditions

NASA Technical Reports Server (NTRS)

Nallasamy, M.; Woodward, R. P.; Groeneweg, J. F.

1988-01-01

The performance and noise of a high speed SR-7A model propeller under takeoff/landing conditions are considered. The blade loading distributions are obtained by solving the three-dimensional Euler equations and the sound pressure levels are computed using a time domain approach. At the nominal takeoff operating point, the blade sections near the hub are lightly or negatively loaded. The chordwise loading distributions are distinctly different from those of cruise conditions. The noise of the SR-7A model propeller at takeoff is dominated by the loading noise, similar to that at cruise conditions. The waveforms of the acoustic pressure signature are nearly sinusoidal in the plane of the propeller. The computed directivity of the blade passing frequency tone agrees fairly well with the data at nominal takeoff blade angle.

High speed propeller performance and noise predictions at takeoff/landing conditions

NASA Technical Reports Server (NTRS)

Nallasamy, M.; Woodward, R. P.; Groeneweg, J. F.

1987-01-01

The performance and noise of a high speed SR-7A model propeller under takeoff/landing conditions are considered. The blade loading distributions are obtained by solving the three-dimensional Euler equations and the sound pressure levels are computed using a time domain approach. At the nominal takeoff operating point, the blade sections near the hub are lightly or negatively loaded. The chordwise loading distributions are distinctly different from those of cruise conditions. The noise of the SR-7A model propeller at takeoff is dominated by the loading noise, similar to that at cruise conditions. The waveforms of the acoustic pressure signature are nearly sinusoidal in the plane of the propeller. The computed directivity of the blade passing frequency tone agrees fairly well with the data at nominal takeoff blade angle.

Heat transfer rate distributions on McDonnell-Douglas booster determined by phase change technique for nominal Mach number of 8

NASA Technical Reports Server (NTRS)

Matthews, R. K.; Martindale, W. R.; Warmbrod, J. D.

1972-01-01

The results of a wind tunnel test program to determine aerodynamic heat transfer distributions on the McDonnell Douglas Booster configuration are presented. Heat-transfer rates were determined by the phase-change paint technique on 0.009-scale Stycast models using Tempilaq as the surface temperature indicator. The nominal test conditions were; Mach 8, length Reynolds numbers 5 million and 7.3 million, and angles of attack of 40, 50, and 60 deg. At the higher Reynolds number, data were obtained with and without boundary layer trips. Model details, test conditions, and reduced heat-transfer data are presented. Data reduction of the phase-change paint photographs was performed by utilizing a new technique which is described.

Inductive System Health Monitoring

NASA Technical Reports Server (NTRS)

Iverson, David L.

2004-01-01

The Inductive Monitoring System (IMS) software was developed to provide a technique to automatically produce health monitoring knowledge bases for systems that are either difficult to model (simulate) with a computer or which require computer models that are too complex to use for real time monitoring. IMS uses nominal data sets collected either directly from the system or from simulations to build a knowledge base that can be used to detect anomalous behavior in the system. Machine learning and data mining techniques are used to characterize typical system behavior by extracting general classes of nominal data from archived data sets. IMS is able to monitor the system by comparing real time operational data with these classes. We present a description of learning and monitoring method used by IMS and summarize some recent IMS results.

75 FR 43933 - Request for nominations for members to serve on National Institute of Standards and Technology...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-27

... duties. Selection of ISPAB members will not be limited to individuals who are nominated. Nominations that.... Selection of MEP Advisory Board members will not be limited to individuals who are nominated. Nominations... in its official role as the private sector policy advisor of the Institute is concerned. Each such...

77 FR 40332 - Request for Nominations for Members To Serve on National Institute of Standards and Technology...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-09

... duties. Selection of ISPAB members will not be limited to individuals who are nominated. Nominations that... to individuals who are nominated. Nominations that are received and meet the requirements will be... policy advisor of NIST is concerned. Each such report shall identify areas of program emphasis for NIST...

78 FR 67121 - Request for Nominations for Members To Serve on National Institute of Standards and Technology...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-08

... to individuals who are nominated. Nominations that are received and meet the requirements will be.... Selection of MEP Advisory Board members will not be limited to individuals who are nominated. Nominations... official role as the private sector policy adviser of NIST is concerned. Each such report shall identify...

Space shuttle orbiter rear mounted reaction control system jet interaction study. [hypersonic wind tunnel tests

NASA Technical Reports Server (NTRS)

Rausch, J. R.

1977-01-01

The effect of interaction between the reaction control system (RCS) jets and the flow over the space shuttle orbiter in the atmosphere was investigated in the NASA Langley 31-inch continuous flow hypersonic tunnel at a nominal Mach number of 10.3 and in the AEDC continuous flow hypersonic tunnel B at a nominal Mach number of 6, using 0.01 and .0125 scale force models with aft RCS nozzles mounted both on the model and on the sting of the force model balance. The data show that RCS nozzle exit momentum ratio is the primary correlating parameter for effects where the plume impinges on an adjacent surface and mass flow ratio is the parameter when the plume interaction is primarily with the external stream. An analytic model of aft mounted RCS units was developed in which the total reaction control moments are the sum of thrust, impingement, interaction, and cross-coupling terms.

Ares I-X Flight Test Validation of Control Design Tools in the Frequency-Domain

NASA Technical Reports Server (NTRS)

Johnson, Matthew; Hannan, Mike; Brandon, Jay; Derry, Stephen

2011-01-01

A major motivation of the Ares I-X flight test program was to Design for Data, in order to maximize the usefulness of the data recorded in support of Ares I modeling and validation of design and analysis tools. The Design for Data effort was intended to enable good post-flight characterizations of the flight control system, the vehicle structural dynamics, and also the aerodynamic characteristics of the vehicle. To extract the necessary data from the system during flight, a set of small predetermined Programmed Test Inputs (PTIs) was injected directly into the TVC signal. These PTIs were designed to excite the necessary vehicle dynamics while exhibiting a minimal impact on loads. The method is similar to common approaches in aircraft flight test programs, but with unique launch vehicle challenges due to rapidly changing states, short duration of flight, a tight flight envelope, and an inability to repeat any test. This paper documents the validation effort of the stability analysis tools to the flight data which was performed by comparing the post-flight calculated frequency response of the vehicle to the frequency response calculated by the stability analysis tools used to design and analyze the preflight models during the control design effort. The comparison between flight day frequency response and stability tool analysis for flight of the simulated vehicle shows good agreement and provides a high level of confidence in the stability analysis tools for use in any future program. This is true for both a nominal model as well as for dispersed analysis, which shows that the flight day frequency response is enveloped by the vehicle s preflight uncertainty models.

An experimental and computational investigation of film cooling effects on an interceptor forebody at Mach 10

NASA Astrophysics Data System (ADS)

Majeski, J. A.; Morris, H. W.

1990-01-01

An experiment using a full-scale model of an interceptor forebody configuration was conducted to determine the effectiveness of transpiration and film cooling on temperature control of an IR window during hypersonic flight. This experiment was conducted at a freestream Mach number of 10. The test total temperature was nominally 1100 K, and the test total pressure was nominally 50,000 KPa. The Reynolds number associated with these test conditions was 34.1 million/m. Results encompass pressure data, heat-transfer data, effect of upstream transpiration cooling, and film cooling effectiveness.

Detection and visualization of storm hydrograph changes under urbanization: an impulse response approach.

PubMed

Farahmand, Touraj; Fleming, Sean W; Quilty, Edward J

2007-10-01

Urbanization often alters catchment storm responses, with a broad range of potentially significant environmental and engineering consequences. At a practical, site-specific management level, efficient and effective assessment and control of such downstream impacts requires a technical capability to rapidly identify development-induced storm hydrograph changes. The method should also speak specifically to alteration of internal watershed dynamics, require few resources to implement, and provide results that are intuitively accessible to all watershed stakeholders. In this short paper, we propose a potential method which might satisfy these criteria. Our emphasis lies upon the integration of existing concepts to provide tools for pragmatic, relatively low-cost environmental monitoring and management. The procedure involves calibration of rainfall-runoff time-series models in each of several successive time windows, which sample varying degrees of watershed urbanization. As implemented here, only precipitation and stream discharge or stage data are required. The readily generated unit impulse response functions of these time-series models might then provide a mathematically formal, yet visually based and intuitive, representation of changes in watershed storm response. Nominally, the empirical response functions capture such changes as soon as they occur, and the assessments of storm hydrograph alteration are independent of variability in meteorological forcing. We provide a preliminary example of how the technique may be applied using a low-order linear ARX model. The technique may offer a fresh perspective on such watershed management issues, and potentially also several advantages over existing approaches. Substantial further testing is required before attempting to apply the concept as a practical environmental management technique; some possible directions for additional work are suggested.

76 FR 39379 - Request for Nominations for Members To Serve on National Institute of Standards and Technology...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-06

... will not be limited to individuals who are nominated. Nominations that are received and meet the... individuals who are nominated. Nominations that are received and meet the requirements will be kept on file to... in its official role as the private sector policy advisor of the Institute is concerned. Each such...

Using Sdo's AIA to Investigate Energy Transport from a Flare's Energy Release Site to the Chromosphere

NASA Technical Reports Server (NTRS)

Brosius, Jeffrey W.; Holman, Gordon D.

2012-01-01

Coordinated observations of a GOES B4.8 microflare with SDOs Atmospheric Imaging Assembly (AIA) and the RamatyHigh Energy Solar Spectroscopic Imager (RHESSI) on 2010 July 31 show that emission in all seven of AIAs EUV channels brightened simultaneously nearly 6 min before RHESSI or GOES detected emission from plasma at temperatures around 10 MK. Aims. To help interpret these and AIA flare observations in general, we characterized the expected temporal responses of AIAs 94, 131, 171, 193, 211, and 335 channels to solar flare brightenings by combining (1) AIAs nominal temperature response functions available through SSWIDL with (2) EUV spectral line data observed in a flare loop Coordinated observations of a GOES B4.8 microflare with SDOs Atmospheric Imaging Assembly (AIA) and the RamatyHigh Energy Solar Spectroscopic Imager (RHESSI) on 2010 July 31 show that emission in all seven of AIAs EUV channels brightenedsimultaneously nearly 6 min before RHESSI or GOES detected emission from plasma at temperatures around 10 MK.Aims. To help interpret these and AIA flare observations in general, we characterized the expected temporal responses of AIAs 94,131, 171, 193, 211, and 335 channels to solar flare brightenings by combining (1) AIAs nominal temperature response functionsavailable through SSWIDL with (2) EUV spectral line data observed in a flare loop

The Effect of Small Sample Size on Measurement Equivalence of Psychometric Questionnaires in MIMIC Model: A Simulation Study.

PubMed

Jamali, Jamshid; Ayatollahi, Seyyed Mohammad Taghi; Jafari, Peyman

2017-01-01

Evaluating measurement equivalence (also known as differential item functioning (DIF)) is an important part of the process of validating psychometric questionnaires. This study aimed at evaluating the multiple indicators multiple causes (MIMIC) model for DIF detection when latent construct distribution is nonnormal and the focal group sample size is small. In this simulation-based study, Type I error rates and power of MIMIC model for detecting uniform-DIF were investigated under different combinations of reference to focal group sample size ratio, magnitude of the uniform-DIF effect, scale length, the number of response categories, and latent trait distribution. Moderate and high skewness in the latent trait distribution led to a decrease of 0.33% and 0.47% power of MIMIC model for detecting uniform-DIF, respectively. The findings indicated that, by increasing the scale length, the number of response categories and magnitude DIF improved the power of MIMIC model, by 3.47%, 4.83%, and 20.35%, respectively; it also decreased Type I error of MIMIC approach by 2.81%, 5.66%, and 0.04%, respectively. This study revealed that power of MIMIC model was at an acceptable level when latent trait distributions were skewed. However, empirical Type I error rate was slightly greater than nominal significance level. Consequently, the MIMIC was recommended for detection of uniform-DIF when latent construct distribution is nonnormal and the focal group sample size is small.

The Effect of Small Sample Size on Measurement Equivalence of Psychometric Questionnaires in MIMIC Model: A Simulation Study

PubMed Central

Jafari, Peyman

2017-01-01

Evaluating measurement equivalence (also known as differential item functioning (DIF)) is an important part of the process of validating psychometric questionnaires. This study aimed at evaluating the multiple indicators multiple causes (MIMIC) model for DIF detection when latent construct distribution is nonnormal and the focal group sample size is small. In this simulation-based study, Type I error rates and power of MIMIC model for detecting uniform-DIF were investigated under different combinations of reference to focal group sample size ratio, magnitude of the uniform-DIF effect, scale length, the number of response categories, and latent trait distribution. Moderate and high skewness in the latent trait distribution led to a decrease of 0.33% and 0.47% power of MIMIC model for detecting uniform-DIF, respectively. The findings indicated that, by increasing the scale length, the number of response categories and magnitude DIF improved the power of MIMIC model, by 3.47%, 4.83%, and 20.35%, respectively; it also decreased Type I error of MIMIC approach by 2.81%, 5.66%, and 0.04%, respectively. This study revealed that power of MIMIC model was at an acceptable level when latent trait distributions were skewed. However, empirical Type I error rate was slightly greater than nominal significance level. Consequently, the MIMIC was recommended for detection of uniform-DIF when latent construct distribution is nonnormal and the focal group sample size is small. PMID:28713828

Systems identification and application systems development for monitoring the physiological and health status of crewmen in space

NASA Technical Reports Server (NTRS)

Leonard, J. I.; Furukawa, S.; Vannordstrand, P. C.

1975-01-01

The use of automated, analytical techniques to aid medical support teams is suggested. Recommendations are presented for characterizing crew health in terms of: (1) wholebody function including physiological, psychological and performance factors; (2) a combination of critical performance indexes which consist of multiple factors of measurable parameters; (3) specific responses to low noise level stress tests; and (4) probabilities of future performance based on present and periodic examination of past performance. A concept is proposed for a computerized real time biomedical monitoring and health care system that would have the capability to integrate monitored data, detect off-nominal conditions based on current knowledge of spaceflight responses, predict future health status, and assist in diagnosis and alternative therapies. Mathematical models could play an important role in this approach, especially when operating in a real time mode. Recommendations are presented to update the present health monitoring systems in terms of recent advances in computer technology and biomedical monitoring systems.

The Total Synthesis Problem of linear multivariable control. II - Unity feedback and the design morphism

NASA Technical Reports Server (NTRS)

Sain, M. K.; Antsaklis, P. J.; Gejji, R. R.; Wyman, B. F.; Peczkowski, J. L.

1981-01-01

Zames (1981) has observed that there is, in general, no 'separation principle' to guarantee optimality of a division between control law design and filtering of plant uncertainty. Peczkowski and Sain (1978) have solved a model matching problem using transfer functions. Taking into consideration this investigation, Peczkowski et al. (1979) proposed the Total Synthesis Problem (TSP), wherein both the command/output-response and command/control-response are to be synthesized, subject to the plant constraint. The TSP concept can be subdivided into a Nominal Design Problem (NDP), which is not dependent upon specific controller structures, and a Feedback Synthesis Problem (FSP), which is. Gejji (1980) found that NDP was characterized in terms of the plant structural matrices and a single, 'good' transfer function matrix. Sain et al. (1981) have extended this NDP work. The present investigation is concerned with a study of FSP for the unity feedback case. NDP, together with feedback synthesis, is understood as a Total Synthesis Problem.

SeaWiFS Technical Report Series. Volume 40; SeaWiFS Calibration Topics

NASA Technical Reports Server (NTRS)

Barnes, Robert A.; Eplee, Robert E., Jr.; Yeh, Eueng-nan; Esaias, Wayne E.

1997-01-01

For Earth-observing satellite instruments, it was standard to consider each instrument band to have a spectral response that is infinitely narrow, i.e., to have a response from a single wavelength. The SeaWiFS bands, however, have nominal spectral bandwidths of 20 and 40 nm. These bandwidths effect the SeaWiFS measurements on orbit. The effects are also linked to the manner in which the instrument was calibrated and to the spectral shape of the radiance that SeaWiFS views. The spectral shape of that radiance will not be well known on orbit. In this technical memorandum, two source spectra are examined. The first is a 12,000 K Planck function, and the second is based on the modeling results of H. Gordon at the University of Miami. By comparing these spectra, the best available corrections to the SeaWiFS measurements for source spectral shape, plus estimates of the uncertainties in these corrections, can be tabulated.

Adaptive Critic-based Neurofuzzy Controller for the Steam Generator Water Level

NASA Astrophysics Data System (ADS)

Fakhrazari, Amin; Boroushaki, Mehrdad

2008-06-01

In this paper, an adaptive critic-based neurofuzzy controller is presented for water level regulation of nuclear steam generators. The problem has been of great concern for many years as the steam generator is a highly nonlinear system showing inverse response dynamics especially at low operating power levels. Fuzzy critic-based learning is a reinforcement learning method based on dynamic programming. The only information available for the critic agent is the system feedback which is interpreted as the last action the controller has performed in the previous state. The signal produced by the critic agent is used alongside the backpropagation of error algorithm to tune online conclusion parts of the fuzzy inference rules. The critic agent here has a proportional-derivative structure and the fuzzy rule base has nine rules. The proposed controller shows satisfactory transient responses, disturbance rejection and robustness to model uncertainty. Its simple design procedure and structure, nominates it as one of the suitable controller designs for the steam generator water level control in nuclear power plant industry.

10 CFR 431.36 - Compliance Certification.

Code of Federal Regulations, 2010 CFR

2010-01-01

... EQUIPMENT Electric Motors Certification § 431.36 Compliance Certification. (a) General. Beginning April 26, 2003, a manufacturer or private labeler shall not distribute in commerce any basic model of an electric...: (i) The nominal full load efficiency for each basic model of electric motor distributed is not less...

75 FR 22790 - Science Advisory Board Staff Office; Request for Nominations of Candidates for EPA's Advisory...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-30

... modeling; atmospheric science and engineering; ecology and ecological risk assessment; epidemiology... assessment; environmental modeling; industrial ecology; environmental engineering; environmental medicine... ``Ethics Requirements for Advisors'' link on the blue navigational bar on the SAB Web site at http://www...

10 CFR 431.36 - Compliance Certification.

Code of Federal Regulations, 2012 CFR

2012-01-01

... EQUIPMENT Electric Motors Certification § 431.36 Compliance Certification. (a) General. Beginning April 26, 2003, a manufacturer or private labeler shall not distribute in commerce any basic model of an electric...: (i) The nominal full load efficiency for each basic model of electric motor distributed is not less...

Conceptual and linguistic representations of kinds and classes

PubMed Central

Prasada, Sandeep; Hennefield, Laura; Otap, Daniel

2013-01-01

We investigate the hypothesis that our conceptual systems provide two formally distinct ways of representing categories by investigating the manner in which lexical nominals (e.g., tree, picnic table) and phrasal nominals (e.g., black bird, birds that like rice) are interpreted. Four experiments found that lexical nominals may be mapped onto kind representations whereas phrasal nominals map onto class representations but not kind representations. Experiment 1 found that phrasal nominals, unlike lexical nominals, are mapped onto categories whose members need not be of a single kind. Experiments 2 and 3 found that categories named by lexical nominals enter into both class inclusion and kind hierarchies and thus support both class inclusion (is a) and kind specification (kind of) relations, whereas phrasal nominals map onto class representations which support only class inclusion relations. Experiment 4 showed that the two types of nominals represent hierarchical relations in different ways. Phrasal nominals (e.g., white bear) are mapped onto classes that have criteria of membership in addition to those specified by the class picked out by the head noun of the phrase (e.g., bear). In contrast, lexical nominals (e.g., polar bear) specify one way to meet the criteria specified by the more general kind concept (e.g., bear). Implications for the language-conceptual system interface, representation of hierarchical relations, lexicalization, and theories of conceptual combination are discussed. PMID:22671567

Grounding by Attention Simulation in Peripersonal Space: Pupils Dilate to Pinch Grip But Not Big Size Nominal Classifier.

PubMed

Lobben, Marit; Bochynska, Agata

2018-03-01

Grammatical categories represent implicit knowledge, and it is not known if such abstract linguistic knowledge can be continuously grounded in real-life experiences, nor is it known what types of mental states can be simulated. A former study showed that attention bias in peripersonal space (PPS) affects reaction times in grammatical congruency judgments of nominal classifiers, suggesting that simulated semantics may include reenactment of attention. In this study, we contrasted a Chinese nominal classifier used with nouns denoting pinch grip objects with a classifier for nouns with big object referents in a pupil dilation experiment. Twenty Chinese native speakers read grammatical and ungrammatical classifier-noun combinations and made grammaticality judgment while their pupillary responses were measured. It was found that their pupils dilated significantly more to the pinch grip classifier than to the big object classifier, indicating attention simulation in PPS. Pupil dilations were also significantly larger with congruent trials on the whole than in incongruent trials, but crucially, congruency and classifier semantics were independent of each other. No such effects were found in controls. Copyright © 2017 Cognitive Science Society, Inc.

7 CFR 917.18 - Nomination of commodity committee members of the Control Committee.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Administrative Bodies § 917.18 Nomination of commodity committee members of the Control Committee. Nominations... committee shall be entitled to nominate shall be based upon the proportion that the previous three fiscal...

7 CFR 917.18 - Nomination of commodity committee members of the Control Committee.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Administrative Bodies § 917.18 Nomination of commodity committee members of the Control Committee. Nominations... committee shall be entitled to nominate shall be based upon the proportion that the previous three fiscal...

7 CFR 917.18 - Nomination of commodity committee members of the Control Committee.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Administrative Bodies § 917.18 Nomination of commodity committee members of the Control Committee. Nominations... committee shall be entitled to nominate shall be based upon the proportion that the previous three fiscal...

7 CFR 917.18 - Nomination of commodity committee members of the Control Committee.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Administrative Bodies § 917.18 Nomination of commodity committee members of the Control Committee. Nominations... committee shall be entitled to nominate shall be based upon the proportion that the previous three fiscal...

7 CFR 917.18 - Nomination of commodity committee members of the Control Committee.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Administrative Bodies § 917.18 Nomination of commodity committee members of the Control Committee. Nominations... committee shall be entitled to nominate shall be based upon the proportion that the previous three fiscal...

Potential limitations of NRC in predicting energetic requirements of beef females within western U.S. grazing systems

USDA-ARS?s Scientific Manuscript database

Assessment of beef cow energy balance and efficiency in grazing-extensive rangelands has occurred on a nominal basis over short time intervals and has not accounted for the complexity of metabolic and digestive responses; behavioral adaptations to climatic, terrain, and vegetation variables; and doc...

40 CFR 86.1314-94 - Analytical gases.

Code of Federal Regulations, 2010 CFR

2010-07-01

... CO2. respectively, using nitrogen as the diluent. (b) Gases for the hydrocarbon analyzer shall be: (1... named as NOX with a maximum NO2 concentration of five percent of the nominal value using nitrogen as the... the balance being helium. The mixture shall contain less than 1 ppm equivalent carbon response. 98 to...

40 CFR 86.1314-94 - Analytical gases.

Code of Federal Regulations, 2012 CFR

2012-07-01

... CO2. respectively, using nitrogen as the diluent. (b) Gases for the hydrocarbon analyzer shall be: (1... named as NOX with a maximum NO2 concentration of five percent of the nominal value using nitrogen as the... the balance being helium. The mixture shall contain less than 1 ppm equivalent carbon response. 98 to...

40 CFR 86.1314-94 - Analytical gases.

Code of Federal Regulations, 2013 CFR

2013-07-01

... CO2. respectively, using nitrogen as the diluent. (b) Gases for the hydrocarbon analyzer shall be: (1... named as NOX with a maximum NO2 concentration of five percent of the nominal value using nitrogen as the... the balance being helium. The mixture shall contain less than 1 ppm equivalent carbon response. 98 to...

40 CFR 86.1314-94 - Analytical gases.

Code of Federal Regulations, 2011 CFR

2011-07-01

... CO2. respectively, using nitrogen as the diluent. (b) Gases for the hydrocarbon analyzer shall be: (1... named as NOX with a maximum NO2 concentration of five percent of the nominal value using nitrogen as the... the balance being helium. The mixture shall contain less than 1 ppm equivalent carbon response. 98 to...

30 CFR 285.213 - What must I submit in response to a Request for Interest or a Call for Information and Nominations?

Code of Federal Regulations, 2010 CFR

2010-07-01

... MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE ENERGY ALTERNATE USES OF EXISTING FACILITIES ON THE OUTER CONTINENTAL SHELF Issuance of OCS Renewable Energy Leases Competitive Lease Process... and pertinent data and information concerning renewable energy and environmental conditions in the...

30 CFR 585.213 - What must I submit in response to a Request for Interest or a Call for Information and Nominations?

Code of Federal Regulations, 2012 CFR

2012-07-01

... OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE ENERGY AND ALTERNATE USES OF EXISTING FACILITIES ON THE OUTER CONTINENTAL SHELF Issuance of OCS Renewable Energy Leases Competitive.... (d) Available and pertinent data and information concerning renewable energy and environmental...

30 CFR 585.213 - What must I submit in response to a Request for Interest or a Call for Information and Nominations?

Code of Federal Regulations, 2013 CFR

2013-07-01

... OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE ENERGY AND ALTERNATE USES OF EXISTING FACILITIES ON THE OUTER CONTINENTAL SHELF Issuance of OCS Renewable Energy Leases Competitive.... (d) Available and pertinent data and information concerning renewable energy and environmental...

30 CFR 585.213 - What must I submit in response to a Request for Interest or a Call for Information and Nominations?

Code of Federal Regulations, 2014 CFR

2014-07-01

... OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE ENERGY AND ALTERNATE USES OF EXISTING FACILITIES ON THE OUTER CONTINENTAL SHELF Issuance of OCS Renewable Energy Leases Competitive.... (d) Available and pertinent data and information concerning renewable energy and environmental...

Introduction to Latent Class Analysis with Applications

ERIC Educational Resources Information Center

Porcu, Mariano; Giambona, Francesca

2017-01-01

Latent class analysis (LCA) is a statistical method used to group individuals (cases, units) into classes (categories) of an unobserved (latent) variable on the basis of the responses made on a set of nominal, ordinal, or continuous observed variables. In this article, we introduce LCA in order to demonstrate its usefulness to early adolescence…

Case Studies of Self-Actualization.

ERIC Educational Resources Information Center

Brennan, Thomas P.; Piechowski, Michael M.

Case studies of self-actualizing people according to the ideas of A. Maslow and the criteria of K. Dabrowski are presented. To find people meeting the criteria of Level 4 of the Dabrowski theory, a pool of 21 subjects was established by nomination. All subjects were given the Definition-Response Instrument to assess levels of emotional…

76 FR 18826 - Unified Carrier Registration Plan Board of Directors; Request for Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-05

... four members from such State agencies, one from each of FMCSA's four service areas. As authorized by 49... 20590. Office hours are between 9 a.m. and 5 p.m., ET, Monday through Friday, except Federal holidays..., Federal, and industry representatives responsible for developing, implementing, and administering the UCRA...

Unlocking Potential: How Political Skill Can Maximize Superintendent Effectiveness

ERIC Educational Resources Information Center

Hill, Paul; Jochim, Ashley

2018-01-01

Local superintendents must do an important job while equipped with, at best, modest authority. Superintendents are ultimately responsible for all the schools in their district, and they at least nominally supervise everything that happens in those schools. Yet superintendents cannot count on obedience or even support from the people who work for…

75 FR 9459 - Self-Regulatory Organizations; Financial Industry Regulatory Authority, Inc.; Notice of Filing of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-02

... transfer such committees' responsibilities for NAC industry appointments to the FINRA Nominating Committee... entities by telegraph, telefax, cable, radio, wireless or other device or method. FINRA intends ``other... members. In addition, any committee of the board that is delegated any power and authority of the board...

69 Good Ideas: Responses to Changing Educational Needs by State Colleges and Universities.

ERIC Educational Resources Information Center

Costello, Libby, Comp.

A collection of program ideas are presented that were nominated by their institutions in the 1983 competition for the American Association of State Colleges and Universities' G. Theodore Mitau Award for Innovation and Change in Higher Education. The programs demonstrate creative approaches to such academic/administrative concerns as student access…

Large Second-Harmonic Response of C60 Thin Films

DTIC Science & Technology

1992-04-01

temperature; the largest value occurred at a nominal temperature of 140’C where X"’ is ten times larger than the room temperature value. 14. SU8 )ECT TERMS 1S...optical chromatography.’ The purity was examined by Raman. IR materials based upon conjugated-carbon- polymers charac- absorption, high-performance liquid

Guide to major programs and activities

NASA Astrophysics Data System (ADS)

LEADERSHIP: The AGU Council of elected Union and Section officers has full responsibility for AGU affairs AGU Council: Ralph Cicerone (President), Fred Spilhaus; Review Union Statutes and Bylaws: John R. Ritter, Fred Spilhaus; Develop a strategic plan for the Union Planning: Marcia Neugebauer; Fred Spilhaus; ELECTIONS: Propose candidates for Union offices Nominations: Don L. Anderson, Fred Spilhaus.

76 FR 77038 - Self-Regulatory Organizations; Stock Clearing Corporation of Philadelphia; Order Approving...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-09

.... Second, NASDAQ OMX is proposing to amend the compositional requirements of the Nominating & Governance... approve a proposed rule change of a self-regulatory organization if it finds that such proposed rule... are in the custody or control of such clearing agency or for which it is responsible, and to comply...

76 FR 77048 - Self-Regulatory Organizations; Boston Stock Exchange Clearing Corporation; Order Approving...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-09

.... Second, NASDAQ OMX is proposing to amend the compositional requirements of the Nominating & Governance... approve a proposed rule change of a self-regulatory organization if it finds that such proposed rule... are in the custody or control of such clearing agency or for which it is responsible, and to comply...

Bullying Perpetration and Victimization in Early Adolescence: Physiological Response to Social Exclusion

ERIC Educational Resources Information Center

Mazzone, Angela; Camodeca, Marina; Cardone, Daniela; Merla, Arcangelo

2017-01-01

The present study investigated the associations between bullying perpetration and victimization and physiological reactivity to social exclusion. The participants were 28 early adolescents (17 boys and 11 girls; M[subscript age] = 11.55; SD = 1.34). Bullying perpetration and victimization were assessed by peer nominations. To elicit social…

Understanding American-Indian children’s perceived barriers and facilitators to following the Dietary Guidelines for Americans (DGA)

USDA-ARS?s Scientific Manuscript database

Ninety-two American Indian 5th graders from a rural, northern plains reservation community completed Nominal Group Technique (NGT) sessions designed to understand both barriers and facilitators to following DGA. Individually and in small groups, children generated lists of responses to specific que...

EFFECTS OF EUTROPHICATION ON VITELLOGENIN GENE EXPRESSION IN MALE FATHEAD MINNOWS (PIMEPHALES PROMELAS) EXPOSED TO 17A-ETHYNYLESTRADIOL IN FIELD MESOCOSMS

EPA Science Inventory

This study evaluated the effect of aquatic secondary nutrient supply levels (nitrogen and phosphorus) on the subcellular response of adult male fathead minnows (Pimephales promelas) exposed to a single nominal concentration of 17a-ethynylestradiol (EE2), a potent synthetic estrog...

Nonlinear optical response of nanocomposites based on KDP single crystal with incorporated Al2O3*nH2O nanofibriles under CW and pulsed laser irradiation at 532 nm

NASA Astrophysics Data System (ADS)

Popov, A. S.; Uklein, A. V.; Multian, V. V.; Dantec, R. Le; Kostenyukova, E. I.; Bezkrovnaya, O. N.; Pritula, I. M.; Gayvoronsky, V. Ya.

2016-11-01

Optical properties and nonlinear optical response due to the CW and pulsed laser radiation self-action at 532 nm were studied in composites based on KDP single crystals with incorporated nanofibriles of nanostructured oxyhydroxide of aluminum (NOA). It was shown a high optical quality and structural homogeneity of nanocomposites KDP:NOA by the transmittance spectra, elastic optical scattering and XRD analysis. It was observed manifestation of the second harmonic generation efficiency enhancement in the KDP:NOA versus the nominally pure KDP (λ=1064 nm, τ=1 ns) that is correlated with efficient refractive index self-modulation Δn ∼10-4 (λ=532 nm, τ=30 ps). In the pyramidal and prismatic growth sectors of the nominally pure KDP crystal it was shown opposite signs of the photoinduced variations both of the refractive index and of the optical absorption/bleaching due to resonant excitation of the native defects at 532 nm. It should be considered for the wide-aperture laser frequency KDP family based convertors fabrication.

MCNP6 simulation of radiographs generated from megaelectron volt X-rays for characterizing a computed tomography system

NASA Astrophysics Data System (ADS)

Dooraghi, Alex A.; Tringe, Joseph W.

2018-04-01

To evaluate conventional munition, we simulated an x-ray computed tomography (CT) system for generating radiographs from nominal x-ray energies of 6 or 9 megaelectron volts (MeV). CT simulations, informed by measured data, allow for optimization of both system design and acquisition techniques necessary to enhance image quality. MCNP6 radiographic simulation tools were used to model ideal detector responses (DR) that assume either (1) a detector response proportional to photon flux (N) or (2) a detector response proportional to energy flux (E). As scatter may become significant with MeV x-ray systems, simulations were performed with and without the inclusion of object scatter. Simulations were compared against measurements of a cylindrical munition component principally composed of HMX, tungsten and aluminum encased in carbon fiber. Simulations and measurements used a 6 MeV peak energy x-ray spectrum filtered with 3.175 mm of tantalum. A detector response proportional to energy which includes object scatter agrees to within 0.6 % of the measured line integral of the linear attenuation coefficient. Exclusion of scatter increases the difference between measurement and simulation to 5 %. A detector response proportional to photon flux agrees to within 20 % when object scatter is included in the simulation and 27 % when object scatter is excluded.

44 CFR 150.3 - Nomination process.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Section 150.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... Nomination process. (a) The Nominating Officials nominating Firefighters and Civil Defense Officers shall...) Civil defense officer (or member of a recognized civil defense or emergency preparedness organization...

44 CFR 150.3 - Nomination process.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Section 150.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... Nomination process. (a) The Nominating Officials nominating Firefighters and Civil Defense Officers shall...) Civil defense officer (or member of a recognized civil defense or emergency preparedness organization...

44 CFR 150.3 - Nomination process.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Section 150.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... Nomination process. (a) The Nominating Officials nominating Firefighters and Civil Defense Officers shall...) Civil defense officer (or member of a recognized civil defense or emergency preparedness organization...

44 CFR 150.3 - Nomination process.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Section 150.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... Nomination process. (a) The Nominating Officials nominating Firefighters and Civil Defense Officers shall...) Civil defense officer (or member of a recognized civil defense or emergency preparedness organization...

44 CFR 150.3 - Nomination process.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Section 150.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... Nomination process. (a) The Nominating Officials nominating Firefighters and Civil Defense Officers shall...) Civil defense officer (or member of a recognized civil defense or emergency preparedness organization...

77 FR 19056 - Information Reporting Program Advisory Committee (IRPAC); Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-29

... DEPARTMENT OF TREASURY Internal Revenue Service Information Reporting Program Advisory Committee (IRPAC); Nominations AGENCY: Internal Revenue Service, Department of Treasury. ACTION: Request for Nominations. SUMMARY: The Internal Revenue Service (IRS) requests nominations of individuals for selection to...

78 FR 19582 - Information Reporting Program Advisory Committee (IRPAC); Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-01

... DEPARTMENT OF TREASURY Internal Revenue Service Information Reporting Program Advisory Committee (IRPAC); Nominations AGENCY: Internal Revenue Service, Department of Treasury. ACTION: Request for Nominations. SUMMARY: The Internal Revenue Service (IRS) requests nominations of individuals for selection to...

Stability analysis of an F/A-18 E/F cable mount m odel

NASA Technical Reports Server (NTRS)

Thompson, Nancy; Farmer, Moses

1994-01-01

A full-span F/A-18 E/F cable mounted wind tunnel model is part of a flutter clearance program at the NASA Langley Transonic Dynamics Tunnel. Parametric analysis of this model using GRUMCBL software was conducted to assess stability for wind tunnel tests. Two configurations of the F/A-18 E/F were examined. The parameters examined were pulley-cable friction, mach number, dynamic pressure, cable geometry, center of gravity location, cable tension, snubbing the model, drag, and test medium. For the nominal cable geometry (Cable Geometry 1), Configuration One was unstable for cases with higher pulley-cable friction coefficients. A new cable geometry (Cable Geometry 3) was determined in which Configuration One was stable for all cases evaluated. Configuration Two with the nominal center of gravity position was found to be unstable for cases with higher pulley-cable friction coefficients; however, the model was stable when the center of gravity moved forward 1/2. The model was tested using the cable mount system during the initial wind tunnel entry and was stable as predicted.

Physical resist models and their calibration: their readiness for accurate EUV lithography simulation

NASA Astrophysics Data System (ADS)

Klostermann, U. K.; Mülders, T.; Schmöller, T.; Lorusso, G. F.; Hendrickx, E.

2010-04-01

In this paper, we discuss the performance of EUV resist models in terms of predictive accuracy, and we assess the readiness of the corresponding model calibration methodology. The study is done on an extensive OPC data set collected at IMEC for the ShinEtsu resist SEVR-59 on the ASML EUV Alpha Demo Tool (ADT), with the data set including more than thousand CD values. We address practical aspects such as the speed of calibration and selection of calibration patterns. The model is calibrated on 12 process window data series varying in pattern width (32, 36, 40 nm), orientation (H, V) and pitch (dense, isolated). The minimum measured feature size at nominal process condition is a 32 nm CD at a dense pitch of 64 nm. Mask metrology is applied to verify and eventually correct nominal width of the drawn CD. Cross-sectional SEM information is included in the calibration to tune the simulated resist loss and sidewall angle. The achieved calibration RMS is ~ 1.0 nm. We show what elements are important to obtain a well calibrated model. We discuss the impact of 3D mask effects on the Bossung tilt. We demonstrate that a correct representation of the flare level during the calibration is important to achieve a high predictability at various flare conditions. Although the model calibration is performed on a limited subset of the measurement data (one dimensional structures only), its accuracy is validated based on a large number of OPC patterns (at nominal dose and focus conditions) not included in the calibration; validation RMS results as small as 1 nm can be reached. Furthermore, we study the model's extendibility to two-dimensional end of line (EOL) structures. Finally, we correlate the experimentally observed fingerprint of the CD uniformity to a model, where EUV tool specific signatures are taken into account.

[Masters of Chilean Internal Medicine].

PubMed

Rosselot, Eduardo

2003-08-01

Master of internal Medicine is the highest award granted by the Chilean Society of Internal Medicine (Sociedad Médica de Santiago) to its members. This article outlines the sense and transcendence of this award and provides an abridged, certainly incomplete, data of the recipients since 1981 when this award was first given. Those who have received it are not the only ones that have the attributes to deserve such distinction. There are many members with similar or even better merits, and therefore the Directory of the Society is usually exposed to a very hard decision when facing each new nomination. When a member is awarded, he becomes a model to be emulated or surpassed by the future generations; thus assumes the great responsibility of maintaining the spirit, the prestige and the projection of Internal Medicine into the future.

Avalanche weak layer shear fracture parameters from the cohesive crack model

NASA Astrophysics Data System (ADS)

McClung, David

2014-05-01

Dry slab avalanches release by mode II shear fracture within thin weak layers under cohesive snow slabs. The important fracture parameters include: nominal shear strength, mode II fracture toughness and mode II fracture energy. Alpine snow is not an elastic material unless the rate of deformation is very high. For natural avalanche release, it would not be possible that the fracture parameters can be considered as from classical fracture mechanics from an elastic framework. The strong rate dependence of alpine snow implies that it is a quasi-brittle material (Bažant et al., 2003) with an important size effect on nominal shear strength. Further, the rate of deformation for release of an avalanche is unknown, so it is not possible to calculate the fracture parameters for avalanche release from any model which requires the effective elastic modulus. The cohesive crack model does not require the modulus to be known to estimate the fracture energy. In this paper, the cohesive crack model was used to calculate the mode II fracture energy as a function of a brittleness number and nominal shear strength values calculated from slab avalanche fracture line data (60 with natural triggers; 191 with a mix of triggers). The brittleness number models the ratio of the approximate peak value of shear strength to nominal shear strength. A high brittleness number (> 10) represents large size relative to fracture process zone (FPZ) size and the implications of LEFM (Linear Elastic Fracture Mechanics). A low brittleness number (e.g. 0.1) represents small sample size and primarily plastic response. An intermediate value (e.g. 5) implies non-linear fracture mechanics with intermediate relative size. The calculations also implied effective values for the modulus and the critical shear fracture toughness as functions of the brittleness number. The results showed that the effective mode II fracture energy may vary by two orders of magnitude for alpine snow with median values ranging from 0.08 N/m (non-linear) to 0.18 N/m (LEFM) for median slab density around 200 kg/m3. Schulson and Duval (2009) estimated the fracture energy of solid ice (mode I) to be about 0.22-1 N/m which yields rough theoretical limits of about 0.05- 0.2 N/m for density 200 kg/m3 when the ice volume fraction is accounted for. Mode I results from lab tests (Sigrist, 2006) gave 0.1 N/m (200 kg/m3). The median effective mode II shear fracture toughness was calculated between 0.31 to 0.35 kPa(m)1/2 for the avalanche data. All the fracture energy results are much lower than previously calculated from propagation saw tests (PST) results for a weak layer collapse model (1.3 N/m) (Schweizer et al., 2011). The differences are related to model assumptions and estimates of the effective slab modulus. The calculations in this paper apply to quasi-static deformation and mode II weak layer fracture whereas the weak layer collapse model is more appropriate for dynamic conditions which follow fracture initiation (McClung and Borstad, 2012). References: Bažant, Z.P. et al. (2003) Size effect law and fracture mechanics of the triggering of dry snow slab avalanches, J. Geophys. Res. 108(B2): 2119, doi:10.1029/2002JB))1884.2003. McClung, D.M. and C.P. Borstad (2012) Deformation and energy of dry snow slabs prior to fracture propagation, J. Glaciol. 58(209), 2012 doi:10.3189/2012JoG11J009. Schulson, E.M and P. Duval (2009) Creep and fracture of ice, Cambridge University Press, 401 pp. Schweizer, J. et al. (2011) Measurements of weak layer fracture energy, Cold Reg. Sci. and Tech. 69: 139-144. Sigrist, C. (2006) Measurement of fracture mechanical properties of snow and application to dry snow slab avalanche release, Ph.D thesis: 16736, ETH, Zuerich: 139 pp.

Combined Characterization of the Time Response of Impression Materials via Traditional and FTIR Measurements

PubMed Central

Derchi, Giacomo; Manca, Enrico; Shayganpour, Amirreza; Barone, Antonio; Diaspro, Alberto; Salerno, Marco

2015-01-01

We investigated the temporal response of four dental impression materials, namely three siloxanes (Imprint 4, Flexitime, Aquasil) and one polyether (Impregum). The null hypothesis was that the nominal working times are confirmed by instrumental laboratory tests. We also aimed to identify alternative techniques with strong physical-chemical background for the assessment of temporal response. Traditional characterization was carried out by shark fin test device and durometer at both ambient and body temperature. Additionally, Fourier-transform infrared spectroscopy was performed at room temperature. From shark fin height and Shore hardness versus time the working time and the setting time of the materials were evaluated, respectively. These were in reasonable agreement with the nominal values, except for Impregum, which showed longer working time. Spectroscopy confirmed the different character of the two types of materials, and provided for Imprint 4 and Aquasil an independent evaluation of both evolution times, consistent with the results of the other techniques. Shark fin test and durometer measurements showed deviations in setting time, low sensitivity to temperature for Flexitime, and longer working time at higher temperature for Impregum. Deviations of working time appear in operating conditions from what specified by the manufacturers. Fourier-transform infrared spectroscopy can provide insight in the correlation between material properties and their composition and structure.

Do genetic modifiers of high-density lipoprotein cholesterol and triglyceride levels also modify their response to a lifestyle intervention in the setting of obesity and type-2 diabetes mellitus?: The Action for Health in Diabetes (Look AHEAD) study.

PubMed

Huggins, Gordon S; Papandonatos, George D; Erar, Bahar; Belalcazar, L Maria; Brautbar, Ariel; Ballantyne, Christie; Kitabchi, Abbas E; Wagenknecht, Lynne E; Knowler, William C; Pownall, Henry J; Wing, Rena R; Peter, Inga; McCaffery, Jeanne M

2013-08-01

High-density lipoprotein cholesterol (HDL-C) and triglycerides are cardiovascular risk factors susceptible to lifestyle behavior modification and genetics. We hypothesized that genetic variants identified by genome-wide association studies as associated with HDL-C or triglyceride levels modify 1-year treatment response to an intensive lifestyle intervention, relative to a usual care of diabetes mellitus support and education. We evaluated 82 single-nucleotide polymorphisms, which represent 31 loci demonstrated by genome-wide association studies to be associated with HDL-C and triglycerides, in 3561 participants who consented for genetic studies and met eligibility criteria. Variants associated with higher baseline HDL-C levels, cholesterol ester transfer protein (CETP) rs3764261 and hepatic lipase (LIPC) rs8034802, were found to be associated with HDL-C increases with intensive lifestyle intervention (P=0.0038 and 0.013, respectively) and had nominally significant treatment interactions (P=0.047 and 0.046, respectively). The fatty acid desaturase-2 rs1535 variant, associated with low baseline HDL-C (P=0.017), was associated with HDL-C increases with intensive lifestyle intervention (0.0037) and had a nominal treatment interaction (P=0.035). Apolipoprotein B (rs693) and LIPC (rs8034802) single-nucleotide polymorphisms showed nominally significant associations with HDL-C and triglyceride changes with intensive lifestyle intervention and a treatment interaction (P<0.05). Phosphatidylglycerophosphate synthase-1 single-nucleotide polymorphisms (rs4082919) showed the most significant triglyceride treatment interaction in the full cohort (P=0.0009). This is the first study to identify genetic variants modifying lipid responses to a randomized lifestyle behavior intervention in overweight or obese individuals with diabetes mellitus. The effects of genetic factors on lipid changes may differ from the effects on baseline lipids and are modifiable by behavioral intervention.

Do Genetic Modifiers of HDL-C and Triglyceride Levels also Modify Their Response to a Lifestyle Intervention in the Setting of Obesity and Type-2 Diabetes Mellitus? The Look AHEAD Study

PubMed Central

Huggins, Gordon S.; Papandonatos, George D.; Erar, Bahar; Belalcazar, L. Maria; Brautbar, Ariel; Ballantyne, Christie; Kitabchi, Abbas E.; Wagenknecht, Lynne E.; Knowler, William C.; Pownall, Henry J.; Wing, Rena R.; Peter, Inga; McCaffery, Jeanne M.

2014-01-01

Background High-density lipoprotein cholesterol (HDL-C) and triglycerides are cardiovascular risk factors susceptible to lifestyle behavior modification and genetics. We hypothesized that genetic variants identified by genome-wide association studies (GWASs) as associated with HDL-C or triglyceride levels will modify 1-year treatment response to an intensive lifestyle intervention (ILI), relative to a usual care of diabetes support and education (DSE). Methods and Results We evaluated 82 SNPs, representing 31 loci demonstrated by GWAS to be associated with HDL-C and/or triglycerides, in 3,561 participants who consented for genetic studies and met eligibility criteria. Variants associated with higher baseline HDL-C levels, cholesterol ester transfer protein (CETP) rs3764261 and hepatic lipase (LIPC) rs8034802, were found to be associated with HDL-C increases with ILI (p=0.0038 and 0.013, respectively) and had nominally significant treatment interactions (p=0.047 and 0.046, respectively). The fatty acid desaturase-2 (FADS-2) rs1535 variant, associated with low baseline HDL-C (p=0.017), was associated with HDL-C increases with ILI (0.0037) and had a nominal treatment interaction (p= 0.035). ApoB (rs693) and LIPC (rs8034802) SNPs showed nominally significant associations with HDL-C and triglyceride changes with ILI and a treatment interaction (p<0.05). A PGS1 SNP (rs4082919) showed the most significant triglyceride treatment interaction in the full cohort (p=0.0009). Conclusions This is the first study to identify genetic variants modifying lipid responses to a randomized lifestyle behavior intervention in overweight/obese diabetic individuals. The effect of genetic factors on lipid changes may differ from the effects on baseline lipids and are modifiable by behavioral intervention. PMID:23861364

Optimal and robust control of a class of nonlinear systems using dynamically re-optimised single network adaptive critic design

NASA Astrophysics Data System (ADS)

Tiwari, Shivendra N.; Padhi, Radhakant

2018-01-01

Following the philosophy of adaptive optimal control, a neural network-based state feedback optimal control synthesis approach is presented in this paper. First, accounting for a nominal system model, a single network adaptive critic (SNAC) based multi-layered neural network (called as NN1) is synthesised offline. However, another linear-in-weight neural network (called as NN2) is trained online and augmented to NN1 in such a manner that their combined output represent the desired optimal costate for the actual plant. To do this, the nominal model needs to be updated online to adapt to the actual plant, which is done by synthesising yet another linear-in-weight neural network (called as NN3) online. Training of NN3 is done by utilising the error information between the nominal and actual states and carrying out the necessary Lyapunov stability analysis using a Sobolev norm based Lyapunov function. This helps in training NN2 successfully to capture the required optimal relationship. The overall architecture is named as 'Dynamically Re-optimised single network adaptive critic (DR-SNAC)'. Numerical results for two motivating illustrative problems are presented, including comparison studies with closed form solution for one problem, which clearly demonstrate the effectiveness and benefit of the proposed approach.

A Strategic Planning Process Model for Distance Education

ERIC Educational Resources Information Center

Pisel, Kenneth P.

2008-01-01

As more institutions seek to implement or expand distance learning programs, it becomes critical to integrate distance learning programs into broader strategic visions and plans. Using the informed opinion from a panel of peer-nominated experts via iterative Delphi questionnaires, a 10-phased strategic planning process model for distance education…

Power and Agency in Language Policy Appropriation

ERIC Educational Resources Information Center

Johnson, David Cassels; Johnson, Eric J.

2015-01-01

In this article we proffer a theoretical model for analyzing power in language policy processes and incorporate ethnographic data to illustrate the usefulness of the model. Grounded in an ethnographic project in the US state of Washington, we examine how nominally identical school district-level programs, which are funded under the same…

10 CFR 431.36 - Compliance Certification.

Code of Federal Regulations, 2014 CFR

2014-01-01

... EQUIPMENT Electric Motors Certification § 431.36 Compliance Certification. (a) General. A manufacturer or private labeler shall not distribute in commerce any basic model of an electric motor which is subject to... efficiency for each basic model of electric motor distributed is not less than the minimum nominal full load...

10 CFR 431.36 - Compliance Certification.

Code of Federal Regulations, 2013 CFR

2013-01-01

... EQUIPMENT Electric Motors Certification § 431.36 Compliance Certification. (a) General. A manufacturer or private labeler shall not distribute in commerce any basic model of an electric motor which is subject to... efficiency for each basic model of electric motor distributed is not less than the minimum nominal full load...

The dual role of friendship and antipathy relations in the marginalization of overweight children in their peer networks: The TRAILS Study.

PubMed

de la Haye, Kayla; Dijkstra, Jan Kornelis; Lubbers, Miranda J; van Rijsewijk, Loes; Stolk, Ronald

2017-01-01

Weight-based stigma compromises the social networks of overweight children. To date, research on the position of overweight children in their peer network has focused only on friendship relations, and not on negative relationship dimensions. This study examined how overweight was associated with relations of friendship and dislike (antipathies) in the peer group. Exponential random graph models (ERGM) were used to examine friendship and antipathy relations among overweight children and their classmates, using a sub-sample from the TRacking Adolescents' Individual Lives Survey (N = 504, M age 11.4). Findings showed that overweight children were less likely to receive friendship nominations, and were more likely to receive dislike nominations. Overweight children were also more likely than their non-overweight peers to nominate classmates that they disliked. Together, the results indicate that positive and negative peer relations are impacted by children's weight status, and are relevant to addressing the social marginalization of overweight children.

Terminal altitude maximization for Mars entry considering uncertainties

NASA Astrophysics Data System (ADS)

Cui, Pingyuan; Zhao, Zeduan; Yu, Zhengshi; Dai, Juan

2018-04-01

Uncertainties present in the Mars atmospheric entry process may cause state deviations from the nominal designed values, which will lead to unexpected performance degradation if the trajectory is designed merely based on the deterministic dynamic model. In this paper, a linear covariance based entry trajectory optimization method is proposed considering the uncertainties presenting in the initial states and parameters. By extending the elements of the state covariance matrix as augmented states, the statistical behavior of the trajectory is captured to reformulate the performance metrics and path constraints. The optimization problem is solved by the GPOPS-II toolbox in MATLAB environment. Monte Carlo simulations are also conducted to demonstrate the capability of the proposed method. Primary trading performances between the nominal deployment altitude and its dispersion can be observed by modulating the weights on the dispersion penalty, and a compromised result referring to maximizing the 3σ lower bound of the terminal altitude is achieved. The resulting path constraints also show better satisfaction in a disturbed environment compared with the nominal situation.

The Embeddedness of Adolescent Friendship Nominations: The Formation of Social Capital in Emergent Network Structures

PubMed Central

Frank, Kenneth A.; Muller, Chandra; Mueller, Anna S.

2014-01-01

Although research on social embeddedness and social capital con-firms the value of friendship networks, little has been written about how social relations form and are structured by social institutions. Using data from the Adolescent Health and Academic Achievement study and the National Longitudinal Study of Adolescent Health, the authors show that the odds of a new friendship nomination were 1.77 times greater within clusters of high school students taking courses together than between them. The estimated effect cannot be attributed to exposure to peers in similar grade levels, indirect friendship links, or pair-level course overlap, and the finding is robust to alternative model specifications. The authors also show how tendencies associated with status hierarchy inhering in triadic friendship nominations are neutralized within the clusters. These results have implications for the production and distribution of social capital within social systems such as schools, giving the clusters social salience as “local positions.” PMID:25364011

Cooling towers, the neglected energy conservations and money making machine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burger, R.

1996-12-31

The heat Rejection Industry defines a nominal cooling tower as circulating three gallons of water per minute (GPM) per ton of refrigeration from entering the tower at 95 {degrees}F, Hot Water temperature (HWT), Leaving at 85{degrees}F Cold Water Temperature (CWT) at a Design Wet Bulb of 70{degrees}F (WBT). Manufacturers then provide a selection chart based on various wet bulb temperatures and HWTs. The wet bulb fluctuates and varies throughout the world since it is the combination ambient temperature, relative humidity, and/or dew point. Different HWT and CWT requirements are usually charted as they change, so that the user can selectmore » the nominal cooling tower model recommended by the manufacturer. In the specification of cooling towers it is necessary to clearly understand the definition of nominal cooling tower, and to make sure the specification you need addressed can be met by the system you purchase. This should be tested prior to final acceptance.« less

Genes related to sex steroids, neural growth, and social-emotional behavior are associated with autistic traits, empathy, and Asperger syndrome.

PubMed

Chakrabarti, B; Dudbridge, F; Kent, L; Wheelwright, S; Hill-Cawthorne, G; Allison, C; Banerjee-Basu, S; Baron-Cohen, S

2009-06-01

Genetic studies of autism spectrum conditions (ASC) have mostly focused on the "low functioning" severe clinical subgroup, treating it as a rare disorder. However, ASC is now thought to be relatively common ( approximately 1%), and representing one end of a quasi-normal distribution of autistic traits in the general population. Here we report a study of common genetic variation in candidate genes associated with autistic traits and Asperger syndrome (AS). We tested single nucleotide polymorphisms in 68 candidate genes in three functional groups (sex steroid synthesis/transport, neural connectivity, and social-emotional responsivity) in two experiments. These were (a) an association study of relevant behavioral traits (the Empathy Quotient (EQ), the Autism Spectrum Quotient (AQ)) in a population sample (n=349); and (b) a case-control association study on a sample of people with AS, a "high-functioning" subgroup of ASC (n=174). 27 genes showed a nominally significant association with autistic traits and/or ASC diagnosis. Of these, 19 genes showed nominally significant association with AQ/EQ. In the sex steroid group, this included ESR2 and CYP11B1. In the neural connectivity group, this included HOXA1, NTRK1, and NLGN4X. In the socio-responsivity behavior group, this included MAOB, AVPR1B, and WFS1. Fourteen genes showed nominally significant association with AS. In the sex steroid group, this included CYP17A1 and CYP19A1. In the socio-emotional behavior group, this included OXT. Six genes were nominally associated in both experiments, providing a partial replication. Eleven genes survived family wise error rate (FWER) correction using permutations across both experiments, which is greater than would be expected by chance. CYP11B1 and NTRK1 emerged as significantly associated genes in both experiments, after FWER correction (P<0.05). This is the first candidate-gene association study of AS and of autistic traits. The most promising candidate genes require independent replication and fine mapping.

76 FR 52016 - NASA Federal Advisory Committees; Nominations and Self-Nominations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-19

... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION [Notice: (11- 075)] NASA Federal Advisory Committees; Nominations and Self- Nominations AGENCY: National Aeronautics and Space Administration. ACTION: Public... the Federal Advisory Committee Act, Public Law 92-463, as amended, the National Aeronautics and Space...

7 CFR 987.124 - Nomination and polling.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Nomination and polling. 987.124 Section 987.124 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... IN RIVERSIDE COUNTY, CALIFORNIA Administrative Rules Nominations § 987.124 Nomination and polling. (a...

7 CFR 1150.133 - Nominations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 9 2012-01-01 2012-01-01 false Nominations. 1150.133 Section 1150.133 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order National Dairy Promotion and Research Board § 1150.133 Nominations. Nominations for members of the...

7 CFR 1150.133 - Nominations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 9 2013-01-01 2013-01-01 false Nominations. 1150.133 Section 1150.133 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Order National Dairy Promotion and Research Board § 1150.133 Nominations. Nominations for members of the...

NekNominate: Social Norms, Social Media, and Binge Drinking.

PubMed

Wombacher, Kevin; Reno, Jenna E; Veil, Shari R

2017-05-01

This study examines the social-media-based binge drinking game NekNominate and how this phenomenon is related to social norms. NekNominate is a game wherein players are nominated to film themselves "neking" or chugging copious amounts of alcohol or drinking alcohol in a novel or humorous manner. The player then nominates other players via social media who then have a specific timeframe in which they must complete their challenge or face ridicule. Health communication research on drinking behaviors has often looked at the role of social norms in determining these behaviors. News stories (n = 44) of NekNominate and tweets (n = 851) culled using the hashtag #NekNominate during three different time periods are analyzed to identify the normative forces at play in this recent phenomenon.

Design of freeform optics for an ophthalmological application

NASA Astrophysics Data System (ADS)

Sieber, Ingo; Yi, Allen; Li, Likai; Beckert, Erik; Steinkopf, Ralf; Gengenbach, Ulrich

2014-05-01

Optical freeform surfaces are gaining importance in different optical applications. A huge demand arises e.g. in the fields of automotive and medical engineering. Innovative systems often need high-quality and high-volume optics. Injectionmoulded polymer optics represents a cost-efficient solution. However, it has to be ensured that the tight requirements with respect to the system's performance are met by the replicated freeform optics. To reach this goal, it is not sufficient to only characterise the manufactured optics by peak-to-valley or rms data describing a deviation from the nominal surface. Instead, optical performance of the manufactured freeform optics has to be analysed and compared with the performance of the nominal surface. This can be done by integrating the measured surface data of the manufactured freeform optics into the optical simulation model. The feedback of the measured surface data into the model allows for a simulation of the optical performance of the optical subsystem containing the real freeform optics manufactured. Hence, conclusions can be drawn as to whether the specifications with respect to e.g. imaging quality are met by the real manufactured optics. This approach will be presented using an Alvarez-Humphrey optics as an example of a tuneable optics of an ophthalmological application. The focus of this article will be on design for manufacturing the freeform optics, the integration of the measured surface data into the optical simulation model, simulation of the optical performance, and analysis in comparison to the nominal surface.

SU-E-J-152: Evaluation of TrueBeam OBI V. 1.5 CBCT Performance in An Adaptive RT Environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gardner, S; Studenski, M; Giaddui, T

2014-06-01

Purpose: To evaluate the image quality and imaging dose of the Varian TrueBeam OBIv.1.5 CBCT system in a clinical adaptive radiation therapy environment, simulated by changing phantom thickness. Methods: Various OBI CBCT protocols(Head, Pelvis, Thorax, Spotlight) were used to acquire images of Catphan504 phantom(nominal phantom thickness and 10 cm additional phantom thickness). The images were analyzed for low contrast detectability(CNR), uniformity(UI), and HU sensitivity. These results were compared to the same image sets for planning CT(pCT)(GE LightSpeed 16- slice). Imaging dose measurements were performed with Gafchromic XRQA2 film for various OBI protocols (Pelvis, Thorax, Spotlight) in a pelvic-sized phantom(nominal thicknessmore » and 4cm additional thickness). Dose measurements were acquired in the interior and at the surface of the phantom. Results: The nominal CNR[additional thickness CNR] for OBI was—Pelvis:1.45[0.81],Thorax:0.86[0.48], Spotlight:0.67[0.39],Head:0.28 [0.10]. The nominal CNR[additional thickness CNR] for pCT was— Pelvis:0.87[0.41],Head:0.60[0.22]. The nominal UI[additional thickness UI] for OBI was—Pelvis:11.5[24.1],Thorax:17.0[20.6], Spotlight:23.2[23.2], Head:15.6[59.9]. The nominal UI[additional thickness UI] for pCT was— Pelvis:9.2[8.6],Head:2.1[2.9]. The HU difference(averaged over all material inserts) between nominal and additional thickness scans for OBI: 8.26HU(Pelvis), 33.39HU(Thorax), 178.98HU(Head), 108.20HU (Spotlight); for pCT: 16.00HU(Pelvis), 19.85HU(Head). Uncertainties in electron density were calculated based on HU values with varying phantom thickness. Average electron-density deviations (ρ(water)=1)for GE-Pelvis, GE-Head, OBI-Pelvis, OBI-Thorax, OBI-Spotlight, and OBI-Head were: 0.0182, 0.0180, 0.0058, 0.0478, 0.2750, and 0.3115, respectively.The average phantom interior dose was(OBI-nominal):2.35cGy(Pelvis), 0.60cGy(Thorax), 1.87cGy(Spotlight); OBI-increased thickness: 1.77cGy(Pelvis), 0.43cGy(Thorax), 1.53cGy (Spotlight). Average surface dose(OBI-nominal): 2.29cGy(Pelvis), 0.56cGy(Thorax), 1.79cGy (Spotlight); OBI-increased thickness: 1.94cGy(Pelvis), 0.48cGy(Thorax), 1.47cGy (Spotlight). Conclusion: The OBI-Pelvis protocol offered comparable CNR and HU constancy to pCT for each geometry; other protocols, particularly Spotlight and Head, exhibited lower HU constancy and CNR. The uniformity of pCT was superior to OBI for all protocols. CNR and UI were degraded for both systems/scan types with increased thickness. The OBI interior dose decreased by approximately 30% with additional thickness. This work was funded, in part, under a grant with the Pennsylvania Department of Health. The Department of Health specifically declaims responsibility for any analyses, interpretations, or conclusions.« less

IRIS Toxicological Review of 2-Hexanone (External Review ...

EPA Pesticide Factsheets

EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of 2-hexanone that will appear on the Integrated Risk Information System (IRIS) database. Peer review is meant to ensure that science is used credibly and appropriately in derivation of the dose-response assessments and toxicological characterization. 2-Hexanone was nominated for IRIS assessment because of its frequent detection at sites nation-wide and its occurrence as a byproduct of certain industrial processes.

Crash Analysis of Automotive Chassis Structure Considering the Strain Hardening Effect

NASA Astrophysics Data System (ADS)

Mashalkar, A. S.; Parvekar, R. P.

2011-08-01

The work hardening during the forming process is generally ignored in crash analysis. This paper presents computational details of the effect of forming process on crash response of typical Sports Utility Vehicles (SUV). Forming results for front panels of a medium-sized SUV were calculated using Hyperform and LS Dyna. These were imported into the crash model and crash results compared with and without the forming effects. Time taken to generate the forming data by a variety of methods is quantified and the trade-off between time taken and accuracy is examined. LS-DYNA was used for both forming and crash simulations. The effect of thickness, work hardening and residual stresses on the crashworthiness results is measured; crash response is seen to be significantly affected when the effects of forming are included. The paper proposes a systematic method to transfer data from the forming analysis to crashworthiness analysis (both using LS-DYNA), allowing thickness, residual stress and plastic strain data selectively or in combination to be used to initialise the crash model. The relative effect of each of these forming parameters has been examined and the importance of, work hardening on the crash response of the stamping front rail has been identified. A significant change in energy absorption, peak force and stroke of the front rail was predicted, indicating a far stiffer response in the formed rail than would be expected based on the nominal material properties. Therefore, forming effects should be accounted for in vehicle crashworthiness predictions.

The Production of Nominal and Verbal Inflection in an Agglutinative Language: Evidence from Hungarian

PubMed Central

Peckham, Don; Szanka, Szilvia; Gazso, Dorottya; Lovassy, Noemi; Ullman, Michael T.

2015-01-01

The contrast between regular and irregular inflectional morphology has been useful in investigating the functional and neural architecture of language. However, most studies have examined the regular/irregular distinction in non-agglutinative Indo-European languages (primarily English) with relatively simple morphology. Additionally, the majority of research has focused on verbal rather than nominal inflectional morphology. The present study attempts to address these gaps by introducing both plural and past tense production tasks in Hungarian, an agglutinative non-Indo-European language with complex morphology. Here we report results on these tasks from healthy Hungarian native-speaking adults, in whom we examine regular and irregular nominal and verbal inflection in a within-subjects design. Regular and irregular nouns and verbs were stem on frequency, word length, and phonological structure, and both accuracy and response times were acquired. The results revealed that the regular/irregular contrast yields similar patterns in Hungarian, for both nominal and verbal inflection, as in previous studies of non-agglutinative Indo-European languages: the production of irregular inflected forms was both less accurate and slower than of regular forms, both for plural and past-tense inflection. The results replicate and extend previous findings to an agglutinative language with complex morphology. Together with previous studies, the evidence suggests that the regular/irregular distinction yields a basic behavioral pattern that holds across language families and linguistic typologies. Finally, the study sets the stage for further research examining the neurocognitive substrates of regular and irregular morphology in an agglutinative non-Indo-European language. PMID:25769039

45 CFR 1801.18 - Limitations on nominations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 45 Public Welfare 4 2014-10-01 2014-10-01 false Limitations on nominations. 1801.18 Section 1801.18 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.18 Limitations on nominations. A candidate...

45 CFR 1801.18 - Limitations on nominations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 45 Public Welfare 4 2011-10-01 2011-10-01 false Limitations on nominations. 1801.18 Section 1801.18 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.18 Limitations on nominations. A candidate...

45 CFR 1801.18 - Limitations on nominations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 45 Public Welfare 4 2010-10-01 2010-10-01 false Limitations on nominations. 1801.18 Section 1801.18 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.18 Limitations on nominations. A candidate...

45 CFR 1801.18 - Limitations on nominations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 45 Public Welfare 4 2012-10-01 2012-10-01 false Limitations on nominations. 1801.18 Section 1801.18 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.18 Limitations on nominations. A candidate...

45 CFR 1801.18 - Limitations on nominations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 4 2013-10-01 2013-10-01 false Limitations on nominations. 1801.18 Section 1801.18 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.18 Limitations on nominations. A candidate...

7 CFR 1220.203 - Nominations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... CONSUMER INFORMATION Soybean Promotion and Research Order United Soybean Board § 1220.203 Nominations. All... be filled. (e) Nominations may be submitted in order of preference and for the initial Board, in order of preference for staggered terms. Should the Secretary reject any nomination submitted and there...

7 CFR 932.31 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Failure to nominate. 932.31 Section 932.31 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Olive Administrative Committee § 932.31 Failure to nominate. If nominations for any...

7 CFR 953.20 - Failure to nominate.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Failure to nominate. 953.20 Section 953.20 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... STATES Order Regulating Handling Administrative Committee § 953.20 Failure to nominate. If nominations...

7 CFR 953.20 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Failure to nominate. 953.20 Section 953.20 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... STATES Order Regulating Handling Administrative Committee § 953.20 Failure to nominate. If nominations...

7 CFR 932.31 - Failure to nominate.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Failure to nominate. 932.31 Section 932.31 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Regulating Handling Olive Administrative Committee § 932.31 Failure to nominate. If nominations for any...

7 CFR 927.25 - Failure to nominate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Failure to nominate. 927.25 Section 927.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Administrative Bodies § 927.25 Failure to nominate. In the event nominations...

7 CFR 932.31 - Failure to nominate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Failure to nominate. 932.31 Section 932.31 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Olive Administrative Committee § 932.31 Failure to nominate. If nominations for any...

7 CFR 953.20 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 953.20 Section 953.20 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... STATES Order Regulating Handling Administrative Committee § 953.20 Failure to nominate. If nominations...

7 CFR 917.26 - Failure to nominate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Failure to nominate. 917.26 Section 917.26 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... CALIFORNIA Order Regulating Handling Administrative Bodies § 917.26 Failure to nominate. If nominations are...

7 CFR 927.25 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Failure to nominate. 927.25 Section 927.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Administrative Bodies § 927.25 Failure to nominate. In the event nominations...

7 CFR 917.26 - Failure to nominate.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Failure to nominate. 917.26 Section 917.26 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... CALIFORNIA Order Regulating Handling Administrative Bodies § 917.26 Failure to nominate. If nominations are...

7 CFR 927.25 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 927.25 Section 927.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Administrative Bodies § 927.25 Failure to nominate. In the event nominations...

7 CFR 917.26 - Failure to nominate.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Failure to nominate. 917.26 Section 917.26 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... CALIFORNIA Order Regulating Handling Administrative Bodies § 917.26 Failure to nominate. If nominations are...

7 CFR 917.26 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Failure to nominate. 917.26 Section 917.26 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... CALIFORNIA Order Regulating Handling Administrative Bodies § 917.26 Failure to nominate. If nominations are...

7 CFR 932.31 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 932.31 Section 932.31 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Olive Administrative Committee § 932.31 Failure to nominate. If nominations for any...

7 CFR 917.26 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 917.26 Section 917.26 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... CALIFORNIA Order Regulating Handling Administrative Bodies § 917.26 Failure to nominate. If nominations are...

7 CFR 932.31 - Failure to nominate.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Failure to nominate. 932.31 Section 932.31 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Regulating Handling Olive Administrative Committee § 932.31 Failure to nominate. If nominations for any...

7 CFR 927.25 - Failure to nominate.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Failure to nominate. 927.25 Section 927.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Order Regulating Handling Administrative Bodies § 927.25 Failure to nominate. In the event nominations...

7 CFR 927.25 - Failure to nominate.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Failure to nominate. 927.25 Section 927.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Order Regulating Handling Administrative Bodies § 927.25 Failure to nominate. In the event nominations...

Simulation of vertical dynamic vehicle-track interaction in a railway crossing using Green's functions

NASA Astrophysics Data System (ADS)

Li, X.; Torstensson, P. T.; Nielsen, J. C. O.

2017-12-01

Vertical dynamic vehicle-track interaction in the through route of a railway crossing is simulated in the time domain based on a Green's function approach for the track in combination with an implementation of Kalker's variational method to solve the non-Hertzian, and potentially multiple, wheel-rail contact. The track is described by a linear, three-dimensional and non-periodic finite element model of a railway turnout accounting for the variations in rail cross-sections and sleeper lengths, and including baseplates and resilient elements. To reduce calculation time due to the complexity of the track model, involving a large number of elements and degrees-of-freedom, a complex-valued modal superposition with a truncated mode set is applied before the impulse response functions are calculated at various positions along the crossing panel. The variation in three-dimensional contact geometry of the crossing and wheel is described by linear surface elements. In each time step of the contact detection algorithm, the lateral position of the wheelset centre is prescribed but the contact positions on wheel and rail are not, allowing for an accurate prediction of the wheel transition between wing rail and crossing rail. The method is demonstrated by calculating the wheel-rail impact load and contact stress distribution for a nominal S1002 wheel profile passing over a nominal crossing geometry. A parameter study is performed to determine the influence of vehicle speed, rail pad stiffness, lateral wheelset position and wheel profile on the impact load generated at the crossing. It is shown that the magnitude of the impact load is more influenced the wheel-rail contact geometry than by the selection of rail pad stiffness.

Occupant Protection at NASA

NASA Technical Reports Server (NTRS)

Somers, Jeffrey; Granderson, Brad; Scheuring, Rick

2010-01-01

This slide presentation reviews NASA's efforts to arrive at protection of occupants of the ORION space craft on landing. An Abbreviated Injury Scale (AIS) has been developed, it is an anatomically-based, consensus-derived, global severity scoring system that classifies each injury by body region according to its relative importance on a 6-point ordinal scale. It reviews an Operationmally Relevant Injury Scale (ORIS), a classification methodology, and shows charts that detail the results of applying this ORIS to the injury databases. One chart uses NASCAR injury classification. It discusses providing a context for the level of risk inherent in the Orion landings in terms that people understand and have a sense for. For example is the risk of injury during an Orion landing roughly the same, better or worse than: An aircraft carrier landing, a NASCAR crash, or a helicopter crash, etc? The data for NASCAR and Indy Racing league (IRL) racing crash and injury data was reviewed. The risk from the Air Force, Navy, and Army injury data was also reviewed. Past NASA and the Soyuz programs injury risks are also reviewed. The work is an attempt to formulate a recommendation to the Orion Project for an acceptable level of injury risk associated with Nominal and Off-Nominal landing cases. The presentation also discusses the data mining and use of the data to Validate NASA Operationally-Relevant Injury Scale (NORIS) / Military Operationally-Relevant Injury Scale (MORIS), developing injury risk criteria, the types of data that are required, NASCAR modeling techniques and crash data, and comparison with the Brinkley model. The development of injury risk curves for each biodynamic response parameter is discussed. One of the main outcomes of this work is to establish an accurate Automated Test Dummy (ATD) that can be used to measure human tolerances.

The Livingstone Model of a Main Propulsion System

NASA Technical Reports Server (NTRS)

Bajwa, Anupa; Sweet, Adam; Korsmeyer, David (Technical Monitor)

2003-01-01

Livingstone is a discrete, propositional logic-based inference engine that has been used for diagnosis of physical systems. We present a component-based model of a Main Propulsion System (MPS) and say how it is used with Livingstone (L2) in order to implement a diagnostic system for integrated vehicle health management (IVHM) for the Propulsion IVHM Technology Experiment (PITEX). We start by discussing the process of conceptualizing such a model. We describe graphical tools that facilitated the generation of the model. The model is composed of components (which map onto physical components), connections between components and constraints. A component is specified by variables, with a set of discrete, qualitative values for each variable in its local nominal and failure modes. For each mode, the model specifies the component's behavior and transitions. We describe the MPS components' nominal and fault modes and associated Livingstone variables and data structures. Given this model, and observed external commands and observations from the system, Livingstone tracks the state of the MPS over discrete time-steps by choosing trajectories that are consistent with observations. We briefly discuss how the compiled model fits into the overall PITEX architecture. Finally we summarize our modeling experience, discuss advantages and disadvantages of our approach, and suggest enhancements to the modeling process.

Computational aspects of geometric correction data generation in the LANDSAT-D imagery processing

NASA Technical Reports Server (NTRS)

Levine, I.

1981-01-01

A method is presented for systematic and geodetic correction data calculation. It is based on presentation of image distortions as a sum of nominal distortions and linear effects caused by variation of the spacecraft position and attitude variables from their nominals. The method may be used for both MSS and TM image data and it is incorporated into the processing by means of mostly offline calculations. Modeling shows that the maximal of the method are of the order of 5m at the worst point in a frame; the standard deviations of the average errors less than .8m.

75 FR 44793 - Consumer Advisory Council Solicitation of Nominations for Membership

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-29

... to nominate qualified individuals for appointment to its Consumer Advisory Council, whose membership... affiliation, title, address, phone and fax numbers, and e-mail address. Individuals may nominate themselves... does not limit consideration to individuals nominated by the public when making its selection. Council...

36 CFR 60.11 - Requests for nominations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... and appears to meet the National Register criteria for evaluation in § 60.4. If the nomination form is... any person or organization submitting a completed National Register nomination form or requesting consideration for any previously prepared nomination form on record with the State or Federal agency. The...

7 CFR 1219.34 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 10 2012-01-01 2012-01-01 false Failure to nominate. 1219.34 Section 1219.34 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING....34 Failure to nominate. In any case in which producers or importers fail to nominate individuals for...

7 CFR 915.24 - Failure to nominate.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Failure to nominate. 915.24 Section 915.24 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Regulating Handling Administrative Body § 915.24 Failure to nominate. If nominations are not made within the...

7 CFR 915.24 - Failure to nominate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Failure to nominate. 915.24 Section 915.24 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Administrative Body § 915.24 Failure to nominate. If nominations are not made within the...

7 CFR 1219.34 - Failure to nominate.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 10 2013-01-01 2013-01-01 false Failure to nominate. 1219.34 Section 1219.34 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING....34 Failure to nominate. In any case in which producers or importers fail to nominate individuals for...

7 CFR 915.24 - Failure to nominate.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Failure to nominate. 915.24 Section 915.24 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Regulating Handling Administrative Body § 915.24 Failure to nominate. If nominations are not made within the...

7 CFR 948.57 - Failure to nominate.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Failure to nominate. 948.57 Section 948.57 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Order Regulating Handling Committees § 948.57 Failure to nominate. If nominations are not made pursuant...

7 CFR 948.57 - Failure to nominate.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Failure to nominate. 948.57 Section 948.57 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Order Regulating Handling Committees § 948.57 Failure to nominate. If nominations are not made pursuant...

7 CFR 948.57 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 948.57 Section 948.57 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Committees § 948.57 Failure to nominate. If nominations are not made pursuant...

7 CFR 1219.34 - Failure to nominate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 10 2011-01-01 2011-01-01 false Failure to nominate. 1219.34 Section 1219.34 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING....34 Failure to nominate. In any case in which producers or importers fail to nominate individuals for...

7 CFR 916.24 - Failure to nominate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Failure to nominate. 916.24 Section 916.24 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Administrative Body § 916.24 Failure to nominate. If nominations are not made within the...

7 CFR 916.24 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 916.24 Section 916.24 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Administrative Body § 916.24 Failure to nominate. If nominations are not made within the...

7 CFR 948.57 - Failure to nominate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Failure to nominate. 948.57 Section 948.57 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Committees § 948.57 Failure to nominate. If nominations are not made pursuant...

7 CFR 948.57 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Failure to nominate. 948.57 Section 948.57 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Committees § 948.57 Failure to nominate. If nominations are not made pursuant...

7 CFR 1219.34 - Failure to nominate.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 10 2014-01-01 2014-01-01 false Failure to nominate. 1219.34 Section 1219.34 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING....34 Failure to nominate. In any case in which producers or importers fail to nominate individuals for...

7 CFR 915.24 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Failure to nominate. 915.24 Section 915.24 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Administrative Body § 915.24 Failure to nominate. If nominations are not made within the...

Use of a Teacher Nomination Strategy to Screen for Autism Spectrum Disorders in General Education Classrooms: A Pilot Study

PubMed Central

Hepburn, Susan L.; DiGuiseppi, Carolyn; Rosenberg, Steven; Kaparich, Kristina; Robinson, Cordelia; Miller, Lisa

2015-01-01

Given a rising prevalence of autism spectrum disorders (ASD), this project aimed to develop and pilot test various teacher nomination strategies to identify children at risk for ASD in a timely, reliable, cost-effective manner. Sixty participating elementary school teachers evaluated 1323 children in total. Each teacher nominated students who most fit a description of ASD-associated characteristics, and completed the Autism Syndrome Screening Questionnaire (ASSQ) on every child in the classroom. The proportion of overall agreement between teacher nomination and ASSQ was 93–95%, depending upon the nomination parameters. Nomination required 15 min per class versus 3.5–5.5 h per class for the ASSQ. These results support the need for further study of teacher nomination strategies to identify children at risk for ASD. PMID:17661165

Hazardous behavior of lithium batteries. Case histories

NASA Technical Reports Server (NTRS)

Marincic, N.

1983-01-01

Case histories were described of hazardous behavior for three different cell sizes ranging in nominal capacity from 300 mAh to 12,000 Ah. Design characteristics and other facts believed to have been responsible for the cell explosions, are presented. Obvious facts are discussed as causes for hazardous behavior of lithium batteries in general and oxyhalide batteries in particular.

White Collar Work: Career Ambitions of Fiji Final Year School Students

ERIC Educational Resources Information Center

Nilan, Pam; Cavu, Paula; Tagicakiverata, Isimeli; Hazelman, Emily

2006-01-01

The career ambitions of 1012 pupils in the final years of secondary schooling in Fiji were surveyed. The range of careers they nominated was very narrow, with teaching, nursing and other white collar work in the majority of responses. This stands in somewhat stark contrast to projected labour force needs, and the current serious shortage of…

24 CFR 598.205 - What are the requirements for nomination?

Code of Federal Regulations, 2013 CFR

2013-04-01

... nomination? 598.205 Section 598.205 Housing and Urban Development Regulations Relating to Housing and Urban... DESIGNATIONS Nomination Procedure § 598.205 What are the requirements for nomination? (a) General. No urban... that the strategic plan described in § 598.215 will be implemented, and these governments submit its...

24 CFR 598.205 - What are the requirements for nomination?

Code of Federal Regulations, 2012 CFR

2012-04-01

... nomination? 598.205 Section 598.205 Housing and Urban Development Regulations Relating to Housing and Urban... DESIGNATIONS Nomination Procedure § 598.205 What are the requirements for nomination? (a) General. No urban... that the strategic plan described in § 598.215 will be implemented, and these governments submit its...

24 CFR 598.205 - What are the requirements for nomination?

Code of Federal Regulations, 2014 CFR

2014-04-01

... nomination? 598.205 Section 598.205 Housing and Urban Development Regulations Relating to Housing and Urban... DESIGNATIONS Nomination Procedure § 598.205 What are the requirements for nomination? (a) General. No urban... that the strategic plan described in § 598.215 will be implemented, and these governments submit its...

76 FR 71566 - Solicitation of Nominations for Membership on the National Vaccine Advisory Committee

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-18

...., Public Health Advisor, National Vaccine Program Office, Department of Health and Human Services, 200... vacated during the calendar year 2012. Nominations In accordance with the charter, persons nominated for... information should be included in the package of material submitted for each individual being nominated for...

78 FR 31939 - Solicitation of Nominations for Membership on the National Vaccine Advisory Committee

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-28

...., Public Health Advisor, National Vaccine Program Office, Department of Health and Human Services, 200... vacated during the calendar year 2013. Nominations In accordance with the charter, persons nominated for... information should be included in the package of material submitted for each individual being nominated for...

7 CFR 25.502 - Nominations by State-chartered economic development corporations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Nominations by State-chartered economic development... AND ENTERPRISE COMMUNITIES Special Rules § 25.502 Nominations by State-chartered economic development corporations. Any rural area nominated by an economic development corporation chartered by a State and...

75 FR 28782 - Extension of Period for Nominations to the National Medal of Technology and Innovation Nomination...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-24

... innovation and/or be familiar with the education, training, employment and management of technological... Innovations/Bioengineering and Biomedical Technology; Technology Management/Computing/IT/Manufacturing...] Extension of Period for Nominations to the National Medal of Technology and Innovation Nomination Evaluation...

Exploring Reference Group Effects on Teachers' Nominations of Gifted Students

ERIC Educational Resources Information Center

Rothenbusch, Sandra; Zettler, Ingo; Voss, Thamar; Lösch, Thomas; Trautwein, Ulrich

2016-01-01

Teachers are often asked to nominate students for enrichment programs for gifted children, and studies have repeatedly indicated that students' intelligence is related to their likelihood of being nominated as gifted. However, it is unknown whether class-average levels of intelligence influence teachers' nominations as suggested by theory--and…

Trajectories of Peer-Nominated Aggression: Risk Status, Predictors and Outcomes.

ERIC Educational Resources Information Center

van Lier, Pol A.C.; Crijnen, Alfons A.M.

2005-01-01

Developmental trajectories of peer-nominated aggression, risk factors at baseline, and outcomes were studied. Peer nominations of aggression were obtained annually from grades 1 to 3. Three developmental trajectories were identified: an early-onset/increasers trajectory with high levels of peer-nominated aggression at elementary school entry and…

36 CFR 60.10 - Concurrent State and Federal nominations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... cultural value. Federal agencies may nominate properties where a portion of the property is not under Federal ownership or control. (b) When a portion of the area included in a Federal nomination is not... cultural resource, the completed nomination form shall be sent to the State Historic Preservation Officer...

45 CFR 1801.10 - Nomination by institution of higher education.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 4 2013-10-01 2013-10-01 false Nomination by institution of higher education. 1801.10 Section 1801.10 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.10 Nomination by...

45 CFR 1801.11 - Annual nomination.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 45 Public Welfare 4 2011-10-01 2011-10-01 false Annual nomination. 1801.11 Section 1801.11 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.11 Annual nomination. (a) Except as provided in §§ 1801.11...

45 CFR 1801.11 - Annual nomination.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 45 Public Welfare 4 2014-10-01 2014-10-01 false Annual nomination. 1801.11 Section 1801.11 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.11 Annual nomination. (a) Except as provided in §§ 1801.11...

45 CFR 1801.11 - Annual nomination.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 4 2013-10-01 2013-10-01 false Annual nomination. 1801.11 Section 1801.11 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.11 Annual nomination. (a) Except as provided in §§ 1801.11...

45 CFR 1801.10 - Nomination by institution of higher education.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 45 Public Welfare 4 2011-10-01 2011-10-01 false Nomination by institution of higher education. 1801.10 Section 1801.10 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.10 Nomination by...

45 CFR 1801.10 - Nomination by institution of higher education.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 45 Public Welfare 4 2014-10-01 2014-10-01 false Nomination by institution of higher education. 1801.10 Section 1801.10 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.10 Nomination by...

45 CFR 1801.11 - Annual nomination.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 45 Public Welfare 4 2010-10-01 2010-10-01 false Annual nomination. 1801.11 Section 1801.11 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.11 Annual nomination. (a) Except as provided in §§ 1801.11...

45 CFR 1801.11 - Annual nomination.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 45 Public Welfare 4 2012-10-01 2012-10-01 false Annual nomination. 1801.11 Section 1801.11 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.11 Annual nomination. (a) Except as provided in §§ 1801.11...

45 CFR 1801.10 - Nomination by institution of higher education.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 45 Public Welfare 4 2012-10-01 2012-10-01 false Nomination by institution of higher education. 1801.10 Section 1801.10 Public Welfare Regulations Relating to Public Welfare (Continued) HARRY S. TRUMAN SCHOLARSHIP FOUNDATION HARRY S. TRUMAN SCHOLARSHIP PROGRAM Nominations § 1801.10 Nomination by...

7 CFR 25.502 - Nominations by State-chartered economic development corporations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 1 2013-01-01 2013-01-01 false Nominations by State-chartered economic development... AND ENTERPRISE COMMUNITIES Special Rules § 25.502 Nominations by State-chartered economic development corporations. Any rural area nominated by an economic development corporation chartered by a State and...

7 CFR 25.502 - Nominations by State-chartered economic development corporations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 1 2014-01-01 2014-01-01 false Nominations by State-chartered economic development... AND ENTERPRISE COMMUNITIES Special Rules § 25.502 Nominations by State-chartered economic development corporations. Any rural area nominated by an economic development corporation chartered by a State and...

7 CFR 25.502 - Nominations by State-chartered economic development corporations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 1 2011-01-01 2011-01-01 false Nominations by State-chartered economic development... AND ENTERPRISE COMMUNITIES Special Rules § 25.502 Nominations by State-chartered economic development corporations. Any rural area nominated by an economic development corporation chartered by a State and...

7 CFR 25.502 - Nominations by State-chartered economic development corporations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 1 2012-01-01 2012-01-01 false Nominations by State-chartered economic development... AND ENTERPRISE COMMUNITIES Special Rules § 25.502 Nominations by State-chartered economic development corporations. Any rural area nominated by an economic development corporation chartered by a State and...

77 FR 48168 - Call for Nominations for the Twin Falls District Resource Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-13

... for Nominations for the Twin Falls District Resource Advisory Council AGENCY: Bureau of Land Management, Interior. ACTION: Call for Nominations, Twin Falls District Resource Advisory Council SUMMARY: This notice requests public nominations to fill one position on the Twin Falls District Resource...

75 FR 69631 - National Medal of Technology and Innovation Nomination Evaluation Committee Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-15

... selection. NMTI Nomination Evaluation Committee members are drawn from both the public and private sectors... Technology and Innovation Nomination Evaluation Committee Meeting AGENCY: United States Patent and Trademark... Innovation (NMTI) Nomination Evaluation Committee will meet in closed session on Tuesday, November 30, 2010...

7 CFR 930.25 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Failure to nominate. 930.25 Section 930.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Administrative Body § 930.25 Failure to nominate. If nominations are not made within the time and in the manner...

7 CFR 959.28 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Failure to nominate. 959.28 Section 959.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Committee § 959.28 Failure to nominate. If nominations are not made within the time and...

7 CFR 959.28 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 959.28 Section 959.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Committee § 959.28 Failure to nominate. If nominations are not made within the time and...

7 CFR 930.25 - Failure to nominate.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Failure to nominate. 930.25 Section 930.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Administrative Body § 930.25 Failure to nominate. If nominations are not made within the time and in the manner...

7 CFR 945.26 - Failure to nominate.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 8 2012-01-01 2012-01-01 false Failure to nominate. 945.26 Section 945.26 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... § 945.26 Failure to nominate. If nominations are not made within the time and in the manner specified by...

7 CFR 930.25 - Failure to nominate.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Failure to nominate. 930.25 Section 930.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Administrative Body § 930.25 Failure to nominate. If nominations are not made within the time and in the manner...

7 CFR 945.26 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 945.26 Section 945.26 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... § 945.26 Failure to nominate. If nominations are not made within the time and in the manner specified by...

7 CFR 966.28 - Failure to nominate.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Failure to nominate. 966.28 Section 966.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Regulating Handling Committee § 966.28 Failure to nominate. If nominations are not made within the time and...

7 CFR 958.29 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 958.29 Section 958.29 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Failure to nominate. If nominations are not made within the time and in the manner specified by the...

7 CFR 930.25 - Failure to nominate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Failure to nominate. 930.25 Section 930.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Administrative Body § 930.25 Failure to nominate. If nominations are not made within the time and in the manner...

7 CFR 924.24 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 924.24 Section 924.24 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements....24 Failure to nominate. If nominations are not made within the time and in the manner prescribed in...

7 CFR 930.25 - Failure to nominate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Failure to nominate. 930.25 Section 930.25 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Administrative Body § 930.25 Failure to nominate. If nominations are not made within the time and in the manner...