Science.gov

Sample records for ground control

  1. Remotely Sensed Ground Control Points

    NASA Astrophysics Data System (ADS)

    Hummel, P.

    2016-06-01

    Accurate ground control is required to georeferenced airborne and spaceborne images. The production of ortho-photogrammetric data requires ground control that is traditionally provided as Ground Control Points (GCPs) by GNSS measurements in the field. However, it can be difficult to acquire accurate ground control points due to required turn-around time, high costs or impossible access. CompassData, Inc. a specialist in ground control, has expanded its service to deliver Remotely Sensed Ground Control Points (RSGCPs®). TerraSAR-X and TanDEM-X are two satellites with such high accuracy of their orbital positions and SAR data that RSGCPs® can be produced to a sub-meter quality depending on certain parameters and circumstances. The technology and required parameters are discussed in this paper as well as the resulting accuracies.

  2. Ground Control in Mining. Proceedings

    SciTech Connect

    Peng, S.S.

    1991-01-01

    The proceedings contain 36 papers on strata control in underground mining. Specific topics include: support pillar design, mathematical modeling of support-rock interactions, deformation of mine roadways, support recovery, roof bolt design and performance, rock burst prediction methods, detection of abandoned shafts, water influx control, rock mechanical property measurements, ground subsidence effects and forecasting, surveying techniques, and stress analyses. Papers have been processed separately for inclusion on the data base.

  3. Ground control for highwall mining

    SciTech Connect

    Zipf, R.K.; Mark, C.

    2007-09-15

    Perhaps the greatest risk to both equipment and personnel associated with highwall mining is from ground control. The two most significant ground control hazards are rock falls from highwall and equipment entrapment underground. In the central Appalachians, where the majority of highwall mining occurs in the USA, hillseams (or mountain cracks) are the most prominent structure that affects highwall stability. The article discusses measures to minimise the risk of failure associated with hillstreams. A 'stuck' or trapped highwall miner, and the ensuring retrieval or recovery operation, can be extremely disruptive to the highwall mining process. Most entrapment, are due to roof falls in the hole. The options for recovery are surface retrieval, surface excavation or underground recovery. Proper pillar design is essential to maintain highwall stability and prevent entrapments. NIOSH has developed the Analysis of Retreat Mining Pillar stability-Highwall Mining (ARMPS-HWM) computer program to help mine planners with this process. 10 figs.

  4. Coal mine ground control, second edition

    SciTech Connect

    Peng, S.S.

    1986-01-01

    This revision reflects the enormous progress made in the sciences of coal mine ground control. Many chapters are completely new, and virtually all have been substantially rewritten. Covers common ground control problems underground, rock properties and in situ stresses, geological effects and roof stability classification and investigation, roof bolting, coal pillars, ground control in longwall mining and multiple-seam mining, bumps, instrumentation, special supports and problems, and surface subsidence.

  5. Ground water. [Water pollution control

    SciTech Connect

    Costle, D.M.

    1980-09-01

    There is growing evidence that the Nation's ground water is contaminated by a variety of sources. These include unprotected industrial, municipal, and radioactive disposal sites, petroleum exploration and mining activities, agricultural operations such as insecticide spraying, high de-icing salts and others. As of March 1980, more than 8000 chemical tests have been performed on well water, with chlorinated organic solvents found most frequently. Because 100 million Americans may be threatened by unfit drinking water, EPA has developed a new ground water strategy. It will enlist the help of State and local governments who already have programs under way and it will involve broad public debate and participation.

  6. Ground Control for Emplacement Drifts for LA

    SciTech Connect

    Y. Sun

    2004-07-09

    The purpose of this calculation is to analyze the stability of repository emplacement drifts during the preclosure period, and to provide a final ground support method for emplacement drifts for the License Application (LA). The scope of the work includes determination of input parameter values and loads, selection of appropriate process and methods for the calculation, application of selected methods, such as empirical or analytical, to the calculation, development and execution of numerical models, and evaluation of results. Results from this calculation are limited to use for design of the emplacement drifts and the final ground support system installed in these drifts. The design of non-emplacement openings and their ground support systems is covered in the ''Ground Control for Non-Emplacement Drifts for LA'' (BSC 2004c).

  7. Intelligent resources for satellite ground control operations

    NASA Technical Reports Server (NTRS)

    Jones, Patricia M.

    1994-01-01

    This paper describes a cooperative approach to the design of intelligent automation and describes the Mission Operations Cooperative Assistant for NASA Goddard flight operations. The cooperative problem solving approach is being explored currently in the context of providing support for human operator teams and also in the definition of future advanced automation in ground control systems.

  8. Ground Control for Emplacement Drifts for SR

    SciTech Connect

    Y. Sun

    2000-04-07

    This analysis demonstrates that a satisfactory ground control system can be designed for the Yucca Mountain site, and provides the technical basis for the design of ground support systems to be used in repository emplacement and non-emplacement drifts. The repository ground support design was based on analytical methods using acquired computer codes, and focused on the final support systems. A literature review of case histories, including the lessons learned from the design and construction of the ESF, the studies on the seismic damages of underground openings, and the use of rock mass classification systems in the ground support design, was conducted (Sections 6.3.4 and 6.4). This review provided some basis for determining the inputs and methodologies used in this analysis. Stability of the supported and unsupported emplacement and non-emplacement drifts was evaluated in this analysis. The excavation effects (i.e., state of the stress change due to excavation), thermal effects (i.e., due to heat output from waste packages), and seismic effects (i.e., from potential earthquake events) were evaluated, and stress controlled modes of failure were examined for two in situ stress conditions (k_0=0.3 and 1.0) using rock properties representing rock mass categories of 1 and 5. Variation of rock mass units such as the non-lithophysal (Tptpmn) and lithophysal (Tptpll) was considered in the analysis. The focus was on the non-lithophysal unit because this unit appears to be relatively weaker and has much smaller joint spacing. Therefore, the drift stability and ground support needs were considered to be controlled by the design for this rock unit. The ground support systems for both emplacement and non-emplacement drifts were incorporated into the models to assess their performance under in situ, thermal, and seismic loading conditions. Both continuum and discontinuum modeling approaches were employed in the analyses of the rock mass behavior and in the evaluation of the

  9. Limits to ground control in autonomous spacecraft

    NASA Technical Reports Server (NTRS)

    Wan, Alfred D. M.; Braspenning, Peter J.; Vreeswijk, Gerrard A. W.

    1995-01-01

    In this paper the autonomy concept used by ESA and NASA is critically evaluated. Moreover, a more proper ground control/spacecraft organizational structure is proposed on the basis of a new, more elaborated concept of autonomy. In an extended theoretical discussion its definitional properties and functionalities are established. The rather basic property of adaptivity leads to the categorization of behaviour into the modes of satisfaction and avoidance behaviour. However, the autonomy property with the most profound consequences is goal-robustness. The mechanism that implements goal-robustness tests newly generated goals and externally received goals on consistency with high-level goals. If goals appear not to be good instantiations or more acceptable replacements of existing goals, they are rejected. This means that ground control has to cooperate with the spacecraft instead of (intermittently) commanding it.

  10. Coal mine ground control. 3rd ed.

    SciTech Connect

    Peng, S.S.

    2008-09-15

    The third edition not only completely revises and updates the original subject areas, but also is broadened to include a number of new topics such as high horizontal stresses, computer modeling, and highwall stability. The subject areas covered in this book define the current field of coal mine ground control, except for the recently emerging topic of mine seals and some conventional subjects such as coal/rock cutting and impoundment dams. It contains 1,134 references from all published sources, and archived since 1876.

  11. Emissions control for ground power gas turbines

    NASA Technical Reports Server (NTRS)

    Rudney, R. A.; Priem, R. J.; Juhasz, A. J.; Anderson, D. N.; Mroz, T. S.; Mularz, E. J.

    1977-01-01

    The similarities and differences of emissions reduction technology for aircraft and ground power gas turbines is described. The capability of this technology to reduce ground power emissions to meet existing and proposed emissions standards is presented and discussed. Those areas where the developing aircraft gas turbine technology may have direct application to ground power and those areas where the needed technology may be unique to the ground power mission are pointed out. Emissions reduction technology varying from simple combustor modifications to the use of advanced combustor concepts, such as catalysis, is described and discussed.

  12. Proceedings, 25th international conference on ground control in mining

    SciTech Connect

    Peng, S.S.; Mark, C.; Finfinger, G.; Tadolini, S.; Wahab Khair, A.; Heasley, K.; Luo, Y.

    2006-07-01

    Topics covered include: computer and physical modelling; geology in ground control; geophysics in ground control; ground control; impoundments stability; longwall gateroad support design; longwall operations; longwall shields and standing supports; mine design; multiple-seam mining interactions; pillar and pillar extraction; roof bolting; roof bolting - resin; and subsidence. Most of the topics include a retrospective paper which summarises the progress of the subject field during the past 25 years.

  13. 24 CFR 3285.204 - Ground moisture control.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Ground moisture control. 3285.204... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Site Preparation § 3285.204 Ground... materials, a vapor retarder must be installed to cover the ground under the home, unless the home...

  14. 24 CFR 3285.204 - Ground moisture control.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Ground moisture control. 3285.204... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Site Preparation § 3285.204 Ground... materials, a vapor retarder must be installed to cover the ground under the home, unless the home...

  15. 24 CFR 3285.204 - Ground moisture control.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Ground moisture control. 3285.204... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Site Preparation § 3285.204 Ground... materials, a vapor retarder must be installed to cover the ground under the home, unless the home...

  16. 24 CFR 3285.204 - Ground moisture control.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Ground moisture control. 3285.204... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Site Preparation § 3285.204 Ground... materials, a vapor retarder must be installed to cover the ground under the home, unless the home...

  17. 24 CFR 3285.204 - Ground moisture control.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Ground moisture control. 3285.204... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Site Preparation § 3285.204 Ground... materials, a vapor retarder must be installed to cover the ground under the home, unless the home...

  18. Onboard utilization of ground control points for image correction. Volume 3: Ground control point simulation software design

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The software developed to simulate the ground control point navigation system is described. The Ground Control Point Simulation Program (GCPSIM) is designed as an analysis tool to predict the performance of the navigation system. The system consists of two star trackers, a global positioning system receiver, a gyro package, and a landmark tracker.

  19. Frozen Ground Controls on Hydrological Processes

    NASA Astrophysics Data System (ADS)

    Hinzman, L. D.; Kane, D. L.; Woo, M. K.

    2015-12-01

    Frozen ground establishes a unique discipline of hydrologic science where the hydrologic regime is intimately coupled with the thermal regime to the extent that one may not be completely understood without correct characterization of the other. In permafrost regions, material properties may change drastically on a scale of centimeters to meters, particularly in the vertical dimension due to distinct changes in soil and thermal characteristics. Properties may vary just as dramatically in the horizontal dimension across the boundary of discontinuous permafrost. Although the spatial extent of permafrost changes on relatively slow time scales in response to disturbance or a changing climate, this too introduces an added level of complexity. Permafrost may nearly eliminate the interactions between near-surface and sub-permafrost aquifers, which in essence defines the hydrologic response of every watershed that is directly influenced by permafrost. Even though the principles governing water movement in permafrost areas are the same as those in more temperate regions, interactions of extremes in climate and the land surface characteristics render permafrost hydrology different from the hydrology of temperate latitudes. Ice-rich permafrost prevents deep percolation of rainfall or snowmelt water, often maintaining a moist to saturated active layer above the permafrost table. Most hydrologic activities are confined above-ground or in the thin active layer, which supplies summer moisture for baseflow and/or plant transpiration. Limited storage capacity of the thawed active layer does not support extended baseflow in a stream, though the proportion of baseflow increases as the percentage of permafrost extent decreases. In areas where permafrost is discontinuous or where it has thawed substantially near the surface, local hydrology may display a markedly different character as there are stronger exchanges between the surface water and the ground water system, or water may drain

  20. Grounding cognitive control in associative learning.

    PubMed

    Abrahamse, Elger; Braem, Senne; Notebaert, Wim; Verguts, Tom

    2016-07-01

    Cognitive control covers a broad range of cognitive functions, but its research and theories typically remain tied to a single domain. Here we outline and review an associative learning perspective on cognitive control in which control emerges from associative networks containing perceptual, motor, and goal representations. Our review identifies 3 trending research themes that are shared between the domains of conflict adaptation, task switching, response inhibition, and attentional control: Cognitive control is context-specific, can operate in the absence of awareness, and is modulated by reward. As these research themes can be envisaged as key characteristics of learning, we propose that their joint emergence across domains is not coincidental but rather reflects a (latent) growth of interest in learning-based control. Associative learning has the potential for providing broad-scaled integration to cognitive control theory, and offers a promising avenue for understanding cognitive control as a self-regulating system without postulating an ill-defined set of homunculi. We discuss novel predictions, theoretical implications, and immediate challenges that accompany an associative learning perspective on cognitive control. (PsycINFO Database Record PMID:27148628

  1. A New Definition for Ground Control

    NASA Technical Reports Server (NTRS)

    2002-01-01

    LandForm(R) VisualFlight(R) blends the power of a geographic information system with the speed of a flight simulator to transform a user's desktop computer into a "virtual cockpit." The software product, which is fully compatible with all Microsoft(R) Windows(R) operating systems, provides distributed, real-time three-dimensional flight visualization over a host of networks. From a desktop, a user can immediately obtain a cockpit view, a chase-plane view, or an airborne tracker view. A customizable display also allows the user to overlay various flight parameters, including latitude, longitude, altitude, pitch, roll, and heading information. Rapid Imaging Software sought assistance from NASA, and the VisualFlight technology came to fruition under a Phase II SBIR contract with Johnson Space Center in 1998. Three years later, on December 13, 2001, Ken Ham successfully flew NASA's X-38 spacecraft from a remote, ground-based cockpit using LandForm VisualFlight as part of his primary situation awareness display in a flight test at Edwards Air Force Base, California.

  2. Active control landing gear for ground loads alleviation

    NASA Technical Reports Server (NTRS)

    Mcgehee, J. R.

    1985-01-01

    An active landing gear has been created by connecting the hydraulic piston in an oleo strut to a hydraulic supply. A controller modulates the pressure in the oleo to achieve the desired dynamic characteristics. Tests on ground rigs (documented by a film) have demonstrated the successful alleviation of induced structural ground loads and the next step will be a flight test using a fighter aircraft.

  3. Configurable technology development for reusable control and monitor ground systems

    NASA Technical Reports Server (NTRS)

    Uhrlaub, David R.

    1994-01-01

    The control monitor unit (CMU) uses configurable software technology for real-time mission command and control, telemetry processing, simulation, data acquisition, data archiving, and ground operations automation. The base technology is currently planned for the following control and monitor systems: portable Space Station checkout systems; ecological life support systems; Space Station logistics carrier system; and the ground system of the Delta Clipper (SX-2) in the Single-Stage Rocket Technology program. The CMU makes extensive use of commercial technology to increase capability and reduce development and life-cycle costs. The concepts and technology are being developed by McDonnell Douglas Space and Defense Systems for the Real-Time Systems Laboratory at NASA's Kennedy Space Center under the Payload Ground Operations Contract. A second function of the Real-Time Systems Laboratory is development and utilization of advanced software development practices.

  4. The ACTS NASA Ground Station/Master Control Station

    NASA Technical Reports Server (NTRS)

    Meadows, David N.

    1992-01-01

    Two of the major components of the ACTS Ground Segment are the NASA Ground Station (NGS) and the Master Control Station (MCS), colocated at the NASA Lewis Research Center. Essentially, the NGS provides the communications links by which the MCS performs its various network control and monitoring functions. The NGS also provides telecommunications links capable of transmission/reception of up to approximately 70 Mbit/s of digital telephonic traffic. Operating as a system, the entire complex of equipment is referred to as the NGS/MCS. This paper provides an 'as-built' description of the NGS/MCS as a system.

  5. Ground controlled robotic assembly operations for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Parrish, Joseph C.

    1991-01-01

    A number of dextrous robotic systems and associated positioning and transportation devices are available on Space Station Freedom (SSF) to perform assembly tasks that would otherwise need to be performed by extravehicular activity (EVA) crewmembers. The currently planned operating mode for these robotic systems during the assembly phase is teleoperation by intravehicular activity (IVA) crewmembers. While this operating mode is less hazardous and expensive than manned EVA operations, and has insignificant control loop time delays, the amount of IVA time available to support telerobotic operations is much less than the anticipated requirements. Some alternative is needed to allow the robotic systems to perform useful tasks without exhausting the available IVA resources; ground control is one such alternative. The issues associated with ground control of SSF robotic systems to alleviate onboard crew time availability constraints are investigated. Key technical issues include the effect of communication time delays, the need for safe, reliable execution of remote operations, and required modifications to the SSF ground and flight system architecture. Time delay compensation techniques such as predictive displays and world model-based force reflection are addressed and collision detection and avoidance strategies to ensure the safety of the on-orbit crew, Orbiter, and SSF are described. Although more time consuming and difficult than IVA controlled teleoperations or manned EVA, ground controlled telerobotic operations offer significant benefits during the SSF assembly phase, and should be considered in assembly planning activities.

  6. Control of ground-borne noise and vibration

    NASA Astrophysics Data System (ADS)

    Wilson, G. P.; Saurenman, H. J.; Nelson, J. T.

    1983-03-01

    Ground-borne noise and vibration created by train operations is one of the major environmental problems faced by rail transit systems. In the past 10-20 years there have been a number of developments in the control and prediction of ground-borne noise and vibration although it is evident that further research is needed. In this paper the focus is on two methods of controlling the vibration radiated by the transit structure. First is the use of floating slab trackbeds, a method that has proven to be very effective at reducing vibration at frequencies above the resonance frequency of the floating slab system. Second is to modify the design of transit car bogies such that the wheel/rail forces are reduced. Although this method is still in the exploratory phase it has been shown that proper design of the bogie suspension can significantly reduce the levels of ground-borne noise and vibration.

  7. VIEW OF CONTROL PANEL (RIGHT) AT THE GROUND FLOOR LEVEL ...

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

    VIEW OF CONTROL PANEL (RIGHT) AT THE GROUND FLOOR LEVEL AND SIDE OF THE MISSILE TUBE (FOREGROUND). VIEW FACING EAST - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  8. Ground vehicle control at NIST: From teleoperation to autonomy

    NASA Technical Reports Server (NTRS)

    Murphy, Karl N.; Juberts, Maris; Legowik, Steven A.; Nashman, Marilyn; Schneiderman, Henry; Scott, Harry A.; Szabo, Sandor

    1994-01-01

    NIST is applying their Real-time Control System (RCS) methodology for control of ground vehicles for both the U.S. Army Researh Lab, as part of the DOD's Unmanned Ground Vehicles program, and for the Department of Transportation's Intelligent Vehicle/Highway Systems (IVHS) program. The actuated vehicle, a military HMMWV, has motors for steering, brake, throttle, etc. and sensors for the dashboard gauges. For military operations, the vehicle has two modes of operation: a teleoperation mode--where an operator remotely controls the vehicle over an RF communications network; and a semi-autonomous mode called retro-traverse--where the control system uses an inertial navigation system to steer the vehicle along a prerecorded path. For the IVHS work, intelligent vision processing elements replace the human teleoperator to achieve autonomous, visually guided road following.

  9. 7th international conference on ground control in mining

    SciTech Connect

    Peng, S.S.

    1988-01-01

    These proceedings contain 38 papers describing strata control, rock mechanics, and ground subsidence, especially in longwall mining. Other mining methods discussed include room and pillar mining, retreat mining, caving mining, and auger underground mining. Design, performance, and mathematical models of support pillars and other types of strata support systems are described. Most of the studies were done in US coal mines, but several papers describing strata control in India, China, South Africa, and Taiwan are included. All papers have been indexed separately.

  10. Controls, astrophysics, and structures experiment in space ground test facility

    NASA Technical Reports Server (NTRS)

    Bukley, Angelia P.; Jones, Victoria L.

    1992-01-01

    This paper describes the initial configuration of the NASA Marshall Space Flight Center (MSFC) Controls/Structures Interaction Advanced Development Facility (CSI ADF), which is a ground test facility (GTF) for the proposed Controls, Astrophysics, and Structures Experiment in Space (CASES). The laboratory has been developed for the purpose of implementing, testing, and evaluating CSI modeling, control system design, failure analysis, and system identification techniques on a representative large space structure. The facility has been configured to represent as closely as possible an actual flight article.

  11. 30 CFR 77.1004 - Ground control; inspection and maintenance; general.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Ground control; inspection and maintenance... OF UNDERGROUND COAL MINES Ground Control § 77.1004 Ground control; inspection and maintenance... unsafe ground conditions shall be corrected promptly, or the area shall be posted....

  12. 30 CFR 77.1004 - Ground control; inspection and maintenance; general.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Ground control; inspection and maintenance... OF UNDERGROUND COAL MINES Ground Control § 77.1004 Ground control; inspection and maintenance... unsafe ground conditions shall be corrected promptly, or the area shall be posted....

  13. 30 CFR 77.1004 - Ground control; inspection and maintenance; general.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Ground control; inspection and maintenance... OF UNDERGROUND COAL MINES Ground Control § 77.1004 Ground control; inspection and maintenance... unsafe ground conditions shall be corrected promptly, or the area shall be posted....

  14. 30 CFR 77.1004 - Ground control; inspection and maintenance; general.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Ground control; inspection and maintenance... OF UNDERGROUND COAL MINES Ground Control § 77.1004 Ground control; inspection and maintenance... unsafe ground conditions shall be corrected promptly, or the area shall be posted....

  15. 30 CFR 77.1004 - Ground control; inspection and maintenance; general.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Ground control; inspection and maintenance... OF UNDERGROUND COAL MINES Ground Control § 77.1004 Ground control; inspection and maintenance... unsafe ground conditions shall be corrected promptly, or the area shall be posted....

  16. Recent Developments in Ground-Borne Noise and Vibration Control

    NASA Astrophysics Data System (ADS)

    Nelson, J. T.

    1996-05-01

    Vibration control provisions available to the transit designer include (among others) precision straightened rail, ballast mats, floating slabs and very soft direct fixation fasteners, in addition to rail grinding, wheel truing, and continuous welded rail. Recently, the Los Angeles Metro has developed specifications for a soft resilient direct fixation fastener to fit the same base dimensions as the standard direct fixation fastener. In San Francisco, low resonance frequency (8 Hz) floating slabs have been constructed to mitigate predicted ground vibration impacts at nearby residential structures. In Atlanta, low resonance frequency loading slabs have been constructed to maintain a low vibration environment in a medical building planned to be built over the subway structure. In Portland and Pasadena, ballast mats have been recommended to control light rail transit ground vibration impacts on housing located at typically 35 feet from the alignment. Each of these provisions are briefly described in view of recent applications at U.S. transit systems.

  17. Coherent Control of Ground State NaK Molecules

    NASA Astrophysics Data System (ADS)

    Yan, Zoe; Park, Jee Woo; Loh, Huanqian; Will, Sebastian; Zwierlein, Martin

    2016-05-01

    Ultracold dipolar molecules exhibit anisotropic, tunable, long-range interactions, making them attractive for the study of novel states of matter and quantum information processing. We demonstrate the creation and control of 23 Na40 K molecules in their rovibronic and hyperfine ground state. By applying microwaves, we drive coherent Rabi oscillations of spin-polarized molecules between the rotational ground state (J=0) and J=1. The control afforded by microwave manipulation allows us to pursue engineered dipolar interactions via microwave dressing. By driving a two-photon transition, we are also able to observe Ramsey fringes between different J=0 hyperfine states, with coherence times as long as 0.5s. The realization of long coherence times between different molecular states is crucial for applications in quantum information processing. NSF, AFOSR- MURI, Alfred P. Sloan Foundation, DARPA-OLE

  18. Ground vibration test of the laminar flow control JStar airplane

    NASA Technical Reports Server (NTRS)

    Kehoe, M. W.; Cazier, F. W., Jr.; Ellison, J. F.

    1985-01-01

    A ground vibration test was conducted on a Lockheed JetStar airplane that had been modified for the purpose of conducting laminar flow control experiments. The test was performed prior to initial flight flutter tests. Both sine-dwell and single-point-random excitation methods were used. The data presented include frequency response functions and a comparison of mode frequencies and mode shapes from both methods.

  19. ALLY: An operator's associate for satellite ground control systems

    NASA Technical Reports Server (NTRS)

    Bushman, J. B.; Mitchell, Christine M.; Jones, P. M.; Rubin, K. S.

    1991-01-01

    The key characteristics of an intelligent advisory system is explored. A central feature is that human-machine cooperation should be based on a metaphor of human-to-human cooperation. ALLY, a computer-based operator's associate which is based on a preliminary theory of human-to-human cooperation, is discussed. ALLY assists the operator in carrying out the supervisory control functions for a simulated NASA ground control system. Experimental evaluation of ALLY indicates that operators using ALLY performed at least as well as they did when using a human associate and in some cases even better.

  20. Study to eliminate ground resonance using active controls

    NASA Technical Reports Server (NTRS)

    Straub, F. K.

    1984-01-01

    The effectiveness of active control blade feathering in increasing rotor body damping and the possibility to eliminate ground resonance instabilities were investigated. An analytical model representing rotor flapping and lead-lag degrees of freedom and body pitch, roll, longitudinal and lateral motion is developed. Active control blade feathering is implemented as state variable feedback through a conventional swashplate. The influence of various feedback states, feedback gain, and weighting between the cyclic controls is studied through stability and response analyses. It is shown that blade cyclic inplane motion, roll rate and roll acceleration feedback can add considerable damping to the system and eliminate ground resonance instabilities, which the feedback phase is also a powerful parameter, if chosen properly, it maximizes augmentation of the inherent regressing lag mode damping. It is shown that rotor configuration parameters, like blade root hinge offset, flapping stiffness, and precone considerably influence the control effectiveness. It is found that active control is particularly powerful for hingeless and bearingless rotor systems.

  1. Ground Operations Autonomous Control and Integrated Health Management

    NASA Technical Reports Server (NTRS)

    Daniels, James

    2014-01-01

    The Ground Operations Autonomous Control and Integrated Health Management plays a key role for future ground operations at NASA. The software that is integrated into this system is called G2 2011 Gensym. The purpose of this report is to describe the Ground Operations Autonomous Control and Integrated Health Management with the use of the G2 Gensym software and the G2 NASA toolkit for Integrated System Health Management (ISHM) which is a Computer Software Configuration Item (CSCI). The decision rationale for the use of the G2 platform is to develop a modular capability for ISHM and AC. Toolkit modules include knowledge bases that are generic and can be applied in any application domain module. That way, there's a maximization of reusability, maintainability, and systematic evolution, portability, and scalability. Engine modules are generic, while application modules represent the domain model of a specific application. Furthermore, the NASA toolkit, developed since 2006 (a set of modules), makes it possible to create application domain models quickly, using pre-defined objects that include sensors and components libraries for typical fluid, electrical, and mechanical systems.

  2. Factors controlling tungsten concentrations in ground water, Carson Desert, Nevada

    USGS Publications Warehouse

    Seiler, R.L.; Stollenwerk, K.G.; Garbarino, J.R.

    2005-01-01

    An investigation of a childhood leukemia cluster by US Centers for Disease Control and Prevention revealed that residents of the Carson Desert, Nevada, are exposed to high levels of W and this prompted an investigation of W in aquifers used as drinking water sources. Tungsten concentrations in 100 ground water samples from all aquifers used as drinking water sources in the area ranged from 0.27 to 742 ??g/l. Ground water in which W concentrations exceed 50 ??g/l principally occurs SE of Fallon in a geothermal area. The principal sources of W in ground water are natural and include erosion of W-bearing mineral deposits in the Carson River watershed upstream of Fallon, and, possibly, upwelling geothermal waters. Ground water in the Fallon area is strongly reducing and reductive dissolution of Fe and Mn oxyhydroxides may be releasing W; however, direct evidence that the metal oxides contain W is not available. Although W and Cl concentrations in the Carson River, a lake, and water from many wells, appear to be controlled by evaporative concentration, evaporation alone cannot explain the elevated W concentrations found in water from some of the wells. Concentrations of W exceeding 50 ??g/l are exclusively associated with Na-HCO3 and Na-Cl water types and pH > 8.0; in these waters, geochemical modeling indicates that W exhibits <10% adsorption. Tungsten concentrations are strongly and positively correlated with As, B, F, and P, indicating either common sources or common processes controlling their concentrations. Geochemical modeling indicates W concentrations are consistent with pH-controlled adsorption of W. The geochemical model PHREEQC was used to calculate IAP values, which were compared with published Ksp values for primary W minerals. FeWO4, MnWO4, Na2WO4, and MgWO4 were undersaturated and CaWO4 and SrWO 4 were approaching saturation. These conclusions are tentative because of uncertainty in the thermodynamic data. The similar behavior of As and W observed in

  3. SILEX ground segment control facilities and flight operations

    NASA Astrophysics Data System (ADS)

    Demelenne, Benoit; Tolker-Nielsen, Toni; Guillen, Jean-Claude

    1999-04-01

    The European Space Agency is going to conduct an inter orbit link experiment which will connect a low Earth orbiting satellite and a Geostationary satellite via optical terminals. This experiment has been called SILEX (Semiconductor Inter satellite Link Experiment). Two payloads have been built. One called PASTEL (PASsager de TELecommunication) has been embarked on the French Earth observation satellite SPOT4 which has been launched successfully in March 1998. The future European experimental data relay satellite ARTEMIS (Advanced Relay and TEchnology MISsion), which will route the data to ground, will carry the OPALE terminal (Optical Payload Experiment). The European Space Agency is responsible for the operation of both terminals. Due to the complexity and experimental character of this new optical technology, the development, preparation and validation of the ground segment control facilities required a long series of technical and operational qualification tests. This paper is presenting the operations concept and the early results of the PASTEL in orbit operations.

  4. Control of Asymmetric Cell Divisions during Root Ground Tissue Maturation

    PubMed Central

    Choi, Ji Won; Lim, Jun

    2016-01-01

    Controlling the production of diverse cell/tissue types is essential for the development of multicellular organisms such as animals and plants. The Arabidopsis thaliana root, which contains distinct cells/tissues along longitudinal and radial axes, has served as an elegant model to investigate how genetic programs and environmental signals interact to produce different cell/tissue types. In the root, a series of asymmetric cell divisions (ACDs) give rise to three ground tissue layers at maturity (endodermis, middle cortex, and cortex). Because the middle cortex is formed by a periclinal (parallel to the axis) ACD of the endodermis around 7 to 14 days post-germination, middle cortex formation is used as a parameter to assess maturation of the root ground tissue. Molecular, genetic, and physiological studies have revealed that the control of the timing and extent of middle cortex formation during root maturation relies on the interaction of plant hormones and transcription factors. In particular, abscisic acid and gibberellin act synergistically to regulate the timing and extent of middle cortex formation, unlike their typical antagonism. The SHORT-ROOT, SCARECROW, SCARECROW-LIKE 3, and DELLA transcription factors, all of which belong to the plant-specific GRAS family, play key roles in the regulation of middle cortex formation. Recently, two additional transcription factors, SEUSS and GA- AND ABA-RESPONSIVE ZINC FINGER, have also been characterized during ground tissue maturation. In this review, we provide a detailed account of the regulatory networks that control the timing and extent of middle cortex formation during post-embryonic root development. PMID:27306644

  5. Automatic Scheduling and Planning (ASAP) in future ground control systems

    NASA Technical Reports Server (NTRS)

    Matlin, Sam

    1988-01-01

    This report describes two complementary approaches to the problem of space mission planning and scheduling. The first is an Expert System or Knowledge-Based System for automatically resolving most of the activity conflicts in a candidate plan. The second is an Interactive Graphics Decision Aid to assist the operator in manually resolving the residual conflicts which are beyond the scope of the Expert System. The two system designs are consistent with future ground control station activity requirements, support activity timing constraints, resource limits and activity priority guidelines.

  6. Ground control failures. A pictorial view of case studies

    SciTech Connect

    Peng, S.S.

    2007-07-01

    The book shows, in pictorial views, many forms and/or stages of types of failures in mines, for instance, cutter, roof falls, and cribs. In each case, the year of occurrence is stated in the beginning so that the environment or technological background under which it occurred are reflected. The narrative than begins with the mining and geological conditions, followed by a description of the ground control problems and recommended solutions and results, if any. The sections cover failure of pillars, roof falls, longwall, roof bolting, multiple-seam mining, floor heave, longwall, flooding and weathering of coal, old workings, and shortwall and thin-seam plow longwall.

  7. Automatic ground control point recognition with parallel associative memory

    NASA Technical Reports Server (NTRS)

    Al-Tahir, Raid; Toth, Charles K.; Schenck, Anton F.

    1990-01-01

    The basic principle of the associative memory is to match the unknown input pattern against a stored training set, and responding with the 'closest match' and the corresponding label. Generally, an associative memory system requires two preparatory steps: selecting attributes of the pattern class, and training the system by associating patterns with labels. Experimental results gained from using Parallel Associative Memory are presented. The primary concern is an automatic search for ground control points in aerial photographs. Synthetic patterns are tested followed by real data. The results are encouraging as a relatively high level of correct matches is reached.

  8. The 18th Annual Intelligent Ground Vehicle Competition: trends and influences for intelligent ground vehicle control

    NASA Astrophysics Data System (ADS)

    Theisen, Bernard L.; Frederick, Philip; Smuda, William

    2011-01-01

    The Intelligent Ground Vehicle Competition (IGVC) is one of four, unmanned systems, student competitions that were founded by the Association for Unmanned Vehicle Systems International (AUVSI). The IGVC is a multidisciplinary exercise in product realization that challenges college engineering student teams to integrate advanced control theory, machine vision, vehicular electronics and mobile platform fundamentals to design and build an unmanned system. Teams from around the world focus on developing a suite of dual-use technologies to equip ground vehicles of the future with intelligent driving capabilities. Over the past 18 years, the competition has challenged undergraduate, graduate and Ph.D. students with real world applications in intelligent transportation systems, the military and manufacturing automation. To date, teams from over 75 universities and colleges have participated. This paper describes some of the applications of the technologies required by this competition and discusses the educational benefits. The primary goal of the IGVC is to advance engineering education in intelligent vehicles and related technologies. The employment and professional networking opportunities created for students and industrial sponsors through a series of technical events over the four-day competition are highlighted. Finally, an assessment of the competition based on participation is presented.

  9. Lessons learned on the Ground Test Accelerator control system

    SciTech Connect

    Kozubal, A.J.; Weiss, R.E.

    1994-09-01

    When we initiated the control system design for the Ground Test Accelerator (GTA), we envisioned a system that would be flexible enough to handle the changing requirements of an experimental project. This control system would use a developers` toolkit to reduce the cost and time to develop applications for GTA, and through the use of open standards, the system would accommodate unforeseen requirements as they arose. Furthermore, we would attempt to demonstrate on GTA a level of automation far beyond that achieved by existing accelerator control systems. How well did we achieve these goals? What were the stumbling blocks to deploying the control system, and what assumptions did we make about requirements that turned out to be incorrect? In this paper we look at the process of developing a control system that evolved into what is now the ``Experimental Physics and Industrial Control System`` (EPICS). Also, we assess the impact of this system on the GTA project, as well as the impact of GTA on EPICS. The lessons learned on GTA will be valuable for future projects.

  10. De-tabooing dying control - a grounded theory study

    PubMed Central

    2013-01-01

    Background Dying is inescapable yet remains a neglected issue in modern health care. The research question in this study was “what is going on in the field of dying today?” What emerged was to eventually present a grounded theory of control of dying focusing specifically on how people react in relation to issues about euthanasia and physician-assisted suicide (PAS). Methods Classic grounded theory was used to analyze interviews with 55 laypersons and health care professionals in North America and Europe, surveys on attitudes to PAS among physicians and the Swedish general public, and scientific literature, North American discussion forum websites, and news sites. Results Open awareness of the nature and timing of a patient’s death became common in health care during the 1960s in the Western world. Open dying awareness contexts can be seen as the start of a weakening of a taboo towards controlled dying called de-tabooing. The growth of the hospice movement and palliative care, but also the legalization of euthanasia and PAS in the Benelux countries, and PAS in Montana, Oregon and Washington further represents de-tabooing dying control. An attitude positioning between the taboo of dying control and a growing taboo against questioning patient autonomy and self-determination called de-paternalizing is another aspect of de-tabooing. When confronted with a taboo, people first react emotionally based on “gut feelings” - emotional positioning. This is followed by reasoning and label wrestling using euphemisms and dysphemisms - reflective positioning. Rarely is de-tabooing unconditional but enabled by stipulated positioning as in soft laws (palliative care guidelines) and hard laws (euthanasia/PAS legislation). From a global perspective three shapes of dying control emerge. First, suboptimal palliative care in closed awareness contexts seen in Asian, Islamic and Latin cultures, called closed dying. Second, palliative care and sedation therapy, but not euthanasia

  11. Feasibility of Automated Adaptive GCA (Ground Controlled Approach) Controller Training System.

    ERIC Educational Resources Information Center

    Feuge, Robert L.; And Others

    An analysis of the conceptual feasibility of using automatic speech recognition and understanding technology in the design of an advanced training system was conducted. The analysis specifically explored application to Ground Controlled Approach (GCA) controller training. A systems engineering approach was followed to determine the feasibility of…

  12. Path planning and Ground Control Station simulator for UAV

    NASA Astrophysics Data System (ADS)

    Ajami, A.; Balmat, J.; Gauthier, J.-P.; Maillot, T.

    In this paper we present a Universal and Interoperable Ground Control Station (UIGCS) simulator for fixed and rotary wing Unmanned Aerial Vehicles (UAVs), and all types of payloads. One of the major constraints is to operate and manage multiple legacy and future UAVs, taking into account the compliance with NATO Combined/Joint Services Operational Environment (STANAG 4586). Another purpose of the station is to assign the UAV a certain degree of autonomy, via autonomous planification/replanification strategies. The paper is organized as follows. In Section 2, we describe the non-linear models of the fixed and rotary wing UAVs that we use in the simulator. In Section 3, we describe the simulator architecture, which is based upon interacting modules programmed independently. This simulator is linked with an open source flight simulator, to simulate the video flow and the moving target in 3D. To conclude this part, we tackle briefly the problem of the Matlab/Simulink software connection (used to model the UAV's dynamic) with the simulation of the virtual environment. Section 5 deals with the control module of a flight path of the UAV. The control system is divided into four distinct hierarchical layers: flight path, navigation controller, autopilot and flight control surfaces controller. In the Section 6, we focus on the trajectory planification/replanification question for fixed wing UAV. Indeed, one of the goals of this work is to increase the autonomy of the UAV. We propose two types of algorithms, based upon 1) the methods of the tangent and 2) an original Lyapunov-type method. These algorithms allow either to join a fixed pattern or to track a moving target. Finally, Section 7 presents simulation results obtained on our simulator, concerning a rather complicated scenario of mission.

  13. Developing satellite ground control software through graphical models

    NASA Technical Reports Server (NTRS)

    Bailin, Sidney; Henderson, Scott; Paterra, Frank; Truszkowski, Walt

    1992-01-01

    This paper discusses a program of investigation into software development as graphical modeling. The goal of this work is a more efficient development and maintenance process for the ground-based software that controls unmanned scientific satellites launched by NASA. The main hypothesis of the program is that modeling of the spacecraft and its subsystems, and reasoning about such models, can--and should--form the key activities of software development; by using such models as inputs, the generation of code to perform various functions (such as simulation and diagnostics of spacecraft components) can be automated. Moreover, we contend that automation can provide significant support for reasoning about the software system at the diagram level.

  14. Next Generation GPS Ground Control Segment (OCX) Navigation Design

    NASA Technical Reports Server (NTRS)

    Bertiger, Willy; Bar-Sever, Yoaz; Harvey, Nate; Miller, Kevin; Romans, Larry; Weiss, Jan; Doyle, Larry; Solorzano, Tara; Petzinger, John; Stell, Al

    2010-01-01

    In February 2010, a Raytheon-led team was selected by The Air Force to develop, implement, and operate the next generation GPS ground control segment (OCX). To meet and exceed the demanding OCX navigation performance requirements, the Raytheon team partnered with ITT (Navigation lead) and JPL to adapt major elements of JPL's navigation technology, proven in the operations of the Global Differential GPS (GDGPS) System. Key design goals for the navigation subsystem include accurate ephemeris and clock accuracy (user range error), ease of model upgrades, and a smooth and safe transition from the legacy system to OCX.We will describe key elements of the innovative architecture of the OCX navigation subsystem,and demonstrate the anticipated performance of the system through high fidelity simulations withactual GPS measurements.

  15. Active Thermal Control Experiments for LISA Ground Verification Testing

    NASA Astrophysics Data System (ADS)

    Higuchi, Sei; DeBra, Daniel B.

    2006-11-01

    The primary mission goal of LISA is detecting gravitational waves. LISA uses laser metrology to measure the distance between proof masses in three identical spacecrafts. The total acceleration disturbance to each proof mass is required to be below 3 × 10-15 m/s2√Hz . Optical path length variations on each optical bench must be kept below 40 pm/√Hz over 1 Hz to 0.1 mHz. Thermal variations due to, for example, solar radiation or temperature gradients across the proof mass housing will distort the spacecraft causing changes in the mass attraction and sensor location. We have developed a thermal control system developed for the LISA gravitational reference sensor (GRS) ground verification testing which provides thermal stability better than 1 mK/√Hz to f < 1 mHz and which by extension is suitable for in-flight thermal control for the LISA spacecraft to compensate solar irradiation. Thermally stable environment is very demanded for LISA performance verification. In a lab environment specifications can be met with considerable amount of insulation and thermal mass. For spacecraft, the very limited thermal mass calls for an active control system which can meet disturbance rejection and stability requirements simultaneously in the presence of long time delay. A simple proportional plus integral control law presently provides approximately 1 mK/√Hz of thermal stability for over 80 hours. Continuing development of a model predictive feed-forward algorithm will extend performance to below 1 mK/√Hz at f < 1 mHz and lower.

  16. Ground Operations Autonomous Control and Integrated Health Management

    NASA Technical Reports Server (NTRS)

    Figueroa, Fernando; Walker, Mark; Wilkins, Kim; Johnson, Robert; Sass, Jared; Youney, Justin

    2014-01-01

    An intelligent autonomous control capability has been developed and is currently being validated in ground cryogenic fluid management operations. The capability embodies a physical architecture consistent with typical launch infrastructure and control systems, augmented by a higher level autonomous control (AC) system enabled to make knowledge-based decisions. The AC system is supported by an integrated system health management (ISHM) capability that detects anomalies, diagnoses causes, determines effects, and could predict future anomalies. AC is implemented using the concept of programmed sequences that could be considered to be building blocks of more generic mission plans. A sequence is a series of steps, and each executes actions once conditions for the step are met (e.g. desired temperatures or fluid state are achieved). For autonomous capability, conditions must consider also health management outcomes, as they will determine whether or not an action is executed, or how an action may be executed, or if an alternative action is executed instead. Aside from health, higher level objectives can also drive how a mission is carried out. The capability was developed using the G2 software environment (www.gensym.com) augmented by a NASA Toolkit that significantly shortens time to deployment. G2 is a commercial product to develop intelligent applications. It is fully object oriented. The core of the capability is a Domain Model of the system where all elements of the system are represented as objects (sensors, instruments, components, pipes, etc.). Reasoning and decision making can be done with all elements in the domain model. The toolkit also enables implementation of failure modes and effects analysis (FMEA), which are represented as root cause trees. FMEA's are programmed graphically, they are reusable, as they address generic FMEA referring to classes of subsystems or objects and their functional relationships. User interfaces for integrated awareness by

  17. Active control of shocks and sonic boom ground signal

    NASA Astrophysics Data System (ADS)

    Yagiz, Bedri

    The manipulation of a flow field to obtain a desired change is a much heightened subject. Active flow control has been the subject of the major research areas in fluid mechanics for the past two decades. It offers new solutions for mitigation of shock strength, sonic boom alleviation, drag minimization, reducing blade-vortex interaction noise in helicopters, stall control and the performance maximization of existing designs to meet the increasing requirements of the aircraft industries. Despite the wide variety of the potential applications of active flow control, the majority of studies have been performed at subsonic speeds. The active flow control cases were investigated in transonic speed in this study. Although the active flow control provides significant improvements, the sensibility of aerodynamic performance to design parameters makes it a nontrivial and expensive problem, so the designer has to optimize a number of different parameters. For the purpose of gaining understanding of the active flow control concepts, an automated optimization cycle process was generated. Also, the optimization cycle reduces cost and turnaround time. The mass flow coefficient, location, width and angle were chosen as design parameters to maximize the aerodynamic performance of an aircraft. As the main contribution of this study, a detailed parametric study and optimization process were presented. The second step is to appraise the practicability of weakening the shock wave and thereby reducing the wave drag in transonic flight regime using flow control devices such as two dimensional contour bump, individual jet actuator, and also the hybrid control which includes both control devices together, thereby gaining the desired improvements in aerodynamic performance of the air-vehicle. After this study, to improve the aerodynamic performance, the flow control and shape parameters are optimized separately, combined, and in a serial combination. The remarkable part of all these

  18. Multimedia computer support for a course in ground control

    SciTech Connect

    Summers, D.A.; Unal, A.

    1996-12-31

    A prototype multimedia compact disc (CD) was created using the facilities at the Rock Mechanics and Explosives Research Center (RMERC) of the University of Missouri-Rolla (UMR) to teach a portion of a course in Ground Control. Multimedia computers offer an environment where audio-visual presentations can be made in an interactive fashion. Together with relevant animation clips, video clips, and 3-D representations, the difficulties in describing mining processes and earth structures can be overcome. This paper describes the experience gained in preparing interactive multimedia lectures on computers. The hardware and software used in creating the sound commentary, 3-D graphics, animation clips, video clips, and movies are listed. The structure of the program and how interactivity was achieved is explained in detail. Such an instructional tool is not only an excellent supplement to regular courses but it also is an inexpensive and effective way of providing distance education for mining engineers working at remote locations scattered all over the country.

  19. Intelligent Command and Control Systems for Satellite Ground Operations

    NASA Technical Reports Server (NTRS)

    Mitchell, Christine M.

    1999-01-01

    This grant, Intelligent Command and Control Systems for Satellite Ground Operations, funded by NASA Goddard Space Flight Center, has spanned almost a decade. During this time, it has supported a broad range of research addressing the changing needs of NASA operations. It is important to note that many of NASA's evolving needs, for example, use of automation to drastically reduce (e.g., 70%) operations costs, are similar requirements in both government and private sectors. Initially the research addressed the appropriate use of emerging and inexpensive computational technologies, such as X Windows, graphics, and color, together with COTS (commercial-off-the-shelf) hardware and software such as standard Unix workstations to re-engineer satellite operations centers. The first phase of research supported by this grant explored the development of principled design methodologies to make effective use of emerging and inexpensive technologies. The ultimate performance measures for new designs were whether or not they increased system effectiveness while decreasing costs. GT-MOCA (The Georgia Tech Mission Operations Cooperative Associate) and GT-VITA (Georgia Tech Visual and Inspectable Tutor and Assistant), whose latter stages were supported by this research, explored model-based design of collaborative operations teams and the design of intelligent tutoring systems, respectively. Implemented in proof-of-concept form for satellite operations, empirical evaluations of both, using satellite operators for the former and personnel involved in satellite control operations for the latter, demonstrated unequivocally the feasibility and effectiveness of the proposed modeling and design strategy underlying both research efforts. The proof-of-concept implementation of GT-MOCA showed that the methodology could specify software requirements that enabled a human-computer operations team to perform without any significant performance differences from the standard two-person satellite

  20. Ground control system for the midcourse space experiment UTC clock

    NASA Technical Reports Server (NTRS)

    Dragonette, Richard

    1994-01-01

    One goal of the Midcourse Space Experiment (MSX) spacecraft Operations Planning Center is to maintain the onboard satellite UTC clock (UTC(MSX)) to within 1 millisecond of UTC(APL) (the program requirement is 10 msec). The UTC(MSX) clock employs as its time base an APL built 5 MHz quartz oscillator, which is expected to have frequency instabilities (aging rate + drift rate + frequency offset) that will cause the clock to drift approximately two to ten milliseconds per day. The UTC(MSX) clock can be advanced or retarded by the APL MSX satellite ground control center by integer multiples of 1 millisecond. The MSX Operations Planning Center is developing software which records the drift of UTC(MSX) relative to UTC(APL) and which schedules the time of day and magnitude of UTC(MSX) clock updates up to 48 hours in advance. Because of the manner in which MSX spacecraft activities are scheduled, MSX clock updates are planned 24 to 48 hours in advance, and stored in the satellite's computer controller for later execution. Data will be collected on the drift of UTC(MSX) relative to UTC(APL) over a three to five day period. Approximately six times per day, the time offset between UTC(MSX) and UTC(APL) will be measured by APL with a resolution of less than 100 microseconds. From this data a second order analytical model of the clock's drift will be derived. This model will be used to extrapolate the offset of the MSX clock in time from the present to 48 hours in the future. MSX clock updates will be placed on the spacecraft's daily schedule whenever the predicted clock offset exceeds 0.5 milliseconds. The paper includes a discussion of how the empirical model of the MSX clock is derived from satellite telemetry data, as well as the algorithm used to schedule MSX clock updates based on the model.

  1. Proceedings, 24th international conference on ground control in mining

    SciTech Connect

    Peng, S.S.; Mark, C.; Finfinger, G.; Tadolini, S.; Wahab Khair, A.; Heasley, K.

    2005-07-01

    Topics covered: longwall mining; multiple seam mining; pillar/pillar extraction; surface subsidence; roof falls; geology; high horizontal stresses; highwall mining/slope stability; mine/roof support design; roof bolting; and detection of ground conditions.

  2. Piloted simulation of a ground-based time-control concept for air traffic control

    NASA Technical Reports Server (NTRS)

    Davis, Thomas J.; Green, Steven M.

    1989-01-01

    A joint simulation was carried out using a piloted simulator and an advanced-concept air traffic control simulation to study the acceptability and accuracy of the ground-based four-dimensional descent advisor (DA), an automation aid based on accurate models of aircraft performance and weather conditions. In the piloted simulation, airline crews executed controller-issued descent advisories along standard curved-path arrival routes and were able to achieve an arrival-time precision of plus or minus 20 s at the metering fix. An analysis of errors generated in turns resulted in a further enhancement of the DA algorithm.

  3. Grounding, bonding and shielding for safety and signal interference control

    NASA Astrophysics Data System (ADS)

    Forsyth, T. J.; Bautista, Al

    Aircraft models and other aerodynamic tests are conducted at the NASA Ames Research Center National Full Scale Aerodynamics Complex (NFAC). The models, tested in NFAC's wind tunnels, are sometimes heavily instrumented and are connected to a data acquisition system. Besides recording data for evaluation, certain critical information must be monitored to be sure the model is within operational limits. The signals for these parameters are for the most part low-level signals that require good instrumentation amplification. These amplifiers need to be grounded and shielded for common mode rejection and noise reduction. The instrumentation also needs to be grounded to prevent electrical shock hazards. The purpose of this paper is to present an understanding of the principles and purpose of grounding, bonding, and shielding.

  4. Regional ground deformation and its controlling measures in China

    NASA Astrophysics Data System (ADS)

    Zhou, Zhifang; Zhu, Haisheng; Huang, Yong

    2006-12-01

    With the development of construction of China Cities, there exist a lot of environmental geological problems involved in the geofracture, land subsidence, collapse, landslide, devolution, mudrock flow, floating sand, piping and soft ground deformation. Of big cities whose population is over one million in China, about 30 cities appears the land subsidence region. Other cities locate in the regions of collapse yellow earth or expand soil of strong swell-shrink charasteristic, soft ground and karst. In the paper, the cause and hazard of regionality ground deformation is summed up. The causes of regional land deformation caused by the natural geological effect and activities of human being are analyzed. According to the length of deformation course and endanger of society, economy and life, land deformation involves three types, that is, the delay, rapid and break land deformation. And the concrete countermeasure and method are provided.

  5. Ground-borne vibrations caused by trams, and control measures

    NASA Astrophysics Data System (ADS)

    Lang, J.

    1988-01-01

    Ground-borne vibrations caused by trams in streets within cities are a special problem. The vibrations propagating to the buildings close to the track and within these buildings may be felt by the inhabitants and may be heard via the structure-borne sound radiated to the rooms. In quiet sites during night-time the relevant limits are often exceeded, if the tracks are laid in the normal manner. Experiments with tracks on floating concrete slabs on mineral wool and with "barriers" in the ground alongside the track show that the vibrations reaching buildings near the track may be reduced considerably.

  6. Definition of ground test for Large Space Structure (LSS) control verification

    NASA Technical Reports Server (NTRS)

    Waites, H. B.; Doane, G. B., III; Tollison, D. K.

    1984-01-01

    An overview for the definition of a ground test for the verification of Large Space Structure (LSS) control is given. The definition contains information on the description of the LSS ground verification experiment, the project management scheme, the design, development, fabrication and checkout of the subsystems, the systems engineering and integration, the hardware subsystems, the software, and a summary which includes future LSS ground test plans. Upon completion of these items, NASA/Marshall Space Flight Center will have an LSS ground test facility which will provide sufficient data on dynamics and control verification of LSS so that LSS flight system operations can be reasonably ensured.

  7. A ground test program to support condition monitoring of a spacecraft attitude control propulsion system

    NASA Technical Reports Server (NTRS)

    Clark, Douglas J.; Lester, Robert W.; Baroth, Edmund C.; Coleman, Arthur L.

    1991-01-01

    The Comet Rendezvous Asteroid Flyby (CRAF) mission involves seven years of flight from 0.6 to 4.57 Astronomical Units (AU), followed by about 915 days of maneuvering around a comet. Ground testing will characterize the very critical attitude control system thrusters' fuel consumption and performance for all anticipated fuel temperatures over thruster life. The ground test program characterization will support flight condition monitoring. A commercial software application hosted on a commercial microcomputer will control ground test operations and data acquisition using a newly designed thrust stand. The data acquisition and control system uses a graphics-based language and features a visual interface to integrate data acquisition and control.

  8. Control performance evaluation of railway vehicle MR suspension using fuzzy sky-ground hook control algorithm

    NASA Astrophysics Data System (ADS)

    Ha, S. H.; Choi, S. B.; Lee, G. S.; Yoo, W. H.

    2013-02-01

    This paper presents control performance evaluation of railway vehicle featured by semi-active suspension system using magnetorheological (MR) fluid damper. In order to achieve this goal, a nine degree of freedom of railway vehicle model, which includes car body and bogie, is established. The wheel-set data is loaded from measured value of railway vehicle. The MR damper system is incorporated with the governing equation of motion of the railway vehicle model which includes secondary suspension. To illustrate the effectiveness of the controlled MR dampers on suspension system of railway vehicle, the control law using the sky-ground hook controller is adopted. This controller takes into account for both vibration control of car body and increasing stability of bogie by adopting a weighting parameter between two performance requirements. The parameters appropriately determined by employing a fuzzy algorithm associated with two fuzzy variables: the lateral speed of the car body and the lateral performance of the bogie. Computer simulation results of control performances such as vibration control and stability analysis are presented in time and frequency domains.

  9. System and method for transferring telemetry data between a ground station and a control center

    NASA Technical Reports Server (NTRS)

    Ray, Timothy J. (Inventor); Ly, Vuong T. (Inventor)

    2012-01-01

    Disclosed herein are systems, computer-implemented methods, and tangible computer-readable media for coordinating communications between a ground station, a control center, and a spacecraft. The method receives a call to a simple, unified application programmer interface implementing communications protocols related to outer space, when instruction relates to receiving a command at the control center for the ground station generate an abstract message by agreeing upon a format for each type of abstract message with the ground station and using a set of message definitions to configure the command in the agreed upon format, encode the abstract message to generate an encoded message, and transfer the encoded message to the ground station, and perform similar actions when the instruction relates to receiving a second command as a second encoded message at the ground station from the control center and when the determined instruction type relates to transmitting information to the control center.

  10. A controlled experiment in ground water flow model calibration

    USGS Publications Warehouse

    Hill, M.C.; Cooley, R.L.; Pollock, D.W.

    1998-01-01

    Nonlinear regression was introduced to ground water modeling in the 1970s, but has been used very little to calibrate numerical models of complicated ground water systems. Apparently, nonlinear regression is thought by many to be incapable of addressing such complex problems. With what we believe to be the most complicated synthetic test case used for such a study, this work investigates using nonlinear regression in ground water model calibration. Results of the study fall into two categories. First, the study demonstrates how systematic use of a well designed nonlinear regression method can indicate the importance of different types of data and can lead to successive improvement of models and their parameterizations. Our method differs from previous methods presented in the ground water literature in that (1) weighting is more closely related to expected data errors than is usually the case; (2) defined diagnostic statistics allow for more effective evaluation of the available data, the model, and their interaction; and (3) prior information is used more cautiously. Second, our results challenge some commonly held beliefs about model calibration. For the test case considered, we show that (1) field measured values of hydraulic conductivity are not as directly applicable to models as their use in some geostatistical methods imply; (2) a unique model does not necessarily need to be identified to obtain accurate predictions; and (3) in the absence of obvious model bias, model error was normally distributed. The complexity of the test case involved implies that the methods used and conclusions drawn are likely to be powerful in practice.Nonlinear regression was introduced to ground water modeling in the 1970s, but has been used very little to calibrate numerical models of complicated ground water systems. Apparently, nonlinear regression is thought by many to be incapable of addressing such complex problems. With what we believe to be the most complicated synthetic

  11. Eurobot Ground Prototype Control System Overview & Tests Results

    NASA Astrophysics Data System (ADS)

    Merlo, Andrea; Martelli, Andrea; Pensavalle, Emanuele; Ferraris, Simona; Didot, Frederic

    2010-08-01

    In the planned missions on Moon and Mars, robotics can play a key role, as robots can both assist astronauts and, above all, relieve them of dangerous or too difficult tasks. To this aim, both cooperative capabilities and a great level of autonomy are needed: the robotic crew assistant must be able to work on its own, without supervision by humans, and to help astronauts to accomplish tasks otherwise unfeasible for them. Within this context, a project named Eurobot Ground Prototype, conducted in conjunction with ESA and Thales Alenia Space, is presented. EGP is a dual-arm mobile manipulator and exploits both stereo cameras and force/torque sensors in order to rely on visual and force feedback. This paper provides an overview of the performed and on going activities within the Eurobot Ground Prototype project.

  12. Antenna testing for the Inmarsat 2 ground control system

    NASA Astrophysics Data System (ADS)

    Ashton, C.

    1992-02-01

    This article describes how the antennas of the Inmarsat 2 TT&C and IOT ground stations were tested and calibrated. It explains the main test methods used, giving the theory behind the tests and indicates some of the practical difficulties encountered during testing. Techniques described include the use of radio stars, boresight antennas and satellite verification testing using Intelsat and Inmarsat satellites. Parameters tested include gain, G/T (figure of merit), sidelobe patterns, cross polar discrimination and isolation.

  13. Load control system. [for space shuttle external tank ground tests

    NASA Technical Reports Server (NTRS)

    Grosse, J. C.

    1977-01-01

    The load control system developed for the shuttle external structural tests is described. The system consists of a load programming/display module, and a load control module along with the following hydraulic system components: servo valves, dump valves, hydraulic system components, and servo valve manifold blocks. One load programming/display subsystem can support multiple load control subsystem modules.

  14. JF-104 ground testing reaction control system (RCS) jets

    NASA Technical Reports Server (NTRS)

    1961-01-01

    JF-104A (formerly YF-104A, serial # 55-2961) was modifed with a hydrogen peroxide reaction control system (RCS). Following a zoom climb to altitudes in the vicinity of 80,000 feet, the RCS system gave the aircraft controllability in the thin upper atmosphere where conventional control surfaces are ineffective.

  15. Temperature and Humidity Independent Control Research on Ground Source Heat Pump Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Chen, G.; Wang, L. L.

    Taking green demonstration center building air conditioning system as an example, this paper presents the temperature and humidity independent control system combined with ground source heat pump system, emphasis on the design of dry terminal device system, fresh air system and ground source heat pump system.

  16. Remote and Local Display Applications for the Launch Control System and the Kennedy Ground Control System

    NASA Technical Reports Server (NTRS)

    Gordillo, Orlando Enrique

    2016-01-01

    This spring 2016 semester, I interned through the OSSI Intern program, sponsored by USRA, at NASA's Kennedy Space Center. I worked under the Engineering Directorate (NE-ES), under the software branch. We are creating the future Launch Control System (LCS). The system monitors, manages and sends commands to ground or flight subsystems. I worked on both the remote applications, which reside in the firing room, and local applications that are in Panel Views. The two kinds of applications have completely different development environments but work in parallel. For each project I was assigned to work with a specific subsystems team. I worked with the Launch Release Subsystem (LRS) on the remote side and with the Environmental Control Subsystem (ECS) on the Local side.

  17. Commercial off the Shelf Ground Control Supports Calibration and Conflation from Ground to Space Based Sensors

    NASA Astrophysics Data System (ADS)

    Danielová, M.; Hummel, P.

    2016-06-01

    The need for rapid deployment of aerial and satellite imagery in support of GIS and engineering integration projects require new sources of geodetic control to ensure the accuracy for geospatial projects. In the past, teams of surveyors would need to deploy to project areas to provide targeted or photo identifiable points that are used to provide data for orthorecificaion, QA/QC and calibration for multi-platform sensors. The challenge of integrating street view, UAS, airborne and Space based sensors to produce the common operational picture requires control to tie multiple sources together. Today commercial off the shelf delivery of existing photo identifiable control is increasing the speed of deployment of this data without having to revisit sites over and over again. The presentation will discuss the processes developed by CompassData to build a global library of 40,000 control points available today. International Organization for Standardization (ISO) based processes and initiatives ensure consistent quality of survey data, photo identifiable features selected and meta data to support photogrammetrist, engineers and GIS professionals to quickly deliver projects with better accuracy.

  18. Piloted simulation of a ground-based time-control concept for air traffic control

    NASA Technical Reports Server (NTRS)

    Davis, Thomas J.; Green, Steven M.

    1989-01-01

    A concept for aiding air traffic controllers in efficiently spacing traffic and meeting scheduled arrival times at a metering fix was developed and tested in a real time simulation. The automation aid, referred to as the ground based 4-D descent advisor (DA), is based on accurate models of aircraft performance and weather conditions. The DA generates suggested clearances, including both top-of-descent-point and speed-profile data, for one or more aircraft in order to achieve specific time or distance separation objectives. The DA algorithm is used by the air traffic controller to resolve conflicts and issue advisories to arrival aircraft. A joint simulation was conducted using a piloted simulator and an advanced concept air traffic control simulation to study the acceptability and accuracy of the DA automation aid from both the pilot's and the air traffic controller's perspectives. The results of the piloted simulation are examined. In the piloted simulation, airline crews executed controller issued descent advisories along standard curved path arrival routes, and were able to achieve an arrival time precision of + or - 20 sec at the metering fix. An analysis of errors generated in turns resulted in further enhancements of the algorithm to improve the predictive accuracy. Evaluations by pilots indicate general support for the concept and provide specific recommendations for improvement.

  19. Method of Controlling Steering of a Ground Vehicle

    NASA Technical Reports Server (NTRS)

    Dawson, Andrew D. (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Guo, Raymond (Inventor); Atluri, Venkata Prasad (Inventor)

    2016-01-01

    A method of controlling steering of a vehicle through setting wheel angles of a plurality of modular electronic corner assemblies (eModules) is provided. The method includes receiving a driving mode selected from a mode selection menu. A position of a steering input device is determined in a master controller. A velocity of the vehicle is determined, in the master controller, when the determined position of the steering input device is near center. A drive mode request corresponding to the selected driving mode to the plurality of steering controllers is transmitted to the master controller. A required steering angle of each of the plurality of eModules is determined, in the master controller, as a function of the determined position of the steering input device, the determined velocity of the vehicle, and the selected first driving mode. The eModules are set to the respective determined steering angles.

  20. Ground Control for Non-Emplacement Drifts for LA

    SciTech Connect

    D. Tang

    2004-02-26

    The purpose of this calculation is to analyze the stability of repository non-emplacement drifts during the preclosure period, and to provide a final ground support method for non-emplacement drifts for the License Application (LA). This calculation will provide input for the development of LA documents. The scope of this calculation is limited to the non-emplacement drifts including access mains, ramps, exhaust mains, turnouts, intersections between access mains and turnouts, and intersections between exhaust mains and emplacement drifts, portals, TBM launch chambers, observation drift and test alcove in the performance confirmation (PC) facilities, etc. The calculation is limited to the non-emplacement drifts subjected to a combined loading of in-situ stress, seismic stress, and/or thermal stress. Other effects such as hydrological and chemical effects are not considered in this analysis.

  1. Onboard utilization of ground control points for image correction. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Operation of a navigation system, centered around image correction, was simulated and the system performance was analyzed. Onboard utilization of ground control points for image correction is summarized. Simulation results, and recommendations for future mission requirements are presented.

  2. Use of synthetic ground covers to control weeds in blackberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control in blackberries (Rubus spp.) is a serious problem for organic producers and those who wish to reduce their reliance on herbicides. Three landscape fabrics (Dewitt, Texel, and a white polyester weave) and one industrial grade white on black plastic were used for weed control in conjucti...

  3. Ground facility for large space structures dynamics and control verification

    NASA Technical Reports Server (NTRS)

    Waites, Henry

    1986-01-01

    NASA Marshall Space Flight Center has developed a facility in which closed loop control of Large Space Structures (LSS) can be demonstrated and verified. The main objective of the facility is to verify LSS control system techniques so that on-orbit performance can be unsured. The facility consists of an LSS test article or payload which is connected to a 3-axis angular pointing mount assembly that provides control torque commands. The angular pointing mount assembly is attached to a base excitation system which will simulate disturbances most likely to occur for Orbiter and DOD payloads. The control computer contains the calibration software, the reference systems, the alignment procedures, the telemetry software, and the control algorithms. The total system is suspended in such a fashion that the LSS test article has the characteristics common to all LSS.

  4. Definition of ground test for Large Space Structure (LSS) control verification, appendix G

    NASA Technical Reports Server (NTRS)

    1984-01-01

    A Large Space Structure (LSS) ground test facility was developed to help verify LSS passive and active control theories. The facility also perform: (1) subsystem and component testing; (2) remote sensing and control; (3) parameter estimation and model verification; and (4) evolutionary modeling and control. The program is examined as is and looks at the first experiment to be performed in the laboratory.

  5. Advanced Ground Systems Maintenance Cryogenics Test Lab Control System Upgrade Project

    NASA Technical Reports Server (NTRS)

    Harp, Janice Leshay

    2014-01-01

    This project will outfit the Simulated Propellant Loading System (SPLS) at KSC's Cryogenics Test Laboratory with a new programmable logic control system. The control system upgrade enables the Advanced Ground Systems Maintenace Element Integration Team and other users of the SPLS to conduct testing in a controls environment similar to that used at the launch pad.

  6. Ground-water contamination control: Detection and remedial planning

    SciTech Connect

    Woldt, W.E.

    1990-01-01

    The dissertation is divided into three main sections that correspond to a typical sequence of actions resulting in a final remedial action plan for handling contamination at a particular site. The first section develops a methodology for detecting and mapping suspected contamination using multiple sources of data. Different data types are combined by using a modified form of kriging with uncertain data, termed compound kriging. In addition, the use of fuzzy set theory merged with geostatistics is explored as a possible mapping technique when variogram parameters are difficult to quantify. A decision support system for observation network design is presented in the second section. Network design is approached from a multiple objective decision making perspective. The objective is to identify the most cost-effective network design while considering the trade-off between performance and cost. Geostatistical variance reduction analysis and prior knowledge related to the site are used as performance measures in the decision support system. A remedial action design support system is described in the third section. Three dimensional geostatistical simulation and analytical ground water modeling are used to assess the need for further remedial action planning. In addition, a methodology for measuring the performance of candidate remediation systems under conditions of uncertainty in aquifer parameters and plume location is presented. These performance measures, combined with cost factors, are used in a multiple-criteria decision making system to determine the preferred clean up system for a site being investigated.

  7. Preliminary Design of Monitoring and Control Subsystem for GNSS Ground Station

    NASA Astrophysics Data System (ADS)

    Jeong, Seongkyun; Lee, Jae-Eun; Park, Hanearl; Lee, Sanguk; Kim, Jaehoon

    2008-06-01

    GNSS (Global Navigation Satellite System) Ground Station monitors navigation satellite signal, analyzes navigation result, and uploads correction information to satellite. GNSS Ground Station is considered as a main object for constructing GNSS infra-structure and applied in various fields. ETRI (Electronics and Telecommunications Research Institute) is developing Monitoring and Control subsystem, which is subsystem of GNSS Ground Station. Monitoring and Control subsystem acquires GPS and Galileo satellite signal and provides signal monitoring data to GNSS control center. In this paper, the configurations of GNSS Ground Station and Monitoring and Control subsystem are introduced and the preliminary design of Monitoring and Control subsystem is performed. Monitoring and Control subsystem consists of data acquisition module, data formatting and archiving module, data error correction module, navigation solution determination module, independent quality monitoring module, and system operation and maintenance module. The design process uses UML (Unified Modeling Language) method which is a standard for developing software and consists of use-case modeling, domain design, software structure design, and user interface structure design. The preliminary design of Monitoring and Control subsystem enhances operation capability of GNSS Ground Station and is used as basic material for detail design of Monitoring and Control subsystem.

  8. Tug fleet and ground operations schedules and controls. Volume 2: part 1

    NASA Technical Reports Server (NTRS)

    1975-01-01

    This Tug Fleet and Ground Operations Schedules and Controls Study addresses both ground operational data and technical requirements that span the Tug planning phase and operations phase. A similar study covering mission operations (by others) provides the complimentary flight operations details. The two studies provide the planning data requirements, resource allocation, and control milestones for supporting the requirements of the STS program. This Tug Fleet and Ground Operations Schedules and Controls Study incorporates the basic ground operations requirements and concepts provided by previous studies with the interrelationships of the planning, IUS transition, and Tug fleet operations phases. The interrelationships of these phases were studied as a system to optimize overall program benefits and minimize operational risk factors.

  9. Intelligent command and control systems for satellite ground operations

    NASA Technical Reports Server (NTRS)

    Mitchell, Christine M.

    1994-01-01

    The Georgia Tech portion of the Intelligent Control Center project includes several complementary activities. Two major activities entail thesis level research; the other activities are either support activities or preliminary explorations (e.g., task analyses) to support the research. The first research activity is the development of principles for the design of active interfaces to support monitoring during real-time supports. It is well known that as the operator's task becomes less active, i.e., more monitoring and less active control, there is concern that the operator will be less involved and less able to rapidly identify anomalous or failure situations. The research project to design active monitoring interfaces is an attempt to remediate this undesirable side-effect of increasingly automated control systems that still depend ultimately on operator supervision. The second research activity is the exploration of the use of case-based reasoning as a way to accumulate operator experience and make it available in computational form.

  10. Ground Control Setup of the (LIF) Large Isothermal Furnace

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Large Isothermal Furnace (LIF) was flown on a mission in cooperation with the National Space Development Agency (NASDA) of Japan. LIF is a vacuum-heating furnace designed to heat large samples uniformly. The furnace consists of a sample container and heating element surrounded by a vacuum chamber. A crewmemeber will insert a sample cartridge into the furnace. The furnace will be activated and operations will be controlled automatically by a computer in response to an experiment number entered on the control panel. At the end of operations, helium will be discharged into the furnace, allowing cooling to start. Cooling will occur through the use of a water jacket while rapid cooling of samples can be accomplished through a controlled flow of helium. Data from experiments will help scientists better understand this important process which is vital to the production of high-quality semiconductor crystals.

  11. Ground control requirements for precision processing of ERTS images

    USGS Publications Warehouse

    Burger, Thomas C.

    1972-01-01

    When the first Earth Resources Technology Satellite (ERTS-A) flies in 1972, NASA expects to receive and bulk-process 9,000 images a week. From this deluge of images, a few will be selected for precision processing; that is, about 5 percent will be further treated to improve the geometry of the scene, both in the relative and absolute sense. Control points are required for this processing. This paper describes the control requirements for relating ERTS images to a reference surface of the earth. Enough background on the ERTS-A satellite is included to make the requirements meaningful to the user.

  12. Weed control in blackberries using synthetic ground covers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control in blackberries (Rubus spp.) is a serious problem for organic producers and those who wish to reduce their reliance on herbicides. Three landscape fabrics (Dewitt, Texel, and a white polyester weave) and one industrial grade white on black plastic were used in conjuction with newly pla...

  13. Ground control requirements for precision processing of ERTS images

    USGS Publications Warehouse

    Burger, Thomas C.

    1973-01-01

    With the successful flight of the ERTS-1 satellite, orbital height images are available for precision processing into products such as 1:1,000,000-scale photomaps and enlargements up to 1:250,000 scale. In order to maintain positional error below 100 meters, control points for the precision processing must be carefully selected, clearly definitive on photos in both X and Y. Coordinates of selected control points measured on existing ½ and 15-minute standard maps provide sufficient accuracy for any space imaging system thus far defined. This procedure references the points to accepted horizontal and vertical datums. Maps as small as 1:250,000 scale can be used as source material for coordinates, but to maintain the desired accuracy, maps of 1:100,000 and larger scale should be used when available.

  14. 9th international conference on ground control in mining

    SciTech Connect

    Peng, S.S.

    1990-01-01

    This conference provides papers related to strata control in underground mining environments. The bulk of these text are directly applicable to coal mining although some are applied to hard rock minerals. Performance testing of roof bolts, trusses, and other support devices are discussed. Information on computer software for stress and stability analyses are also provided. Case studies and discussions on mine roadway safety is provided.

  15. 1997 annual ground control operating plan for the Waste Isolation Pilot Plant

    SciTech Connect

    1997-02-01

    This plan presents background information and a working guide to assist Mine Operations and Engineering in developing strategies for addressing ground control issues at the Waste Isolation Pilot Plant (WIPP). With the anticipated receipt of waste in late 1997, this document provides additional detail to Panel 1 activities and options. The plan also serves as a foundation document for development and revision of the annual long-term ground control plan. Section 2.0 documents the current status of all underground excavations with respect to location, geology, geometry, age, ground support, operational use, projected life, and physical conditions. Section 3.0 presents the methods used to evaluate ground conditions, including visual observations of the roof, ribs, and floor, inspection of observation holes, and review of instrumentation data. Section 4.0 lists several ground support options and specific applications of each. Section 5.0 discusses remedial ground control measures that have been implemented to date. Section 6.0 presents projections and recommendations for ground control actions based on the information in Sections 2.0 through 5.0 of this plan and on a rating of the critical nature of each specific area. Section 7.0 presents a summary statement, and Section 8.0 includes references. Appendix A provides an overview and critique of ground control systems that have been, or may be, used at the site. Because of the dynamic nature of the underground openings and associated geotechnical activities, this plan will be revised as additional data are incorporated.

  16. Pushing the Limits of Cubesat Attitude Control: A Ground Demonstration

    NASA Technical Reports Server (NTRS)

    Sanders, Devon S.; Heater, Daniel L.; Peeples, Steven R.; Sules. James K.; Huang, Po-Hao Adam

    2013-01-01

    A cubesat attitude control system (ACS) was designed at the NASA Marshall Space Flight Center (MSFC) to provide sub-degree pointing capabilities using low cost, COTS attitude sensors, COTS miniature reaction wheels, and a developmental micro-propulsion system. The ACS sensors and actuators were integrated onto a 3D-printed plastic 3U cubesat breadboard (10 cm x 10 cm x 30 cm) with a custom designed instrument board and typical cubesat COTS hardware for the electrical, power, and data handling and processing systems. In addition to the cubesat development, a low-cost air bearing was designed and 3D printed in order to float the cubesat in the test environment. Systems integration and verification were performed at the MSFC Small Projects Rapid Integration & Test Environment laboratory. Using a combination of both the miniature reaction wheels and the micro-propulsion system, the open and closed loop control capabilities of the ACS were tested in the Flight Robotics Laboratory. The testing demonstrated the desired sub-degree pointing capability of the ACS and also revealed the challenges of creating a relevant environment for development testin

  17. Definition of ground test for verification of large space structure control

    NASA Technical Reports Server (NTRS)

    Doane, G. B., III; Glaese, J. R.; Tollison, D. K.; Howsman, T. G.; Curtis, S. (Editor); Banks, B.

    1984-01-01

    Control theory and design, dynamic system modelling, and simulation of test scenarios are the main ideas discussed. The overall effort is the achievement at Marshall Space Flight Center of a successful ground test experiment of a large space structure. A simplified planar model of ground test experiment of a large space structure. A simplified planar model of ground test verification was developed. The elimination from that model of the uncontrollable rigid body modes was also examined. Also studied was the hardware/software of computation speed.

  18. Factors controlling the regional distribution of vanadium in ground water

    USGS Publications Warehouse

    Wright, Michael T.; Belitz, Kenneth

    2010-01-01

    Although the ingestion of vanadium (V) in drinking water may have possible adverse health effects, there have been relatively few studies of V in groundwater. Given the importance of groundwater as a source of drinking water in many areas of the world, this study examines the potential sources and geochemical processes that control the distribution of V in groundwater on a regional scale. Potential sources of V to groundwater include dissolution of V rich rocks, and waste streams from industrial processes. Geochemical processes such as adsorption/desorption, precipitation/dissolution, and chemical transformations control V concentrations in groundwater. Based on thermodynamic data and laboratory studies, V concentrations are expected to be highest in samples collected from oxic and alkaline groundwater. However, the extent to which thermodynamic data and laboratory results apply to the actual distribution of V in groundwater is not well understood. More than 8400 groundwater samples collected in California were used in this study. Of these samples, high (> or = 50 μg/L) and moderate (25 to 49 μg/L) V concentrations were most frequently detected in regions where both source rock and favorable geochemical conditions occurred. The distribution of V concentrations in groundwater samples suggests that significant sources of V are mafic and andesitic rock. Anthropogenic activities do not appear to be a significant contributor of V to groundwater in this study. High V concentrations in groundwater samples analyzed in this study were almost always associated with oxic and alkaline groundwater conditions, which is consistent with predictions based on thermodynamic data.

  19. Open solutions to distributed control in ground tracking stations

    NASA Technical Reports Server (NTRS)

    Heuser, William Randy

    1994-01-01

    The advent of high speed local area networks has made it possible to interconnect small, powerful computers to function together as a single large computer. Today, distributed computer systems are the new paradigm for large scale computing systems. However, the communications provided by the local area network is only one part of the solution. The services and protocols used by the application programs to communicate across the network are as indispensable as the local area network. And the selection of services and protocols that do not match the system requirements will limit the capabilities, performance, and expansion of the system. Proprietary solutions are available but are usually limited to a select set of equipment. However, there are two solutions based on 'open' standards. The question that must be answered is 'which one is the best one for my job?' This paper examines a model for tracking stations and their requirements for interprocessor communications in the next century. The model and requirements are matched with the model and services provided by the five different software architectures and supporting protocol solutions. Several key services are examined in detail to determine which services and protocols most closely match the requirements for the tracking station environment. The study reveals that the protocols are tailored to the problem domains for which they were originally designed. Further, the study reveals that the process control model is the closest match to the tracking station model.

  20. Feed forward and feedback control for over-ground locomotion in anaesthetized cats.

    PubMed

    Mazurek, K A; Holinski, B J; Everaert, D G; Stein, R B; Etienne-Cummings, R; Mushahwar, V K

    2012-04-01

    The biological central pattern generator (CPG) integrates open and closed loop control to produce over-ground walking. The goal of this study was to develop a physiologically based algorithm capable of mimicking the biological system to control multiple joints in the lower extremities for producing over-ground walking. The algorithm used state-based models of the step cycle each of which produced different stimulation patterns. Two configurations were implemented to restore over-ground walking in five adult anaesthetized cats using intramuscular stimulation (IMS) of the main hip, knee and ankle flexor and extensor muscles in the hind limbs. An open loop controller relied only on intrinsic timing while a hybrid-CPG controller added sensory feedback from force plates (representing limb loading), and accelerometers and gyroscopes (representing limb position). Stimulation applied to hind limb muscles caused extension or flexion in the hips, knees and ankles. A total of 113 walking trials were obtained across all experiments. Of these, 74 were successful in which the cats traversed 75% of the 3.5 m over-ground walkway. In these trials, the average peak step length decreased from 24.9 ± 8.4 to 21.8 ± 7.5 (normalized units) and the median number of steps per trial increased from 7 (Q1 = 6, Q3 = 9) to 9 (8, 11) with the hybrid-CPG controller. Moreover, within these trials, the hybrid-CPG controller produced more successful steps (step length ≤ 20 cm; ground reaction force ≥ 12.5% body weight) than the open loop controller: 372 of 544 steps (68%) versus 65 of 134 steps (49%), respectively. This supports our previous preliminary findings, and affirms that physiologically based hybrid-CPG approaches produce more successful stepping than open loop controllers. The algorithm provides the foundation for a neural prosthetic controller and a framework to implement more detailed control of locomotion in the future. PMID:22328615

  1. Feed forward and feedback control for over-ground locomotion in anaesthetized cats

    NASA Astrophysics Data System (ADS)

    Mazurek, K. A.; Holinski, B. J.; Everaert, D. G.; Stein, R. B.; Etienne-Cummings, R.; Mushahwar, V. K.

    2012-04-01

    The biological central pattern generator (CPG) integrates open and closed loop control to produce over-ground walking. The goal of this study was to develop a physiologically based algorithm capable of mimicking the biological system to control multiple joints in the lower extremities for producing over-ground walking. The algorithm used state-based models of the step cycle each of which produced different stimulation patterns. Two configurations were implemented to restore over-ground walking in five adult anaesthetized cats using intramuscular stimulation (IMS) of the main hip, knee and ankle flexor and extensor muscles in the hind limbs. An open loop controller relied only on intrinsic timing while a hybrid-CPG controller added sensory feedback from force plates (representing limb loading), and accelerometers and gyroscopes (representing limb position). Stimulation applied to hind limb muscles caused extension or flexion in the hips, knees and ankles. A total of 113 walking trials were obtained across all experiments. Of these, 74 were successful in which the cats traversed 75% of the 3.5 m over-ground walkway. In these trials, the average peak step length decreased from 24.9 ± 8.4 to 21.8 ± 7.5 (normalized units) and the median number of steps per trial increased from 7 (Q1 = 6, Q3 = 9) to 9 (8, 11) with the hybrid-CPG controller. Moreover, within these trials, the hybrid-CPG controller produced more successful steps (step length ≤ 20 cm ground reaction force ≥ 12.5% body weight) than the open loop controller: 372 of 544 steps (68%) versus 65 of 134 steps (49%), respectively. This supports our previous preliminary findings, and affirms that physiologically based hybrid-CPG approaches produce more successful stepping than open loop controllers. The algorithm provides the foundation for a neural prosthetic controller and a framework to implement more detailed control of locomotion in the future.

  2. Eccentricity and argument of perigee control for orbits with repeat ground tracks

    NASA Technical Reports Server (NTRS)

    Vincent, Mark A.

    1992-01-01

    In order to gain an understanding into the problem of eccentricity (e) and argument of perigee (omega) control for TOPEX/Poseidon, the two cases where the highest latitude crossing time and one of the equator crossings are held constant are investigated. Variations in e and omega cause a significant effect on the satellite's ground-track repeatability. Maintaining e and omega near their frozen values will minimize this variation. Analytical expressions are found to express this relationship while keeping an arbitrary point of the ground track fixed. The initial offset of the ground track from its nominal path determines the subsequent evolution of e and omega about their frozen values. This long-term behavior is numerically determined using an earth gravitational field including the first 17 zonal harmonics. The numerical results are plotted together with the analytical constraints to see if the later values of e and omega cause unacceptable deviation in the ground track.

  3. Maneuver Planning for Conjunction Risk Mitigation with Ground-track Control Requirements

    NASA Technical Reports Server (NTRS)

    McKinley, David

    2008-01-01

    The planning of conjunction Risk Mitigation Maneuvers (RMM) in the presence of ground-track control requirements is analyzed. Past RMM planning efforts on the Aqua, Aura, and Terra spacecraft have demonstrated that only small maneuvers are available when ground-track control requirements are maintained. Assuming small maneuvers, analytical expressions for the effect of a given maneuver on conjunction geometry are derived. The analytical expressions are used to generate a large trade space for initial RMM design. This trade space represents a significant improvement in initial maneuver planning over existing methods that employ high fidelity maneuver models and propagation.

  4. The Next Generation of Ground Operations Command and Control; Scripting in C no. and Visual Basic

    NASA Technical Reports Server (NTRS)

    Ritter, George; Pedoto, Ramon

    2010-01-01

    Scripting languages have become a common method for implementing command and control solutions in space ground operations. The Systems Test and Operations Language (STOL), the Huntsville Operations Support Center (HOSC) Scripting Language Processor (SLP), and the Spacecraft Control Language (SCL) offer script-commands that wrap tedious operations tasks into single calls. Since script-commands are interpreted, they also offer a certain amount of hands-on control that is highly valued in space ground operations. Although compiled programs seem to be unsuited for interactive user control and are more complex to develop, Marshall Space flight Center (MSFC) has developed a product called the Enhanced and Redesign Scripting (ERS) that makes use of the graphical and logical richness of a programming language while offering the hands-on and ease of control of a scripting language. ERS is currently used by the International Space Station (ISS) Payload Operations Integration Center (POIC) Cadre team members. ERS integrates spacecraft command mnemonics, telemetry measurements, and command and telemetry control procedures into a standard programming language, while making use of Microsoft's Visual Studio for developing Visual Basic (VB) or C# ground operations procedures. ERS also allows for script-style user control during procedure execution using a robust graphical user input and output feature. The availability of VB and C# programmers, and the richness of the languages and their development environment, has allowed ERS to lower our "script" development time and maintenance costs at the Marshall POIC.

  5. Mixed Waste Management Facility (MWMF) Old Burial Ground (OBG) source control technology and inventory study

    SciTech Connect

    Flach, G.P.; Rehder, T.E.; Kanzleiter, J.P.

    1996-10-02

    This report has been developed to support information needs for wastes buried in the Burial Ground Complex. Information discussed is presented in a total of four individual attachments. The general focus of this report is to collect information on estimated source inventories, leaching studies, source control technologies, and to provide information on modeling parameters and associated data deficiencies.

  6. The Ground Control Room as an Enabling Technology in the Unmanned Aerial System

    NASA Technical Reports Server (NTRS)

    Gear, Gary; Mace, Thomas

    2007-01-01

    This viewgraph presentation reviews the development of the ground control room as an required technology for the use of an Unmanned Aerial system. The Unmanned Aerial system is a strategic component of the Global Observing System, which will serve global science needs. The unmanned aerial system will use the same airspace as manned aircraft, therefore there will be unique telemetry needs.

  7. 77 FR 26046 - Proposed Extension of Existing Information Collection; Ground Control for Surface Coal Mines and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-02

    ... for Surface Coal Mines and Surface Work Areas of Underground Coal Mines AGENCY: Mine Safety and Health... related to this safety standard on ground control plans for surface coal mines and surface work areas of... for Surface Coal Mines and Surface Work Areas of Underground Coal Mines. OMB Number:...

  8. First conference on ground control problems in the Illinois Coal Basin: proceedings

    SciTech Connect

    Chugh, Y. P.; Van Besien, A.

    1980-06-01

    The first conference on ground control problems in the Illinois Coal Basin was held at the Southern Illinois University at Carbondale, Illinois, August 22-24, 1979. Twenty-one papers from the proceedings have been entered individually into EDB; one had been entered previously from other sources. (LTN)

  9. Geometric Calibration of ZIYUAN-3 Three-Line Cameras Combining Ground Control Points and Lines

    NASA Astrophysics Data System (ADS)

    Cao, Jinshan; Yuan, Xiuxiao; Gong, Jianya

    2016-06-01

    Due to the large biases between the laboratory-calibrated values of the orientation parameters and their in-orbit true values, the initial direct georeferencing accuracy of the Ziyuan-3 (ZY-3) three-line camera (TLC) images can only reach the kilometre level. In this paper, a point-based geometric calibration model of the ZY-3 TLCs is firstly established by using the collinearity constraint, and then a line-based geometric calibration model is established by using the coplanarity constraint. With the help of both the point-based and the line-based models, a feasible in-orbit geometric calibration approach for the ZY-3 TLCs combining ground control points (GCPs) and ground control lines (GCLs) is presented. Experimental results show that like GCPs, GCLs can also provide effective ground control information for the geometric calibration of the ZY-3 TLCs. The calibration accuracy of the look angles of charge-coupled device (CCD) detectors achieved by using the presented approach reached up to about 1.0''. After the geometric calibration, the direct georeferencing accuracy of the ZY-3 TLC images without ground controls was significantly improved from the kilometre level to better than 11 m in planimetry and 9 m in height. A more satisfactory georeferencing accuracy of better than 3.5 m in planimetry and 3.0 m in height was achieved after the block adjustment with four GCPs.

  10. Proposed ground-based control of accelerometer on Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Delombard, Richard

    1993-01-01

    This paper describes the innovative control of an accelerometer to support the needs of the scientists operating science experiments that are on-board Space Station Freedom (SSF). Accelerometers in support of science experiments on the shuttle have typically been passive, record-only devices that present data only after the mission or that present limited data to the crew or ground operators during the mission. With the advent of science experiment operations on SSF, the principal investigators will need microgravity acceleration data during, as well as after, experiment operations. Because their data requirements may change during the experiment operations, the principal investigators will be allocated some control of accelerometer parameters. This paper summarizes the general-purpose Space Acceleration Measurement System (SAMS) operation that supports experiments on the shuttle and describes the control of the SAMS for Space Station Freedom. Emphasis is placed on the proposed ground-based control of the accelerometer by the principal investigators.

  11. Apollo experience report: Flight-control data needs, terminal display devices, and ground system configuration requirements

    NASA Technical Reports Server (NTRS)

    Hoover, R. A.

    1974-01-01

    The development of flight-control facilities for the Apollo program is reviewed from the viewpoint of the user organization. These facilities are treated in three categories: data systems, ground-based display and control systems, and configuration management. The effects of certain Apollo program factors on the selection, sizing, and configuration management of these systems are discussed. Recommendations are made regarding improvement of the systems and the reduction of system sensitivity to the program factors.

  12. The deep space network, volume 18. [Deep Space Instrumentation Facility, Ground Communication Facility, and Network Control System

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The objectives, functions, and organization of the Deep Space Network are summarized. The Deep Space Instrumentation Facility, the Ground Communications Facility, and the Network Control System are described.

  13. Walking or Waiting? Topologies of the Breeding Ground in Malaria Control

    PubMed Central

    Lezaun, Javier

    2013-01-01

    Few places bear as much historical and scientific significance as the breeding ground, the accumulation of stagnant water where disease-carrying insects lay their eggs. Since the turn of the twentieth century, when mosquitoes of the Anopheles genus were identified as the vector of malaria transmission, these aquatic habitats have been a key object of epidemiological research and public health intervention against the disease. Yet the breeding ground can be incorporated into a number of different topologies, each implying a different spatialization of malaria and a distinct imagination of what kind of mosquito control is ‘doable'. A contemporary example of malaria control in Dar es Salaam, Tanzania, illuminates an essential tension between what we characterize as territorial and bionomic approaches to the breeding ground—that is, between control strategies premised on treating all mosquito habitats within a given region, and those that prioritize certain sites on the basis of their position within ecological networks. Each topology localizes the breeding ground by reference to a distinct set of relations, and thus advances an idiosyncratic understanding of what sort of research is worthwhile conducting and what kinds of intervention are sustainable. The multiple ways in which the breeding ground can become an object of research and action clarifies the role of topology as an infra-logic of public health, and makes explicit the politics implicit in efforts to bring different orders of the local to scale. PMID:25937707

  14. Factors controlling As and U in shallow ground water, southern Carson Desert, Nevada

    USGS Publications Warehouse

    Welch, A.H.; Lico, M.S.

    1998-01-01

    Unusually high As and U concentrations (> 100 ??g/L) are widespread in shallow ground water beneath the southern Carson Desert. The high concentrations, which locally exceed 1000 ??g/L, are of concern from a human health standpoint because the shallow ground water is used for domestic supply. Possible affects on wildlife are also of concern because the ground water flows into shallow lakes and marshes within wildlife refuges. Arsenic and U concentrations in ground water of the southern Carson Desert appear to be affected by evaporative concentration, redox reactions, and adsorption. The relation of these elements with Cl suggest that most of the high concentrations can be attributed to evaporative concentration of Carson River water, the primary source of recharge. Some ground water contains higher As and U concentrations that cannot be explained by evaporative concentration alone. Oxidation-reduction reactions, involving metal oxides and sedimentary-organic matter, appear to contribute As, U, inorganic C, Fe and Mn to the ground water. Arsenic in Fe-oxide was confirmed by chemical extraction and is consistent with laboratory adsorption studies. Uranium in both sedimentary-organic C and Fe-oxide coatings has been confirmed by fission tracks and petrographic examination. Arsenic concentrations in the ground water and chemical extracts of aquifer sediments are broadly consistent with adsorption as a control on some dissolved As concentrations. An apparent loss of As from some ground water as evaporative concentration proceeds is consistent with adsorption as a control on As. However, evidence for adsorption should be viewed with caution, because the adsorption model used values for the adsorbent that have not been shown to be valid for the aquifer sediments throughout the southern Carson Desert. Hydrologic and geochemical conditions in the Carson Desert are similar to other areas with high As and U concentrations in ground water, including the Salton Sea basin and

  15. Vibrating barrier: a novel device for the passive control of structures under ground motion

    PubMed Central

    Cacciola, P.; Tombari, A.

    2015-01-01

    A novel device, called vibrating barrier (ViBa), that aims to reduce the vibrations of adjacent structures subjected to ground motion waves is proposed. The ViBa is a structure buried in the soil and detached from surrounding buildings that is able to absorb a significant portion of the dynamic energy arising from the ground motion. The working principle exploits the dynamic interaction among vibrating structures due to the propagation of waves through the soil, namely the structure–soil–structure interaction. The underlying theoretical aspects of the novel control strategy are scrutinized along with its numerical modelling. Closed-form solutions are also derived to design the ViBa in the case of harmonic excitation. Numerical and experimental analyses are performed in order to investigate the efficiency of the device in mitigating the effects of ground motion waves on the structural response. A significant reduction in the maximum structural acceleration of 87% has been achieved experimentally. PMID:26345731

  16. Control and learning for intelligent mobility of unmanned ground vehicles in complex terrains

    NASA Astrophysics Data System (ADS)

    Trentini, M.; Beckman, B.; Digney, B.

    2005-05-01

    The Autonomous Intelligent Systems program at Defence R&D Canada-Suffield envisions autonomous systems contributing to decisive operations in the urban battle space. Creating effective intelligence for these systems demands advances in perception, world representation, navigation, and learning. In the land environment, these scientific areas have garnered much attention, while largely ignoring the problem of locomotion in complex terrain. This is a gap in robotics research, where sophisticated algorithms are needed to coordinate and control robotic locomotion in unknown, highly complex environments. Unlike traditional control problems, intuitive and systematic control tools for robotic locomotion do not readily exist thus limiting their practical application. This paper addresses the mobility problem for unmanned ground vehicles, defined here as the autonomous maneuverability of unmanned ground vehicles in unknown, highly complex environments. It discusses the progress and future direction of intelligent mobility research at Defence R&D Canada-Suffield and presents the research tools, topics and plans to address this critical research gap.

  17. Controls on ground water chemistry in the central Couloir Sud Rifain, Morocco.

    PubMed

    Benaabidate, Lahcen; Fryar, Alan E

    2010-01-01

    Irrigation, urbanization, and drought pose challenges for the sustainable use of ground water in the central Couloir sud rifain, a major agricultural region in north-central Morocco, which includes the cities of Fès and Meknès. The central Couloir is underlain by unconfined and confined carbonate aquifers that have suffered declines in hydraulic head and reductions in spring flow in recent decades. Previous studies have surveyed ground water flow and water quality in wells and springs but have not comprehensively addressed the chemistry of the regional aquifer system. Using graphical techniques and saturation index calculations, we infer that major ion chemistry is controlled (1) in the surficial aquifer by cation exchange, calcite dissolution, mixing with deep ground water, and possibly calcite precipitation and (2) in the confined aquifer and warm springs by calcite dissolution, dolomite dissolution, mixing with water that has dissolved gypsum and halite, and calcite precipitation. Analyses of (2)H and (18)O indicate that shallow ground water is affected by evaporation during recharge (either of infiltrating precipitation or return flow), whereas deep ground water is sustained by meteoric recharge with little evaporation. Mechanisms of recharge and hydrochemical evolution are broadly consistent with those delineated for similar regional aquifer systems elsewhere in Morocco and in southern Spain. PMID:19210561

  18. Fracture control of ground water flow and water chemistry in a rock aquitard

    USGS Publications Warehouse

    Eaton, T.T.; Anderson, M.P.; Bradbury, K.R.

    2007-01-01

    There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the aquitard are more complex than previously believed. Similar conceptual models, based on regional observations and recently emerging principles of mechanical stratigraphy in heterogeneous sedimentary rocks, have previously been applied only to aquifers, but we show that they are potentially applicable to aquitards. The major elements of this conceptual model, which is based on detailed information from two sites in the Maquoketa Formation in southeastern Wisconsin, include orders of magnitude contrast between hydraulic diffusivity (K/Ss) of fractured zones and relatively intact aquitard rock matrix, laterally extensive bedding-plane fracture zones extending over distances of over 10 km, very low vertical hydraulic conductivity of thick shale-rich intervals of the aquitard, and a vertical hydraulic head profile controlled by a lateral boundary at the aquitard subcrop, where numerous surface water bodies dominate the shallow aquifer system. Results from a 3D numerical flow model based on this conceptual model are consistent with field observations, which did not fit the typical conceptual model of strictly vertical flow through an aquitard. The 3D flow through an aquitard has implications for predicting ground water flow and for planning and protecting water supplies. ?? 2007 National Ground Water Association.

  19. Is Ground Cover Vegetation an Effective Biological Control Enhancement Strategy against Olive Pests?

    PubMed Central

    Paredes, Daniel; Cayuela, Luis; Gurr, Geoff M.; Campos, Mercedes

    2015-01-01

    Ground cover vegetation is often added or allowed to generate to promote conservation biological control, especially in perennial crops. Nevertheless, there is inconsistent evidence of its effectiveness, with studies reporting positive, nil or negative effects on pest control. This might arise from differences between studies at the local scale (e.g. orchard management and land use history), the landscape context (e.g. presence of patches of natural or semi-natural vegetation near the focal orchard), or regional factors, particularly climate in the year of the study. Here we present the findings from a long-term regional monitoring program conducted on four pest species (Bactrocera oleae, Prays oleae, Euphyllura olivina, Saissetia oleae) in 2,528 olive groves in Andalusia (Spain) from 2006 to 2012. Generalized linear mixed effect models were used to analyze the effect of ground cover on different response variables related to pest abundance, while accounting for variability at the local, landscape and regional scales. There were small and inconsistent effects of ground cover on the abundance of pests whilst local, landscape and regional variability explained a large proportion of the variability in pest response variables. This highlights the importance of local and landscape-related variables in biological control and the potential effects that might emerge from their interaction with practices, such as groundcover vegetation, implemented to promote natural enemy activity. The study points to perennial vegetation close to the focal crop as a promising alternative strategy for conservation biological control that should receive more attention. PMID:25646778

  20. Obstacle negotiation control for a mobile robot suspended on overhead ground wires by optoelectronic sensors

    NASA Astrophysics Data System (ADS)

    Zheng, Li; Yi, Ruan

    2009-11-01

    Power line inspection and maintenance already benefit from developments in mobile robotics. This paper presents mobile robots capable of crossing obstacles on overhead ground wires. A teleoperated robot realizes inspection and maintenance tasks on power transmission line equipment. The inspection robot is driven by 11 motor with two arms, two wheels and two claws. The inspection robot is designed to realize the function of observation, grasp, walk, rolling, turn, rise, and decline. This paper is oriented toward 100% reliable obstacle detection and identification, and sensor fusion to increase the autonomy level. An embedded computer based on PC/104 bus is chosen as the core of control system. Visible light camera and thermal infrared Camera are both installed in a programmable pan-and-tilt camera (PPTC) unit. High-quality visual feedback rapidly becomes crucial for human-in-the-loop control and effective teleoperation. The communication system between the robot and the ground station is based on Mesh wireless networks by 700 MHz bands. An expert system programmed with Visual C++ is developed to implement the automatic control. Optoelectronic laser sensors and laser range scanner were installed in robot for obstacle-navigation control to grasp the overhead ground wires. A novel prototype with careful considerations on mobility was designed to inspect the 500KV power transmission lines. Results of experiments demonstrate that the robot can be applied to execute the navigation and inspection tasks.

  1. Is ground cover vegetation an effective biological control enhancement strategy against olive pests?

    PubMed

    Paredes, Daniel; Cayuela, Luis; Gurr, Geoff M; Campos, Mercedes

    2015-01-01

    Ground cover vegetation is often added or allowed to generate to promote conservation biological control, especially in perennial crops. Nevertheless, there is inconsistent evidence of its effectiveness, with studies reporting positive, nil or negative effects on pest control. This might arise from differences between studies at the local scale (e.g. orchard management and land use history), the landscape context (e.g. presence of patches of natural or semi-natural vegetation near the focal orchard), or regional factors, particularly climate in the year of the study. Here we present the findings from a long-term regional monitoring program conducted on four pest species (Bactrocera oleae, Prays oleae, Euphyllura olivina, Saissetia oleae) in 2,528 olive groves in Andalusia (Spain) from 2006 to 2012. Generalized linear mixed effect models were used to analyze the effect of ground cover on different response variables related to pest abundance, while accounting for variability at the local, landscape and regional scales. There were small and inconsistent effects of ground cover on the abundance of pests whilst local, landscape and regional variability explained a large proportion of the variability in pest response variables. This highlights the importance of local and landscape-related variables in biological control and the potential effects that might emerge from their interaction with practices, such as groundcover vegetation, implemented to promote natural enemy activity. The study points to perennial vegetation close to the focal crop as a promising alternative strategy for conservation biological control that should receive more attention. PMID:25646778

  2. Review of Ground Systems Development and Operations (GSDO) Tools for Verifying Command and Control Software

    NASA Technical Reports Server (NTRS)

    Aguilar, Michael L.; Bonanne, Kevin H.; Favretto, Jeffrey A.; Jackson, Maddalena M.; Jones, Stephanie L.; Mackey, Ryan M.; Sarrel, Marc A.; Simpson, Kimberly A.

    2014-01-01

    The Exploration Systems Development (ESD) Standing Review Board (SRB) requested the NASA Engineering and Safety Center (NESC) conduct an independent review of the plan developed by Ground Systems Development and Operations (GSDO) for identifying models and emulators to create a tool(s) to verify their command and control software. The NESC was requested to identify any issues or weaknesses in the GSDO plan. This document contains the outcome of the NESC review.

  3. Shuttle Payload Ground Command and Control: An Experiment Implementation Combustion Module-2 Software Development, STS-107

    NASA Technical Reports Server (NTRS)

    Carek, David Andrew

    2003-01-01

    This presentation covers the design of a command and control architecture developed by the author for the Combustion Module-2 microgravity experiment, which flew aboard the STS-107 Shuttle mission, The design was implemented to satisfy a hybrid network that utilized TCP/IP for both the onboard segment and ground segment, with an intermediary unreliable transport for the space to ground segment. With the infusion of Internet networking technologies into Space Shuttle, Space Station, and spacecraft avionics systems, comes the need for robust methodologies for ground command and control. Considerations of high bit error links, and unreliable transport over intermittent links must be considered in such systems. Internet protocols applied to these systems, coupled with the appropriate application layer protections, can provide adequate communication architectures for command and control. However, there are inherent limitations and additional complexities added by the use of Internet protocols that must be considered during the design. This presentation will discuss the rationale for the: framework and protocol algorithms developed by the author. A summary of design considerations, implantation issues, and learned lessons will be will be presented. A summary of mission results using this communications architecture will be presented. Additionally, areas of further needed investigation will be identified.

  4. Interior noise control ground test studies for advanced turboprop aircraft applications

    NASA Technical Reports Server (NTRS)

    Simpson, Myles A.; Cannon, Mark R.; Burge, Paul L.; Boyd, Robert P.

    1989-01-01

    The measurement and analysis procedures are documented, and the results of interior noise control ground tests conducted on a DC-9 aircraft test section are summarized. The objectives of these tests were to study the fuselage response characteristics of treated and untreated aircraft with aft-mount advanced turboprop engines and to analyze the effectiveness of selected noise control treatments in reducing passenger cabin noise on these aircraft. The results of fuselage structural mode surveys, cabin cavity surveys and sound intensity surveys are presented. The performance of various structural and cabin sidewall treatments is assessed, based on measurements of the resulting interior noise levels under simulated advanced turboprop excitation.

  5. Criteria for Side-Force Control in Air-to-Ground Target Acquisition and Tracking

    NASA Technical Reports Server (NTRS)

    Sammonds, Robert I.; McNeill, Walter E.; Bunnell, John W.

    1982-01-01

    A moving-base simulator experiment conducted at Ames Research Center demonstrated that a wings-level-turn control mode improved flying qualities for air-to-ground weapons delivery compared with those of a conventional aircraft. Evaluations of criteria for dynamic response for this system have shown that pilot ratings correlate well with equivalent time constant of the initial response and with system bandwidth. Ranges of this time constant, as well as digital-system transport delays and lateral-acceleration control authorities that encompassed level 1 through level 3 handling qualities, were determined.

  6. The Next Generation of Ground Operations Command and Control; Scripting in C Sharp and Visual Basic

    NASA Technical Reports Server (NTRS)

    Ritter, George; Pedoto, Ramon

    2010-01-01

    This slide presentation reviews the use of scripting languages in Ground Operations Command and Control. It describes the use of scripting languages in a historical context, the advantages and disadvantages of scripts. It describes the Enhanced and Redesigned Scripting (ERS) language, that was designed to combine the features of a scripting language and the graphical and IDE richness of a programming language with the utility of scripting languages. ERS uses the Microsoft Visual Studio programming environment and offers custom controls that enable an ERS developer to extend the Visual Basic and C sharp language interface with the Payload Operations Integration Center (POIC) telemetry and command system.

  7. Proceedings of 13th international conference on ground control in mining

    SciTech Connect

    Peng, S.S.

    1994-01-01

    The Proceedings of the 13th International Conference on Ground Control in Mining held August 2-4, 1994 is presented. The papers include information on bolting and entry stability; coal pillars; longwall overburden movement; longwall roof control, production and maintenance aids; longwall shield selection; longwall tailgate support; mining operations, mine and support design; multiple seam mining; roof/rib quality determination; stress determination; and surface subsidence. Separate abstracts and indexing were prepared for each paper for inclusion in the Energy Science and Technology Database.

  8. Evaluation of SAR Data as Source of Ground Control Information: First Results

    NASA Astrophysics Data System (ADS)

    Vassilaki, D. I.; Ioannidis, C.; Stamos, A. A.

    2013-05-01

    The high resolution imaging modes of modern SAR sensors has made SAR data compatible with optical images. SAR data offers various capabilities which can enhance the geometric correction process of optical images (accurate, direct and ground-independent georeferencing capabilities and global DEM products). In this paper the first results of an on-going study on the evaluation of SAR data as source of ground control information for the georeferencing of optical images are presented. The georeferencing of optical images using SAR data is in fact a co-registration problem which involves multimodal, mutitemporal, and multiresolution data. And although 2D transformations have proved to be insufficient for the georeferencing process, as they can not account for the distortions due to terrain, quite a few approaches on the registration of optical to SAR data using 2D-2D transformations can still be found in the literature. In this paper the performance of 2D-2D transformations is compared to the 3D-2D projective transformation over a greater area of Earth's surface with arbitrary terrain type. Two alternative forms of ground control information are used: points and FFLFs. The accuracy of the computed results is obtained using independent CPs and it is compared to the geolocation accuracy specification of the optical image, as well as to the accuracy of exhaustive georeferencing done by third parties.

  9. Scaled Composites' Doug Shane examines the screen of his ground control station during tests in New

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Scaled Composites' Doug Shane examines the screen of his ground control station during tests in New Mexico. Shane used this configuration as the ground control station to remotely pilot the Proteus aircraft during a NASA sponsored series of test flights. The unique Proteus aircraft served as a test bed for NASA-sponsored flight tests designed to validate collision-avoidance technologies proposed for uninhabited aircraft. The tests, flown over southern New Mexico in March, 2002, used the Proteus as a surrogate uninhabited aerial vehicle (UAV) while three other aircraft flew toward the Proteus from various angles on simulated collision courses. Radio-based 'detect, see and avoid' equipment on the Proteus successfully detected the other aircraft and relayed that information to a remote pilot on the ground at Las Cruces Airport. The pilot then transmitted commands to the Proteus to maneuver it away from the potential collisions. The flight demonstration, sponsored by NASA Dryden Flight Research Center, New Mexico State University, Scaled Composites, the U.S. Navy and Modern Technology Solutions, Inc., were intended to demonstrate that UAVs can be flown safely and compatibly in the same skies as piloted aircraft.

  10. Fracture control of ground water flow and water chemistry in a rock aquitard.

    PubMed

    Eaton, Timothy T; Anderson, Mary P; Bradbury, Kenneth R

    2007-01-01

    There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the aquitard are more complex than previously believed. Similar conceptual models, based on regional observations and recently emerging principles of mechanical stratigraphy in heterogeneous sedimentary rocks, have previously been applied only to aquifers, but we show that they are potentially applicable to aquitards. The major elements of this conceptual model, which is based on detailed information from two sites in the Maquoketa Formation in southeastern Wisconsin, include orders of magnitude contrast between hydraulic diffusivity (K/S(s)) of fractured zones and relatively intact aquitard rock matrix, laterally extensive bedding-plane fracture zones extending over distances of over 10 km, very low vertical hydraulic conductivity of thick shale-rich intervals of the aquitard, and a vertical hydraulic head profile controlled by a lateral boundary at the aquitard subcrop, where numerous surface water bodies dominate the shallow aquifer system. Results from a 3D numerical flow model based on this conceptual model are consistent with field observations, which did not fit the typical conceptual model of strictly vertical flow through an aquitard. The 3D flow through an aquitard has implications for predicting ground water flow and for planning and protecting water supplies. PMID:17760586

  11. Ground-level ozone influenced by circadian control of isoprene emissions

    NASA Astrophysics Data System (ADS)

    Hewitt, C. N.; Ashworth, K.; Boynard, A.; Guenther, A.; Langford, B.; MacKenzie, A. R.; Misztal, P. K.; Nemitz, E.; Owen, S. M.; Possell, M.; Pugh, T. A. M.; Ryan, A. C.; Wild, O.

    2011-10-01

    The volatile organic compound isoprene is produced by many plant species, and provides protection against biotic and abiotic stresses. Globally, isoprene emissions from plants are estimated to far exceed anthropogenic emissions of volatile organic compounds. Once in the atmosphere, isoprene reacts rapidly with hydroxyl radicals to form peroxy radicals, which can react with nitrogen oxides to form ground-level ozone. Here, we use canopy-scale measurements of isoprene fluxes from two tropical ecosystems in Malaysia--a rainforest and an oil palm plantation--and three models of atmospheric chemistry to explore the effects of isoprene fluxes on ground-level ozone. We show that isoprene emissions in these ecosystems are under circadian control on the canopy scale, particularly in the oil palm plantation. As a result, these ecosystems emit less isoprene than present emissions models predict. Using local-, regional- and global-scale models of atmospheric chemistry and transport, we show that accounting for circadian control of isoprene emissions brings model predictions of ground-level ozone into better agreement with measurements, especially in isoprene-sensitive regions of the world.

  12. Integrated Vehicle Ground Vibration Testing in Support of Launch Vehicle Loads and Controls Analysis

    NASA Technical Reports Server (NTRS)

    Askins, Bruce R.; Davis, Susan R.; Salyer, Blaine H.; Tuma, Margaret L.

    2008-01-01

    All structural systems possess a basic set of physical characteristics unique to that system. These unique physical characteristics include items such as mass distribution and damping. When specified, they allow engineers to understand and predict how a structural system behaves under given loading conditions and different methods of control. These physical properties of launch vehicles may be predicted by analysis or measured by certain types of tests. Generally, these properties are predicted by analysis during the design phase of a launch vehicle and then verified by testing before the vehicle becomes operational. A ground vibration test (GVT) is intended to measure by test the fundamental dynamic characteristics of launch vehicles during various phases of flight. During the series of tests, properties such as natural frequencies, mode shapes, and transfer functions are measured directly. These data will then be used to calibrate loads and control systems analysis models for verifying analyses of the launch vehicle. NASA manned launch vehicles have undergone ground vibration testing leading to the development of successful launch vehicles. A GVT was not performed on the inaugural launch of the unmanned Delta III which was lost during launch. Subsequent analyses indicated had a GVT been performed, it would have identified instability issues avoiding loss of the vehicle. This discussion will address GVT planning, set-up, execution and analyses, for the Saturn and Shuttle programs, and will also focus on the current and on-going planning for the Ares I and V Integrated Vehicle Ground Vibration Test (IVGVT).

  13. Ground Control Point - Wireless System Network for UAV-based environmental monitoring applications

    NASA Astrophysics Data System (ADS)

    Mejia-Aguilar, Abraham

    2016-04-01

    In recent years, Unmanned Aerial Vehicles (UAV) have seen widespread civil applications including usage for survey and monitoring services in areas such as agriculture, construction and civil engineering, private surveillance and reconnaissance services and cultural heritage management. Most aerial monitoring services require the integration of information acquired during the flight (such as imagery) with ground-based information (such as GPS information or others) for improved ground truth validation. For example, to obtain an accurate 3D and Digital Elevation Model based on aerial imagery, it is necessary to include ground-based information of coordinate points, which are normally acquired with surveying methods based on Global Position Systems (GPS). However, GPS surveys are very time consuming and especially for longer time series of monitoring data repeated GPS surveys are necessary. In order to improve speed of data collection and integration, this work presents an autonomous system based on Waspmote technologies build on single nodes interlinked in a Wireless Sensor Network (WSN) star-topology for ground based information collection and later integration with surveying data obtained by UAV. Nodes are designed to be visible from the air, to resist extreme weather conditions with low-power consumption. Besides, nodes are equipped with GPS as well as Inertial Measurement Unit (IMU), accelerometer, temperature and soil moisture sensors and thus provide significant advantages in a broad range of applications for environmental monitoring. For our purpose, the WSN transmits the environmental data with 3G/GPRS to a database on a regular time basis. This project provides a detailed case study and implementation of a Ground Control Point System Network for UAV-based vegetation monitoring of dry mountain grassland in the Matsch valley, Italy.

  14. Ground-based rodent control in a remote Hawaiian rainforest on Maui

    USGS Publications Warehouse

    Malcolm, T.R.; Swinnerton, K.J.; Groombridge, J.J.; Sparklin, B.D.; Brosius, C.N.; Vetter, J.P.; Foster, J.T.

    2008-01-01

    Effective control of introduced mammalian predators is essential to the recovery of native bird species in Hawai'i. Between August 1996 and December 2004, introduced rodents were controlled within three home ranges of the Po'ouli Melamprosops phaeosoma, a critically endangered Hawaiian honeycreeper. Rats were controlled using a combination of ground-based rodenticide (0.005% diphacinone) application and snap traps. Beginning in August 2001, we monitored the effectiveness of these rodent control efforts. Relative abundances of Black Rats Rattus rattus and Polynesian Rats R. exulans were measured in each of five snap-trapping grids seven times over a 35-month period. Rat populations decreased inside of the rodent control areas, but control effectiveness differed between rat species. During the first year of monitoring, target control levels for R. rattus were consistently achieved in only one of the rodent control areas. Control techniques were refined in areas failing to meet targets. Subsequently, we achieved target control levels for R. rattus more consistently in all three rodent control areas. However, relative abundances of R. exulans did not differ between rodent control and reference areas, indicating that our rodent control techniques were insufficient to reduce population levels of this species. These findings signify a need for further improvement of rodent control methods in Hawai'i, especially for Polynesian Rats, and demonstrate the critical importance of periodic monitoring of the response of rodent populations to management. In the future, managers may need to design rodent control operations targeting R. rattus and R. exulans independently to achieve best results.

  15. Robust H∞ output-feedback control for path following of autonomous ground vehicles

    NASA Astrophysics Data System (ADS)

    Hu, Chuan; Jing, Hui; Wang, Rongrong; Yan, Fengjun; Chadli, Mohammed

    2016-03-01

    This paper presents a robust H∞ output-feedback control strategy for the path following of autonomous ground vehicles (AGVs). Considering the vehicle lateral velocity is usually hard to measure with low cost sensor, a robust H∞ static output-feedback controller based on the mixed genetic algorithms (GA)/linear matrix inequality (LMI) approach is proposed to realize the path following without the information of the lateral velocity. The proposed controller is robust to the parametric uncertainties and external disturbances, with the parameters including the tire cornering stiffness, vehicle longitudinal velocity, yaw rate and road curvature. Simulation results based on CarSim-Simulink joint platform using a high-fidelity and full-car model have verified the effectiveness of the proposed control approach.

  16. Tug fleet and ground operations schedules and controls. Volume 2: part 2, addenda

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The results of a study to assess the tug safing requirements at postlanding are presented. The study considered the normal (green light) conditions from orbiter landing to completion of preparations for the next launch. Normal tug ground turnaround operations include handling and transportation activities and the performance of inspections, tests, and checkout functions. These activities dictate that hazards to ground personnel, the tug, GSE, facilities, and ecology be reduced to the lowest practical level consistent with program objectives, cost, and schedules. During flight operations, the tug contains energy sources that constitute potential hazards but are required for mission accomplishment. These potential hazards have been reduced to an acceptable level for flight operation by design features and by providing for control of energy sources.

  17. Optical Communication System for Remote Monitoring and Adaptive Control of Distributed Ground Sensors Exhibiting Collective Intelligence

    SciTech Connect

    Cameron, S.M.; Stantz, K.M.; Trahan, M.W.; Wagner, J.S.

    1998-11-01

    Comprehensive management of the battle-space has created new requirements in information management, communication, and interoperability as they effect surveillance and situational awareness. The objective of this proposal is to expand intelligent controls theory to produce a uniquely powerful implementation of distributed ground-based measurement incorporating both local collective behavior, and interoperative global optimization for sensor fusion and mission oversight. By using a layered hierarchal control architecture to orchestrate adaptive reconfiguration of autonomous robotic agents, we can improve overall robustness and functionality in dynamic tactical environments without information bottlenecks. In this concept, each sensor is equipped with a miniaturized optical reflectance modulator which is interactively monitored as a remote transponder using a covert laser communication protocol from a remote mothership or operative. Robot data-sharing at the ground level can be leveraged with global evaluation criteria, including terrain overlays and remote imaging data. Information sharing and distributed intelli- gence opens up a new class of remote-sensing applications in which small single-function autono- mous observers at the local level can collectively optimize and measure large scale ground-level signals. AS the need for coverage and the number of agents grows to improve spatial resolution, cooperative behavior orchestrated by a global situational awareness umbrella will be an essential ingredient to offset increasing bandwidth requirements within the net. A system of the type described in this proposal will be capable of sensitively detecting, tracking, and mapping spatial distributions of measurement signatures which are non-stationary or obscured by clutter and inter- fering obstacles by virtue of adaptive reconfiguration. This methodology could be used, for example, to field an adaptive ground-penetrating radar for detection of underground structures in

  18. Design and implementation of a microcomputer-based user interface controller for bursted data communications satellite ground terminals

    NASA Technical Reports Server (NTRS)

    Shalkhauser, Mary Jo W.

    1988-01-01

    The NASA Lewis Research Center is developing a laboratory-based satellite communications test bed for evaluation of state-of-the-art communications hardware and systems. Most of the digital components of the ground terminals are being constructed in-house at NASA Lewis. One of the ground terminal subsystems, the user interface controller, controls the connection and disconnection of all users to the communication network. The role of the user interface controller in the ground terminal is described and the design and implementation of the microcomputer-based subsystem is discussed.

  19. Flight validation of ground-based assessment for control power requirements at high angles of attack

    NASA Technical Reports Server (NTRS)

    Ogburn, Marilyn E.; Ross, Holly M.; Foster, John V.; Pahle, Joseph W.; Sternberg, Charles A.; Traven, Ricardo; Lackey, James B.; Abbott, Troy D.

    1994-01-01

    A review is presented in viewgraph format of an ongoing NASA/U.S. Navy study to determine control power requirements at high angles of attack for the next generation high-performance aircraft. This paper focuses on recent flight test activities using the NASA High Alpha Research Vehicle (HARV), which are intended to validate results of previous ground-based simulation studies. The purpose of this study is discussed, and the overall program structure, approach, and objectives are described. Results from two areas of investigation are presented: (1) nose-down control power requirements and (2) lateral-directional control power requirements. Selected results which illustrate issues and challenges that are being addressed in the study are discussed including test methodology, comparisons between simulation and flight, and general lessons learned.

  20. Controls on Coral-Ground Development along the Northern Mesoamerican Reef Tract

    PubMed Central

    Rodríguez-Martínez, Rosa E.; Jordán-Garza, Adán G.; Maldonado, Miguel A.; Blanchon, Paul

    2011-01-01

    Coral-grounds are reef communities that colonize rocky substratum but do not form framework or three-dimensional reef structures. To investigate why, we used video transects and underwater photography to determine the composition, structure and status of a coral-ground community located on the edge of a rocky terrace in front of a tourist park, Xcaret, in the northern Mesoamerican Reef tract, Mexico. The community has a relatively low coral, gorgonian and sponge cover (<10%) and high algal cover (>40%). We recorded 23 species of Scleractinia, 14 species of Gorgonacea and 30 species of Porifera. The coral community is diverse but lacks large coral colonies, being dominated instead by small, sediment-tolerant, and brooding species. In these small colonies, the abundance of potentially lethal interactions and partial mortality is high but decreases when colonies are larger than 40 cm. Such characteristics are consistent with an environment control whereby storm waves periodically remove larger colonies and elevate sediment flux. The community only survives these storm conditions due to its slope-break location, which ensures lack of burial and continued local recruitment. A comparison with similar coral-ground communities in adjacent areas suggests that the narrow width of the rock terrace hinders sediment stabilization, thereby ensuring that communities cannot escape bottom effects and develop into three-dimensional reef structures on geological time scales. PMID:22194839

  1. Resetting transcription factor control circuitry toward ground-state pluripotency in human.

    PubMed

    Takashima, Yasuhiro; Guo, Ge; Loos, Remco; Nichols, Jennifer; Ficz, Gabriella; Krueger, Felix; Oxley, David; Santos, Fatima; Clarke, James; Mansfield, William; Reik, Wolf; Bertone, Paul; Smith, Austin

    2014-09-11

    Current human pluripotent stem cells lack the transcription factor circuitry that governs the ground state of mouse embryonic stem cells (ESC). Here, we report that short-term expression of two components, NANOG and KLF2, is sufficient to ignite other elements of the network and reset the human pluripotent state. Inhibition of ERK and protein kinase C sustains a transgene-independent rewired state. Reset cells self-renew continuously without ERK signaling, are phenotypically stable, and are karyotypically intact. They differentiate in vitro and form teratomas in vivo. Metabolism is reprogrammed with activation of mitochondrial respiration as in ESC. DNA methylation is dramatically reduced and transcriptome state is globally realigned across multiple cell lines. Depletion of ground-state transcription factors, TFCP2L1 or KLF4, has marginal impact on conventional human pluripotent stem cells but collapses the reset state. These findings demonstrate feasibility of installing and propagating functional control circuitry for ground-state pluripotency in human cells. PMID:25215486

  2. Controls on coral-ground development along the northern Mesoamerican Reef tract.

    PubMed

    Rodríguez-Martínez, Rosa E; Jordán-Garza, Adán G; Maldonado, Miguel A; Blanchon, Paul

    2011-01-01

    Coral-grounds are reef communities that colonize rocky substratum but do not form framework or three-dimensional reef structures. To investigate why, we used video transects and underwater photography to determine the composition, structure and status of a coral-ground community located on the edge of a rocky terrace in front of a tourist park, Xcaret, in the northern Mesoamerican Reef tract, Mexico. The community has a relatively low coral, gorgonian and sponge cover (<10%) and high algal cover (>40%). We recorded 23 species of Scleractinia, 14 species of Gorgonacea and 30 species of Porifera. The coral community is diverse but lacks large coral colonies, being dominated instead by small, sediment-tolerant, and brooding species. In these small colonies, the abundance of potentially lethal interactions and partial mortality is high but decreases when colonies are larger than 40 cm. Such characteristics are consistent with an environment control whereby storm waves periodically remove larger colonies and elevate sediment flux. The community only survives these storm conditions due to its slope-break location, which ensures lack of burial and continued local recruitment. A comparison with similar coral-ground communities in adjacent areas suggests that the narrow width of the rock terrace hinders sediment stabilization, thereby ensuring that communities cannot escape bottom effects and develop into three-dimensional reef structures on geological time scales. PMID:22194839

  3. Mission specification and control for unmanned aerial and ground vehicles for indoor target discovery and tracking

    NASA Astrophysics Data System (ADS)

    Ulam, Patrick D.; Kira, Zsolt; Arkin, Ronald C.; Collins, Thomas R.

    2010-04-01

    This paper describes ongoing research by Georgia Tech into the challenges of tasking and controlling heterogonous teams of unmanned vehicles in mixed indoor/outdoor reconnaissance scenarios. We outline the tools and techniques necessary for an operator to specify, execute, and monitor such missions. The mission specification framework used for the purposes of intelligence gathering during mission execution are first demonstrated in simulations involving a team of a single autonomous rotorcraft and three ground-based robotic platforms. Preliminary results including robotic hardware in the loop are also provided.

  4. Hydrogeologic controls on ground-water and contaminant discharge to the Columbia River near the Hanford Townsite

    SciTech Connect

    Luttrell, S.P.; Newcomer, D.R.; Teel, S.S.; Vermeul, V.R.

    1992-11-01

    The purpose of this study is to quantify ground-water and contaminant discharge to the Columbia River in the Hanford Townsite vicinity. The primary objectives of the work are to: describe the hydrogeologic setting and controls on ground-water movement and contaminant discharge to the Columbia River; understand the river/aquifer relationship and its effects on contaminant discharge to the Columbia River; quantify the ground-water and contaminant mass discharge to the Columbia River; and provide data that may be useful for a three-dimensional model of ground-water flow and contaminant transport in the Hanford Townsite study area. The majority of ground-water contamination occurs within the unconfined aquifer; therefore, ground-water and contaminant discharge from the unconfined aquifer is the emphasis of this study. The period of study is primarily from June 1990 through March 1992.

  5. Form control in atmospheric pressure plasma processing of ground fused silica

    NASA Astrophysics Data System (ADS)

    Li, Duo; Wang, Bo; Xin, Qiang; Jin, Huiliang; Wang, Jun; Dong, Wenxia

    2014-08-01

    Atmospheric Pressure Plasma Processing (APPP) using inductively coupled plasma has demonstrated that it can achieve comparable removal rate on the optical surface of fused silica under the atmosphere pressure and has the advantage of inducing no sub-surface damage for its non-contact and chemical etching mechanism. APPP technology is a cost effective way, compared with traditional mechanical polishing, magnetorheological finishing and ion beam figuring. Thus, due to these advantages, this technology is being tested to fabricate large aperture optics of fused silica to help shorten the polishing time in optics fabrication chain. Now our group proposes to use inductively coupled plasma processing technology to fabricate ground surface of fused silica directly after the grinding stage. In this paper, form control method and several processing parameters are investigated to evaluate the removal efficiency and the surface quality, including the robustness of removal function, velocity control mode and tool path strategy. However, because of the high heat flux of inductively coupled plasma, the removal depth with time can be non-linear and the ground surface evolvement will be affected. The heat polishing phenomenon is founded. The value of surface roughness is reduced greatly, which is very helpful to reduce the time of follow-up mechanical polishing. Finally, conformal and deterministic polishing experiments are analyzed and discussed. The form error is less 3%, before and after the APPP, when 10μm depth of uniform removal is achieved on a 60×60mm ground fused silica. Also, a basin feature is fabricated to demonstrate the figuring capability and stability. Thus, APPP is a promising technology in processing the large aperture optics.

  6. Optimal Flight for Ground Noise Reduction in Helicopter Landing Approach: Optimal Altitude and Velocity Control

    NASA Astrophysics Data System (ADS)

    Tsuchiya, Takeshi; Ishii, Hirokazu; Uchida, Junichi; Gomi, Hiromi; Matayoshi, Naoki; Okuno, Yoshinori

    This study aims to obtain the optimal flights of a helicopter that reduce ground noise during landing approach with an optimization technique, and to conduct flight tests for confirming the effectiveness of the optimal solutions. Past experiments of Japan Aerospace Exploration Agency (JAXA) show that the noise of a helicopter varies significantly according to its flight conditions, especially depending on the flight path angle. We therefore build a simple noise model for a helicopter, in which the level of the noise generated from a point sound source is a function only of the flight path angle. Using equations of motion for flight in a vertical plane, we define optimal control problems for minimizing noise levels measured at points on the ground surface, and obtain optimal controls for specified initial altitudes, flight constraints, and wind conditions. The obtained optimal flights avoid the flight path angle which generates large noise and decrease the flight time, which are different from conventional flight. Finally, we verify the validity of the optimal flight patterns through flight experiments. The actual flights following the optimal paths resulted in noise reduction, which shows the effectiveness of the optimization.

  7. Reconstructing 3D coastal cliffs from airborne oblique photographs without ground control points

    NASA Astrophysics Data System (ADS)

    Dewez, T. J. B.

    2014-05-01

    Coastal cliff collapse hazard assessment requires measuring cliff face topography at regular intervals. Terrestrial laser scanner techniques have proven useful so far but are expensive to use either through purchasing the equipment or through survey subcontracting. In addition, terrestrial laser surveys take time which is sometimes incompatible with the time during with the beach is accessible at low-tide. By comparison, structure from motion techniques (SFM) are much less costly to implement, and if airborne, acquisition of several kilometers of coastline can be done in a matter of minutes. In this paper, the potential of GPS-tagged oblique airborne photographs and SFM techniques is examined to reconstruct chalk cliff dense 3D point clouds without Ground Control Points (GCP). The focus is put on comparing the relative 3D point of views reconstructed by Visual SFM with their synchronous Solmeta Geotagger Pro2 GPS locations using robust estimators. With a set of 568 oblique photos, shot from the open door of an airplane with a triplet of synchronized Nikon D7000, GPS and SFM-determined view point coordinates converge to X: ±31.5 m; Y: ±39.7 m; Z: ±13.0 m (LE66). Uncertainty in GPS position affects the model scale, angular attitude of the reference frame (the shoreline ends up tilted by 2°) and absolute positioning. Ground Control Points cannot be avoided to orient such models.

  8. A ground track control algorithm for the Topographic Mapping Laser Altimeter (TMLA)

    NASA Technical Reports Server (NTRS)

    Blaes, V.; Mcintosh, R.; Roszman, L.; Cooley, J.

    1993-01-01

    The results of an analysis of an algorithm that will provide autonomous onboard orbit control using orbits determined with Global Positioning System (GPS) data. The algorithm uses the GPS data to (1) compute the ground track error relative to a fixed longitude grid, and (2) determine the altitude adjustment required to correct the longitude error. A program was written on a personal computer (PC) to test the concept for numerous altitudes and values of solar flux using a simplified orbit model including only the J sub 2 zonal harmonic and simple orbit decay computations. The algorithm was then implemented in a precision orbit propagation program having a full range of perturbations. The analysis showed that, even with all perturbations (including actual time histories of solar flux variation), the algorithm could effectively control the spacecraft ground track and yield more than 99 percent Earth coverage in the time required to complete one coverage cycle on the fixed grid (220 to 230 days depending on altitude and overlap allowance).

  9. Validation of space/ground antenna control algorithms using a computer-aided design tool

    NASA Technical Reports Server (NTRS)

    Gantenbein, Rex E.

    1995-01-01

    The validation of the algorithms for controlling the space-to-ground antenna subsystem for Space Station Alpha is an important step in assuring reliable communications. These algorithms have been developed and tested using a simulation environment based on a computer-aided design tool that can provide a time-based execution framework with variable environmental parameters. Our work this summer has involved the exploration of this environment and the documentation of the procedures used to validate these algorithms. We have installed a variety of tools in a laboratory of the Tracking and Communications division for reproducing the simulation experiments carried out on these algorithms to verify that they do meet their requirements for controlling the antenna systems. In this report, we describe the processes used in these simulations and our work in validating the tests used.

  10. Definition of ground test for verification of large space structure control

    NASA Technical Reports Server (NTRS)

    Glaese, John R.

    1994-01-01

    Under this contract, the Large Space Structure Ground Test Verification (LSSGTV) Facility at the George C. Marshall Space Flight Center (MSFC) was developed. Planning in coordination with NASA was finalized and implemented. The contract was modified and extended with several increments of funding to procure additional hardware and to continue support for the LSSGTV facility. Additional tasks were defined for the performance of studies in the dynamics, control and simulation of tethered satellites. When the LSSGTV facility development task was completed, support and enhancement activities were funded through a new competitive contract won by LCD. All work related to LSSGTV performed under NAS8-35835 has been completed and documented. No further discussion of these activities will appear in this report. This report summarizes the tether dynamics and control studies performed.

  11. The visual control of stability in children and adults: postural readjustments in a ground optical flow.

    PubMed

    Baumberger, Bernard; Isableu, Brice; Flückiger, Michelangelo

    2004-11-01

    The aim of this research was to analyse the development of postural reactions to approaching (AOF) and receding (ROF) ground rectilinear optical flows. Optical flows were shaped by a pattern of circular spots of light projected on the ground surface by a texture flow generator. The geometrical structure of the projected scenes corresponded to the spatial organisation of visual flows encountered in open outdoor settings. Postural readjustments of 56 children, ranging from 7 to 11 years old, and 12 adults were recorded by the changes of the centre of foot pressure (CoP) on a force platform during 44-s exposures to the moving texture. Before and after the optical flows exposure, a 24-s motionless texture served as a reference condition. Effect of ground rectilinear optical flows on postural control development was assessed by analysing sway latencies (SL), stability performances and postural orientation. The main results that emerge from this experiment show that postural responses are directionally specific to optical flow pattern and that they vary as a function of the motion onset and offset. Results showed that greater developmental changes in postural control occurred in an AOF (both at the onset and offset of the optical flow) than in an ROF. Onset of an approaching flow induced postural instability, canonical shifts in postural orientation and long latencies in children which were stronger than in the receding flow. This pattern of responses evolved with age towards an improvement in stability performances and shorter SL. The backward decreasing shift of the CoP in children evolved in adults towards forward postural tilt, i.show $132#e. in the opposite direction of the texture's motion. Offset of an AOF motion induced very short SL in children (which became longer in adult subjects), strong postural instability, but weaker shift of orientation compared to the receding one. Postural stability improved and orientation shift evolved to forward inclinations with

  12. Distributed pheromone-based swarming control of unmanned air and ground vehicles for RSTA

    NASA Astrophysics Data System (ADS)

    Sauter, John A.; Mathews, Robert S.; Yinger, Andrew; Robinson, Joshua S.; Moody, John; Riddle, Stephanie

    2008-04-01

    The use of unmanned vehicles in Reconnaissance, Surveillance, and Target Acquisition (RSTA) applications has received considerable attention recently. Cooperating land and air vehicles can support multiple sensor modalities providing pervasive and ubiquitous broad area sensor coverage. However coordination of multiple air and land vehicles serving different mission objectives in a dynamic and complex environment is a challenging problem. Swarm intelligence algorithms, inspired by the mechanisms used in natural systems to coordinate the activities of many entities provide a promising alternative to traditional command and control approaches. This paper describes recent advances in a fully distributed digital pheromone algorithm that has demonstrated its effectiveness in managing the complexity of swarming unmanned systems. The results of a recent demonstration at NASA's Wallops Island of multiple Aerosonde Unmanned Air Vehicles (UAVs) and Pioneer Unmanned Ground Vehicles (UGVs) cooperating in a coordinated RSTA application are discussed. The vehicles were autonomously controlled by the onboard digital pheromone responding to the needs of the automatic target recognition algorithms. UAVs and UGVs controlled by the same pheromone algorithm self-organized to perform total area surveillance, automatic target detection, sensor cueing, and automatic target recognition with no central processing or control and minimal operator input. Complete autonomy adds several safety and fault tolerance requirements which were integrated into the basic pheromone framework. The adaptive algorithms demonstrated the ability to handle some unplanned hardware failures during the demonstration without any human intervention. The paper describes lessons learned and the next steps for this promising technology.

  13. A framework for the natural-language-perception-based creative control of unmanned ground vehicles

    NASA Astrophysics Data System (ADS)

    Ghaffari, Masoud; Liao, Xiaoqun; Hall, Ernest L.

    2004-09-01

    Mobile robots must often operate in an unstructured environment cluttered with obstacles and with many possible action paths. That is why mobile robotics problems are complex with many unanswered questions. To reach a high degree of autonomous operation, a new level of learning is required. On the one hand, promising learning theories such as the adaptive critic and creative control have been proposed, while on other hand the human brain"s processing ability has amazed and inspired researchers in the area of Unmanned Ground Vehicles but has been difficult to emulate in practice. A new direction in the fuzzy theory tries to develop a theory to deal with the perceptions conveyed by the natural language. This paper tries to combine these two fields and present a framework for autonomous robot navigation. The proposed creative controller like the adaptive critic controller has information stored in a dynamic database (DB), plus a dynamic task control center (TCC) that functions as a command center to decompose tasks into sub-tasks with different dynamic models and multi-criteria functions. The TCC module utilizes computational theory of perceptions to deal with the high levels of task planning. The authors are currently trying to implement the model on a real mobile robot and the preliminary results have been described in this paper.

  14. Tug fleet and ground operations schedules and controls. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1975-01-01

    This study presents Tug Fleet and Ground Operations Schedules and Controls plan. This plan was developed and optimized out of a combination of individual Tug program phased subplans, special emphasis studies, contingency analyses and sensitivity analyses. The subplans cover the Tug program phases: (1) Tug operational, (2) Interim Upper Stage (IUS)/Tug fleet utilization, (3) and IUS/Tug payload integration, (4) Tug site activation, (5) IUS/Tug transition, (6) Tug acquisition. Resource requirements (facility, GSE, TSE, software, manpower, logistics) are provided in each subplan, as are appropriate Tug processing flows, active and total IUS and Tug fleet requirements, fleet management and Tug payload integration concepts, facility selection recommendations, site activation and IUS to Tug transition requirements. The impact of operational concepts on Tug acquisition is assessed and the impact of operating Tugs out of KSC and WTR is analyzed and presented showing WTR as a delta. Finally, cost estimates for fleet management and ground operations of the DDT&E and operational phases of the Tug program are given.

  15. Optimal control of the population dynamics of the ground vibrational state of a polyatomic molecule

    NASA Astrophysics Data System (ADS)

    de Clercq, Ludwig E.; Botha, Lourens R.; Rohwer, Erich G.; Uys, Hermann; Du Plessis, Anton

    2011-03-01

    Simulating coherent control with femtosecond pulses on a polyatomic molecule with anharmonic splitting was demonstrated. The simulation mimicked pulse shaping of a Spatial Light Modulator (SLM) and the interaction was described with the Von Neumann equation. A transform limited pulse with a fluence of 600 J/m2 produced 18% of the population in an arbitrarily chosen upper vibrational state, n =2. Phase only and amplitude only shaped pulse produced optimum values of 60% and 40% respectively, of the population in the vibrational state, n=2, after interaction with the ultra short pulse. The combination of phase and amplitude shaping produced the best results, 80% of the population was in the targeted vibrational state, n=2, after interaction. These simulations were carried out with all the population initially in the ground vibrational level. It was found that even at room temperatures (300 Kelvin) that the population in the selected level is comparable with the case where all population is initially in the ground vibrational state. With a 10% noise added to the amplitude and phase masks, selective excitation of the targeted vibrational state is still possible.

  16. The development of an UAV borne direct georeferenced photogrammetric platform for Ground Control Point free applications.

    PubMed

    Chiang, Kai-Wei; Tsai, Meng-Lun; Chu, Chien-Hsun

    2012-01-01

    To facilitate applications such as environment detection or disaster monitoring, the development of rapid low cost systems for collecting near real time spatial information is very critical. Rapid spatial information collection has become an emerging trend for remote sensing and mapping applications. In this study, a fixed-wing Unmanned Aerial Vehicle (UAV)-based spatial information acquisition platform that can operate in Ground Control Point (GCP) free environments is developed and evaluated. The proposed UAV based photogrammetric platform has a Direct Georeferencing (DG) module that includes a low cost Micro Electro Mechanical Systems (MEMS) Inertial Navigation System (INS)/Global Positioning System (GPS) integrated system. The DG module is able to provide GPS single frequency carrier phase measurements for differential processing to obtain sufficient positioning accuracy. All necessary calibration procedures are implemented. Ultimately, a flight test is performed to verify the positioning accuracy in DG mode without using GCPs. The preliminary results of positioning accuracy in DG mode illustrate that horizontal positioning accuracies in the x and y axes are around 5 m at 300 m flight height above the ground. The positioning accuracy of the z axis is below 10 m. Therefore, the proposed platform is relatively safe and inexpensive for collecting critical spatial information for urgent response such as disaster relief and assessment applications where GCPs are not available. PMID:23012538

  17. The Development of an UAV Borne Direct Georeferenced Photogrammetric Platform for Ground Control Point Free Applications

    PubMed Central

    Chiang, Kai-Wei; Tsai, Meng-Lun; Chu, Chien-Hsun

    2012-01-01

    To facilitate applications such as environment detection or disaster monitoring, the development of rapid low cost systems for collecting near real time spatial information is very critical. Rapid spatial information collection has become an emerging trend for remote sensing and mapping applications. In this study, a fixed-wing Unmanned Aerial Vehicle (UAV)-based spatial information acquisition platform that can operate in Ground Control Point (GCP) free environments is developed and evaluated. The proposed UAV based photogrammetric platform has a Direct Georeferencing (DG) module that includes a low cost Micro Electro Mechanical Systems (MEMS) Inertial Navigation System (INS)/Global Positioning System (GPS) integrated system. The DG module is able to provide GPS single frequency carrier phase measurements for differential processing to obtain sufficient positioning accuracy. All necessary calibration procedures are implemented. Ultimately, a flight test is performed to verify the positioning accuracy in DG mode without using GCPs. The preliminary results of positioning accuracy in DG mode illustrate that horizontal positioning accuracies in the x and y axes are around 5 m at 300 m flight height above the ground. The positioning accuracy of the z axis is below 10 m. Therefore, the proposed platform is relatively safe and inexpensive for collecting critical spatial information for urgent response such as disaster relief and assessment applications where GCPs are not available. PMID:23012538

  18. Interoperability of unattended ground sensors with an open architecture controller using SensorML

    NASA Astrophysics Data System (ADS)

    Chambers, Jon; Fairgrieve, Scott

    2010-04-01

    Unattended Ground Sensors (UGS) from a wide range of manufacturers have difficulty interoperating with each other and common control and dissemination points. Typically, sensor data is transmitted via RF or wired connections to a central location where the data can be fused together and transmitted further via satellite to a Processing, Exploitation and Dissemination (PED) system. These PED's are charged with analyzing the data to create real time actionable intelligence for the war fighter. However, when several disparate sensors from different manufacturers are used, interoperability problems arise. Therefore, a central UGS controller that accepts data from a wide range of sensors and helps them interoperate is essential. This paper addresses benefits derived from using the Open Geospatial Consortium's (OGC) Sensor Model Language (SensorML) sensor descriptions for an UGS controller. SensorML 1.0 is an approved OGC standard and is one of the major components within the OGC Sensor Web Enablement (SWE) suite of standards. SensorML provides standard models and an XML encoding for describing any process, including the process of measurement by sensors. By incorporating SensorML, an UGS controller can accept data from various sensors from different manufacturers, and interpret that data with the SensorML descriptions to allow the controller to take programmed actions and interoperate between sensors. Furthermore, SensorML can be used to translate the native sensor formats once the original data has been transmitted to the PED. Therefore, this makes a SensorML enabled UGS controller an extremely powerful tool that provides situational awareness by combining multiple sensors to form a single common operational picture (COP).

  19. A new approach for automatic matching of ground control points in urban areas from heterogeneous images

    NASA Astrophysics Data System (ADS)

    Cong, Chao; Liu, Dingsheng; Zhao, Lingjun

    2008-12-01

    This paper discusses a new method for the automatic matching of ground control points (GCPs) between satellite remote sensing Image and digital raster graphic (DRG) in urban areas. The key of this method is to automatically extract tie point pairs according to geographic characters from such heterogeneous images. Since there are big differences between such heterogeneous images respect to texture and corner features, more detail analyzations are performed to find similarities and differences between high resolution remote sensing Image and (DRG). Furthermore a new algorithms based on the fuzzy-c means (FCM) method is proposed to extract linear feature in remote sensing Image. Based on linear feature, crossings and corners extracted from these features are chosen as GCPs. On the other hand, similar method was used to find same features from DRGs. Finally, Hausdorff Distance was adopted to pick matching GCPs from above two GCP groups. Experiences shown the method can extract GCPs from such images with a reasonable RMS error.

  20. Controls on the distribution and isotopic composition of helium in deep ground-water flows

    USGS Publications Warehouse

    Zhao, X.; Fritzel, T.L.B.; Quinodoz, H.A.M.; Bethke, C.M.; Torgersen, T.

    1998-01-01

    The distribution and isotopic composition of helium in sedimentary basins can be used to interpret the ages of very old ground waters. The piston-flow model commonly used in such interpretation, how ever, does not account for several important factors and as such works well only in very simple flow regimes. In this study of helium transport in a hypothetical sedimentary basin, we develop a numerical model that accounts for the magnitude and distribution of the basal helium flux, hydrodynamic dispersion, and complexities in flow regimes such as subregional flow cells. The modeling shows that these factors exert strong controls on the helium distribution and isotopic composition. The simulations may provide a basis for more accurate interpretations of observed helium concentrations and isotopic ratios in sedimentary basins.

  1. A ground based phase control system for the solar power satellite. Executive summary, volume 1, phase 3

    NASA Technical Reports Server (NTRS)

    Chie, C. M.

    1980-01-01

    The Solar Power Satellite (SPS) concept and the reference phase control system investigated in earlier efforts are reviewed. A summary overview of the analysis and selection of the pilot signal and power transponder design is presented along with the SOLARSIM program development and the simulated SPS phase control performance. Evaluations of the ground based phase control system as an alternate phase control concept are summarized.

  2. Monitoring controlled graves representing common burial scenarios with ground penetrating radar

    NASA Astrophysics Data System (ADS)

    Schultz, John J.; Martin, Michael M.

    2012-08-01

    Implementing controlled geophysical research is imperative to understand the variables affecting detection of clandestine graves during real-life forensic searches. This study focused on monitoring two empty control graves (shallow and deep) and six burials containing a small pig carcass (Sus scrofa) representing different burial forensic scenarios: a shallow buried naked carcass, a deep buried naked carcass, a deep buried carcass covered by a layer of rocks, a deep buried carcass covered by a layer of lime, a deep buried carcass wrapped in an impermeable tarpaulin and a deep buried carcass wrapped in a cotton blanket. Multi-frequency, ground penetrating radar (GPR) data were collected monthly over a 12-month monitoring period. The research site was a cleared field within a wooded area in a humid subtropical environment, and the soil consisted of a Spodosol, a common soil type in Florida. This study compared 2D GPR reflection profiles and horizontal time slices obtained with both 250 and 500 MHz dominant frequency antennae to determine the utility of both antennae for grave detection in this environment over time. Overall, a combination of both antennae frequencies provided optimal detection of the targets. Better images were noted for deep graves, compared to shallow graves. The 250 MHz antenna provided better images for detecting deep graves, as less non-target anomalies were produced with lower radar frequencies. The 250 MHz antenna also provided better images detecting the disturbed ground. Conversely, the 500 MHz antenna provided better images when detecting the shallow pig grave. The graves that contained a pig carcass with associated grave items provided the best results, particularly the carcass covered with rocks and the carcass wrapped in a tarpaulin. Finally, during periods of increased soil moisture levels, there was increased detection of graves that was most likely related to conductive decompositional fluid from the carcasses.

  3. Sfm_georef: Automating image measurement of ground control points for SfM-based projects

    NASA Astrophysics Data System (ADS)

    James, Mike R.

    2016-04-01

    Deriving accurate DEM and orthomosaic image products from UAV surveys generally involves the use of multiple ground control points (GCPs). Here, we demonstrate the automated collection of GCP image measurements for SfM-MVS processed projects, using sfm_georef software (James & Robson, 2012; http://www.lancaster.ac.uk/staff/jamesm/software/sfm_georef.htm). Sfm_georef was originally written to provide geo-referencing procedures for SfM-MVS projects. It has now been upgraded with a 3-D patch-based matching routine suitable for automating GCP image measurement in both aerial and ground-based (oblique) projects, with the aim of reducing the time required for accurate geo-referencing. Sfm_georef is compatible with a range of SfM-MVS software and imports the relevant files that describe the image network, including camera models and tie points. 3-D survey measurements of ground control are then provided, either for natural features or artificial targets distributed over the project area. Automated GCP image measurement is manually initiated through identifying a GCP position in an image by mouse click; the GCP is then represented by a square planar patch in 3-D, textured from the image and oriented parallel to the local topographic surface (as defined by the 3-D positions of nearby tie points). Other images are then automatically examined by projecting the patch into the images (to account for differences in viewing geometry) and carrying out a sub-pixel normalised cross-correlation search in the local area. With two or more observations of a GCP, its 3-D co-ordinates are then derived by ray intersection. With the 3-D positions of three or more GCPs identified, an initial geo-referencing transform can be derived to relate the SfM-MVS co-ordinate system to that of the GCPs. Then, if GCPs are symmetric and identical, image texture from one representative GCP can be used to search automatically for all others throughout the image set. Finally, the GCP observations can be

  4. Application of radio control cars as intelligent unmanned ground vehicles with collaborative and independent behavior

    NASA Astrophysics Data System (ADS)

    Wasson, Steven R.; Kouns, John; Bruder, Stephen; Wedeward, Kevin; El-Osery, Aly

    2004-09-01

    Simple radio control cars commonly sold as toys can provide a viable starting platform for the development of low-cost intelligent Unmanned Ground Vehicles (UGVs) for the study of robot collectives. In a collaborative effort, Sandia National Labs and New Mexico Tech have successfully demonstrated proof-of-concept by utilizing low-cost radio control cars manufactured by Nikko. Initial tests have involved using a small number (two to ten) of these UGVs to successfully demonstrate both collaborative and independent behavior simultaneously. In the tests individuals share their locations with the collective to cover an area, thus demonstrating collaborative behavior. Independent behavior is demonstrated as each member of the collective maintains a desired compass heading while simultaneously avoiding obstacles in its path. These UGVs are powered by high-capacity rechargeable batteries and equipped with a custom-designed microcontroller board with a stackable modular interface and wireless communication. The initial modular sensor configuration includes a digital compass and GPS unit for navigation as well as ultrasonic sensors for obstacle avoidance. This paper describes the design and operations of these UGVs, their possible uses, and the advantages of using a radio control car platform as a low-cost starting point for the development of intelligent UGV collectives.

  5. Reactive Iron deposition and ground water inflow control neutralization processes in acidic mine lakes

    NASA Astrophysics Data System (ADS)

    Blodau, C.

    2002-12-01

    The controls on the internal neutralization of highly acidified waters by iron sulphide accumulation are yet poorly understood. To elucidate the influence of ground water inflow on neutralization processes, inventories of solid phase iron and sulphur, pore water profiles and rates of ferrous iron and sulphate production and consumption were analyzed in different areas of an acidic mine lake. Ground water inflow had previously been determined by ground water modelling and chamber measurements (Knoll et al., 1999). The investigated sediments adjacent to mine tailings, which were subject to the inflow of groundwater (10-30 L d-1 m-2), were richer in dissolved ferrous iron iron (30 vs. 5 mmol L-1) and sulphate (30 vs. 10 mmol L-1) and showed higher pH values (6 vs. 4) than the sediments in areas of the lake not being influenced by groundwater inflow. Sediments adjacent to the mine tailings also showed higher rates of sulphate reduction and iron sulphide accumulation (Fig. 1). From these data it is suggested that neutralization processes in iron rich, acidic mine lakes neutralization processes primarily occur in areas influenced by the inflow of acid mine groundwater. These waters usually have considerably higher pH values than the surface waters in the lakes due to buffering processes in the tailings. The seepage of this water through the sediment might thus lead to higher pH values and thus to a higher thermodynamic competitiveness of sulfate reduction vs. iron reduction (Blodau and Peiffer 2002). This causes increased neutralization rates. These findings have consequences for remediation measures in highly acidic lakes. In areas influenced by the inflow of mine drainage increases in carbon availability, for example by the deposition of particulate organic matter, should enhance iron sulphide formation rates, whereas in other areas increases in carbon availability would only result in enhanced rates of iron reduction without a lasting gain in alkalinity. Blodau, C

  6. Controlling laser beam irradiation area using an optical duplicate system to improve satellite–ground laser communications

    NASA Astrophysics Data System (ADS)

    Nakayama, Tomoko; Takayama, Yoshihisa; Fujikawa, Chiemi; Kodate, Kashiko

    2016-08-01

    To improve the quality of ground to satellite laser communications, we propose an optical duplicate system of the optical ground station. Our proposed approach can be used to control the beam irradiation area for a satellite position without changing the total power of the output beam and the mechanical drive unit; this is performed by controlling the input pattern of a liquid crystal filter inserted in the input plane of the optical duplicate system. Most of the power of the diffracted laser beam emitted from the ground is focused on the optical axis. By distributing the power to side lobes, it is possible to extend the coverage area for a satellite position. This system allows the laser beam irradiation area to be controlled by a sufficient degree by adjusting the threshold of the satellite reception level. We verify the efficacy of the system using wave optics numerical calculations.

  7. A new method to obtain uniform distribution of ground control points based on regional statistical information

    NASA Astrophysics Data System (ADS)

    Ma, Chao; An, Wei; Deng, Xinpu

    2015-10-01

    The Ground Control Points (GCPs) is an important source of fundamental data in geometric correction for remote sensing imagery. The quantity, accuracy and distribution of GCPs are three factors which may affect the accuracy of geometric correction. It is generally required that the distribution of GCP should be uniform, so they can fully control the accuracy of mapping regions. In this paper, we establish an objective standard of evaluating the uniformity of the GCPs' distribution based on regional statistical information (RSI), and get an optimal distribution of GCPs. This sampling method is called RSIS for short in this work. The Amounts of GCPs in different regions by equally partitioning the image in regions in different manners are counted which forms a vector called RSI vector in this work. The uniformity of GCPs' distribution can be evaluated by a mathematical quantity of the RSI vector. An optimal distribution of GCPs is obtained by searching the RSI vector with the minimum mathematical quantity. In this paper, the simulation annealing is employed to search the optimal distribution of GCPs that have the minimum mathematical quantity of the RSI vector. Experiments are carried out to test the method proposed in this paper, and sampling designs compared are simple random sampling and universal kriging model-based sampling. The experiments indicate that this method is highly recommended as new GCPs sampling design method for geometric correction of remotely sensed imagery.

  8. Ground Laboratory Soft X-Ray Durability Evaluation of Aluminized Teflon FEP Thermal Control Insulation. Revised

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A.; deGroh, Kim K.; Stueber, Thomas J.; Sechkar, Edward A.; Hall, Rachelle L.

    1998-01-01

    Metallized Teflon fluorinated ethylene propylene (FEP) thermal control insulation is mechanically degraded if exposed to a sufficient fluence of soft x-ray radiation. Soft x-ray photons (4-8 A in wavelength or 1.55 - 3.2 keV) emitted during solar flares have been proposed as a cause of mechanical properties degradation of aluminized Teflon FEP thermal control insulation on the Hubble Space Telescope (HST). Such degradation can be characterized by a reduction in elongation-to-failure of the Teflon FEP. Ground laboratory soft x-ray exposure tests of aluminized Teflon FEP were conducted to assess the degree of elongation degradation which would occur as a result of exposure to soft x-rays in the range of 3-10 keV. Tests results indicate that soft x-ray exposure in the 3-10 keV range, at mission fluence levels, does not alone cause the observed reduction in elongation of flight retrieved samples. The soft x-ray exposure facility design, mechanical properties degradation results and implications will be presented.

  9. Ground Laboratory Soft X-Ray Durability Evaluation of Aluminized Teflon FEP Thermal Control Insulation

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A.; deGroh, Kim K.; Stueber, Thomas J.; Sechkar, Edward A.

    1998-01-01

    Metallized Teflon fluorinated ethylene propylene (FEP) thermal control insulation is mechanically degraded if exposed to a sufficient fluence of soft x-ray radiation. Soft x-ray photons (4-8 A in wavelength or 1.55 - 3.2 keV) emitted during solar flares have been proposed as a cause of mechanical properties degradation of aluminized Teflon FEP thermal control insulation on the Hubble Space Telescope (HST). Such degradation can be characterized by a reduction in elongation-to-failure of the Teflon FER Ground laboratory soft x-ray exposure tests of aluminized Teflon FEP were conducted to assess the degree of elongation degradation which would occur as a result of exposure to soft x-rays in the range of 3-10 keV. Tests results indicate that soft x-ray exposure in the 3-10 keV range, at mission fluence levels, does not alone cause the observed reduction in elongation of flight retrieved samples. The soft x-ray exposure facility design, mechanical properties degradation results and implications will be presented.

  10. Ground Simulator Studies of the Effects of Valve Friction, Stick Friction, Flexibility, and Backwash on Power Control System Quality

    NASA Technical Reports Server (NTRS)

    Brown, B Porter

    1958-01-01

    Report presents results of tests made on a power control system by means of a ground simulator to determine the effects of various combinations of valve friction and stick friction on the ability of the pilot to control the system. Various friction conditions were simulated with a rigid control system, a flexible system, and a rigid system having some backlash. For the tests, the period and damping of the simulated airplane were held constant.

  11. Technologies for low-bandwidth high-latency unmanned ground vehicle control

    NASA Astrophysics Data System (ADS)

    Pace, Teresa; Cogan, Ken; Hunt, Lee; Restine, Paul

    2014-05-01

    Automation technology has evolved at a rapid pace in recent years; however, many real-world problems require contextual understanding, problem solving, and other forms of higher-order thinking that extends beyond the capabilities of robots for the foreseeable future. This limits the complexity of automation which can be supplied to modern unmanned ground robots (UGV) and necessitates human-in-the-loop monitoring and control for some portions of missions. In order for the human operator to make decisions and provide tasking during key portions of the mission, existing solutions first derive significant information from a potentially dense reconstruction of the scene utilizing LIDAR, video, and other onboard sensors. A dense reconstruction contains too much data for real-time transmission over a modern wireless data link, so the robot electronics must first condense the scene representation prior to transmission. The control station receives this condensed scene representations and provides visual information to the human operator; the human operator then provides tele-operation commands in real-time to the robot. This paper discusses approaches to dense scene reduction of the data required to transmit to a human-in-the loop as well as the challenges associated with them. In addition, the complex and unstructured nature of real-world environments increases the need for tele-operation. Furthermore, many environments reduce the bandwidth and increase the latency of the link. Ultimately, worsening conditions will cause the tele-operation control process to break down, rendering the robot ineffective. In a worst-case scenario, extreme conditions causing a complete loss-of-communications could result in mission failure and loss of the vehicle.

  12. Integrated Vehicle Ground Vibration Testing in Support of NASA Launch Vehicle Loads and Controls Analysis

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret L.; Davis, Susan R.; Askins, Bruce R.; Salyer, Blaine H.

    2008-01-01

    The National Aeronautics and Space Administration (NASA) Ares Projects Office (APO) is continuing to make progress toward the final design of the Ares I crew launch vehicle and Ares V cargo launch vehicle. Ares I and V will form the space launch capabilities necessary to fulfill NASA's exploration strategy of sending human beings to the Moon, Mars, and beyond. As with all new space vehicles there will be a number of tests to ensure the design can be Human Rated. One of these is the Integrated Vehicle Ground Vibration Test (IVGVT) that will be measuring responses of the Ares I as a system. All structural systems possess a basic set of physical characteristics unique to that system. These unique characteristics include items such as mass distribution, frequency and damping. When specified, they allow engineers to understand and predict how a structural system like the Ares I launch vehicle behaves under given loading conditions. These physical properties of launch vehicles may be predicted by analysis or measured through certain types of tests. Generally, these properties are predicted by analysis during the design phase of a launch vehicle and then verified through testing before the vehicle is Human Rated. The IVGVT is intended to measure by test the fundamental dynamic characteristics of Ares I during various phases of operational/flight. This testing includes excitations of the vehicle in lateral, longitudinal, and torsional directions at vehicle configurations representing different trajectory points. During the series of tests, properties such as natural frequencies, mode shapes, and transfer functions are measured directly. These data will then be used to calibrate loads and Guidance, Navigation, and Controls (GN&C) analysis models for verifying analyses of Ares I. NASA launch vehicles from Saturn to Shuttle have undergone Ground Vibration Tests (GVTs) leading to successful launch vehicles. A GVT was not performed on the unmanned Delta III. This vehicle was

  13. Image processing and computer controls for video profile diagnostic system in the ground test accelerator (GTA)

    SciTech Connect

    Wright, R.M.; Zander, M.E.; Brown, S.K.; Sandoval, D.P.; Gilpatrick, J.D.; Gibson, H.E.

    1992-09-01

    This paper describes the application of video image processing to beam profile measurements on the Ground Test Accelerator (GTA). A diagnostic was needed to measure beam profiles in the intermediate matching section (IMS) between the radio-frequency quadrupole (RFQ) and the drift tube linac (DTL). Beam profiles are measured by injecting puffs of gas into the beam. The light emitted from the beam-gas interaction is captured and processed by a video image processing system, generating the beam profile data. A general purpose, modular and flexible video image processing system, imagetool, was used for the GTA image profile measurement. The development of both software and hardware for imagetool and its integration with the GTA control system (GTACS) will be discussed. The software includes specialized algorithms for analyzing data and calibrating the system. The underlying design philosophy of imagetool was tested by the experience of building and using the system, pointing the way for future improvements. The current status of the system will be illustrated by samples of experimental data.

  14. Image processing and computer controls for video profile diagnostic system in the ground test accelerator (GTA)

    SciTech Connect

    Wright, R.M.; Zander, M.E.; Brown, S.K.; Sandoval, D.P.; Gilpatrick, J.D.; Gibson, H.E.

    1992-01-01

    This paper describes the application of video image processing to beam profile measurements on the Ground Test Accelerator (GTA). A diagnostic was needed to measure beam profiles in the intermediate matching section (IMS) between the radio-frequency quadrupole (RFQ) and the drift tube linac (DTL). Beam profiles are measured by injecting puffs of gas into the beam. The light emitted from the beam-gas interaction is captured and processed by a video image processing system, generating the beam profile data. A general purpose, modular and flexible video image processing system, imagetool, was used for the GTA image profile measurement. The development of both software and hardware for imagetool and its integration with the GTA control system (GTACS) will be discussed. The software includes specialized algorithms for analyzing data and calibrating the system. The underlying design philosophy of imagetool was tested by the experience of building and using the system, pointing the way for future improvements. The current status of the system will be illustrated by samples of experimental data.

  15. Kennedy Space Center Timing and Countdown Interface to Kennedy Ground Control Subsystem

    NASA Technical Reports Server (NTRS)

    Olsen, James C.

    2015-01-01

    Kennedy Ground Control System (KGCS) engineers at the National Aeronautics and Space Administration (NASA) Kennedy Space Center (KSC) are developing a time-tagging process to enable reconstruction of the events during a launch countdown. Such a process can be useful in the case of anomalies or other situations where it is necessary to know the exact time an event occurred. It is thus critical for the timing information to be accurate. KGCS will synchronize all items with Coordinated Universal Time (UTC) obtained from the Timing and Countdown (T&CD) organization. Network Time Protocol (NTP) is the protocol currently in place for synchronizing UTC. However, NTP has a peak error that is too high for today's standards. Precision Time Protocol (PTP) is a newer protocol with a much smaller peak error. The focus of this project has been to implement a PTP solution on the network to increase timing accuracy while introducing and configuring the implementation of a firewall between T&CD and the KGCS network.

  16. Inactivation of foodborne pathogens in ground beef by cooking with highly controlled radio frequency energy.

    PubMed

    Schlisselberg, Dov B; Kler, Edna; Kalily, Emmanuel; Kisluk, Guy; Karniel, Ohad; Yaron, Sima

    2013-01-01

    The consumer demand for fresh tasting, high quality, low salt, preservative-free meals which require minimal preparation time magnifies the safety concern and emphasizes the need to use innovative technologies for food processing. A modern technique to uniformly heat and cook foods is based on a combination of convection and controlled radio frequency (RF) energy. However any advantage conferred on meat cooked by this method would be lost if application of the technology results in decreased safety. Our main goal was to study the inactivation efficacy of this method of cooking against pathogens in ground meat in comparison to standard convection cooking. Meat balls were artificially inoculated with GFP expressing Escherichia coli, Salmonella Typhimurium and Listeria monocytogenes as well as spores of Bacillus cereus and Bacillus thuringiensis and cooked by convection heating (220°C, 40 min), by using energy generated from frequencies in the RF bandwidth (RF cooking, 7.5 min) or by combined heating (5.5 min), until the center temperature of each sample reached 73°C. The mean reductions in total indigenous bacteria obtained by RF and convection were 2.8 and 2.5 log CFU/g, respectively. Cooking of meat balls with convection reduced the E. coli population (8 log CFU/g) by 5.5 log CFU/g, whilst treatment with RF reduced E. coli population to undetectable levels. The mean reductions of S. Typhimurium obtained by RF and convection were 5.7 and 6.5 log CFU/g, respectively. The combined treatment reduced the Salmonella population to undetectable levels. In contrast, L. monocytogenes was poorly affected by RF cooking. The mean reduction of L. monocytogenes obtained by RF energy was 0.4 log CFU/g, while convection cooking resulted in undetectable levels. Interestingly, the combined treatment also resulted with undetectable levels of Listeria although time of cooking was reduced by 86%. One-step cooking had negligible effects on the Bacillus spores and therefore a 2-step

  17. The Design of Ground Operation Control System Based on Red5 & Flex

    NASA Astrophysics Data System (ADS)

    Guilin, Zhou; Chunlin, Li; Houyi

    According to the ground production of Beijing branch of China Southern Airlines, a production monitoring ground system was designed. The system is mainly used for ground monitoring of aircraft loading and production activities at the airfield, and use the event mechanism to coordinate the production work of SOC, CGS, cargo and aircraft maintenance factory. The system will provide strong support for SOC's work and has great significance for the protection of normal flights and investigation of delays. This innovative design proposed the online games conception and architecture to deal the production problems, and satisfy the front-line operational unit's strong demand of real-time, ease use and ease deployment.

  18. Design opimization in underground coal systems. Volume X. Underground longwall ground control simulator (LONGWALGRCON-SIM). Final technical report

    SciTech Connect

    Not Available

    1981-02-28

    A detailed literature review was conducted with particular reference to the ground-control mechanisms of longwall mining systems in the United States. In addition a longwall simulator program was constructed to facilitate equipment selection and design on the longwall face and the support requirements that might be needed in the head and tail entries. The mechanics of ground behavior around the longwall face and the head and tail entries were analyzed and formed the basis for the computer program. The computer simulator LONGWALGRCON-SIM to represent face behavior and specify face equipment capacities was completed. Roof classification for the head and tail entries can be included in the simulator output if optioned. A user manual for the program was produced, including typical program input and output together with the logic used in the program. The major application of the research lies in the application of the computer program to facilitiate design of new longwall operations. Significant conclusions are as follows: insufficient information exists for US longwall mining operations to derive totally reliable ground-control relationships; the longwall simulator does establish the practicality of computer-assisted design of longwall operations; the data requirements of LONGWALGRCON-SIM provide a framework for the collection of ground-control data necessary for face-and-entry design; and face-support requirements can be specified using the computer-assisted, longwall-face simulator.

  19. FROZEN GROUND CONTROL ON SNOWMELT FLOWPATHS AND SURFACE WATER CHEMISTRY IN TWO ALPINE BASINS

    EPA Science Inventory

    This study will increase our understanding of how snowmelt flowpaths are influenced by frozen ground in mid-latitude alpine basins. It also will elucidate how these flowpaths dictate surface water chemistry in relation to snowmelt.

  20. Remote-Controlled Electrical Resistivity Tomography and Concurrent Ground-Penetrating Radar Laboratory

    NASA Astrophysics Data System (ADS)

    Kruger, A.; Daniels, J. J.; Yeh, T. J.; Zhu, J.; Niemeier, J. J.; Mansheim, T. J.; Hart, T. R.; Shaelek, K. S.; Illman, W. A.; Craig, A. J.

    2008-12-01

    A team of researchers at The University of Iowa, Ohio State University, and the University of Arizona have developed an over-the-internet experimental setup that enables researchers and educators at remote locations to make concurrent electrical resistivity tomography (ERT) and ground penetrating radar (GPR) measurements. The setup is comprised of a carefully constructed sandbox with known layers of sand with embedded wells and ERT electrodes. A GPR transmitter and receiver are mounted on an xy-traverse scanner. Computers control all the components. Computer software and communications interfaces allow remote users to perform concurrent ERT and GPR measurements and retrieve the measured results in real- time over the internet. A camera enables each internet user to view the active experiment. The users can then apply various inversion- and post-processing algorithms to the data, fuse their results, interpret the data, and adjust the data collection for additional data runs. The system allows for flexible and rapid ERT measurements by researchers developing inversion algorithms, and near real-time 3D images of dielectric constant variations (moisture and water concentrations) in the model. It also has utility in geophysics education, enabling real-time demonstration of ERT and GPR measurements. The distributed arrangement allows institutions at different locations to collaborate and leverage their individual strengths: experimental and cyberinfrastructure knowledge, ERT expertise, and GPR expertise. Large subsystems in the laboratory were designed as stand-alone equipment without any network capability, and this posed major technical obstacles. Our plans include extending the system to interface with pumps and pressure transducers to facilitate hydrologic tomography experiments and possibly offer the research setup to other investigators who do not have access to a laboratory system.

  1. Instrument Display Visual Angles for Conventional Aircraft and the MQ-9 Ground Control Station

    NASA Technical Reports Server (NTRS)

    Bendrick, Gregg A.; Kamine, Tovy Haber

    2008-01-01

    Aircraft instrument panels should be designed such that primary displays are in optimal viewing location to minimize pilot perception and response time. Human Factors engineers define three zones (i.e. "cones") of visual location: 1) "Easy Eye Movement" (foveal vision); 2) "Maximum Eye Movement" (peripheral vision with saccades), and 3) "Head Movement" (head movement required). Instrument display visual angles were measured to determine how well conventional aircraft (T-34, T-38, F- 15B, F-16XL, F/A-18A, U-2D, ER-2, King Air, G-III, B-52H, DC-10, B747-SCA) and the MQ-9 ground control station (GCS) complied with these standards, and how they compared with each other. Methods: Selected instrument parameters included: attitude, pitch, bank, power, airspeed, altitude, vertical speed, heading, turn rate, slip/skid, AOA, flight path, latitude, longitude, course, bearing, range and time. Vertical and horizontal visual angles for each component were measured from the pilot s eye position in each system. Results: The vertical visual angles of displays in conventional aircraft lay within the cone of "Easy Eye Movement" for all but three of the parameters measured, and almost all of the horizontal visual angles fell within this range. All conventional vertical and horizontal visual angles lay within the cone of "Maximum Eye Movement". However, most instrument vertical visual angles of the MQ-9 GCS lay outside the cone of "Easy Eye Movement", though all were within the cone of "Maximum Eye Movement". All the horizontal visual angles for the MQ-9 GCS were within the cone of "Easy Eye Movement". Discussion: Most instrument displays in conventional aircraft lay within the cone of "Easy Eye Movement", though mission-critical instruments sometimes displaced less important instruments outside this area. Many of the MQ-9 GCS systems lay outside this area. Specific training for MQ-9 pilots may be needed to avoid increased response time and potential error during flight.

  2. Tools for automating spacecraft ground systems: The Intelligent Command and Control (ICC) approach

    NASA Technical Reports Server (NTRS)

    Stoffel, A. William; Mclean, David

    1996-01-01

    The practical application of scripting languages and World Wide Web tools to the support of spacecraft ground system automation, is reported on. The mission activities and the automation tools used at the Goddard Space Flight Center (MD) are reviewed. The use of the Tool Command Language (TCL) and the Practical Extraction and Report Language (PERL) scripting tools for automating mission operations is discussed together with the application of different tools for the Compton Gamma Ray Observatory ground system.

  3. The cost of developing and maintain the monitoring and control software of large ground-based telescopes

    NASA Astrophysics Data System (ADS)

    Guzman, Juan Carlos; Chiozzi, Gianluca; Bridger, Alan; Ibsen, Jorge

    2014-07-01

    There are several large ground-based telescopes currently under development such as the SKA and CCAT in radio as well as several 30m-class in the optical. A common challenge that all of these telescopes are facing is estimating the cost of design, construction and maintenance of their required software. This paper will present a cost breakdown of the monitoring and control software packages implemented for ASKAP including the effort spent to develop and maintain the in-house code and the effort saved by using third-party software, such as EPICS. The costing for ASKAP will be compared to those for the monitoring and control software of other large ground-based telescopes such as ALMA and VLT. This comparison will highlight trends and commonalities in the costing and provides a useful guide for costing future telescope control software builds or upgrades and the ongoing maintenance cost.

  4. Intelligent tutoring and aiding in satellite ground control. Ph.D. Thesis - Georgia Inst. of Tech., 1991

    NASA Technical Reports Server (NTRS)

    Chu, Rose W.; Mitchell, Christine M.

    1993-01-01

    In supervisory control systems such as satellite ground control, there is a need for human-centered automation where the focus is to understand and enhance the human-system interaction experience in the complex task environment. Operator support in the form of off-line intelligent tutoring and on-line intelligent aiding is one approach towards this effort. The tutor/aid paradigm is proposed here as a design approach that integrates the two aspects of operator support in one system for technically oriented adults in complex domains. This paper also presents GT-VITA, a proof-of-concept graphical, interactive, intelligent tutoring system that is a first attempt to illustrate the tutoring aspect of the tutor/aid paradigm in the domain of satellite ground control. Evaluation on GT-VITA is conducted with NASA personnel with very positive results. GT-VITA is presented being fielded as it is at Goddard Space Flight Center.

  5. Integrated optimal dynamics control of 4WD4WS electric ground vehicle with tire-road frictional coefficient estimation

    NASA Astrophysics Data System (ADS)

    Wang, Rongrong; Hu, Chuan; Wang, Zejiang; Yan, Fengjun; Chen, Nan

    2015-08-01

    This paper presents an integrated optimal dynamics control of four-wheel driving and four-wheel steering (4WD4WS) electric ground vehicles via hierarchical control methodology. In the higher-level design, an LQR controller is proposed to obtain the integrated lateral force and yaw moment, according to their respective reference values. The lower-level controller is designed to ensure all the tires work in the stable region while realizing the tracking control of the vehicle dynamics. The tire-road friction coefficient is estimated through the integrated longitudinal force and lateral force, respectively, using a brush tire model. To reduce the estimation error, a novel data fusion function is employed to generate the final estimation value. Finally, the effectiveness of the proposed control and estimation strategies is validated via CarSim-Simulink joint simulation.

  6. Microtopographic and depth controls on active layer chemistry in Arctic polygonal ground

    SciTech Connect

    Newman, Brent D.; Throckmorton, Heather M.; Graham, David E.; Gu, Baohua; Hubbard, Susan S.; Liang, Liyuan; Wu, Yuxin; Heikoop, J. M.; Herndon, Elizabeth M.; Phelps, Tommy J.; Wilson, Cathy; Wullschleger, Stan D.

    2015-03-24

    Polygonal ground is a signature characteristic of Arctic lowlands, and carbon release from permafrost thaw can alter feedbacks to Arctic ecosystems and climate. This study describes the first comprehensive spatial examination of active layer biogeochemistry that extends across high- and low-centered, ice wedge polygons, their features, and with depth. Water chemistry measurements of 54 analytes were made on surface and active layer pore waters collected near Barrow, Alaska, USA. Significant differences were observed between high- and low-centered polygons suggesting that polygon types may be useful for landscape-scale geochemical classification. However, differences were found for polygon features (centers and troughs) for analytes that were not significant for polygon type, suggesting that finer-scale features affect biogeochemistry differently from polygon types. Depth variations were also significant, demonstrating important multidimensional aspects of polygonal ground biogeochemistry. These results have major implications for understanding how polygonal ground ecosystems function, and how they may respond to future change.

  7. Microtopographic and depth controls on active layer chemistry in Arctic polygonal ground

    NASA Astrophysics Data System (ADS)

    Newman, B. D.; Throckmorton, H. M.; Graham, D. E.; Gu, B.; Hubbard, S. S.; Liang, L.; Wu, Y.; Heikoop, J. M.; Herndon, E. M.; Phelps, T. J.; Wilson, C. J.; Wullschleger, S. D.

    2015-03-01

    Polygonal ground is a signature characteristic of Arctic lowlands, and carbon release from permafrost thaw can alter feedbacks to Arctic ecosystems and climate. This study describes the first comprehensive spatial examination of active layer biogeochemistry that extends across high- and low-centered, ice wedge polygons, their features, and with depth. Water chemistry measurements of 54 analytes were made on surface and active layer pore waters collected near Barrow, Alaska, USA. Significant differences were observed between high- and low-centered polygons suggesting that polygon types may be useful for landscape-scale geochemical classification. However, differences were found for polygon features (centers and troughs) for analytes that were not significant for polygon type, suggesting that finer-scale features affect biogeochemistry differently from polygon types. Depth variations were also significant, demonstrating important multidimensional aspects of polygonal ground biogeochemistry. These results have major implications for understanding how polygonal ground ecosystems function, and how they may respond to future change.

  8. Instrument Display Visual Angles for Conventional Aircraft and the MQ-9 Ground Control Station

    NASA Technical Reports Server (NTRS)

    Kamine, Tovy Haber; Bendrick, Gregg A.

    2008-01-01

    Aircraft instrument panels should be designed such that primary displays are in optimal viewing location to minimize pilot perception and response time. Human Factors engineers define three zones (i.e. cones ) of visual location: 1) "Easy Eye Movement" (foveal vision); 2) "Maximum Eye Movement" (peripheral vision with saccades), and 3) "Head Movement (head movement required). Instrument display visual angles were measured to determine how well conventional aircraft (T-34, T-38, F- 15B, F-16XL, F/A-18A, U-2D, ER-2, King Air, G-III, B-52H, DC-10, B747-SCA) and the MQ-9 ground control station (GCS) complied with these standards, and how they compared with each other. Selected instrument parameters included: attitude, pitch, bank, power, airspeed, altitude, vertical speed, heading, turn rate, slip/skid, AOA, flight path, latitude, longitude, course, bearing, range and time. Vertical and horizontal visual angles for each component were measured from the pilot s eye position in each system. The vertical visual angles of displays in conventional aircraft lay within the cone of "Easy Eye Movement" for all but three of the parameters measured, and almost all of the horizontal visual angles fell within this range. All conventional vertical and horizontal visual angles lay within the cone of Maximum Eye Movement. However, most instrument vertical visual angles of the MQ-9 GCS lay outside the cone of Easy Eye Movement, though all were within the cone of Maximum Eye Movement. All the horizontal visual angles for the MQ-9 GCS were within the cone of "Easy Eye Movement". Most instrument displays in conventional aircraft lay within the cone of Easy Eye Movement, though mission-critical instruments sometimes displaced less important instruments outside this area. Many of the MQ-9 GCS systems lay outside this area. Specific training for MQ-9 pilots may be needed to avoid increased response time and potential error during flight. The learning objectives include: 1) Know three

  9. Ground-based technologies for cotton root rot control: Results from a three-year experiment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The overall goal of this research is to develop ground-based technologies for disease detection and mapping which can maximize the effectiveness and efficiency of CRR (cotton root rot) treatments. Accurately mapping CRR could facilitate a much more economical solution than treating entire fields. Th...

  10. NUTRIENT, BACTERIAL, AND VIRUS CONTROL AS RELATED TO GROUND-WATER CONTAMINATION

    EPA Science Inventory

    A general introduction provides something of the history of groundwater, its present use, and the means by which it can become contaminated. A priority listing of sources of ground-water contamination is presented for four geographical areas of the United States. Phosphorus is di...

  11. Ground-based technologies for cotton root rot control: an update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The overall goal of this research is to develop ground-based technologies for early detection and site-specific management of CRR (cotton root rot). Early detection could facilitate a more economical solution than those that might be used after plant infection had become more severe and widespread. ...

  12. Migration of Contaminated Ground Water Under Control at High-Priority Cleanup Sites

    EPA Science Inventory

    This indicator describes the percentage of National Priority List (NPL) or Superfund Indicator Baseline sites and Resource Conservation and Recovery Act (RCRA) Cleanup Baseline sites from 2000 to 2007 where government officials have determined that contaminated ground water is...

  13. The SAX Italian scientific satellite. The on-board implemented automation as a support to the ground control capability

    NASA Technical Reports Server (NTRS)

    Martelli, Andrea

    1994-01-01

    This paper presents the capabilities implemented in the SAX system for an efficient operations management during its in-flight mission. SAX is an Italian scientific satellite for x-ray astronomy whose major mission objectives impose quite tight constraints on the implementation of both the space and ground segment. The most relevant mission characteristics require an operative lifetime of two years, performing scientific observations both in contact and in noncontact periods, with a low equatorial orbit supported by one ground station, so that only a few minutes of communications are available each orbit. This operational scenario determines the need to have a satellite capable of performing the scheduled mission automatically and reacting autonomously to contingency situations. The implementation approach of the on-board operations management, through which the necessary automation and autonomy are achieved, follows a hierarchical structure. This has been achieved adopting a distributed avionic architecture. Nine different on-board computers, in fact, constitute the on-board data management system. Each of them performs the local control and monitors its own functions while the system level control is performed at a higher level by the data handling applications software. The SAX on-board architecture provides the ground operators with different options of intervention by three classes of telecommands. The management of the scientific operations will be scheduled by the operation control center via dedicated operating plans. The SAX satellite flight mode is presently being integrated at Alenia Spazio premises in Turin for a launch scheduled for the end of 1995. Once in orbit, the SAX satellite will be subject to intensive check-out activities in order to verify the required mission performances. An overview of the envisaged procedure and of the necessary on-ground activities is therefore depicted as well.

  14. Controlling stress corrosion cracking in mechanism components of ground support equipment

    NASA Technical Reports Server (NTRS)

    Majid, W. A.

    1988-01-01

    The selection of materials for mechanism components used in ground support equipment so that failures resulting from stress corrosion cracking will be prevented is described. A general criteria to be used in designing for resistance to stress corrosion cracking is also provided. Stress corrosion can be defined as combined action of sustained tensile stress and corrosion to cause premature failure of materials. Various aluminum, steels, nickel, titanium and copper alloys, and tempers and corrosive environment are evaluated for stress corrosion cracking.

  15. Microtopographic and depth controls on active layer chemistry in Arctic polygonal ground

    DOE PAGESBeta

    Newman, Brent D.; Throckmorton, Heather M.; Graham, David E.; Gu, Baohua; Hubbard, Susan S.; Liang, Liyuan; Wu, Yuxin; Heikoop, J. M.; Herndon, Elizabeth M.; Phelps, Tommy J.; et al

    2015-03-24

    Polygonal ground is a signature characteristic of Arctic lowlands, and carbon release from permafrost thaw can alter feedbacks to Arctic ecosystems and climate. This study describes the first comprehensive spatial examination of active layer biogeochemistry that extends across high- and low-centered, ice wedge polygons, their features, and with depth. Water chemistry measurements of 54 analytes were made on surface and active layer pore waters collected near Barrow, Alaska, USA. Significant differences were observed between high- and low-centered polygons suggesting that polygon types may be useful for landscape-scale geochemical classification. However, differences were found for polygon features (centers and troughs) formore » analytes that were not significant for polygon type, suggesting that finer-scale features affect biogeochemistry differently from polygon types. Depth variations were also significant, demonstrating important multidimensional aspects of polygonal ground biogeochemistry. These results have major implications for understanding how polygonal ground ecosystems function, and how they may respond to future change.« less

  16. What Controls Methane in Potable Ground Water in the Appalachian Basin?

    NASA Astrophysics Data System (ADS)

    Siegel, D. I.; Smith, B.; Perry, A. E.; Bothun, R.

    2014-12-01

    We present the results of baseline (pre-drilling) sampling for methane in 13,040 potable ground water samples in Northeastern Pennsylvania and 8,004 samples from a "Western Area" (southwest Pennsylvania, eastern Ohio, and north-central West Virginia) that were collected on behalf of Chesapeake Energy Corporation as part of its monitoring program prior to drilling unconventional oil and gas wells in the Marcellus and Utica Formations, as well as the results of a year-long study on temporal variability of methane in ground water at 12 locations in NE Pennsylvania We found dissolved methane common in potable ground water in the Appalachian Basin. In NE Pennsylvania, measureable dissolved methane occurred in 24% of our samples with 3.4% naturally exceeding the PADEP methane notification level of 7 mg/L. In the western area, dissolved methane occurred naturally in 36% of groundwater sampled and in Ohio, 4.1% of samples exceeded the Ohio dissolved methane action level of 10 mg/L. More methane is associated with hydrogeochemical facies trending towards Na-Cl and Na-HCO3 type waters in valleys and along hill flanks. We found no relationship occurs between the concentration of methane and proximity to pre-existing gas wells. Concentrations of methane in domestic wells can naturally vary by factors, depending on pumping regime and time of year.

  17. Hydrologic and biogeochemical controls of river subsurface solutes under agriculturally enhanced ground water flow

    USGS Publications Warehouse

    Wildman, R.A., Jr.; Domagalski, J.L.; Hering, J.G.

    2009-01-01

    The relative influences of hydrologic processes and biogeochemistry on the transport and retention of minor solutes were compared in the riverbed of the lower Merced River (California, USA). The subsurface of this reach receives ground water discharge and surface water infiltration due to an altered hydraulic setting resulting from agricultural irrigation. Filtered ground water samples were collected from 30 drive point locations in March, June, and October 2004. Hydrologic processes, described previously, were verified by observations of bromine concentrations; manganese was used to indicate redox conditions. The separate responses of the minor solutes strontium, barium, uranium, and phosphorus to these influences were examined. Correlation and principal component analyses indicate that hydrologic processes dominate the distribution of trace elements in the ground water. Redox conditions appear to be independent of hydrologic processes and account for most of the remaining data variability. With some variability, major processes are consistent in two sampling transects separated by 100 m. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  18. Faulting arrested by control of ground-water withdrawal in Houston, Texas.

    USGS Publications Warehouse

    Holzer, T.; Gabrysch, R.K.; Verbeek, E.R.

    1983-01-01

    More than 86 historically active faults with an aggregate length of 150 miles have been identified within and adjacent to the Houston, Texas, metropolitan area. Although scarps of these faults grow gradually and without causing damaging earthquakes, historical fault offset has cost millions of dollars in damage to houses and other buildings, utilities, and highways that were built on or across the faults. The historical fault activity results from renewed movement along preexisting faults and appears to be caused principally by withdrawal of ground water for municipal, industrial, and agricultural uses in the Houston area. Approximately one-half of the area's water supply is obtained from local ground water. Monitoring by the US Geological Survey of heights of fault scarps indicates that many of the scarps have recently stopped increasing in height. The area where faulting has ceased coincides with the area where ground-water pumping was cut back in the mid-1970s to slow the damage caused by land subsidence along Galveston Bay and the Houston Ship Channel. Thus, it appears that efforts to halt land subsidence in the coastal area have provided the additional benefit of arresting damaging surface faulting. -from Authors

  19. Design and evaluation of an advanced air-ground data-link system for air traffic control

    NASA Technical Reports Server (NTRS)

    Denbraven, Wim

    1992-01-01

    The design and evaluation of the ground-based portion of an air-ground data-link system for air traffic control (ATC) are described. The system was developed to support the 4D Aircraft/ATC Integration Study, a joint simulation experiment conducted at NASA's Ames and Langley Research Centers. The experiment focused on airborne and ground-based procedures for handling aircraft equipped with a 4D-Flight Management System (FMS) and the system requirements needed to ensure conflict-free traffic flow. The Center/TRACON Automation System (CTAS) at Ames was used for the ATC part of the experiment, and the 4D-FMS-equipped aircraft was simulated by the Transport Systems Research Vehicle (TSRV) simulator at Langley. The data-link system supported not only conventional ATC communications, but also the communications needed to accommodate the 4D-FMS capabilities of advanced aircraft. Of great significance was the synergism gained from integrating the data link with CTAS. Information transmitted via the data link was used to improve the monitoring and analysis capability of CTAS without increasing controller input workload. Conversely, CTAS was used to anticipate and create prototype messages, thus reducing the workload associated with the manual creation of data-link messages.

  20. Using Ground Penetrating Radar to Image Paleotopography and Structural Controls at Coral Pink Sand Dunes, Kane County, Utah

    NASA Astrophysics Data System (ADS)

    Rozar, E. J.; Bradford, J. H.; Ford, R. L.; Wilkins, D. E.

    2014-12-01

    The Coral Pink Sand Dunes (CPSD) are one of the largest dune fields in the Great Basin-Colorado Plateau Transition Zone. The dune field rests on Navajo Sandstone, and is bisected by the Sevier Normal Fault, which also forms the bedrock escarpment along the eastern boundary of the lower dune field (LDF). Limited ground penetrating radar (GPR) collected previously, as well as recent ground-based LiDAR data and geomorphic observations, suggest that underlying bedrock is topographically lower in the center of the LDF than on its margins. In order to image the dune-bedrock interface and any structures contained within the bedrock, including buried faults, 50-MHz and 100-MHz GPR antennae with 400-V transmitters were used to conduct over 25 transects, totaling several kilometers, across the LDF. We recorded radar reflections at depths of up to 30 m within the bedrock beneath the modern dunes. Outcrops and/or shallow boreholes along some transects provide ground truth for dune-bedrock contacts. The resulting radar profiles suggest at least two antithetic fault zones within the LDF that, in places, appear to control the location of smaller dunes. Further examination of the relationship between these fault zones and dune forms, as imaged with LiDAR, will help inform whether or not these structural controls affect variation in dune type and patterning across the LDF, and may also explain why the CPSD exist in this location.

  1. TDRSS data handling and management system study. Ground station systems for data handling and relay satellite control

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Results of a two-phase study of the (Data Handling and Management System DHMS) are presented. An original baseline DHMS is described. Its estimated costs are presented in detail. The DHMS automates the Tracking and Data Relay Satellite System (TDRSS) ground station's functions and handles both the forward and return link user and relay satellite data passing through the station. Direction of the DHMS is effected via a TDRSS Operations Control Central (OCC) that is remotely located. A composite ground station system, a modified DHMS (MDHMS), was conceptually developed. The MDHMS performs both the DHMS and OCC functions. Configurations and costs are presented for systems using minicomputers and midicomputers. It is concluded that a MDHMS should be configured with a combination of the two computer types. The midicomputers provide the system's organizational direction and computational power, and the minicomputers (or interface processors) perform repetitive data handling functions that relieve the midicomputers of these burdensome tasks.

  2. Shale Failure Mechanics and Intervention Measures in Underground Coal Mines: Results From 50 Years of Ground Control Safety Research

    PubMed Central

    2015-01-01

    Ground control research in underground coal mines has been ongoing for over 50 years. One of the most problematic issues in underground coal mines is roof failures associated with weak shale. This paper will present a historical narrative on the research the National Institute for Occupational Safety and Health has conducted in relation to rock mechanics and shale. This paper begins by first discussing how shale is classified in relation to coal mining. Characterizing and planning for weak roof sequences is an important step in developing an engineering solution to prevent roof failures. Next, the failure mechanics associated with the weak characteristics of shale will be discussed. Understanding these failure mechanics also aids in applying the correct engineering solutions. The various solutions that have been implemented in the underground coal mining industry to control the different modes of failure will be summarized. Finally, a discussion on current and future research relating to rock mechanics and shale is presented. The overall goal of the paper is to share the collective ground control experience of controlling roof structures dominated by shale rock in underground coal mining. PMID:26549926

  3. Shale Failure Mechanics and Intervention Measures in Underground Coal Mines: Results From 50 Years of Ground Control Safety Research

    NASA Astrophysics Data System (ADS)

    Murphy, M. M.

    2016-02-01

    Ground control research in underground coal mines has been ongoing for over 50 years. One of the most problematic issues in underground coal mines is roof failures associated with weak shale. This paper will present a historical narrative on the research the National Institute for Occupational Safety and Health has conducted in relation to rock mechanics and shale. This paper begins by first discussing how shale is classified in relation to coal mining. Characterizing and planning for weak roof sequences is an important step in developing an engineering solution to prevent roof failures. Next, the failure mechanics associated with the weak characteristics of shale will be discussed. Understanding these failure mechanics also aids in applying the correct engineering solutions. The various solutions that have been implemented in the underground coal mining industry to control the different modes of failure will be summarized. Finally, a discussion on current and future research relating to rock mechanics and shale is presented. The overall goal of the paper is to share the collective ground control experience of controlling roof structures dominated by shale rock in underground coal mining.

  4. Tug fleet and ground operations schedules and controls. Volume 3: Program cost estimates

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Cost data for the tug DDT&E and operations phases are presented. Option 6 is the recommended option selected from seven options considered and was used as the basis for ground processing estimates. Option 6 provides for processing the tug in a factory clean environment in the low bay area of VAB with subsequent cleaning to visibly clean. The basis and results of the trade study to select Option 6 processing plan is included. Cost estimating methodology, a work breakdown structure, and a dictionary of WBS definitions is also provided.

  5. Environmental hazards of mobile ground spraying with cyanophos and fenthion for quelea control in Senegal.

    PubMed

    Mullié, W C; Diallo, A O; Gadji, B; Ndiaye, M D

    1999-05-01

    Seven roosts of red-billed quelea, Quelea quelea, in the Senegal River Valley and Delta were visited during and after aerial or terrestrial treatments with either Cyanox (cyanophos 500 g a.i. liter-1, five roosts) or Queletox (fenthion 640 g a.i. liter-1, two roosts). The primary goal of the observations was to provide data on environmental effects of cyanophos after mobile ground spraying operations. Twenty-six species of vertebrates (birds, reptile, fish) were found dead or debilitated near the spray sites. Effects on nontarget fauna were most pronounced among owls (cyanophos and fenthion) and blue-naped mousebirds, Urocolius macrourus (fenthion). Among terrestrial invertebrates ants and carabid, and tenebrionid beetles were the most conspicuously affected. Among aquatic invertebrates affected tadpole shrimps, Triops cancriformis, dominated. Extremely high residues were found immediately after spraying on tree leaves in the spillway of a vehicle-mounted Berthoud Super Puma airblast sprayer (up to 1380 mg kg-1) and on birds found dying under these trees (125-11,277 microg bird-1, average 2720 microg bird-1) in two roosts treated with cyanophos. Blue-naped mousebirds were identified as being particularly at risk. Side effects were not dose related. They were most severe after routinely practiced mobile ground spraying applications which led to overdosing. These application methods impose severe environmental hazards, and should be abandoned. PMID:10330314

  6. A Controller-in-the Loop Simulation of Ground-Based Automated Separation Assurance in a NextGen Environment

    NASA Technical Reports Server (NTRS)

    Homola, J.; Prevot, Thomas; Mercer, Joey S.; Brasil, Connie L.; Martin, Lynne Hazel; Cabrall, C.

    2010-01-01

    A controller-in-the-loop simulation was conducted in the Airspace Operations Laboratory (AOL) at the NASA Ames Research Center to investigate the functional allocation aspects associated with ground-based automated separation assurance in a far-term NextGen environment. In this concept, ground-based automation handled the detection and resolution of strategic and tactical conflicts and alerted the controller to deferred situations. The controller was responsible for monitoring the automation and managing situations by exception. This was done in conditions both with and without arrival time constraints across two levels of traffic density. Results showed that although workload increased with an increase in traffic density, it was still manageable in most situations. The number of conflicts increased similarly with a related increase in the issuance of resolution clearances. Although over 99% of conflicts were resolved, operational errors did occur but were tied to local sector complexities. Feedback from the participants revealed that they thought they maintained reasonable situation awareness in this environment, felt that operations were highly acceptable at the lower traffic density level but were less so as it increased, and felt overall that the concept as it was introduced here was a positive step forward to accommodating the more complex environment envisioned as part of NextGen.

  7. Investigation of soil contamination at the Riot Control Burning Pit area in J-Field, Aberdeen Proving Ground, Maryland

    SciTech Connect

    Wang, Ying-Ya; Yuen, C.R.; Martino, L.

    1996-05-01

    A remedial investigation was conducted to identify soil contamination in the Riot Control Burning Pit area in J-field, Aberdeen Proving Ground, Maryland. The investigation included geophysical surveys to delineate the filled section of the pit, soil-gas surveys to locate the organic contamination area, field X-ray fluorescence measurements along the burning pit to identify the major metal contamination, and surface and subsurface soil analyses to investigate the nature and extent of contamination. This paper presents the results of this investigation

  8. Low-Speed Stability-and-Control and Ground-Effects Measurements on the Industry Reference High Speed Civil Transport

    NASA Technical Reports Server (NTRS)

    Kemmerly, Guy T.; Campbell, Bryan A.; Banks, Daniel W.; Yaros, Steven F.

    1999-01-01

    As a part of a national effort to develop an economically feasible High Speed Civil Transport (HSCT), a single configuration has been accepted as the testing baseline by the organizations working in the High Speed Research (HSR) program. The configuration is based on a design developed by the Boeing Company and is referred to as the Reference H (Ref H). The data contained in this report are low-speed stability-and-control and ground-effect measurements obtained on a 0.06 scale model of the Ref H in a subsonic tunnel.

  9. Indicators Developed to Evaluate the International Framework Convention on Tobacco Control in Iran; A Grounded Theory Study

    PubMed Central

    Sarrafzadegan, Nizal; Rabiei, Katayoun; Abedi, Heidarali; Kelishadi, Roya; Fereydoun Mohaseli, Khadijeh; Alavi, Mousa; Roohafza, Hamidreza

    2014-01-01

    This study aimed to develop indicators for evaluating the implementation of The Framework Convention on Tobacco Control (FCTC) in Iran. We used the “grounded theory” framework. Totally, 265 policy-makers, stakeholders, and community members were recruited by purposeful sampling in 2008. After analyzing the gathered data, 251 indicators, including 82 indicators as “applied indicators”, were derived from second-level codes for three groups. A suitable evaluation questionnaire can be designed based on the extracted indicators for policy makers, stakeholders, and the community to follow the implementation of the FCTC in Iran. PMID:24753645

  10. In flight ground control of high drag satellites utilizing on-board accelerometer data and rapid orbit prediction techniques

    NASA Technical Reports Server (NTRS)

    Fuchs, A. J.; Velez, C. E.

    1974-01-01

    High drag satellites frequently require precise verification of orbital maneuvers and the accurate prediction of perigee height. An in-flight ground support system designed to monitor and compute orbital state and maneuvers is described. The use of on-board three-axis accelerometer data in a flight support software system to perform on-line maneuver analysis and atmospheric model updating is discussed. In addition, automated analytic techniques to rapidly and accurately predict perigee height following a maneuver are described, as well as semianalytic averaging techniques designed to predict a decaying orbital state for mission control.

  11. Spaceborne Autonomous and Ground Based Relative Orbit Control for the TerraSAR-X/TanDEM-X Formation

    NASA Technical Reports Server (NTRS)

    Ardaens, J. S.; D'Amico, S.; Kazeminejad, B.; Montenbruck, O.; Gill, E.

    2007-01-01

    . The goal of the ground segment is thus to regularly correct this configuration by performing small orbit correction maneuvers on TDX. The ground station contacts are limited due to the geographic position of the station and the costs for contact time. Only with a polar ground station a contact visibility is possible every orbit for LEO satellites. TSX and TDX use only the Weilheim ground station (in the southern part of Germany) during routine operations. This station allows two scheduled contact per day for the nominal orbit configuration, meaning that the satellite conditions can be checked with an interval of 12 hours. While this limitation is usually not critical for single satellite operations, the visibility constraints drive the achievable orbit control accuracy for a LEO formation if a ground based approach is chosen. Along-track position uncertainties and maneuver execution errors affect the relative motion and can be compensated only after a ground station contact.

  12. The use of oxygen scavengers to prevent the transient discolouration of ground beef packaged under controlled, oxygen-depleted atmospheres.

    PubMed

    Gill, C O; McGinnis, J C

    1995-01-01

    Rates of O(2) absorption from air were determined for a type of commercial O(2) scavenger that is formulated for rapid O(2) absorption at chiller temperatures. Rates of O(2) absorption from N(2) atmospheres containing 600 ppm O(2) were determined for trays that each contained 350 g of ground beef. Packs with controlled atmospheres of N(2) that contained ground beef and O(2) scavengers were prepared, to determine the conditions under which the scavengers could prevent the transient discolouration of the meat which arises from its reaction with the residual O(2) initially present in pack atmospheres. The rates of O(2) absorption by individual scavengers varied from the average by ±50%. The rate of O(2) absorption declined with decreasing oxygen concentration, from an average value per scavenger of about 12 ml h(-1) when O(2) concentrations were between 20 and 10%. At O(2) concentrations <1% (10,000 ppm) the rate of O(2) absorption was directly proportioned to the O(2) concentration so that the O(2) concentration in an atmosphere in a gas-impermeable pouch declined exponentially with time. The absorption of O(2) by ground beef was similarly dependent on the O(2) concentration. At 2 °C, the transient discolouration of beef in atmospheres initially containing about 50 ppm O(2) was prevented by the presence of 17.5 scavengers per l of atmosphere. At -15 °C, discolouration was prevented by 5 scavengers per l. The findings indicate that the O(2) concentration in pack atmospheres has to be reduced below 10 ppm within 30 min at 2 °C, or 2 h at -1.5 °C if ground beef is not to transiently discolour. It is unlikely that the required rates of O(2) absorption could be obtained economically with currently available, commercial O(2) scavengers. PMID:22060109

  13. Summary of hydrogeologic controls on ground-water flow at the Nevada Test Site, Nye County, Nevada

    SciTech Connect

    Laczniak, R.J.; Cole, J.C.; Sawyer, D.A.; Trudeau, D.A.

    1996-07-01

    The underground testing of nuclear devices has generated substantial volumes of radioactive and other chemical contaminants below ground at the Nevada Test Site (NTS). Many of the more radioactive contaminants are highly toxic and are known to persist in the environment for thousands of years. In response to concerns about potential health hazards, the US Department of Energy, under its Environmental Restoration Program, has made NTS the subject of a long-term investigation. Efforts will assess whether byproducts of underground testing pose a potential hazard to the health and safety of the public and, if necessary, will evaluate and implement steps to remediate any of the identified dangers. Ground-water flow is the primary mechanism by which contaminants can be transported significant distances away from the initial point of injection. Flow paths between contaminant sources and potential receptors are separated by remote areas that span tens of miles. The diversity and structural complexity of the rocks along these flow paths complicates the hydrology of the region. Although the hydrology has been studied in some detail, much still remains uncertain about flow rates and directions through the fractured-rock aquifers that transmit water great distances across this arid region. Unique to the hydrology of NTS are the effects of underground testing, which severely alter local rock characteristics and affect hydrologic conditions throughout the region. This report summarizes what is known and inferred about ground-water flow throughout the NTS region. The report identifies and updates what is known about some of the major controls on ground-water flow, highlights some of the uncertainties in the current understanding, and prioritizes some of the technical needs as related to the Environmental Restoration Program. 113 refs.

  14. Spin-orbit coupling controlled ground state in Sr2ScOsO6

    NASA Astrophysics Data System (ADS)

    Taylor, A. E.; Morrow, R.; Fishman, R. S.; Calder, S.; Kolesnikov, A. I.; Lumsden, M. D.; Woodward, P. M.; Christianson, A. D.

    2016-06-01

    We report neutron scattering experiments which reveal a large spin gap in the magnetic excitation spectrum of weakly-monoclinic double perovskite Sr2ScOsO6 . The spin gap is demonstrative of appreciable spin-orbit-induced anisotropy, despite nominally orbitally-quenched 5 d3Os5 + ions. The system is successfully modeled including nearest neighbor interactions in a Heisenberg Hamiltonian with exchange anisotropy. We find that the presence of the spin-orbit-induced anisotropy is essential for the realization of the type I antiferromagnetic ground state. This demonstrates that physics beyond the LS or JJ coupling limits plays an active role in determining the collective properties of 4 d3 and 5 d3 systems and that theoretical treatments must include spin-orbit coupling.

  15. Spin-orbit coupling controlled ground state in Sr2ScOsO6

    DOE PAGESBeta

    Taylor, A. E.; Morrow, R.; Fishman, R. S.; Calder, S.; Kolesnikov, A. I.; Lumsden, M. D.; Woodward, P. M.; Christianson, A. D.

    2016-06-27

    In this paper, we report neutron scattering experiments which reveal a large spin gap in the magnetic excitation spectrum of weakly-monoclinic double perovskite Sr2ScOsO6. The spin gap is demonstrative of appreciable spin-orbit-induced anisotropy, despite nominally orbitally-quenched 5d3Os5+ ions. The system is successfully modeled including nearest neighbor interactions in a Heisenberg Hamiltonian with exchange anisotropy. We find that the presence of the spin-orbit-induced anisotropy is essential for the realization of the type I antiferromagnetic ground state. Finally, this demonstrates that physics beyond the LS or JJ coupling limits plays an active role in determining the collective properties of 4d3 and 5d3more » systems and that theoretical treatments must include spin-orbit coupling.« less

  16. Systems engineering and integration of control centers in support of multiple programs. [ground control for STS payloads and unmanned vehicles

    NASA Technical Reports Server (NTRS)

    Miller, David N.

    1989-01-01

    The NASA Johnson Space Center's new Multiprogram Control Center (MPCC) addresses the control requirements of complex STS payloads as well as unmanned vehicles. An account is given of the relationship of the MPCC to the STS Mission Control Center, with a view to significant difficulties that may be encountered and solutions thus far devised for generic problems. Examples of MPCC workstation applications encompass telemetry decommutation, engineering unit conversion, data-base management, trajectory processing, and flight design.

  17. NASA/MSFC ground experiment for large space structure control verification

    NASA Technical Reports Server (NTRS)

    Waites, H. B.; Seltzer, S. M.; Tollison, D. K.

    1984-01-01

    Marshall Space Flight Center has developed a facility in which closed loop control of Large Space Structures (LSS) can be demonstrated and verified. The main objective of the facility is to verify LSS control system techniques so that on orbit performance can be ensured. The facility consists of an LSS test article which is connected to a payload mounting system that provides control torque commands. It is attached to a base excitation system which will simulate disturbances most likely to occur for Orbiter and DOD payloads. A control computer will contain the calibration software, the reference system, the alignment procedures, the telemetry software, and the control algorithms. The total system will be suspended in such a fashion that LSS test article has the characteristics common to all LSS.

  18. Use of COTS in the Multimission Advanced Ground Intelligent Control (MAGIC) program

    SciTech Connect

    Crowley, N.L.

    1997-11-01

    This tutorial will discuss the experiences of the Space System Technologies Division of the USAF Phillips Laboratory (PL/VTS) in developing a COTS-based satellite control system. The system`s primary use is a testbed for new technologies that are intended for future integration into the operational satellite control system. As such, the control system architecture must be extremely open and flexible so we can integrate new components and functions easily and also provide our system to contractors for their component work. The system is based on commercial hardware, is based on Windows NT, and makes the maximum use of COTS components and industry standards.

  19. On shaky ground - A study of security vulnerabilities in control protocols

    SciTech Connect

    Byres, E. J.; Huffman, D.; Kube, N.

    2006-07-01

    The recent introduction of information technologies such as Ethernet R into nuclear industry control devices has resulted in significantly less isolation from the outside world. This raises the question of whether these systems could be attacked by malware, network hackers or professional criminals to cause disruption to critical operations in a manner similar to the impacts now felt in the business world. To help answer this question, a study was undertaken to test a representative control protocol to determine if it had vulnerabilities that could be exploited. A framework was created in which a test could express a large number of test cases in very compact formal language. This in turn, allowed for the economical automation of both the generation of selectively malformed protocol traffic and the measurement of device under test's (DUT) behavior in response to this traffic. Approximately 5000 protocol conformance tests were run against two major brands of industrial controller. More than 60 categories of errors were discovered, the majority of which were in the form of incorrect error responses to malformed traffic. Several malformed packets however, caused the device to respond or communicate in inappropriate ways. These would be relatively simple for an attacker to inject into a system and could result in the plant operator losing complete view or control of the control device. Based on this relatively small set of devices, we believe that the nuclear industry urgently needs to adopt better security robustness testing of control devices as standard practice. (authors)

  20. Ground demonstration of an optical control system for a space-based sparse-aperture telescope

    NASA Astrophysics Data System (ADS)

    De Young, David B.; Dillow, James; Corcoran, Stephen P.; Andrews, Edwina V.; Yellowhair, Julius; Devries, Kevin

    1998-08-01

    SVS has recently completed a phase II small business innovative research (SBIR) project called low cost space imager (LCSI). As part of the SBIR project, a sparse aperture telescope design concept was developed. This design includes an optical control system capable of correcting the primary segments to within 38 nm piston and 17 nrad tilt as required by the optical tolerance analysis. The optical system utilizes a common secondary and primaries arranged in a Golay-6 configuration. The primaries are spherical, which eliminates the need for translation and rotation control. A laboratory experiment to validate the controls concept has been completed. This experiment culminated in the demonstration of autonomous capture, alignment, and phasing of an optical system with a three segment primary to tolerances consistent with the space optical system. The implementation of the controls scheme in the laboratory experiment is done using Matlab/Simulink for controller design and code generation the code is implemented real-time on a VME based computer system. Closed loop piston control, which utilizes a four-bin sensing scheme, of an actuated mirror to 25 nm RMS mirror motion has been demonstrated. Additionally, autonomous capture and phasing of three segmented primaries has been demonstrated. The technique for the phasing capture involves real-time implementation of image processing techniques to measure the white light fringe visibility in the far field.

  1. Ground demonstration of an optical control system for a space-based sparse aperture telescope

    NASA Astrophysics Data System (ADS)

    De Young, David B.; Dillow, James; Corcoran, Stephen; Andrews, Edwina V.; Yellowhair, Julius; Devries, Kevin

    1998-09-01

    SVS has recently completed a phase II small business innovative research (SBIR) project called Low Cost Space Imager. As part of the SBIR project, a sparse aperture telescope design concept was developed. This design includes an optical control system capable of correcting the primary segments to within 38 nm piston and 17 nrad tilt as required by the optical tolerance analysis. The optical system utilizes a common secondary and primaries arranged in a Golay-6 configuration. The primaries are spherical, which eliminates the need for translation and rotation control. A laboratory experiment to validate the controls concept has ben completed. This experiment culminated in the demonstration of autonomous capture, alignment, and phasing of an optical system with a three segment primary to tolerances consistent with the space optical system. The implementation of the controls scheme in the laboratory experiment is done using Matlab/Simulink for controller design and code generation. The code is implemented real- time on a VME based computer system. Closed loop piston control, which utilizes a four-bin sensing scheme, of an actuated mirror to 25 nm RMS mirror motion has been demonstrated. Additionally, autonomous capture and phasing of three segmented primaries has been demonstrated. The technique for the phasing capture involves real-time implementation of image processing techniques to measure the white light fringe visibility in the far field.

  2. The role of unattended ground sensors (UGS) in regional confidence building and arms control

    SciTech Connect

    Vannoni, M.; Duggan, R.

    1997-03-01

    Although the Cold War has ended, the world has not become more peaceful. Without the stability provided by an international system dominated by two super-powers, local conflicts are more likely to escalate. Agreements to counter destabilizing pressures in regional conflicts can benefit from the use of cooperative monitoring. Cooperative monitoring is the collecting, analyzing, and sharing of information among parties to an agreement. Ground sensor technologies can contribute to the collection of relevant information. If implemented with consideration for local conditions, cooperative monitoring can build confidence, strengthen existing agreements, and set the stage for continued progress. This presentation describes two examples: the Israeli-Egyptian Sinai agreements of the 1970s and a conceptual example for the contemporary Korean Peninsula. The Sinai was a precedent for the successful use of UGS within the context of cooperative monitoring. The Korean Peninsula is the world`s largest military confrontation. Future confidence building measures that address the security needs of both countries could decrease the danger of conflict and help create an environment for a peace agreement.

  3. Migration strategies for service-enabling ground control stations for unmanned systems

    NASA Astrophysics Data System (ADS)

    Kroculick, Joseph B.

    2011-06-01

    Future unmanned systems will be integrated into the Global Information Grid (GIG) and support net-centric data sharing, where information in a domain is exposed to a wide variety of GIG stakeholders that can make use of the information provided. Adopting a Service-Oriented Architecture (SOA) approach to package reusable UAV control station functionality into common control services provides a number of benefits including enabling dynamic plug and play of components depending on changing mission requirements, supporting information sharing to the enterprise, and integrating information from authoritative sources such as mission planners with the UAV control stations data model. It also allows the wider enterprise community to use the services provided by unmanned systems and improve data quality to support more effective decision-making. We explore current challenges in migrating UAV control systems that manage multiple types of vehicles to a Service-Oriented Architecture (SOA). Service-oriented analysis involves reviewing legacy systems and determining which components can be made into a service. Existing UAV control stations provide audio/visual, navigation, and vehicle health and status information that are useful to C4I systems. However, many were designed to be closed systems with proprietary software and hardware implementations, message formats, and specific mission requirements. An architecture analysis can be performed that reviews legacy systems and determines which components can be made into a service. A phased SOA adoption approach can then be developed that improves system interoperability.

  4. Thermal control for the ground simulation of a space IR sensor system

    NASA Technical Reports Server (NTRS)

    Lee, E.; Warren, A.; Gasser, G.; Tierney, M.

    1990-01-01

    Active and passive thermal controls for simulations of a space IR sensor system operating in cryogenic temperatures were designed, built, and tested from a component level to a system level. The test results from component tests and integrated system tests have compared very well with theoretical predictions, and thus verify component and integrated thermal math models. These verified models can be modified for use to predict flight systems thermal performance. Thermal vacuum simulations and demonstrations of a space IR system consisted of a target and background scene generator, telescope mirrors supported by a graphite-epoxy metering structure, and an IR sensor. These components are required to operate at cryogenic temperature levels. Each component has its unique thermal control needs. Descriptions are presented of thermal control systems for the test article from component design level to integrated system level along with discussions of component and integrated demonstration tests, and correlation of test data with thermal finite difference models.

  5. Transportable Payload Operations Control Center reusable software: Building blocks for quality ground data systems

    NASA Technical Reports Server (NTRS)

    Mahmot, Ron; Koslosky, John T.; Beach, Edward; Schwarz, Barbara

    1994-01-01

    The Mission Operations Division (MOD) at Goddard Space Flight Center builds Mission Operations Centers which are used by Flight Operations Teams to monitor and control satellites. Reducing system life cycle costs through software reuse has always been a priority of the MOD. The MOD's Transportable Payload Operations Control Center development team established an extensive library of 14 subsystems with over 100,000 delivered source instructions of reusable, generic software components. Nine TPOCC-based control centers to date support 11 satellites and achieved an average software reuse level of more than 75 percent. This paper shares experiences of how the TPOCC building blocks were developed and how building block developer's, mission development teams, and users are all part of the process.

  6. Preliminary estimates of range measurements to a spacecraft by means of ground digitally controlled oscillators

    NASA Technical Reports Server (NTRS)

    Liu, A.; Pease, G.

    1974-01-01

    Range measurements to the Pioneer 10 and Mariner 10 spacecraft were made, without the use of a ranging system per se, by using the Jet Propulsion Laboratory Deep Space Network's new digitally controlled oscillator (DCO) device. These measurements were accomplished by controlling the linear ramps of the transmitted carrier frequency with a recently installed DCO instrument at the Goldstone facility and analyzing the received linearly ramped Doppler data with a computer program. The accuracy of these range measurements is on the order of 1.5 km.

  7. Environmental Impact of Controlled-Source Explosions in Ethiopia (Project EAGLE): Surface Shaking, Ground Velocities, and Effects on Buildings

    NASA Astrophysics Data System (ADS)

    Les, A.; Klemperer, S. L.; Keranen, K.; Khan, A.; Maguire, P.

    2003-12-01

    In January 2003, as part of the Ethiopia-Afar Geoscientific Lithospheric Experiment (EAGLE) we conducted a refraction and wide-angle reflection survey of the Main Ethiopian Rift. 757 RefTek "Texan" seismographs with vertical geophones were deployed in 400 km-long axial and cross-rift lines, with another 231 in a central 3D array 100 km in diameter. An 80-instrument passive array of intermediate and broadband sensors was active during our experiment. We recorded 19 borehole shots loaded in nominal 50-meter boreholes, 2 quarry shots, and 2 lake shots. The shots ranged in size from 50-5750 kg, with the most common shot size being 1 tonne. Prior to loading each shot-hole, we measured distances between shots and the nearest structure, typically un-reinforced mud-and-wood houses, occasionally concrete irrigation ditches and aqueducts. We then used semi-empirical formulae derived by Oriard (Hendron and Oriard, 1972) to calculate expected maximum and minimum bounds on ground velocity at these structures, and selected an appropriate shot size to keep the predicted velocity below the "threshold for cosmetic damage", or 2 inches per second, at the most vulnerable structure. The Oriard formulae are derived from measurements associated with blasting for mining and civil engineering purposes and may not accurately predict the ground velocity from the source depths and explosive type used in the EAGLE and other controlled-source experiments. A detailed, trace-by-trace analysis of maximum ground velocities at our closest seismographs can provide data that will be useful in planning future large-scale seismic experiments. Preliminary results from traces within 20 km of our borehole shots suggest that maximum recorded ground velocities were within or below the maximum-minimum range predicted by Oriard, and hence that larger shot sizes could have been used with acceptable risks. A lake shot fired at the optimum depth (84 m for a 1 tonne shot) produced ground velocities that exceeded

  8. The control system of the 12-m medium-size telescope prototype: a test-ground for the CTA array control

    NASA Astrophysics Data System (ADS)

    Oya, I.; Anguner, E. A.; Behera, B.; Birsin, E.; Fuessling, M.; Lindemann, R.; Melkumyan, D.; Schlenstedt, S.; Schmidt, T.; Schwanke, U.; Sternberger, R.; Wegner, P.; Wiesand, S.

    2014-07-01

    The Cherenkov Telescope Array (CTA) will be the next generation ground-based very-high energy -ray observatory. CTA will consist of two arrays: one in the Northern hemisphere composed of about 20 telescopes, and the other one in the Southern hemisphere composed of about 100 telescopes, both arrays containing telescopes of different sizes and types and in addition numerous auxiliary devices. In order to provide a test-ground for the CTA array control, the steering software of the 12-m medium size telescope (MST) prototype deployed in Berlin has been implemented using the tools and design concepts under consideration to be used for the control of the CTA array. The prototype control system is implemented based on the Atacama Large Millimeter/submillimeter Array (ALMA) Common Software (ACS) control middleware, with components implemented in Java, C++ and Python. The interfacing to the hardware is standardized via the Object Linking and Embedding for Process Control Unified Architecture (OPC UA). In order to access the OPC UA servers from the ACS framework in a common way, a library has been developed that allows to tie the OPC UA server nodes, methods and events to the equivalents in ACS components. The front-end of the archive system is able to identify the deployed components and to perform the sampling of the monitoring points of each component following time and value change triggers according to the selected configurations. The back-end of the archive system of the prototype is composed by two different databases: MySQL and MongoDB. MySQL has been selected as storage of the system configurations, while MongoDB is used to have an efficient storage of device monitoring data, CCD images, logging and alarm information. In this contribution, the details and conclusions on the implementation of the control software of the MST prototype are presented.

  9. The administration`s arms control agenda: Gaining ground under fire

    SciTech Connect

    Holum, J.D.

    1996-03-01

    Its perhaps too easy to forget that Russia is still one country that could inflict overwhelming nuclear devastation on the United States. Russia`s Dumas elections and presidential elections speaks of changes in Russia, but this transformation will take many years and requires our consistent engagement and steady support. The author examines the Clinton Administration`s arms control agenda.

  10. Ground Truthing the ‘Conventional Wisdom’ of Lead Corrosion Control Using Mineralogical Analysis

    EPA Science Inventory

    For drinking water distribution systems (DWDS) with lead-bearing plumbing materials some form of corrosion control is typically necessary, with the goal of mitigating lead release by forming adherent, stable corrosion scales composed of low-solubility mineral phases. Conventional...

  11. Ground Truthing the 'Conventional Wisdom' of Lead Corrosion Control Using Mineralogical Analysis

    EPA Science Inventory

    For drinking water distribution systems (DWDS) with lead-bearing plumbing materials some form of corrosion control is typically necessary, with the goal of mitigating lead release by forming adherent, stable corrosion scales composed of low-solubility mineral phases. Conventional...

  12. Investigating Hydrogeologic Controls on Sandhill Wetlands in Covered Karst with 2D Resistivity and Ground Penetrating Radar

    NASA Astrophysics Data System (ADS)

    Downs, C. M.; Nowicki, R. S.; Rains, M. C.; Kruse, S.

    2015-12-01

    In west-central Florida, wetland and lake distribution is strongly controlled by karst landforms. Sandhill wetlands and lakes are sand-filled upland basins whose water levels are groundwater driven. Lake dimensions only reach wetland edges during extreme precipitation events. Current wetland classification schemes are inappropriate for identifying sandhill wetlands due to their unique hydrologic regime and ecologic expression. As a result, it is difficult to determine whether or not a wetland is impacted by groundwater pumping, development, and climate change. A better understanding of subsurface structures and how they control the hydrologic regime is necessary for development of an identification and monitoring protocol. Long-term studies record vegetation diversity and distribution, shallow ground water levels and surface water levels. The overall goals are to determine the hydrologic controls (groundwater, seepage, surface water inputs). Most recently a series of geophysical surveys was conducted at select sites in Hernando and Pasco County, Florida. Electrical resistivity and ground penetrating radar were employed to image sand-filled basins and the top of the limestone bedrock and stratigraphy of wetland slopes, respectively. The deepest extent of these sand-filled basins is generally reflected in topography as shallow depressions. Resistivity along inundated wetlands suggests the pools are surface expressions of the surficial aquifer. However, possible breaches in confining clay layers beneath topographic highs between depressions are seen in resistivity profiles as conductive anomalies and in GPR as interruptions in otherwise continuous horizons. These data occur at sites where unconfined and confined water levels are in agreement, suggesting communication between shallow and deep groundwater. Wetland plants are observed outside the historic wetland boundary at many sites, GPR profiles show near-surface layers dipping towards the wetlands at a shallower

  13. Response of ground-water levels of flood control operations in three basins, south-eastern Florida

    USGS Publications Warehouse

    Pitt, William A.J.

    1974-01-01

    Three basins in southeastern Florida were investigated to determine the changes in ground-water levels and canal flows that occurred in response to operation of coastal water-control structures in each canal. All three basins are underlain by the Biscayne aquifer. They are, Snapper Creek Canal basin, where the Biscayne aquifer is of high permeability; the Snake Creek Canal basin, where the aquifer is of moderate permeability; and the Pompano-Cypress Canal basin, where the aquifer is of low permeability. In each basin, drainage is a function of permeability; thus, where the permeability of the aquifer is high, drainage is excellent. The coastal water-conrol structures are intended to afford flood protection in the three basins. In general the control operation criteria for flood control in newly developing areas in southeastern Florida do not provide adequate protection from flooding because of the time required for the aquifer to respond to changes in the controls. Adequate protection would require increasing the density of secondary drainage canals, but this could achieved only by reducing the quantity of water available for recharging those segments of the Biscayne aquifer adjacent to the canals. (Woodrad-USGS)

  14. Effect of spaceflight hardware on the skeletal properties of ground control mice

    NASA Astrophysics Data System (ADS)

    Bateman, Ted; Lloyd, Shane; Dunlap, Alex; Ferguson, Virginia; Simske, Steven; Stodieck, Louis; Livingston, Eric

    Introduction: Spaceflight experiments using mouse or rat models require habitats that are specifically designed for the microgravity environment. During spaceflight, rodents are housed in a specially designed stainless steel meshed cage with gravity-independent food and water delivery systems and constant airflow to push floating urine and feces towards a waste filter. Differences in the housing environment alone, not even considering the spaceflight environment itself, may lead to physiological changes in the animals contained within. It is important to characterize these cage differences so that results from spaceflight experiments can be more reliably compared to studies from other laboratories. Methods: For this study, we examined the effect of NASA's Animal Enclosure Module (AEM) spaceflight hardware on the skeletal properties of 8-week-old female C57BL/6J mice. This 13-day experiment, conducted on the ground, modeled the flight experiment profile of the CBTM-01 payload on STS-108, with standard vivarium-housed mice being compared to AEM-housed mice (n = 12/group). Functional differences were compared via mechanical testing, micro-hardness indentation, microcomputed tomography, and mineral/matrix composition. Cellular changes were examined by serum chemistry, histology, quantitative histomorphometry, and RT-PCR. A Student's t-test was utilized, with the level of Type I error set at 95 Results: There was no change in elastic, maximum, or fracture force mechanical properties at the femur mid-diaphysis, however, structural stiffness was -17.5 Conclusions: Housing mice in the AEM spaceflight hardware had minimal effects on femur cortical bone properties. However, trabecular bone at the proximal tibia in AEM mice experi-enced large increases in microarchitecture and mineral composition. Increases in bone density were accompanied by reductions in bone-forming osteoblasts and bone-resorbing osteoclasts, representing a general decline in bone turnover at this site

  15. IT Security Support for the Spaceport Command Control Systems Development Ground Support Development Operations

    NASA Technical Reports Server (NTRS)

    Branch, Drew A.

    2014-01-01

    Security is one of the most if not the most important areas today. After the several attacks on the United States, security everywhere has heightened from airports to the communication among the military branches legionnaires. With advanced persistent threats (APT's) on the rise following Stuxnet, government branches and agencies are required, more than ever, to follow several standards, policies and procedures to reduce the likelihood of a breach. Attack vectors today are very advanced and are going to continue to get more and more advanced as security controls advance. This creates a need for networks and systems to be in an updated and secured state in a launch control system environment. FISMA is a law that is mandated by the government to follow when government agencies secure networks and devices. My role on this project is to ensure network devices and systems are in compliance with NIST, as outlined in FISMA. I will achieve this by providing assistance with security plan documentation and collection, system hardware and software inventory, malicious code and malware scanning, and configuration of network devices i.e. routers and IDS's/IPS's. In addition, I will be completing security assessments on software and hardware, vulnerability assessments and reporting, and conducting patch management and risk assessments. A guideline that will help with compliance with NIST is the SANS Top 20 Critical Controls. SANS Top 20 Critical Controls as well as numerous security tools, security software and the conduction of research will be used to successfully complete the tasks given to me. This will ensure compliance with FISMA and NIST, secure systems and a secured network. By the end of this project, I hope to have carried out the tasks stated above as well as gain an immense knowledge about compliance, security tools, networks and network devices, as well as policies and procedures.

  16. IT Security Support for the Spaceport Command Control Systems Development Ground Support Development Operations

    NASA Technical Reports Server (NTRS)

    Branch, Drew

    2013-01-01

    Security is one of the most if not the most important areas today. After the several attacks on the United States, security everywhere was heightened from Airports to the communication among the military branches legionnaires. With advanced persistent threats (APTs) on the rise following Stuxnet, government branches and agencies are required, more than ever, to follow several standards, policies and procedures to reduce the likelihood of a breach. Attack vectors today are very advanced and are going to continue to get more and more advanced as security controls advance. This creates a need for networks and systems to be in an updated and secured state in a launch control system environment. FISMA is a law that is mandated by the government to follow when government agencies secure networks and devices. My role on this project is to ensure network devices and systems are in compliance with NIST, as outlined in FISMA. I will achieve this by providing assistance with security plan documentation and collection, system hardware and software inventory, malicious code and malware scanning and configuration of network devices i.e. routers and IDSsIPSs. In addition I will be completing security assessments on software and hardware, vulnerability assessments and reporting, conducting patch management and risk assessments. A guideline that will help with compliance with NIST is the SANS Top 20 Critical Controls. SANS Top 20 Critical Controls as well as numerous security tools, security software and the conduction of research will be used to successfully complete the tasks given to me. This will ensure compliance with FISMA and NIST, secure systems and a secured network. By the end of this project, I hope to have carried out stated above as well as gain an immense knowledge about compliance, security tools, networks and network devices, policies and procedures.

  17. Dried, ground banana plant leaves (Musa spp.) for the control of Haemonchus contortus and Trichostrongylus colubriformis infections in sheep.

    PubMed

    Gregory, L; Yoshihara, E; Ribeiro, B L M; Silva, L K F; Marques, E C; Meira, E B S; Rossi, R S; Sampaio, P H; Louvandini, H; Hasegawa, M Y

    2015-12-01

    To evaluate the anthelmintic effect of Musa spp. leaves, 12 animals were artificially infected with Haemonchus contortus, and another 12 animals were infected with Trichostrongylus colubriformis. Then, both treatment groups were offered 400 g of dried ground banana plant leaves, and the control animals were offered only 1000 g of coast cross hay. During the trials, the animals received weekly physical examinations. The methods used to evaluate the efficiency of this treatment were packed cell volume, total plasma protein and faecal egg counts, and egg hatchability tests were performed on days -2, +3, +6, +9, +13 and +15. Coproculture tests were performed on day -2 to confirm monospecific infections. In the FEC and EHT, a statistically significant difference (0.04, 0.005; p < 0.05) was noted for T. colubriformis. There were no statistically significant differences (p > 0.05) for Haemochus contortus group in all tests. Our results confirmed previous findings suggesting that dried ground banana plant leaves possess anthelmintic activity. PMID:26350377

  18. Integrated Vehicle Ground Vibration Testing in Support of Launch Vehicle Loads and Controls Analysis

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret L.; Chenevert, Donald J.

    2009-01-01

    NASA has conducted dynamic tests on each major launch vehicle during the past 45 years. Each test provided invaluable data to correlate and correct analytical models. GVTs result in hardware changes to Saturn and Space Shuttle, ensuring crew and vehicle safety. Ares I IVGT will provide test data such as natural frequencies, mode shapes, and damping to support successful Ares I flights. Testing will support controls analysis by providing data to reduce model uncertainty. Value of testing proven by past launch vehicle successes and failures. Performing dynamic testing on Ares vehicles will provide confidence that the launch vehicles will be safe and successful in their missions.

  19. Pockels cover for switchable control of the reflection from a grounded, isotropic, lossy dielectric slab

    NASA Astrophysics Data System (ADS)

    Valagiannopoulos, C. A.; Tsitsas, N. L.; Lakhtakia, A.; Burger, A.

    2015-02-01

    Theoretical analysis indicates that the reflection of obliquely incident light with arbitrary polarization state in the mid-wavelength (3-8 μm) and long-wavelength (8-15 μm) infrared regimes by a lossy, isotropic, dielectric slab backed by a perfect electric conductor can be electrically controlled by covering the dielectric slab by an epitaxial layer of cubic noncentrosymmetric materials, which are normally isotropic dielectric but display the Pockels effect. The reflectances change on the application of a dc electric field parallel to thickness direction of the Pockels cover, without causing depolarization.

  20. Optimising UAV topographic surveys processed with structure-from-motion: Ground control quality, quantity and bundle adjustment

    NASA Astrophysics Data System (ADS)

    James, Mike R.; Robson, Stuart; d'Oleire-Oltmanns, Sebastian; Niethammer, Uwe

    2016-04-01

    Structure-from-motion (SfM) algorithms are greatly facilitating the production of detailed topographic models based on images collected by unmanned aerial vehicles (UAVs). However, SfM-based software does not generally provide the rigorous photogrammetric analysis required to fully understand survey quality. Consequently, error related to problems in control point data or the distribution of control points can remain undiscovered. Even if these errors are not large in magnitude, they can be systematic, and thus have strong implications for the use of products such as digital elevation models (DEMs) and orthophotos. Here, we develop a Monte Carlo approach to (1) improve the accuracy of products when SfM-based processing is used and (2) reduce the associated field effort by identifying suitable lower density deployments of ground control points. The method highlights over-parameterisation during camera self-calibration and provides enhanced insight into control point performance when rigorous error metrics are not available. Processing was implemented using commonly-used SfM-based software (Agisoft PhotoScan), which we augment with semi-automated and automated GCPs image measurement. We apply the Monte Carlo method to two contrasting case studies - an erosion gully survey (Taurodont, Morocco) carried out with an fixed-wing UAV, and an active landslide survey (Super-Sauze, France), acquired using a manually controlled quadcopter. The results highlight the differences in the control requirements for the two sites, and we explore the implications for future surveys. We illustrate DEM sensitivity to critical processing parameters and show how the use of appropriate parameter values increases DEM repeatability and reduces the spatial variability of error due to processing artefacts.

  1. Experiences with a Requirements-Based Programming Approach to the Development of a NASA Autonomous Ground Control System

    NASA Technical Reports Server (NTRS)

    Hinchey, Michael G.; Rash, James L.; Rouff, Christopher A.; Gracanin, Denis; Erickson, John

    2005-01-01

    Requirements-to-Design-to-Code (R2D2C) is an approach to the engineering of computer-based systems that embodies the idea of requirements-based programming in system development. It goes further; however, in that the approach offers not only an underlying formalism, but full formal development from requirements capture through to the automatic generation of provably-correct code. As such, the approach has direct application to the development of systems requiring autonomic properties. We describe a prototype tool to support the method, and illustrate its applicability to the development of LOGOS, a NASA autonomous ground control system, which exhibits autonomic behavior. Finally, we briefly discuss other areas where the approach and prototype tool are being considered for application.

  2. Ergonomic problems regarding the interactive touch input via screens in onboard and ground-based flight control

    NASA Technical Reports Server (NTRS)

    Holzhausen, K. P.; Gaertner, K. P.

    1985-01-01

    A significant problem concerning the integration of display and switching functions is related to the fact that numerous informative data which have to be processed by man must be read from only a few display devices. A satisfactory ergonomic design of integrated display devices and keyboards is in many cases difficult, because not all functions which can be displayed and selected are simultaneously available. A technical solution which provides an integration of display and functional elements on the basis of the highest flexibility is obtained by using a cathode ray tube with a touch-sensitive screen. The employment of an integrated data input/output system is demonstrated for the cases of onboard and ground-based flight control. Ergonomic studies conducted to investigate the suitability of an employment of touch-sensitive screens are also discussed.

  3. Estimating porosity with ground-penetrating radar reflection tomography: A controlled 3-D experiment at the Boise Hydrogeophysical Research Site

    NASA Astrophysics Data System (ADS)

    Bradford, John H.; Clement, William P.; Barrash, Warren

    2009-04-01

    To evaluate the uncertainty of water-saturated sediment velocity and porosity estimates derived from surface-based, ground-penetrating radar reflection tomography, we conducted a controlled field experiment at the Boise Hydrogeophysical Research Site (BHRS). The BHRS is an experimental well field located near Boise, Idaho. The experimental data set consisted of 3-D multioffset radar acquired on an orthogonal 20 × 30 m surface grid that encompassed a set of 13 boreholes. Experimental control included (1) 1-D vertical velocity functions determined from traveltime inversion of vertical radar profiles (VRP) and (2) neutron porosity logs. We estimated the porosity distribution in the saturated zone using both the Topp and Complex Refractive Index Method (CRIM) equations and found the CRIM estimates in better agreement with the neutron logs. We found that when averaged over the length of the borehole, surface-derived velocity measurements were within 5% of the VRP velocities and that the porosity differed from the neutron log by less than 0.05. The uncertainty, however, is scale dependent. We found that the standard deviation of differences between ground-penetrating-radar-derived and neutron-log-derived porosity values was as high as 0.06 at an averaging length of 0.25 m but decreased to less than 0.02 at length scale of 11 m. Additionally, we used the 3-D porosity distribution to identify a relatively high-porosity anomaly (i.e., local sedimentary body) within a lower-porosity unit and verified the presence of the anomaly using the neutron porosity logs. Since the reflection tomography approach requires only surface data, it can provide rapid assessment of bulk hydrologic properties, identify meter-scale anomalies of hydrologic significance, and may provide input for other higher-resolution measurement methods.

  4. Ground-based LiDAR integration with avalanche control operations: target planning and assessment of control effectiveness

    NASA Astrophysics Data System (ADS)

    Deems, J. S.; LeWinter, A.; Gadomski, P. J.; Finnegan, D. C.

    2015-12-01

    The varying distribution of snow depth in avalanche starting zones exerts a strong influence on avalanche potential and character. Extreme depth changes over short distances are common, especially in wind-affected, above-treeline environments. Snow depth also affects the ease of avalanche triggering. Experience shows that avalanche reduction efforts are often more successful when targeting shallow trigger point areas near deeper slabs with explosives or ski cutting. We are exploring the use of high resolution snow depth and depth change maps from differential LiDAR scans to quantify loading patterns for use in both pre-control planning and in post-control assessment. We present results from our ongoing work at the Arapahoe Basin and Aspen Highlands ski areas in Colorado, USA, and from a new collaboration with the Colorado Department of Transportation. At Arapahoe Basin we have tested rapid snow depth product generation for use in planning placement of explosives for artificial avalanche triggering. At Aspen Highlands we have explored measurement of minimum disturbance depth from bootpacking. In a new application, we are assessing avalanche hazard reduction with new Gazex exploder arrays on Loveland and Berthoud Passes.

  5. Ground tests for vision based determination and control of formation flying spacecraft trajectories

    NASA Astrophysics Data System (ADS)

    Gasbarri, P.; Sabatini, M.; Palmerini, G. B.

    2014-09-01

    The advances in the computational capabilities and in the robustness of the dedicated algorithms are suggesting vision based techniques as a fundamental asset in performing space operations such as rendezvous, docking and on-orbit servicing. This paper discusses a vision based technique in a scenario where the chaser satellite must identify a non-cooperative target, and use visual information to estimate the relative kinematic state. A hardware-in-the-loop experiment is performed to test the possibility to perform a space rendezvous using the camera as a standalone sensor. This is accomplished using a dedicated test bed constituted by a dark room hosting a robotic manipulator. The camera is mounted on the end effector that moves replicating the satellite formation dynamics, including the control actions, which depend at each time step by the state estimation based on the visual algorithm, thus realizing a closed GNC loop.

  6. A wind-tunnel investigation of parameters affecting helicopter directional control at low speeds in ground effect

    NASA Technical Reports Server (NTRS)

    Yeager, W. T., Jr.; Young, W. H., Jr.; Mantay, W. R.

    1974-01-01

    An investigation was conducted in the Langley full-scale tunnel to measure the performance of several helicopter tail-rotor/fin configurations with regard to directional control problems encountered at low speeds in ground effect. Tests were conducted at wind azimuths of 0 deg to 360 deg in increments of 30 deg and 60 deg and at wind speeds from 0 to 35 knots. The results indicate that at certain combinations of wind speed and wind azimuth, large increases in adverse fin force require correspondingly large increases in the tail-rotor thrust, collective pitch, and power required to maintain yaw trim. Changing the tail-rotor direction of rotation to top blade aft for either a pusher tail rotor (tail-rotor wake blowing away from fin) or a tractor tail rotor (tail-rotor wake blowing against fin) will alleviate this problem. For a pusher tail rotor at 180 deg wind azimuth, increases in the fin/tail-rotor gap were not found to have any significant influence on the overall vehicle directional control capability. Changing the tail rotor to a higher position was found to improve tail-rotor performance for a fin-off configuration at a wind azimuth of 180 deg. A V-tail configuration with a pusher tail rotor with top blade aft direction of rotation was found to be the best configuration with regard to overall directional control capability.

  7. Autonomous and Remote-Controlled Airborne and Ground-Based Robotic Platforms for Adaptive Geophysical Surveying

    NASA Astrophysics Data System (ADS)

    Spritzer, J. M.; Phelps, G. A.

    2011-12-01

    Low-cost autonomous and remote-controlled robotic platforms have opened the door to precision-guided geophysical surveying. Over the past two years, the U.S. Geological Survey, Senseta, NASA Ames Research Center, and Carnegie Mellon University Silicon Valley, have developed and deployed small autonomous and remotely controlled vehicles for geophysical investigations. The purpose of this line of investigation is to 1) increase the analytical capability, resolution, and repeatability, and 2) decrease the time, and potentially the cost and map-power necessary to conduct near-surface geophysical surveys. Current technology has advanced to the point where vehicles can perform geophysical surveys autonomously, freeing the geoscientist to process and analyze the incoming data in near-real time. This has enabled geoscientists to monitor survey parameters; process, analyze and interpret the incoming data; and test geophysical models in the same field session. This new approach, termed adaptive surveying, provides the geoscientist with choices of how the remainder of the survey should be conducted. Autonomous vehicles follow pre-programmed survey paths, which can be utilized to easily repeat surveys on the same path over large areas without the operator fatigue and error that plague man-powered surveys. While initial deployments with autonomous systems required a larger field crew than a man-powered survey, over time operational experience costs and man power requirements will decrease. Using a low-cost, commercially available chassis as the base for autonomous surveying robotic systems promise to provide higher precision and efficiency than human-powered techniques. An experimental survey successfully demonstrated the adaptive techniques described. A magnetic sensor was mounted on a small rover, which autonomously drove a prescribed course designed to provide an overview of the study area. Magnetic data was relayed to the base station periodically, processed and gridded. A

  8. Controls on variability in surface and ground waters in a headwater catchment

    NASA Astrophysics Data System (ADS)

    McMillan, Hilary; Srinivasan, MS

    2014-05-01

    Hydrologists recognise the importance of vertical drainage and deep flow paths in runoff generation, even in headwater catchments. Therefore, characterisation of the joint surfacewater-groundwater system is needed to improve hydrological understanding and model representation. Both soil and groundwater stores are highly variable over multiple scales, and the distribution of water has a strong control on flow rates and timing. In this study, we instrumented an upland headwater catchment in New Zealand to measure the spatial variation in unsaturated and saturated-zone responses. Over a period of 16 months we measured continuous soil moisture at 32 locations and near-surface water table (< 2 m) at 14 locations, with varied aspects, hillslope position and distance from stream, as well as recording streamflow at 3 gauges. In this presentation we describe the controls, types and implications of variability. Our results showed several distinct causes of variability in water stores. Some types of variability involve a response of only part of the catchment to a rainfall event, e.g. partial response of deep soils in the summer months. Other types of variability involve differences in dynamics, e.g. recession shapes; or differences in response rates in different parts of the catchment, e.g. timing of winter wet-up, and a distinctive split between slow and fast groundwater responses. A further type of variability occurs when some parts of the catchment respond more strongly than others, as in the partial saturation responses seen in winter. Soil moisture and water table show different variability characteristics. Soil moisture on the North facing slope is qualitatively different to that on the South facing slope: it does not have the long winter plateau seen on the South facing slope. Groundwater variability appears to be more location specific, with both North and South facing slopes showing a combination of fast and slow water table responses to rainfall events. The many

  9. Ground-Based Testing of Replacement Thermal Control Materials for the Hubble Space Telescope

    NASA Technical Reports Server (NTRS)

    Townsend, Jacqueline A.; Hansen, Patricia A.; McClendon, Mark W.; deGroh, Kim K.; Banks, Bruce A.; Triolo, Jack J.

    1998-01-01

    The mechanical and optical properties of the metallized Teflon FEP thermal control materials on the Hubble Space Telescope (HST) have degraded over the nearly seven years the telescope has been in orbit. Given the damage to the outer layer of the multi-layer insulation (MLI) that was apparent during the second servicing mission (SM2), the decision was made to replace the outer layer during subsequent servicing missions. A Failure Review Board was established to investigate the damage to the MLI and identify a replacement material. The replacement material had to meet the stringent thermal requirements of the spacecraft and maintain mechanical integrity for at least ten years. Ten candidate materials were selected and exposed to ten-year HST-equivalent doses of simulated orbital environments. Samples of the candidates were exposed sequentially to low and high energy electrons and protons, atomic oxygen, x-ray radiation, ultraviolet radiation and thermal cycling. Following the exposures, the mechanical integrity and optical properties of the candidates were investigated using Optical Microscopy, Scanning Electron Microscopy (SEM), a Laboratory Portable Spectroreflectometer (LPSR) and a Lambda 9 Spectroreflectometer. Based on the results of these simulations and analyses, the Failure Review Board selected a replacement material and two alternates that showed the highest likelihood of providing the requisite thermal properties and surviving for ten years in orbit.

  10. Human-Automation Interaction Design for Adaptive Cruise Control Systems of Ground Vehicles.

    PubMed

    Eom, Hwisoo; Lee, Sang Hun

    2015-01-01

    A majority of recently developed advanced vehicles have been equipped with various automated driver assistance systems, such as adaptive cruise control (ACC) and lane keeping assistance systems. ACC systems have several operational modes, and drivers can be unaware of the mode in which they are operating. Because mode confusion is a significant human error factor that contributes to traffic accidents, it is necessary to develop user interfaces for ACC systems that can reduce mode confusion. To meet this requirement, this paper presents a new human-automation interaction design methodology in which the compatibility of the machine and interface models is determined using the proposed criteria, and if the models are incompatible, one or both of the models is/are modified to make them compatible. To investigate the effectiveness of our methodology, we designed two new interfaces by separately modifying the machine model and the interface model and then performed driver-in-the-loop experiments. The results showed that modifying the machine model provides a more compact, acceptable, effective, and safe interface than modifying the interface model. PMID:26076406

  11. Human-Automation Interaction Design for Adaptive Cruise Control Systems of Ground Vehicles

    PubMed Central

    Eom, Hwisoo; Lee, Sang Hun

    2015-01-01

    A majority of recently developed advanced vehicles have been equipped with various automated driver assistance systems, such as adaptive cruise control (ACC) and lane keeping assistance systems. ACC systems have several operational modes, and drivers can be unaware of the mode in which they are operating. Because mode confusion is a significant human error factor that contributes to traffic accidents, it is necessary to develop user interfaces for ACC systems that can reduce mode confusion. To meet this requirement, this paper presents a new human-automation interaction design methodology in which the compatibility of the machine and interface models is determined using the proposed criteria, and if the models are incompatible, one or both of the models is/are modified to make them compatible. To investigate the effectiveness of our methodology, we designed two new interfaces by separately modifying the machine model and the interface model and then performed driver-in-the-loop experiments. The results showed that modifying the machine model provides a more compact, acceptable, effective, and safe interface than modifying the interface model. PMID:26076406

  12. Control of impact crater fracture systems on subsurface hydrology, ground subsidence, and collapse, Mars

    USGS Publications Warehouse

    Rodriguez, J.A.P.; Sasaki, S.; Dohm, J.M.; Tanaka, K.L.; Strom, B.; Kargel, J.; Kuzmin, R.; Miyamoto, H.; Spray, J.G.; Fairen, A.G.; Komatsu, G.; Kurita, K.; Baker, V.

    2005-01-01

    Noachian layered materials are pervasively exposed throughout the highlands of Mars. The layered deposits, in places many kilometers thick, exhibit impact craters of diverse morphologic characteristics, ranging from highly degraded to pristine, most of which formed during the period of heavy bombardment. In addition, exhumed impact craters, ancient channels, and fluvial and alluvial fans are visible in the layered deposits through MOC imagery. These features are more abundant in Noachian terrains, which indicates relatively high erosion rates during ancient Mars that competed with heavy meteoritic bombardment. The Noachian layered materials are thus expected to contain numerous buried impact craters in various states of preservation. Here, we propose that impact craters (buried and exposed) and associated fracture systems dominate the basement structural fabric of the ancient highlands and that they have significantly influenced the hydrogeology. Diversity in the occurrence of high and low densities of impact craters and associated fracture systems controls the magnitude of the local effects of magmatic-driven hydrothermal activity. In and surrounding the Tharsis region, for example, the formation of chaotic terrains (the source regions of the circum-Chryse outflow channel system) and a large diversity of collapse structures, including impact crater moats and pit chains, appear to be the result of enhanced hydrothermal activity. Copyright 2005 by the American Geophysical Union.

  13. Collaborative air/ground command and control for responsive persistent ISR operations using unmanned systems

    NASA Astrophysics Data System (ADS)

    Ordower, Rick; Dixon, Lee; Lynch, Nick

    2010-04-01

    "The foundation for integrating ISR planning and direction is the information network, including the appropriate ISR services and applications oriented toward the [commanders] needs. By combining global visibility of available information and intelligence needs with the tools to maximize platform/sensor/target management, the network will improve efficiency and maximize persistence. Inherent within this concept is the idea of integrating and synchronizing a mix of sensing systems and platforms rather than relying on a single system. The second concept embedded within this concept is the ability to capture the activity/information as it occurs rather than forensically reconstructing after the fact. This requires the ability for the [commander] to adjust collection priorities of the entire collection suite to a level appropriate to the activity of interest. Individual sensors, platforms and exploitation nodes will become more efficient as part of an integrated system. Implementing this fully integrated ISR Enterprise will result in improved persistence, and ultimately better ISR for the warfighter."[3] Over the last 6 years, SAIC has been working with CERDEC and AMRDEC to introduce Battle Command aids supporting (semi) autonomous execution and collaboration of unmanned assets. This paper presents an operational context and a distributed command and control architecture aiming to reduce workload and increase Persistent ISR effectiveness. This architecture has been implemented and demonstrated in field tests and as part of FY'09 C4ISR OTM testbed.

  14. Controls on ground-water chemistry in the Horse Heaven Hills, south-central Washington

    USGS Publications Warehouse

    Steinkampf, W.C.; Bortleson, Gilbert C.; Packard, F.A.

    1985-01-01

    Miocene basaltic aquifers are the source of domestic and municipal water, and about 20,000 acre-feet of irrigation water annually, in the Horse Heaven Hills in south-central Washington State. Groundwater chemical variations derive from the hydraulic characteristics is of the geohydrologic system, from groundwater basalt reactions, and from irrigation. Some dissolved species concentrations increase with residence time; others decrease. Recharge area groundwaters are calcium magnesium sodium bicarbonate waters with sodium-adsorption ratios (SAR's) less than 1.0. They evolve to sodium potassium bicarbonate waters with SAR 's as high as 17. Glassy and cryptocrystalline phases of the basalt are the main sources of dissolved sodium. They dissolve by silicate hydrolysis in carbon dioxide charged waters that recharge the aquifer system. Dissolved silicon, iron, and aluminum concentrations are controlled by the solubilities of amorphous secondary alteration products, which order to silica phases, oxyhydroxides, and smectite. Carbonate mineral precipitation is induced by increasing pH from the hydrolysis reaction. Sodium and potassium concentrations increase until clinoptilolite saturation is reached and precipitation begins. Deviations from the general variation patterns are due to localized geologic structures which distort the groundwater flow system, and to the irrigation use of Columbia River water. (USGS)

  15. An Ecological Approach to the Design of UAV Ground Control Station (GCS) Status Displays

    NASA Technical Reports Server (NTRS)

    Dowell, Susan; Morphew, Ephimia; Shively, Jay

    2003-01-01

    Use of UAVs in military and commercial applications will continue to increase. However, there has been limited research devoted to UAV GCS design. The current study employed an ecological approach to interfac e design. Ecological Interface Design (EID) can be characterized as r epresenting the properties of a system, such that an operator is enco uraged to use skill-based behavior when problem solving. When more ef fortful cognitive processes become necessary due to unfamiliar situations, the application of EID philosophy supports the application of kn owledge-based behavior. With advances toward multiple UAV command and control, operators need GCS interfaces designed to support understan ding of complex systems. We hypothesized that use of EID principles f or the display of UAV status information would result in better opera tor performance and situational awareness, while decreasing workload. Pilots flew a series of missions with three UAV GCS displays of statu s information (Alphanumeric, Ecological, and Hybrid display format). Measures of task performance, Situational Awareness, and workload dem onstrated the benefits of using an ecological approach to designing U AV GCS displays. The application of ecological principles to the design of UAV GCSs is a promising area for improving UAV operations.

  16. Below- and above-ground controls on tree water use in lowland tropical forests

    NASA Astrophysics Data System (ADS)

    Meinzer, F. C.; Woodruff, D.; McCulloh, K.; Domec, J.

    2012-12-01

    scaled uniformly with branch leaf-specific conductivity and with the branch leaf area to sapwood area ratio; a tree architecture-based proxy for leaf-specific conductivity. At the canopy-atmosphere interface, a combination of high stomatal conductance and relatively large leaf size enhanced the role of the boundary layer over stomata in controlling transpiration (increased decoupling coefficient; omega). Uniform scaling of tree water use characteristics with simple biophysical, hydraulic and architectural traits across species may facilitate predictions of changes in tropical forest water use with shifts in species composition associated with climate change and changing land-use.

  17. Practical Applications of Cosmic Ray Science: Spacecraft, Aircraft, Ground-Based Computation and Control Systems, and Human Health and Safety

    NASA Technical Reports Server (NTRS)

    Atwell, William; Koontz, Steve; Normand, Eugene

    2012-01-01

    Three twentieth century technological developments, 1) high altitude commercial and military aircraft; 2) manned and unmanned spacecraft; and 3) increasingly complex and sensitive solid state micro-electronics systems, have driven an ongoing evolution of basic cosmic ray science into a set of practical engineering tools needed to design, test, and verify the safety and reliability of modern complex technological systems. The effects of primary cosmic ray particles and secondary particle showers produced by nuclear reactions with the atmosphere, can determine the design and verification processes (as well as the total dollar cost) for manned and unmanned spacecraft avionics systems. Similar considerations apply to commercial and military aircraft operating at high latitudes and altitudes near the atmospheric Pfotzer maximum. Even ground based computational and controls systems can be negatively affected by secondary particle showers at the Earth s surface, especially if the net target area of the sensitive electronic system components is large. Finally, accumulation of both primary cosmic ray and secondary cosmic ray induced particle shower radiation dose is an important health and safety consideration for commercial or military air crews operating at high altitude/latitude and is also one of the most important factors presently limiting manned space flight operations beyond low-Earth orbit (LEO). In this paper we review the discovery of cosmic ray effects on the performance and reliability of microelectronic systems as well as human health and the development of the engineering and health science tools used to evaluate and mitigate cosmic ray effects in ground-based atmospheric flight, and space flight environments. Ground test methods applied to microelectronic components and systems are used in combinations with radiation transport and reaction codes to predict the performance of microelectronic systems in their operating environments. Similar radiation transport

  18. Structural controls on ground-water conditions and estimated aquifer properties near Bill Williams Mountain, Williams, Arizona

    USGS Publications Warehouse

    Pierce, Herbert A.

    2001-01-01

    As of 1999, surface water collected and stored in reservoirs is the sole source of municipal water for the city of Williams. During 1996 and 1999, reservoirs reached historically low levels. Understanding the ground-water flow system is critical to managing the ground-water resources in this part of the Coconino Plateau. The nearly 1,000-meter-deep regional aquifer in the Redwall and Muav Limestones, however, makes studying or utilizing the resource difficult. Near-vertical faults and complex geologic structures control the ground-water flow system on the southwest side of the Kaibab Uplift near Williams, Arizona. To address the hydrogeologic complexities in the study area, a suite of techniques, which included aeromagnetic, gravity, square-array resistivity, and audiomagnetotelluric surveys, were applied as part of a regional study near Bill Williams Mountain. Existing well data and interpreted geophysical data were compiled and used to estimate depths to the water table and to prepare a potentiometric map. Geologic characteristics, such as secondary porosity, coefficient of anisotropy, and fracture-strike direction, were calculated at several sites to examine how these characteristics change with depth. The 14-kilometer-wide, seismically active northwestward-trending Cataract Creek and the northeastward-trending Mesa Butte Fault systems intersect near Bill Williams Mountain. Several north-south-trending faults may provide additional block faulting north and west of Bill Williams Mountain. Because of the extensive block faulting and regional folding, the volcanic and sedimentary rocks are tilted toward one or more of these faults. These faults provide near-vertical flow paths to the regional water table. The nearly radial fractures allow water that reaches the regional aquifer to move away from the Bill Williams Mountain area. Depth to the regional aquifer is highly variable and depends on location and local structures. On the basis of interpreted

  19. Screen-aided CO 2 control (SACC): a middle ground between FACE and open-top chambers

    NASA Astrophysics Data System (ADS)

    Leadley, P. W.; Niklaus, P.; Stocker, R.; Körner, Ch.

    We have developed a novel CO 2 exposure system for natural vegetation that is a middle ground between Free Air CO 2 Enrichment (FACE) and traditional open-top chambers (OTC). Screen-Aided CO 2 Control (SACC) technology uses much less CO 2 per experiment and per replicate than FACE and is superior to OTCs in terms of its effects on microclimate. A SACC unit consists of a thin metal frame, a clear plastic "screen", and a pipe at the base of the screen through which CO 2 enriched jets of air are directed into the unit. There is a gap between the ground and the bottom of the pipe and the screen is relatively short in comparison to the maximum height of the vegetation. Our SACC units are hexagonal and enclose a ground area of 1.27 m 2. SACC works in the following way: 1) the screen breaks the wind and creates turbulent mixing within the unit, 2) the mixing of the outside air with the CO 2 enriched jets of air generates relatively uniform CO 2 concentrations within the screened-in vegetation, and 3) a fully automated system monitors CO 2 concentrations and adjusts CO 2 injection rates for each unit every ca. 10 minutes to maintain preset CO 2 concentrations. Twenty-four hour means of CO 2 concentrations in the middle of a unit are typically maintained within 1 μl l -1 of their set points. Spatial variation and short-term fluctuations in CO 2 concentration are similar to those in OTCs and FACE. CO 2 consumption at our site is 5 kg CO 2 day -1 replicate -1 for a total of ca. 30 tons per year for 20 elevated CO 2 SACC units. Compared to OTCs, SACC units have reduced temperature peaks at full sunlight, minimal effects on solar radiation, reduced rainfall interception by chamber walls, and freer access of small animals to experimental plots. We believe that SACC is the best method for exposing short stature vegetation to elevated CO 2 when financial constraints do not allow for a properly replicated FACE experiment.

  20. Practical Applications of Cosmic Ray Science: Spacecraft, Aircraft, Ground Based Computation and Control Systems and Human Health and Safety

    NASA Technical Reports Server (NTRS)

    Atwell, William; Koontz, Steve; Normand, Eugene

    2012-01-01

    In this paper we review the discovery of cosmic ray effects on the performance and reliability of microelectronic systems as well as on human health and safety, as well as the development of the engineering and health science tools used to evaluate and mitigate cosmic ray effects in earth surface, atmospheric flight, and space flight environments. Three twentieth century technological developments, 1) high altitude commercial and military aircraft; 2) manned and unmanned spacecraft; and 3) increasingly complex and sensitive solid state micro-electronics systems, have driven an ongoing evolution of basic cosmic ray science into a set of practical engineering tools (e.g. ground based test methods as well as high energy particle transport and reaction codes) needed to design, test, and verify the safety and reliability of modern complex electronic systems as well as effects on human health and safety. The effects of primary cosmic ray particles, and secondary particle showers produced by nuclear reactions with spacecraft materials, can determine the design and verification processes (as well as the total dollar cost) for manned and unmanned spacecraft avionics systems. Similar considerations apply to commercial and military aircraft operating at high latitudes and altitudes near the atmospheric Pfotzer maximum. Even ground based computational and controls systems can be negatively affected by secondary particle showers at the Earth's surface, especially if the net target area of the sensitive electronic system components is large. Accumulation of both primary cosmic ray and secondary cosmic ray induced particle shower radiation dose is an important health and safety consideration for commercial or military air crews operating at high altitude/latitude and is also one of the most important factors presently limiting manned space flight operations beyond low-Earth orbit (LEO).

  1. Efficacy of Insecticide and Bioinsecticide Ground Sprays to Control Metisa plana Walker (Lepidoptera: Psychidae) in Oil Palm Plantations, Malaysia

    PubMed Central

    Salim, Hasber; Rawi, Che Salmah Md.; Ahmad, Abu Hassan; Al-Shami, Salman Abdo

    2015-01-01

    The effectiveness of the synthetic insecticides trichlorfon, lambda-cyhalothrin, cypermethrin emulsion concentrated (EC) and cypermethrin emulsion water based (EW) and a bio-insecticide, Bacillus thuringiensis subsp. kurstaki (Btk), was evaluated at 3, 7, 14 and 30 days after treatment (DAT) for the control of Metisa plana larvae in an oil palm (Elaeis guineensis) plantation in Malaysia. Although all synthetic insecticides effectively reduced the larval population of M. plana, trichlorfon, lambda-cyhalothrin and cypermethrin EC were the fastest-acting. The larval population dropped below the economic threshold level (ETL) 30 days after a single application of the synthetic insecticides. Application of Btk, however, gave poor results, with the larval population remaining above the ETL post treatment. In terms of operational productivity, ground spraying using power spray equipment was time-consuming and resulted in poor coverage. Power spraying may not be appropriate for controlling M. plana infestations in large fields. Using a power sprayer, one man could cover 2–3 ha per day. Hence, power spraying is recommended during outbreaks of infestation in areas smaller than 50 ha. PMID:26868711

  2. Efficacy of Insecticide and Bioinsecticide Ground Sprays to Control Metisa plana Walker (Lepidoptera: Psychidae) in Oil Palm Plantations, Malaysia.

    PubMed

    Salim, Hasber; Rawi, Che Salmah Md; Ahmad, Abu Hassan; Al-Shami, Salman Abdo

    2015-12-01

    The effectiveness of the synthetic insecticides trichlorfon, lambda-cyhalothrin, cypermethrin emulsion concentrated (EC) and cypermethrin emulsion water based (EW) and a bio-insecticide, Bacillus thuringiensis subsp. kurstaki (Btk), was evaluated at 3, 7, 14 and 30 days after treatment (DAT) for the control of Metisa plana larvae in an oil palm (Elaeis guineensis) plantation in Malaysia. Although all synthetic insecticides effectively reduced the larval population of M. plana, trichlorfon, lambda-cyhalothrin and cypermethrin EC were the fastest-acting. The larval population dropped below the economic threshold level (ETL) 30 days after a single application of the synthetic insecticides. Application of Btk, however, gave poor results, with the larval population remaining above the ETL post treatment. In terms of operational productivity, ground spraying using power spray equipment was time-consuming and resulted in poor coverage. Power spraying may not be appropriate for controlling M. plana infestations in large fields. Using a power sprayer, one man could cover 2-3 ha per day. Hence, power spraying is recommended during outbreaks of infestation in areas smaller than 50 ha. PMID:26868711

  3. Piloted simulation of an air-ground profile negotiation process in a time-based Air Traffic Control environment

    NASA Technical Reports Server (NTRS)

    Williams, David H.; Green, Steven M.

    1993-01-01

    Historically, development of airborne flight management systems (FMS) and ground-based air traffic control (ATC) systems has tended to focus on different objectives with little consideration for operational integration. A joint program, between NASA's Ames Research Center (Ames) and Langley Research Center (Langley), is underway to investigate the issues of, and develop systems for, the integration of ATC and airborne automation systems. A simulation study was conducted to evaluate a profile negotiation process (PNP) between the Center/TRACON Automation System (CTAS) and an aircraft equipped with a four-dimensional flight management system (4D FMS). Prototype procedures were developed to support the functional implementation of this process. The PNP was designed to provide an arrival trajectory solution which satisfies the separation requirements of ATC while remaining as close as possible to the aircraft's preferred trajectory. Results from the experiment indicate the potential for successful incorporation of aircraft-preferred arrival trajectories in the CTAS automation environment. Fuel savings on the order of 2 percent to 8 percent, compared to fuel required for the baseline CTAS arrival speed strategy, were achieved in the test scenarios. The data link procedures and clearances developed for this experiment, while providing the necessary functionality, were found to be operationally unacceptable to the pilots. In particular, additional pilot control and understanding of the proposed aircraft-preferred trajectory, and a simplified clearance procedure were cited as necessary for operational implementation of the concept.

  4. Correlation of the Hubble Space Telescope (HST) Space Telescope Imaging Spectrometer (STIS) On-Orbit Data with Pre-launch Predictions and Ground Contamination Controls

    NASA Technical Reports Server (NTRS)

    Hansen, Patricia A.

    2003-01-01

    The Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) was deployed on-orbit in February 1997. The contamination program for STIS was stringently controlled as the five-year end-of-life deposition was set at 158, per optical element. Contamination was controlled through materials selection, extensive vacuum outgassing certifications, cleaning techniques, and environmental controls. In addition to ground contamination controls, on-orbit contamination controls were implemented for both the HST servicing mission activities and early post-servicing mission checkout. The extensive contamination control program will be discussed and the STIS on-orbit data will be correlated with the prelaunch analytical predictions.

  5. Post-Stroke Walking Behaviors Consistent with Altered Ground Reaction Force Direction Control Advise New Approaches to Research and Therapy.

    PubMed

    Boehm, Wendy L; Gruben, Kreg G

    2016-02-01

    Recovery of walking after stroke requires an understanding of how motor control deficits lead to gait impairment. Traditional therapy focuses on removing specific observable gait behaviors that deviate from unimpaired walking; however, those behaviors may be effective compensations for underlying problematic motor control deficits rather than direct effects of the stroke. Neurological deficits caused by stroke are not well understood, and thus, efficient interventions for gait rehabilitation likely remain unrealized. Our laboratory has previously characterized a post-stroke control deficit that yields a specific difference in direction of the ground reaction force (F, limb endpoint force) exerted with the hemiplegic limb of study participants pushing on both stationary and moving pedals while seated. That task was not dependent on F to retain upright posture, and thus, the task did not constrain F direction. Rather, the F direction was the product of neural preference. It is not known if this specific muscle coordination deficit causes the observed walking deviations, but if present during walking, the deficit would prevent upright posture unless counteracted by compensatory behaviors. Compensations are presented that mechanically counteract the F misdirection to allow upright posture. Those compensations are similar to behaviors observed in stroke patients. Based on that alignment between predictions of this theory and clinical observations, we theorize that post-stroke gait results from the attempt to compensate for the underlying F misdirection deficit. Limb endpoint force direction has been shown to be trainable in the paretic upper limb, making it a feasible goal in the lower limb. If this F misdirection theory is valid, these ideas have tremendous promise for advancing the field of post-stroke gait rehabilitation. PMID:26639659

  6. Detection of conduit-controlled ground-water flow in northwestern Puerto Rico using aerial photograph interpretation and geophysical methods

    USGS Publications Warehouse

    Rodríguez-Martínez, Jesús; Richards, Ronald T.

    2000-01-01

    The development potential of ground-water resources in the karst limestone of northwestern Puerto Rico, in an area extending from the Río Camuy to Aguadilla, is uncertain as a result of limited knowledge of the location of areas where a high density of cavities (interconnected fractures, conduits, and other dissolution features) might suggest the occurrence of high water yields. The presence in northwestern Puerto Rico of numerous coastal submarine springs, cavernous porosity in some of the wells, and rivers with entrenched and underground paths, indicate that it is probable that water-bearing, subterranean interconnected cavities occur in the area between the Río Camuy and Aguadilla. The number of exploratory wells needed to determine the location of these conduits or zones of enhanced secondary porosity could be substantially reduced if more information were available about the location of these subterranean features, greatly reducing the drilling costs associated with a trial-and-error exploratory process. A 3-year study was conducted by the U.S. Geological Survey, in cooperation with the Puerto Rico Aqueduct and Sewer Authority, to detect the presence of cavities that might suggest the occurrence of conduit-controlled groundwater flow. Aerial photographs, geologic and topographic maps, and field reconnaissance were used to identify such linear terrain features as ridges, entrenched canyons, and fracture traces. Natural potential and gravity geophysical methods were also used. The following sites were selected for the aerial photograph interpretation and geophysical testing: Caimital Bajo uplands and former Ramey Air Force Base in Aguadilla; Quebrada de los Cedros between Aguadilla and Isabela; the University of Puerto Rico Agricultural Experiment Station, Otilio dairy farm, and Pozo Brujo in Isabela; the Monte Encantado area in Moca and Isabela; and the Rio Camuy cave system in Hatillo and Camuy. In general, the degree of success varied with site and the

  7. Quality-control results for ground-water and surface-water data, Sacramento River Basin, California, National Water-Quality Assessment, 1996-1998

    USGS Publications Warehouse

    Munday, Cathy; Domagalski, Joseph L.

    2003-01-01

    Evaluating the extent that bias and variability affect the interpretation of ground- and surface-water data is necessary to meet the objectives of the National Water-Quality Assessment (NAWQA) Program. Quality-control samples used to evaluate the bias and variability include annual equipment blanks, field blanks, field matrix spikes, surrogates, and replicates. This report contains quality-control results for the constituents critical to the ground- and surface-water components of the Sacramento River Basin study unit of the NAWQA Program. A critical constituent is one that was detected frequently (more than 50 percent of the time in blank samples), was detected at amounts exceeding water-quality standards or goals, or was important for the interpretation of water-quality data. Quality-control samples were collected along with ground- and surface-water samples during the high intensity phase (cycle 1) of the Sacramento River Basin NAWQA beginning early in 1996 and ending in 1998. Ground-water field blanks indicated contamination of varying levels of significance when compared with concentrations detected in environmental ground-water samples for ammonia, dissolved organic carbon, aluminum, and copper. Concentrations of aluminum in surface-water field blanks were significant when compared with environmental samples. Field blank samples collected for pesticide and volatile organic compound analyses revealed no contamination in either ground- or surface-water samples that would effect the interpretation of environmental data, with the possible exception of the volatile organic compound trichloromethane (chloroform) in ground water. Replicate samples for ground water and surface water indicate that variability resulting from sample collection, processing, and analysis was generally low. Some of the larger maximum relative percentage differences calculated for replicate samples occurred between samples having lowest absolute concentration differences and(or) values near

  8. The use of virtual ground to control transmembrane voltages and measure bilayer currents in serial arrays of droplet interface bilayers

    NASA Astrophysics Data System (ADS)

    Sarles, Stephen A.

    2013-09-01

    The droplet interface bilayer (DIB) is a simple technique for constructing a stable lipid bilayer at the interface of two lipid-encased water droplets submerged in oil. Networks of DIBs formed by connecting more than two droplets constitute a new form of modular biomolecular smart material, where the transduction properties of a single lipid bilayer can affect the actions performed at other interface bilayers in the network via diffusion through the aqueous environments of shared droplet connections. The passive electrical properties of a lipid bilayer and the arrangement of droplets that determine the paths for transport in the network require specific electrical control to stimulate and interrogate each bilayer. Here, we explore the use of virtual ground for electrodes inserted into specific droplets in the network and employ a multichannel patch clamp amplifier to characterize bilayer formation and ion-channel activity in a serial DIB array. Analysis of serial connections of DIBs is discussed to understand how assigning electrode connections to the measurement device can be used to measure activity across all lipid membranes within a network. Serial arrays of DIBs are assembled using the regulated attachment method within a multi-compartment flexible substrate, and wire-type electrodes inserted into each droplet compartment of the substrate enable the application of voltage and measurement of current in each droplet in the array.

  9. Coordination of muscles to control the footpath during over-ground walking in neurologically intact individuals and stroke survivors.

    PubMed

    Srivastava, Shraddha; Kao, Pei-Chun; Reisman, Darcy S; Higginson, Jill S; Scholz, John P

    2016-07-01

    The central nervous system (CNS) is believed to use the abundant degrees of freedom of muscles and joints to stabilize a particular task variable important for task success, such as footpath during walking. Stroke survivors often demonstrate impaired balance and high incidences of falls due to increased footpath variability during walking. In the current study, we use the uncontrolled manifold (UCM) approach to investigate the role of motor abundance in stabilizing footpath during swing phase in healthy individuals and stroke survivors. Twelve stroke survivors and their age- and gender-matched controls walked over-ground at self-selected speed, while electromyographic and kinematic data were collected. UCM analysis partitioned the variance of muscle groups (modes) across gait cycles into "good variance" (i.e., muscle mode variance leading to a consistent or stable footpath) or "bad variance" (i.e., muscle mode variance resulting in an inconsistent footpath). Both groups had a significantly greater "good" than "bad" variance, suggesting that footpath is an important task variable stabilized by the CNS during walking. The relative variance difference that reflects normalized difference between "good" and "bad" variance was not significantly different between groups. However, significant differences in muscle mode structure and muscle mode activation timing were observed between the two groups. Our results suggest that though the mode structure and activation timing are altered, stroke survivors may retain their ability to explore the redundancy within the neuromotor system and utilize it to stabilize the footpath. PMID:26898314

  10. Long-term sequential monitoring of controlled graves representing common burial scenarios with ground penetrating radar: Years 2 and 3

    NASA Astrophysics Data System (ADS)

    Schultz, John J.; Walter, Brittany S.; Healy, Carrie

    2016-09-01

    Geophysical techniques such as ground-penetrating radar (GPR) have been successfully used for forensic searches to locate clandestine graves and physical evidence. However, additional controlled research is needed to fully understand the applicability of this technology when searching for clandestine graves in various environments, soil types, and for longer periods of time post-burial. The purpose of this study was to determine the applicability of GPR for detecting controlled graves in a Spodosol representing multiple burial scenarios for Years 2 and 3 of a three-year monitoring period. Objectives included determining how different burial scenarios are factors in producing a distinctive anomalous response; determining how different GPR imagery options (2D reflection profiles and horizontal time slices) can provide increased visibility of the burials; and comparing GPR imagery between 500 MHz and 250 MHz dominant frequency antennae. The research site contained a grid with eight graves representing common forensic burial scenarios in a Spodosol, a common soil type of Florida, with six graves containing a pig carcass (Sus scrofa). Burial scenarios with grave items (a deep grave with a layer of rocks over the carcass and a carcass wrapped in a tarpaulin) produced a more distinctive response with clearer target reflections over the duration of the monitoring period compared to naked carcasses. Months with increased precipitation were also found to produce clearer target reflections than drier months, particularly during Year 3 when many grave scenarios that were not previously visible became visible after increased seasonal rainfall. Overall, the 250 MHz dominant frequency antenna imagery was more favorable than the 500 MHz. While detection of a simulated grave may be difficult to detect over time, long term detection of a grave in a Spodosol may be possible if the disturbed spodic horizon is detected. Furthermore, while grave visibility increased with the 2D

  11. International Space Station Sustaining Engineering: A Ground-Based Test Bed for Evaluating Integrated Environmental Control and Life Support System and Internal Thermal Control System Flight Performance

    NASA Technical Reports Server (NTRS)

    Ray, Charles D.; Perry, Jay L.; Callahan, David M.

    2000-01-01

    As the International Space Station's (ISS) various habitable modules are placed in service on orbit, the need to provide for sustaining engineering becomes increasingly important to ensure the proper function of critical onboard systems. Chief among these are the Environmental Control and Life Support System (ECLSS) and the Internal Thermal Control System (ITCS). Without either, life onboard the ISS would prove difficult or nearly impossible. For this reason, a ground-based ECLSS/ITCS hardware performance simulation capability has been developed at NASA's Marshall Space Flight Center. The ECLSS/ITCS Sustaining Engineering Test Bed will be used to assist the ISS Program in resolving hardware anomalies and performing periodic performance assessments. The ISS flight configuration being simulated by the test bed is described as well as ongoing activities related to its preparation for supporting ISS Mission 5A. Growth options for the test facility are presented whereby the current facility may be upgraded to enhance its capability for supporting future station operation well beyond Mission 5A. Test bed capabilities for demonstrating technology improvements of ECLSS hardware are also described.

  12. Questa baseline and pre-mining ground-water-quality investigation. 16. Quality assurance and quality control for water analyses

    USGS Publications Warehouse

    McCleskey, R. Blaine; Nordstrom, D. Kirk; Naus, Cheryl A.

    2004-01-01

    The Questa baseline and pre-mining ground-water quality investigation has the main objective of inferring the ground-water chemistry at an active mine site. Hence, existing ground-water chemistry and its quality assurance and quality control is of crucial importance to this study and a substantial effort was spent on this activity. Analyses of seventy-two blanks demonstrated that contamination from processing, handling, and analyses were minimal. Blanks collected using water deionized with anion and cation exchange resins contained elevated concentrations of boron (0.17 milligrams per liter (mg/L)) and silica (3.90 mg/L), whereas double-distilled water did not. Boron and silica were not completely retained by the resins because they can exist as uncharged species in water. Chloride was detected in ten blanks, the highest being 3.9 mg/L, probably as the result of washing bottles, filter apparatuses, and tubing with hydrochloric acid. Sulfate was detected in seven blanks; the highest value was 3.0 mg/L, most likely because of carryover from the high sulfate waters sampled. With only a few exceptions, the remaining blank analyses were near or below method detection limits. Analyses of standard reference water samples by cold-vapor atomic fluorescence spectrometry, ion chromatography, inductively coupled plasma-optical emission spectrometry, inductively coupled plasma-mass spectrometry, FerroZine, graphite furnace atomic absorption spectrometry, hydride generation atomic spectrometry, and titration provided an accuracy check. For constituents greater than 10 times the detection limit, 95 percent of the samples had a percent error of less than 8.5. For constituents within 10 percent of the detection limit, the percent error often increased as a result of measurement imprecision. Charge imbalance was calculated using WATEQ4F and 251 out of 257 samples had a charge imbalance less than 11.8 percent. The charge imbalance for all samples ranged from -16 to 16 percent. Spike

  13. Control of strong ground motion of mining-induced earthquakes by the strength of the seismogenic rock mass

    USGS Publications Warehouse

    McGarr, A.

    2002-01-01

    The shear stress ?? that can be sustained by the rock mass in the environs of a mining-induced earthquake controls the near-fault peak ground velocity v of that event according to v???0.25(??/G) ??, where ?? is the shear wave speed and G is the modulus of rigidity. To estimate ?? at mining depths, I review the results of four studies involving Witwatersrand tremors that relate to the bulk shear strength. The first and most general analysis uses the common assumptions that the seismogenic crust is pervasively faulted, has hydrostatic pore pressure before mining, and an extensional stress state that is close to failure. Mining operations reduce the pore pressure to zero within the mine and redistribute the stresses such that, in localized regions, the state of stress is again at the point of failure. Laboratory friction experiments can be used to estimate ?? in the zero-pore-pressure regime. Second, model calculations of states of stress in the vicinity of milling at about 3 km depth indicated the shear stress available to cause faulting near the centre of a distribution of induced earthquakes. Third, laboratory experiments combined with microscopic analyses of fault gouge from the rupture zone of a mining-induced event provided an estimate of the average shear stress acting on the fault to cause this earthquake at a depth of 2 km. Fourth, moment tensors determined for mining- induced earthquakes usually show substantial implosive components, from which it is straightforward to estimate ??. These four different analyses yield estimates of ?? that fall in the range 30 to 61 MPa which implies that near-fault particle velocities could he as high as about 1.5 m/s. To the extent that the causative fault ruptures previously intact rock, both ?? and v, in localized regions, could be several times higher than 61 MPa and 1.5 m/s.

  14. Direct Georeferencing on Small Unmanned Aerial Platforms for Improved Reliability and Accuracy of Mapping Without the Need for Ground Control Points

    NASA Astrophysics Data System (ADS)

    Mian, O.; Lutes, J.; Lipa, G.; Hutton, J. J.; Gavelle, E.; Borghini, S.

    2015-08-01

    This paper presents results from a Direct Mapping Solution (DMS) comprised of an Applanix APX-15 UAV GNSS-Inertial system integrated with a Sony a7R camera to produce highly accurate ortho-rectified imagery without Ground Control Points on a Microdrones md4-1000 platform. A 55 millimeter Nikkor f/1.8 lens was mounted on the Sony a7R and the camera was then focused and calibrated terrestrially using the Applanix camera calibration facility, and then integrated with the APX-15 UAV GNSS-Inertial system using a custom mount specifically designed for UAV applications. In July 2015, Applanix and Avyon carried out a test flight of this system. The goal of the test flight was to assess the performance of DMS APX-15 UAV direct georeferencing system on the md4-1000. The area mapped during the test was a 250 x 300 meter block in a rural setting in Ontario, Canada. Several ground control points are distributed within the test area. The test included 8 North-South lines and 1 cross strip flown at 80 meters AGL, resulting in a ~1 centimeter Ground Sample Distance (GSD). Map products were generated from the test flight using Direct Georeferencing, and then compared for accuracy against the known positions of ground control points in the test area. The GNSS-Inertial data collected by the APX-15 UAV was post-processed in Single Base mode, using a base station located in the project area via POSPac UAV. The base-station's position was precisely determined by processing a 12-hour session using the CSRS-PPP Post Processing service. The ground control points were surveyed in using differential GNSS post-processing techniques with respect to the base-station.

  15. Biogeochemical and hydrological processes controlling the transport and fate of 1,2-dibromoethane (EDB) in soil and ground water, central Florida

    USGS Publications Warehouse

    Katz, Brian G.

    1993-01-01

    Widespread contamination of ground water in central Florida by 1,2-dibromoethane (EDB) has resulted because of its heavy usage as a soil fumigant during a 20-year period, its relatively high aqueous solubility, and the low sorption capacity of the highly permeable sandy soils lacking organic matter. Two models were used to improve understanding of biogeochemical and hydrological processes that control the transport and fate of EDB in soil and ground water. First, a mass-balance model was developed to estimate the max-imum concentration of EDB in ground water resulting from known application rates of EDB. Key processes that were quantified in the model included volatilization, diffusion of EDB vapor in soils, partitioning between aqueous and gaseous phases, sorption of EDB vapor on organic carbon and soil particles, chemical and biological degradation reactions, and nonreversible binding of EDB to soils. Model calculations using an EDB half-life of 0.65 year closely reproduced the maximum observed concentrations in ground water, 37 and 0.22 micrograms per liter, at downgradient sites in two study areas in central Florida. Maximum concentrations of EDB in ground water also were estimated in a second model that incorporated an analytical solution to the three-dimensional advection-dispersion equation for instantaneous point sources of EDB entering the flow systems in the two study areas. The model used an EDB half-life of 0.65 year (obtained from the mass-balance calculations), mean ground-water flow velocities of 0.6 to 1 meter per day, coefficients of longitudinal hydro-dynamic dispersion of 0.6 to 1.0 square meter per day, and coefficients of transverse hydrodynamic dispersion of 0.1 square meter per day. Peak concentrations of EDB in ground water calculated from the analytical model agreed closely with observed peak concentrations measured from 1983 through 1987.

  16. Ground Operations

    NASA Technical Reports Server (NTRS)

    Eastman, Randy

    2000-01-01

    The contents include: 1) Integrated Space Transportation; 2) Fourth Generation Reusable Launch Vehicle (RLV) Research; 3) Ground Operations; 4) Ground Operations Technologies; 5) Sensors; and 6) Umbilicals. This paper is presented in viewgraph form.

  17. Examination about Influence for Precision of 3d Image Measurement from the Ground Control Point Measurement and Surface Matching

    NASA Astrophysics Data System (ADS)

    Anai, T.; Kochi, N.; Yamada, M.; Sasaki, T.; Otani, H.; Sasaki, D.; Nishimura, S.; Kimoto, K.; Yasui, N.

    2015-05-01

    As the 3D image measurement software is now widely used with the recent development of computer-vision technology, the 3D measurement from the image is now has acquired the application field from desktop objects as wide as the topography survey in large geographical areas. Especially, the orientation, which used to be a complicated process in the heretofore image measurement, can be now performed automatically by simply taking many pictures around the object. And in the case of fully textured object, the 3D measurement of surface features is now done all automatically from the orientated images, and greatly facilitated the acquisition of the dense 3D point cloud from images with high precision. With all this development in the background, in the case of small and the middle size objects, we are now furnishing the all-around 3D measurement by a single digital camera sold on the market. And we have also developed the technology of the topographical measurement with the air-borne images taken by a small UAV [1~5]. In this present study, in the case of the small size objects, we examine the accuracy of surface measurement (Matching) by the data of the experiments. And as to the topographic measurement, we examine the influence of GCP distribution on the accuracy by the data of the experiments. Besides, we examined the difference of the analytical results in each of the 3D image measurement software. This document reviews the processing flow of orientation and the 3D measurement of each software and explains the feature of the each software. And as to the verification of the precision of stereo-matching, we measured the test plane and the test sphere of the known form and assessed the result. As to the topography measurement, we used the air-borne image data photographed at the test field in Yadorigi of Matsuda City, Kanagawa Prefecture JAPAN. We have constructed Ground Control Point which measured by RTK-GPS and Total Station. And we show the results of analysis made

  18. Control of Clostridium perfringens Spores by Green Tea Leaf Extracts During Cooling of Cooked Ground Beef, Chicken, and Pork

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated the inhibition of Clostridium perfringens spore germination and outgrowth by two green tea extracts with low (GTL; 141 mg total catechins/g of green tea extract) and high (GTE; 697 mg total catechins/g of extract) catechin levels during abusive chilling of retail cooked ground beef, ...

  19. Non-equilibrium pressure control of the height of a large-scale, ground-coupled, rotating fluid column

    NASA Astrophysics Data System (ADS)

    Ash, R. L.; Zardadkhan, I. R.

    2013-05-01

    When a ground-coupled, rotating fluid column is modeled incorporating non-equilibrium pressure forces in the Navier-Stokes equations, a new exact solution results. The solution has been obtained in a similar manner to the classical equilibrium solution. Unlike the infinite-height, classical solution, the non-equilibrium pressure solution yields a ground-coupled rotating fluid column of finite height. A viscous, non-equilibrium Rankine vortex velocity distribution, developed previously, was used to demonstrate how the viscous and non-equilibrium pressure gradient forces, arising in the vicinity of the velocity gradient discontinuity that is present in the classical Rankine vortex model, effectively isolate the rotating central fluid column from the outer potential vortex region. Thus, the non-equilibrium region acts to confine and shield the central, rigid-body-like, rotating fluid core, justifying this examination of how such a rotating fluid column can interact with the ground. The resulting non-equilibrium ground-coupled, rotating fluid column solution was employed to estimate the central column heights of three well-documented dust devils, and the central column height predictions were consistent with published dust devil height statistics.

  20. Ground-water sampling methods and quality-control data for the Red River of the North basin, Minnesota, North Dakota, and South Dakota, 1993-95

    USGS Publications Warehouse

    Menheer, M.A.; Brigham, M.E.

    1997-01-01

    Quality-control data demonstrated that most constituents measured for this study yielded reproducible data, with low to undetectable contamination from the sampling and analytical procedures. Several constituents were occasionally or frequently detected in blank samples at levels similar to low-concentration ground-water-quality samples. For example, iron was detected in 75 percent of the blank samples, with a maximum concentration of 27 [ig/L, indicating that iron contamination may interfere with its determination at low levels in ground waters. Copper, aluminum, and dissolved organic carbon concentrations in blank samples overlap those determined in ground-waterquality samples, thereby precluding quantitative reporting of those constituents. Most pesticide data are reproducible, with minimal bias. Some pesticides had low but consistent recoveries; these data may be useful if spike and surrogate data are carefully considered. Data for some pesticides measured in this study should not be quantitatively reported or used, because they may underestimate the concentrations of those pesticides in ground waters.

  1. LONG-TERM STABILITY OF THE LOCAL GROUND CONTROL NETWORK AT THE CO-LOCATION SITE OF MEDICINA

    NASA Astrophysics Data System (ADS)

    Abbondanza, C.; Sarti, P.; Legrand, J.

    2009-12-01

    ITRF combinations rely on the availability of accurate tie vectors linking reference points of space geodetic techniques. Co-located instruments are assumed to move consistently and no local relative motion is taken into account. Instabilities may degrade the quality of the co-location itself and perturb the result of ITRF combinations. This work aims to determine the stability of the local ground control network at Medicina (Italy) with independent surveying methods. The observatory hosts a co-location between a VLBI telescope and two GPS antennas, MEDI and MSEL. It is located in the Po Plain where thick layers of clays are the prevalent soil characteristics. Hence, provision of long term stability of geodetic monuments is a challenge and monitoring their stability is an issue. MEDI and the VLBI station regularly contribute to the determination of ITRF, while MSEL is part of the EUREF network. A set of five tie vectors observations linking the VLBI and MEDI reference points was acquired between 2001 and 2007. It is our main tool for performing local deformation analysis. Additionally, the GPS time series of MEDI and MSEL were used to cross check and confirm the local instability detected by terrestrial methods. To achieve a rigorous and reliable investigation of the local stability, multi-epoch terrestrial observations were homogeneously processed according to common parameterizations in a consistent reference frame. Similarly, continuous GPS observations from MEDI and MSEL were analysed according to the new EPN reprocessing strategy in order to monitor the short baseline between MEDI and MSEL; to spotlight any change in its length. Both approaches confirm differential motions at the site which can be related to monument instabilities originated by the particularly unfavourable local geological setting and the inapt design of the monuments foundation. The monuments move non homogeneously at rates reaching up to 1.6 mm/year, this value being comparable to intra

  2. Ground-based simulation of telepresence for materials science experiments. [remote viewing and control of processes aboard Space Station

    NASA Technical Reports Server (NTRS)

    Johnston, James C.; Rosenthal, Bruce N.; Bonner, Mary JO; Hahn, Richard C.; Herbach, Bruce

    1989-01-01

    A series of ground-based telepresence experiments have been performed to determine the minimum video frame rate and resolution required for the successive performance of materials science experiments in space. The approach used is to simulate transmission between earth and space station with transmission between laboratories on earth. The experiments include isothermal dendrite growth, physical vapor transport, and glass melting. Modifications of existing apparatus, software developed, and the establishment of an inhouse network are reviewed.

  3. Aquifer-scale controls on the distribution of nitrate and ammonium in ground water near La Pine, Oregon, USA

    USGS Publications Warehouse

    Hinkle, S.R.; Böhlke, J.K.; Duff, J.H.; Morgan, D.S.; Weick, R.J.

    2007-01-01

    Geochemical and isotopic tools were applied at aquifer, transect, and subtransect scales to provide a framework for understanding sources, transport, and fate of dissolved inorganic N in a sandy aquifer near La Pine, Oregon. NO3 is a common contaminant in shallow ground water in this area, whereas high concentrations of NH4-N (up to 39 mg/L) are present in deep ground water. N concentrations, N/Cl ratios, tracer-based apparent ground-water ages, N isotope data, and hydraulic gradients indicate that septic tank effluent is the primary source of NO3. N isotope data, N/Cl and N/C relations, 3H data, and hydraulic considerations point to a natural, sedimentary organic matter source for the high concentrations of NH4, and are inconsistent with an origin as septic tank N. Low recharge rates and flow velocities have largely restricted anthropogenic NO3 to isolated plumes within several meters of the water table. A variety of geochemical and isotopic data indicate that denitrification also affects NO3 gradients in the aquifer. Ground water in the La Pine aquifer evolves from oxic to increasingly reduced conditions. Suboxic conditions are achieved after about 15-30 y of transport below the water table. NO3 is denitrified near the oxic/suboxic boundary. Denitrification in the La Pine aquifer is characterized well at the aquifer scale with a redox boundary approach that inherently captures spatial variability in the distribution of electron donors. ?? 2006 Elsevier B.V. All rights reserved.

  4. Control of the electronic ground state on an electron-transfer copper site by second-sphere perturbations.

    PubMed

    Morgada, Marcos N; Abriata, Luciano A; Zitare, Ulises; Alvarez-Paggi, Damian; Murgida, Daniel H; Vila, Alejandro J

    2014-06-10

    The Cu(A) center is a dinuclear copper site that serves as an optimized hub for long-range electron transfer in heme-copper terminal oxidases. Its electronic structure can be described in terms of a σ(u)* ground-state wavefunction with an alternative, less populated ground state of π(u) symmetry, which is thermally accessible. It is now shown that second-sphere mutations in the Cu(A) containing subunit of Thermus thermophilus ba3 oxidase perturb the electronic structure, which leads to a substantial increase in the population of the π(u) state, as shown by different spectroscopic methods. This perturbation does not affect the redox potential of the metal site, and despite an increase in the reorganization energy, it is not detrimental to the electron-transfer kinetics. The mutations were achieved by replacing the loops that are involved in protein-protein interactions with cytochrome c, suggesting that transient protein binding could also elicit ground-state switching in the oxidase, which enables alternative electron-transfer pathways. PMID:24777732

  5. The U.S. Geological Survey Modular Ground-Water Model - PCGN: A Preconditioned Conjugate Gradient Solver with Improved Nonlinear Control

    USGS Publications Warehouse

    Naff, Richard L.; Banta, Edward R.

    2008-01-01

    The preconditioned conjugate gradient with improved nonlinear control (PCGN) package provides addi-tional means by which the solution of nonlinear ground-water flow problems can be controlled as compared to existing solver packages for MODFLOW. Picard iteration is used to solve nonlinear ground-water flow equations by iteratively solving a linear approximation of the nonlinear equations. The linear solution is provided by means of the preconditioned conjugate gradient algorithm where preconditioning is provided by the modi-fied incomplete Cholesky algorithm. The incomplete Cholesky scheme incorporates two levels of fill, 0 and 1, in which the pivots can be modified so that the row sums of the preconditioning matrix and the original matrix are approximately equal. A relaxation factor is used to implement the modified pivots, which determines the degree of modification allowed. The effects of fill level and degree of pivot modification are briefly explored by means of a synthetic, heterogeneous finite-difference matrix; results are reported in the final section of this report. The preconditioned conjugate gradient method is coupled with Picard iteration so as to efficiently solve the nonlinear equations associated with many ground-water flow problems. The description of this coupling of the linear solver with Picard iteration is a primary concern of this document.

  6. Techniques for enhancing durability and equivalence ratio control in a rich-lean, three-stage ground power gas turbine combustor

    NASA Technical Reports Server (NTRS)

    Schultz, D. F.

    1982-01-01

    Rig tests of a can-type combustor were performed to demonstrate two advanced ground power engine combustor concepts: steam cooled rich-burn combustor primary zones for enhanced durability; and variable combustor geometry for three stage combustion equivalence ratio control. Both concepts proved to be highly successful in achieving their desired objectives. The steam cooling reduced peak liner temperatures to less than 800 K. This offers the potential of both long life and reduced use of strategic materials for liner fabrication. Three degrees of variable geometry were successfully implemented to control airflow distribution within the combustor. One was a variable blade angle axial flow air swirler to control primary airflow while the other two consisted of rotating bands to control secondary and tertiary or dilution air flow.

  7. Effect of ground-grid changes on control-cable voltages at Bruce NGS B. Report No. 90-141-K

    SciTech Connect

    Harvey, S.M.; Dick, E.P.

    1990-01-01

    On August 4th and October 15th, 1989, while thunderstorms were in progress, numerous electrical and instrumentation faults appeared on units 0 and 5 of Bruce Nuclear Generating Station B, resulting in the temporary unavailability of critical standby generators, unwarranted station service transfers, and fuse blowing on DC supply wiring. An investigation appeared to implicate the control and annunciation cables running between the powerhouse and standby generators SG5 and SG6 located between the intake and outflow channels at the south end of the station. It was hypothesized that the installation of additional, appropriately placed, bonding conductors to the station ground mat could alleviate the problem. This report describes some field tests performed to determine the effect of adding additional bonding conductors on the ground potential difference and on the voltages and currents appearing on a selected cable.

  8. A robust nonlinear skid-steering control design applied to the MULE (6x6) unmanned ground vehicle

    NASA Astrophysics Data System (ADS)

    Kaloust, Joseph

    2006-05-01

    The paper presents a robust nonlinear skid-steering control design concept. The control concept is based on the recursive/backstepping control design technique and is capable of compensating for uncertainties associated with sensor noise measurements and/or system dynamic state uncertainties. The objective of this control design is to demonstrate the performance of the nonlinear controller under uncertainty associate with road traction (rough off-road and on-road terrain). The MULE vehicle is used in the simulation modeling and results.

  9. Evaluation of ERTS multispectral signatures in relation to ground control signatures using a nested-sampling approach

    NASA Technical Reports Server (NTRS)

    Lyon, R. J. P. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. Ground measured spectral signatures of wavelength bands matching ERTS MSS were collected using a radiometer at several Californian and Nevadan sites, and directly compared with similar data from ERTS CCTs. The comparison was tested at the highest possible spatial resolution for ERTS, using deconvoluted MSS data, and contrasted with that of ground measured spectra, originally from 1 meter squares. In the mobile traverses of the grassland sites, these one meter fields of view were integrated into eighty meter transects along the five km track across four major rock/soil types. Suitable software was developed to read the MSS CCT tapes, to shadeprint individual bands with user-determined greyscale stretching. Four new algorithms for unsupervised and supervised, normalized and unnormalized clustering were developed, into a program termed STANSORT. Parallel software allowed the field data to be calibrated, and by using concurrently continuously collected, upward- and downward-viewing, 4 band radiometers, bidirectional reflectances could be calculated.

  10. Stochastic modeling and control system designs of the NASA/MSFC Ground Facility for large space structures: The maximum entropy/optimal projection approach

    NASA Technical Reports Server (NTRS)

    Hsia, Wei-Shen

    1986-01-01

    In the Control Systems Division of the Systems Dynamics Laboratory of the NASA/MSFC, a Ground Facility (GF), in which the dynamics and control system concepts being considered for Large Space Structures (LSS) applications can be verified, was designed and built. One of the important aspects of the GF is to design an analytical model which will be as close to experimental data as possible so that a feasible control law can be generated. Using Hyland's Maximum Entropy/Optimal Projection Approach, a procedure was developed in which the maximum entropy principle is used for stochastic modeling and the optimal projection technique is used for a reduced-order dynamic compensator design for a high-order plant.

  11. Observation of an Aligned Gas - Solid "Eutectic" during Controlled Directional Solidification Aboard the International Space Station - Comparison with Ground-based Studies

    NASA Technical Reports Server (NTRS)

    Grugel, R. N.; Anilkumar, A.

    2005-01-01

    Direct observation of the controlled melting and solidification of succinonitrile was conducted in the glovebox facility of the International Space Station (ISS). The experimental samples were prepared on ground by filling glass tubes, 1 cm ID and approximately 30 cm in length, with pure succinonitrile (SCN) in an atmosphere of nitrogen at 450 millibar pressure for eventual processing in the Pore Formation and Mobility Investigation (PFMI) apparatus in the glovebox facility (GBX) on board the ISS. Real time visualization during controlled directional melt back of the sample showed nitrogen bubbles emerging from the interface and moving through the liquid up the imposed temperature gradient. Over a period of time these bubbles disappear by dissolving into the melt. Translation is stopped after melting back of about 9 cm of the sample, with an equilibrium solid-liquid interface established. During controlled re-solidification, aligned tubes of gas were seen growing perpendicular to the planar solid/liquid interface, inferring that the nitrogen previously dissolved into the liquid SCN was now coming out at the solid/liquid interface and forming the little studied liquid = solid + gas eutectic-type reaction. The observed structure is evaluated in terms of spacing dimensions, interface undercooling, and mechanisms for spacing adjustments. Finally, the significance of processing in a microgravity environment is ascertained in view of ground-based results.

  12. Ground effects and control effectiveness tests of a .095 scale powered model of a modified T-39 lift/cruise fan V/STOL research airplane

    NASA Technical Reports Server (NTRS)

    Dawson, C. R.; Omar, E.

    1977-01-01

    Wind tunnel test data are analysed to determine ground effects and the effectiveness of the aerodynamic control surfaces to provide a technology base for a Navy type A V/STOL airplane. Three 14CM (5.5 inch) turbopowered simulators were used to power the model which was tested primarily in the following configurations: (1) VTOL with flaps deployed, gear down, and engines tilted to 80 deg, 90 deg, and 95 deg, (2) STOL with flap and gear down and engines tilted to 50 deg; and (3) Loiter with flaps and gear up and L/C nacelles off. Data acquired during the tests are included as an appendix.

  13. Multispectral signatures in relation to ground control signature using nested sampling approach. [mineral detection in Nevada and California

    NASA Technical Reports Server (NTRS)

    Lyon, R. J. P.; Honey, F. R. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. In a cooperative study with USGS personnel, it has been possible to detect a 1.5 by 1 mile anomaly on ERTS CCT data, in the pine-covered mountains of western Nevada. This anomalous area is about 3-5 times larger than that of the known geobotanical anomaly which lies centrally within the area. The site has been studied on the ground and bi-directional reflectances, relative to BaS04 obtained for 40 trees, using both in-vivo techniques (similar to cherry picker operations) and field determinations of cut branches. The anomaly can be seen best by color transparencies made from 5/4, 6/4, 7/4 ratioed digital data, the 3 ratios each being coded by one of 3 colors (blue, green, and red).

  14. Hardware Development and Locomotion Control Strategy for an Over-Ground Gait Trainer: NaTUre-Gaits

    PubMed Central

    Low, Kin Huat; Qu, Xingda; Lim, Hup Boon; Hoon, Kay Hiang

    2014-01-01

    Therapist-assisted body weight supported (TABWS) gait rehabilitation was introduced two decades ago. The benefit of TABWS in functional recovery of walking in spinal cord injury and stroke patients has been demonstrated and reported. However, shortage of therapists, labor-intensiveness, and short duration of training are some limitations of this approach. To overcome these deficiencies, robotic-assisted gait rehabilitation systems have been suggested. These systems have gained attentions from researchers and clinical practitioner in recent years. To achieve the same objective, an over-ground gait rehabilitation system, NaTUre-gaits, was developed at the Nanyang Technological University. The design was based on a clinical approach to provide four main features, which are pelvic motion, body weight support, over-ground walking experience, and lower limb assistance. These features can be achieved by three main modules of NaTUre-gaits: 1) pelvic assistance mechanism, mobile platform, and robotic orthosis. Predefined gait patterns are required for a robotic assisted system to follow. In this paper, the gait pattern planning for NaTUre-gaits was accomplished by an individual-specific gait pattern prediction model. The model generates gait patterns that resemble natural gait patterns of the targeted subjects. The features of NaTUre-gaits have been demonstrated by walking trials with several subjects. The trials have been evaluated by therapists and doctors. The results show that 10-m walking trial with a reduction in manpower. The task-specific repetitive training approach and natural walking gait patterns were also successfully achieved. PMID:27170876

  15. Behavior of aircraft antiskid breaking systems on dry and wet runway surfaces: A slip-ratio-controlled system with ground speed reference from unbraked nose wheel

    NASA Technical Reports Server (NTRS)

    Tanner, J. A.; Stubbs, S. M.

    1977-01-01

    An experimental investigation was conducted at the Langley aircraft landing loads and traction facility to study the braking and cornering response of a slip ratio controlled aircraft antiskid braking system with ground speed reference derived from an unbraked nose wheel. The investigation, conducted on dry and wet runway surfaces, utilized one main gear wheel, brake, and tire assembly of a DC-9 series 10 airplane. During maximum braking, the average ratio of the drag force friction coefficient developed by the antiskid system to the maximum drag force friction coefficient available was higher on the dry surface than on damp and flooded surfaces, and was reduced with lighter vertical loads, higher yaw angles, and when new tire treads were replaced by worn treads. Similarly, the average ratio of side force friction coefficient developed by the tire under antiskid control to the maximum side force friction coefficient available to a freely rolling yawed tire decreased with increasing yaw angle, generally increased with ground speed, and decreased when tires with new treads were replaced by those with worn treads.

  16. Study of the Reactions Controlling the Mobility of Uranium in Ground and Surface Water Systems in Contact with Apatite

    SciTech Connect

    Taffet, M

    2004-04-22

    The objective of this project was to define the mechanisms, equilibria, kinetics, and extent of sorption of aqueous uranium onto hydroxyapatite (Ca{sub 5}(PO{sub 4}){sub 3}(OH)) for a range of pH, ionic strength, aqueous uranium concentration, dissolved carbon/air CO{sub 2}, and mineral surface area. We conducted chemical modeling, batch and flow-through experiments, chemical analysis, x-ray absorption and diffraction measurement, and electron microscopy. Our motivation was the need to immobilize U in water and soil to prevent it's entry into water supplies and ultimately, biological systems. Applying hydroxyapatite to in-situ treatment of uranium-bearing ground water could be an effective, low cost technology. We found that hydroxyapatite quickly, effectively, and reversibly sorbed uranium at a high capacity by inner-sphere complexation over a wide range of conditions. Our results indicate that at aqueous uranium concentrations below 10-20 ppb: (1) equilibrium sorption of uranium to hydroxyapatite occurs in hours, regardless of pH; (2) in ambient and CO{sub 2}-free atmospheres, over 98% of initial uranium is sorbed to hydroxyapatite, (3) in waters in equilibrium with higher air CO{sub 2} concentrations, sorption removed over 97% of aqueous uranium, except above pH 9, where aqueous uranium concentrations were reduced by less than 40%, and (4) at near-neutral pH, bicarbonate alkalinities in excess of 500 slightly retarded sorption of uranium to hydroxyapatite, relative to lower alkalinities. Uranium sorption and precipitation are reversible and are not appreciably affected by ionic strength. The reversibility of these reactions requires that in situ treatment be carefully monitored to avoid breakthrough and de-sorption of uranium unto ground water. At typical surface conditions, sorption is the only mode of uranium sequestration below 20-50 ppb U - above this range, precipitation of uranium phosphate minerals begins to dominate sequestration processes. We verified

  17. Ground State Spin Logic

    NASA Astrophysics Data System (ADS)

    Whitfield, James; Faccin, Mauro; Biamonte, Jacob

    2013-03-01

    Designing and optimizing cost functions and energy landscapes is a problem encountered in many fields of science and engineering. These landscapes and cost functions can be embedded and annealed in experimentally controllable spin Hamiltonians. Using an approach based on group theory and symmetries, we examine the embedding of Boolean logic gates into the ground-state subspace of such spin systems. We describe parameterized families of diagonal Hamiltonians and symmetry operations which preserve the ground-state subspace encoding the truth tables of Boolean formulas. The ground-state embeddings of adder circuits are used to illustrate how gates are combined and simplified using symmetry. Our work is relevant for experimental demonstrations of ground-state embeddings found in both classical optimization as well as adiabatic quantum optimization.

  18. Geochemical processes controlling selenium in ground water after mining, Powder River Basin, Wyoming, U.S.A.

    USGS Publications Warehouse

    Naftz, D.L.; Rice, J.A.

    1989-01-01

    Geochemical data for samples of overburden from three mines in the Powder River Basin indicate a statistically significant (0.01 confidence level) positive correlation (r = 0.74) between Se and organic C. Results of factor analysis with varimax rotation on the major and trace element data from the rock samples indicate large (>50) varimax loadings for Se in two of the three factors. In Factor 1, the association of Se with constituents common to detrital grains indicates that water transporting the detrital particles into the Powder River Basin also carried dissolved Se. The large (>50) varimax loadings of Se and organic C in Factor 2 probably are due to the organic affinities characteristic of Se. Dissolved Se concentrations in water samples collected at one coal mine are directly related to the dissolved organic C concentrations. Hydrophilic acid concentrations in the water samples from the mine ranged from 35 to 43% of the total dissolved organic C, and hydrophobic acid concentrations ranged from 40 to 49% of the total dissolved organic C. The largest dissolved organic C concentrations in water from the same mine (34-302 mg/l), coupled with the large proportion of acidic components, may saturate adsorption sites on geothite and similar minerals that comprise the aquifer material, thus decreasing the extent of selenite (SeO32-) adsorption as a sink for Se as the redox state of ground water decreases. ?? 1989.

  19. Ground Zero.

    ERIC Educational Resources Information Center

    Lozada, Marlene

    1998-01-01

    Many public school districts have adopted a policy of zero tolerance toward drug use, weapon possession, and sexual harassment on school grounds. Although a study by the National Center for Education Statistics reported no evidence that zero tolerance policies have lowered school crime rates, prominent education groups favor them. (JOW)

  20. Escape and evade control policies for ensuring the physical security of nonholonomic, ground-based, unattended mobile sensor nodes

    NASA Astrophysics Data System (ADS)

    Mascarenas, David; Stull, Christopher; Farrar, Charles

    2011-06-01

    In order to realize the wide-scale deployment of high-endurance, unattended mobile sensing technologies, it is vital to ensure the self-preservation of the sensing assets. Deployed mobile sensor nodes face a variety of physical security threats including theft, vandalism and physical damage. Unattended mobile sensor nodes must be able to respond to these threats with control policies that facilitate escape and evasion to a low-risk state. In this work the Precision Immobilization Technique (PIT) problem has been considered. The PIT maneuver is a technique that a pursuing, car-like vehicle can use to force a fleeing vehicle to abruptly turn ninety degrees to the direction of travel. The abrupt change in direction generally causes the fleeing driver to lose control and stop. The PIT maneuver was originally developed by law enforcement to end vehicular pursuits in a manner that minimizes damage to the persons and property involved. It is easy to imagine that unattended autonomous convoys could be targets of this type of action by adversarial agents. This effort focused on developing control policies unattended mobile sensor nodes could employ to escape, evade and recover from PIT-maneuver-like attacks. The development of these control policies involved both simulation as well as small-scale experimental testing. The goal of this work is to be a step toward ensuring the physical security of unattended sensor node assets.

  1. GEOMORPHIC CONTROLS ON MEADOW ECOSYSTEMS – INSIGHTS INTO LOCAL PROCESSES USING NEAR-SURFACE SEISMIC TECHNIQUES AND GROUND PENETRATING RADAR

    EPA Science Inventory

    Geomorphic controls on riparian meadows in the Central Great Basin of Nevada are an important aspect in determining the formation of and planning the management of these systems. The current hypothesis is that both alluvial fan sediment and faulted bedrock steps interact to cont...

  2. Component testing of a ground based gas turbine steam cooled rich-burn primary zone combustor for emissions control of nitrogeneous fuels

    NASA Technical Reports Server (NTRS)

    Schultz, D. F.

    1986-01-01

    This effort summarizes the work performed on a steam cooled, rich-burn primary zone, variable geometry combustor designed for combustion of nitrogeneous fuels such as heavy oils or synthetic crude oils. The steam cooling was employed to determine its feasibility and assess its usefulness as part of a ground based gas turbine bottoming cycle. Variable combustor geometry was employed to demonstrate its ability to control primary and secondary zone equivalence ratios and overall pressure drop. Both concepts proved to be highly successful in achieving their desired objectives. The steam cooling reduced peak liner temperatures to less than 800 K. This low temperature offers the potential of both long life and reduced use of strategic materials for liner fabrication. These degrees of variable geometry were successfully employed to control air flow distribution within the combustor. A variable blade angle axial flow air swirler was used to control primary zone air flow, while the secondary and tertiary zone air flows were controlled by rotating bands which regulated air flow to the secondary zone quench holes and the dilutions holes respectively.

  3. Impact of synoptic controls and boundary layer processes on ground-level ozone evolution at an urban site

    NASA Astrophysics Data System (ADS)

    Haman, Christine Lanier

    Houston, Texas frequently exceeds the standard for ground-level ozone during the spring and fall. The large commuting population and vast number of industrial sources provide the necessary ingredients for photochemical ozone production in the presence of favorable meteorological conditions. The lack of continuous boundary layer (BL) observations prevents a comprehensive understanding of its role in ozone evolution. In this study, almost two years of BL observations are utilized to investigate the impacts of synoptic and micrometeorological-scale forcings on ozone. Aerosol gradients derived from ceilometer backscatter retrievals are used to identify the BL and residual layers (RL). Overall agreement is found between ceilometer and sonde estimates of the RL and BL heights (BLH), but difficulty detecting the layers occurs during cloud periods or immediately following precipitation. Large monthly variability is present in the peak afternoon BLH (e.g. mean August and December peaks are ˜2000 and 1100 m, respectively). Monthly nocturnal BLHs display much smaller differences. The majority of ozone exceedances occur during large-scale subsidence and weak winds in a postfrontal environment. These conditions result in turbulent kinetic energy, mechanical mixing, and ventilation processes that are 2--3 times weaker on exceedance days, which inhibit morning BL growth by an average of ˜100 m·hr-1 compared to low ozone days. The spring has higher nocturnal ozone levels, which is likely attributable to longer day lengths (˜78 minutes), stronger winds (˜0.78 m·s -1), and higher background ozone (˜5 ppbv) compared to the fall. Boundary layer entrainment plays an important role in ozone evolution. Exceedance days show a characteristic early morning rapid rise of ozone. Vertical ozone profiles indicate the RL ozone peak is ˜60 ppbv on exceedance days, which is ˜25 ppbv (+/- 10 ppbv) greater than low ozone days. The Integrated Profile Mixing (IPM) and Photochemical Budget (PB

  4. Controlled Ecological Life Support System. Design, Development, and Use of a Ground-Based Plant Growth Module

    NASA Technical Reports Server (NTRS)

    Macelroy, Robert D.; Smernoff, David T.; Rummel, John D.

    1987-01-01

    Problems of food production by higher plants are addressed. Experimentation requirements and necessary equipment for designing an experimental Controlled Ecological Life Support System (CELSS) Plant Growth Module are defined. A framework is provided for the design of laboratory sized plant growth chambers. The rationale for the development of an informal collaborative effort between investigators from universities and industry and those at Ames is evaluated. Specific research problems appropriate for collaborative efforts are identified.

  5. Mapping starting zone snow depth with a ground-based LiDAR to improve avalanche control and forecasting

    NASA Astrophysics Data System (ADS)

    Deems, J. S.; Gadomski, P. J.; Vellone, D.; Evanczyk, R.; LeWinter, A. L.; Birkeland, K.; Finnegan, D. C.

    2014-12-01

    The varying distribution of snow depth in avalanche starting zones exerts a strong influence on avalanche potential and character. Extreme depth changes over short distances are common, especially in wind-affected, above-treeline environments. Snow depth also affects the ease of avalanche triggering. Experience shows that avalanche reduction efforts are often more successful when targeting shallow trigger point areas near deeper slabs with explosives or ski cutting. Our pilot study explores the use of high resolution snow depth and depth change maps from differential LiDAR scans to quantify loading patterns for use in both pre-control planning and in post-control assessment. We present results from our initial work at the Arapahoe Basin Ski Area in Colorado, USA. A-Basin has a large number avalanche starting zones above treeline at elevations up to 4,000 m. The three study areas represent a range of institutional avalanche management history - the East Wall has been operated since 1970, Montezuma Bowl since 2008, and the Steep Gullies are under study for area expansion. Summer mapping produced a zero depth surface. Mapping multiple times during the snow season allowed us to produce time series maps of snow depth and snow depth change at high resolution to explore depth and slab thickness variations due to wind redistribution. We conducted surveys before and after loading events and control work, allowing the exploration of loading patterns, slab thickness, shot and ski cut locations, bed surfaces, entrainment, and avalanche characteristics. We also evaluate the state of terrestrial laser scanning for use in operational settings.

  6. Finite-element-analysis model and preliminary ground testing of controls-structures interaction evolutionary model reflector

    NASA Technical Reports Server (NTRS)

    Reaves, Mercedes C.; Belvin, W. Keith; Bailey, James P.

    1992-01-01

    Results of two different nonlinear finite element analyses and preliminary test results for the final design of the Controls-Structures Interaction Evolutionary Model are presented. Load-deflection data bases are generalized from analysis and testing of the 16-foot diameter, dish shaped reflector. Natural frequencies and mode shapes are obtained from vibrational analysis. Experimental and analytical results show similar trends; however, future test hardware modifications and finite element model refinement would be necessary to obtain better correlation. The two nonlinear analysis procedures are both adequate techniques for the analysis of prestressed structures with complex geometries.

  7. Integrated Heat Pump (IHP) System Development - Air-Source IHP Control Strategy and Specifications and Ground-Source IHP Conceptual Design

    SciTech Connect

    Murphy, Richard W; Rice, C Keith; Baxter, Van D

    2007-05-01

    The integrated heat pump (IHP), as one appliance, can provide space cooling, heating, ventilation, and dehumidification while maintaining comfort and meeting domestic water heating needs in near-zero-energy home (NZEH) applications. In FY 2006 Oak Ridge National Laboratory (ORNL) completed development of a control strategy and system specification for an air-source IHP. The conceptual design of a ground-source IHP was also completed. Testing and analysis confirm the potential of both IHP concepts to meet NZEH energy services needs while consuming 50% less energy than a suite of equipment that meets current minimum efficiency requirements. This report is in fulfillment of an FY06 DOE Building Technologies (BT) Joule Milestone.

  8. Survivability enhancement study for C/sup 3/I/BM (communications, command, control and intelligence/battle management) ground segments: Final report

    SciTech Connect

    Not Available

    1986-10-30

    This study involves a concept developed by the Fairchild Space Company which is directly applicable to the Strategic Defense Initiative (SDI) Program as well as other national security programs requiring reliable, secure and survivable telecommunications systems. The overall objective of this study program was to determine the feasibility of combining and integrating long-lived, compact, autonomous isotope power sources with fiber optic and other types of ground segments of the SDI communications, command, control and intelligence/battle management (C/sup 3/I/BM) system in order to significantly enhance the survivability of those critical systems, especially against the potential threats of electromagnetic pulse(s) (EMP) resulting from high altitude nuclear weapon explosion(s). 28 figs., 2 tabs.

  9. A comparison of lower limb EMG and ground reaction forces between barefoot and shod gait in participants with diabetic neuropathic and healthy controls

    PubMed Central

    2010-01-01

    Background It is known that when barefoot, gait biomechanics of diabetic neuropathic patients differ from non-diabetic individuals. However, it is still unknown whether these biomechanical changes are also present during shod gait which is clinically advised for these patients. This study investigated the effect of the participants own shoes on gait biomechanics in diabetic neuropathic individuals compared to barefoot gait patterns and healthy controls. Methods Ground reaction forces and lower limb EMG activities were analyzed in 21 non-diabetic adults (50.9 ± 7.3 yr, 24.3 ± 2.6 kg/m2) and 24 diabetic neuropathic participants (55.2 ± 7.9 yr, 27.0 ± 4.4 kg/m2). EMG patterns of vastus lateralis, lateral gastrocnemius and tibialis anterior, along with the vertical and antero-posterior ground reaction forces were studied during shod and barefoot gait. Results Regardless of the disease, walking with shoes promoted an increase in the first peak vertical force and the peak horizontal propulsive force. Diabetic individuals had a delay in the lateral gastrocnemius EMG activity with no delay in the vastus lateralis. They also demonstrated a higher peak horizontal braking force walking with shoes compared to barefoot. Diabetic participants also had a smaller second peak vertical force in shod gait and a delay in the vastus lateralis EMG activity in barefoot gait compared to controls. Conclusions The change in plantar sensory information that occurs when wearing shoes revealed a different motor strategy in diabetic individuals. Walking with shoes did not attenuate vertical forces in either group. Though changes in motor strategy were apparent, the biomechanical did not support the argument that the use of shoes contributes to altered motor responses during gait. PMID:20128894

  10. Bacillus thuringiensis var. israelensis Misting for Control of Aedes in Cryptic Ground Containers in North Queensland, Australia

    PubMed Central

    Jacups, Susan P.; Rapley, Luke P.; Johnson, Petrina H.; Benjamin, Seleena; Ritchie, Scott A.

    2013-01-01

    In Australia, dengue is not endemic, although the vector mosquito Aedes aegypti is established in far north Queensland (FNQ). Aedes albopictus has recently invaded the Torres Strait region, but is not established on mainland Australia. To maintain dengue-free, public health departments in FNQ closely monitor introduced dengue infections and confine outbreaks through rigorous vector control responses. To safeguard mainland Australia from Ae. albopictus establishment, pre-emptive strategies are required to reduce its breeding in difficult to access habitats. We compare the residual efficacy of VectoBac WDG, Bacillus thuringiensis var. israelensis (Bti) formulation, as a residual treatment when misted across a typical FNQ bushland using a backpack mister (Stihl SR 420 Mist Blower) at two dose rates up to 16 m. Semi-field condition results, over 16 weeks, indicate that Bti provided high mortality rates (> 80%) sustained for 11 weeks. Mist application penetrated 16 m of dense bushland without efficacy decline over distance. PMID:23358637

  11. Geohydrologic, geochemical, and geologic controls on the occurrence of radon in ground water near Conifer, Colorado, USA

    USGS Publications Warehouse

    Lawrence, E.; Poeter, E.; Wanty, R.

    1991-01-01

    Integrated studies of geohydrology, geochemistry, and geology of crystalline rocks in the vicinity of Conifer, Colorado, reveal that radon concentrations do not correlate with variations in concentrations of other dissolved species. Concentrations of major ions show systematic variations along selected groundwater flowpaths, whereas radon concentrations are dependent on local geochemical and geologic phenomena (such as localized uranium concentration in the rock or the presence of faults or folds). When radon enters the flow system, concentrations do not increase along flowpaths because its decay rate is fast relative to groundwater flow rates. Radon-222 is not in secular equilibrium with 238U and 226Ra in the water. Therefore, most of the 238U and 226Ra necessary to support the waterborne 222Rn must be present locally in the rock. High concentrations of dissolved radon are not found in zones of high transmissivity, and transmissivity is not correlated with rock type in the study area. A higher transmissivity can be indicative of higher water-volume to rock-surface-area ratios, which could effectively dilute 222Rn entering the water and/or may indicate that emanated radon is carried away more rapidly. Water samples collected from individual wells over periods of several months showed significant fluctuations in the dissolved 222Rn content. This fluctuation may be controlled by changes in the contributions of water-producing zones within the well resulting from seasonal fluctuations of the water table and/or pumping stresses. ?? 1991.

  12. Evaluation of Thermal Control Coatings and Polymeric Materials Exposed to Ground Simulated Atomic Oxygen and Vacuum Ultraviolet Radiation

    NASA Technical Reports Server (NTRS)

    Kamenetzky, R. R.; Vaughn, J. A.; Finckenor, M. M.; Linton, R. C.

    1995-01-01

    Numerous thermal control and polymeric samples with potential International Space Station applications were evaluated for atomic oxygen and vacuum ultraviolet radiation effects in the Princeton Plasma Physics Laboratory 5 eV Neutral Atomic Oxygen Facility and in the MSFC Atomic Oxygen Drift Tube System. Included in this study were samples of various anodized aluminum samples, ceramic paints, polymeric materials, and beta cloth, a Teflon-impregnated fiberglass cloth. Aluminum anodizations tested were black duranodic, chromic acid anodize, and sulfuric acid anodize. Paint samples consisted of an inorganic glassy black paint and Z-93 white paint made with the original PS7 binder and the new K2130 binder. Polymeric samples evaluated included bulk Halar, bulk PEEK, and silverized FEP Teflon. Aluminized and nonaluminized Chemfab 250 beta cloth were also exposed. Samples were evaluated for changes in mass, thickness, solar absorptance, and infrared emittance. In addition to material effects, an investigation was made comparing diffuse reflectance/solar absorptance measurements made using a Beckman DK2 spectroreflectometer and like measurements made using an AZ Technology-developed laboratory portable spectroreflectometer.

  13. Ground-based time-guidance algorithm for control of airplanes in a time-metered air traffic control environment: A piloted simulation study

    NASA Technical Reports Server (NTRS)

    Knox, C. E.; Imbert, N.

    1986-01-01

    The rapidly increasing costs of flight operations and the requirement for increased fuel conservation have made it necessary to develop more efficient ways to operate airplanes and to control air traffic for arrivals and departures to the terminal area. One concept of controlling arrival traffic through time metering has been jointly studied and evaluated by NASA and ONERA/CERT in piloted simulation tests. From time errors attained at checkpoints, airspeed and heading commands issued by air traffic control were computed by a time-guidance algorithm for the pilot to follow that would cause the airplane to cross a metering fix at a preassigned time. These tests resulted in the simulated airplane crossing a metering fix with a mean time error of 1.0 sec and a standard deviation of 16.7 sec when the time-metering algorithm was used. With mismodeled winds representing the unknown in wind-aloft forecasts and modeling form, the mean time error attained when crossing the metering fix was increased and the standard deviation remained approximately the same. The subject pilots reported that the airspeed and heading commands computed in the guidance concept were easy to follow and did not increase their work load above normal levels.

  14. Response of the summertime ground-level ozone trend in the Chicago area to emission controls and temperature changes, 2005-2013

    NASA Astrophysics Data System (ADS)

    Jing, Ping; Lu, Zifeng; Xing, Jia; Streets, David G.; Tan, Qian; O'Brien, Timothy; Kamberos, Joseph

    2014-12-01

    Despite strenuous efforts to reduce the emissions of ozone precursors such as nitrogen oxides (NOx), concentrations of ground-level ozone (O3) still often exceed the National Ambient Air Quality Standard in U.S. cities in summertime, including Chicago. Furthermore, studies have projected a future increase in O3 formation due to global climate change. This study examines the response of summertime O3 to emission controls and temperature change in the Chicago area from 2005 to 2013 by employing observations of O3, O3 precursors, and meteorological variables. We find that meteorology explains about 53% of the O3 variance in Chicago. O3 mixing ratios over Chicago are found to show no clear decline over the 2005-2013 period. The summertime ground-level O3 trend consists of a decrease of 0.08 ppb/year between 2005 and 2009 and an increase of 1.49 ppb/year between 2009 and 2013. Emissions of NOx and concentrations of NO2 have been decreasing steadily from 2005 to 2013 in the Chicago area. Concentrations of volatile organic compounds (VOCs) in Chicago, however, have more than doubled since 2009, even though emission inventories suggest that VOC emissions have decreased. We believe that O3 production in Chicago became more sensitive to VOCs starting in 2008/2009 and may have switched from being NOx-limited to VOC-limited. The warmer climate since 2008 has also contributed to the increasing ozone trend in the Chicago area. Increased attention should be paid to improving the quantification of VOC sources, enhancing the monitoring of reactive VOC concentrations, and designing VOC mitigation measures.

  15. Wind-induced ground motion

    NASA Astrophysics Data System (ADS)

    Naderyan, Vahid; Hickey, Craig J.; Raspet, Richard

    2016-02-01

    Wind noise is a problem in seismic surveys and can mask the seismic signals at low frequency. This research investigates ground motions caused by wind pressure and shear stress perturbations on the ground surface. A prediction of the ground displacement spectra using the measured ground properties and predicted pressure and shear stress at the ground surface is developed. Field measurements are conducted at a site having a flat terrain and low ambient seismic noise. Triaxial geophones are deployed at different depths to study the wind-induced ground vibrations as a function of depth and wind velocity. Comparison of the predicted to the measured wind-induced ground displacement spectra shows good agreement for the vertical component but significant underprediction for the horizontal components. To validate the theoretical model, a test experiment is designed to exert controlled normal pressure and shear stress on the ground using a vertical and a horizontal mass-spring apparatus. This experiment verifies the linear elastic rheology and the quasi-static displacements assumptions of the model. The results indicate that the existing surface shear stress models significantly underestimate the wind shear stress at the ground surface and the amplitude of the fluctuation shear stress must be of the same order of magnitude as the normal pressure. Measurement results show that mounting the geophones flush with the ground provides a significant reduction in wind noise on all three components of the geophone. Further reduction in wind noise with depth of burial is small for depths up to 40 cm.

  16. Regional analysis of ground and above-ground climate

    NASA Astrophysics Data System (ADS)

    1981-12-01

    The regional suitability of underground construction as a climate control technique is discussed with reference to (1) a bioclimatic analysis of long term weather data for 29 locations in the United States to determine appropriate above ground climate control techniques, (2) a data base of synthesized ground temperatures for the coterminous United States, and (3) monthly dew point ground temperature comparisons for identifying the relative likelihood of condensation from one region to another. It is concluded that the suitability of Earth tempering as a practice and of specific Earth sheltered design stereotypes varies geographically; while the subsurface almost always provides a thermal advantage on its own terms when compared to above ground climatic data, it can, nonetheless, compromise the effectiveness of other, regionally more important climate control techniques. Reviews of above and below ground climate mapping schemes related to human comfort and architectural design, and detailed description of a theoretical model of ground temperature, heat flow, and heat storage in the ground are included. Strategies of passive climate control are presented in a discussion of the building bioclimatic analysis procedure which has been applied in a computer analysis of 30 years of weather data for each of 20 locations in the United States.

  17. Regional analysis of ground and above-ground climate

    SciTech Connect

    Not Available

    1981-12-01

    The regional suitability of underground construction as a climate control technique is discussed with reference to (1) a bioclimatic analysis of long-term weather data for 29 locations in the United States to determine appropriate above ground climate control techniques, (2) a data base of synthesized ground temperatures for the coterminous United States, and (3) monthly dew point ground temperature comparisons for identifying the relative likelihood of condensation from one region to another. It is concluded that the suitability of earth tempering as a practice and of specific earth-sheltered design stereotypes varies geographically; while the subsurface almost always provides a thermal advantage on its own terms when compared to above ground climatic data, it can, nonetheless, compromise the effectiveness of other, regionally more important climate control techniques. Also contained in the report are reviews of above and below ground climate mapping schemes related to human comfort and architectural design, and detailed description of a theoretical model of ground temperature, heat flow, and heat storage in the ground. Strategies of passive climate control are presented in a discussion of the building bioclimatic analysis procedure which has been applied in a computer analysis of 30 years of weather data for each of 29 locations in the United States.

  18. High voltage lightning grounding device

    NASA Technical Reports Server (NTRS)

    Hoffman, R. G.; Peterson, V. S.

    1971-01-01

    Grounding device insertion in wire termination cabinets and terminal block modification prevent lightning-induced high voltage transients from reaching inputs or outputs of solid state instruments and control systems. Installation minimizes wiring confusion and achieves 100 percent protection.

  19. Contamination Control and Evaluation for Manufacturing, Ground Tests, Flight Operation and Post-Retrieval Analyses of the TANPOPO Exposed Panels and Capture Panels

    NASA Astrophysics Data System (ADS)

    Yano, Hajime; Hashimoto, Hirofumi; Kawaguchi, Yuko; Yokobori, Shin-ichi; Uchihori, Yukio; Tabata, Makoto; Yamagishi, Akihiko; Sasaki, Satoshi; Imai, Eiichi

    The TANPOPO (“dandelion” in Japanese) is Japan’s first astrobiology space experiment to be exposed on and retrieved from the ISS-Kibo Exposed Facility from the 2014-5 timeframe. During its 1-3 years of continuous exposure operation in the low earth orbit (LEO) of the Earth, it aims to test key questions consisted of the “quasi-panspermia” hypothesis, a theory for exogenesis origin of life and their precursor transports among celestial bodies The TANPOPO experiment consists of following six sub-themes (ST): 1) the first intact capture of terrestrial microbial colonies in LEO, 2) survival test of terrestrial microbes long exposed in LEO, 3) alteration tests of artificially composed “astronomical organic analogs” long exposed in LEO, 4) intact capture of organic-bearing micrometeoroids with the lowest peak temperature ever in LEO, 5) space flight verification of the world’s lowest density aerogels for intact capture of microparticles, and 6) meteoroid and orbital debris flux assessment only capable to be measured in-situ in LEO. Each will utilize one or more Capture Panel(CP) and Exposure Panel (EP) samples from various pointing faces onboard the Kibo Exposed Facility, i.e., anti-Earth pointing face(Space), leading face (East) and anti-Pressurized Facility face (North), as the ISS is an Earth gravity gradient three-axis stabilized satellite. In order to both satisfy scientific values and planetary protection policy, contamination control and evaluation protocols are implemented for the whole process of manufacturing, ground tests, flight operation and post-retrieval initial analyses of both CPs and EPs. The CPs employ blocks of 0.01g/ccultra-low dense aerogels on its to intact capture impacting solid microparticles such as organic-bearing micrometeoroids, artificial orbital debris and possible terrestrial aerosols temporally reached to the LEO, for assessing the possibility of interplanetary transport of life and its precursors. By analyzing them

  20. Human-robot interaction modeling and simulation of supervisory control and situational awareness during field experimentation with military manned and unmanned ground vehicles

    NASA Astrophysics Data System (ADS)

    Johnson, Tony; Metcalfe, Jason; Brewster, Benjamin; Manteuffel, Christopher; Jaswa, Matthew; Tierney, Terrance

    2010-04-01

    The proliferation of intelligent systems in today's military demands increased focus on the optimization of human-robot interactions. Traditional studies in this domain involve large-scale field tests that require humans to operate semiautomated systems under varying conditions within military-relevant scenarios. However, provided that adequate constraints are employed, modeling and simulation can be a cost-effective alternative and supplement. The current presentation discusses a simulation effort that was executed in parallel with a field test with Soldiers operating military vehicles in an environment that represented key elements of the true operational context. In this study, "constructive" human operators were designed to represent average Soldiers executing supervisory control over an intelligent ground system. The constructive Soldiers were simulated performing the same tasks as those performed by real Soldiers during a directly analogous field test. Exercising the models in a high-fidelity virtual environment provided predictive results that represented actual performance in certain aspects, such as situational awareness, but diverged in others. These findings largely reflected the quality of modeling assumptions used to design behaviors and the quality of information available on which to articulate principles of operation. Ultimately, predictive analyses partially supported expectations, with deficiencies explicable via Soldier surveys, experimenter observations, and previously-identified knowledge gaps.

  1. Effectiveness of riparian buffers in controlling ground-water discharge of nitrate to streams in selected hydrogeologic settings of the North Carolina Coastal Plain

    USGS Publications Warehouse

    Spruill, T.B.

    2004-01-01

    Water-quality and hydrologic information were collected along ground-water flow paths from two well-drained and two poorly drained Coastal Plain settings in North Carolina to evaluate the relative effectiveness of riparian buffers in reducing discharge of nitrate to streams. At one well-drained site with a 100 m buffer, little or no effect was detected on surface-water quality by discharging ground water because extensive woody vegetation in the buffer was able to take up not only most nitrate, but also most ground water before discharging to the stream during the growing season (March-October). At the second well-drained site, ground water discharging to the stream from the side with a buffer contained about 2 mg/L of nitrate-nitrogen after passing through the bed of the stream compared to 6 mg/L in ground water discharging from the side with no buffer. In the poorly drained settings, nitrate in ground water decreased from about 6 mg/L in the recharge area to less than 0.02 mg/L downgradient from the riparian buffer. Ground water discharging from the side with no buffer contained 0.83 mg/L. Riparian buffers appear effective in reducing nitrate in ground water discharging to Coast Plain streams. ?? US Government 2004.

  2. Control of groundwater pH during bioremediation: Improvement and validation of a geochemical model to assess the buffering potential of ground silicate minerals

    NASA Astrophysics Data System (ADS)

    Lacroix, Elsa; Brovelli, Alessandro; Holliger, Christof; Barry, D. A.

    2014-05-01

    Accurate control of groundwater pH is of critical importance for in situ biological treatment of chlorinated solvents. The use of ground silicate minerals mixed with groundwater is an appealing buffering strategy as silicate minerals may act as long-term sources of alkalinity. In a previous study, we developed a geochemical model for evaluation of the pH buffering capacity of such minerals. The model included the main microbial processes driving groundwater acidification as well as mineral dissolution. In the present study, abiotic mineral dissolution experiments were conducted with five silicate minerals (andradite, diopside, fayalite, forsterite, nepheline). The goal of the study was to validate the model and to test the buffering capacity of the candidate minerals identified previously. These five minerals increased the pH from acidic to neutral and slightly basic values. The model was revised and improved to represent better the experimental observations. In particular, the experiments revealed the importance of secondary mineral precipitation on the buffering potential of silicates, a process not included in the original formulation. The main secondary phases likely to precipitate were identified through model calibration, as well as the degree of saturation at which they formed. The predictions of the revised geochemical model were in good agreement with the observations, with a correlation coefficient higher than 0.9 in most cases. This study confirmed the potential of silicates to act as pH control agents and showed the reliability of the geochemical model, which can be used as a design tool for field applications.

  3. Utilizing remote sensing to supplement ground monitoring of Diorhabda elongata as a control agent for Tamarix ramosissima in Dinosaur National Monument

    NASA Astrophysics Data System (ADS)

    Archambault, V.; Auch, J.; Landy, J.; Rudy, G.; Seifert, C.; Schmidt, C.; Skiles, J.

    2008-12-01

    The plant Tamarix ramosissima has invaded significant riparian habitat along the Green River in Dinosaur National Monument. Commonly known as salt cedar or tamarisk, it was introduced from Eurasia to the Southwestern United States to prevent soil erosion along riverbanks and as an ornamental plant. It has since come to affect water resources, recreation, wildlife, and ecosystem services. Various methods used to control tamarisk's spread have had moderate success but have drained National Park Service of human and monetary resources. In June 2006, the salt cedar leaf beetle (Diorhabda elongata) was released as a biological control agent within the park to defoliate and ultimately eradicate the invasive species. This study examines the efficacy of using Landsat TM imagery to supplement ground monitoring of the beetle's spread and its effects on tamarisk in Dinosaur National Monument, and discusses the development of a GIS model to predict annual change in tamarisk cover and beetle populations. Through fieldwork, we determined four areas of interest with favorable attributes for satellite detection. A change detection model was created by layering 2005-2008 data and quantifying mean NDVI. Results show that intra-year NDVI trends may be more effective for accurate detection than single-image year-to-year comparisons largely because intra-year environmental variability is significantly smaller. Additionally, our GIS model predicted significant growth of beetle population, implying that defoliation will become more apparent in future years. However, challenges to detecting this defoliation include the year-to-year variability of environmental factors, low spatial resolution of Landsat TM data, low visibility into parts of the Green River canyon, and the spectral mixing of tamarisk and native vegetation.

  4. Non-invasive cardiac assessment in high risk patients (The GROUND study): rationale, objectives and design of a multi-center randomized controlled clinical trial

    PubMed Central

    de Vos, Alexander M; Rutten, Annemarieke; van de Zaag-Loonen, Hester J; Bots, Michiel L; Dikkers, Riksta; Buiskool, Robert A; Mali, Willem P; Lubbers, Daniel D; Mosterd, Arend; Prokop, Mathias; Rensing, Benno J; Cramer, Maarten J; van Es, H Wouter; Moll, Frans L; van de Pavoordt, Eric D; Doevendans, Pieter A; Velthuis, Birgitta K; Mackaay, Albert J; Zijlstra, Felix; Oudkerk, Matthijs

    2008-01-01

    Background Peripheral arterial disease (PAD) is a common disease associated with a considerably increased risk of future cardiovascular events and most of these patients will die from coronary artery disease (CAD). Screening for silent CAD has become an option with recent non-invasive developments in CT (computed tomography)-angiography and MR (magnetic resonance) stress testing. Screening in combination with more aggressive treatment may improve prognosis. Therefore we propose to study whether a cardiac imaging algorithm, using non-invasive imaging techniques followed by treatment will reduce the risk of cardiovascular disease in PAD patients free from cardiac symptoms. Design The GROUND study is designed as a prospective, multi-center, randomized clinical trial. Patients with peripheral arterial disease, but without symptomatic cardiac disease will be asked to participate. All patients receive a proper risk factor management before randomization. Half of the recruited patients will enter the 'control group' and only undergo CT calcium scoring. The other half of the recruited patients (index group) will undergo the non invasive cardiac imaging algorithm followed by evidence-based treatment. First, patients are submitted to CT calcium scoring and CT angiography. Patients with a left main (or equivalent) coronary artery stenosis of > 50% on CT will be referred to a cardiologist without further imaging. All other patients in this group will undergo dobutamine stress magnetic resonance (DSMR) testing. Patients with a DSMR positive for ischemia will also be referred to a cardiologist. These patients are candidates for conventional coronary angiography and cardiac interventions (coronary artery bypass grafting (CABG) or percutaneous cardiac interventions (PCI)), if indicated. All participants of the trial will enter a 5 year follow up period for the occurrence of cardiovascular events. Sequential interim analysis will take place. Based on sample size calculations about

  5. Ground water contamination

    SciTech Connect

    Not Available

    1991-01-01

    This book covers: Ground water contamination and basic concepts of water law; Federal law governing water contamination and remediation; Ground water flow and contaminant migration; Ground water cleanup under CERCLA; Technical methods of remediation and prevention of contamination; Liability for ground water contamination; State constraints on contamination of ground water; Water quantity versus water quality; Prevention of use of contaminated ground water as an alternative to remediation; Economic considerations in liability for ground water contamination; and Contamination, extraction, and injection issues.

  6. Accuracy and precision of porosity estimates based on velocity inversion of surface ground-penetrating radar data: A controlled experiment at the Boise Hydrogeophysical Research Site

    NASA Astrophysics Data System (ADS)

    Bradford, J.; Clement, W.

    2006-12-01

    Although rarely acquired, ground penetrating radar (GPR) data acquired in continuous multi-offset geometries can substantially improve our understanding of the subsurface compared to conventional single offset surveys. This improvement arises because multi-offset data enable full use of the information that the GPR signal can carry. The added information allows us to maximize the material property information extracted from a GPR survey. Of the array of potential multi-offset GPR measurements, traveltime vs offset information enables laterally and vertically continuous electromagnetic (EM) velocity measurements. In turn, the EM velocities provide estimates of water content via petrophysical relationships such as the CRIM or Topp's equations. In fully saturated media the water content is a direct measure of bulk porosity. The Boise Hydrogeophysical Research Site (BHRS) is a experimental wellfield located in a shallow alluvial aquifer near Boise, Idaho. In July, 2006 we conducted a controlled 3D multi-offset GPR experiment at the BHRS designed to test the accuracy of state-of-the-art velocity analysis methodologies. We acquired continuous multi-offset GPR data over an approximately 20 x 30 m 3D area. The GPR system was a Sensors and Software pulseEkko Pro multichannel system with 100 MHz antennas and was configured with 4 receivers and a single transmitter. Data were acquired in off-end geometry for a total of 16 offsets with a 1 m offset interval and 1 m near offset. The data were acquired on a 1 m x 1m grid in four passes, each consisting of a 3 m range of equally spaced offsets. The survey encompassed 13 wells finished to the ~20 m depth of the unconfined aquifer. We established velocity control by acquiring vertical radar profiles (VRPs) in all 13 wells. Preliminary velocity measurements using an established method of reflection tomography were within about 1 percent of local 1D velocity distributions determined from the VRPs. Vertical velocity precision from the

  7. Effects of ground and joint reaction force exercise on lumbar spine and femoral neck bone mineral density in postmenopausal women: a meta-analysis of randomized controlled trials

    PubMed Central

    2012-01-01

    Background Low bone mineral density (BMD) and subsequent fractures are a major public health problem in postmenopausal women. The purpose of this study was to use the aggregate data meta-analytic approach to examine the effects of ground (for example, walking) and/or joint reaction (for example, strength training) exercise on femoral neck (FN) and lumbar spine (LS) BMD in postmenopausal women. Methods The a priori inclusion criteria were: (1) randomized controlled trials, (2) exercise intervention ≥ 24 weeks, (3) comparative control group, (4) postmenopausal women, (5) participants not regularly active, i.e., less than 150 minutes of moderate intensity (3.0 to 5.9 metabolic equivalents) weight bearing endurance activity per week, less than 75 minutes of vigorous intensity (> 6.0 metabolic equivalents) weight bearing endurance activity per week, resistance training < 2 times per week, (6) published and unpublished studies in any language since January 1, 1989, (7) BMD data available at the FN and/or LS. Studies were located by searching six electronic databases, cross-referencing, hand searching and expert review. Dual selection of studies and data abstraction were performed. Hedge’s standardized effect size (g) was calculated for each FN and LS BMD result and pooled using random-effects models. Z-score alpha values, 95%confidence intervals (CI) and number-needed-to-treat (NNT) were calculated for pooled results. Heterogeneity was examined using Q and I2. Mixed-effects ANOVA and simple meta-regression were used to examine changes in FN and LS BMD according to selected categorical and continuous variables. Statistical significance was set at an alpha value ≤0.05 and a trend at >0.05 to ≤ 0.10. Results Small, statistically significant exercise minus control group improvements were found for both FN (28 g’s, 1632 participants, g = 0.288, 95% CI = 0.102, 0.474, p = 0.002, Q = 90.5, p < 0.0001, I2 = 70.1%, NNT = 6

  8. Ground-state spin logic

    NASA Astrophysics Data System (ADS)

    Whitfield, J. D.; Faccin, M.; Biamonte, J. D.

    2012-09-01

    Designing and optimizing cost functions and energy landscapes is a problem encountered in many fields of science and engineering. These landscapes and cost functions can be embedded and annealed in experimentally controllable spin Hamiltonians. Using an approach based on group theory and symmetries, we examine the embedding of Boolean logic gates into the ground-state subspace of such spin systems. We describe parameterized families of diagonal Hamiltonians and symmetry operations which preserve the ground-state subspace encoding the truth tables of Boolean formulas. The ground-state embeddings of adder circuits are used to illustrate how gates are combined and simplified using symmetry. Our work is relevant for experimental demonstrations of ground-state embeddings found in both classical optimization as well as adiabatic quantum optimization.

  9. Hydrologic characterization of the Fry Canyon, Utah site prior to field demonstration of reactive chemical barriers to control radionuclide and trace-element contamination in ground water

    SciTech Connect

    Naftz, D.L.; Freethey, G.W.; Davis, J.A.

    1997-12-31

    The Fry Canyon Site in southeastern Utah has been selected as a long term demonstration site to assess the performance of selected reaction barrier technologies for the removal of uranium and other trace elements from ground water. Objectives include site characterization and evaluation of barrier technologies.

  10. Strong ground motion generated by controlled blasting experiments and mining induced seismic events recorded underground at deep level mines in South Africa

    NASA Astrophysics Data System (ADS)

    Milev, A.; Selllers, E.; Skorpen, L.; Scheepers, L.; Murphy, S.; Spottiswoode, S. M.

    2011-12-01

    A number of simulated rockbursts were conducted underground at deep level gold mines in South Africa in order to estimate the rock mass response when subjected to strong ground motion. The rockbursts were simulated by means of large blasts detonated in solid rock close to the sidewall of a tunnel. The simulated rockbursts involved the design of the seismic source, seismic observations in the near and far field, high-speed video filming, a study of rock mass conditions such as fractures, joints, rock strength etc. Knowledge of the site conditions before and after the simulated rockbursts was also gained. The numerical models used in the design of the simulated rockbursts were calibrated by small blasts taking place at each experimental site. A dense array of shock type accelerometers was installed along the blasting wall to monitor the attenuation of the strong ground motion as a function of the distance from the source. The attenuation of peak particle velocities, was found to be proportional to R^-1.7. Special investigations were carried out to evaluate the mechanism and the magnitude of damage, as well as the support behaviour under excessive dynamic loading. The strong ground motion generated by mining induced seismic events was studied, as part of this work, not only to characterize the rock mass response, but also to estimate the site effect on the surface of the underground excavations. A stand-alone instrument especially designed for recording strong ground motions was used to create a large database of peak particle velocities measured on stope hangingwalls. A total number of 58 sites located in stopes where the Carbon Leader Reef, Ventersdorp Contact Reef, Vaal Reef and Basal Reef are mined, were monitored. The peak particle velocities were measured at the surface of the excavations to identify the effect of the free surface and the fractures surrounding the underground mining. Based on these measurements the generally accepted velocity criterion of 3 m

  11. Ground water and energy

    SciTech Connect

    Not Available

    1980-11-01

    This national workshop on ground water and energy was conceived by the US Department of Energy's Office of Environmental Assessments. Generally, OEA needed to know what data are available on ground water, what information is still needed, and how DOE can best utilize what has already been learned. The workshop focussed on three areas: (1) ground water supply; (2) conflicts and barriers to ground water use; and (3) alternatives or solutions to the various issues relating to ground water. (ACR)

  12. Ground difference compensating system

    DOEpatents

    Johnson, Kris W.; Akasam, Sivaprasad

    2005-10-25

    A method of ground level compensation includes measuring a voltage of at least one signal with respect to a primary ground potential and measuring, with respect to the primary ground potential, a voltage level associated with a secondary ground potential. A difference between the voltage level associated with the secondary ground potential and an expected value is calculated. The measured voltage of the at least one signal is adjusted by an amount corresponding to the calculated difference.

  13. How are the VLF quasi-periodic emissions controlled by harmonics of field line oscillations? - The results of a comparison between ground and GEOS satellites measurements

    NASA Astrophysics Data System (ADS)

    Tixier, M.; Cornilleau-Wehrlin, N.

    1986-06-01

    Data on VLF and UHF waves observed in situ for the first time by the GEOS 1 and 2 satellites close to the equatorial plane are compared with ground-based measurements. The results permit a more complete explanation of quasi-periodic (QP) modulation. The data are described, and a general ground-satellite comparison of occurrence and spectra of simultaneous emission is given. A detailed study of some selected events shows that, when the GEOS data are taken into account, it is sometimes difficult to classify QP emissions as either type I or type II. It is suggested that QPs may be due to the same mechanism involving compressional harmonics of a standing fundamental ULF wave.

  14. 30 CFR 57.3360 - Ground support use.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Ground support use. 57.3360 Section 57.3360... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Scaling and Support-Underground Only § 57.3360 Ground support use. Ground support shall be used where...

  15. 30 CFR 57.3360 - Ground support use.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Ground support use. 57.3360 Section 57.3360... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Scaling and Support-Underground Only § 57.3360 Ground support use. Ground support shall be used where...

  16. 30 CFR 57.3360 - Ground support use.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Ground support use. 57.3360 Section 57.3360... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Scaling and Support-Underground Only § 57.3360 Ground support use. Ground support shall be used where...

  17. 30 CFR 57.3360 - Ground support use.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Ground support use. 57.3360 Section 57.3360... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Scaling and Support-Underground Only § 57.3360 Ground support use. Ground support shall be used where...

  18. 30 CFR 57.3360 - Ground support use.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Ground support use. 57.3360 Section 57.3360... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Scaling and Support-Underground Only § 57.3360 Ground support use. Ground support shall be used where...

  19. Ground and flight test experience with a triple redundant digital fly by wire control system. [installed in F-8C aircraft

    NASA Technical Reports Server (NTRS)

    Jarvis, C. R.; Szalai, K. J.

    1981-01-01

    A triplex digital fly by wire flight control system was developed and installed in an F-8C aircraft to provide fail operative, full authority control. Hardware and software redundancy management techniques were designed to detect and identify failures in the system. Control functions typical of those projected for future actively controlled vehicles were implemented.

  20. Detachment of Tertiary Dendrite Arms during Controlled Directional Solidification in Aluminum - 7 wt Percent Silicon Alloys: Observations from Ground-based and Microgravity Processed Samples

    NASA Technical Reports Server (NTRS)

    Grugel, Richard N.; Erdman, Robert; Van Hoose, James R.; Tewari, Surendra; Poirier, David

    2012-01-01

    Electron Back Scattered Diffraction results from cross-sections of directionally solidified aluminum 7wt% silicon alloys unexpectedly revealed tertiary dendrite arms that were detached and mis-oriented from their parent arm. More surprisingly, the same phenomenon was observed in a sample similarly processed in the quiescent microgravity environment aboard the International Space Station (ISS) in support of the joint US-European MICAST investigation. The work presented here includes a brief introduction to MICAST and the directional solidification facilities, and their capabilities, available aboard the ISS. Results from the ground-based and microgravity processed samples are compared and possible mechanisms for the observed tertiary arm detachment are suggested.

  1. LINE-ABOVE-GROUND ATTENUATOR

    DOEpatents

    Wilds, R.B.; Ames, J.R.

    1957-09-24

    The line-above-ground attenuator provides a continuously variable microwave attenuator for a coaxial line that is capable of high attenuation and low insertion loss. The device consists of a short section of the line-above- ground plane type transmission lime, a pair of identical rectangular slabs of lossy material like polytron, whose longitudinal axes are parallel to and indentically spaced away from either side of the line, and a geared mechanism to adjust amd maintain this spaced relationship. This device permits optimum fineness and accuracy of attenuator control which heretofore has been difficult to achieve.

  2. Preventing ground water contamination

    SciTech Connect

    Thompson, R.

    1985-07-12

    A recent Office of Technology Assessment report to Congress indicates that the associated health risks from ground water contamination are likely to increase because federal and state laws provide inadequate protection. Road de-icing salts, pesticide runoff, septic tanks, and seepage from livestock manure and fertilizers are all major causes that are difficult to control. A primary source that can be corrected is improper or unsafe disposal of hazardous wastes that are dumped into landfills or surface ponds or injected into deep wells. Congress has tried to deal with the problem by strengthening existing and introducing new legislation. Because getting rid of hazardous waste is increasingly expensive and difficult, companies are beginning to look for ways to prevent pollution at the source by using new technologies that are economically sound. 17 references, 4 figures.

  3. Autonomous docking ground demonstration

    NASA Technical Reports Server (NTRS)

    Lamkin, Steve L.; Le, Thomas Quan; Othon, L. T.; Prather, Joseph L.; Eick, Richard E.; Baxter, Jim M.; Boyd, M. G.; Clark, Fred D.; Spehar, Peter T.; Teters, Rebecca T.

    1991-01-01

    The Autonomous Docking Ground Demonstration is an evaluation of the laser sensor system to support the docking phase (12 ft to contact) when operated in conjunction with the guidance, navigation, and control (GN&C) software. The docking mechanism being used was developed for the Apollo/Soyuz Test Program. This demonstration will be conducted using the 6-DOF Dynamic Test System (DTS). The DTS simulates the Space Station Freedom as the stationary or target vehicle and the Orbiter as the active or chase vehicle. For this demonstration, the laser sensor will be mounted on the target vehicle and the retroflectors will be on the chase vehicle. This arrangement was chosen to prevent potential damage to the laser. The laser sensor system, GN&C, and 6-DOF DTS will be operated closed-loop. Initial conditions to simulate vehicle misalignments, translational and rotational, will be introduced within the constraints of the systems involved.

  4. Advanced ground station architecture

    NASA Technical Reports Server (NTRS)

    Zillig, David; Benjamin, Ted

    1994-01-01

    This paper describes a new station architecture for NASA's Ground Network (GN). The architecture makes efficient use of emerging technologies to provide dramatic reductions in size, operational complexity, and operational and maintenance costs. The architecture, which is based on recent receiver work sponsored by the Office of Space Communications Advanced Systems Program, allows integration of both GN and Space Network (SN) modes of operation in the same electronics system. It is highly configurable through software and the use of charged coupled device (CCD) technology to provide a wide range of operating modes. Moreover, it affords modularity of features which are optional depending on the application. The resulting system incorporates advanced RF, digital, and remote control technology capable of introducing significant operational, performance, and cost benefits to a variety of NASA communications and tracking applications.

  5. GROUND WATER SAMPLING ISSUES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and
    remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  6. Ground Water Remediation Technologies

    EPA Science Inventory

    The USEPA's Ground Water and Ecosystems Restoration Division (GWERD) conducts research and provides technical assistance to support the development of strategies and technologies to protect and restore ground water, surface water, and ecosystems impacted by man-made and natural...

  7. LISA Pathfinder ground testing

    NASA Astrophysics Data System (ADS)

    Guzman, Felipe; LISA Pathfinder Team

    2010-01-01

    The space-based gravitational wave observatory LISA is a joint NASA-ESA mission that requires challenging technology to ensure pure geodetic trajectories of test masses and the interferometric measurement of distance variations between them. The LISA Pathfinder mission is an ESA-launched technology demonstrator of key LISA subsystems such as spacecraft control with micronewton thrusters, test mass drag-free control, and precision laser interferometry between free-flying test masses. Ground testing of pre-flight hardware of the Gravitational Reference Sensor and Optical Metrology subsystems is currently ongoing. Studies have been carried out on very sensitive torsion pendulums that effectively reproduce a free-fall condition for the test mass within a horizontal plane in the lab, down to frequencies < 0.1 mHz. Thermal gradient induced effects, impact of gas molecules, noisy charging, surface charge patches, and other effects have been investigated and their physical models consolidated. A final upper limit on non-modeled disturbances has also been obtained within one order of magnitude of LISA requirements at 1 mHz. The interferometry system has also been extensively studied to identify noise sources and develop approaches to mitigate them. Engineering models of the optical bench, laser head and laser modulators have been interconnected and tested for functionality and noise level in closed-loop operation, demonstrating the required optical metrology sensitivity to test mass displacement. This poster presents the current status in the development and implementation of LISA Pathfinder pre-flight systems and latest results of the ongoing ground testing efforts.

  8. The Static Longitudinal Stability and Control Characteristics in the Presence of the Ground of a Model Having a Triangular Wing and Canard

    NASA Technical Reports Server (NTRS)

    Buell, Donald A.; Tinling, Bruce E.

    1959-01-01

    A wind-tunnel investigation was made of the low-speed characteristics of a canard configuration having triangular wing and canard surfaces with an aspect ratio of 2. The exposed area of the canard was 6.9 percent of the total wing area. The canard hinge line was located at 0.35 of its mean aerodynamic chord and was 0.5 wing mean aerodynamic chord lengths forward of the wing apex. The ground effects, which made the lift more positive and the -Pitching moment more negative at a given angle of attack, were unaffected by the canard. The stability of the model at a constant canard hinge-moment coefficient decreased to 0 near a lift coefficient of 1.0. In addition, the maximum lift coefficient at which the canard could provide balance was decreased by ground effects to less than 1.0 if the moment center was as far forward as 0.21 of the wing mean aerodynamic chord. The relative magnitude of interference effects between the canard and the wing and body is presented.

  9. Measurement scheme for a ground-state parity non-conserving (PNC) measurement in a cesium atomic beam via two-pathway coherent control

    NASA Astrophysics Data System (ADS)

    Choi, Jungu; Elliott, Dan; Elliott's Lab Team

    2016-05-01

    We present a detailed analysis of an experimental setup for parity non-conserving (PNC) measurements in a cesium atomic beam. We employ a parallel-plate transmission line (PPTL) structure and highly reflective cylindrical mirrors to form a microwave cavity resonator to excite the PNC transitions in the cesium hyperfine ground states. In addition, a variable external dc field is applied to observe the Stark-induced transition, which would interfere with the PNC transition as the dc field amplitude changes. Finally, strong Raman lasers are used to excite the ground hyperfine transition. The Raman fields interfere with the weak transitions, and by varying the phase difference between the Raman fields and the microwave fields, we would infer the weak transition amplitudes from the signal modulation. The experimental setup requires maintaining coherent phase relations between all fields, well-characterized dc and rf field patterns, the two co-propagating Raman lasers, and suppression of the magnetic dipole contribution. Our analysis of the field modes supported by the PPTL structure indicates that with a moderate rf power and a few tens of seconds of data collection time, the PNC measurement of less than 3% uncertainty would be feasible.

  10. Ground water: a review.

    USGS Publications Warehouse

    Bredehoeft, J.D.

    1983-01-01

    There is growing documentation that a significant portion of the Nation's fresh ground water in the densely populated areas of the USA is contaminated. Because of the slow rates of ground-water movement, ground water once contaminated will remain so for decades, often longer. Cleanup of contaminated ground water is almost always expensive and often technically unfeasible; the expense is often prohibitive. -from Author

  11. 14 CFR 23.415 - Ground gust conditions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ground gust conditions. 23.415 Section 23... and System Loads § 23.415 Ground gust conditions. (a) The control system must be investigated as follows for control surface loads due to ground gusts and taxiing downwind: (1) If an investigation of...

  12. 14 CFR 25.415 - Ground gust conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ground gust conditions. 25.415 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.415 Ground... ground gusts and taxiing downwind: (1) The control system between the stops nearest the surfaces and...

  13. 14 CFR 25.415 - Ground gust conditions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ground gust conditions. 25.415 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.415 Ground... ground gusts and taxiing downwind: (1) The control system between the stops nearest the surfaces and...

  14. 14 CFR 23.415 - Ground gust conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ground gust conditions. 23.415 Section 23... and System Loads § 23.415 Ground gust conditions. (a) The control system must be investigated as follows for control surface loads due to ground gusts and taxiing downwind: (1) If an investigation of...

  15. 14 CFR 25.415 - Ground gust conditions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ground gust conditions. 25.415 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.415 Ground... ground gusts and taxiing downwind: (1) The control system between the stops nearest the surfaces and...

  16. 14 CFR 25.415 - Ground gust conditions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Ground gust conditions. 25.415 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Control Surface and System Loads § 25.415 Ground... ground gusts and taxiing downwind: (1) The control system between the stops nearest the surfaces and...

  17. Procedures for ground-water investigations

    SciTech Connect

    Not Available

    1992-12-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water monitoring procedures are developed and used in accordance with the PNL Quality Assurance Program.

  18. COMPILATION OF GROUND-WATER MODELS

    EPA Science Inventory

    Ground-water modeling is a computer-based methodology for mathematical analysis of the mechanisms and controls of ground-water systems for the evaluation of policies, action, and designs that may affect such systems. n addition to satisfying scientific interest in the workings of...

  19. 49 CFR 236.2 - Grounds.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., single-break, signal control circuits using a grounded common, and alternating current power distribution... internal to microprocessor-based appliances; (4) Circuitry internal to semiconductor-based memory; or (5) Alternating current power distribution circuits that are grounded in the interest of safety....

  20. Electrical Ground Support Equipment Fabrication, Specification for

    NASA Technical Reports Server (NTRS)

    Denson, Erik C.

    2014-01-01

    This document specifies parts, materials, and processes used in the fabrication, maintenance, repair, and procurement of electrical and electronic control and monitoring equipment associated with ground support equipment (GSE) at the Kennedy Space Center (KSC).

  1. Investigation of Longitudinal and Lateral Stability Characteristics of a Six-Propeller Deflected-Slipstream VTOL Model with Boundary-Layer Control Including Effects of Ground Proximity

    NASA Technical Reports Server (NTRS)

    Grunwald, Kalman J.

    1961-01-01

    An investigation of the longitudinal and lateral stability and control and Performance characteristics of a six-propeller deflected- slipstream vertical-take-off-and-landing (VTOL) model in the transition speed range was conducted in the 17-foot test section of the Langley 300-MPH 7- by 10-foot tunnel. A complete analysis of the data was not conducted. A modest amount of blowing boundary-layer control was necessary to achieve transition without wing stall.

  2. Endogenous control of sexual size dimorphism: Gonadal androgens have neither direct nor indirect effect on male growth in a Madagascar ground gecko (Paroedura picta).

    PubMed

    Kubička, Lukáš; Starostová, Zuzana; Kratochvíl, Lukáš

    2015-12-01

    Changes in the effect of gonadal androgens on male growth are considered as a possible mechanism allowing shifts in magnitude and even direction of sexual size dimorphism in vertebrates, particularly squamate reptiles. Positive effects of gonadal androgens on male growth were found in several male-larger species of lizards. Contrastingly, we document that in the male-larger Madagascar ground gecko (Paroedura picta) gonadal androgens do not affect male growth under constant thermal conditions. However, the absence of a thermal gradient might prevent the potential indirect effect of gonadal androgens on growth via the influence of circulating hormones on an individual's thermoregulation and hence metabolic rate. In order to study this, we monitored the growth and body temperature of socially isolated sham-operated and castrated males of the same species in a thermal gradient. We also compared the oxygen consumption and activity between the treatment groups in the open field to test the effect of gonadal hormones on these traits potentially affecting growth. Even under a thermal gradient we found no effect of gonadal androgens on growth rate or final body dimensions. Castration also did not significantly affect oxygen consumption or activity in the open field test. Together with our previous findings, we can exclude both the direct effect of male gonadal androgens on the ontogeny of sexual size dimorphism via the influence on the growth axis, and the indirect influence of gonadal androgens acting on the ontogeny of SSD through the effect on thermoregulation, metabolic rate and activity. PMID:26431613

  3. Spin-orbit coupling control of anisotropy, ground state and frustration in 5d2Sr2MgOsO6

    DOE PAGESBeta

    Morrow, Ryan; Taylor, Alice E.; Singh, D. J.; Xiong, Jie; Rodan, Steven; Wolter, A. U. B.; Wurmehl, Sabine; Büchner, Bernd; Stone, M. B.; Kolesnikov, A. I.; et al

    2016-08-30

    The influence of spin-orbit coupling (SOC) on the physical properties of the 5d2 system Sr2MgOsO6 is probed via a combination of magnetometry, specific heat measurements, elastic and inelastic neutron scattering, and density functional theory calculations. Although a significant degree of frustration is expected, we find that Sr2MgOsO6 orders in a type I antiferromagnetic structure at the remarkably high temperature of 108 K. The measurements presented allow for the first accurate quantification of the size of the magnetic moment in a 5d2 system of 0.60(2) μB a significantly reduced moment from the expected value for such a system. Furthermore, significant anisotropymore » is identified via a spin excitation gap, and we confirm by first principles calculations that SOC not only provides the magnetocrystalline anisotropy, but also plays a crucial role in determining both the ground state magnetic order and the moment size in this compound. In conclusion, through comparison to Sr2ScOsO6, it is demonstrated that SOC-induced anisotropy has the ability to relieve frustration in 5d2 systems relative to their 5d3 counterparts, providing an explanation of the high TN found in Sr2MgOsO6.« less

  4. Baseline data-collection and quality-control protocols and procedures for the Equus beds ground-water recharge demonstration project near Wichita, Kansas, 1995-96

    USGS Publications Warehouse

    Ziegler, A.C.; Combs, L.J.

    1997-01-01

    The Equus Beds Ground-Water Recharge Demonstration Project is being conducted from 1995 through 1999 as part of the High Plains States Groundwater Recharge Demonstration Program to determine if recharge of the Equus beds aquifer in south-central Kansas is a viable alternative in meeting the increased demands for water in this rapidly growing part of the State. As part of the demonstration project, protocols and procedures were developed for the collection of baseline hydrologic and water-quality data from September 1995 through September 1996 and are described in this report. During this initial phase of the demonstration project, 33 data-collection sites were identified and instrumented, and an aquifer test at one site was conducted to determine transmissivity, specific yield, hydraulic conductivity, and riverbed conductance of the Equus beds aquifer in the area northwest of Wichita, Kansas. Selected water-quality samples were analyzed for as many as 340 chemical constituents to determine the baseline or ambient concentrations of inorganic and orgainc constituents.

  5. Spin-orbit coupling control of anisotropy, ground state and frustration in 5d2 Sr2MgOsO6

    PubMed Central

    Morrow, Ryan; Taylor, Alice E.; Singh, D. J.; Xiong, Jie; Rodan, Steven; Wolter, A. U. B.; Wurmehl, Sabine; Büchner, Bernd; Stone, M. B.; Kolesnikov, A. I.; Aczel, Adam A.; Christianson, A. D.; Woodward, Patrick M.

    2016-01-01

    The influence of spin-orbit coupling (SOC) on the physical properties of the 5d2 system Sr2MgOsO6 is probed via a combination of magnetometry, specific heat measurements, elastic and inelastic neutron scattering, and density functional theory calculations. Although a significant degree of frustration is expected, we find that Sr2MgOsO6 orders in a type I antiferromagnetic structure at the remarkably high temperature of 108 K. The measurements presented allow for the first accurate quantification of the size of the magnetic moment in a 5d2 system of 0.60(2) μB –a significantly reduced moment from the expected value for such a system. Furthermore, significant anisotropy is identified via a spin excitation gap, and we confirm by first principles calculations that SOC not only provides the magnetocrystalline anisotropy, but also plays a crucial role in determining both the ground state magnetic order and the size of the local moment in this compound. Through comparison to Sr2ScOsO6, it is demonstrated that SOC-induced anisotropy has the ability to relieve frustration in 5d2 systems relative to their 5d3 counterparts, providing an explanation of the high TN found in Sr2MgOsO6. PMID:27571715

  6. Spin-orbit coupling control of anisotropy, ground state and frustration in 5d(2) Sr2MgOsO6.

    PubMed

    Morrow, Ryan; Taylor, Alice E; Singh, D J; Xiong, Jie; Rodan, Steven; Wolter, A U B; Wurmehl, Sabine; Büchner, Bernd; Stone, M B; Kolesnikov, A I; Aczel, Adam A; Christianson, A D; Woodward, Patrick M

    2016-01-01

    The influence of spin-orbit coupling (SOC) on the physical properties of the 5d(2) system Sr2MgOsO6 is probed via a combination of magnetometry, specific heat measurements, elastic and inelastic neutron scattering, and density functional theory calculations. Although a significant degree of frustration is expected, we find that Sr2MgOsO6 orders in a type I antiferromagnetic structure at the remarkably high temperature of 108 K. The measurements presented allow for the first accurate quantification of the size of the magnetic moment in a 5d(2) system of 0.60(2) μB -a significantly reduced moment from the expected value for such a system. Furthermore, significant anisotropy is identified via a spin excitation gap, and we confirm by first principles calculations that SOC not only provides the magnetocrystalline anisotropy, but also plays a crucial role in determining both the ground state magnetic order and the size of the local moment in this compound. Through comparison to Sr2ScOsO6, it is demonstrated that SOC-induced anisotropy has the ability to relieve frustration in 5d(2) systems relative to their 5d(3) counterparts, providing an explanation of the high TN found in Sr2MgOsO6. PMID:27571715

  7. Electrical grounding prong socket

    DOEpatents

    Leong, Robert

    1991-01-01

    The invention is a socket for a grounding prong used in a three prong electrical plug and a receptacle for the three prong plug. The socket being sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having a ridge to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket.

  8. The Effects of Longitudinal Control-System Dynamics on Pilot Opinion and Response Characteristics as Determined from Flight Tests and from Ground Simulator Studies

    NASA Technical Reports Server (NTRS)

    Sadoff, Melvin

    1958-01-01

    The results of a fixed-base simulator study of the effects of variable longitudinal control-system dynamics on pilot opinion are presented and compared with flight-test data. The control-system variables considered in this investigation included stick force per g, time constant, and dead-band, or stabilizer breakout force. In general, the fairly good correlation between flight and simulator results for two pilots demonstrates the validity of fixed-base simulator studies which are designed to complement and supplement flight studies and serve as a guide in control-system preliminary design. However, in the investigation of certain problem areas (e.g., sensitive control-system configurations associated with pilot- induced oscillations in flight), fixed-base simulator results did not predict the occurrence of an instability, although the pilots noted the system was extremely sensitive and unsatisfactory. If it is desired to predict pilot-induced-oscillation tendencies, tests in moving-base simulators may be required. It was found possible to represent the human pilot by a linear pilot analog for the tracking task assumed in the present study. The criterion used to adjust the pilot analog was the root-mean-square tracking error of one of the human pilots on the fixed-base simulator. Matching the tracking error of the pilot analog to that of the human pilot gave an approximation to the variation of human-pilot behavior over a range of control-system dynamics. Results of the pilot-analog study indicated that both for optimized control-system dynamics (for poor airplane dynamics) and for a region of good airplane dynamics, the pilot response characteristics are approximately the same.

  9. Practical Applications of Cosmic Ray Science: Spacecraft, Aircraft, Ground-Based Computation and Control Systems, Exploration, and Human Health and Safety

    NASA Technical Reports Server (NTRS)

    Koontz, Steve

    2015-01-01

    In this presentation a review of galactic cosmic ray (GCR) effects on microelectronic systems and human health and safety is given. The methods used to evaluate and mitigate unwanted cosmic ray effects in ground-based, atmospheric flight, and space flight environments are also reviewed. However not all GCR effects are undesirable. We will also briefly review how observation and analysis of GCR interactions with planetary atmospheres and surfaces and reveal important compositional and geophysical data on earth and elsewhere. About 1000 GCR particles enter every square meter of Earth’s upper atmosphere every second, roughly the same number striking every square meter of the International Space Station (ISS) and every other low- Earth orbit spacecraft. GCR particles are high energy ionized atomic nuclei (90% protons, 9% alpha particles, 1% heavier nuclei) traveling very close to the speed of light. The GCR particle flux is even higher in interplanetary space because the geomagnetic field provides some limited magnetic shielding. Collisions of GCR particles with atomic nuclei in planetary atmospheres and/or regolith as well as spacecraft materials produce nuclear reactions and energetic/highly penetrating secondary particle showers. Three twentieth century technology developments have driven an ongoing evolution of basic cosmic ray science into a set of practical engineering tools needed to design, test, and verify the safety and reliability of modern complex technological systems and assess effects on human health and safety effects. The key technology developments are: 1) high altitude commercial and military aircraft; 2) manned and unmanned spacecraft; and 3) increasingly complex and sensitive solid state micro-electronics systems. Space and geophysical exploration needs drove the development of the instruments and analytical tools needed to recover compositional and structural data from GCR induced nuclear reactions and secondary particle showers. Finally, the

  10. Ground truth versus no ground truth

    NASA Technical Reports Server (NTRS)

    Torbert, G. B.

    1970-01-01

    The area of study was the southeastern Arizona test site and three areas within the site were studied in detail: Safford, Point of Pines, and Fort Apache-White River. These areas have terrain contrast ranging from flat arid regions to high alpine mountains. Data were obtained from the Apollo 9 photographic missions, high altitude aerial photography, and simulated ERTS-A data from high altitude aircraft. Various monoscopic and steroscopic devices were used to analyze the features, and film density variations were studied. No ground-based data were permitted. Thematic maps were prepared for geology, geomorphology, vegetation, hydrology, and soils. Interpreted boundaries were delineated, with no collaborative data used in the interpretation. Ground-based data were gathered during the overflight of high altitude aerial photography. A further study was made using the ground truth, and the data gathered on the ground were compared with original mapping. 80% to 85% of the interpretations in the areas checked were correct. It was proved that it is possible to monitor gross features of the vigor of crop lands and vegetative cover, to type soils and classify geologic features, and to determine hydrologic conditions.

  11. TARDEC's Intelligent Ground Systems overview

    NASA Astrophysics Data System (ADS)

    Jaster, Jeffrey F.

    2009-05-01

    The mission of the Intelligent Ground Systems (IGS) Area at the Tank Automotive Research, Development and Engineering Center (TARDEC) is to conduct technology maturation and integration to increase Soldier robot control/interface intuitiveness and robotic ground system robustness, functionality and overall system effectiveness for the Future Combat System Brigade Combat Team, Robotics Systems Joint Project Office and game changing capabilities to be fielded beyond the current force. This is accomplished through technology component development focused on increasing unmanned ground vehicle autonomy, optimizing crew interfaces and mission planners that capture commanders' intent, integrating payloads that provide 360 degree local situational awareness and expanding current UGV tactical behavior, learning and adaptation capabilities. The integration of these technology components into ground vehicle demonstrators permits engineering evaluation, User assessment and performance characterization in increasingly complex, dynamic and relevant environments to include high speed on road or cross country operations, all weather/visibility conditions and military operations in urban terrain (MOUT). Focused testing and experimentation is directed at reducing PM risk areas (safe operations, autonomous maneuver, manned-unmanned collaboration) and transitioning technology in the form of hardware, software algorithms, test and performance data, as well as User feedback and lessons learned.

  12. Ground characterization for JAPE

    NASA Technical Reports Server (NTRS)

    Attenborough, Keith; Taherzadeh, Shahram

    1993-01-01

    Above-ground propagation modelling at the JAPE (Joint Acoustic Propagation Experiment) site requires a reasonably accurate model for the acoustical properties of the ground. Various models for the JAPE site are offered based on theoretical fits to short range data and to longer range data obtained with random noise and pure tones respectively from a loudspeaker under approximately quiescent isothermal conditions.

  13. Topographic controls on scaling of hydrologic and thermal processes in polygonal ground features of an Arctic ecosystem: A case study using idealized non-isothermal surface-subsurface simulations

    NASA Astrophysics Data System (ADS)

    Bisht, G.; Riley, W. J.; Collier, N.; Kumar, J.

    2014-12-01

    Arctic and sub-Arctic soils currently contain approximately 1700 billion metric tones of frozen organic carbon, approximately 200 times current annual anthropogenic emissions. This carbon is vulnerable to release to the atmosphere as CO2 and CH4 as high-latitude temperatures warm. Microtopographic features, such as polygonal ground, are characteristic sources of landscape heterogeneity in the Alaskan Arctic coastal plain. In a future warmer climate, the spatial distribution of soil moisture and active layer depth are expected to be key factors controlling the fate of thawed permafrost carbon. Polygonal ground structures, with high or low centers, dominate the local hydrologic environment, thereby impacting the energy balance, biogeochemical dynamics, vegetation communities, and carbon releases from the subsurface. In spite of their importance to local hydrologic and thermal processes, the impact of these microtopographic features at larger spatial scales is not well understood. Our previous work from isothermal surface-subsurface simulations has indicated that statistical moments of soil moisture follow a non-linear scaling relationship. In this study, we perform surface-subsurface non-isothermal flow simulations using PFLOTRAN for four study sites located near Barrow, AK. Simulations are performed on domains at multiple horizontal resolutions for several years. We describe the statistical moments of simulated soil moisture and soil temperature fields across spatial resolutions.

  14. Preventing and controlling land subsidence in Shanghai -towards more integrated and effective land use and ground water governance in the Yangtze Delta

    NASA Astrophysics Data System (ADS)

    Dai, Liping

    2016-04-01

    The Yangtze Delta, covers 210,700 square kilometers and with 156 million inhabitants (NRDC, 2010; The National Bureau of Statistics, 2011), is one of the areas most severely affected by land subsidence in China. Up to 2012, the area with cumulative subsidence above 200 mm in Yangtze Delta has been closed to 10,000 square kilometers. Shanghai, located at the estuary of the Yangtze River and with a population of 23 million, is the most densely populated city in Yangtze Delta (The National Bureau of Statistics, 2011). Since 1921, the recorded cumulative subsidence has been 200 to 300 mm in the central area of the city (Chai, Shen, Zhu, & Zhang, 2005). Excessive pumping of groundwater is considered to be the leading reason, accounts for nearly 70%, of the city's land subsidence, the weight of skyscrapers and global warming also play hefty roles (30%) (Springer, 2012). Research has shown that the main method to control land subsidence in Shanghai is to prevent groundwater from dropping (Chai, Shen, Zhu, & Zhang, 2005), the city has made great efforts in this regard since 1965 (the beginning of the so-called "control period"), for example, it has been recharging underground water through 121 wells with more than 60,000 tons every day since 2012 (Chinadaily, 2012). It is a huge burden considering the city has been suffering from a shortage of fresh water. In 2013, with the other two provinces of Jiangsu and Zhejiang in Yangtze Delta, Shanghai signed a delta cooperation agreement on the prevention and control of land subsidence and jointly issued a Prevention and Control Planning on Land Subsidence in Yangtze Delta (2014-2020), which aims to establish a long-effect mechanism in the delta scope. This research aims to analyze and assess the land and groundwater governance arrangements related to land subsidence in the Yangtze Delta in general and Shanghai in specific, in order to develop optimizing adaptation strategies and associated governance arrangements. It examines the

  15. Stochastic ground motion simulation

    USGS Publications Warehouse

    Rezaeian, Sanaz; Xiaodan, Sun

    2014-01-01

    Strong earthquake ground motion records are fundamental in engineering applications. Ground motion time series are used in response-history dynamic analysis of structural or geotechnical systems. In such analysis, the validity of predicted responses depends on the validity of the input excitations. Ground motion records are also used to develop ground motion prediction equations(GMPEs) for intensity measures such as spectral accelerations that are used in response-spectrum dynamic analysis. Despite the thousands of available strong ground motion records, there remains a shortage of records for large-magnitude earthquakes at short distances or in specific regions, as well as records that sample specific combinations of source, path, and site characteristics.

  16. Ground energy coupling

    NASA Astrophysics Data System (ADS)

    Metz, P. D.

    The feasibility of ground coupling for various heat pump systems was investigated. Analytical heat flow models were developed to approximate design ground coupling devices for use in solar heat pump space conditioning systems. A digital computer program called GROCS (GRound Coupled Systems) was written to model 3-dimensional underground heat flow in order to simulate the behavior of ground coupling experiments and to provide performance predictions which have been compared to experimental results. GROCS also has been integrated with TRNSYS. Soil thermal property and ground coupling device experiments are described. Buried tanks, serpentine earth coils in various configurations, lengths and depths, and sealed vertical wells are being investigated. An earth coil used to heat a house without use of resistance heating is described.

  17. 30 CFR 57.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Examination of ground conditions. 57.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Precautions-Surface and Underground § 57.3401 Examination of ground conditions....

  18. 30 CFR 57.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Examination of ground conditions. 57.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Precautions-Surface and Underground § 57.3401 Examination of ground conditions....

  19. 30 CFR 56.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Examination of ground conditions. 56.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control Precautions § 56.3401 Examination of ground conditions. Persons experienced in examining and testing for...

  20. 30 CFR 56.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Examination of ground conditions. 56.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control Precautions § 56.3401 Examination of ground conditions. Persons experienced in examining and testing for...

  1. 30 CFR 56.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Examination of ground conditions. 56.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control Precautions § 56.3401 Examination of ground conditions. Persons experienced in examining and testing for...

  2. 30 CFR 56.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Examination of ground conditions. 56.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control Precautions § 56.3401 Examination of ground conditions. Persons experienced in examining and testing for...

  3. 30 CFR 57.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Examination of ground conditions. 57.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Precautions-Surface and Underground § 57.3401 Examination of ground conditions....

  4. 30 CFR 57.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Examination of ground conditions. 57.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Precautions-Surface and Underground § 57.3401 Examination of ground conditions....

  5. 30 CFR 57.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Examination of ground conditions. 57.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Ground Control Precautions-Surface and Underground § 57.3401 Examination of ground conditions....

  6. 30 CFR 56.3401 - Examination of ground conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Examination of ground conditions. 56.3401... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control Precautions § 56.3401 Examination of ground conditions. Persons experienced in examining and testing for...

  7. Longevity of emplacement drift ground support materials

    SciTech Connect

    Tang, David

    2000-04-01

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for the selection of materials for ground support that will function throughout the preclosure period of a potential repository at Yucca Mountain. The Development Plan (DP) for this analysis is given in Longevity of Emplacement Drift Ground Support Materials (CRWMS M and O 1999a). The objective of this analysis is to update the previous analysis (CRWMS M and O 2000a) to account for related changes in the Ground Control System Description Document (CRWMS M and O 2000b), the Monitored Geologic Repository Project Description Document (CRWMS M and O 1999b), and in environmental conditions, and to provide updated information on candidate ground support materials.

  8. Area-wide ground applications of Bacillus thuringiensis var. israelensis for the control of Aedes albopictus in residential neighborhoods: from optimization to operation.

    PubMed

    Williams, Gregory M; Faraji, Ary; Unlu, Isik; Healy, Sean P; Farooq, Muhammad; Gaugler, Randy; Hamilton, George; Fonseca, Dina M

    2014-01-01

    The increasing range of Aedes albopictus, the Asian tiger mosquito, in the USA and the threat of chikungunya and dengue outbreaks vectored by this species have necessitated novel approaches to control this peridomestic mosquito. Conventional methods such as adulticiding provide temporary relief, but fail to manage this pest on a sustained basis. We explored the use of cold aerosol foggers and misting machines for area-wide applications of Bacillus thuringiensis var. israelensis (VectoBac WDG) as a larvicide targeting Aedes albopictus. During 2010-2013 we performed initially open field trials and then 19 operational area-wide applications in urban and suburban residential areas in northeastern USA to test three truck-mounted sprayers at two application rates. Area-wide applications of WDG in open field conditions at 400 and 800 g/ha killed on average 87% of tested larvae. Once techniques were optimized in residential areas, applications with a Buffalo Turbine Mist Sprayer at a rate of 800 g/ha, the best combination, consistently provided over 90% mortality. Importantly, there was no significant decrease in efficacy with distance from the spray line even in blocks of row homes with trees and bushes in the backyards. Under laboratory conditions Bti deposition in bioassay cups during the operational trials resulted in over 6 weeks of residual control. Our results demonstrate that area-wide truck mounted applications of WDG can effectively suppress Ae. albopictus larvae and should be used in integrated mosquito management approaches to control this nuisance pest and disease vector. PMID:25329314

  9. Area-Wide Ground Applications of Bacillus thuringiensis var. israelensis for the Control of Aedes albopictus in Residential Neighborhoods: From Optimization to Operation

    PubMed Central

    Williams, Gregory M.; Faraji, Ary; Unlu, Isik; Healy, Sean P.; Farooq, Muhammad; Gaugler, Randy; Hamilton, George; Fonseca, Dina M.

    2014-01-01

    The increasing range of Aedes albopictus, the Asian tiger mosquito, in the USA and the threat of chikungunya and dengue outbreaks vectored by this species have necessitated novel approaches to control this peridomestic mosquito. Conventional methods such as adulticiding provide temporary relief, but fail to manage this pest on a sustained basis. We explored the use of cold aerosol foggers and misting machines for area-wide applications of Bacillus thuringiensis var. israelensis (VectoBac WDG) as a larvicide targeting Aedes albopictus. During 2010–2013 we performed initially open field trials and then 19 operational area-wide applications in urban and suburban residential areas in northeastern USA to test three truck-mounted sprayers at two application rates. Area-wide applications of WDG in open field conditions at 400 and 800 g/ha killed on average 87% of tested larvae. Once techniques were optimized in residential areas, applications with a Buffalo Turbine Mist Sprayer at a rate of 800 g/ha, the best combination, consistently provided over 90% mortality. Importantly, there was no significant decrease in efficacy with distance from the spray line even in blocks of row homes with trees and bushes in the backyards. Under laboratory conditions Bti deposition in bioassay cups during the operational trials resulted in over 6 weeks of residual control. Our results demonstrate that area-wide truck mounted applications of WDG can effectively suppress Ae. albopictus larvae and should be used in integrated mosquito management approaches to control this nuisance pest and disease vector. PMID:25329314

  10. Lateral Stability and Control Characteristics of a Four-Propeller Deflected-Slipstream VTOL Model Including the Effects of Ground Proximity

    NASA Technical Reports Server (NTRS)

    Kuhn, Richard E.; Grunwald, Kalman J.

    1961-01-01

    The investigation of the lateral-directional stability and control characteristics of a four-propeller deflected-slipstream VTOL model in the transition speed range was conducted in the 17-foot test section of the Langley 300-MPH 7- by 10-foot tunnel. A large fairing on top of the rear fuselage was needed to eliminate directional instability in the power-off flaps-retracted condition. Even with this fairing some instability at small sideslip angles remained for power-on conditions with low flap deflections. The configuration exhibited a high level of dihedral effect which, coupled with the directional instability, will probably produce an undesirable Dutch roll oscillation.

  11. Measurement, characterization, and prediction of strong ground motion

    USGS Publications Warehouse

    Joyner, William; Boore, David M.

    1988-01-01

    A number of predictive relationships derived from regression analysis of strong-motion data are available for horizontal peak acceleration, velocity, and response spectral values. Theoretical prediction of ground motion calls for stochastic source models because source heterogeneities control the amplitude of ground motion at most, if not all, frequencies of engineering interest. Theoretical methods have been developed for estimation of ground-motion parameters and simulation of ground-motion time series. These methods are particularly helpful for regions such, as eastern North America where strong-motion data are sparse. The authors survey the field, first reviewing developments in ground-motion measurement and data processing. The authors then consider the choice of parameters for characterizing strong ground motion and describe the wave-types involved in strong ground motion and the factors affecting ground-motion amplitudes. They conclude by describing methods for predicting ground motion.

  12. Control of radiation and evaporation on temperature variability in a WRF regional climate simulation: comparison with colocated long term ground based observations near Paris

    NASA Astrophysics Data System (ADS)

    Bastin, S.; Chiriaco, M.; Drobinski, P.

    2016-03-01

    The objective of this paper is to understand how large-scale processes, cloud cover and surface fluxes affect the temperature variability over the SIRTA site, near Paris, and in a regional climate simulation performed in the frame of HyMeX/Med-CORDEX programs. This site is located in a climatic transitional area where models usually show strong dispersions despite the significant influence of large scale on interannual variability due to its western location. At seasonal time scale, the temperature is mainly controlled by surface fluxes. In the model, the transition from radiation to soil moisture limited regime occurs earlier than in observations leading to an overestimate of summertime temperature. An overestimate of shortwave radiation (SW), consistent with a lack of low clouds, enhances the soil dryness. A simulation with a wet soil is used to better analyse the relationship between dry soil and clouds but while the wetter soil leads to colder temperature, the cloud cover during daytime is not increased due to the atmospheric stability. At shorter time scales, the control of surface radiation becomes higher. In the simulation, higher temperatures are associated with higher SW. A wet soil mitigates the effect of radiation due to modulation by evaporation. In observations, the variability of clouds and their effect on SW is stronger leading to a nearly constant mean SW when sorted by temperature quantile but a stronger impact of cloud cover on day-to-day temperature variability. Impact of cloud albedo effect on precipitation is also compared.

  13. Experimental Test on Control Points Materialization for the Study of Vertical Movements of Soil and its Interactions with Ground Water Contents

    NASA Astrophysics Data System (ADS)

    Vittuari, L.; Gottardi, G.; Tini, M. A.

    2013-01-01

    In the study of soil vertical movements, one of the techniques most commonly used is the spirit levelling, now flanked by satellite SAR interferometry and by the analysis of time series acquired through permanent GNSS stations. The reliability of control points monuments varies depending both on the geological context and on the structure being representative of the investigated phenomenon. Often due to the high number of desired points or to the need of maintaining a specific areal distribution, they are fixed on existing structures (as in the common case of spirit levelling networks). This aspect is even more evident in the case of SAR interferometric analysis, where the permanent scatterers are identified on the basis of consistency in the radar response, but the points display movements measured by structures with different foundations at different depths. Starting from repeated precision levelling measurements, we verified which is the order of magnitude of movements of control points characterized by shallow foundations in cohesive soils, observing their behaviours at different depths, under simple and very common conditions such as the presence of periods of drought or rainfall. The results point-out movements in the order of 3-7 mm in the first meter of depth occurred in a week, during the transition between the period of summer drought and the first rains.

  14. METHOD OF LOCATING GROUNDS

    DOEpatents

    Macleish, K.G.

    1958-02-11

    ABS>This patent presents a method for locating a ground in a d-c circult having a number of parallel branches connected across a d-c source or generator. The complete method comprises the steps of locating the ground with reference to the mildpoint of the parallel branches by connecting a potentiometer across the terminals of the circuit and connecting the slider of the potentiometer to ground through a current indicating instrument, adjusting the slider to right or left of the mildpoint so as to cause the instrument to indicate zero, connecting the terminal of the network which is farthest from the ground as thus indicated by the potentiometer to ground through a condenser, impressing a ripple voltage on the circuit, and then measuring the ripple voltage at the midpoint of each parallel branch to find the branch in which is the lowest value of ripple voltage, and then measuring the distribution of the ripple voltage along this branch to determine the point at which the ripple voltage drops off to zero or substantially zero due to the existence of a ground. The invention has particular application where a circuit ground is present which will disappear if the normal circuit voltage is removed.

  15. Collaboration for Land, Air, Sea, and Space Vehicles: Developing the Common Ground in Vehicle Dynamics, System Identification, Control, and Handling Qualities

    NASA Astrophysics Data System (ADS)

    2002-11-01

    This technical report is the culmination of the SCI-053 Task Group - Vehicle Dynamics, System Identification, Control and Handling Qualities. It summarizes the discussions of tank, truck, aircraft, helicopter, ship, submarine and satellite experts held over a three-year period. It addresses the various technical areas identified in the name of the task group, exploring the similarities and differences between the vehicle types and identifying areas where collaboration between experts would be the most valuable. Twenty-three specific technical issues are identified as initial areas with high potential for valuable collaboration. Overall, the report provides the vehicle expert of one environment a sufficient background on the other vehicle environments, so that meaningful discussions towards these technical collaborations can be initiated.

  16. The Value of A Nuclear Ground Test

    SciTech Connect

    Blessing, David

    2006-07-01

    With limited budget for space exploration, it is important to look for ways to reduce the cost of the development of a space nuclear power system. One of the major contributors in cost estimates for such a development is the cost to conduct a nuclear ground test, which is an integrated test of the entire nuclear power system with the reactor providing nuclear power in a suitable test facility. Such a nuclear ground test would include the reactor, primary coolant system, shielding, power conversion, reactor instrumentation and control, power control electronics, and at least part of the flight heat rejection system. These components and systems will have been tested separately, but in the nuclear ground test they are tested together with heat supplied by the reactor for the first time. The unit tested would not be flown. This paper discusses the value of a nuclear ground test and identifies the specific test objectives that would be met in a nuclear ground test and the degree to which they could be met using an electrically heated integrated test. In the absence of a nuclear ground test, confidence in the system design can be increased by successful operation of units on the Moon or Mars. This paper comments on the ability of such operation to support validation of the design for manned missions. Finally this paper discusses features of a nuclear power system that would be particularly desirable to improve the chances that the flight unit will operate successfully if a nuclear ground test is not conducted. (author)

  17. Streamlining shuttle ground operations

    NASA Technical Reports Server (NTRS)

    Heimbold, R. L.; Reichert, W. H.

    1986-01-01

    To meet NASA Space Transportation System goals the Shuttle Processing Contractors have to reduce Space Transportation System ground processing time and ground processing costs. These objectives must be met without compromising safety of flight or safety during assembly, test, and service operations. Ground processing requirements are analyzed to determine critical serial flow paths and costly labor-intensive tasks. Processing improvements are realized by improvements in processing methodology, by application of computer-aided technology, and by modernization of KSC facilities. Ongoing improvement efforts are outlined and progress-to-date is described.

  18. Ground test experiment for large space structures

    NASA Technical Reports Server (NTRS)

    Tollison, D. K.; Waites, H. B.

    1985-01-01

    In recent years a new body of control theory has been developed for the design of control systems for Large Space Structures (LSS). The problems of testing this theory on LSS hardware are aggravated by the expense and risk of actual in orbit tests. Ground tests on large space structures can provide a proving ground for candidate control systems, but such tests require a unique facility for their execution. The current development of such a facility at the NASA Marshall Space Flight Center (MSFC) is the subject of this report.

  19. 14 CFR 27.395 - Control system.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... service use, including consideration of fatigue, jamming, ground gusts, control inertia, and friction... jamming, ground gusts, control inertia, or friction, the system must withstand the limit pilot...

  20. 14 CFR 27.395 - Control system.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... service use, including consideration of fatigue, jamming, ground gusts, control inertia, and friction... jamming, ground gusts, control inertia, or friction, the system must withstand the limit pilot...

  1. 14 CFR 27.395 - Control system.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... service use, including consideration of fatigue, jamming, ground gusts, control inertia, and friction... jamming, ground gusts, control inertia, or friction, the system must withstand the limit pilot...

  2. 14 CFR 27.395 - Control system.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... service use, including consideration of fatigue, jamming, ground gusts, control inertia, and friction... jamming, ground gusts, control inertia, or friction, the system must withstand the limit pilot...

  3. 14 CFR 27.395 - Control system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... service use, including consideration of fatigue, jamming, ground gusts, control inertia, and friction... jamming, ground gusts, control inertia, or friction, the system must withstand the limit pilot...

  4. Ground potential rise monitor

    DOEpatents

    Allen, Zachery Warren; Zevenbergen, Gary Allen

    2012-07-17

    A device and method for detecting ground potential rise (GPR) comprising a first electrode, a second electrode, and a voltage attenuator. The first electrode and the second electrode are both electrically connected to the voltage attenuator. A means for determining the presence of a dangerous ground potential is connected to the voltage attenuator. The device and method further comprises a means for enabling one or more alarms upon the detection of the dangerous ground potential. Preferably, a first transmitter/receiver is connected to the means for enabling one or more alarms. Preferably, a second transmitter/receiver, comprising a button, is electromagnetically connected to the first transmitter/receiver. Preferably, the means for determining the presence of a dangerous ground potential comprises a means for determining the true RMS voltage at the output of the voltage attenuator, a transient detector connected to the output of the voltage attenuator, or a combination thereof.

  5. Dynamic ground effects

    NASA Technical Reports Server (NTRS)

    Paulson, John W., Jr.; Kemmerly, Guy T.; Gilbert, William P.

    1990-01-01

    A research program is underway at the NASA Langley Research Center to study the effect of rate of descent on ground effects. A series of powered models were tested in the Vortex Research Facility under conditions with rate of descent and in the 14 x 22 Foot Subsonic Tunnel under identical conditions but without rate of descent. These results indicate that the rate of descent can have a significant impact on ground effects particularly if vectored or reversed thrust is used.

  6. Ground Water in Hawaii

    USGS Publications Warehouse

    Gingerich, Stephen B.; Oki, Delwyn S.

    2000-01-01

    Ground water is one of Hawaii's most important natural resources. It is used for drinking water, irrigation, and domestic, commercial, and industrial needs. Ground water provides about 99 percent of Hawaii's domestic water and about 50 percent of all freshwater used in the State. Total ground water pumped in Hawaii was about 500 million gallons per day during 1995, which is less than 3 percent of the average total rainfall (about 21 billion gallons per day) in Hawaii. From this perspective, the ground-water resource appears ample; however, much of the rainfall runs off to the ocean in streams or returns to the atmosphere by evapotranspiration. Furthermore, ground-water resources can be limited because of water-quality, environmental, or economic concerns. Water beneath the ground surface occurs in two principal zones: the unsaturated zone and the saturated zone. In the unsaturated zone, the pore spaces in rocks contain both air and water, whereas in the saturated zone, the pore spaces are filled with water. The upper surface of the saturated zone is referred to as the water table. Water below the water table is referred to as ground water. Ground-water salinity can range from freshwater to that of seawater. Freshwater is commonly considered to be water with a chloride concentration less than 250 mg/L, and this concentration represents about 1.3 percent of the chloride concentration of seawater (19,500 mg/L). Brackish water has a chloride concentration between that of freshwater (250 mg/L) and saltwater (19,500 mg/L).

  7. Residual shear strength variability as a primary control on movement of landslides reactivated by earthquake-induced ground motion: Implications for coastal Oregon, U.S.

    USGS Publications Warehouse

    Schulz, William H.; Wang, Gonghui

    2014-01-01

    Most large seismogenic landslides are reactivations of preexisting landslides with basal shear zones in the residual strength condition. Residual shear strength often varies during rapid displacement, but the response of residual shear zones to seismic loading is largely unknown. We used a ring shear apparatus to perform simulated seismic loading tests, constant displacement rate tests, and tests during which shear stress was gradually varied on specimens from two landslides to improve understanding of coseismic landslide reactivation and to identify shear strength models valid for slow gravitational failure through rapid coseismic failure. The landslides we studied represent many along the Oregon, U.S., coast. Seismic loading tests resulted in (1) catastrophic failure involving unbounded displacement when stresses represented those for the existing landslides and (2) limited to unbounded displacement when stresses represented those for hypothetical dormant landslides, suggesting that coseismic landslide reactivation may be significant during future great earthquakes occurring near the Oregon Coast. Constant displacement rate tests indicated that shear strength decreased exponentially during the first few decimeters of displacement but increased logarithmically with increasing displacement rate when sheared at 0.001 cm s−1 or greater. Dynamic shear resistance estimated from shear strength models correlated well with stresses observed during seismic loading tests, indicating that displacement rate and amount primarily controlled failure characteristics. We developed a stress-based approach to estimate coseismic landslide displacement that utilizes the variable shear strength model. The approach produced results that compared favorably to observations made during seismic loading tests, indicating its utility for application to landslides.

  8. Quantitative Campylobacter spp., antibiotic resistance genes, and veterinary antibiotics in surface and ground water following manure application: Influence of tile drainage control.

    PubMed

    Frey, Steven K; Topp, Edward; Khan, Izhar U H; Ball, Bonnie R; Edwards, Mark; Gottschall, Natalie; Sunohara, Mark; Lapen, David R

    2015-11-01

    This work investigated chlortetracycline, tylosin, and tetracycline (plus transformation products), and DNA-based quantitative Campylobacter spp. and Campylobacter tetracycline antibiotic resistant genes (tet(O)) in tile drainage, groundwater, and soil before and following a liquid swine manure (LSM) application on clay loam plots under controlled (CD) and free (FD) tile drainage. Chlortetracycline/tetracycline was strongly bound to manure solids while tylosin dominated in the liquid portion of manure. The chlortetracycline transformation product isochlortetracycline was the most persistent analyte in water. Rhodamine WT (RWT) tracer was mixed with manure and monitored in tile and groundwater. RWT and veterinary antibiotic (VA) concentrations were strongly correlated in water which supported the use of RWT as a surrogate tracer. While CD reduced tile discharge and eliminated application-induced VA movement (via tile) to surface water, total VA mass loading to surface water was not affected by CD. At both CD and FD test plots, the biggest 'flush' of VA mass and highest VA concentrations occurred in response to precipitation received 2d after application, which strongly influenced the flow abatement capacity of CD on account of highly elevated water levels in field initiating overflow drainage for CD systems (when water level <0.3m below surface). VA concentrations in tile and groundwater became very low within 10d following application. Both Campylobacter spp. and Campylobacter tet(O) genes were present in groundwater and soil prior to application, and increased thereafter. Unlike the VA compounds, Campylobacter spp. and Campylobacter tet(O) gene loadings in tile drainage were reduced by CD, in relation to FD. PMID:26065824

  9. Hanford site ground water protection management plan

    SciTech Connect

    Not Available

    1994-10-01

    Ground water protection at the Hanford Site consists of preventative and remedial measures that are implemented in compliance with a variety of environmental regulations at local, state, and federal levels. These measures seek to ensure that the resource can sustain a broad range of beneficial uses. To effectively coordinate and ensure compliance with applicable regulations, the U.S. Department of Energy has issued DOE Order 5400.1 (DOE 1988a). This order requires all U.S. Department of Energy facilities to prepare separate ground water protection program descriptions and plans. This document describes the Ground Water Protection Management Plan (GPMP) for the Hanford Site located in the state of Washington. DOE Order 5400.1 specifies that the GPMP covers the following general topical areas: (1) documentation of the ground water regime; (2) design and implementation of a ground water monitoring program to support resource management and comply with applicable laws and regulations; (3) a management program for ground water protection and remediation; (4) a summary and identification of areas that may be contaminated with hazardous waste; (5) strategies for controlling hazardous waste sources; (6) a remedial action program; and (7) decontamination, decommissioning, and related remedial action requirements. Many of the above elements are currently covered by existing programs at the Hanford Site; thus, one of the primary purposes of this document is to provide a framework for coordination of existing ground water protection activities. The GPMP provides the ground water protection policy and strategies for ground water protection/management at the Hanford Site, as well as an implementation plan to improve coordination of site ground water activities.

  10. Block ground interaction of rockfalls

    NASA Astrophysics Data System (ADS)

    Volkwein, Axel; Gerber, Werner; Kummer, Peter

    2016-04-01

    During a rockfall the interaction of the falling block with the ground is one of the most important factors that define the evolution of a rockfall trajectory. It steers the rebound, the rotational movement, possibly brake effects, friction losses and damping effects. Therefore, if most reliable rockfall /trajectory simulation software is sought a good understanding of the block ground interaction is necessary. Today's rockfall codes enable the simulation of a fully 3D modelled block within a full 3D surface . However, the details during the contact, i.e. the contact duration, the penetration depth or the dimension of the marks in the ground are usually not part of the simulation. Recent field tests with rocks between 20 and 80 kg have been conducted on a grassy slope in 2014 [1]. A special rockfall sensor [2] within the blocks measured the rotational velocity and the acting accelerations during the tests. External video records and a so-called LocalPositioningSystem deliver information on the travel velocity. With these data not only the flight phases of the trajectories but also the contacts with the ground can be analysed. During the single jumps of a block the flight time, jump length, the velocity, and the rotation are known. During the single impacts their duration and the acting accelerations are visible. Further, the changes of rotational and translational velocity influence the next jump of the block. The change of the rotational velocity over the whole trajectory nicely visualizes the different phases of a rockfall regarding general acceleration and deceleration in respect to the inclination and the topography of the field. References: [1] Volkwein A, Krummenacher B, Gerber W, Lardon J, Gees F, Brügger L, Ott T (2015) Repeated controlled rockfall trajectory testing. [Abstract] Geophys. Res. Abstr. 17: EGU2015-9779. [2] Volkwein A, Klette J (2014) Semi-Automatic Determination of Rockfall Trajectories. Sensors 14: 18187-18210.

  11. 46 CFR 120.376 - Grounded distribution systems (Neutral grounded).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ELECTRICAL INSTALLATION Power Sources and Distribution Systems § 120.376 Grounded distribution systems... ground, regardless of the number of power sources. This ground connection must be at the switchboard or at the common ground plate, which must be accessible. (b) Each propulsion, power, lighting,...

  12. Development requirements for a successful ground based CELSS demonstration

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Considerations critical to a ground based control demonstration were identified. The controlled ecological life support system technologies were assessed for nutrition and food processing, food production, waste processing, and systems engineering/modeling.

  13. Pollution of ground water in Europe

    PubMed Central

    Buchan, S.; Key, A.

    1956-01-01

    This paper discusses pollution of ground water in 20 countries of the European region, giving for each an account of the geology and hydrogeology, water supplies, the extent and nature of ground water pollution, and the legal, administrative, and technical means of controlling that pollution. For the countries not considered in the preceding article on surface water pollution, an account is also given of the superficial physical features, rainfall, population, and industries. A general discussion follows of such questions as the ways in which ground water pollution may occur, the factors mitigating or aggravating pollution, and ways of protection against pollution. The authors consider that the problem of ground water pollution in Europe may well be more serious than it would appear to be on the evidence so far obtained. PMID:13374533

  14. Space/ground systems as cooperating agents

    NASA Technical Reports Server (NTRS)

    Grant, T. J.

    1994-01-01

    Within NASA and the European Space Agency (ESA) it is agreed that autonomy is an important goal for the design of future spacecraft and that this requires on-board artificial intelligence. NASA emphasizes deep space and planetary rover missions, while ESA considers on-board autonomy as an enabling technology for missions that must cope with imperfect communications. ESA's attention is on the space/ground system. A major issue is the optimal distribution of intelligent functions within the space/ground system. This paper describes the multi-agent architecture for space/ground systems (MAASGS) which would enable this issue to be investigated. A MAASGS agent may model a complete spacecraft, a spacecraft subsystem or payload, a ground segment, a spacecraft control system, a human operator, or an environment. The MAASGS architecture has evolved through a series of prototypes. The paper recommends that the MAASGS architecture should be implemented in the operational Dutch Utilization Center.

  15. Ground Safety Issues

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, Paul D.

    2007-01-01

    In the history of humankind, every space adventure, great or small, has begun on the ground. While this seems to be stating the obvious, mission and flight hardware designers who have overlooked this fact have paid a high price, either in loss or damage to the hardware pre-launch, or in mission failure or reduction. Designers may risk not only their flight hardware, but they may also risk their lives, their co-workers lives and even the general public by not heeding safety on the ground. Their eyes may be on the stars but their feet are on the ground! This discussion applies to all forms of flight hardware from the largest rockets to the smallest spare parts.

  16. Low cost satellite transportable Ground Station

    NASA Astrophysics Data System (ADS)

    Laufman, G. E.; Slivkoff, W. J.

    A low cost Transportable Ground Station (TGS) for satellite tracking, telemetry and control (TTC) applications is described. The initial focus of the TGS is to provide S-band space-ground-link-subsystem TTC services for these satellites with compatible transponders. The TGS also has the capability to be expanded to perform mission control station tasks including telemetry data analysis, command formulation, mission analysis and satellite ephemeris generation. The TGS consists of a shelter and a folded 5-m antenna both of which are mounted on a commercial air ride trailer. The TGS size meets requirements for United States highway transportation. The TGS can also be transported via C-130 aircraft.

  17. Monitoring for pesticides in ground water in Nevada

    USGS Publications Warehouse

    Adams, Patricia A.; Moses, Charles W.; Bevans, Hugh E.

    1997-01-01

    Many pesticides designed to control weed encroachment, plant disease, and insect predation are used in agricultural and urban areas in the United States. Contamination of ground water by pesticides has increased over the last 20 years (U.S. Environmental Protection Agency, 1992). In 1985, the U.S. Environmental Protection Agency (USEPA) estimated the detection of at least 17 agricultural pesticides in the ground water of 23 states. By 1988, pesticides identified in ground water had increased to 46 in 26 states. To protect ground water from pesticide contamination, USEPA, through the Federal Fungicide Insecticide and Rodenticide Act (FIFRA), requires all states to institute a ground-water protection program.

  18. Artificial supports for coal mine ground control

    SciTech Connect

    1996-12-31

    The report is a discussion of four types of support systems developed by the U.S. Bureau of Mines for use in both room-and-pillar retreat and longwall mining systems. These are: Mobile Roof Support System; Steel-Fiber-Reinforced Concrete Cribbing; Yielding Steel Posts; and Lightweight Hydraulic Supports.

  19. Remote Operations and Ground Control Centers

    NASA Technical Reports Server (NTRS)

    Bryant, Barry S.; Lankford, Kimberly; Pitts, R. Lee

    2004-01-01

    The Payload Operations Integration Center (POIC) at the Marshall Space Flight Center supports the International Space Station (ISS) through remote interfaces around the world. The POIC was originally designed as a gateway to space for remote facilities; ranging from an individual user to a full-scale multiuser environment. This achievement was accomplished while meeting program requirements and accommodating the injection of modern technology on an ongoing basis to ensure cost effective operations. This paper will discuss the open POIC architecture developed to support similar and dissimilar remote operations centers. It will include technologies, protocols, and compromises which on a day to day basis support ongoing operations. Additional areas covered include centralized management of shared resources and methods utilized to provide highly available and restricted resources to remote users. Finally, the effort of coordinating the actions of participants will be discussed.

  20. The grounding of temporal metaphors.

    PubMed

    Lai, Vicky T; Desai, Rutvik H

    2016-03-01

    Grounded cognition suggests that the processing of conceptual knowledge cued by language relies on the sensory-motor regions. Does temporal language similarly engage brain areas involved in time perception? Participants read sentences that describe the temporal extent of events with motion verbs (The hours crawled until the release of the news) and their static controls. Comparison conditions were fictive motion (The trail crawled until the end of the hills) and literal motion (The caterpillar crawled towards the top of the tree), along with their static controls. Several time sensitive locations, identified using a meta-analysis, showed activation specific to temporal metaphors, including in the left insula, right claustrum, and bilateral posterior superior temporal sulci. Fictive and literal motion contrasts did not show this difference. Fictive motion contrast showed activation in a conceptual motion sensitive area of the left posterior inferior temporal sulcus (ITS). These data suggest that language of time is at least partially grounded in experiential time. In addition, motion semantics has different consequences for events and objects: temporal events become animate, while static entities become motional. PMID:26854961

  1. THEMIS Ground-based Magnetometers

    NASA Astrophysics Data System (ADS)

    Pierce, D.; Means, J. D.; Dearborn, D.; Russell, C. T.; Strangeway, R. J.; Mende, S.; Craig, N.; Angelopoulos, V.

    2004-05-01

    This paper describes the design and development of a fluxgate suitable for full earth's field ground measurements and to be used for the ground-based segment of the THEMIS project.. The operation of the electronics is based on a 2nd order sigma-delta technique that yields a 24 bit/axis vector value with 4ppm measurement resolution at 2Hz without the use of analog to digital converters. This digital design produces superior noise performance over more conventional techniques while dramatically increasing the resolution of the magnetic field measurement. The magnetometer system is equipped with a DAC offsetting system which by program control can offset the Earth's field in any sensor orientation. Time and position data are maintained to an accuracy of 100usec and 40 meters with a dedicated Trimble Acutime2000 GPS receiver. The magnetometer may be powered from any un-regulated DC source capable of delivering 300ma. @ +10-24VDC. All data are output via USB or RS-232 interface to LabView host software which has been developed to support either Windows or Linux operating systems.Interrogation and control of the magnetometer is available via TCP protocol through a host internet connection.

  2. Coding Issues in Grounded Theory

    ERIC Educational Resources Information Center

    Moghaddam, Alireza

    2006-01-01

    This paper discusses grounded theory as one of the qualitative research designs. It describes how grounded theory generates from data. Three phases of grounded theory--open coding, axial coding, and selective coding--are discussed, along with some of the issues which are the source of debate among grounded theorists, especially between its…

  3. Storage tanks: Going above ground

    SciTech Connect

    Wilson, T.C. )

    1994-03-01

    This article examines the trend toward above ground storage tanks for petroleum products and certain hazardous substances. The topics of the article include the advantages and disadvantages of above ground storage tanks, regulations for use of above ground storage tanks, design options, safety issues, and a description of typical users of above ground storage tanks.

  4. Echoes at Ground Zero

    ERIC Educational Resources Information Center

    Chronicle of Higher Education, 2006

    2006-01-01

    An excerpt from the opening piece in "Everything That Rises: A Book of Convergences" by Lawrence Weschler is presented where the author is talking with Joel Meyerowitz, the only photographer granted unimpeded access to the clean-up operations at ground zero after the terrorist attacks of September 11, 2001. The two discuss the parallels between…

  5. Technology at Ground Zero.

    ERIC Educational Resources Information Center

    Techniques: Connecting Education and Careers, 2002

    2002-01-01

    Describes the robots used to aid in rescue and recovery at Ground Zero after the September 11, 2001 attack on the World Trade Center. The robots were developed as a result of national Science Foundation Quick Response Research Awards. Describes several awards that were made following the attack. (JOW)

  6. Four frequency ground scatterometer

    NASA Technical Reports Server (NTRS)

    Dickerson, E. T.

    1982-01-01

    The FM-CW Radar, used as a microwave scatterometer is described. Scatterometer system design, scatterometer system calibration, parameter calculation and correction for data acquisition, ground scatterometer data acquistion at Jornada Experimental Range, and Kansas radar cross-calibration test are discussed.

  7. Informed Grounded Theory

    ERIC Educational Resources Information Center

    Thornberg, Robert

    2012-01-01

    There is a widespread idea that in grounded theory (GT) research, the researcher has to delay the literature review until the end of the analysis to avoid contamination--a dictum that might turn educational researchers away from GT. Nevertheless, in this article the author (a) problematizes the dictum of delaying a literature review in classic…

  8. Korea's School Grounds Projects

    ERIC Educational Resources Information Center

    Park, Joohun

    2003-01-01

    This article describes two projects which Korea has undertaken to improve its school grounds: (1) the Green School Project; and (2) the School Forest Pilot Project. The Korean Ministry of Education and Human Resources Development (MOE&HRI) recently launched the Green School Project centred on existing urban schools with poor outdoor environments.…

  9. Grounding in Instant Messaging

    ERIC Educational Resources Information Center

    Fox Tree, Jean E.; Mayer, Sarah A.; Betts, Teresa E.

    2011-01-01

    In two experiments, we investigated predictions of the "collaborative theory of language use" (Clark, 1996) as applied to instant messaging (IM). This theory describes how the presence and absence of different grounding constraints causes people to interact differently across different communicative media (Clark & Brennan, 1991). In Study 1, we…

  10. Ground-coupled heat pump demonstration

    SciTech Connect

    O'Connell, T.

    1983-09-01

    This report presents the results of a field evaluation of an innovative ground-coupled heat pump system which features a unique collector design and system control strategy aimed at maximizing heat pump performance by minimizing ground temperature change. The collector design includes several short closed loops, each consisting of a pair of polyethylene pipes buried 12 to 18 inches apart in a horizontal trench approximately six feet below ground. A micropressor is used to control flow and optimize system operation. Extrapolation of the results of experiments conducted on a unit length (250 ft.) of collector field during the 1981-82 and 1982-83 heating seasons indicates that a system seasonal performance factor of 2.75 to 3.0 will be achievable in practice.

  11. 14 CFR 121.421 - Flight attendants: Initial and transition ground training.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ground training. 121.421 Section 121.421 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... § 121.421 Flight attendants: Initial and transition ground training. (a) Initial and transition ground... equipment and the controls for cabin heat and ventilation. (b) Initial and transition ground training...

  12. 14 CFR 121.421 - Flight attendants: Initial and transition ground training.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ground training. 121.421 Section 121.421 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... § 121.421 Flight attendants: Initial and transition ground training. (a) Initial and transition ground... equipment and the controls for cabin heat and ventilation. (b) Initial and transition ground training...

  13. 14 CFR 121.421 - Flight attendants: Initial and transition ground training.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... ground training. 121.421 Section 121.421 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... § 121.421 Flight attendants: Initial and transition ground training. (a) Initial and transition ground... equipment and the controls for cabin heat and ventilation. (b) Initial and transition ground training...

  14. 14 CFR 121.421 - Flight attendants: Initial and transition ground training.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ground training. 121.421 Section 121.421 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... § 121.421 Flight attendants: Initial and transition ground training. (a) Initial and transition ground... equipment and the controls for cabin heat and ventilation. (b) Initial and transition ground training...

  15. FBM Ground Segment and Operations Concept

    NASA Astrophysics Data System (ADS)

    Cardoso, P.; Gonçalves, L.; Ambrósio, A.; Carvalho, H.

    The French-Brazilian Micro-satellite (FBM) Mission is a cooperative program between the French Space Agency ("Centre National d`Estudes Spatiales" - CNES - France) and the National Institute for Space Research (INPE - Brazil). This mission consists in developing, launching, and controlling a scientific/technologic micro-satellite as well as the payload data dissemination. Five Brazilian and four French technological and scientific experiments will fly onboard the FBM. The task division among INPE and CNES is as follows: INPE is responsible for the Satellite System, Power Supply, Structure and Thermal Control Subsystem, Ground Segment and Operations. CNES provides the AOCS, TT&C and OBDH Subsystems. This paper presents the Ground Segment architecture, and describes its development process, along with the Mission Operations Concept, adopted for the joint program. The Ground Segment is being developed under the directive of maximum re-use of existing systems in Brazil, and the constraints imposed by the Command &Control Interface Specifications; Ground to Board Interface Definition applicable to the subsystems provided by CNES. In addition, a maximum commonality between processes and elements of AIT and operations (Control Center/Ground Station) was sought for risk and costs reduction reasons. Mission Operations were conceived as a trade-off between operational autonomy of the satellite and ground segment, and a fast reaction under contingency situations foreseen for the scientific payload equipment. Scheduled to be launched by early 2004, FBM aims at being a valuable tool for both the French and Brazilian scientific and technological communities, and provides a rich framework of technical cooperation between both countries.

  16. Ground vortex flow field investigation

    NASA Technical Reports Server (NTRS)

    Kuhn, Richard E.; Delfrate, John H.; Eshleman, James E.

    1988-01-01

    Flow field investigations were conducted at the NASA Ames-Dryden Flow Visualization Facility (water tunnel) to investigate the ground effect produced by the impingement of jets from aircraft nozzles on a ground board in a STOL operation. Effects on the overall flow field with both a stationary and a moving ground board were photographed and compared with similar data found in other references. Nozzle jet impingement angles, nozzle and inlet interaction, side-by-side nozzles, nozzles in tandem, and nozzles and inlets mounted on a flat plate model were investigated. Results show that the wall jet that generates the ground effect is unsteady and the boundary between the ground vortex flow field and the free-stream flow is unsteady. Additionally, the forward projection of the ground vortex flow field with a moving ground board is one-third less than that measured over a fixed ground board. Results also showed that inlets did not alter the ground vortex flow field.

  17. Longevity of Emplacement Drift Ground Support Materials

    SciTech Connect

    D. Tang

    2000-01-07

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for selection of materials for ground support that will function throughout the preclosure period. The Development Plan (DP) for this analysis is given in CRWMS M&O (Civilian Radioactive Waste Management System Management and Operating Contractor) (1999a). The candidate materials for ground support are steel (carbon steel, ductile cast iron, galvanized steel, and stainless steel, etc.) and cement. Steel will mainly be used for steel sets, lagging, channels, rock bolts, and wire mesh. Cement usage is only considered in the case of grouted rock bolts. The candidate materials for the invert structure are steel and crushed rock ballast. The materials shall be evaluated for the repository emplacement drift environment under a specific thermal loading condition based on the proposed License Application Design Selection (LADS) design. The analysis consists of the following tasks: (1) Identify factors affecting the longevity of ground control materials for use in emplacement drifts. (2) Review existing documents concerning behavior of candidate ground control materials during the preclosure period. The major criteria to be considered for steel are mechanical and thermal properties, and durability, of which corrosion is the most important concern. (3) Evaluate the available results and develop recommendations for material(s) to be used.

  18. Goddard Ground System Environment

    NASA Technical Reports Server (NTRS)

    Liu, Ben

    2009-01-01

    This slide presentation reviews the Goddard Mission Services Evolution Center's work in providing the Ground System Infrastructure to allow for standard interfaces, and allow for a mix of heritage and new components. This software has been used by NASA and other Government users. Telemetry and command services are also provided as are mission planning and scheduling systems. Other areas that the presentation covers are work on trending systems, and data management system.

  19. Grounded spatial belief revision.

    PubMed

    Nejasmic, Jelica; Bucher, Leandra; Knauff, Markus

    2015-05-01

    Beliefs frequently undergo revisions, especially when new pieces of information are true but inconsistent with current beliefs. In previous studies, we showed that linguistic asymmetries provided by relational statements, play a crucial role in spatial belief revision. Located objects (LO) are preferably revised compared to reference objects (RO), known as the LO-principle. Here we establish a connection between spatial belief revision and grounded cognition. In three experiments, we explored whether imagined physical object properties influence which object is relocated and which remains at its initial position. Participants mentally revised beliefs about the arrangements of objects which could be envisaged as light and heavy (Experiment 1), small and large (Experiment 2), or movable and immovable (Experiment 3). The results show that intrinsic object properties are differently taken into account during spatial belief revision. Object weight did not alter the LO-principle (Experiment 1), whereas object size was found to influence which object was preferably relocated (Experiment 2). Object movability did not affect relocation preferences but had an effect on relocation durations (Experiment 3). The findings support the simulation hypothesis within the grounded cognition approach and create new connections between the spatial mental model theory of reasoning and the idea of grounded cognition. PMID:25796056

  20. The LOFT ground segment

    NASA Astrophysics Data System (ADS)

    Bozzo, E.; Antonelli, A.; Argan, A.; Barret, D.; Binko, Pavel; Brandt, S.; Cavazzuti, E.; Courvoisier, T.; den Herder, J. W.; Feroci, M.; Ferrigno, C.; Giommi, P.; Götz, D.; Guy, L.; Hernanz, M.; in't Zand, J. J. M.; Klochkov, D.; Kuulkers, Erik; Motch, C.; Lumb, D.; Papitto, A.; Pittori, Carlotta; Rohlfs, R.; Santangelo, A.; Schmid, C.; Schwope, A. D.; Smith, P. J.; Webb, N. A.; Wilms, J.; Zane, S.

    2014-07-01

    LOFT, the Large Observatory For X-ray Timing, was one of the ESA M3 mission candidates that completed their assessment phase at the end of 2013. LOFT is equipped with two instruments, the Large Area Detector (LAD) and the Wide Field Monitor (WFM). The LAD performs pointed observations of several targets per orbit (~90 minutes), providing roughly ~80 GB of proprietary data per day (the proprietary period will be 12 months). The WFM continuously monitors about 1/3 of the sky at a time and provides data for about ~100 sources a day, resulting in a total of ~20 GB of additional telemetry. The LOFT Burst alert System additionally identifies on-board bright impulsive events (e.g., Gamma-ray Bursts, GRBs) and broadcasts the corresponding position and trigger time to the ground using a dedicated system of ~15 VHF receivers. All WFM data are planned to be made public immediately. In this contribution we summarize the planned organization of the LOFT ground segment (GS), as established in the mission Yellow Book1. We describe the expected GS contributions from ESA and the LOFT consortium. A review is provided of the planned LOFT data products and the details of the data flow, archiving and distribution. Despite LOFT was not selected for launch within the M3 call, its long assessment phase ( >2 years) led to a very solid mission design and an efficient planning of its ground operations.

  1. 50. Ground floor, looking northwest at former location of ground ...

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

    50. Ground floor, looking northwest at former location of ground floor (bottom) level of milk room - Sheffield Farms Milk Plant, 1075 Webster Avenue (southwest corner of 166th Street), Bronx, Bronx County, NY

  2. Chapter IV - Safety During Payload Ground Processing

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, Paul; Dollberg, John; Trinchero, Jean-Pierre

    2012-01-01

    This chapter describes the typical hazards that can be expected to be encountered when processing payloads on the ground. Also described are some of the more common controls for these hazards. Many of these controls are based on hard requirements but they are also based on specific lessons learned. This chapter uses the term Flight Hardware (F/H) for all payloads regardless of size.

  3. Modular approach for satellite communication ground terminals

    NASA Astrophysics Data System (ADS)

    Gould, G. R.

    Attention is given to a novel approach to the design and construction of ground terminals which encompasses a programmable timing generation concept, a flexible memory unit design, and variable speed serial-parallel/parallel-serial converters that will meet the various ground terminal operational requirements. These requirements include coherent phase shift and trunking terminals, and may be expanded to incorporate Demand Assignment Multiple Access and Network Control. Other design approaches are examined which employ single function, fixed timing subassemblies dedicated to the execution of specific functions. The use of multifunction units is, however, more cost effective from the viewpoints of production and maintainability.

  4. Procedures for ground-water investigations. Revision 1

    SciTech Connect

    Not Available

    1992-12-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water monitoring procedures are developed and used in accordance with the PNL Quality Assurance Program.

  5. In-Situ Use of Ground Water By Alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A replicated column lysimeter study was conducted over a 4 year period to determine the effect of groundwater salinity and depth to ground water on the in-situ use of groundwater by a salt tolerant alfalfa crop. The treatments included a control with no groundwater, and ground water with electrical ...

  6. CONNECTICUT GROUND WATER QUALITY CLASSIFICATIONS

    EPA Science Inventory

    This is a 1:24,000-scale datalayer of Ground Water Quality Classifications in Connecticut. It is a polygon Shapefile that includes polygons for GA, GAA, GAAs, GB, GC and other related ground water quality classes. Each polygon is assigned a ground water quality class, which is s...

  7. Predicting Ground Illuminance

    NASA Astrophysics Data System (ADS)

    Lesniak, Michael V.; Tregoning, Brett D.; Hitchens, Alexandra E.

    2015-01-01

    Our Sun outputs 3.85 x 1026 W of radiation, of which roughly 37% is in the visible band. It is directly responsible for nearly all natural illuminance experienced on Earth's surface, either in the form of direct/refracted sunlight or in reflected light bouncing off the surfaces and/or atmospheres of our Moon and the visible planets. Ground illuminance, defined as the amount of visible light intercepting a unit area of surface (from all incident angles), varies over 7 orders of magnitude from day to night. It is highly dependent on well-modeled factors such as the relative positions of the Sun, Earth, and Moon. It is also dependent on less predictable factors such as local atmospheric conditions and weather.Several models have been proposed to predict ground illuminance, including Brown (1952) and Shapiro (1982, 1987). The Brown model is a set of empirical data collected from observation points around the world that has been reduced to a smooth fit of illuminance against a single variable, solar altitude. It provides limited applicability to the Moon and for cloudy conditions via multiplicative reduction factors. The Shapiro model is a theoretical model that treats the atmosphere as a three layer system of light reflectance and transmittance. It has different sets of reflectance and transmittance coefficients for various cloud types.In this paper we compare the models' predictions to ground illuminance data from an observing run at the White Sands missile range (data was obtained from the United Kingdom's Meteorology Office). Continuous illuminance readings were recorded under various cloud conditions, during both daytime and nighttime hours. We find that under clear skies, the Shapiro model tends to better fit the observations during daytime hours with typical discrepancies under 10%. Under cloudy skies, both models tend to poorly predict ground illuminance. However, the Shapiro model, with typical average daytime discrepancies of 25% or less in many cases

  8. GRC Ground Support Facilities

    NASA Technical Reports Server (NTRS)

    SaintOnge, Thomas H.

    2010-01-01

    The ISS Program is conducting an "ISS Research Academy' at JSC the first week of August 2010. This Academy will be a tutorial for new Users of the International Space Station, focused primarily on the new ISS National Laboratory and its members including Non-Profit Organizations, other government agencies and commercial users. Presentations on the on-orbit research facilities accommodations and capabilities will be made, as well as ground based hardware development, integration and test facilities and capabilities. This presentation describes the GRC Hardware development, test and laboratory facilities.

  9. Fuel control

    SciTech Connect

    Charrier, M.G.

    1986-08-19

    This patent describes a gas turbine engine control which responds to a compressor discharge pressure (CDP) and a compressor bleed pressure (CBP). The improvement described here consists of: (a) sensing means for sensing whether the aircraft is on the ground and (b) means coupled to the sensing means for artificially increasing the ratio of CBP/CDP which is sensed by the control, during engine startup, while the aircraft is on the ground.

  10. 40 CFR 144.87 - How does the identification of ground water protection areas and other sensitive ground water...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false How does the identification of ground water protection areas and other sensitive ground water areas affect me? 144.87 Section 144.87 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM Requirements...

  11. 40 CFR 144.87 - How does the identification of ground water protection areas and other sensitive ground water...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false How does the identification of ground water protection areas and other sensitive ground water areas affect me? 144.87 Section 144.87 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM Requirements...

  12. Ground based infrared astronomy

    NASA Technical Reports Server (NTRS)

    Jennings, D. E.

    1988-01-01

    Infrared spectroscopic instrumentation has been developed for ground-based measurements of astrophysical objects in the intermediate infrared. A conventional Michelson interferometer is limited for astronomical applications in the intermediate infrared by quantum noise fluctuations in the radiation form the source and/or background incident on the detector, and the multiplex advantage is no longer available. One feasible approach to recovering the multiplex advantage is post-dispersion. The infrared signal after passing through telescope and interferometer, is dispersed by a low resolution grating spectrometer onto an array of detectors. The feasibility of the post-dispersion system has been demonstrated with observations of astrophysical objects in the 5 and 10 micrometer atmospheric windows from ground-based telescopes. During FY87/88 the post-disperser was used at the Kitt Peak 4-meter telescope and McMath telescope with facility Fourier transform spectrometers. Jupiter, Saturn, Mars, and Venus were observed. On Jupiter, the resolution at 12 micrometer was 0.01/cm, considerably higher than had been acheived previously. The spectrum contains Jovian ethane and acetylene emission. Construction was begun on the large cryogenic grating spectrometer.

  13. A thermal ground cloak

    NASA Astrophysics Data System (ADS)

    Yang, Tianzhi; Wu, Qinghe; Xu, Weikai; Liu, Di; Huang, Lujun; Chen, Fei

    2016-02-01

    The thermal cloak has been a long-standing scientific dream of researchers and engineers. Recently thermal metamaterials with man-made micro-structure have been presented based on the principle of transformation optics (TO). This new concept has received considerable attention, which is a powerful tool for manipulating heat flux in thermal imaging systems. However, the inherent material singularity has long been a captivation of experimental realization. As an alternative method, the scattering-cancellation-based cloak (or bi-layer thermal cloak) has been presented to remove the singularity for achieving the same cloaking performance. Nevertheless, such strategy needs prerequisite knowledge (geometry and conductivity) of the object to be cloaked. In this paper, a new thermal ground cloak is presented to overcome the limitations. The device is designed, fabricated and measured to verify the thermal cloaking performance. We experimentally show that the remarkably low complexity of the device can fully and effectively be manipulated using realizable transformation thermal devices. More importantly, this thermal ground cloak is designed to exclude heat flux without knowing the information of the cloaked object.

  14. Ground water and energy

    SciTech Connect

    Not Available

    1980-05-01

    In view of complex environmental/energy decisions, the Environmental Impacts Division of the Office of Technology Impacts develops analytical methods for conducting policy analyses supporting decision making. The methods development process often begins with a workshop of leading experts and specialists in the relevant disciplines and issue areas; workshop findings are subsequently utilized by OTI to form a more solid foundation for viable policies. The National Workshop on Ground Water and Energy Production was envisioned as a tool through which OTI could obtain insights, information, and methods (on environmental, economical, physical, political, legal, and social issues) to use in its analyses, models, and assessments. To accomplish this, the Workshop comprised both plenary sessions and individual working groups. The former provided opportunities for all participants to explore issues from a broad perspective, whereas the latter enabled participants to focus on the three following areas: ground water supply; conflicts and barriers to its use; and alternatives or solutions to the various issues. This report summarizes information and insights gained by the Office of Technology Impacts during the course of the Workshop. The Key Findings section summarizes the most important facts discovered during the Workshop. The three general topics that follow (Supply, Conflicts and Barriers, and Alternatives) are those described in the Core Issues statements. The statements are reflective of the recommendations and analyses prepared by the several working groups.

  15. Ground Motion Prediction Equations Empowered by Stress Drop Measurement

    NASA Astrophysics Data System (ADS)

    Miyake, H.; Oth, A.

    2015-12-01

    Significant variation of stress drop is a crucial issue for ground motion prediction equations and probabilistic seismic hazard assessment, since only a few ground motion prediction equations take into account stress drop. In addition to average and sigma studies of stress drop and ground motion prediction equations (e.g., Cotton et al., 2013; Baltay and Hanks, 2014), we explore 1-to-1 relationship for each earthquake between stress drop and between-event residual of a ground motion prediction equation. We used the stress drop dataset of Oth (2013) for Japanese crustal earthquakes ranging 0.1 to 100 MPa and K-NET/KiK-net ground motion dataset against for several ground motion prediction equations with volcanic front treatment. Between-event residuals for ground accelerations and velocities are generally coincident with stress drop, as investigated by seismic intensity measures of Oth et al. (2015). Moreover, we found faster attenuation of ground acceleration and velocities for large stress drop events for the similar fault distance range and focal depth. It may suggest an alternative parameterization of stress drop to control attenuation distance rate for ground motion prediction equations. We also investigate 1-to-1 relationship and sigma for regional/national-scale stress drop variation and current national-scale ground motion equations.

  16. Cavity optomechanics -- beyond the ground state

    NASA Astrophysics Data System (ADS)

    Meystre, Pierre

    2011-05-01

    The coupling of coherent optical systems to micromechanical devices, combined with breakthroughs in nanofabrication and in ultracold science, has opened up the exciting new field of cavity optomechanics. Cooling of the vibrational motion of a broad range on oscillating cantilevers and mirrors near their ground state has been demonstrated, and the ground state of at least one such system has now been reached. Cavity optomechanics offers much promise in addressing fundamental physics questions and in applications such as the detection of feeble forces and fields, or the coherent control of AMO systems and of nanoscale electromechanical devices. However, these applications require taking cavity optomechanics ``beyond the ground state.'' This includes the generation and detection of squeezed and other non-classical states, the transfer of squeezing between electromagnetic fields and motional quadratures, and the development of measurement schemes for the characterization of nanomechanical structures. The talk will present recent ``beyond ground state'' developments in cavity optomechanics. We will show how the magnetic coupling between a mechanical membrane and a BEC - or between a mechanical tuning fork and a nanoscale cantilever - permits to control and monitor the center-of-mass position of the mechanical system, and will comment on the measurement back-action on the membrane motion. We will also discuss of state transfer between optical and microwave fields and micromechanical devices. Work done in collaboration with Dan Goldbaum, Greg Phelps, Keith Schwab, Swati Singh, Steve Steinke, Mehmet Tesgin, and Mukund Vengallatore and supported by ARO, DARPA, NSF, and ONR.

  17. Automated Ground Umbilical Systems (AGUS) Project

    NASA Technical Reports Server (NTRS)

    Gosselin, Armand M.

    2007-01-01

    All space vehicles require ground umbilical systems for servicing. Servicing requirements can include, but are not limited to, electrical power and control, propellant loading and venting, pneumatic system supply, hazard gas detection and purging as well as systems checkout capabilities. Of the various types of umbilicals, all require several common subsystems. These typically include an alignment system, mating and locking system, fluid connectors, electrical connectors and control !checkout systems. These systems have been designed to various levels of detail based on the needs for manual and/or automation requirements. The Automated Ground Umbilical Systems (AGUS) project is a multi-phase initiative to develop design performance requirements and concepts for launch system umbilicals. The automation aspect minimizes operational time and labor in ground umbilical processing while maintaining reliability. This current phase of the project reviews the design, development, testing and operations of ground umbilicals built for the Saturn, Shuttle, X-33 and Atlas V programs. Based on the design and operations lessons learned from these systems, umbilicals can be optimized for specific applications. The product of this study is a document containing details of existing systems and requirements for future automated umbilical systems with emphasis on design-for-operations (DFO).

  18. Predicting Ground Illuminance

    NASA Astrophysics Data System (ADS)

    Lesniak, Michael V.

    2014-01-01

    Our Sun outputs 3.85 × 1026 W of radiation, of which ≈37% is in the visible band. It is directly responsible for nearly all natural illuminance experienced on Earth's surface, either in the form of direct/refracted sunlight or in reflected light bouncing off the surfaces and/or atmospheres of our Moon and the visible planets. Ground illuminance, defined as the amount of visible light intercepting a unit area of surface (from all incident angles), varies over 7 orders of magnitude from day to night. It is highly dependent on well-modeled factors such as the relative positions of the Sun, Earth, and Moon. It is also dependent on less predictable factors such as local atmospheric conditions and weather. Several models have been proposed to predict ground illuminance, including Brown (1952) and Shapiro (1982, 1987). The Brown model is a set of empirical data collected from observation points around the world that has been reduced to a smooth fit of illuminance against a single variable, solar altitude. It provides limited applicability to the Moon and for cloudy conditions via multiplicative reduction factors. The Shapiro model is a theoretical model that treats the atmosphere as a three layer system of light reflectance and transmittance. It has different sets of reflectance and transmittance coefficients for various cloud types. Ground illuminance data from an observing run at the White Sands missile range were obtained from the United Kingdom Meteorology Office. Based on available weather reports, five days of clear sky observations were selected. These data are compared to the predictions of the two models. We find that neither of the models provide an accurate treatment during twilight conditions when the Sun is at or a few degrees below the horizon. When the Sun is above the horizon, the Shapiro model straddles the observed data, ranging between 90% and 120% of the recorded illuminance. During the same times, the Brown model is between 70% and 90% of the

  19. 94. Detail view of ground level at platform, pit "C", ...

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

    94. Detail view of ground level at platform, pit "C", elevator doors in closed position, exhaust vent on left, and elevator platform controls on right, looking northwest - Nike Missile Battery MS-40, County Road No. 260, Farmington, Dakota County, MN

  20. Novel technique for measuring grounding capacitance and grounding fault resistance in ineffectively grounded power system

    NASA Astrophysics Data System (ADS)

    Zeng, Xiangjun; Yin, Xianggen; Zhang, Zhe; Chen, Deshu; Yu, Yongyuan

    2000-05-01

    A new principle for resonance measurement based on injecting resonant frequency signal is presented in this paper. By this principle, the grounding capacitance and grounding resistance can be measured on-line in ineffectively grounding power system. Based on it, Petersen-coil automatically tuning is implemented, and 100% stator grounding fault protection for generator stator windings is also proposed. The prototype for Petersen-coil tuning has been tested on the network for many years. As well as the new method for generator stator grounding fault is verified by simulation.

  1. 2011 Ground Testing Highlights Article

    NASA Technical Reports Server (NTRS)

    Ross, James C.; Buchholz, Steven J.

    2011-01-01

    Two tests supporting development of the launch abort system for the Orion MultiPurpose Crew Vehicle were run in the NASA Ames Unitary Plan wind tunnel last year. The first test used a fully metric model to examine the stability and controllability of the Launch Abort Vehicle during potential abort scenarios for Mach numbers ranging from 0.3 to 2.5. The aerodynamic effects of the Abort Motor and Attitude Control Motor plumes were simulated using high-pressure air flowing through independent paths. The aerodynamic effects of the proximity to the launch vehicle during the early moments of an abort were simulated with a remotely actuated Service Module that allowed the position relative to the Crew Module to be varied appropriately. The second test simulated the acoustic environment around the Launch Abort Vehicle caused by the plumes from the 400,000-pound thrust, solid-fueled Abort Motor. To obtain the proper acoustic characteristics of the hot rocket plumes for the flight vehicle, heated Helium was used. A custom Helium supply system was developed for the test consisting of 2 jumbo high-pressure Helium trailers, a twelve-tube accumulator, and a 13MW gas-fired heater borrowed from the Propulsion Simulation Laboratory at NASA Glenn Research Center. The test provided fluctuating surface pressure measurements at over 200 points on the vehicle surface that have now been used to define the ground-testing requirements for the Orion Launch Abort Vehicle.

  2. Characterization of Finite Ground Coplanar Waveguide with Narrow Ground Planes

    NASA Technical Reports Server (NTRS)

    Ponchak, George E.; Tentzeris, Emmanouil M.; Katehi, Linda P. B.

    1997-01-01

    Coplanar waveguide with finite width ground planes is characterized through measurements, conformal mapping, and the Finite Difference Time Domain (FDTD) technique for the purpose of determining the optimum ground plane width. The attenuation and effective permittivity of the lines are related to its geometry. It is found that the characteristics of the Finite Ground Coplanar line (FGC) are not dependent on the ground plane width if it is greater than twice the center conductor width, but less than lambda(sub d)/8. In addition, electromagnetic field plots are presented which show for the first time that electric fields in the plane of the substrate terminate on the outer edge of the ground plane, and that the magnitude of these fields is related to the ground plane width.

  3. Ground potential rise monitor

    DOEpatents

    Allen, Zachery W.; Zevenbergen, Gary A.

    2012-04-03

    A device and method for detecting ground potential rise (GPR) comprising positioning a first electrode and a second electrode at a distance from each other into the earth. The voltage of the first electrode and second electrode is attenuated by an attenuation factor creating an attenuated voltage. The true RMS voltage of the attenuated voltage is determined creating an attenuated true RMS voltage. The attenuated true RMS voltage is then multiplied by the attenuation factor creating a calculated true RMS voltage. If the calculated true RMS voltage is greater than a first predetermined voltage threshold, a first alarm is enabled at a local location. If user input is received at a remote location acknowledging the first alarm, a first alarm acknowledgment signal is transmitted. The first alarm acknowledgment signal is then received at which time the first alarm is disabled.

  4. Economical ground data delivery

    NASA Technical Reports Server (NTRS)

    Markley, Richard W.; Byrne, Russell H.; Bromberg, Daniel E.

    1994-01-01

    Data delivery in the Deep Space Network (DSN) involves transmission of a small amount of constant, high-priority traffic and a large amount of bursty, low priority data. The bursty traffic may be initially buffered and then metered back slowly as bandwidth becomes available. Today both types of data are transmitted over dedicated leased circuits. The authors investigated the potential of saving money by designing a hybrid communications architecture that uses leased circuits for high-priority network communications and dial-up circuits for low-priority traffic. Such an architecture may significantly reduce costs and provide an emergency backup. The architecture presented here may also be applied to any ground station-to-customer network within the range of a common carrier. The authors compare estimated costs for various scenarios and suggest security safeguards that should be considered.

  5. Ground-penetrating rada

    NASA Astrophysics Data System (ADS)

    Thuma, W. R.

    The theory and applications of digital Ground-Penetrating Radar were discussed at a 5-day seminar held at the China University of Geosciences in Wuhan, People's Republic of China, in April. Cohosted by the Department of Applied Geophysics and Canada-China Geoscience, more than 60 senior geophysicists, engineers, technical specialists, university professors and researchers attended.Focus of the meeting was the expanded uses of the new deep-penetrating fully digital PulseEKKO, which is gaining wide acceptance around the world. Attendees showed intense interest in this new and unique technology. Applications covered were groundwater and mineral exploration; engineering, construction and toxic waste site surveying; tunnel and underground mine probing for potential geological hazards, blind ore zones, karst cavities and solution pathways; and locating buried objects such as petroleum storage tanks, unexploded bombs and archeological remains.

  6. Integrated Ground Operations Demonstration Units Testing Plans and Status

    NASA Technical Reports Server (NTRS)

    Johnson, Robert G.; Notardonato, William U.; Currin, Kelly M.; Orozco-Smith, Evelyn M.

    2012-01-01

    Cryogenic propellant loading operations with their associated flight and ground systems are some of the most complex, critical activities in launch operations. Consequently, these systems and operations account for a sizeable portion of the life cycle costs of any launch program. NASA operations for handling cryogens in ground support equipment have not changed substantially in 50 years, despite advances in cryogenics, system health management and command and control technologies. This project was developed to mature, integrate and demonstrate advancement in the current state of the art in these areas using two distinct integrated ground operations demonstration units (GODU): GODU Integrated Refrigeration and Storage (IRAS) and GODU Autonomous Control

  7. Burial Ground Expansion Hydrogeologic Characterization

    SciTech Connect

    Gaughan , T.F.

    1999-02-26

    Sirrine Environmental Consultants provided technical oversight of the installation of eighteen groundwater monitoring wells and six exploratory borings around the location of the Burial Ground Expansion.

  8. Method of locating ground faults

    NASA Astrophysics Data System (ADS)

    Patterson, Richard L.; Rose, Allen H.; Cull, Ronald C.

    1994-11-01

    The present invention discloses a method of detecting and locating current imbalances such as ground faults in multiwire systems using the Faraday effect. As an example, for 2-wire or 3-wire (1 ground wire) electrical systems, light is transmitted along an optical path which is exposed to magnetic fields produced by currents flowing in the hot and neutral wires. The rotations produced by these two magnetic fields cancel each other, therefore light on the optical path does not read the effect of either. However, when a ground fault occurs, the optical path is exposed to a net Faraday effect rotation due to the current imbalance thereby exposing the ground fault.

  9. Method of locating ground faults

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L. (Inventor); Rose, Allen H. (Inventor); Cull, Ronald C. (Inventor)

    1994-01-01

    The present invention discloses a method of detecting and locating current imbalances such as ground faults in multiwire systems using the Faraday effect. As an example, for 2-wire or 3-wire (1 ground wire) electrical systems, light is transmitted along an optical path which is exposed to magnetic fields produced by currents flowing in the hot and neutral wires. The rotations produced by these two magnetic fields cancel each other, therefore light on the optical path does not read the effect of either. However, when a ground fault occurs, the optical path is exposed to a net Faraday effect rotation due to the current imbalance thereby exposing the ground fault.

  10. 46 CFR 183.376 - Grounded distribution systems (neutral grounded).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... VESSELS (UNDER 100 GROSS TONS) ELECTRICAL INSTALLATION Power Sources and Distribution Systems § 183.376... must be only one connection to ground, regardless of the number of power sources. This ground... propulsion, power, lighting, or distribution system having a neutral bus or conductor must have the...

  11. SUPERFUND GROUND WATER ISSUE: GROUND WATER SAMPLING FOR METALS ANALYSES

    EPA Science Inventory

    Filtration of ground-water samples for metals analysis is an issue identified by the Forum as a concern of Superfund decision-makers. Inconsistency in EPA Syperfund cleanup pracices occurs where one EPA Region implements a remedial action based on unfiltered ground-water samples,...

  12. HANDBOOK: GROUND WATER VOLUME I: GROUND WATER AND CONTAMINATION

    EPA Science Inventory

    This handbook is an extensively revised version of the Ground Water Handbook, originally published in 1987 as EPA/625/6-87/016. It has been published in two volumes: Volume I: Ground Water and Contamination, EPA/625/6-90/016a, and Volume II: Methodology, EPA/625/6-90/016b. Volume...

  13. Study of the deformation mechanism of the Gaoliying ground fissure

    NASA Astrophysics Data System (ADS)

    Cheng, G.; Wang, H.; Luo, Y.; Guo, H.

    2015-11-01

    The Gaoliying ground fissure in Beijing has caused building cracking and road damage, and has seriously influenced city construction. Based on investigations and trenching, the influences of the fault and the variation of groundwater levels on the formation mechanism of the Gaoliying ground fissure were investigated by using FLAC3D. The results indicated that (1) the surface location of Gaoliying fissure is controlled by the underlying normal fault activity, and over pumping further exacerbates development of the ground fissure; (2) when the groundwater level declines, obvious differential settlement occurs at both sides of the ground fissure, in which greater settlement occurs in the vicinity of the hanging wall, the greater the distance from the hanging wall, the smaller the ground subsidence, however smaller ground subsidence occurs in the vicinity of the footwall, the greater the distance from the footwall, the greater the ground subsidence; (3) the vertical velocity of the ground fissure triggered by the fault activity and groundwater decline ranges from 15.5 to 18.3 mm a-1, which is basically in line with the monitoring data. The fault activity contributes about 28-39 %, and the groundwater contributes about 61-72 % to the deformation of the ground fissure, respectively.

  14. Acoustic ground impedance meter

    NASA Technical Reports Server (NTRS)

    Zuckerwar, A. J.

    1981-01-01

    A compact, portable instrument was developed to measure the acoustic impedance of the ground, or other surfaces, by direct pressure-volume velocity measurement. A Helmholz resonator, constructed of heavy-walled stainless steel but open at the bottom, is positioned over the surface having the unknown impedance. The sound source, a cam-driven piston of known stroke and thus known volume velocity, is located in the neck of the resonator. The cam speed is a variable up to a maximum 3600 rpm. The sound pressure at the test surface is measured by means of a microphone flush-mounted in the wall of the chamber. An optical monitor of the piston displacement permits measurement of the phase angle between the volume velocity and the sound pressure, from which the real and imaginary parts of the impedance can be evaluated. Measurements using a 5-lobed cam can be made up to 300 Hz. Detailed design criteria and results on a soil sample are presented.

  15. Using Tremor to Predict Strong Ground Motion

    NASA Astrophysics Data System (ADS)

    Baltay, A.; Asawachaisujja, S.; Beroza, G. C.

    2012-12-01

    Due to its widespread occurrence, frequency content, and location, tectonic tremor presents an exceptional opportunity to test and improve strong ground motion attenuation relations for subduction zones. We characterize the amplitude of thousands of individual tremor events to constrain the distance attenuation relationship of peak ground acceleration (PGA) and peak ground velocity (PGV) of tremor for application to strong ground motion prediction. Ground motion prediction equations (GMPE) relate ground motion amplitude to earthquake magnitude and distance, and are critically important for creating seismic hazard maps. In practice, GMPEs are determined empirically with earthquake data, recorded at many stations. In some areas of high earthquake hazard, such as Cascadia, the data set of recorded earthquakes for ground motion prediction is extremely sparse. Tectonic tremor, however, occurs frequently and abundantly in many subduction zones, including Cascadia. Moreover, the tremor band of 1-10 Hz, corresponds precisely to the frequency band of greatest interest for engineering seismology. Finally, tremor is thought to occur at or near the down-dip limit of rupture in large megathrust earthquakes, which is the area that is likely to control high frequency shaking in large earthquakes. Tremor in Cascadia is strong enough to be recorded at borehole stations of the Plate Boundary Observatory to distances of nearly 200 km, which is sufficient to place important constraints on ground motion decay with distance. We characterize the amplitude of thousands of individual tremor events occurring nearly continuously throughout an ETS event, using tremor locations and timings from independently determined catalogs [Wech and Creager, 2008]. Because tremor bursts do not have a defined absolute magnitude, we normalize all events to a reference magnitude. PGA and PGV for tremor shows a distance decay that is similar to subduction-zone-specific GMPEs developed from both data and

  16. Operational Considerations when Designing New Ground Systems

    NASA Technical Reports Server (NTRS)

    Walyus, Keith; Barbahenn, George; Crabb, William; Miebach, Manfred; Pataro, Peter

    2000-01-01

    The Hubble Space Telescope (HST) launched in April of 1991 with a nominal 15-year old mission. Since then, the HST mission life has been extended to 2010. As is true for all NASA missions, HST is being asked to decrease its operational costs for the remainder of its mission life. Various techniques are being incorporated for cost reductions, with one of the core means being the design of a new and more efficient ground system for HST operations. This new ground system, "Vision 2000", will reduce operational and maintenance costs and also provide the HST Project with added flexibility to react to future changes. Vision 2000 began supporting HST Operations in January of 1999 and will support the mission for the remainder of the mission life. Upgrading a satellite's ground system is a popular approach for reducing costs, but it is also inherently risky. Validating a new ground system can be a severe distraction to a flight team while operating a satellite. Mission data collection and health and safety requirements are rarely, if ever, relaxed during this validation period, forcing flight teams to undertake an additional task while operating the satellite. Additionally, flight teams must usually undergo extensive training to effectively utilize the new system. Once again, this training usually occurs as an additional task, in addition to the nominal satellite operations. While operating the spacecraft, the Flight Team typically assists in the design, validation, and verification of a new ground system. This is a distraction and strain on the Flight Team, but the benefit of using the Flight Team in all phases of ground system development far outweigh the negative aspects. Finally, above the cost of the new system, the integration into the facility with the current control center system are resources and costs not normally taken into account in the design phase of the new system. In addition to the standard issues faced by a Project when upgrading its ground system, the

  17. Hypersonic Inflatable Aerodynamic Decelerator Ground Test Development

    NASA Technical Reports Server (NTRS)

    Del Corso, Jospeh A.; Hughes, Stephen; Cheatwood, Neil; Johnson, Keith; Calomino, Anthony

    2015-01-01

    Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology readiness levels have been incrementally matured by NASA over the last thirteen years, with most recent support from NASA's Space Technology Mission Directorate (STMD) Game Changing Development Program (GCDP). Recently STMD GCDP has authorized funding and support through fiscal year 2015 (FY15) for continued HIAD ground developments which support a Mars Entry, Descent, and Landing (EDL) study. The Mars study will assess the viability of various EDL architectures to enable a Mars human architecture pathfinder mission planned for mid-2020. At its conclusion in November 2014, NASA's first HIAD ground development effort had demonstrated success with fabricating a 50 W/cm2 modular thermal protection system, a 400 C capable inflatable structure, a 10-meter scale aeroshell manufacturing capability, together with calibrated thermal and structural models. Despite the unquestionable success of the first HIAD ground development effort, it was recognized that additional investment was needed in order to realize the full potential of the HIAD technology capability to enable future flight opportunities. The second HIAD ground development effort will focus on extending performance capability in key technology areas that include thermal protection system, lifting-body structures, inflation systems, flight control, stage transitions, and 15-meter aeroshell scalability. This paper presents an overview of the accomplishments under the baseline HIAD development effort and current plans for a follow-on development effort focused on extending those critical technologies needed to enable a Mars Pathfinder mission.

  18. Program Analyzes Spacecraft/Ground Radio Links

    NASA Technical Reports Server (NTRS)

    Lansing, Faiza; Kantak, Anil

    2007-01-01

    A versatile computer program analyzes the link-design control table necessary for designing the telecommunication subsystem of a spacecraft in orbit around the Earth or on a deep-space mission. The program helps to calculate all the important parameter values for spacecraft-to-ground telemetry links and ground-to-spacecraft command links. The program also enables the design of turn-around ranging and one-way ranging links, which are very useful for determining the positions of spacecraft and for satisfying various other operational needs. The user can specify several aspects of spacecraft telecommunication-subsystem design, including the nature of the antenna (paraboloidal reflector, patch, dipole, etc.), the power-amplifier rating, and the link data rate. The program enables the use of comparative design procedures and includes an extensive database on the capabilities, attributes, and costs of commercially available telecommunications equipment. Hence, the program can also perform cost analyses. The software includes an extensive ground-station database, so that link design can be carried out using different ground stations in a comparative process in an effort to select the best design. The output of the program is in the form of graphs as well as numbers.

  19. Display integration for ground combat vehicles

    NASA Astrophysics Data System (ADS)

    Busse, David J.

    1998-09-01

    The United States Army's requirement to employ high resolution target acquisition sensors and information warfare to increase its dominance over enemy forces has led to the need to integrate advanced display devices into ground combat vehicle crew stations. The Army's force structure require the integration of advanced displays on both existing and emerging ground combat vehicle systems. The fielding of second generation target acquisition sensors, color digital terrain maps and high volume digital command and control information networks on these platforms define display performance requirements. The greatest challenge facing the system integrator is the development and integration of advanced displays that meet operational, vehicle and human computer interface performance requirements for the ground combat vehicle fleet. The subject of this paper is to address those challenges: operational and vehicle performance, non-soldier centric crew station configurations, display performance limitations related to human computer interfaces and vehicle physical environments, display technology limitations and the Department of Defense (DOD) acquisition reform initiatives. How the ground combat vehicle Program Manager and system integrator are addressing these challenges are discussed through the integration of displays on fielded, current and future close combat vehicle applications.

  20. Ground Taxi Navigation Problems and Training Solutions

    NASA Technical Reports Server (NTRS)

    Quinn, Cheryl; Walter, Kim E.; Rosekind, Mark (Technical Monitor)

    1997-01-01

    Adverse weather conditions can put considerable strain on the National Airspace System. Even small decreases in visibility on the airport surface can create delays, hinder safe movement and lead to errors. Studies of Aviation Safety Reporting System (ASRS) surface movement incidents support the need for technologies and procedures to improve ground operations in low-visibility conditions. This study examined 139 ASRS reports of low-visibility surface movement incidents at 10 major U.S. airports. Errors were characterized in terms of incident type, contributing factors and consequences. The incidents in the present sample were comprised of runway transgressions, taxiway excursions and ground conflicts. The primary contributing factors were Airport Layout and Markings, Communication and Distraction. In half the incidents the controller issued a new clearance or the flight crew took an evasive action and in the remaining half, no recovery attempt was made because the error was detected after the fact. By gaining a better understanding the factors that affect crew navigation in low visibility and the types of errors that are likely to occur, it will be possible to develop more robust technologies to aid pilots in the ground taxi task. Implications for crew training and procedure development for low-visibility ground taxi are also discussed.

  1. Operational Guidelines for Grounds Management.

    ERIC Educational Resources Information Center

    APPA: Association of Higher Education Facilities Officers, Alexandria, VA.

    This book offers guidelines intended to help both new and experienced grounds managers create operational and staffing-level plans that can be the basis of discussion with all grounds management stakeholders. In its various chapters, the book: (1) explains the differences between zone and broadcast maintenance practices that are essential to plan…

  2. English for Airport Ground Staff

    ERIC Educational Resources Information Center

    Cutting, Joan

    2012-01-01

    This article describes part of a European Commission Leonardo project that aimed to design a multimedia course for English language learners seeking work as ground staff in European airports. The structural-functional analysis of the dialogues written from the course showed that, across the four trades explored (security guards, ground handlers,…

  3. Ground-penetrating radar methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ground-penetrating radar geophysical methods are finding greater and greater use in agriculture. With the ground-penetrating radar (GPR) method, an electromagnetic radio energy (radar) pulse is directed into the subsurface, followed by measurement of the elapsed time taken by the radar signal as it ...

  4. Designing the Successful Grounds Organization

    ERIC Educational Resources Information Center

    Gratto, Fred

    2011-01-01

    The most important component of any service organization is people. This is especially true of grounds management, because effective maintenance is dependent on good supervision and knowledgeable people. The grounds management function, therefore, must have personnel who are competent and committed. They must fully understand the scope of their …

  5. Ground water and climate change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As the world’s largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food secu¬rity will probably intensify under climate chan...

  6. LASRE ground hotfire #2

    NASA Technical Reports Server (NTRS)

    1997-01-01

    operation characteristics. The first of these flights occurred March 4, 1998. The SR-71 took off at 10:16 a.m. PST. The aircraft flew for one hour and fifty-seven minutes, reaching a maximum speed of Mach 1.58 before landing at Edwards, California, at 12:13 p.m. PST. During further flights in the spring and summer of 1998, liquid oxygen was cycled through the engine. In addition, two engine hot firings were conducted on the ground. It was decided not to do a final hot-fire flight test as a result of the liquid oxygen leaks in the test apparatus. The ground firings and the airborne cryogenic gas flow tests provided enough information to predict the hot gas effects of an aerospike engine firing during flight. The experiment itself was a small, half-span model that contained eight thrust cells of an aerospike engine and was mounted on a housing known as the 'canoe,' which contained the gaseous hydrogen, helium and instrumentation. The model, engine and canoe together were called the 'pod.' The entire pod was 41 feet in length and weighed 14,300 pounds. The experimental pod was mounted on NASA's SR-71, on loan to NASA from the U.S. Air Force. Lockheed Martin may use information gained from LASRE and the X-33 Advanced Technology Demonstrator to develop a potential future reusable launch vehicle. NASA and Lockheed Martin are partners in the X-33 program through a cooperative agreement.The goal of the X-33 program, and a major goal for NASA's Office of Aero-Space Technology, has been to enable significant reductions in the cost of access to space, and to promote the creation and delivery of new space services and other activities that will improve U.S. economic competitiveness. The program implements the National Space Transportation Policy, which was designed to accelerate the development of new launch technologies and concepts that contribute to the continuing commercialization of the national space launch industry. Both the flagship X-33 and the smaller X-34 technology testbed

  7. Snowpack ground-truth manual

    NASA Technical Reports Server (NTRS)

    Jones, E. B.

    1983-01-01

    As remote sensing increasingly becomes more of an operational tool in the field of snow management and snow hydrology, there is need for some degree of standardization of ""snowpack ground truth'' techniques. This manual provides a first step in standardizing these procedures and was prepared to meet the needs of remote sensing researchers in planning missions requiring ground truth as well as those providing the ground truth. Focus is on ground truth for remote sensors primarily operating in the microwave portion of the electromagnetic spectrum; nevertheless, the manual should be of value to other types of sensor programs. This first edition of ground truth procedures must be updated as new or modified techniques are developed.

  8. Movable Ground Based Recovery System for Reuseable Space Flight Hardware

    NASA Technical Reports Server (NTRS)

    Sarver, George L. (Inventor)

    2013-01-01

    A reusable space flight launch system is configured to eliminate complex descent and landing systems from the space flight hardware and move them to maneuverable ground based systems. Precision landing of the reusable space flight hardware is enabled using a simple, light weight aerodynamic device on board the flight hardware such as a parachute, and one or more translating ground based vehicles such as a hovercraft that include active speed, orientation and directional control. The ground based vehicle maneuvers itself into position beneath the descending flight hardware, matching its speed and direction and captures the flight hardware. The ground based vehicle will contain propulsion, command and GN&C functionality as well as space flight hardware landing cushioning and retaining hardware. The ground based vehicle propulsion system enables longitudinal and transverse maneuverability independent of its physical heading.

  9. Sail GTS ground system analysis: Avionics system engineering

    NASA Technical Reports Server (NTRS)

    Lawton, R. M.

    1977-01-01

    A comparison of two different concepts for the guidance, navigation and control test set signal ground system is presented. The first is a concept utilizing a ground plate to which crew station, avionics racks, electrical power distribution system, master electrical common connection assembly and marshall mated elements system grounds are connected by 4/0 welding cable. An alternate approach has an aluminum sheet interconnecting the signal ground reference points between the crew station and avionics racks. The comparison analysis quantifies the differences between the two concepts in terms of dc resistance, ac resistance and inductive reactance. These parameters are figures of merit for ground system conductors in that the system with the lowest impedance is the most effective in minimizing noise voltage. Although the welding cable system is probably adequate, the aluminum sheet system provides a higher probability of a successful system design.

  10. 14 CFR 121.421 - Flight attendants: Initial and transition ground training.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION... equipment and the controls for cabin heat and ventilation. (b) Initial and transition ground training...

  11. Longevity of Emplacement Drift Ground Support Materials

    SciTech Connect

    Tang, David H.

    2001-05-30

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for the selection of materials for ground support that will function throughout the preclosure period of a potential repository at Yucca Mountain. REV 01 ICN 01 of this analysis is developed in accordance with AP-3.10Q, Analyses and Models, Revision 2, ICN 4, and prepared in accordance with the Technical Work Plan for Subsurface Design Section FY 01 Work Activities (CRWMS M&O 2001a). The objective of this analysis is to update the previous analysis (CRWMS M&O 2000a) to account for related changes in the Ground Control System Description Document (CRWMS M&O 2000b), the Monitored Geologic Repository Project Description Document, which is included in the Requirements and Criteria for Implementing a Repository Design that can be Operated Over a Range of Thermal Modes (BSC 2001), input information, and in environmental conditions, and to provide updated information on candidate ground support materials. Candidate materials for ground support are carbon steel and cement grout. Steel is mainly used for steel sets, lagging, channel, rock bolts, and wire mesh. Cement grout is only considered in the case of grouted rock bolts. Candidate materials for the emplacement drift invert are carbon steel and granular natural material. Materials are evaluated for the repository emplacement drift environment based on the updated thermal loading condition and waste package design. The analysis consists of the following tasks: (1) Identify factors affecting the longevity of ground support materials for use in emplacement drifts. (2) Review existing documents concerning the behavior of candidate ground support materials during the preclosure period. (3) Evaluate impacts of temperature and radiation effects on mechanical and thermal properties of steel. Assess corrosion potential of steel at emplacement drift environment. (4) Evaluate factors

  12. Individual Atoms in their Quantum Ground State

    NASA Astrophysics Data System (ADS)

    Schwartz, Eyal; Sompet, Pimonpan; Fung, Yin Hsien; Andersen, Mikkel F.

    2016-05-01

    An ultimate control of pure quantum states is an excellent platform for various quantum science and engineering. In this work, we perform quantum manipulation of individual Rubidium atoms in a tightly focus optical tweezer in order to cool them into their vibrational ground state via Raman sideband cooling. Our experimental scheme involves a combination of Raman sideband transitions and optical pumping of the atoms that couples two magnetic field sublevels indifferent to magnetic noise thus providing a much longer atomic coherence time compared to previous cooling schemes. By installing most of the atoms in their ground state, we managed to achieve two-dimensional cooling on the way to create a full nil entropy quantum state of single atoms and single molecules. We acknowledge the Marsden Fund, CORE and DWC for their support.

  13. Procedures for ground-water investigations

    SciTech Connect

    Not Available

    1989-09-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water investigations are carried out to fulfill the requirements for the US Department of Energy (DOE) to meet the requirements of DOE Orders. Investigations are also performed for various clients to meet the requirements of the Resource Conservation and Recovery Act of 1976 (RCRA) and the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA). National standards including procedures published by the American Society for Testing and Materials (ASTM) and the US Geological Survey were utilized in developing the procedures contained in this manual.

  14. Mitigating ground clutter effects with lightweight artificial dielectrics

    NASA Astrophysics Data System (ADS)

    Rappaport, Carey M.; Beihold, Fred; Linnehan, Robert

    2001-10-01

    The problem of scattered and transmitted electromagnetic wave distortion by random rough ground surfaces can be reduced by using a lightweight dielectric matching layer. For mine detection applications, it is essential for this layer to be lightweight, low loss, readily conformable, and adaptable to different soil types. Arrays of metal-coated plastic spheres act as lossless artificial dielectrics with impedance determined by the volume packing fraction. By controlling the thickness of insulator surrounding each sphere, a close-packed array with the dielectric properties of soil can be created inside a compliant rolling bag that will conform to the rough surface of the ground. Since this artificial dielectric is matched to the soil, the ground surface interface is 'softened', without an abrupt transition from soil to air. Signals transmitted and received by GPR antennas immersed in the artificial dielectric within the bag will not be corrupted by ground surface clutter. Alternatively, an artificial dielectric layer on the ground with a planar air interface could be used to ensure that the surface reflection is a constant, well-calibrated signal. Computational models indicate complete removal of the ground clutter, even with occasional gaps between the artificial dielectric and the ground. Experimental studies with swept-frequency measurements and impulse GPR indicate that using this dielectric layer matching to a rough loamy soil ground surface is results in signals that are practically indistinguishable from those of an equivalent layer of the same type of soil.

  15. Ground Effect - Theory and Practice

    NASA Technical Reports Server (NTRS)

    Pistolesi, E

    1937-01-01

    The conclusion of a previous article by Pistolesi is that the increment of lift due to ground effect is largely attributable to the effect of induction of the free vortices, and is practically equivalent to a virtual increase in aspect ratio. The ground clearance was of the order of magnitude comparable to the wing chord. New reports by Le Seur and Datwyler treat the case of minimum distance from the ground and is confined to the plane problem only. The author briefly reviews these reports and also one by Timotika. References to all the reviewed reports are in the attached bibliography.

  16. LANDSAT-D ground segment operations plan, revision A

    NASA Technical Reports Server (NTRS)

    Evans, B.

    1982-01-01

    The basic concept for the utilization of LANDSAT ground processing resources is described. Only the steady state activities that support normal ground processing are addressed. This ground segment operations plan covers all processing of the multispectral scanner and the processing of thematic mapper through data acquisition and payload correction data generation for the LANDSAT 4 mission. The capabilities embedded in the hardware and software elements are presented from an operations viewpoint. The personnel assignments associated with each functional process and the mechanisms available for controlling the overall data flow are identified.

  17. Investigation of direct expansion in ground source heat pumps

    NASA Astrophysics Data System (ADS)

    Kalman, M. D.

    A fully instrumented subscale ground coupled heat pump system was developed, and built, and used to test and obtain data on three different earth heat exchanger configurations under heating conditions (ground cooling). Various refrigerant flow control and compressor protection devices were tested for their applicability to the direct expansion system. Undistributed Earth temperature data were acquired at various depths. The problem of oil return at low evaporator temperatures and low refrigerant velocities was addressed. An analysis was performed to theoretically determine what evaporator temperature can be expected with an isolated ground pipe configuration with given length, pipe size, soil conditions and constant heat load. Technical accomplishments to data are summarized.

  18. Lean and Agile Development of the AITS Ground Software System

    NASA Astrophysics Data System (ADS)

    Richters, Mark; Dutruel, Etienne; Mecredy, Nicolas

    2013-08-01

    We present the ongoing development of a new ground software system used for integrating, testing and operating spacecraft. The Advanced Integration and Test Services (AITS) project aims at providing a solution for electrical ground support equipment and mission control systems in future Astrium Space Transportation missions. Traditionally ESA ground or flight software development projects are conducted according to a waterfall-like process as specified in the ECSS-E-40 standard promoted by ESA in the European industry. In AITS a decision was taken to adopt an agile development process. This work could serve as a reference for future ESA software projects willing to apply agile concepts.

  19. 46 CFR 129.375 - System grounding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false System grounding. 129.375 Section 129.375 Shipping COAST... Power Sources and Distribution Systems § 129.375 System grounding. (a) If a grounded distribution system... connected to a common ground plate, except that no aluminum grounding conductors may be used. (c) On...

  20. 46 CFR 129.375 - System grounding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false System grounding. 129.375 Section 129.375 Shipping COAST... Power Sources and Distribution Systems § 129.375 System grounding. (a) If a grounded distribution system... connected to a common ground plate, except that no aluminum grounding conductors may be used. (c) On...