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Sample records for experiment fordetermining hysteretic

  1. Inverse modeling of a multistep outflow experiment fordetermining hysteretic hydraulic properties

    SciTech Connect

    Faybishenko, B.; Finsterle, S.; Sonnenborg, T.O.

    1998-05-01

    A new, closed-form hysteretic model of the capillary pressure-saturation and relative permeability-saturation relationship has been implemented into ITOUGH2. The hysteretic capillary pressure function is based on the van Genuchten model, with a modified version of the dependent domain model of Mualem to describe the scanning curves. Hysteresis in the relative permeability relations is considered to be mainly a result of nonwetting fluid entrap- ment. The hysteresis model was used in combination with inverse modeling techniques to examine the potential of a simple drainage- imbibition experiment to determine hysteretic hydraulic properties.

  2. Hysteretic behavior in torsional oscillator experiments & de Gennes, Bean and Livingston effect in hcp 4He

    NASA Astrophysics Data System (ADS)

    Kubota, Minoru; Ueda, Hiroaki; Yagi, Masahiko; Shimizu, Nobutaka; Rogacki, Kris.; Inoue, Kazuo

    2014-03-01

    Recent reports on the absence of supersolid signal in 4He in Vycor as well as reports on effects of the sample elasticity to torsional oscillator (TO) experiments caused people to ask if supersolid may not exist. There are recent activities to check such questions more quantitatively. We revisit our TO study, which was performed on relatively small number of bulk hcp 4He samples, but under quite different conditions as under DC rotation as well as under wide range of AC excitation Vac with extremely high stability. We proposed a transition at Tc = 75(~ 60) mK well below the onset temperature of the anomaly around 500 mK in the same sample. The transition at Tc was detected by three independent methods. Namely, the hysteresis appears below this Tc when AC excitation was changed under a certain sequence. We analyzed the maximum period shift across the hysteretic loop as a function of Vac. This quantity appears abruptly below Tc and surprisingly its T dependence coincides with that of the extra energy dissipation rotational velocity Omega linear slope under DC rotation, also below Tc. We discuss that the maximum is caused by de Gennes, Bean and Livingston effect, which is a quantized vortices effect known for superconductors. The third Tc detection is given by a jump in the log Vac linear dependence of the period shift. Authors acknowledge support from ISSP, Univ. Tokyo.

  3. An analytical model of dissipated viscous and hysteretic energy due to interaction forces in a pneumatic tire: Theory and experiments

    NASA Astrophysics Data System (ADS)

    Brancati, Renato; Strano, Salvatore; Timpone, Francesco

    2011-10-01

    When in use, a tire dissipates energy according to various mechanisms: rolling resistance, viscosity, hysteresis, friction energy, etc. This dissipation of energy contributes to influencing tire temperature, contact conditions and the resulting friction coefficient. This research project deals with viscoelastic and hysteretic mechanisms, and presents an explicit expression of the energy dissipated by tire-road interactions caused by these mechanisms. It is based on the Dahl model with regard to the hysteretic force together with a spring and a frequency variable damping coefficient with regard to the viscoelastic one. The energy expression found in this way can be used in tire thermal models to determine one of the heat flows needed to estimate the contact temperature and to find out the actual friction coefficient to be used in real time tire-road interaction models. Experimental tests were carried out, for longitudinal interaction only, in order to evaluate the effectiveness of the proposed expression by identifying the parameters and validating the results.

  4. Nonlinear Hysteretic Torsional Waves

    NASA Astrophysics Data System (ADS)

    Cabaret, J.; Béquin, P.; Theocharis, G.; Andreev, V.; Gusev, V. E.; Tournat, V.

    2015-07-01

    We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found to be nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other types of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short-term memory, as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control devices such as strong amplitude-dependent filters.

  5. Nonlinear Hysteretic Torsional Waves.

    PubMed

    Cabaret, J; Béquin, P; Theocharis, G; Andreev, V; Gusev, V E; Tournat, V

    2015-07-31

    We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found to be nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other types of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short-term memory, as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control devices such as strong amplitude-dependent filters.

  6. Probing hysteretic elasticity in weakly nonlinear materials

    SciTech Connect

    Johnson, Paul A; Haupert, Sylvain; Renaud, Guillaume; Riviere, Jacques; Talmant, Maryline; Laugier, Pascal

    2010-12-07

    Our work is aimed at assessing the elastic and dissipative hysteretic nonlinear parameters' repeatability (precision) using several classes of materials with weak, intermediate and high nonlinear properties. In this contribution, we describe an optimized Nonlinear Resonant Ultrasound Spectroscopy (NRUS) measuring and data processing protocol applied to small samples. The protocol is used to eliminate the effects of environmental condition changes that take place during an experiment, and that may mask the intrinsic elastic nonlinearity. As an example, in our experiments, we identified external temperature fluctuation as a primary source of material resonance frequency and elastic modulus variation. A variation of 0.1 C produced a frequency variation of 0.01 %, which is similar to the expected nonlinear frequency shift for weakly nonlinear materials. In order to eliminate environmental effects, the variation in f{sub 0} (the elastically linear resonance frequency proportional to modulus) is fit with the appropriate function, and that function is used to correct the NRUS calculation of nonlinear parameters. With our correction procedure, we measured relative resonant frequency shifts of 10{sup -5} , which are below 10{sup -4}, often considered the limit to NRUS sensitivity under common experimental conditions. Our results show that the procedure is an alternative to the stringent control of temperature often applied. Applying the approach, we report nonlinear parameters for several materials, some with very small nonclassical nonlinearity. The approach has broad application to NRUS and other Nonlinear Elastic Wave Spectroscopy approaches.

  7. Modeling geologic storage of carbon dioxide: Comparison ofnon-hysteretic and hysteretic characteristic curves

    SciTech Connect

    Doughty, Christine

    2006-07-17

    Numerical models of geologic storage of carbon dioxide (CO2)in brine-bearing formations use characteristic curves to represent theinteractions of non-wetting-phase CO2 and wetting-phase brine. When aproblem includes both injection of CO2 (a drainage process) and itssubsequent post-injection evolution (a combination of drainage andwetting), hysteretic characteristic curves are required to correctlycapture the behavior of the CO2 plume. In the hysteretic formulation,capillary pressure and relative permeability depend not only on thecurrent grid-block saturation, but also on the history of the saturationin the grid block. For a problem that involves only drainage or onlywetting, a non-hysteretic formulation, in which capillary pressure andrelative permeability depend only on the current value of the grid-blocksaturation, is adequate. For the hysteretic formulation to be robustcomputationally, care must be taken to ensure the differentiability ofthe characteristic curves both within and beyond the turning-pointsaturations where transitions between branches of the curves occur. Twoexample problems involving geologic CO2 storage are simulated withTOUGH2, a multiphase, multicomponent code for flow and transport codethrough geological media. Both non-hysteretic and hysteretic formulationsare used, to illustrate the applicability and limitations ofnon-hysteretic methods.The first application considers leakage of CO2from the storage formation to the ground surface, while the secondexamines the role of heterogeneity within the storageformation.

  8. Hysteretic magnetoresistance and unconventional anomalous Hall effect in the frustrated magnet TmB4

    NASA Astrophysics Data System (ADS)

    Sunku, Sai Swaroop; Kong, Tai; Ito, Toshimitsu; Canfield, Paul C.; Shastry, B. Sriram; Sengupta, Pinaki; Panagopoulos, Christos

    2016-05-01

    We study TmB4, a frustrated magnet on the Archimedean Shastry-Sutherland lattice, through magnetization and transport experiments. The lack of anisotropy in resistivity shows that TmB4 is an electronically three-dimensional system. The magnetoresistance (MR) is hysteretic at low temperature even though a corresponding hysteresis in magnetization is absent. The Hall resistivity shows unconventional anomalous Hall effect (AHE) and is linear above saturation despite a large MR. We propose that complex structures at magnetic domain walls may be responsible for the hysteretic MR and may also lead to the AHE.

  9. Hysteretic magnetoresistance and unconventional anomalous Hall effect in the frustrated magnet TmB4

    NASA Astrophysics Data System (ADS)

    Sunku, Sai Swaroop; Kong, Tai; Ito, Toshimitsu; Canfield, Paul C.; Shastry, B. Sriram; Sengupta, Pinaki; Panagopoulos, Christos

    We study TmB4, a frustrated magnet on the Archimedean Shastry-Sutherland lattice, through magnetization and transport experiments. The lack of anisotropy in resistivity shows that TmB4 is an electronically three-dimensional system. The magnetoresistance (MR) is hysteretic at low-temperature even though a corresponding hysteresis in magnetization is absent. The Hall resistivity shows unconventional anomalous Hall effect (AHE) and is linear above saturation despite a large MR. We suggest that both hysteretic MR and AHE arise from the formation of complex non-coplanar structures at magnetic domain walls. Current address: Department of Applied Physics and Applied Mathematics, Columbia University.

  10. Hysteretic magnetoresistance and unconventional anomalous Hall effect in the frustrated magnet TmB4

    DOE PAGES

    Sunku, Sai Swaroop; Kong, Tai; Ito, Toshimitsu; ...

    2016-05-11

    We study TmB4, a frustrated magnet on the Archimedean Shastry-Sutherland lattice, through magnetization and transport experiments. The lack of anisotropy in resistivity shows that TmB4 is an electronically three-dimensional system. The magnetoresistance (MR) is hysteretic at low temperature even though a corresponding hysteresis in magnetization is absent. The Hall resistivity shows unconventional anomalous Hall effect (AHE) and is linear above saturation despite a large MR. In conclusion, we propose that complex structures at magnetic domain walls may be responsible for the hysteretic MR and may also lead to the AHE.

  11. Hysteretic damping in rotordynamics: An equivalent formulation

    NASA Astrophysics Data System (ADS)

    Genta, Giancarlo; Amati, Nicola

    2010-10-01

    The hysteretic damping model cannot be applied to time domain dynamic simulations: this is a well-known feature that has been discussed in the literature since the time when analog computers were widespread. The constant equivalent damping often introduced to overcome this problem is also discussed, and its limitations are stated, in particular those linked with its application in rotordynamics to simulate rotating damping. An alternative model based on the nonviscous damping (NVD) model, but with a limited number of additional degrees of freedom, is proposed, and the relevant equations are derived. Some examples show applications to the rotordynamics field.

  12. Random Response of Linear Hysteretic Damping

    SciTech Connect

    Floris, Claudio

    2008-07-08

    The probabilistic characterization of the response of a single-degree-of-freedom (SDOF) oscillator with linear hysteretic damping excited by ground motion described by zero mean stationary Gaussian processes is achieved by profiting from a steady-state solution of the motion equation, valid when the excitation is given by the superposition of harmonics. The model of linear hysteretic damping has been introduced to fit damping mechanisms in which the dissipation rate is independent of frequency, and mathematically it is described by the Hilbert transform of the response. Though this model is debated since it violates the principle of causality, its intrinsic simplicity makes it preferable to other models. The steady-state solution of the motion equation proposed in this paper allows a closed form evaluation of the respone mean square value. However, the numerical examples show that this quantity is affected by the mechanism of energy dissipation only when this is large. On the contrary, for a low capacity of dissipation the response mean square value is rather insensitive to the dissipation mechanism.

  13. On hysteretic response and stationary phase fronts in rubber

    NASA Astrophysics Data System (ADS)

    Niemczura, J.; Ravi-Chandar, K.

    2010-09-01

    We consider the dynamic response of natural, latex and synthetic, nitrile rubbers under non-monotonic dynamic loading conditions; in particular, we recreate an experiment first considered by Kolsky (Nature 224:1301, 1969) in which two segments of a long rubber specimen are initially maintained at different strain levels by external force and then allowed to evolve dynamically towards equilibrium. We show that as a result of the hysteretic behavior, a phase boundary that is stationary with respect to the material points can be established in both these materials. We also show that this phase boundary persists indefinitely in strain-crystallizing natural, latex rubber, but disappears quickly in the non-crystallizing nitrile rubber.

  14. Hysteretic behavior of soft magnetic elastomer composites

    NASA Astrophysics Data System (ADS)

    Krautz, Maria; Werner, David; Schrödner, Mario; Funk, Alexander; Jantz, Alexander; Popp, Jana; Eckert, Jürgen; Waske, Anja

    2017-03-01

    Composites of polymer and micron-sized particles of carbonyl-iron were investigated in terms of their magnetization behavior. Thermoplastic elastomers with varying Young's modulus (EPolymer=0.14-14.6 MPa) were used as matrix material. Field dependent magnetization curves reveal that the hysteretic behavior of the composites strongly depends on both the particle fraction (7, 10, 14, 21, 31 vol%) and on the mechanical properties of the polymer. It is shown that hysteresis only appears above a certain fraction of magnetic particles which can be accounted to the magnetic exchange between the particles. However, hysteresis is suppressed in the composite with largest Young's modulus of the polymer matrix, even at largest particle fraction.

  15. Adaptive control design for hysteretic smart systems

    NASA Astrophysics Data System (ADS)

    Fan, Xiang; Smith, Ralph C.

    2009-03-01

    Ferroelectric and ferromagnetic actuators are being considered for a range of industrial, aerospace, aeronautic and biomedical applications due to their unique transduction capabilities. However, they also exhibit hysteretic and nonlinear behavior that must be accommodated in models and control designs. If uncompensated, these effects can yield reduced system performance and, in the worst case, can produce unpredictable behavior of the control system. One technique for control design is to approximately linearize the actuator dynamics using an adaptive inverse compensator that is also able to accommodate model uncertainties and error introduced by the inverse algorithm. This paper describes the design of an adaptive inverse control technique based on the homogenized energy model for hysteresis. The resulting inverse filter is incorporated in an L1 control theory to provide a robust control algorithm capable of providing high speed, high accuracy tracking in the presence of actuator hysteresis and nonlinearities. Properties of the control design are illustrated through numerical examples.

  16. Hysteretic magnetoresistance and unconventional anomalous Hall effect in the frustrated magnet TmB4

    SciTech Connect

    Sunku, Sai Swaroop; Kong, Tai; Ito, Toshimitsu; Canfield, Paul C.; Shastry, B. Sriram; Sengupta, Pinaki; Panagopoulos, Christos

    2016-05-11

    We study TmB4, a frustrated magnet on the Archimedean Shastry-Sutherland lattice, through magnetization and transport experiments. The lack of anisotropy in resistivity shows that TmB4 is an electronically three-dimensional system. The magnetoresistance (MR) is hysteretic at low temperature even though a corresponding hysteresis in magnetization is absent. The Hall resistivity shows unconventional anomalous Hall effect (AHE) and is linear above saturation despite a large MR. In conclusion, we propose that complex structures at magnetic domain walls may be responsible for the hysteretic MR and may also lead to the AHE.

  17. Experimental and numerical study on hysteretic performance of SMA spring-friction bearings

    NASA Astrophysics Data System (ADS)

    Zhuang, Peng; Xue, Suduo; Nie, Pan; Wang, Wenting

    2016-12-01

    This paper presents an experimental and numerical study to investigate the hysteretic performance of a new type of isolator consisting of shape memory alloy springs and friction bearing called an SMA spring-friction bearing (SFB). The SFB is a sliding-type isolator with SMA devices used for the seismic protection of engineering structures. The principle of operation of the isolation bearing is introduced. In order to explore the possibility of applying SMA elements in passive seismic control devices, large diameter superelastic tension/compression NiTi SMA helical springs used in the SFB isolator were developed. Mechanical experiments of the SMA helical spring were carried out to understand its superelastic characteristics. After that, a series of quasi-static tests on a single SFB isolator prototype were conducted to measure its force-displacement relationships for different loading conditions and study the corresponding variation law of its mechanical performance. The experimental results demonstrate that the SFB exhibits full hysteretic curves, excellent energy dissipation capacity, and moderate recentering ability. Finally, a theoretical model capable of emulating the hysteretic behavior of the SMA-based isolator was then established and implemented in MATLAB software. The comparison of the numerical results with the experimental results shows the efficacy of the proposed model for simulating the response of the SFB.

  18. The hysteretic evapotranspiration - vapor pressure deficit relation

    NASA Astrophysics Data System (ADS)

    Zhang, Q.; Manzoni, S.; Katul, G. G.; Porporato, A. M.; Yang, D.

    2013-12-01

    Diurnal hysteresis between evapotranspiration (ET) and vapor pressure deficit (VPD) was reported in many ecosystems but justification for its onset and magnitude remain incomplete with biotic and abiotic factors invoked as possible explanations. To place these explanations within a mathematical framework, ';rate-dependent' hysteresis originating from a phase angle difference between periodic input and output time series is first considered. Lysimeter evaporation (E) measurements from wet bare soils and model calculations using the Penman equation demonstrate that the E-VPD hysteresis emerges without any biotic effects due to a phase angle difference (or time lag) between net radiation the main driver of E, and VPD. Modulations originating from biotic effects on the ET-VPD hysteresis were then considered. The phase angle difference representation earlier employed was mathematically transformed into a storage problem and applied to the soil-plant system. The transformed system shows that soil moisture storage within the root zone can produce an ET-VPD hysteresis prototypical of those generated by phase-angle differences. To explore the interplay between all the lags in the soil-plant-atmosphere system and phase angle differences among forcing and response variables, a detailed soil-plant-atmosphere continuum (SPAC) model was developed and applied to a grassland ecosystem. The results of the SPAC model suggest that the hysteresis magnitude depends on the radiation-VPD lag. The soil moisture dry-down simulations also suggest that modeled root water potential and leaf water potential are both better indicators of the hysteresis magnitude than soil moisture, suggesting that plant water status is the main factor regulating the hysteretic relation between ET and VPD. Hence, the genesis and magnitude of the ET-VPD hysteresis are controlled directly by both biotic factors and abiotic factors such as time lag between radiation and VPD originating from boundary layer processes

  19. Dynamic hysteretic sensing model of bending-mode Galfenol transducer

    SciTech Connect

    Cao, Shuying Zheng, Jiaju; Sang, Jie; Zhang, Pengfei; Wang, Bowen; Huang, Wenmei

    2015-05-07

    A dynamic hysteretic sensing model has been developed to predict the dynamic responses of the magnetic induction, the stress, and the output voltage for a bending-mode Galfenol unimorph transducer subjected simultaneously to acceleration and bias magnetic field. This model is obtained by coupling the hysteretic Armstrong model and the structural dynamic model of the Galfenol unimorph beam. The structural dynamic model of the beam is founded based on the Euler-Bernouli beam theory, the nonlinear constitutive equations, and the Faraday law of electromagnetic induction. Comparisons between the calculated and measured results show the model can describe dynamic nonlinear voltage characteristics of the device, and can predict hysteretic behaviors between the magnetic induction and the stress. Moreover, the model can effectively analyze the effects of the bias magnetic field, the acceleration amplitude, and frequency on the root mean square voltage of the device.

  20. Hysteretic resistance spikes in quantum hall ferromagnets without domains.

    PubMed

    Freire, Henrique J P; Egues, J Carlos

    2007-07-13

    We use spin-density-functional theory to study recently reported hysteretic magnetoresistance rho(xx) spikes in Mn-based 2D electron gases [Phys. Rev. Lett. 89, 266802 (2002)10.1103/PhysRevLett.89.266802]. We find hysteresis loops in our calculated Landau fan diagrams and total energies signaling quantum Hall ferromagnet phase transitions. Spin-dependent exchange-correlation effects are crucial to stabilize the relevant magnetic phases arising from distinct symmetry-broken excited- and ground-state solutions of the Kohn-Sham equations. Besides hysteretic spikes in rho(xx), we predict hysteretic dips in the Hall resistance rho(xy). Our theory, without domain walls, satisfactorily explains the recent data.

  1. Dynamic hysteretic sensing model of bending-mode Galfenol transducer

    NASA Astrophysics Data System (ADS)

    Cao, Shuying; Zheng, Jiaju; Sang, Jie; Zhang, Pengfei; Wang, Bowen; Huang, Wenmei

    2015-05-01

    A dynamic hysteretic sensing model has been developed to predict the dynamic responses of the magnetic induction, the stress, and the output voltage for a bending-mode Galfenol unimorph transducer subjected simultaneously to acceleration and bias magnetic field. This model is obtained by coupling the hysteretic Armstrong model and the structural dynamic model of the Galfenol unimorph beam. The structural dynamic model of the beam is founded based on the Euler-Bernouli beam theory, the nonlinear constitutive equations, and the Faraday law of electromagnetic induction. Comparisons between the calculated and measured results show the model can describe dynamic nonlinear voltage characteristics of the device, and can predict hysteretic behaviors between the magnetic induction and the stress. Moreover, the model can effectively analyze the effects of the bias magnetic field, the acceleration amplitude, and frequency on the root mean square voltage of the device.

  2. Hysteretic Behavior of Prestressed Concrete Bridge Pier with Fiber Model

    PubMed Central

    Hui-li, Wang; Guang-qi, Feng; Si-feng, Qin

    2014-01-01

    The hysteretic behavior and seismic characteristics of the prestressed concrete bridge pier were researched. The effects of the prestressed tendon ratio, the longitudinal reinforcement ratio, and the stirrup reinforcement ratio on the hysteretic behavior and seismic characteristics of the prestressed concrete bridge pier have been obtained with the fiber model analysis method. The analysis show some results about the prestressed concrete bridge pier. Firstly, greater prestressed tendon ratio and more longitudinal reinforcement can lead to more obvious pier's hysteresis loop “pinching effect,” smaller residual displacement, and lower energy dissipation capacity. Secondly, the greater the stirrup reinforcement ratio is, the greater the hysteresis loop area is. That also means that bridge piers will have better ductility and stronger shear capacity. The results of the research will provide a theoretical basis for the hysteretic behavior analysis of the prestressed concrete pier. PMID:24578635

  3. Hysteretic behavior of prestressed concrete bridge pier with fiber model.

    PubMed

    Wang, Hui-li; Feng, Guang-qi; Qin, Si-feng

    2014-01-01

    The hysteretic behavior and seismic characteristics of the prestressed concrete bridge pier were researched. The effects of the prestressed tendon ratio, the longitudinal reinforcement ratio, and the stirrup reinforcement ratio on the hysteretic behavior and seismic characteristics of the prestressed concrete bridge pier have been obtained with the fiber model analysis method. The analysis show some results about the prestressed concrete bridge pier. Firstly, greater prestressed tendon ratio and more longitudinal reinforcement can lead to more obvious pier's hysteresis loop "pinching effect," smaller residual displacement, and lower energy dissipation capacity. Secondly, the greater the stirrup reinforcement ratio is, the greater the hysteresis loop area is. That also means that bridge piers will have better ductility and stronger shear capacity. The results of the research will provide a theoretical basis for the hysteretic behavior analysis of the prestressed concrete pier.

  4. A novel practical control approach for rate independent hysteretic systems.

    PubMed

    Goforth, Frank J; Zheng, Qing; Gao, Zhiqiang

    2012-05-01

    A disturbance rejection based control approach, active disturbance rejection control (ADRC), is proposed for hysteretic systems with unknown characteristics. It is an appealing alternative to hysteresis compensation because it does not require a detailed model of hysteresis, by treating the nonlinear hysteresis as a common disturbance and actively rejecting it. The stability characteristic of the ADRC is analyzed. It is shown that, in the face of the inherent dynamic uncertainties, the estimation and closed-loop tracking errors of ADRC are bounded, with their bounds monotonously decreasing with the observer and controller bandwidths, respectively. Simulation results on a typical hysteretic system further demonstrate the effectiveness of the proposed approach.

  5. Hysteretic dynamics of active particles in a periodic orienting field

    PubMed Central

    Romensky, Maksym; Scholz, Dimitri; Lobaskin, Vladimir

    2015-01-01

    Active motion of living organisms and artificial self-propelling particles has been an area of intense research at the interface of biology, chemistry and physics. Significant progress in understanding these phenomena has been related to the observation that dynamic self-organization in active systems has much in common with ordering in equilibrium condensed matter such as spontaneous magnetization in ferromagnets. The velocities of active particles may behave similar to magnetic dipoles and develop global alignment, although interactions between the individuals might be completely different. In this work, we show that the dynamics of active particles in external fields can also be described in a way that resembles equilibrium condensed matter. It follows simple general laws, which are independent of the microscopic details of the system. The dynamics is revealed through hysteresis of the mean velocity of active particles subjected to a periodic orienting field. The hysteresis is measured in computer simulations and experiments on unicellular organisms. We find that the ability of the particles to follow the field scales with the ratio of the field variation period to the particles' orientational relaxation time, which, in turn, is related to the particle self-propulsion power and the energy dissipation rate. The collective behaviour of the particles due to aligning interactions manifests itself at low frequencies via increased persistence of the swarm motion when compared with motion of an individual. By contrast, at high field frequencies, the active group fails to develop the alignment and tends to behave like a set of independent individuals even in the presence of interactions. We also report on asymptotic laws for the hysteretic dynamics of active particles, which resemble those in magnetic systems. The generality of the assumptions in the underlying model suggests that the observed laws might apply to a variety of dynamic phenomena from the motion of

  6. Studying the hysteretic behaviour of unconsolidated sediments using an electroencephalography apparatus: a laboratory study.

    NASA Astrophysics Data System (ADS)

    Ruggeri, Paolo; Jougnot, Damien; Chavarriaga, Ricardo; Brandner, Catherine; del Rocio Millán Ruiz, José; Linde, Niklas

    2015-04-01

    In soil science, the hysteretic nature of the water retention curve plays an important role in describing a soil's propensity to retain water and conduct fluid flow. However, hysteresis effects remain difficult to study and to quantify. Geophysical methods provide suitable and non-invasive tools that could be used for this purpose. For example, the degree of water saturation in a soil can be determined by measuring its electrical resistivity, while a water flux through a soil generates a measureable electrical potential difference (streaming potential). The objective of this work is to study the hysteretic behaviour of unconsolidated sediments during repeated drainage and imbibition cycles under well-constrained laboratory conditions. Monitoring was performed using a 32-electrode electroencephalography (EEG) apparatus (Biosemi) coupled with a current injection system. We used a 150 cm high sand-filled column in which we monitored self-potential (SP) signals using 15 electrodes in direct contact with the medium (so-called "naked" electrodes), and 15 electrodes that were inserted in small porous pots that were filled with water of the same conductivity and chloride concentration as the water saturating the sand (so-called "chamber" electrodes). For both electrode types, the electrodes were placed between 5 and 145 cm height with an electrode spacing of 10 cm. Pressure (10 tensiometers) and mass, together with the temperature and the relative humidity in the room, were constantly monitored for the entire duration of the experiments. We performed ten cycles of drainage and imbibition by changing the water level of an external reservoir connected to the column. Each drainage and imbibition cycle took approximately 25 and 17 hours, respectively, for a total duration of the experiment of 24 days. After each imbibition and drainage cycle, we performed complex conductivity measurements by injecting a known electric current at two electrodes using a sine wave with varying

  7. Plane stress problems using hysteretic rigid body spring network models

    NASA Astrophysics Data System (ADS)

    Christos, Sofianos D.; Vlasis, Koumousis K.

    2016-08-01

    In this work, a discrete numerical scheme is presented capable of modeling the hysteretic behavior of 2D structures. Rigid Body Spring Network (RBSN) models that were first proposed by Kawai (Nucl Eng Des 48(1):29-207, 1978) are extended to account for hysteretic elastoplastic behavior. Discretization is based on Voronoi tessellation, as proposed specifically for RBSN models to ensure uniformity. As a result, the structure is discretized into convex polygons that form the discrete rigid bodies of the model. These are connected with three zero length, i.e., single-node springs in the middle of their common facets. The springs follow the smooth hysteretic Bouc-Wen model which efficiently incorporates classical plasticity with no direct reference to a yield surface. Numerical results for both static and dynamic loadings are presented, which validate the proposed simplified spring-mass formulation. In addition, they verify the model's applicability on determining primarily the displacement field and plastic zones compared to the standard elastoplastic finite element method.

  8. Comparing Extremal and Hysteretic Optimization on the Satisfiability Problem

    NASA Astrophysics Data System (ADS)

    Gonçalves, Bruno; Boettcher, Stefan

    2006-03-01

    We apply physically inspired optimization methods to the classical combinatorial Satisfiablity problem. Treating the usual boolean variables as Ising spins and each clause as a p-spin interaction we can use the pre-existing physical intuition about spin glasses and magnetic systems to find the optimal solution for this problem (the ground state energy). We compare the performance of Extremal OptimizationootnotetextPRL 23:5211, 2001 (τEO) and Hysteretic OptimizationootnotetextPRL 89:150201, 2002 (HO) and determine the parameter values that provide the best results. Comparisons with previously published results on well known benchmarksootnotetextDIMACS 35:393, 1997 are also made.

  9. Global adaptive control for uncertain nonaffine nonlinear hysteretic systems.

    PubMed

    Liu, Yong-Hua; Huang, Liangpei; Xiao, Dongming; Guo, Yong

    2015-09-01

    In this paper, the global output tracking is investigated for a class of uncertain nonlinear hysteretic systems with nonaffine structures. By combining the solution properties of the hysteresis model with the novel backstepping approach, a robust adaptive control algorithm is developed without constructing a hysteresis inverse. The proposed control scheme is further modified to tackle the bounded disturbances by adaptively estimating their bounds. It is rigorously proven that the designed adaptive controllers can guarantee global stability of the closed-loop system. Two numerical examples are provided to show the effectiveness of the proposed control schemes.

  10. Fast, Low-Power, Hysteretic Level-Detector Circuit

    NASA Technical Reports Server (NTRS)

    Arditti, Mordechai

    1993-01-01

    Circuit for detection of preset levels of voltage or current intended to replace standard fast voltage comparator. Hysteretic analog/digital level detector operates at unusually low power with little sacrifice of speed. Comprises low-power analog circuit and complementary metal oxide/semiconductor (CMOS) digital circuit connected in overall closed feedback loop to decrease rise and fall times, provide hysteresis, and trip-level control. Contains multiple subloops combining linear and digital feedback. Levels of sensed signals and hysteresis level easily adjusted by selection of components to suit specific application.

  11. Hysteretic memory and end plate effects on the response of a flexible cylinder undergoing Vortex-Induced Vibrations (VIV)

    NASA Astrophysics Data System (ADS)

    Gedikli, Ersegun Deniz; Dahl, Jason M.

    2015-11-01

    The response of rigid cylinders undergoing VIV has been observed to be hysteretic with respect to the nominal reduced velocity, as transition of the wake is delayed dependent on whether the flow has been slowed down or sped up. In the present study, a similar behavior is observed for a flexible, tension-dominated cylinder, however the hysteretic behavior is shown to affect the transition between excited modes. The test cylinder has diameter of 6.35 mm, aspect ratio of 40 and mass ratio of 3.76. The dynamic response of the cylinder is measured visually, by tracking 26 dots along the span of the cylinder using two high-speed cameras between the Reynolds number of 1080 and 4660. It is observed that a clear memory effect exists, where the speed at which transition between the first mode and second mode excitation in the cross-flow direction changes dependent on whether the flow is increasing or decreasing in speed. A second series of experiments is conducted to investigate end plate effects on the flexible cylinder. Experiments are conducted with and without an end plate located at the end pivot point on the cylinder. Clear differences are observed between each condition illustrating the strong three-dimensional behavior of vortex shedding behind the flexible cylinder.

  12. Calibration of a hysteretic model for glass fiber reinforced gypsum wall panels

    NASA Astrophysics Data System (ADS)

    Janardhana, Maganti; Robin Davis, P.; Ravichandran, S. S.; Prasad, A. M.; Menon, D.

    2014-06-01

    Glass fiber reinforced gypsum (GFRG) wall panels are prefabricated panels with hollow cores, originally developed in Australia and subsequently adopted by India and China for use in buildings. This paper discusses identification and calibration of a suitable hysteretic model for GFRG wall panels filled with reinforced concrete. As considerable pinching was observed in the experimental results, a suitable hysteretic model with pinched hysteretic rule is used to conduct a series of quasi-static as inelastic hysteretic response analyses of GFRG panels with two different widths. The calibration of the pinching model parameters was carried out to approximately match the simulated and experimental responses up to 80% of the peak load in the post peak region. Interestingly, the same values of various parameters (energy dissipation and pinching related parameters) were obtained for all five test specimens.

  13. Vibration analysis of nonlinear systems with the bilinear hysteretic oscillator by using incremental harmonic balance method

    NASA Astrophysics Data System (ADS)

    Xiong, Huai; Kong, Xianren; Li, Haiqin; Yang, Zhenguo

    2017-01-01

    This paper considers dynamics of bilinear hysteretic systems, which are widely used for vibration control and vibration absorption such as magneto-rheological damper, metal-rubber. The method of incremental harmonic balance (IHB) technique that hysteresis is considered in the corrective term is improved in order to determine periodic solutions of bilinear hysteretic systems. The improved continuation method called two points tracing algorithm which is stable to the turning point makes the calculation more efficient for tracing amplitude-frequency response. Precise Hsu's method for analysing the stability of periodic solutions is introduced. The effects of different parameters of bilinear hysteretic oscillator on the response are discussed numerically. Some numerical simulations of considered bilinear hysteretic systems, including a single DOF and a 2DOF system, are effectively obtained by the modified IHB method and the results compare very well with the 4-oder Runge-Kutta method.

  14. Transverse hysteretic damping characteristics of a serpentine belt: Modeling and experimental investigation

    NASA Astrophysics Data System (ADS)

    Zhu, Hao; Hu, Yumei; Pi, Yangjun

    2014-12-01

    In this paper, the transverse dynamic hysteretic damping characteristics (HDC) of a serpentine belt are investigated. The variable stiffness and variable damping model (VSDM) constituted of a variable-stiffness spring and a variable-damping damper is developed to estimate the HDC of the belt. A test rig is designed to test the force-displacement hysteresis damping curve and resonance frequencies of serpentine belts with different lengths under diverse loading conditions. The force-displacement hysteresis damping curve getting from the experiment is then used to determine the transverse stiffness and damping coefficients needed for the VSDM. The experiment particularly shows that the orientation of the hysteresis curve swings left and right around each natural frequency as it is a symmetrical point. This interesting phenomenon is explicated in detail with the loss angle which is calculated by two methods. Moreover, two sub-analytical models included in the VSDM are proposed to model the dependence of transverse dynamic stiffness and damping coefficient of a belt on belt length, pretension and excitation frequency. A comparison of the hysteresis curves obtained from the VSDM and experiment indicates that they are in good agreement.

  15. Research on strip hysteretic behavior and mill vertical vibration system nonlinear dynamics

    NASA Astrophysics Data System (ADS)

    Fan, Xiaobin; Zang, Yong; Jin, Ke

    2016-10-01

    Rolling mill vibration is a technical problem in the iron and steel industry for many years and has serious impact and harm on production. There were serious vibrations in the middle mills when rolling thin container strip for the compact strip production (CSP) strip hot rolling process. This paper studied the hysteretic characteristic of rolled strip and established the vertical vibration system single-degree-of-freedom dynamics model of the F3 mill rollers. The influence of parameters on the system characteristics was studied, such as the linear damping coefficient, linear stiffness coefficient, nonlinear displacement coefficient, nonlinear velocity coefficient and exciting force, and then, the vibration source and vibration-restraining measure were studied from the roll gap. The results show that with increasing linear stiffness, damping and hysteresis coefficient, it can reduce the possibility of chaotic system; the linear stiffness coefficient had the greatest influence, and hysteresis damping coefficient had minimal influence on chaotic threshold. In order to reduce rolling mill vibration amplitude, we should reduce the external excitation force firstly, and in order to improve the dynamic performance of the system, we should control the speed of nonlinear coefficient values. The contrast experiments were carried out at the production scene finally.

  16. Periodic reference tracking control approach for smart material actuators with complex hysteretic characteristics

    NASA Astrophysics Data System (ADS)

    Sun, Zhiyong; Hao, Lina; Song, Bo; Yang, Ruiguo; Cao, Ruimin; Cheng, Yu

    2016-10-01

    Micro/nano positioning technologies have been attractive for decades for their various applications in both industrial and scientific fields. The actuators employed in these technologies are typically smart material actuators, which possess inherent hysteresis that may cause systems behave unexpectedly. Periodic reference tracking capability is fundamental for apparatuses such as scanning probe microscope, which employs smart material actuators to generate periodic scanning motion. However, traditional controller such as PID method cannot guarantee accurate fast periodic scanning motion. To tackle this problem and to conduct practical implementation in digital devices, this paper proposes a novel control method named discrete extended unparallel Prandtl-Ishlinskii model based internal model (d-EUPI-IM) control approach. To tackle modeling uncertainties, the robust d-EUPI-IM control approach is investigated, and the associated sufficient stabilizing conditions are derived. The advantages of the proposed controller are: it is designed and represented in discrete form, thus practical for digital devices implementation; the extended unparallel Prandtl-Ishlinskii model can precisely represent forward/inverse complex hysteretic characteristics, thus can reduce modeling uncertainties and benefits controllers design; in addition, the internal model principle based control module can be utilized as a natural oscillator for tackling periodic references tracking problem. The proposed controller was verified through comparative experiments on a piezoelectric actuator platform, and convincing results have been achieved.

  17. Experimental demonstration of a damage detection technique for nonlinear hysteretic structures

    NASA Astrophysics Data System (ADS)

    Yang, Jann N.; Xia, Ye; Loh, Chin-Hsiung

    2011-04-01

    Many civil and mechanical engineering structures exhibit nonlinear hysteretic behavior when subject to dynamic loads, such as earthquakes. The modeling and identification of non-linear hysteretic systems with stiffness and strength degradations is a practical but challenging problem encountered in the engineering field. A recently developed technique, referred to as the adaptive quadratic sum-square error with unknown inputs (AQSSE-UI), is capable of identifying time dependant parameters of nonlinear hysteretic structures. In this paper, the AQSSE-UI technique is applied to the parametric identification of nonlinear hysteretic reinforced concrete structures with stiffness and strength degradations, and the performance of the AQSSE technique is demonstrated by the experimental test data. A 1/3 scaled 2-story RC frame has been tested experimentally on the shake table at NCREE, Taiwan. This 2-story RC frame was subject to different levels of ground excitations back to back. The structure is firstly considered as an equivalent linear model with time-varying stiffness parameters, and the tracking of the degradation of the stiffness parameters is carried out using the AQSSE-UI technique. Then the same RC frame is considered as a nonlinear hysteretic model with inelastic hinges following the generalized Bouc-Wen model, and the time-varying nonlinear parameters are identified again using the AQSSE-UI technique. Experimental results demonstrate that the AQSSE technique is quite effective for the tracking of: (i) the stiffness degradation of linear structures, and (ii) the non-linear hysteretic parameters with stiffness and strength degradations.

  18. Spatial, Hysteretic, and Adaptive Host-Guest Chemistry in a Metal-Organic Framework with Open Watson-Crick Sites.

    PubMed

    Cai, Hong; Li, Mian; Lin, Xiao-Rong; Chen, Wei; Chen, Guang-Hui; Huang, Xiao-Chun; Li, Dan

    2015-09-01

    Biological and artificial molecules and assemblies capable of supramolecular recognition, especially those with nucleobase pairing, usually rely on autonomous or collective binding to function. Advanced site-specific recognition takes advantage of cooperative spatial effects, as in local folding in protein-DNA binding. Herein, we report a new nucleobase-tagged metal-organic framework (MOF), namely ZnBTCA (BTC=benzene-1,3,5-tricarboxyl, A=adenine), in which the exposed Watson-Crick faces of adenine residues are immobilized periodically on the interior crystalline surface. Systematic control experiments demonstrated the cooperation of the open Watson-Crick sites and spatial effects within the nanopores, and thermodynamic and kinetic studies revealed a hysteretic host-guest interaction attributed to mild chemisorption. We further exploited this behavior for adenine-thymine binding within the constrained pores, and a globally adaptive response of the MOF host was observed.

  19. Multilevel radiative thermal memory realized by the hysteretic metal-insulator transition of vanadium dioxide

    SciTech Connect

    Ito, Kota Nishikawa, Kazutaka; Iizuka, Hideo

    2016-02-01

    Thermal information processing is attracting much interest as an analog of electronic computing. We experimentally demonstrated a radiative thermal memory utilizing a phase change material. The hysteretic metal-insulator transition of vanadium dioxide (VO{sub 2}) allows us to obtain a multilevel memory. We developed a Preisach model to explain the hysteretic radiative heat transfer between a VO{sub 2} film and a fused quartz substrate. The transient response of our memory predicted by the Preisach model agrees well with the measured response. Our multilevel thermal memory paves the way for thermal information processing as well as contactless thermal management.

  20. Multilevel radiative thermal memory realized by the hysteretic metal-insulator transition of vanadium dioxide

    NASA Astrophysics Data System (ADS)

    Ito, Kota; Nishikawa, Kazutaka; Iizuka, Hideo

    2016-02-01

    Thermal information processing is attracting much interest as an analog of electronic computing. We experimentally demonstrated a radiative thermal memory utilizing a phase change material. The hysteretic metal-insulator transition of vanadium dioxide (VO2) allows us to obtain a multilevel memory. We developed a Preisach model to explain the hysteretic radiative heat transfer between a VO2 film and a fused quartz substrate. The transient response of our memory predicted by the Preisach model agrees well with the measured response. Our multilevel thermal memory paves the way for thermal information processing as well as contactless thermal management.

  1. COMPARING SIMULATED AND EXPERIMENTAL HYSTERETIC TWO- PHASE TRANSIENT FLUID FLOW PHENOMENA

    EPA Science Inventory

    A hysteretic model for two-phase permeability (k)-saturation (S)-pressure (P) relations is outlined that accounts for effects of nonwetting fluid entrapment. The model can be employed in unsaturated fluid flow computer codes to predict temporal and spatial fluid distributions. Co...

  2. An improved PSO algorithm for parameter identification of nonlinear dynamic hysteretic models

    NASA Astrophysics Data System (ADS)

    Zhang, Junhao; Xia, Pinqi

    2017-02-01

    The nonlinear dynamic hysteretic models used in nonlinear dynamic analysis contain generally lots of model parameters which need to be identified accurately and effectively. The accuracy and effectiveness of identification depend generally on the complexity of model, number of model parameters and proximity of initial values of the parameters. The particle swarm optimization (PSO) algorithm has the random searching ability and has been widely applied to the parameter identification in the nonlinear dynamic hysteretic models. However, the PSO algorithm may get trapped in the local optimum and appear the premature convergence not to obtain the real optimum results. In this paper, an improved PSO algorithm for identifying parameters of nonlinear dynamic hysteretic models has been presented by defining a fitness function for hysteretic model. The improved PSO algorithm can enhance the global searching ability and avoid to appear the premature convergence of the conventional PSO algorithm, and has been applied to identify the parameters of two nonlinear dynamic hysteretic models which are the Leishman-Beddoes (LB) dynamic stall model of rotor blade and the anelastic displacement fields (ADF) model of elastomeric damper which can be used as the lead-lag damper in rotor. The accuracy and effectiveness of the improved PSO algorithm for identifying parameters of the LB model and the ADF model are validated by comparing the identified results with test results. The investigations have indicated that in order to reduce the influence of randomness caused by using the PSO algorithm on the accuracy of identified parameters, it is an effective method to increase the number of repeated identifications.

  3. A quasi-modal parameter based system identification procedure with non-proportional hysteretic damping

    NASA Astrophysics Data System (ADS)

    Yu, Minli; Hahn, Eric J.; Liu, Jike; Lu, Zhongrong

    2016-11-01

    This paper introduced a modal parameter based identification procedure to identify the equivalent system of structures under harmonic excitations. The developed identification technique assumed non-proportional hysteretic damping in the equivalent system, which would be applicable in identifying more general structures. By introducing quasi-modal parameter, modal analysis equation was decoupled under physical coordinate; hence, the modal parameters of each vibration mode are identified independently. Double iteration algorithm was developed to solve the derived non-linear identification equation with complex unknowns. The developed identification procedure was applied to identify the equivalent system of a numerical model in order to evaluate the feasibility of the technique in practice. The identification procedure was also applied to identify an experimental mass and bar rig for validation purpose. Identification results showed that the identification procedure could identify accurately and robustly the equivalent system with non-proportional hysteretic damping assumption; hence, it is likely to be applicable in the field.

  4. User's Guide for Hysteretic Capillary Pressure and Relative Permeability Functions in TOUGH2

    SciTech Connect

    Doughty, C. A.

    2013-03-01

    This document provides a user’s guide for the most recent version of the hysteretic code, which runs within iTOUGH2 (Finsterle, 1999a,b,c) or TOUGH2 V2.1 (Pruess et al., 2012). The usage of the hysteretic module is the same in both codes, which for brevity here are both referred to simply as TOUGH2. The current code differs only slightly from what was presented in Doughty (2007), hence that document provides the basic information on the processes being modeled and how they are conceptualized. This document focuses on a description of the user-specified parameters required to run hysteretic TOUGH2. In the few instances where the conceptualization differs from that of Doughty (2007), the features described here are the current ones. Sample problems presented in this user’s guide use the equation-of-state module ECO2N (Pruess, 2005). The components present in ECO2N are H{sub 2}O, NaCl, and CO{sub 2}. Two fluid phases and one solid phase are considered: an aqueous phase, which primarily consists of liquid H{sub 2}O and may contain dissolved NaCl and CO{sub 2}; a supercritical phase which primarily consists of CO{sub 2}, but also includes a small amount of gaseous H{sub 2}O; and a solid phase consisting of precipitated NaCl. Details of the ECO2N formulation may be found in Pruess (2005). The aqueous phase is the wetting phase and is denoted ‘liquid’, whereas the supercritical phase is the non-wetting phase and is denoted ‘gas’. The hysteretic formalism may be applied to other TOUGH2 equation-of-state modules that consider two fluid phases, as long as the liquid phase is the wetting phase and the gas phase is the non-wetting phase.

  5. Hysteretic patterns of suspended sediment discharge in a glacierized Andean catchment

    NASA Astrophysics Data System (ADS)

    Mao, L.; Carrillo, R.; Escauriaza, C. R.

    2014-12-01

    Sediment transport during flood events often reveals hysteretic patterns. Hysteresis can be clockwise (when flow discharge peaks after the peak of bedload) or counterclockwise (when flow discharge peaks before the peak of bedload), and recent indexes have been developed in order to quantify the degree of hysteretic patterns. Hysteresis patterns and degree can be used to infer the dynamics of sediment availability, as counterclockwise and clockwise hysteresis have been interpreted as representative of limited and unlimited sediment supply conditions, respectively. This work focuses on the temporal variability of suspended sediment transport measured in the Estero Morales, a 27 km2 Andean catchment located in central Chile. The elevations range from 1850 m a.s.l to 3815 m a.s.l., and the basin host glaciers with a current extent of 1.8 km2. Runoff is dominated by snowmelt in late spring, and glacier melt from December to March. Liquid discharge and turbidity have been measured continuously from October 2013 to March 2014. The analysis of hysteretic loops of daily discharge fluctuations of spring and summer shows that patterns are mostly clockwise during snowmelt and early glacier melt period, and counterclockwise during late glacier melting, revealing a reduction of sediment supply conditions overtime. This is confirmed by the analysis of regressions between liquid discharge and turbidity, revealing that a higher discharge is progressively needed to transport the same concentration of suspended sediments as the glacier melting season progress. These evidences indicate that suspended sediment transport in glacierized basins is affected by complex interactions among runoff generation, and sediment availability, and that the analysis of temporal hysteresis can help inferring the activity of sediment sources at the basin scale. The research was supported by the projects FONDECYT 1130378 and IDRC 107081-00.

  6. Propagation of flexural waves in inhomogeneous plates exhibiting hysteretic nonlinearity: Nonlinear acoustic black holes.

    PubMed

    Gusev, Vitalyi E; Ni, Chenyin; Lomonosov, Alexey; Shen, Zhonghua

    2015-08-01

    Theory accounting for the influence of hysteretic nonlinearity of micro-inhomogeneous material on flexural wave in the plates of continuously varying thickness is developed. For the wedges with thickness increasing as a power law of distance from its edge strong modifications of the wave dynamics with propagation distance are predicted. It is found that nonlinear absorption progressively disappearing with diminishing wave amplitude leads to complete attenuation of acoustic waves in most of the wedges exhibiting black hole phenomenon. It is also demonstrated that black holes exist beyond the geometrical acoustic approximation. Applications include nondestructive evaluation of micro-inhomogeneous materials and vibrations damping.

  7. Negative differential conductance and hysteretic current switching of benzene molecular junction in a transverse electric field

    NASA Astrophysics Data System (ADS)

    Zhu, Wen-Huan; Ding, Guo-Hui; Dong, Bing

    2014-11-01

    We study charge transport through single benzene molecular junction (BMJ) directly sandwiched between two platinum electrodes by using a tight-binding model and the non-equilibrium Green's function approach. Pronounced negative differential conductance is observed at finite bias voltage, resulting from charge redistribution in BMJ and a Coulomb blockade effect at the interface of molecule-electrode contacts. In the presence of a transverse electric field, hysteretic switching behavior and large spin-polarization of current are obtained, indicating the potential application of BMJ for acting as a nanoscale current modulator or spintronic molecular device.

  8. Hysteretic effects in the first-order irreversible phase transition of the ZGB model

    NASA Astrophysics Data System (ADS)

    Loscar, Ernesto S.; Albano, Ezequiel V.

    2009-04-01

    The first-order irreversible phase transition (FOIPT) of the ZGB model [Ziff, Gulari, Barshad, Phys. Rev. Lett. 56 (1986) 2553] for the catalytic oxidation of carbon monoxide is studied numerically by using the constant-coverage (CC) ensemble. The CC method allows us to study hysteretic effects close to coexistence, as well as the location of the coexistence point. Also, evidence that the FOIPT exhibits a condensation/evaporation pseudo-transition (in finite samples), as observed in its reversible counterparts, is presented and discussed.

  9. Enhancement of harmonics generation in hysteretic elastic media induced by conditioning

    NASA Astrophysics Data System (ADS)

    Mechri, C.; Scalerandi, M.; Bentahar, M.

    2017-04-01

    The physical origin of harmonics generation in non classical (hysteretic) elastic media and the mechanisms of energy transfer among harmonics are still not completely understood. Furthermore the well known conditioning effect observed in such materials is known to have a significant influence on the elastic response of consolidated granular media and damaged composites and metals. Here, we show that the elastic non linearity of samples belonging to these two categories increases after having been excited with a relatively low amplitude stress. The observed behaviours could be described by activation features intrinsically present in phenomenological multistate models proposed in the literature.

  10. Spatially Extended Avalanches in a Hysteretic Capillary Condensation System: Superfluid {sup {bold 4}}He in Nuclepore

    SciTech Connect

    Lilly, M.P.; Wootters, A.H.; Hallock, R.B.

    1996-11-01

    Capacitive studies of hysteretic capillary condensation of superfluid {sup 4}He in Nuclepore have shown that the initial draining of the pores occurs over a small range of the chemical potential with avalanches present as groups of pores drain. In the work reported here, the avalanches in this system are shown to be nonlocal events which involve pores distributed at low density across the entire sample. The nonlocal avalanche behavior is shown to be enabled by the presence of a superfluid film connection among the pores. {copyright} {ital 1996 The American Physical Society.}

  11. Creep-free ac hysteretic dynamics in epitaxial ferroelectric BiFeO3 films

    NASA Astrophysics Data System (ADS)

    Shin, Yeongjae; Jeon, Byung Chul; Yang, Sang Mo; Hwang, Inrok; Cho, Myung Rae; Sando, Daniel; Lee, Seung Ran; Yoon, Jong-Gul; Noh, Tae Won

    2015-03-01

    Dynamics of domain wall (DW) in ferroelectric (FE) films principally governs their switching properties under applied electric field (E) . At finite temperature (T) , the DW motion and their FE switching characteristics can be understood only by introducing the creep motion. Despite this importance, there have been little studies on creep motion of FE films under ac-driven force. In this work, we investigate ac-driven hysteretic dynamics of FE domains in epitaxial BiFeO3 (BFO) films through polarization-electric field hysteresis loops with varying frequency and other switching characters. All BFO films were grown at the optimized growth condition, by employing different bottom electrodes of La0.67Sr0.33MnO3 (LSMO) and SrRuO3 (SRO); only BFO/SRO shows nearly creep-free hysteretic dynamics. We argue that inhomogeneous internal E plays a significant role in such distinctive FE dynamics of BFO domains, which are affected by surface morphologies of bottom electrodes. Our results highlight that growth-mode-induced interfacial structure between an FE film and a bottom electrode result in engineering domain dynamics of FE switching characteristics. This work was supported by IBS-R009-D1.

  12. First passage times in M2[X ]|G |1 |R queue with hysteretic overload control policy

    NASA Astrophysics Data System (ADS)

    Pechinkin, Alexander V.; Razumchik, Rostislav R.; Zaryadov, Ivan S.

    2016-06-01

    One of the reported approaches towards the solution of overload problem in networks of SIP servers is the implementation of multi-level hysteretic control of arrivals in SIP servers. Each level, being the parameter of the policy, specifies operation mode of SIP server i.e. it implicitly indicates what SIP server must do with the arriving packets. The choice of parameters' values is not guided by standards and is usually left for the network owner. In general, all operation modes of the considered policy can be grouped into two groups: normal mode (when all arriving packets are accepted) and congested mode (when part or all arriving packets are being dropped). Such grouping may serve as the criteria for choosing parameters' values of the policy: pick those values which minimize SIP server sojourn time in congested mode. In this short note we propose some analytical results which facilitate the solution of stated minimization problem. The considered mathematical model of SIP server is the queueing system M2[X ]|G |1 |R with batch arrivals and bi-level hysteretic control policy, which specifies three operation modes: normal (customers both flows are accepted), overload (only customers from one flow are accepted), discard (customers from both flows are blocked/lost)). The switching between modes can occur only on service completions. Analytical method allowing computation of stationary sojourn times in different operation modes (as well as first passage times between modes) is presented in brief. Numerical example is given.

  13. An alternative measurement tool for the identification of hysteretic responses in biological joints.

    PubMed

    Borkowski, Sean L; Sangiorgio, Sophia N; Ebramzadeh, Edward; Masri, Sami F

    2014-11-01

    In structural engineering, sophisticated multi-dimensional analysis techniques, such as the Restoring Force Method (RFM), have been established for complex, nonlinear hysteretic systems. The purpose of the present study was to apply the RFM to quantify nonlinear spine hysteresis responses under applied moments. First, synthetic hysteretic spine responses (n=50) were generated based on representative results from pure moment flexion-extension loading of a human cadaveric lumbar spine segment. Then, the RFM was applied to each hysteresis response to describe the flexion-extension rotation as a function of applied moment and simulated axial displacement using a set of 16 unique coefficients. Range of motion, neutral zone, elastic zone, and stiffness were also measured. The RFM coefficient corresponding to the 1st-order linear dependence of rotation on applied moment was dominant, and paralleled changes in elastic zone. The remaining RFM coefficients were not captured from the traditional biomechanical analysis. Therefore, the RFM may potentially supplement the traditional analysis to develop a more comprehensive, quantitative description of spine hysteresis. The results suggest the potential for more thorough and specific characterization of spine kinematics, and may lead to future applications of such techniques in characterizing biological structures.

  14. Hysteretic Behavior of Proprotein Convertase 1/3 (PC1/3)

    PubMed Central

    Icimoto, Marcelo Y.; Barros, Nilana M.; Ferreira, Juliana C.; Marcondes, Marcelo F.; Andrade, Douglas; Machado, Mauricio F.; Juliano, Maria A.; Júdice, Wagner A.; Juliano, Luiz; Oliveira, Vitor

    2011-01-01

    The proprotein convertases (PCs) are calcium-dependent proteases responsible for processing precursor proteins into their active forms in eukariotes. The PC1/3 is a pivotal enzyme of this family that participates in the proteolytic maturation of prohormones and neuropeptides inside the regulated secretory pathway. In this paper we demonstrate that mouse proprotein convertase 1/3 (mPC1/3) has a lag phase of activation by substrates that can be interpreted as a hysteretic behavior of the enzyme for their hydrolysis. This is an unprecedented observation in peptidases, but is frequent in regulatory enzymes with physiological relevance. The lag phase of mPC1/3 is dependent on substrate, calcium concentration and pH. This hysteretic behavior may have implications in the physiological processes in which PC1/3 participates and could be considered an additional control step in the peptide hormone maturation processes as for instance in the transformation of proinsulin to insulin. PMID:21935423

  15. Numerical Simulation of Hysteretic Live Load Effect in a Soil-Steel Bridge

    NASA Astrophysics Data System (ADS)

    Sobótka, Maciej

    2014-03-01

    The paper presents numerical simulation of hysteretic live load effect in a soil-steel bridge. The effect was originally identified experimentally by Machelski [1], [2]. The truck was crossing the bridge one way and the other in the full-scale test performed. At the same time, displacements and stress in the shell were measured. The major conclusion from the research was that the measured quantities formed hysteretic loops. A numerical simulation of that effect is addressed in the present work. The analysis was performed using Flac finite difference code. The methodology of solving the mechanical problems implemented in Flac enables us to solve the problem concerning a sequence of load and non-linear mechanical behaviour of the structure. The numerical model incorporates linear elastic constitutive relations for the soil backfill, for the steel shell and the sheet piles, being a flexible substructure for the shell. Contact zone between the shell and the soil backfill is assumed to reflect elastic-plastic constitutive model. Maximum shear stress in contact zone is limited by the Coulomb condition. The plastic flow rule is described by dilation angle ψ = 0. The obtained results of numerical analysis are in fair agreement with the experimental evidence. The primary finding from the performed simulation is that the slip in the interface can be considered an explanation of the hysteresis occurrence in the charts of displacement and stress in the shell.

  16. Hysteretic Performance Identification for a Frame Structure with MR Damper under Limited Excitations

    NASA Astrophysics Data System (ADS)

    Xu, Bin; Zhou, Ren; He, Jia; Masri, Sami F.

    2010-05-01

    Nonlinearity exists widely in engineering structures and may arise in damaged structures, but the identification theory for nonlinear dynamic systems is far less established than that for linear systems. Most of the currently available vibration-based identification approaches for structural damage detection are based on eigenvalues and mode shapes extraction which are suitable for linear systems. For the purpose of early warning and damage prognosis, it is crucial to develop efficient and reliable identification methods for nonlinear hysteretic performance because the restoring force is the direct indicator of damage initiation and development. In this paper, a general time series data-based approach was employed to identify the nonlinear behavior of a multi-degree-of-freedom frame structure equipped with a MR damper only using the excitation force applied on limited locations and the corresponding structural response measurement. The performance of the proposed methodology was validated for a 4-story frame model structure with and without a MR damper. The system matrices of the linear frame model structure were identified firstly with a least-squares techniques and the equivalent system of the frame structure with MR damper were identified. Then the location and the hysteretic performance of the MR damper were identified and compared with the test measurements. Results show that the proposed data-based approach is efficient for nonlinear behavior identification of engineering structures.

  17. Hysteretic behavior of special shaped columns composed of steel and reinforced concrete (SRC)

    NASA Astrophysics Data System (ADS)

    Chen, Zongping; Xu, Jinjun; Xue, Jianyang

    2015-06-01

    This paper describes a series of experimental investigations on seventeen specimens of steel reinforced concrete special shaped (SRCSS) columns under low cyclic reversed loading using parallel crosshead equipment. Nine T-shaped SRC columns, four L-shaped SRC columns and four +-shaped SRC columns were tested to examine the effects of shape steel configuration, loading angle, axial compressive ratio and shear-span ratio on the behavior (strength, stiffness, energy dissipation, ductility, etc.) of SRCSS column specimens. The failure modes and hysteretic performance of all the specimens were obtained in the tests. Test results demonstrate that the shear-span ratio is the main parameter affecting the failure modes of SRCSS columns. The specimens with small shear-span ratio are prone to shear failure, and the primary failure planes in SRCSS columns are parallel to the loading direction. As a result, there is a symmetry between positive and negative loading directions in the hysteretic curves of the SRCSS columns. The majority of displacement ductility coefficients for all the specimens are over 3.0, so that the SRCSS columns demonstrate a better deformation capacity. In addition, the equivalent viscous damping coefficients of all the specimens are greater than 0.2, indicating that the seismic behavior of SRCSS columns is adequate. Finally, the superposition theory was used to calculate the limits of axial compressive ratio for the specimens, and it is found that the test axial compressive ratio is close to or smaller than the calculated axial compressive ratio limit.

  18. INDIRECT INTELLIGENT SLIDING MODE CONTROL OF A SHAPE MEMORY ALLOY ACTUATED FLEXIBLE BEAM USING HYSTERETIC RECURRENT NEURAL NETWORKS

    PubMed Central

    Hannen, Jennifer C.; Crews, John H.; Buckner, Gregory D.

    2012-01-01

    This paper introduces an indirect intelligent sliding mode controller (IISMC) for shape memory alloy (SMA) actuators, specifically a flexible beam deflected by a single offset SMA tendon. The controller manipulates applied voltage, which alters SMA tendon temperature to track reference bending angles. A hysteretic recurrent neural network (HRNN) captures the nonlinear, hysteretic relationship between SMA temperature and bending angle. The variable structure control strategy provides robustness to model uncertainties and parameter variations, while effectively compensating for system nonlinearities, achieving superior tracking compared to an optimized PI controller. PMID:22962538

  19. On Response of a Single-Degree-of-Freedom Oscillator with Constant Hysteretic Damping Under Arbitrary Excitation

    NASA Astrophysics Data System (ADS)

    Chakraborty, Goutam

    2016-10-01

    The simple constant hysteretic damping model is known to be non-causal although it is used often in diverse branches of engineering. In this paper the response of a single degree of freedom oscillator having linear hysteretic damping under arbitrary force excitation has been studied after deriving the impulse response function of the system. Some shortcomings of the results available in literature have been pointed out. It has been shown that the damping model can be practically used for calculating the response of a physical system when the damping is small and the force has small duration.

  20. Repetitive Control for Hysteretic Systems: Theory and Application in Piezo-Based Nanopositioners

    NASA Astrophysics Data System (ADS)

    Shan, Yingfeng

    This dissertation studies the design and analysis of repetitive controllers for hysteretic systems. An example hysteretic system is a piezoelectric actuator (piezoactuator), the workhorse of actuators used for positioning and manipulating objects and tools at the micro and nano scale. For example, in scanning probe microscopes (SPMs) a piezoactuator is used to raster (back and forth in a repetitive fashion) a probe tool with sub-nanometer precision relative to a sample surface for imaging, manipulating, and fabricating organic or inorganic nano-scale features. Likewise, piezoactuators are used to position optics in space telescopes and tools in micro-machining systems. Despite their importance, piezoactuators exhibit hysteresis effect, a nonlinear behavior between the applied input voltage and the resulting output displacement of the piezoactuator. If left uncompensated for, hysteresis (and dynamic effects) cause positioning error that significantly limits the performance of piezo-based positioning systems. Repetitive control, a feedback-based approach which exploits the process of repetition, is commonly applied to track periodic reference trajectories and/or to reject periodic disturbances. The major challenges in the design of RC are closed-loop stability, robustness, and minimizing the steady-state tracking error. For hysteretic systems such as piezo-based nanopositioners, the nonlinearity can drastically limit the performance of RC designed around a linear dynamics model. In this work, the effect of hysteresis on the closed-loop stability of RC is analyzed and the allowable size of the hysteresis nonlinearity for a stable RC is quantified. In the stability analysis, the bounded-input bounded-output (BIBO) stability of the repetitive controlled hysteretic system in the L2 -norm sense is shown. Combining this result with the Small-Gain Theorem, an acceptable size of the hysteresis nonlinearity is determined that guarantees closed-loop stability. Therefore, one

  1. Modeling the nonlinear hysteretic response in DAE experiments of Berea sandstone: A case-study

    SciTech Connect

    Pecorari, Claudio

    2015-03-31

    Dynamic acousto-elasticity (DAE) allows probing the instantaneous state of a material while the latter slowly and periodically is changed by an external, dynamic source. In DAE investigations of geo-materials, hysteresis of the material's modulus defect displays intriguing features which have not yet been interpreted in terms of any specific mechanism occurring at atomic or mesoscale. Here, experimental results on dry Berea sandstone, which is the rock type best investigated by means of a DAE technique, are analyzed in terms of three rheological models providing simplified representations of mechanisms involving dislocations interacting with point defects which are distributed along the dislocations' core or glide planes, and microcracks with finite stiffness in compression. Constitutive relations linking macroscopic strain and stress are derived. From the latter, the modulus defect associated to each mechanism is recovered. These models are employed to construct a composite one which is capable of reproducing several of the main features observed in the experimental data. The limitations of the present approach and, possibly, of the current implementation of DAE are discussed.

  2. The sulphatase of ox liver. XXV. Sulphatase A as a hysteretic enzyme.

    PubMed

    Roy, A B

    1985-01-21

    The kinetic behaviour of the system native--substrate-modified sulphatase A (arylsulphate sulphohydrolase, EC 3.1.6.1) has been investigated and it has been shown that the progress curve of the complete reaction, including both the inactivation and reactivation stages, can be treated as that of a simple hysteretic system in which the substrate-modified enzyme is activated by a product of the reaction. It has been concluded that the early suggestions that the modification of sulphatase A was accompanied by the exposure of a second ligand-binding site are incorrect. It has been shown that, in the absence of sulphate, the rate of reversion of substrate-modified to native sulphatase A is increased by 4-nitrocatechol but not by the same concentration of 2-nitrophenol. A detailed reaction sequence is proposed. This explains the kinetic behaviour of sulphatase A with nitrocatechol sulphate or 2-nitrophenyl sulphate as substrate and in the presence or absence of sulphate.

  3. Fast transient charging at the graphene/SiO2 interface causing hysteretic device characteristics

    NASA Astrophysics Data System (ADS)

    Lee, Young Gon; Kang, Chang Goo; Jung, Uk Jin; Kim, Jin Ju; Hwang, Hyeon Jun; Chung, Hyun-Jong; Seo, Sunae; Choi, Rino; Lee, Byoung Hun

    2011-05-01

    Device instabilities of graphene metal-oxide-semiconductor field effect transistors such as hysteresis and Dirac point shifts have been attributed to charge trapping in the underlying substrate, especially in SiO2. In this letter, trapping time constants around 87 μs and 1.76 ms were identified using a short pulse current-voltage method. The values of two trapping time constants with reversible trapping behavior indicate that the hysteretic behaviors of graphene field effect transistors are due to neither charge trapping in the bulk SiO2 or tunneling into other interfacial materials. Also, it is concluded that the dc measurement method significantly underestimated the performance of graphene devices.

  4. Hysteretic Spin Crossover in Two-Dimensional (2D) Hofmann-Type Coordination Polymers.

    PubMed

    Liu, Wei; Wang, Lu; Su, Yu-Jun; Chen, Yan-Cong; Tucek, Jiri; Zboril, Radek; Ni, Zhao-Ping; Tong, Ming-Liang

    2015-09-08

    Three new two-dimensional (2D) Hofmann-type coordination polymers with general formula [Fe(3-NH2py)2M(CN)4] (3-NH2py = 3-aminopyridine, M = Ni (1), Pd (2), Pt (3)) have been synthesized. Magnetic susceptibility measurements show that they exhibited cooperative spin crossover (SCO) with remarkable hysteretic behaviors. Their hysteresis widths are 25, 37, and 30 K for 1-3, respectively. The single-crystal structure of 1 suggest that the pseudo-octahedral Fe sites are equatorially bridged by [M(CN)4](2-) to form 2D grids and axially coordinated by 3-NH2py ligands. The intermolecular interactions between layers (the offset face-to-face π···π interactions, hydrogen bonds, and weak N(amino)···Ni(II) contacts) together with the covalent bonds bridged by [M(CN)4](2-) units are responsible to the significant cooperativity.

  5. Ground state search, hysteretic behaviour, and reversal mechanism of skyrmionic textures in confined helimagnetic nanostructures

    PubMed Central

    Beg, Marijan; Carey, Rebecca; Wang, Weiwei; Cortés-Ortuño, David; Vousden, Mark; Bisotti, Marc-Antonio; Albert, Maximilian; Chernyshenko, Dmitri; Hovorka, Ondrej; Stamps, Robert L.; Fangohr, Hans

    2015-01-01

    Magnetic skyrmions have the potential to provide solutions for low-power, high-density data storage and processing. One of the major challenges in developing skyrmion-based devices is the skyrmions’ magnetic stability in confined helimagnetic nanostructures. Through a systematic study of equilibrium states, using a full three-dimensional micromagnetic model including demagnetisation effects, we demonstrate that skyrmionic textures are the lowest energy states in helimagnetic thin film nanostructures at zero external magnetic field and in absence of magnetocrystalline anisotropy. We also report the regions of metastability for non-ground state equilibrium configurations. We show that bistable skyrmionic textures undergo hysteretic behaviour between two energetically equivalent skyrmionic states with different core orientation, even in absence of both magnetocrystalline and demagnetisation-based shape anisotropies, suggesting the existence of Dzyaloshinskii-Moriya-based shape anisotropy. Finally, we show that the skyrmionic texture core reversal dynamics is facilitated by the Bloch point occurrence and propagation. PMID:26601904

  6. High fidelity point-spread function retrieval in the presence of electrostatic, hysteretic pixel response

    NASA Astrophysics Data System (ADS)

    Rasmussen, Andrew; Guyonnet, Augustin; Lage, Craig; Antilogus, Pierre; Astier, Pierre; Doherty, Peter; Gilmore, Kirk; Kotov, Ivan; Lupton, Robert; Nomerotski, Andrei; O'Connor, Paul; Stubbs, Christopher; Tyson, Anthony; Walter, Christopher

    2016-08-01

    We employ electrostatic conversion drift calculations to match CCD pixel signal covariances observed in at field exposures acquired using candidate sensor devices for the LSST Camera.1, 2 We thus constrain pixel geometry distortions present at the end of integration, based on signal images recorded. We use available data from several operational voltage parameter settings to validate our understanding. Our primary goal is to optimize flux point spread function (FPSF) estimation quantitatively, and thereby minimize sensor-induced errors which may limit performance in precision astronomy applications. We consider alternative compensation scenarios that will take maximum advantage of our understanding of this underlying mechanism in data processing pipelines currently under development. To quantitatively capture the pixel response in high-contrast/high dynamic range operational extrema, we propose herein some straightforward laboratory tests that involve altering the time order of source illumination on sensors, within individual test exposures. Hence the word hysteretic in the title of this paper.

  7. Nonlinear coda wave analysis of hysteretic elastic behavior in strongly scattering media

    NASA Astrophysics Data System (ADS)

    Ouarabi, M. Ait; Boubenider, F.; Gliozzi, A. S.; Scalerandi, M.

    2016-10-01

    Strongly scattering elastic media, such as consolidated granular materials, respond to ultrasonic pulse excitations with a long response signal with peculiar properties. The portion of the signal at late times, termed coda, is due to multiple scattering. It contains information about the elastic properties of the material, and it has been proven to be very sensitive to small variations in the modulus. Here we propose a technique based on a nonlinear analysis of the coda of a signal, which might be applied to quantify the nonlinear elastic response in consolidated granular media exhibiting a hysteretic elastic behavior. The method proposed allows for an intrinsic definition of the reference signal which is normally needed for applying coda-based methods.

  8. Hysteretic Four-Step Spin Crossover within a Three-Dimensional Porous Hofmann-like Material

    SciTech Connect

    Clements, John E.; Price, Jason R.; Neville, Suzanne M.; Kepert, Cameron J.

    2016-10-21

    Materials that display multiple stepped spin crossover (SCO) transitions with accompanying hysteresis present the opportunity for ternary, quaternary, and quinary electronic switching and data storage but are rare in existence. Herein, we present the first report of a four-step hysteretic SCO framework. Single-crystal structure analysis of a porous 3D Hofmann-like material showed long-range ordering of spin states: HS, HS0.67LS0.33, HS0.5LS0.5, HS0.33LS0.67, and LS. These detailed structural studies provide insight into how multistep SCO materials can be rationally designed through control of host–host and host–guest interactions.

  9. Hysteretic configurations in a rotating U-tube with capped ends

    NASA Astrophysics Data System (ADS)

    Weidman, P. D.

    2015-06-01

    The effect of air trapped above the liquid columns in a U-tube rotating about an axis offset from the axis of symmetry is investigated. This extends the work of Denardo, Barber, Folley and Wright (Am. J. Phys., 57, 1989) who investigated the same problem for an open-ended U-tube for which no air is trapped. They found that, owing to a combination of gravitational, centrifugal and constraint forces on the liquid, the position of the liquid-air interfaces can be hysteretic as the angular velocity is varied. The existence and strength of the hysteresis loop depends on the dimensionless offset parameter δ and the dimensionless initial liquid height γ . Associated with the hysteresis is an instability in which the liquid jumps from one equilibrium state to another, herein defined as configuration I and configuration II. With the ends of the U-tube capped, the stable liquid configurations depend on two additional parameters defined for a stationary U-tube: α , the initial ratio of trapped air to liquid volume in each U-tube column and β , the normalized pressure of air trapped above the liquid in each column. In this study β is taken at the constant value corresponding to atmospheric pressure and, based on a previous study, we adopt Boyle’s law for determining the expansion/compression of air in a rotating U-tube. A parametric study varying α shows that a critical value occurs marking the threshold between hysteretic and nonhysteretic states. A parametric study of the effect of δ is also presented.

  10. On the identification of hysteretic systems. Part I: Fitness landscapes and evolutionary identification

    NASA Astrophysics Data System (ADS)

    Worden, K.; Manson, G.

    2012-05-01

    Fairly recent work has shown that evolutionary optimisation schemes (genetic algorithms and differential evolution) offer an effective means of identifying nonlinear dynamical systems, even when the parameter estimation problem is complicated by nonlinearity in the parameters and/or the presence of unmeasured states. In particular, an evolutionary approach to the parameter estimation problem for hysteretic systems has shown promise. The current paper considers aspects of the parameter estimation problem for systems of Bouc-Wen type. In the first place, an investigation into the nature of the objective or cost function for the optimisation is made with the aim of better understanding the performance of the identification scheme. The first part of the paper also discusses the issue of setting initial estimates or ranges for the system parameters. The data on which the analysis is based are generated by computer simulation; the specific evolutionary algorithm considered is Differential Evolution (DE). Although the DE algorithm has proved to be very effective in the identification context, a minor disadvantage manifests itself in the need to set algorithm hyperparameters for the optimisation. This observation leads to the second main objective of the current paper which is to present a recently developed variant of the DE algorithm - the Self-Adaptive Differential Evolution (SADE) algorithm - which learns and adapts a subset of its own hyperparameters throughout the optimisation process. The use of the algorithm for the hysteretic system identification problem is illustrated using the simulated data and it is shown that the algorithm can provide several orders-of-magnitude improvement on the minimisation of the problem objective function.

  11. Hysteretic sediment fluxes in rainfall-driven soil erosion: Particle size effects

    NASA Astrophysics Data System (ADS)

    Cheraghi, Mohsen; Jomaa, Seifeddine; Sander, Graham C.; Barry, D. A.

    2016-11-01

    A detailed laboratory study was conducted to examine the effects of particle size on hysteretic sediment transport under time-varying rainfall. A rainfall pattern composed of seven sequential stepwise varying rainfall intensities (30, 37.5, 45, 60, 45, 37.5, and 30 mm h-1), each of 20 min duration, was applied to a 5 m × 2 m soil erosion flume. The soil in the flume was initially dried, ploughed to a depth of 20 cm and had a mechanically smoothed surface. Flow rates and sediment concentration data for seven particle size classes (<2, 2-20, 20-50, 50-100, 100-315, 315-1000, and >1000 µm) were measured in the flume effluent. Clockwise hysteresis loops in the sediment concentration versus discharge curves were measured for the total eroded soil and the finer particle sizes (<2, 2-20, and 20-50 µm). However, for particle sizes greater than 50 µm, hysteresis effects decreased and suspended concentrations tended to vary linearly with discharge. The Hairsine and Rose (HR) soil erosion model agreed well with the experimental data for the total eroded soil and for the finer particle size classes (up to 50 µm). For the larger particle size classes, the model provided reasonable qualitative agreement with the measurements although the fit was poor for the largest size class (>1000 µm). Overall, it is found that hysteresis varies amongst particle sizes and that the predictions of the HR model are consistent with hysteretic behavior of different sediment size classes.

  12. Effect of alpha-ketoglutarate and its structural analogues on hysteretic properties of alpha-ketoglutarate dehydrogenase.

    PubMed

    Bunik, V I; Romash, O G; Gomazkova, V S

    1991-01-28

    The burst of product accumulation during the KGD reaction was investigated. It has been shown not to be the obligatory feature of catalysis, but appears when increasing the enzyme saturation by KG. Structural analogues of KG and the SH-group modification suppress the initial burst without preventing catalysis. The results obtained are in favour of the existence of the regulatory site for binding KG and its structural analogues essential for hysteretic properties of KGD.

  13. Attenuation due to hysteretic damage in the free vibration of a beam

    SciTech Connect

    Mendelsohn, Daniel A.; Pecorari, Claudio

    2014-02-18

    We present an asymptotic analysis of nonlinear free vibration of a beam with a damage plane represented by nonlinear hysteretic bending and shear springs. The perturbation parameter is the product of the ratio of the nonlinear to linear parts of the stiffness times the amplitude of the free vibration. The loss of energy and ensuing attenuation due to hysteresis is accounted for by reducing the amplitude of vibration after each cycle by an amount such that the loss in total system energy equals the work done to traverse the hysteresis loop. A new Fourier representation for each cycle of the hysteresis and the deflection solution is used for this purpose and leads to higher harmonics, an evolving complex stiffness and corrected natural frequency that are linked to the attenuation. The frequency increases to its linear value from an initially reduced value. The damage parameter, frequency shift and fundamental amplitudes are presented as functions of the initial damage parameter and time (cycles of vibration). The amplitudes of several of the higher harmonics are also presented as functions of time. Many of the results exhibit sufficient sensitivity with respect to the damage parameter that they should be able to be used to characterize the damage.

  14. Effect of local buckling on hysteretic behavior of beam-column with circular cross-section

    SciTech Connect

    Ueda, Yukio; Murakawa, Hidekazu; Shaker, R.E.

    1994-12-31

    In this paper, the hysteretic behavior of beam-column member having circular cross-section under simultaneously acting constant compressive axial load and cyclic lateral load is investigated. Elasto-plastic large deformation analysis by means of Finite Element Method (FEM) is utilized in this research. An emphasis is placed on the effect of the axial compressive load and geometrical parameters on the deterioration of the ultimate strength, the stiffness and the energy-dissipation capacity. Also, effect of the tangent modulus in the strain hardening region and different hardening rules are discussed. From this study, it is found that, in the absence of the axial compressive load, no deterioration in the strength, the stiffness and the absorbed energy are observed in all investigated members having different geometries. Meanwhile, in the case of the presence of axial load, local buckling (locally accumulated deflection under cyclic loading) may be induced depending on the geometrical parameters, namely, diameter-to-thickness ratio D/t and slenderness parameter {lambda} as well as the value of axial load ratio. Such local buckling reduces the ultimate strength and the stiffness of the member. The strength and the stiffness of the member are improved with smaller values of D/t and {lambda} and larger tangent modulus in the strain hardening region of the material.

  15. Impact of Capacitive Effect and Ion Migration on the Hysteretic Behavior of Perovskite Solar Cells.

    PubMed

    Chen, Bo; Yang, Mengjin; Zheng, Xiaojia; Wu, Congcong; Li, Wenle; Yan, Yongke; Bisquert, Juan; Garcia-Belmonte, Germà; Zhu, Kai; Priya, Shashank

    2015-12-03

    In the past five years, perovskite solar cells (PSCs) based on organometal halide perovskite have exhibited extraordinary photovoltaic (PV) performance. However, the PV measurements of PSCs have been widely recognized to depend on voltage scanning condition (hysteretic current density-voltage [J-V] behavior), as well as on voltage treatment history. In this study, we find that varied PSC responses are attributable to two causes. First, capacitive effect associated with electrode polarization provides a slow transient non-steady-state photocurrent that modifies the J-V response. Second, modification of interfacial barriers induced by ion migration can modulate charge-collection efficiency so that it causes a pseudo-steady-state photocurrent, which changes according to previous voltage conditioning. Both phenomena are strongly influenced by ions accumulating at outer interfaces, but their electrical and PV effects are different. The time scale for decay of capacitive current is on the order of seconds, whereas the slow redistribution of mobile ions requires several minutes.

  16. Interactions Between Mineral Surfaces, Substrates, Enzymes, and Microbes Result in Hysteretic Temperature Sensitivities and Microbial Carbon Use Efficiencies and Weaker Predicted Carbon-Climate Feedbacks

    NASA Astrophysics Data System (ADS)

    Riley, W. J.; Tang, J.

    2014-12-01

    We hypothesize that the large observed variability in decomposition temperature sensitivity and carbon use efficiency arises from interactions between temperature, microbial biogeochemistry, and mineral surface sorptive reactions. To test this hypothesis, we developed a numerical model that integrates the Dynamic Energy Budget concept for microbial physiology, microbial trait-based community structure and competition, process-specific thermodynamically ­­based temperature sensitivity, a non-linear mineral sorption isotherm, and enzyme dynamics. We show, because mineral surfaces interact with substrates, enzymes, and microbes, both temperature sensitivity and microbial carbon use efficiency are hysteretic and highly variable. Further, by mimicking the traditional approach to interpreting soil incubation observations, we demonstrate that the conventional labile and recalcitrant substrate characterization for temperature sensitivity is flawed. In a 4 K temperature perturbation experiment, our fully dynamic model predicted more variable but weaker carbon-climate feedbacks than did the static temperature sensitivity and carbon use efficiency model when forced with yearly, daily, and hourly variable temperatures. These results imply that current earth system models likely over-estimate the response of soil carbon stocks to global warming.

  17. Hyperfine-induced hysteretic funnel structure in spin blockaded tunneling current of coupled vertical quantum dots at low magnetic field

    SciTech Connect

    Leary, A.; Wicha, A.; Harack, B.; Coish, W. A.; Hilke, M.; Yu, G.; Gupta, J. A.; Payette, C.; Austing, D. G.

    2013-12-04

    We outline the properties of the hyperfine-induced funnel structure observed in the two-electron spin blockade region of a weakly coupled vertical double quantum dot device. Hysteretic steps in the leakage current occur due to dynamic nuclear polarization when either the bias voltage or the magnetic field is swept up and down. When the bias voltage is swept, an intriguing ∼3 mT wide cusp near 0 T appears in the down-sweep position, and when the magnetic field is swept, the current at 0 T can be switched from 'low' to 'high' as the bias is increased.

  18. Ceramic problems/challenges in high temperature oxide superconductors - Hysteretic force measurements as a new analysis tool

    NASA Technical Reports Server (NTRS)

    Morgan, P. E. D.; Ratto, J. J.; Housley, R. M.; Porter, J. R.; Marshall, D. B.

    1989-01-01

    A technique is presented for analyzing high-temperature oxide superconductors using hysteretic magnetic force/distance measurements. Emphasis is placed on developing low weight, highly robust superconducting materials for space applications. Bi-Ca-Sr-Cu superconductors are prepared and characterized by standard techniques. It is found that standard techniques such as XRD, SEM, and TEM are insufficient to completely characterize superconductors. The magnetic properties of the superconductors are studied with the new technique, based on measuring the force between a magnet and the superconductor as a function of their separation.

  19. Efficiency studies of hysteretic and PWM boost converters: Controller- and battery-type effects

    NASA Astrophysics Data System (ADS)

    Sanchez, Juan Herminio, III

    A continuous conduction boost converter is studied as a function of four battery types and two controllers. The battery types are alkaline, NiCd, NiMH, and sealed lead-acid. The controllers implement voltage-mode pulse-width modulation (PWM) and hysteretic current-mode (HCM) control schemes, respectively. The boost converter is designed to produce an output of 3W at 12V DC with battery voltages ranging from 6V to 3V. The study focuses on converter efficiency as affected by battery type, controller type, and the combined effects of battery type and controller type. Computer simulations predict and experimental results verify that differences in converter efficiency between the different battery types are due to differences in capacity, current-handling capabilities, and sustained voltage levels. The HCM controller uses a control scheme, in which the switching frequency decreases as battery voltage decreases, resulting in lower MOSFET switching losses. This effect partially compensates for the increased conduction losses in converter components as more current is drawn from batteries at lower input voltages. The PWM controller has a fixed switching frequency (50 kHz) and both its switching and conduction losses increase with decreasing input voltage. Efficiency levels of 88% are achieved for higher battery voltages, decreasing to 80% for lower voltages. A difference of up to 2% higher efficiency is observed in the HCM over the PWM. The major power losses are due to the combination of the inductor's ESR and the resistance of the wire used to increase the Hall-effect current sensor turns-ratio (increasing from 400mW to 1.2W). Simulations predict that in the absence of this resistance, efficiency levels of 95% can be achieved. Conduction losses through the rectifier are in the range of 40mW to 50mW for both controllers. MOSFET switching losses amount to 50mW for both controllers at high input voltages, increasing to 100mW for the PWM, but only to 65mW for the HCM at

  20. Gaussian closure technique applied to the hysteretic Bouc model with non-zero mean white noise excitation

    NASA Astrophysics Data System (ADS)

    Waubke, Holger; Kasess, Christian H.

    2016-11-01

    Devices that emit structure-borne sound are commonly decoupled by elastic components to shield the environment from acoustical noise and vibrations. The elastic elements often have a hysteretic behavior that is typically neglected. In order to take hysteretic behavior into account, Bouc developed a differential equation for such materials, especially joints made of rubber or equipped with dampers. In this work, the Bouc model is solved by means of the Gaussian closure technique based on the Kolmogorov equation. Kolmogorov developed a method to derive probability density functions for arbitrary explicit first-order vector differential equations under white noise excitation using a partial differential equation of a multivariate conditional probability distribution. Up to now no analytical solution of the Kolmogorov equation in conjunction with the Bouc model exists. Therefore a wide range of approximate solutions, especially the statistical linearization, were developed. Using the Gaussian closure technique that is an approximation to the Kolmogorov equation assuming a multivariate Gaussian distribution an analytic solution is derived in this paper for the Bouc model. For the stationary case the two methods yield equivalent results, however, in contrast to statistical linearization the presented solution allows to calculate the transient behavior explicitly. Further, stationary case leads to an implicit set of equations that can be solved iteratively with a small number of iterations and without instabilities for specific parameter sets.

  1. On the continuum-scale simulation of gravity-driven fingers with hysteretic Richards equation: Trucation error induced numerical artifacts

    SciTech Connect

    ELIASSI,MEHDI; GLASS JR.,ROBERT J.

    2000-03-08

    The authors consider the ability of the numerical solution of Richards equation to model gravity-driven fingers. Although gravity-driven fingers can be easily simulated using a partial downwind averaging method, they find the fingers are purely artificial, generated by the combined effects of truncation error induced oscillations and capillary hysteresis. Since Richards equation can only yield a monotonic solution for standard constitutive relations and constant flux boundary conditions, it is not the valid governing equation to model gravity-driven fingers, and therefore is also suspect for unsaturated flow in initially dry, highly nonlinear, and hysteretic media where these fingers occur. However, analysis of truncation error at the wetting front for the partial downwind method suggests the required mathematical behavior of a more comprehensive and physically based modeling approach for this region of parameter space.

  2. Transport gap and hysteretic behavior of the Ising quantum Hall ferromagnets in |N |>0 Landau levels of bilayer graphene

    NASA Astrophysics Data System (ADS)

    Luo, Wenchen; Côté, R.

    2014-12-01

    The chiral two-dimensional electron gas in Landau levels |N |>0 of a Bernal-stacked graphene bilayer has a valley-pseudospin Ising quantum Hall ferromagnetic behavior at odd filling factors νN=1 ,3 of these fourfold degenerate states. At zero interlayer electrical bias, the ground state at these fillings is spin polarized and electrons occupy one valley or the other while a finite electrical bias produces a series of valley pseudospin-flip transitions. In this work, we discuss the hysteretic behavior of the Ising quantum Hall ferromagnets. We compute the transport gap due to different excitations: bulk electron-hole pairs, electron-hole pairs confined to the coherent region of a valley-pseudospin domain wall, and spin or valley-pseudospin skyrmion-antiskyrmion pairs. We determine which of these excitations has the lowest energy at a given value of the Zeeman coupling, bias, and magnetic field.

  3. Piezoelectric sensing and non-parametric statistical signal processing for health monitoring of hysteretic dampers used in seismic-resistant structures

    NASA Astrophysics Data System (ADS)

    Gallego, A.; Benavent-Climent, A.; Romo-Melo, L.

    2015-08-01

    The paper proposes a new application of non-parametric statistical processing of signals recorded from vibration tests for damage detection and evaluation on I-section steel segments. The steel segments investigated constitute the energy dissipating part of a new type of hysteretic damper that is used for passive control of buildings and civil engineering structures subjected to earthquake-type dynamic loadings. Two I-section steel segments with different levels of damage were instrumented with piezoceramic sensors and subjected to controlled white noise random vibrations. The signals recorded during the tests were processed using two non-parametric methods (the power spectral density method and the frequency response function method) that had never previously been applied to hysteretic dampers. The appropriateness of these methods for quantifying the level of damage on the I-shape steel segments is validated experimentally. Based on the results of the random vibrations, the paper proposes a new index that predicts the level of damage and the proximity of failure of the hysteretic damper.

  4. Hysteretic memory in pH-response of water contact angle on poly(acrylic acid) brushes.

    PubMed

    Yadav, Vivek; Harkin, Adrienne V; Robertson, Megan L; Conrad, Jacinta C

    2016-04-21

    We investigated the pH-dependent response of flat polyacid brushes of varying length and dispersity in the extended brush regime. Our model system consisted of poly(acrylic acid) brushes, which change from hydrophobic and neutral at low pH to hydrophilic and negatively charged at high pH, synthesized on silicon substrates using a grafting-from approach at constant grafting density. We observed three trends in the pH-response: first, the dry brush thickness increased as the pH was increased for brushes above a critical length, and this effect was magnified as the dispersity increased; second, the water contact angle measured at low pH was larger for brushes of greater dispersity; and third, brushes of sufficient dispersity exhibited hysteretic memory behavior in the pH-dependence of the contact angle, in which the contact angle upon increasing and decreasing pH differed. As a consequence, the pKa of the brushes measured upon increasing pH was consistently higher than that measured upon decreasing pH. The observed pH response is consistent with proposed changes in the conformation and charge distribution of the polyelectrolyte brushes that depend on the direction of pH change and the dispersity of the brushes.

  5. Investigation of Deterioration Behavior of Hysteretic Loops in Nonlinear Static Procedure Analysis of Concrete Structures with Shear Walls

    SciTech Connect

    Ghodrati Amiri, G.; Amidi, S.; Khorasani, M.

    2008-07-08

    In the recent years, scientists developed the seismic rehabilitation of structures and their view points were changed from sufficient strength to the performance of structures (Performance Base Design) to prepare a safe design. Nonlinear Static Procedure analysis (NSP) or pushover analysis is a new method that is chosen for its speed and simplicity in calculations. 'Seismic Rehabilitation Code for Existing Buildings' and FEMA 356 considered this method. Result of this analysis is a target displacement that is the base of the performance and rehabilitation procedure of the structures. Exact recognition of that displacement could develop the workability of pushover analysis. In these days, Nonlinear Dynamic Analysis (NDP) is only method can exactly apply the seismic ground motions. In this case because it consumes time, costs very high and is more difficult than other methods, is not applicable as much as NSP. A coefficient used in NSP for determining the target displacement is C2 (Stiffness and Strength Degradations Coefficient) and is applicable for correcting the errors due to eliminating the stiffness and strength degradations in hysteretic loops. In this study it has been tried to analysis three concrete frames with shear walls by several accelerations that scaled according to FEMA 273 and FEMA 356. These structures were designed with Iranian 2800 standard (vers.3). Finally after the analyzing by pushover method and comparison results with dynamic analysis, calculated C2 was comprised with values in rehabilitation codes.

  6. A 2D spring model for the simulation of ultrasonic wave propagation in nonlinear hysteretic media.

    PubMed

    Delsanto, P P; Gliozzi, A S; Hirsekorn, M; Nobili, M

    2006-07-01

    A two-dimensional (2D) approach to the simulation of ultrasonic wave propagation in nonclassical nonlinear (NCNL) media is presented. The approach represents the extension to 2D of a previously proposed one dimensional (1D) Spring Model, with the inclusion of a PM space treatment of the intersticial regions between grains. The extension to 2D is of great practical relevance for its potential applications in the field of quantitative nondestructive evaluation and material characterization, but it is also useful, from a theoretical point of view, to gain a better insight of the interaction mechanisms involved. The model is tested by means of virtual 2D experiments. The expected NCNL behaviors are qualitatively well reproduced.

  7. Hysteretic and intermittent regimes in the subcritical bifurcation of a quasi-one-dimensional system of interacting particles

    NASA Astrophysics Data System (ADS)

    Dessup, Tommy; Coste, Christophe; Saint Jean, Michel

    2016-01-01

    In this article, we study the effects of white Gaussian additive thermal noise on a subcritical pitchfork bifurcation. We consider a quasi-one-dimensional system of particles that are transversally confined, with short-range (non-Coulombic) interactions and periodic boundary conditions in the longitudinal direction. In such systems, there is a structural transition from a linear order to a staggered row, called the zigzag transition. There is a finite range of transverse confinement stiffnesses for which the stable configuration at zero temperature is a localized zigzag pattern surrounded by aligned particles, which evidences the subcriticality of the bifurcation. We show that these configurations remain stable for a wide temperature range. At zero temperature, the transition between a straight line and such localized zigzag patterns is hysteretic. We have studied the influence of thermal noise on the hysteresis loop. Its description is more difficult than at T =0 K since thermally activated jumps between the two configurations always occur and the system cannot stay forever in a unique metastable state. Two different regimes have to be considered according to the temperature value with respect to a critical temperature Tc(τobs) that depends on the observation time τobs. An hysteresis loop is still observed at low temperature, with a width that decreases as the temperature increases toward Tc(τobs) . In contrast, for T >Tc(τobs) the memory of the initial condition is lost by stochastic jumps between the configurations. The study of the mean residence times in each configuration gives a unique opportunity to precisely determine the barrier height that separates the two configurations, without knowing the complete energy landscape of this many-body system. We also show how to reconstruct the hysteresis loop that would exist at T =0 K from high-temperature simulations.

  8. The hysteretic contribution of friction for the polished rubber on the concrete surface

    NASA Astrophysics Data System (ADS)

    Feshanjerdi, M.; Khorrami, M.; Masoudi, A. A.; Razzaghi Kashani, M.

    2017-02-01

    The rubber friction coefficient, and the contact area during stationary sliding is calculated, for the contact of a polished rubber block and a concrete surface, when both surfaces are rough. The calculation is based on an extended version of Persson's contact mechanics theory. Compared to only the substrate being rough, when both of the surfaces are rough but their cross correlation is zero, the friction coefficient is larger. Introducing a positive correlation decreases the friction coefficient, while introducing a negative correlation increases the friction coefficient. To support these theoretical arguments, some experiments have been performed. We have produced roughness on the rubber surface, using abrasive paper, and measured the surface topographies for the concrete and the polished rubber surfaces. The auto spectral density functions for the both surfaces have been calculated, and the rubber viscoelastic modulus mastercurve has been obtained. We have measured the rubber friction at different sliding velocities, when the rubber surfaces are rough and smooth, and compared it to the theoretical results. It is seen that when the rubber surface is rough, the rubber friction coefficient is larger compared to the case the rubber surface is smooth. The theoretical results are in good agreement with experimental observation.

  9. Selective All-Wet Metallization of Silicon for Hysteretic Power Microswitches

    NASA Astrophysics Data System (ADS)

    Uncuer, Muhammet

    electroless Au-to-Au contact from the source to the drain has been characterized. It has been found that the current-voltage (Ids-Vds) curves show ohmic characteristics with modest contact resistance of 5 kΩ. Moreover, the fabricated devices display over-damped behavior with a switching time of around 80 µs and squeeze-film damping of 0.0023 N-s/m². Lifetime/reliability experiments have shown promising results (exceeding 2000 stable hot cycling with a current load of 1 mA); however more improvement is necessary for an eventual marketable product. What is more, intentional stress-imbalance is induced on the fabricated micro-structures to determine thin-film stresses for the electroless Cu (tensile stress of 45 MPa for 100 nm thick film) and Au/Cu (tensile stress of 56 MPa for 100 nm thick film) for the material characterization purposes.

  10. On the identification of Hammerstein systems in the presence of an input hysteretic nonlinearity with nonlocal memory: Piezoelectric actuators - an experimental case study

    NASA Astrophysics Data System (ADS)

    Butcher, Mark; Giustiniani, Alessandro; Masi, Alessandro

    2016-04-01

    The identification problem of the linear dynamic part of piezo based actuators is addressed in this paper, exploiting the use of binary signals, specifically the pseudo random binary sequences (PRBS). Due to the presence of nonlocal memory hysteretic behavior in piezoelectric active materials, the dependence of the identification results on this strongly nonlinear effect is analyzed and useful guidelines for the design of the PRBS stimulating signal are derived. Moreover, some properties of hysteresis like cancellation and congruency are experimentally analyzed and their effects on the identification process are discussed. Finally, the use of a hysteresis compensation strategy in the identification process is evaluated and discussed.

  11. Tl 2Ba 2CaCu 2O 8- x superconducting films deposited by aerosol and their hysteretic ac losses

    NASA Astrophysics Data System (ADS)

    Conde-Gallardo, A.; Klein, T.; Escribe-Filippini, C.; Marcus, J.; Lopez-Rios, T.; Jergel, M.

    1998-04-01

    ac susceptibility measurements have been performed on Tl 2Ba 2CaCu 2O 8- x superconducting films. The films were grown in two steps: first Ba-Ca-Cu-Ag-O precursor films have been prepared by spraying an aerosol on MgO substrates and the Tl was then subsequently introduced by diffusion into the precursor films. The most favourable preparation conditions have been determined by comparing the structural and magnetic properties of the films. A detailed study of the ac susceptibility shows that the ac losses are due to intragrain bulk hysteretic pinning eventhough small geometrical barriers contributions could also be observed.

  12. Collisions, Cannibals, and the Memory of Long-lost Bed Forms: The Hyster(et)ical Story Revealed

    NASA Astrophysics Data System (ADS)

    Jerolmack, D. J.; Martin, R. L.

    2015-12-01

    Sandy river-bed morphology often lags changes in water discharge, producing hysteresis in the relation between discharge and bed-form geometry. While this effect is well known, its origins are not. In this talk we present experimental and field results that reveal these origins. We show that the primary mechanism of bed form growth in a rising flood is merger induced by collisions, which occur due to a dispersion in migration rates. At the start of a flood the bed forms are small and transport rate is high, so growth is rapid. Conversely, on the falling limb of a flood the bed forms are large while the transport rate is small. If the flood recedes rapidly enough, the large bed forms cease migrating and small, secondary bed forms emerge on their backs. These smaller features cannibalize the original, relict structures which slowly diffuse away. (We do not distinguish between ripples and dunes, the data do not indicate any reason to do so, and we therefore recuse ourselves from discussing that tiring topic.). The timescale of decay is much larger than growth, leaving a memory of peak-flood conditions that may persist until the next flood. Thus, the timescales of both growth (Tg) and decay (Td) are related to a simple bed form turnover time - the time to displace a bed form's volume by transport - however, the turnover time is different for growth vs. decay. This reveals three different regimes for the response of bed forms to a flood: (1) a slow flood with a timescale Tf > Td > Tg is quasi-steady, i.e., bed forms grow and shrink with no lag between morphology and flow; (2) an intermediate flood with Td > Tf > Tg exhibits quasi-steady growth, but decay lags the flow; and (3) a fast flood with Td > Tg > Tf produces a lag between morphology and flow over the entire hydrograph. Regimes 2 and 3 produce hysteretical behavior, with 3 being the most extreme. We discuss the implications of these results for: predicting stage-discharge relations, anticipating and understanding

  13. Hysteretic Faraday waves

    NASA Astrophysics Data System (ADS)

    Périnet, Nicolas; Falcón, Claudio; Chergui, Jalel; Shin, Seungwon; Juric, Damir

    2016-11-01

    We study with numerical simulations the two-dimensional Faraday waves in two immiscible incompressible fluids when the lower fluid layer is shallow. After the appearance of the well known subharmonic stationary waves, a further instability is observed while the control parameter passes a secondary threshold. A new state then arises, composed of stationary waves with about twice the original pattern amplitude. The bifurcation presents hysteresis: there exists a finite range of the control parameter in which both states are stable. By means of a simple stress balance, we show that a change of the shear stress can explain this hysteresis. Our predictions based on this model are in agreement with our numerical results. Project funded by FONDECYT Grants 1130354, 3140522 and the National Research Foundation of Korea (NRF- 2014R1A2A1A11051346). Computations supported by the supercomputing infrastructures of the NLHPC (ECM-02) and GENCI (IDRIS).

  14. Hysteretic Faraday waves.

    PubMed

    Périnet, Nicolas; Falcón, Claudio; Chergui, Jalel; Juric, Damir; Shin, Seungwon

    2016-06-01

    We report on the numerical and theoretical study of the subcritical bifurcation of parametrically amplified waves appearing at the interface between two immiscible incompressible fluids when the layer of the lower fluid is very shallow. As a critical control parameter is surpassed, small amplitude surface waves bifurcate subcritically toward highly nonlinear ones with twice their amplitude. We relate this hysteresis with the change of shear stress using a simple stress balance, in agreement with numerical results.

  15. Electrooptical Analysis of Microbial Cell Suspensions forDetermination of Antibiotic Resistance.

    PubMed

    Guliy, Olga I; Bunin, Victor D; Korzhenevich, Vyacheslav I; Volkov, Alexey A; Ignatov, Oleg V

    2016-12-01

    The effects of ampicillin; kanamycin, chloramphenicol, and tetracycline on electrophysical characteristics of cells of sensitive (ampicillin; kanamycin, chloramphenicol) and resistant (ampicillin; kanamycin, chloramphenicol, tetracycline) Escherichia coli strains were studied. Under the action of antibiotics sensitive and resistant E. coli strains acquire different electro-optical properties. Changes in suspension-orientational spectra, that are observed under the action of ampicillin; kanamycin, chloramphenicol, and tetracycline can be used in determination of antibiotic resistance of the studied bacterial strains. In our opinion, the methods of microbial suspension electro-optical analysis can be used in microbiology, mеdicinе, veterinary, and are an effective tool for solving the problems connected with determination of microbial cell antibiotic resistance.

  16. Robust solution procedure for the discrete energy-averaged model on the calculation of 3D hysteretic magnetization and magnetostriction of iron-gallium alloys

    NASA Astrophysics Data System (ADS)

    Tari, H.; Scheidler, J. J.; Dapino, M. J.

    2015-06-01

    A reformulation of the Discrete Energy-Averaged model for the calculation of 3D hysteretic magnetization and magnetostriction of iron-gallium (Galfenol) alloys is presented in this paper. An analytical solution procedure based on an eigenvalue decomposition is developed. This procedure avoids the singularities present in the existing approximate solution by offering multiple local minimum energy directions for each easy crystallographic direction. This improved robustness is crucial for use in finite element codes. Analytical simplifications of the 3D model to 2D and 1D applications are also presented. In particular, the 1D model requires calculation for only one easy direction, while all six easy directions must be considered for general applications. Compared to the approximate solution procedure, it is shown that the resulting robustness comes at no expense for 1D applications, but requires almost twice the computational effort for 3D applications. To find model parameters, we employ the average of the hysteretic data, rather than anhysteretic curves, which would require additional measurements. An efficient optimization routine is developed that retains the dimensionality of the prior art. The routine decouples the parameters into exclusive sets, some of which are found directly through a fast preprocessing step to improve accuracy and computational efficiency. The effectiveness of the model is verified by comparison with existing measurement data.

  17. Metastability and hysteretic vortex pinning near the order-disorder transition in NbSe2: Interplay between plastic and elastic energy barriers

    NASA Astrophysics Data System (ADS)

    Marziali Bermúdez, M.; Louden, E. R.; Eskildsen, M. R.; Dewhurst, C. D.; Bekeris, V.; Pasquini, G.

    2017-03-01

    We studied thermal and dynamic history effects in the vortex lattice (VL) near the order-disorder transition in clean NbSe2 single crystals. Comparing the evolution of the effective vortex pinning and the bulk VL structure, we observed metastable superheated and supercooled VL configurations that coexist with a hysteretic effective pinning response due to thermal cycling of the system. A novel scenario, governed by the interplay between (lower) elastic and (higher) plastic energy barriers, is proposed as an explanation for our observations: Plastic barriers, which prevent the annihilation or creation of topological defects, require dynamic assistance to be overcome and to achieve a stable VL at each temperature. Conversely, thermal hysteresis in the pining response is ascribed to low energy barriers, which inhibit rearrangement within a single VL correlation volume and are easily overcome as the relative strength of competing interactions changes with temperature.

  18. Hysteretic characteristics of 1/λ⁴ scattering of light during adsorption and desorption of water in porous Vycor glass with nanopores.

    PubMed

    Ogawa, Shigeo; Nakamura, Jiro

    2013-10-01

    Porous Vycor glass with nanopores is transparent in the visible region and is often used in colorimetric chemical sensing when impregnated with selectively reacting reagents. However, it has some disadvantages in sensing, since changes in the humidity of ambient air strongly affect its transmission. In this work, by combining a humidity-controlled thermostatic chamber and an ultraviolet-visible and near-infrared spectrophotometer through fiber optics, we analyzed the effect of increasing and decreasing humidity in the ambient air on the transparency change of the nanoporous glass. The transparency response in the visible region to changes in humidity is analyzed to correlate the turbidity response of the glass with the amount of water in it. The turbidity is found to be dependent on the inverse fourth power of the wavelength (1/λ⁴), which implies that Rayleigh-type scattering takes place for both adsorption and desorption of water. We show that measures of the extent of the optical inhomogeneity that causes the scattering, such as the effective radius of scatterers and their number density, exhibit a pronounced hysteretic characteristic for the imbibition and drainage of water, while the absorption inherent to imbibed water also shows another type of hysteresis that is quite similar to the sorption isotherms of water. On the basis of the above observations, we show that the transitory white turbidity of nanoporous glasses during changes in humidity can be consistently interpreted and quantitatively analyzed by a simple Rayleigh scattering mechanism.

  19. The relationship between the transition voltage of the I- V curve of the ferroelectrics and the coercive field of the P- V hysteretic curve

    NASA Astrophysics Data System (ADS)

    Xingjiao, Li; Junbo, Bao; Ningzhang, Wang; Jingping, Xu; Tao, Chen; Xuecheng, Zou; Hanhua, Feng; Shaoping, Li

    2002-07-01

    The relationship between the transition voltage of the I- V curve of the ferroelectrics and the coercive field of the P- V hysteretic curve is calculated. The first mathematical analysis to explain the relation between the transition voltage Vt and the coercive voltage Vc is obtained. The origin of the interrelation between the transition voltage of the I- V curve and the coercive field is that the height of the boundary barrier is inversely proportional to the effective dielectric constant of the near-boundary region, which is dependent on a derivative of polarization on the electric field, ∂P/ ∂E. The term ξ( eVt) plus the term ( enb2δ/ dNdPs)( eVc) equals a constant. Vt is the function of Eg, Ps, Vc, and E. There is a linear relation between Vc and Vt. This relationship will induce the matchable relations between the I- V curve and the E- P loop. As long as the Vc of the V- P loop exists, the correspondent Vt of I- V curve will certainly exist. It will be the foundation of a new ferroelectric memory, which operates by the I- V characteristics. These relations are the conditions that can enable nonvolatile memory and nondestructive readout.

  20. Positive exchange-bias and giant vertical hysteretic shift in La0.3Sr0.7FeO3/SrRuO3 bilayers

    PubMed Central

    Rana, Rakesh; Pandey, Parul; Singh, R. P.; Rana, D. S.

    2014-01-01

    The exchange-bias effects in the mosaic epitaxial bilayers of the itinerant ferromagnet (FM) SrRuO3 and the antiferromagnetic (AFM) charge-ordered La0.3Sr0.7FeO3 were investigated. An uncharacteristic low-field positive exchange bias, a cooling-field driven reversal of positive to negative exchange-bias and a layer thickness optimised unusual vertical magnetization shift were all novel facets of exchange bias realized for the first time in magnetic oxides. The successive magnetic training induces a transition from positive to negative exchange bias regime with changes in domain configurations. These observations are well corroborated by the hysteretic loop asymmetries which display the modifications in the AFM spin correlations. These exotic features emphasize the key role of i) mosaic disorder induced subtle interplay of competing AFM-superexchange and FM double exchange at the exchange biased interface and, ii) training induced irrecoverable alterations in the AFM spin structure. PMID:24569516

  1. Dynamic phase transition properties and hysteretic behavior of a ferrimagnetic core-shell nanoparticle in the presence of a time dependent magnetic field

    NASA Astrophysics Data System (ADS)

    Yüksel, Yusuf; Vatansever, Erol; Polat, Hamza

    2012-10-01

    We have presented dynamic phase transition features and stationary-state behavior of a ferrimagnetic small nanoparticle system with a core-shell structure. By means of detailed Monte Carlo simulations, a complete picture of the phase diagrams and magnetization profiles has been presented and the conditions for the occurrence of a compensation point Tcomp in the system have been investigated. According to Néel nomenclature, the magnetization curves of the particle have been found to obey P-type, N-type and Q-type classification schemes under certain conditions. Much effort has been devoted to investigating the hysteretic response of the particle, and we observed the existence of triple hysteresis loop behavior, which originates from the existence of a weak ferromagnetic core coupling Jc/Jsh, as well as a strong antiferromagnetic interface exchange interaction Jint/Jsh. Most of the calculations have been performed for a particle in the presence of oscillating fields of very high frequencies and high amplitudes in comparison with exchange interactions, which resembles a magnetic system under the influence of ultrafast switching fields. Particular attention has also been paid to the influence of the particle size on the thermal and magnetic properties, as well as magnetic features such as coercivity, remanence and the compensation temperature of the particle. We have found that, in the presence of ultrafast switching fields, the particle may exhibit a dynamic phase transition from paramagnetic to a dynamically ordered phase with increasing ferromagnetic shell thickness.

  2. Hysteretic photochromic switching of Eu-Mg defects in GaN links the shallow transient and deep ground states of the Mg acceptor

    PubMed Central

    Singh, A. K.; O’Donnell, K. P.; Edwards, P. R.; Lorenz, K.; Kappers, M. J.; Boćkowski, M.

    2017-01-01

    Although p-type activation of GaN by Mg underpins a mature commercial technology, the nature of the Mg acceptor in GaN is still controversial. Here, we use implanted Eu as a ‘spectator ion’ to probe the lattice location of Mg in doubly doped GaN(Mg):Eu. Photoluminescence spectroscopy of this material exemplifies hysteretic photochromic switching (HPS) between two configurations, Eu0 and Eu1(Mg), of the same Eu-Mg defect, with a hyperbolic time dependence on ‘switchdown’ from Eu0 to Eu1(Mg). The sample temperature and the incident light intensity at 355 nm tune the characteristic switching time over several orders of magnitude, from less than a second at 12.5 K, ~100 mW/cm2 to (an estimated) several hours at 50 K, 1 mW/cm2. Linking the distinct Eu-Mg defect configurations with the shallow transient and deep ground states of the Mg acceptor in the Lany-Zunger model, we determine the energy barrier between the states to be 27.7(4) meV, in good agreement with the predictions of theory. The experimental results further suggest that at low temperatures holes in deep ground states are localized on N atoms axially bonded to Mg acceptors. PMID:28155896

  3. Temperature-dependent transport and hysteretic behaviors induced by interfacial states in MoS2 field-effect transistors with lead-zirconate-titanate ferroelectric gating

    NASA Astrophysics Data System (ADS)

    Sun, Yilin; Xie, Dan; Zhang, Xiaowen; Xu, Jianlong; Li, Xinming; Li, Xian; Dai, Ruixuan; Li, Xiao; Li, Peilian; Gao, Xingsen; Zhu, Hongwei

    2017-01-01

    We report the temperature and gate-voltage-dependent electrical properties of lead-zirconate-titanate-gated MoS2 field-effect transistors (MoS2-PZT FETs) within a temperature range of 300 to 380 K. The MoS2 transistors with PZT gating exhibit large reproducible clockwise hysteresis, which is induced by the dynamic charge-trapping/de-trapping process of interfacial states between PZT films and MoS2 channels under the modulation of ferroelectric polarization of PZT films. In this way, the modulation of the gate effect on the hysteresis behavior has been achieved by activating the dynamic charge-trapping/de-trapping process in the interfacial states under different V gs . Moreover, the temperature dependence of the current in the range of 300 to 380 K indicates thermally activated hysteretic behaviors. The hysteresis in the transfer characteristics of MoS2-PZT FETs shows a simultaneous enlargement with increasing temperature, which can be attributed to the thermally sensitive dynamic trapping/de-trapping process of interfacial states.

  4. Hysteretic behavior of Fe(phen){sub 2}(NCS){sub 2} spin-transition microparticles vs. the environment: A huge reversible component resolved by first order reversal curves

    SciTech Connect

    Tanasa, Radu; Stancu, Alexandru; Enachescu, Cristian; Laisney, Jérôme; Boillot, Marie-Laure

    2014-01-20

    We discuss the influence of the embedding matrix on the thermal hysteretic behavior of spin transition microparticles of Fe(phen){sub 2}(NCS){sub 2} by using a series of experimental first order reversal curves (FORCs). The shape of FORCs supports the hypothesis considering additional interactions between the spin-transition microparticles and the embedding matrix, which compares to a negative pressure on the particles. A mean-field approach based on negative variable external pressures, together with a cut off/switch on of particles-matrix interactions accounts for the experimental features.

  5. 2169 steel waveform experiments.

    SciTech Connect

    Furnish, Michael David; Alexander, C. Scott; Reinhart, William Dodd; Brown, Justin L.

    2012-11-01

    In support of LLNL efforts to develop multiscale models of a variety of materials, we have performed a set of eight gas gun impact experiments on 2169 steel (21% Cr, 6% Ni, 9% Mn, balance predominantly Fe). These experiments provided carefully controlled shock, reshock and release velocimetry data, with initial shock stresses ranging from 10 to 50 GPa (particle velocities from 0.25 to 1.05 km/s). Both windowed and free-surface measurements were included in this experiment set to increase the utility of the data set, as were samples ranging in thickness from 1 to 5 mm. Target physical phenomena included the elastic/plastic transition (Hugoniot elastic limit), the Hugoniot, any phase transition phenomena, and the release path (windowed and free-surface). The Hugoniot was found to be nearly linear, with no indications of the Fe phase transition. Releases were non-hysteretic, and relatively consistent between 3- and 5-mmthick samples (the 3 mm samples giving slightly lower wavespeeds on release). Reshock tests with explosively welded impactors produced clean results; those with glue bonds showed transient releases prior to the arrival of the reshock, reducing their usefulness for deriving strength information. The free-surface samples, which were steps on a single piece of steel, showed lower wavespeeds for thin (1 mm) samples than for thicker (2 or 4 mm) samples. A configuration used for the last three shots allows release information to be determined from these free surface samples. The sample strength appears to increase with stress from ~1 GPa to ~ 3 GPa over this range, consistent with other recent work but about 40% above the Steinberg model.

  6. Intra-molecular interactions dominating the dehydration of a poly(2-isopropyl-2-oxazoline)-based densely grafted polymer comb in aqueous solution and hysteretic liquid-liquid phase separation.

    PubMed

    Zhou, Yuanyuan; Tang, Hui; Wu, Peiyi

    2017-03-01

    Temperature-induced phase transition together with the liquid-liquid phase separation (LLPS) phenomenon of poly(oligo(2-isopropyl-2-oxazoline)methacrylate) with the comb-shaped architecture (comb-PiPOx) in aqueous solution has been discussed at the molecular level. Differing from linear poly(2-isopropyl-2-oxazoline) (linear-PiPOx), polymer-rich liquid droplets appear at higher temperature compared with the phase transition determined by differential scanning calorimetry (DSC) in comb-PiPOx solution. As investigated using variable-temperature Fourier transform infrared (FTIR) spectra analysis, the densely grafted architecture gives rise to an intra-molecular interaction (hydrophobic interaction of alkyl groups and H-bond of carbonyl groups) dominating the dehydration process of comb-PiPOx. With temperature increment, most of the water within hydrated polymers is expelled to the outer water phase through intra-molecular association, corresponding to the transition temperature. Afterwards, the dehydration of methyl groups on side chain ends reflects the massive aggregation of polymer chains through inter-molecular association, accompanied by hysteretic LLPS.

  7. The uncoupled ATPase activity of the ABC transporter BtuC2D2 leads to a hysteretic conformational change, conformational memory, and improved activity

    PubMed Central

    Livnat-Levanon, Nurit; I. Gilson, Amy; Ben-Tal, Nir; Lewinson, Oded

    2016-01-01

    ABC transporters comprise a large and ubiquitous family of proteins. From bacteria to man they translocate solutes at the expense of ATP hydrolysis. Unlike other enzymes that use ATP as an energy source, ABC transporters are notorious for having high levels of basal ATPase activity: they hydrolyze ATP also in the absence of their substrate. It is unknown what are the effects of such prolonged and constant activity on the stability and function of ABC transporters or any other enzyme. Here we report that prolonged ATP hydrolysis is beneficial to the ABC transporter BtuC2D2. Using ATPase assays, surface plasmon resonance interaction experiments, and transport assays we observe that the constantly active transporter remains stable and functional for much longer than the idle one. Remarkably, during extended activity the transporter undergoes a slow conformational change (hysteresis) and gradually attains a hyperactive state in which it is more active than it was to begin with. This phenomenon is different from stabilization of enzymes by ligand binding: the hyperactive state is only reached through ATP hydrolysis, and not ATP binding. BtuC2D2 displays a strong conformational memory for this excited state, and takes hours to return to its basal state after catalysis terminates. PMID:26905293

  8. Identification of Damage in Hysteretic Structures.

    DTIC Science & Technology

    1983-07-01

    APPROXIMATELY ITS ERROR. C 1 DX=-O.5*DA FV(2 )=QF(ALPHA.O. 5*DX) FV(4)=QF(ALPHA+1. 5*DX) KOUNT=KOUNT.2 WT=DX/6.0 ESTL-W*(FV(1)e4.O*FV(2)+FV(3)) ESTR =-WT*(FV(3...44.0*FV(4)+FV(5)) SUM=ESTL+ ESTR ARESTL-W*(ABS(FV(1) )+ABS(4.O*FV(2) )+ABS(FV(3))) ARESTRT-*(ABS(FV(3))+ABS(4.0*1(4))+ABS(FV(S))) ARE--AEA+(ARESTL+ARESTR...LORR( LVL)0O F1T(LVL)=FV(3) F2T(LVL)=FV(4) F3T(LVL)=FV(5) DA=DX DAT(LVL)=DX AREST-ARESTL ARE STT (LVL )=ARESTR EST=ESTL ESTT(LVL)= ESTR EPS=EPS/1 .4

  9. Two-dimensional vertical moisture-pressure dynamics above groundwater waves: Sand flume experiments and modelling

    NASA Astrophysics Data System (ADS)

    Shoushtari, Seyed Mohammad Hossein Jazayeri; Cartwright, Nick; Perrochet, Pierre; Nielsen, Peter

    2017-01-01

    This paper presents a new laboratory dataset on the moisture-pressure relationship above a dispersive groundwater wave in a two-dimensional vertical unconfined sand flume aquifer driven by simple harmonic forcing. A total of five experiments were conducted in which all experimental parameters were kept constant except for the oscillation period, which ranged from 268 s to 2449 s between tests. Moisture content and suction head sensor pairings were co-located at two locations in the unsaturated zone both approximately 0.2 m above the mean watertable elevation and respectively 0.3 m and 0.75 m from the driving head boundary. For all oscillation periods except for the shortest (T = 268s), the formation of a hysteretic moisture-pressure scanning loop was observed. Consistent with the decay of the saturated zone groundwater wave, the size of the observed moisture-pressure scanning loops decayed with increasing distance landward and the decay rate is larger for the shorter oscillation periods. At the shortest period (T = 268s), the observed moisture-pressure relationship was observed to be non-hysteretic but with a capillary capacity that differs from that of the static equilibrium wetting and drying curves. This finding is consistent with observations from existing one-dimensional vertical sand column experiments. The relative damping of the moisture content with distance landward is higher than that for the suction head consistent with the fact that transmission of pressure through a porous medium occurs more readily than mass transfer. This is further supported by the fact that observed phase lags for the unsaturated zone variables (i.e. suction head and moisture content) relative to the driving head are greater than the saturated zone variables (i.e. piezometric head). Harmonic analysis of the data reveals no observable generation of higher harmonics in either moisture or pressure despite the strongly non-linear relationship between the two. In addition, a phase lag

  10. Nonlinear Ultrasound Propagation in Solid ^4{He} Compared with Shear Modulus Experiments

    NASA Astrophysics Data System (ADS)

    Iwasa, Izumi; Kojima, Harry

    2016-10-01

    Ultrasound attenuation (α ) and velocity (V) at 9.6 MHz are measured in polycrystalline hcp ^4{He} . The ultrasound signal above 200 mK is linear and understood in terms of resonant vibration of dislocation segments pinned between network nodes with an average pinning length of 3.7 μ m, much shorter than 59 μ m estimated from a shear modulus measurement. Dramatic changes in α and V are observed below 200 mK. The changes are strongly dependent on temperature and are nonlinear and hysteretic. These effects result from pinning of dislocations by ^3{He} impurities (nominal concentration of 0.3 ppm). The dislocation damping constant due to thermal phonons, the binding energy between dislocation and ^3{He} , and the average network pinning length obtained from the ultrasound data are compared with those from the shear modulus experiments.

  11. Psychology Experiments.

    ERIC Educational Resources Information Center

    McGraw, Ken; Tew, Mark D.; Williams, John E.

    2001-01-01

    A goal of the PsychExperiments project was to reduce the financial burden on psychology departments for hardware/software used in their laboratories. In its third year, the PsychExperiments site now hosts 39 experiments. Over 200 classrooms worldwide have signed up as official site users and there have been nearly 10,000 data sessions conducted.…

  12. Simulated Experiments

    ERIC Educational Resources Information Center

    Snadden, R. B.; Runquist, O.

    1975-01-01

    Presents an experiment in which a programmable calculator is employed as a data generating system for simulated laboratory experiments. The example used as an illustration is a simulated conductimetric titration of an aqueous solution of HC1 with an aqueous solution of NaOH. (Author/EB)

  13. TRIO experiment

    SciTech Connect

    Clemmer, R.G.; Finn, P.A.; Malecha, R.F.; Misra, B.; Billone, M.C.; Bowers, D.L.; Fischer, A.K.; Greenwood, L.R.; Mattas, R.F.; Tam, S.W.

    1984-09-01

    The TRIO experiment is a test of in-situ tritium recovery and heat transfer performance of a miniaturized solid breeder blanket assembly. The assembly (capsule) was monitored for temperature and neutron flux profiles during irradiation and a sweep gas flowed through the capsule to an anaytical train wherein the amounts of tritium in its various chemical forms were determined. The capsule was designed to operate at different temperatures and sweep gas conditions. At the end of the experiment the amount of tritium retained in the solid was at a concentration of less than 0.1 wppM. More than 99.9% of tritium generated during the experiment was successfully recovered. The results of the experiment showed that the tritium inventories at the beginning and at the end of the experiment follow a relationship which appears to be characteristic of intragranular diffusion.

  14. Mixture Experiments

    SciTech Connect

    Piepel, Gregory F.

    2007-12-01

    A mixture experiment involves combining two or more components in various proportions or amounts and then measuring one or more responses for the resulting end products. Other factors that affect the response(s), such as process variables and/or the total amount of the mixture, may also be studied in the experiment. A mixture experiment design specifies the combinations of mixture components and other experimental factors (if any) to be studied and the response variable(s) to be measured. Mixture experiment data analyses are then used to achieve the desired goals, which may include (i) understanding the effects of components and other factors on the response(s), (ii) identifying components and other factors with significant and nonsignificant effects on the response(s), (iii) developing models for predicting the response(s) as functions of the mixture components and any other factors, and (iv) developing end-products with desired values and uncertainties of the response(s). Given a mixture experiment problem, a practitioner must consider the possible approaches for designing the experiment and analyzing the data, and then select the approach best suited to the problem. Eight possible approaches include 1) component proportions, 2) mathematically independent variables, 3) slack variable, 4) mixture amount, 5) component amounts, 6) mixture process variable, 7) mixture of mixtures, and 8) multi-factor mixture. The article provides an overview of the mixture experiment designs, models, and data analyses for these approaches.

  15. Hydronuclear experiments

    SciTech Connect

    Thorn, R.N.; Westervelt, D.R.

    1987-02-01

    Hydronuclear experiments, a method for assessing some aspects of nuclear weapon safety, were conducted at Los Alamos during the 1958 to 1961 moratorium on nuclear testing. The experiments resulted in subcritical multiplying assemblies or a very slight degree of supercriticality and, in some cases, involved a slight, but insignificant, fission energy release. These experiments helped to identify so-called one-point safety problems associated with some of the nuclear weapons systems of that time. The need for remedial action was demonstrated, although some of the necessary design changes could not be made until after the resumption of weapons testing at the end of 1961.

  16. Interpretive Experiments

    ERIC Educational Resources Information Center

    DeHaan, Frank, Ed.

    1977-01-01

    Describes an interpretative experiment involving the application of symmetry and temperature-dependent proton and fluorine nmr spectroscopy to the solution of structural and kinetic problems in coordination chemistry. (MLH)

  17. Wanted: Experiments

    ERIC Educational Resources Information Center

    McDaniel, Floyd D.

    1974-01-01

    Describes a project to produce a series of laboratory manuals and instructional materials in which nuclear experiments are presented for the undergraduate advanced laboratory. The manuals are being compiled in the areas of physics, chemistry, geology and environmental sciences. (BR)

  18. Experiment Databases

    NASA Astrophysics Data System (ADS)

    Vanschoren, Joaquin; Blockeel, Hendrik

    Next to running machine learning algorithms based on inductive queries, much can be learned by immediately querying the combined results of many prior studies. Indeed, all around the globe, thousands of machine learning experiments are being executed on a daily basis, generating a constant stream of empirical information on machine learning techniques. While the information contained in these experiments might have many uses beyond their original intent, results are typically described very concisely in papers and discarded afterwards. If we properly store and organize these results in central databases, they can be immediately reused for further analysis, thus boosting future research. In this chapter, we propose the use of experiment databases: databases designed to collect all the necessary details of these experiments, and to intelligently organize them in online repositories to enable fast and thorough analysis of a myriad of collected results. They constitute an additional, queriable source of empirical meta-data based on principled descriptions of algorithm executions, without reimplementing the algorithms in an inductive database. As such, they engender a very dynamic, collaborative approach to experimentation, in which experiments can be freely shared, linked together, and immediately reused by researchers all over the world. They can be set up for personal use, to share results within a lab or to create open, community-wide repositories. Here, we provide a high-level overview of their design, and use an existing experiment database to answer various interesting research questions about machine learning algorithms and to verify a number of recent studies.

  19. The Experiment

    NASA Astrophysics Data System (ADS)

    Mariana Nicoara, Floare

    2016-04-01

    My name is Nicoara Floarea and I am teacher at Secondary School Calatele and I teach students from preparatory class and the second grade . They are six-eight years old. In my activity, for introducing scientific concepts to my students, I use various and active methods or traditional methods including experiments. The experiment stimulates students' curiosity, their creativity, the understanding and knowledge taught accessibility. I propose you two such experiments: The life cycle of the plants (long-term experiment, with rigorous observation time):We use beans, wheat or other; They are grown in pots and on the cotton soaked with water,keeping under students' observation protecting them ( just soak them regularly) and we waiting the plants rise. For discussions and comments of plant embryo development we use the plants which rose on the cotton soaked with water plants at the end of the first week. Last school year we had in the pot climbing beans which in May made pods. They were not too great but our experiment was a success. The students could deduce that there will develop those big beans which after drying will be planted again. The influence of light on plants (average duration experiment with the necessary observation time): We use two pots in which plants are of the same type (two geraniums), one of them is situated so as to get direct sunlight and other plant we put in a closed box. Although we wet both plants after a week we see that the plant that benefited from sunlight has turned strain in direct sunlight, developing normally in return the plant out of the box I have yellowed leaves, photosynthesis does not She has occurred . Students will understand the vital role of the Sun in plants' life, both in the classroom and in nature. The experiment is a method of teaching students extremely pleasant, with a remarkable percentage of acquiring more knowledge.

  20. Experiment 2042

    SciTech Connect

    Dash, Zora V.; Dennis, Bert R.; Dreesen, Donald S.; Fehler, Michael C.; House, Leigh S.; Walter, Fritz; Zyvoloski, George A.

    1984-09-10

    Experiment 2042, an injection test in EE-3, was conducted from May 15, 1984 through May 19, 1984. During this four day test ~2 million gallons of water were injected with a maximum injection rate of ~10BPM at 6000 psi. It was planned as a pumping test of the lower zone of well EE-3 (the open hole region from 11,400 ft to 11,648 ft) to test the reservoir characteristics and fracture-seismic system first created during Experiment 2025. However early in the experiment it became apparent that there was some sort connection between the lower zone and the upper "low pressure" zone in EE-3 (from the casing shoe at 10374 ft to about 10900 ft). Available information ruled out a packer failure or other direct connection between these zones so the experiment was continued as planned. Although not a major goal of the experiment, it was hoped that fractures would propagate from EE-3 to EE-2, so hydraulic communication could be established between the two wells, however this did not occur.

  1. Neutrino Experiments

    SciTech Connect

    McKeown, R. D.

    2010-08-04

    Recent studies of neutrino oscillations have established the existence of finite neutrino masses and mixing between generations of neutrinos. The combined results from studies of atmospheric neutrinos, solar neutrinos, reactor antineutrinos and neutrinos produced at accelerators paint an intriguing picture that clearly requires modification of the standard model of particle physics. These results also provide clear motivation for future neutrino oscillation experiments as well as searches for direct neutrino mass and nuclear double-beta decay. I will discuss the program of new neutrino oscillation experiments aimed at completing our knowledge of the neutrino mixing matrix.

  2. HEGRA Experiment

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    The La Palma cosmic-ray observatory HEGRA (High-Energy Gamma-Ray Astronomy) is an air shower experiment, located at the OBSERVATORIO DEL ROQUE DE LOS MUCHACHOS (2200 m above sea level, 28.75°N, 17.89°W) on the Canary island of La Palma, and is operated by institutes from Germany, Spain and Yerevan....

  3. Soil experiment

    NASA Technical Reports Server (NTRS)

    Hutcheson, Linton; Butler, Todd; Smith, Mike; Cline, Charles; Scruggs, Steve; Zakhia, Nadim

    1987-01-01

    An experimental procedure was devised to investigate the effects of the lunar environment on the physical properties of simulated lunar soil. The test equipment and materials used consisted of a vacuum chamber, direct shear tester, static penetrometer, and fine grained basalt as the simulant. The vacuum chamber provides a medium for applying the environmental conditions to the soil experiment with the exception of gravity. The shear strength parameters are determined by the direct shear test. Strength parameters and the resistance of soil penetration by static loading will be investigated by the use of a static cone penetrometer. In order to conduct a soil experiment without going to the moon, a suitable lunar simulant must be selected. This simulant must resemble lunar soil in both composition and particle size. The soil that most resembles actual lunar soil is basalt. The soil parameters, as determined by the testing apparatus, will be used as design criteria for lunar soil engagement equipment.

  4. Transport Experiments

    NASA Technical Reports Server (NTRS)

    Hall, Timothy M.; Wuebbles, Donald J.; Boering, Kristie A.; Eckman, Richard S.; Lerner, Jean; Plumb, R. Alan; Rind, David H.; Rinsland, Curtis P.; Waugh, Darryn W.; Wei, Chu-Feng

    1999-01-01

    MM II defined a series of experiments to better understand and characterize model transport and to assess the realism of this transport by comparison to observations. Measurements from aircraft, balloon, and satellite, not yet available at the time of MM I [Prather and Remsberg, 1993], provide new and stringent constraints on model transport, and address the limits of our transport modeling abilities. Simulations of the idealized tracers the age spectrum, and propagating boundary conditions, and conserved HSCT-like emissions probe the relative roles of different model transport mechanisms, while simulations of SF6 and C02 make the connection to observations. Some of the tracers are related, and transport diagnostics such as the mean age can be derived from more than one of the experiments for comparison to observations. The goals of the transport experiments are: (1) To isolate the effects of transport in models from other processes; (2) To assess model transport for realistic tracers (such as SF6 and C02) for comparison to observations; (3) To use certain idealized tracers to isolate model mechanisms and relationships to atmospheric chemical perturbations; (4) To identify strengths and weaknesses of the treatment of transport processes in the models; (5) To relate evaluated shortcomings to aspects of model formulation. The following section are included:Executive Summary, Introduction, Age Spectrum, Observation, Tropical Transport in Models, Global Mean Age in Models, Source-Transport Covariance, HSCT "ANOY" Tracer Distributions, and Summary and Conclusions.

  5. Chemistry Experiments

    NASA Technical Reports Server (NTRS)

    Brasseur, Guy; Remsberg, Ellis; Purcell, Patrick; Bhatt, Praful; Sage, Karen H.; Brown, Donald E.; Scott, Courtney J.; Ko, Malcolm K. W.; Tie, Xue-Xi; Huang, Theresa

    1999-01-01

    The purpose of the chemistry component of the model comparison is to assess to what extent differences in the formulation of chemical processes explain the variance between model results. Observed concentrations of chemical compounds are used to estimate to what degree the various models represent realistic situations. For readability, the materials for the chemistry experiment are reported in three separate sections. This section discussed the data used to evaluate the models in their simulation of the source gases and the Nitrogen compounds (NO(y)) and Chlorine compounds (Cl(y)) species.

  6. Asymmetric wetting of patterned surfaces composed of intrinsically hysteretic materials.

    PubMed

    Anantharaju, Neeharika; Panchagnula, Mahesh V; Vedantam, Srikanth

    2009-07-07

    Wetting of chemically heterogeneous surfaces is modeled using a phase field theory. We focus on a chemically heterogeneous surface composed of squares of one component material embedded in another. Unlike previous studies where the component materials were characterized only by an equilibrium contact angle, in this paper each of the component materials is constitutively allowed to exhibit hysteresis. Using this approach, we investigate the effect of heterogeneity length scale on observed macroscopic behavior. Cassie theory is found to be applicable only in the limit of vanishing length scale. For surfaces with a finite heterogeneity length scale, the advancing and receding contact angles deviate from Cassie theory. We find that this deviation and its length scale dependence are asymmetric and depend on the wetting properties of the embedded material relative to the contiguous substrate.

  7. Conditioning-induced elastic nonlinearity in hysteretic media

    NASA Astrophysics Data System (ADS)

    Gliozzi, A. S.; Scalerandi, M.; Antonaci, P.; Bruno, C. L. E.

    2010-08-01

    The definition and measurement of the nonlinear elastic properties of a sample is of great importance for a large number of applications, including characterization of material performances and damage detection. However, such measurements are often influenced by spurious effects due to a combination of nonlinearity and nonequilibrium phenomena. We will present experimental data to show how nonlinearity due to small cracks in concrete samples increases as a consequence of conditioning, i.e., after having perturbed them with a constant amplitude excitation. In addition, our experimental data highlight "memory effects," i.e., they show that when the excitation is removed, the elastic modulus does not return instantaneously to the initial value.

  8. Skylab Workshop experience in experiment accommodation

    NASA Technical Reports Server (NTRS)

    Hanlon, W. H.; Hassel, R. R.

    1974-01-01

    This paper examines the experiment support facilities available from the Orbital Workshop (OWS) module of the Skylab. Experiments and associated support provisions have been selected and described to illustrate the various accommodations and degree of complexities involved in the integration of these experiments into the Workshop. The interfaces described start with the simple and proceed to the complex. On the basis of the experience gained in integrating the experiments into the Workshop, conclusions are drawn and suggestions are made on ways to facilitate future experiment operations and at the same time simplify and reduce the cost of integration efforts.

  9. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1984

    1984-01-01

    Describes: (1) experiments using a simple phonocardiograph; (2) radioactivity experiments involving a VELA used as a ratemeter; (3) a 25cm continuously operating Foucault pendulum; and (4) camera control of experiments. Descriptions of equipment needed are provided when applicable. (JN)

  10. Solar Array Experiment (SAE) Flight Experience

    NASA Technical Reports Server (NTRS)

    Hill, H. C.; Young, L. E.; Turner, G. F.

    1985-01-01

    The space flight testing of a large, flat, flexible panel solar array is examined. The experiment objectives are: to demonstrate the functional operational of the wind deployment and packaging system; Electrical performance; Thermal performance; and dynamic performance. A complete description of the experiment and the flight results are given.

  11. The User Experience

    ERIC Educational Resources Information Center

    Schmidt, Aaron

    2010-01-01

    User experience (UX) is about arranging the elements of a product or service to optimize how people will interact with it. In this article, the author talks about the importance of user experience and discusses the design of user experiences in libraries. He first looks at what UX is. Then he describes three kinds of user experience design: (1)…

  12. Commercial Biomedical Experiments

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Experiments to seek solutions for a range of biomedical issues are at the heart of several investigations that will be hosted by the Commercial Instrumentation Technology Associates (ITA), Inc. Biomedical Experiments (CIBX-2) payload. CIBX-2 is unique, encompassing more than 20 separate experiments including cancer research, commercial experiments, and student hands-on experiments from 10 schools as part of ITA's ongoing University Among the Stars program. Valerie Cassanto of ITA checks the Canadian Protein Crystallization Experiment (CAPE) carried by STS-86 to Mir in 1997. The experiments are sponsored by NASA's Space Product Development Program (SPD).

  13. Commercial Biomedical Experiments Payload

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Experiments to seek solutions for a range of biomedical issues are at the heart of several investigations that will be hosted by the Commercial Instrumentation Technology Associates (ITA), Inc. The biomedical experiments CIBX-2 payload is unique, encompassing more than 20 separate experiments including cancer research, commercial experiments, and student hands-on experiments from 10 schools as part of ITA's ongoing University Among the stars program. Here, Astronaut Story Musgrave activates the CMIX-5 (Commercial MDA ITA experiment) payload in the Space Shuttle mid deck during the STS-80 mission in 1996 which is similar to CIBX-2. The experiments are sponsored by NASA's Space Product Development Program (SPD).

  14. Biomedical experiments. Part A: Biostack experiment

    NASA Technical Reports Server (NTRS)

    Buecker, H.; Horneck, G.; Reinholz, E.; Scheuermann, W.; Ruether, W.; Graul, E. H.; Planel, H.; Soleilhavoup, J. P.; Cuer, P.; Kaiser, R.

    1972-01-01

    The biostack experiment is described which was designed to study the biologic effects of individual heavy nuclei of galactic cosmic radiation during space flight outside the magnetosphere of the earth. Specifically, the biostack experiment was designed to promote research on the effects of high energy/high Z particles of galactic cosmic radiation on a broad spectrum of biologic systems, from the molecular to the highly organized and developed forms of life. The experiment was considered unique and scientifically meritorious because of its potential yield of information - currently unavailable on earth - on the interaction of biologic systems with the heavy particles of galactic cosmic radiation.

  15. Radiometer experiment for the aeroassist flight experiment

    NASA Astrophysics Data System (ADS)

    Davy, W. C.; Park, C.; Arnold, J. O.; Balakrishnan, A.

    1985-06-01

    A forthcoming NASA flight experiment is described that provides an opportunity to obtain a large base of radiometric data for high-altitude, high-velocity thermochemically nonequilibrated-flow conditions. As a preliminary to the design of a radiometer for this experiment, an approximate method for predicting both equilibrium and nonequilibrium radiative surface fluxes is described. Spectral results for one trajectory state, a velocity of 10 km/sec at an altitude of 85 km, are presented. These results are then used to develop some of the instrument parameters that will be needed for designing of the three genre of radiometers that are proposed for this experiment.

  16. Challenging Students with Experiments.

    ERIC Educational Resources Information Center

    Ambruso, Mark D.

    2003-01-01

    Supports the use of a science experiment option in the high school curriculum to enhance student learning. Presents a science experiment rubric and connects the use of science projects with standards. (DDR)

  17. Experiments in Magnetohydrodynamics

    ERIC Educational Resources Information Center

    Rayner, J. P.

    1970-01-01

    Describes three student experiments in magnetohydrodynamics (MHD). In these experiments, it was found that the electrical conductivity of the local water supply was sufficient to demonstrate effectively some of the features of MHD flowmeters, generators, and pumps. (LC)

  18. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1984

    1984-01-01

    Describes apparatus needed and instructions for conducting four experiments. Experiments focus on light waves, measurement of contact resistance, demonstration of longitudinal waves, and a simple method of measuring the refractive indices of transparent plates and liquids. (JM)

  19. Experiments and Calculations.

    ERIC Educational Resources Information Center

    Siddons, J. C.

    1982-01-01

    Discusses several science experiments/activities and their associated measurements. These include a simple projectile activity, cartesian diver (used to measure altitude and atmospheric pressure), experiment demonstrating atmospheric pressure, and activities using a stroboscope, and electrometer. (JN)

  20. More Experiments and Calculations.

    ERIC Educational Resources Information Center

    Siddons, J. C.

    1984-01-01

    Describes two experiments that illustrate basic ideas but would be difficult to carry out. Also presents activities and experiments on rainbow cups, electrical charges, electrophorus calculation, pulse electrometer, a skidding car, and on the Oersted effect. (JN)

  1. STEP Experiment Requirements

    NASA Technical Reports Server (NTRS)

    Brumfield, M. L. (Compiler)

    1984-01-01

    A plan to develop a space technology experiments platform (STEP) was examined. NASA Langley Research Center held a STEP Experiment Requirements Workshop on June 29 and 30 and July 1, 1983, at which experiment proposers were invited to present more detailed information on their experiment concept and requirements. A feasibility and preliminary definition study was conducted and the preliminary definition of STEP capabilities and experiment concepts and expected requirements for support services are presented. The preliminary definition of STEP capabilities based on detailed review of potential experiment requirements is investigated. Topics discussed include: Shuttle on-orbit dynamics; effects of the space environment on damping materials; erectable beam experiment; technology for development of very large solar array deployers; thermal energy management process experiment; photovoltaic concentrater pointing dynamics and plasma interactions; vibration isolation technology; flight tests of a synthetic aperture radar antenna with use of STEP.

  2. The Experiment Factory: Standardizing Behavioral Experiments.

    PubMed

    Sochat, Vanessa V; Eisenberg, Ian W; Enkavi, A Zeynep; Li, Jamie; Bissett, Patrick G; Poldrack, Russell A

    2016-01-01

    The administration of behavioral and experimental paradigms for psychology research is hindered by lack of a coordinated effort to develop and deploy standardized paradigms. While several frameworks (Mason and Suri, 2011; McDonnell et al., 2012; de Leeuw, 2015; Lange et al., 2015) have provided infrastructure and methods for individual research groups to develop paradigms, missing is a coordinated effort to develop paradigms linked with a system to easily deploy them. This disorganization leads to redundancy in development, divergent implementations of conceptually identical tasks, disorganized and error-prone code lacking documentation, and difficulty in replication. The ongoing reproducibility crisis in psychology and neuroscience research (Baker, 2015; Open Science Collaboration, 2015) highlights the urgency of this challenge: reproducible research in behavioral psychology is conditional on deployment of equivalent experiments. A large, accessible repository of experiments for researchers to develop collaboratively is most efficiently accomplished through an open source framework. Here we present the Experiment Factory, an open source framework for the development and deployment of web-based experiments. The modular infrastructure includes experiments, virtual machines for local or cloud deployment, and an application to drive these components and provide developers with functions and tools for further extension. We release this infrastructure with a deployment (http://www.expfactory.org) that researchers are currently using to run a set of over 80 standardized web-based experiments on Amazon Mechanical Turk. By providing open source tools for both deployment and development, this novel infrastructure holds promise to bring reproducibility to the administration of experiments, and accelerate scientific progress by providing a shared community resource of psychological paradigms.

  3. The Experiment Factory: Standardizing Behavioral Experiments

    PubMed Central

    Sochat, Vanessa V.; Eisenberg, Ian W.; Enkavi, A. Zeynep; Li, Jamie; Bissett, Patrick G.; Poldrack, Russell A.

    2016-01-01

    The administration of behavioral and experimental paradigms for psychology research is hindered by lack of a coordinated effort to develop and deploy standardized paradigms. While several frameworks (Mason and Suri, 2011; McDonnell et al., 2012; de Leeuw, 2015; Lange et al., 2015) have provided infrastructure and methods for individual research groups to develop paradigms, missing is a coordinated effort to develop paradigms linked with a system to easily deploy them. This disorganization leads to redundancy in development, divergent implementations of conceptually identical tasks, disorganized and error-prone code lacking documentation, and difficulty in replication. The ongoing reproducibility crisis in psychology and neuroscience research (Baker, 2015; Open Science Collaboration, 2015) highlights the urgency of this challenge: reproducible research in behavioral psychology is conditional on deployment of equivalent experiments. A large, accessible repository of experiments for researchers to develop collaboratively is most efficiently accomplished through an open source framework. Here we present the Experiment Factory, an open source framework for the development and deployment of web-based experiments. The modular infrastructure includes experiments, virtual machines for local or cloud deployment, and an application to drive these components and provide developers with functions and tools for further extension. We release this infrastructure with a deployment (http://www.expfactory.org) that researchers are currently using to run a set of over 80 standardized web-based experiments on Amazon Mechanical Turk. By providing open source tools for both deployment and development, this novel infrastructure holds promise to bring reproducibility to the administration of experiments, and accelerate scientific progress by providing a shared community resource of psychological paradigms. PMID:27199843

  4. Experiences with Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Dumbacher, Daniel L.

    2006-01-01

    The presentation "NASA Experience with Launch Vehicles" is a compilation of Mr. Dumbacher's career experiences with the Space Shuttle Program, the Delta - Clipper Experimental flight test project, the X-33 demonstrator project, and recent experiences with the Orbital Spaceplane Program agd the current NASA effort on Exploration Launch Systems. Mr. Dumbacher will discuss his personal experiences and provide lessons learned from each program. The accounts provided by Mr. Dumbacher are his own and do not necessarily represent the official NASA position.

  5. The ITALSAT experiment

    NASA Technical Reports Server (NTRS)

    Paraboni, A.

    1989-01-01

    Some information is given on the ITALSAT millimetric waves propagation experiment, which is to be conducted with the ITALSAT satellite, whose launch is foreseen for the middle of 1990. The purpose of the experiment is one of experimenting with advanced technologies and techniques employing the 20/30 GHz bands in wideband telecommunications. Among the most qualified features of this system are the multispot antenna and the exchange function performed directly onboard. Details of the experiment are given.

  6. NASTRAN: Users' experiences

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The proceedings of a conference on NASA Structural Analysis (NASTRAN) to analyze the experiences of users of the program are presented. The subjects discussed include the following: (1) statics and buckling, (2) vibrations and dynamics, (3) substructing, (4) new capability, (5) user's experience, and (6) system experience. Specific applications of NASTRAN to spacecraft, aircraft, nuclear power plants, and materials tests are reported.

  7. Theme: Supervised Experience.

    ERIC Educational Resources Information Center

    Cox, David E.; And Others

    1991-01-01

    Includes "It's Time to Stop Quibbling over the Acronym" (Cox); "Information Rich--Experience Poor" (Elliot et al.); "Supervised Agricultural Experience Selection Process" (Yokum, Boggs); "Point System" (Fraze, Vaughn); "Urban Diversity Rural Style" (Morgan, Henry); "Nonoccupational Supervised Experience" (Croom); "Reflecting Industry" (Miller);…

  8. Basic Experiments in Telecommunications.

    ERIC Educational Resources Information Center

    Andresen, S. G.

    Presented is a set of laboratory experiments developed to provide students with demonstrations and hands-on experiences with a variety of basic communications methods. These experiments may be used with students who have training in engineering, as well as those with social sciences who have no engineering background. Detailed exercises dealing…

  9. Using Experience for Learning.

    ERIC Educational Resources Information Center

    Boud, David, Ed.; And Others

    This book contains 13 articles on learning from experience and its relationship to adult learning and adult education. The introductory article, "Understanding Learning from Experience" (Boud, Cohen, Walker), examines five propositions about learning from experience. The following papers are organized into three sections that focus…

  10. Labor Market Experiment.

    ERIC Educational Resources Information Center

    Haupert, Michael J.

    1996-01-01

    Describes a class experiment where students search a hypothetical job market for jobs paying wages in a known range but with an unknown wage distribution. The experiment is divided into three "trials", each one introducing different variables (unemployment insurance, search costs, and recession). Includes experiment instructions and a…

  11. Graphing from Everyday Experience.

    ERIC Educational Resources Information Center

    Carraher, David; Schliemann, Analucia; Nemirousky, Ricardo

    1995-01-01

    Discusses the importance of teaching grounded in the everyday experiences and concerns of the learners. Studies how people with limited school experience can understand graphs and concludes that individuals with limited academic education can clarify the role of everyday experiences in learning about graphs. (ASK)

  12. The Concerned Observer Experiment.

    ERIC Educational Resources Information Center

    Rabiger, Michael

    1991-01-01

    Describes a classroom experiment--the "concerned observer" experiment--for production students that dramatizes basic film language by relating it to several levels of human observation. Details the experiment's three levels, and concludes that film language mimics wide-ranging states of human emotion and ideological persuasion. (PRA)

  13. Future Outlook: Experiment

    NASA Astrophysics Data System (ADS)

    Suzuki, Yoichiro

    2008-11-01

    The personal view for the next to the next neutrino detector, the ultimate experiment, is discussed. Considering the size, cost and head winds against the basic science, the ultimate experiment will be the only experiment in the world. Here two such experiments one for the neutrino oscillation and the other for the double beta decay were discussed. The ultimate experiment needs to include a bread and butter science and to have a discovery potential for an unexpected phenomenon. There are many technical challenges and international co-operations are absolutely necessary.

  14. Industrial application experiment series

    NASA Technical Reports Server (NTRS)

    Bluhm, S. A.

    1980-01-01

    The deployment of parabolic dish systems into the industrial sector for the purpose of providing users, suppliers, sponsors, and developers with a realistic assessment of system feasibility in selected near-term industrial applications will be accomplished initially through the industrial module experiment and later through additional experiments involving thermal, electric, and combined thermal and electrical systems. The approach is to progress through steps, from single module to multi-module systems, from thermal-only applications to more complex combined thermal and electric applications. The experience of other solar thermal experiments, particularly those involving parabolic dish hardware, will be utilized to the fullest extent possible in experiment planning and implementation.

  15. Gyroscope relativity experiment

    NASA Technical Reports Server (NTRS)

    Decher, R.

    1971-01-01

    A gyroscope test of general relativity theory is proposed. The basic ideas and hardware concepts conceived by the investigators to implement the experiment are discussed. The goal is to measure the extremely small relativistic precession of gyroscopes in an earth-orbiting satellite. The experiment hardware (cryogenic gyroscopes, a telescope and superconducting circuits) is enclosed in a liquid helium dewar. The experiment will operate in orbit for about one year.

  16. Microgravity Experiments On Animals

    NASA Technical Reports Server (NTRS)

    Dalton, B. P.; Leon, H.; Hogan, R.; Clarke, B.; Tollinger, D.

    1991-01-01

    Paper describes experiments on animal subjects planned for Spacelab Life Sciences 1 mission. Laboratory equipment evaluated, and physiological experiments performed. Represents first step in establishing technology for maintaining and manipulating rodents, nonhuman primates, amphibians, and plants during space flight without jeopardizing crew's environment. In addition, experiments focus on effects of microgravity on cardiopulmonary, cardiovascular, and musculoskeletal systems; on regulation of volume of blood and production of red blood cells; and on calcium metabolism and gravity receptors.

  17. Future reactor experiments

    SciTech Connect

    Wen, Liangjian

    2015-07-15

    The non-zero neutrino mixing angle θ{sub 13} has been discovered and precisely measured by the current generation short-baseline reactor neutrino experiments. It opens the gate of measuring the leptonic CP-violating phase and enables the neutrino mass ordering. The JUNO and RENO-50 proposals aim at resolving the neutrino mass ordering using reactors. The experiment design, physics sensitivity, technical challenges as well as the progresses of those two proposed experiments are reviewed in this paper.

  18. SEDS experiment design definition

    NASA Technical Reports Server (NTRS)

    Carroll, Joseph A.; Alexander, Charles M.; Oldson, John C.

    1990-01-01

    The Small Expendable-tether Deployment System (SEDS) was developed to design, build, integrate, fly, and safely deploy and release an expendable tether. A suitable concept for an on-orbit test of SEDS was developed. The following tasks were performed: (1) Define experiment objectives and requirements; (2) Define experiment concepts to reach those objectives; (3) Support NASA in experiment concept selection and definition; (4) Perform analyses and tests of SEDS hardware; (5) Refine the selected SEDS experiment concept; and (6) Support interactive SEDS system definition process. Results and conclusions are given.

  19. [Near death experiences].

    PubMed

    Rubia Vila, Francisco José

    2012-01-01

    Near Death Experiences are those accounted by people who after being clinically dead return to life spontaneously or after reanimation. These experiences have been used traditionally to support the belief in the existence of the soul and of life after death. However, today neuroscience tries to explain these experiences from the scientific point of view, i.e. explaining them based on their brain substrates. Their resemblance to mystic experiences and to altered states of consciousness seems to indicate that they may be produced by hyperactivity of limbic structures caused by anoxia or hypercapnia.

  20. Chemiluminescence: An Illuminating Experiment

    ERIC Educational Resources Information Center

    Gafney, Harry D.; Adamson, Arthur W.

    1975-01-01

    Describes an experiment in which luminescence is observed during a reaction between sodium borohydride and trisbipyridalruthenium (III). Includes a discussion of the theory of chemiluminescence. (MLH)

  1. Ball Collision Experiments

    ERIC Educational Resources Information Center

    Cross, R.

    2015-01-01

    Experiments are described on collisions between two billiard balls and between a bat and a ball. The experiments are designed to extend a student's understanding of collision events and could be used either as a classroom demonstration or for a student project.

  2. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1985

    1985-01-01

    Describes: (1) two experiments using a laser (resonant cavity for light and pinhole camera effect with a hologram); (2) optical differaction patterns displayed by microcomputer; and (3) automating the Hall effect (with comments on apparatus needed and computer program used); and (4) an elegant experiment in mechanical equilibrium. (JN)

  3. On the Poggendorff Experiment

    ERIC Educational Resources Information Center

    Coelho, Ricardo Lopes; Silva, P. A. S.; Borges, Paulo de Faria

    2015-01-01

    Poggendorff showed experimentally, in the middle of the 19th century, that the weight of an Atwood machine is reduced when it is brought to motion. His experiment has been revisited from time to time, making use of instrumentation that reflects the technological development of the moment. In this paper, the evolution of the experiment is briefly…

  4. Near-death experiences.

    PubMed Central

    Blackmore, S J

    1996-01-01

    Reactions to claims of near-death experiences (NDE) range from the popular view that this must be evidence for life after death, to outright rejection of the experiences as, at best, drug induced hallucinations or, at worse, pure invention. Twenty years, and much research, later, it is clear that neither extreme is correct. PMID:8683504

  5. Some Novel Fieldwork Experiments.

    ERIC Educational Resources Information Center

    Vincent, Julian F. V.; Kitchener, Andrew C.

    1988-01-01

    Describes results and experiences of four field-course experiments designed to explore the relationships between animals and their physical environment. Reports on the response of animals to flow rate of water, relationship between size and rate of locomotion, and mathematical and physical techniques used to study how animals live. (RT)

  6. Shusterman on Somatic Experience

    ERIC Educational Resources Information Center

    Maattanen, Pentti

    2010-01-01

    Richard Shusterman's "Body Consciousness" aims at formulating a theory of somaesthetics and somatic experience. There has indeed been a growing interest in the role of the body in experience. Shusterman examines the arguments of six important writers who have been influential in this discussion. The emphasis on the body is natural for a…

  7. Real-World Experiences

    ERIC Educational Resources Information Center

    Borja, Rhea R.

    2006-01-01

    This article presents IISME, a U.S. program that can give educators a real-world experience and that can deepen their subject-matter knowledge. It also presents the experiences of some teachers who are into this program. IISME's summer-fellowship program started out with 40 teachers and 12 companies. The group's growth picked up in 2001, when it…

  8. The Jumping Ring Experiment

    ERIC Educational Resources Information Center

    Baylie, M.; Ford, P. J.; Mathlin, G. P.; Palmer, C.

    2009-01-01

    The jumping ring experiment has become central to liquid nitrogen shows given as part of the outreach and open day activities carried out within the University of Bath. The basic principles of the experiment are described as well as the effect of changing the geometry of the rings and their metallurgical state. In general, aluminium rings are…

  9. Undergraduate Infrared Spectroscopy Experiments.

    ERIC Educational Resources Information Center

    MacCarthy, Patrick; Bowman, Susan J.

    1982-01-01

    Highlights procedures and results of an experiment using atomic absorption spectroscope to illustrate a fundamental chemical concept. The experiment demonstrates the dependence of the solubility product of lead sulfate on ionic strength in the presence of a slight excess of anion. (Author/JN)

  10. Human Simulated Diving Experiments.

    ERIC Educational Resources Information Center

    Bruce, David S.; Speck, Dexter F.

    1979-01-01

    This report details several simulated divinq experiments on the human. These are suitable for undergraduate or graduate laboratories in human or environmental physiology. The experiment demonstrates that a diving reflex is precipitated by both facial cooling and apnea. (Author/RE)

  11. Boyle's Law Experiment.

    ERIC Educational Resources Information Center

    Hermens, Richard A.

    1983-01-01

    Suggests that ideal experiments fit into course time constraints and be meaningful, relevant to course content, safe, inexpensive, simple, reproducible, and easy to set up/maintain. Describes a Boyle's Law experiment that uses a minimum of equipment and meets the foregoing criteria. Apparatus used, procedures, and safety precautions are…

  12. Corn blight watch experiment

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The corn blight problem is briefly described how the experiment was organized and conducted, the effect of the blight on the 1971 crop, and some conclusions that may be drawn as a result of the experiment. The information is based on preliminary reports of the Corn Blight Watch Steering Committee and incorporates much illustrative material conceived at Purdue University.

  13. Experiments in Science Teaching

    ERIC Educational Resources Information Center

    Hempstead, C. A.

    1973-01-01

    Analyzes the role of experiments in science teaching, and applies this analysis to the teaching of Millikan's experiment in physics. Critically examines an article written by T. J. Harvey entitled Millikan made easy'' which was previously published in The School Science Review. (JR)

  14. Experiment in Structural Learning.

    ERIC Educational Resources Information Center

    Diener, Z. P.

    The concern of the experiment is to find out the roles of abstraction and generalization in the learning of mathematical structures. The basic question is whether to generalize before abstracting or vice-versa in order to maximize transfer. The experiment involves four mathematical tasks and a transfer of activity. Experimental procedures are…

  15. Franklin: User Experiences

    SciTech Connect

    National Energy Research Supercomputing Center; He, Yun; Kramer, William T.C.; Carter, Jonathan; Cardo, Nicholas

    2008-05-07

    The newest workhorse of the National Energy Research Scientific Computing Center is a Cray XT4 with 9,736 dual core nodes. This paper summarizes Franklin user experiences from friendly early user period to production period. Selected successful user stories along with top issues affecting user experiences are presented.

  16. Science Experience Unit: Conservation.

    ERIC Educational Resources Information Center

    Ferguson-Florissant School District, Ferguson, MO.

    GRADES OR AGES: Intermediate grades. SUBJECT MATTER: Conservation. ORGANIZATION AND PHYSICAL APPEARANCE: The guide is divided into 24 experiments. It is mimeographed and staple-bound with a paper cover. OBJECTIVES AND ACTIVITIES: A specific skill or knowledge objective is stated at the beginning of each experiment. Detailed procedures are listed…

  17. Peak Experience Project

    ERIC Educational Resources Information Center

    Scott, Daniel G.; Evans, Jessica

    2010-01-01

    This paper emerges from the continued analysis of data collected in a series of international studies concerning Childhood Peak Experiences (CPEs) based on developments in understanding peak experiences in Maslow's hierarchy of needs initiated by Dr Edward Hoffman. Bridging from the series of studies, Canadian researchers explore collected…

  18. Seasat land experiments

    NASA Technical Reports Server (NTRS)

    Estes, J. E.; Barath, F.; Bryant, N.; Cannon, P. J.; Elachi, C.; Goetz, A.; Krishen, K.; Macdonald, H. C.; Marmelstein, A.; Miller, L. J.

    1978-01-01

    An overview of the Seasat land experiments is presented. The potential roles for active microwave imaging systems on board satellites were reviewed with particular emphasis on the Seasat Synthetic Aperture Radar (SAR). Recommendations were made concerning the type of experiments that could most profitably be conducted over land with the Seasat SAR system capabilities available.

  19. Experience with MODSIM II

    SciTech Connect

    Streets, J.; Berg, D.; Oleynik, G.; Pordes, R.; Slimmer, D.

    1992-02-01

    We present results of computer simulations for Data Acquisition systems for large fixed target experiments in an object oriented simulation language, MODSIM. This paper summarizes our experiences and presents preliminary results from the simulation already completed. We also indicate the resources required for this project.

  20. THX Experiment Overview

    NASA Technical Reports Server (NTRS)

    Wernet, Mark; Wroblewski, Adam; Locke, Randy; Georgiadis, Nick

    2016-01-01

    This presentation provides an overview of experiments conducted at NASA GRC to provide turbulent flow measurements needed for new turbulence model development and validation. The experiments include particle image velocimetry (PIV) and hot-wire measurements of mean flow velocity and temperature fields, as well as fluctuating components.

  1. Varieties of Musical Experience

    ERIC Educational Resources Information Center

    Bharucha, J. Jamshed; Curtis, Meagan; Paroo, Kaivon

    2006-01-01

    In this paper, we argue that music cognition involves the use of acoustic and auditory codes to evoke a variety of conscious experiences. The variety of domains that are encompassed by music is so diverse that it is unclear whether a single domain of structure or experience is defining. Music is best understood as a form of communication in which…

  2. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1980

    1980-01-01

    Describes briefly three experiments, which are presented by three physics teachers to share their ideas with other teachers and readers. These experiments are: (1) a simple hazemeter for window pollution assessment; (2) the speed of light; and (3) the ball-bearing electric motor. (HM)

  3. Nonparametric identification experiment

    NASA Technical Reports Server (NTRS)

    Yam, Yeung

    1988-01-01

    The following constitutes a summary of this paper: on-orbit identification methodology starts with nonparametric techniques for a priori system identification; development of the nonparametric identification and model determination experiment software has been completed; the validation experiments to be performed on the JPL Control and Identification Technology Validation Laboratory have been designed.

  4. MSFC Skylab corollary experiments

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The evolution of the development and integration of Skylab experiments from initial concepts through mission operations is documented. All experiment systems are covered as well as management controls which were developed and exercised to assure acceptable operational capability and optimize data acquisition for final scientific results.

  5. Beyond the Practicum Experience

    ERIC Educational Resources Information Center

    Williams, Jessica

    2009-01-01

    The practicum is an important part of most TESL programmes; however, many novice teachers seek practical experiences beyond the practicum as part of their preparation for entering the profession. Collaborative projects between language learners and pre-service language teachers can offer such valuable practical experiences for both groups. The…

  6. Hadron production experiments

    NASA Astrophysics Data System (ADS)

    Popov, Boris A.

    2013-02-01

    The HARP and NA61/SHINE hadroproduction experiments as well as their implications for neutrino physics are discussed. HARP measurements have already been used for predictions of neutrino beams in K2K and MiniBooNE/SciBooNE experiments and are also being used to improve the atmospheric neutrino flux predictions and to help in the optimization of neutrino factory and super-beam designs. First measurements released recently by the NA61/SHINE experiment are of significant importance for a precise prediction of the J-PARC neutrino beam used for the T2K experiment. Both HARP and NA61/SHINE experiments provide also a large amount of input for validation and tuning of hadron production models in Monte-Carlo generators.

  7. Extravehicular activity welding experiment

    NASA Technical Reports Server (NTRS)

    Watson, J. Kevin

    1989-01-01

    The In-Space Technology Experiments Program (INSTEP) provides an opportunity to explore the many critical questions which can only be answered by experimentation in space. The objective of the Extravehicular Activity Welding Experiment definition project was to define the requirements for a spaceflight experiment to evaluate the feasibility of performing manual welding tasks during EVA. Consideration was given to experiment design, work station design, welding hardware design, payload integration requirements, and human factors (including safety). The results of this effort are presented. Included are the specific objectives of the flight test, details of the tasks which will generate the required data, and a description of the equipment which will be needed to support the tasks. Work station requirements are addressed as are human factors, STS integration procedures and, most importantly, safety considerations. A preliminary estimate of the cost and the schedule for completion of the experiment through flight and postflight analysis are given.

  8. Health education telecommunications experiment

    NASA Technical Reports Server (NTRS)

    Whalen, A. A.

    1975-01-01

    The Health/Education Telecommunications Experiment (HET) was conducted jointly by NASA and HEW on NASA's ATS-6 communications satellite. This experiment actually consisted of six experiments testing health and education applications of a communication spacecraft producing a broadcast of color television directly from space to over 120 low-cost receivers located in remote rural areas throughout the U.S. (including Alaska). The experiments were conducted over the period from 2 July 1974 to 20 May 1975 and operated on an almost daily basis. The overall telecommunications system to support these experiments consisted of many elements: The ATS-6 spacecraft; five different types of earth stations consisting of 120 video receive terminals, 51 telephony tranceivers and eight video originating terminals of three different types. Actual performance of the equipment as measured in the field was shown to equal or exceed predicted values.

  9. Space Experiment Module (SEM)

    NASA Technical Reports Server (NTRS)

    Brodell, Charles L.

    1999-01-01

    The Space Experiment Module (SEM) Program is an education initiative sponsored by the National Aeronautics and Space Administration (NASA) Shuttle Small Payloads Project. The program provides nationwide educational access to space for Kindergarten through University level students. The SEM program focuses on the science of zero-gravity and microgravity. Within the program, NASA provides small containers or "modules" for students to fly experiments on the Space Shuttle. The experiments are created, designed, built, and implemented by students with teacher and/or mentor guidance. Student experiment modules are flown in a "carrier" which resides in the cargo bay of the Space Shuttle. The carrier supplies power to, and the means to control and collect data from each experiment.

  10. USML-1 Glovebox experiments

    NASA Technical Reports Server (NTRS)

    Naumann, Robert J.

    1995-01-01

    This report covers the development of and results from three experiments that were flown in the Materials Science Glovebox on USML-1: Marangoni convection in Closed Containers (MCCC), Double Float Zone (DFZ), and Fiber Pulling in Microgravity (FPM). The Glovebox provided a convenient, low cost method for doing simple 'try and see' experiments that could test new concepts or elucidate microgravity phenomena. Since the Glovebox provided essentially one (or possibly two levels of confinement, many of the stringent verification and test requirements on the experiment apparatus could be relaxed and a streamlined test and verification plan for flight qualification could be implemented. Furthermore, the experiments were contained in their own carrying cases whose external configurations could be identified early in the integration sequence for stowage considerations while delivery of the actual experiment apparatus could be postponed until only a few months before flight. This minimized the time fluids must be contained and reduced the possibility of corrosive reactions that could ruin the experiment. In many respects, this exercise was as much about developing a simpler, cheaper way of doing crew-assisted science as it was about the actual scientific accomplishments of the individual experiments. The Marangoni Convection in Closed Containers experiment was designed to study the effects of a void space in a simulated Bridgman crystal growth configuration and to determine if surface tension driven convective flows that may result from thermal gradients along any free surfaces could affect the solidification process. The Fiber Pulling in Microgravity experiment sought to separate the role of gravity drainage from capillarity effects in the break-up of slender cylindrical liquid columns. The Stability of a Double Float Zone experiment explored the feasibility of a quasi-containerless process in which a solidifying material is suspended by two liquid bridges of its own melt.

  11. Understanding customer experience.

    PubMed

    Meyer, Christopher; Schwager, Andre

    2007-02-01

    Anyone who has signed up for cell phone service, attempted to claim a rebate, or navigated a call center has probably suffered from a company's apparent indifference to what should be its first concern: the customer experiences that culminate in either satisfaction or disappointment and defection. Customer experience is the subjective response customers have to direct or indirect contact with a company. It encompasses every aspect of an offering: customer care, advertising, packaging, features, ease of use, reliability. Customer experience is shaped by customers' expectations, which largely reflect previous experiences. Few CEOs would argue against the significance of customer experience or against measuring and analyzing it. But many don't appreciate how those activities differ from CRM or just how illuminating the data can be. For instance, the majority of the companies in a recent survey believed they have been providing "superior" experiences to customers, but most customers disagreed. The authors describe a customer experience management (CEM) process that involves three kinds of monitoring: past patterns (evaluating completed transactions), present patterns (tracking current relationships), and potential patterns (conducting inquiries in the hope of unveiling future opportunities). Data are collected at or about touch points through such methods as surveys, interviews, focus groups, and online forums. Companies need to involve every function in the effort, not just a single customer-facing group. The authors go on to illustrate how a cross-functional CEM system is created. With such a system, companies can discover which customers are prospects for growth and which require immediate intervention.

  12. Radiochemical solar neutrino experiments

    NASA Astrophysics Data System (ADS)

    Gavrin, V. N.; Cleveland, B. T.

    2011-12-01

    Radiochemical experiments have been crucial to solar neutrino research. Even today, they provide the only direct measurement of the rate of the proton-proton fusion reaction, p+p→d+e++νe, which generates most of the Sun's energy. We first give a little history of radiochemical solar neutrino experiments with emphasis on the gallium experiment SAGE - the only currently operating detector of this type. The combined result of all data from the Ga experiments is a capture rate of 67.6±3.7 SNU. For comparison to theory, we use the calculated flux at the Sun from a standard solar model, take into account neutrino propagation from the Sun to the Earth and the results of neutrino source experiments with Ga, and obtain 67.3-3.5+3.9 SNU. Using the data from all solar neutrino experiments we calculate an electron neutrino pp flux of ϕpp♁=(3.41-0.77+0.76)×1010/(cm-s), which agrees well with the prediction from a detailed solar model of ϕpp♁=(3.30-0.14+0.13)×1010/(cm-s). Four tests of the Ga experiments have been carried out with very intense reactor-produced neutrino sources and the ratio of observed to calculated rates is 0.88±0.05. One explanation for this unexpectedly low result is that the cross section for neutrino capture by the two lowest-lying excited states in 71Ge has been overestimated. We end with consideration of possible time variation in the Ga experiments and an enumeration of other possible radiochemical experiments that might have been.

  13. Nightshade Prototype Experiments (Silverleaf)

    SciTech Connect

    Danielson, Jeremy; Bauer, Amy L.

    2016-12-23

    The Red Sage campaign is a series of subcritical dynamic plutonium experiments designed to measure ejecta. Nightshade, the first experiments in Red Sage scheduled for fiscal year 2019, will measure the amount of ejecta emission into vacuum from a double-­shocked plutonium surface. To address the major technical risks in Nightshade, a Level 2 milestone was developed for fiscal year 2016. Silverleaf, a series of four experiments, was executed at the Los Alamos National Laboratory in July and August 2016 to demonstrate a prototype of the Nightshade package and to satisfy this Level 2 milestone. This report is documentation that Red Sage Level 2 milestone requirements were successfully met.

  14. Advanced biostack experiment

    NASA Technical Reports Server (NTRS)

    Buecker, H.

    1981-01-01

    The Advanced Biostack Experiment is described. The objectives are: (1) to confirm, complement, and enlarge the information obtained from the previous experiments by applying improved and advanced methods of localization and physical and biological evaluation, performing advanced experiments based on these data, and including additional biological specimens and additional radiation detectors; (2) to determine the biological importance of nuclear disintegration stars; (3) to determine the interference of HZE particle induced effects with those of other space flight factors (e.g., weightlessness); and (4) to determine the distribution of HZE particles and of disintegration stars at different locations inside the module and on the pallet.

  15. THERMAL DISTRIBUTION SYSTEM EXPERIMENT

    SciTech Connect

    KRAJEWSKI,R.F.; ANDREWS,J.W.; WEI,G.

    1999-09-01

    A laboratory experiment has been conducted which tests for the effects of distribution system purging on system Delivery Effectiveness (DE) as defined in ASHRAE 152P. The experiment is described in its configuration, instrumentation, and data acquisition system. Data gathered in the experiment is given and discussed. The results show that purging of the distribution system alone does not offer any improvement of the system DE. Additional supporting tests were conducted regarding experimental simulations of buffer zones and bare pipe and are also discussed.

  16. Nimbus-5 ITPR Experiment.

    PubMed

    Smith, W L; Hilleary, D T; Fischer, J C; Howell, H B; Woolf, H M

    1974-03-01

    The Nimbus-5 infrared temperature profile radiometer (ITPR) experiment was designed to measure upwelling infrared radiation in appropriate spectral intervals and with sufficient geographical resolution for sounding the atmosphere's temperature distribution down to the earth's surface even under partly cloudy sky conditions. A primary scientific goal of the experiment was the specification of the mesoscale features of surface and atmospheric temperature and water vapor that are associated with intense weather systems. In this paper the ITPR instrument is described and some initial spacecraft results are given that demonstrate the success of the experiment in achieving its scientific goals.

  17. The three eggs experiment

    NASA Astrophysics Data System (ADS)

    Şahin Bülbül, Mustafa

    2016-01-01

    The three eggs experiment concerns 37 pre-service science teachers’ predictions about the impact shapes of three uncooked eggs dropped from different heights. This experiment looks at energy transformation from potential to kinetic energy, where the smaller parts of the egg shell spread far from the center of the impact. This experience encouraged the pre-service science teachers to use their familiar models, such as a fried egg, omelet, puddle, dropping or explosions, to explain their predictions. These models from everyday life presented can be used as a tool to explain unfamiliar phenomena.

  18. Industrial application experiment series

    NASA Technical Reports Server (NTRS)

    Bluhm, S. A.

    1981-01-01

    Two procurements within the Industrial Application Experiment Series of the Thermal Power Systems Project are discussed. The first procurement, initiated in April 1980, resulted in an award to the Applied Concepts Corporation for the Capital Concrete Experiment: two Fresnel concentrating collectors will be evaluated in single-unit installations at the Jet Propulsion Laboratory Parabolic Dish Test Site and at Capitol Concrete Products, Topeka, Kansas. The second procurement, initiated in March 1981, is titled, "Thermal System Engineering Experiment B." The objective of the procurement is the rapid deployment of developed parabolic dish collectors.

  19. Hydrothermal organic synthesis experiments

    NASA Technical Reports Server (NTRS)

    Shock, Everett L.

    1992-01-01

    Ways in which heat is useful in organic synthesis experiments are described, and experiments on the hydrothermal destruction and synthesis of organic compounds are discussed. It is pointed out that, if heat can overcome kinetic barriers to the formation of metastable states from reduced or oxidized starting materials, abiotic synthesis under hydrothermal conditions is a distinct possibility. However, carefully controlled experiments which replicate the descriptive variables of natural hydrothermal systems have not yet been conducted with the aim of testing the hypothesis of hydrothermal organic systems.

  20. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1988

    1988-01-01

    Describes three experiments: (1) "Liquid Flow from Orifices"; (2) "Microcomputer-Controlled Investigation of Battery Discharge and Recovery"; and (3) "Measurement of the Speed of Sound." Drawings and diagrams accompany each. (RT)

  1. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1989

    1989-01-01

    Introduced are two experiments: radon detection method shows real data using vacuum cleaner, soft toilet paper, and Geiger-Muller tube; critical potentials measurement describes the operation of Teltron tube with VELA. (YP)

  2. Experiments in Animal Behavior

    ERIC Educational Resources Information Center

    Polt, James M.

    1971-01-01

    Describes experiments in conditioning, sensory processes, social behavior, imprinting, innate preferences for color and form, and discrimination learning suitable for secondary school students. Mealworms, crickets, and chicks are used as subjects. (AL)

  3. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1979

    1979-01-01

    Explains how to demonstrate the following: the hysteresis effect and the existence of domains in Rochelle salt (sodium potassium tartrate); diffraction experiments using a slide with multiple slits; and an analogue technique for learning terminal velocity. (GA)

  4. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1988

    1988-01-01

    Describes four physics experiments including "Investigation of Box Resonances Using a Micro"; "A Direct Reading Wattmeter, DC or AC"; "Exercises in the Application of Ohm's Law"; and "Hysteresis on Gas Discharges." Discusses procedures, instrumentation, and analysis in each example. (CW)

  5. The Madison Dynamo Experiment

    NASA Astrophysics Data System (ADS)

    Kendrick, R. D.

    2005-10-01

    A spherical dynamo experiment has been constructed at the University of Wisconsin-Madison's liquid-sodium facility. The experiment is designed to self-generate magnetic fields from flows of conducting metal. The apparatus consists of a 1 m diameter, spherical stainless steel vessel filled with liquid sodium. Two 100 Hp motors drive impellers which generate the flow. The motors have been operated up to 1200 RPM (60% of design specification), achieving a magnetic Reynolds number of 130, based on impeller tip speed. Various polarizations of external magnetic fields have been applied to the sodium, and the induced magnetic field has been measured by both internal and external Hall probe arrays. Cavitation of the sodium is monitored using an ultrasonic transducer and suppressed through pressurization. Operating parameters and performance of the experiment are presented. Future plans for the experiment are discussed.

  6. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1986

    1986-01-01

    Describes (1) computer graphics for the coefficient of restitution; (2) an experiment on the optical processing of images; and (3) a simple, coherent optical system for character recognition using Polaroid (Type 665) negative film. (JN)

  7. Experiments with Helmholtz Resonators.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1996-01-01

    Presents experiments that use Helmholtz resonators and have been designed for a sophomore-level course in oscillations and waves. Discusses the theory of the Helmholtz resonator and resonance curves. (JRH)

  8. Foraging Experiences with Children

    ERIC Educational Resources Information Center

    Russell, Helen Ross

    1976-01-01

    Provided are foraging experiences and wild foods information for utilization in the urban school curriculum. Food uses are detailed for roses, dandelions, wild onions, acorns, cattails, violets and mints. (BT)

  9. A Sea Experience.

    ERIC Educational Resources Information Center

    Glickstein, Neil

    1989-01-01

    Described is a teacher education program organized by the Sea Education Association in Woods Hole (Massachusetts). The experience, including activities and examples of studies conducted, is discussed. Contact information for future cruises is included. (CW)

  10. Experimenting with Detergents

    ERIC Educational Resources Information Center

    Mitchell, Gail; Phillips, Donald B.

    1977-01-01

    Lists materials and procedures for experimenting with detergents. Included are methods for determination of the densities of dry detergents, ph values of detergent solutions, and a discussion of the ability of detergents to remove iodine stains from cloth. (CS)

  11. Dihalocarbene Insertion Experiment

    ERIC Educational Resources Information Center

    Goh, S. H.

    1975-01-01

    Describes the insertion reaction using the insertion of carbenes into carbon-hydrogen bonds as an example. Outlines an experiment that will illustrate dihalocarbene insertions into diisopropyl ether. (GS)

  12. ACTS mobile SATCOM experiments

    NASA Technical Reports Server (NTRS)

    Abbe, Brian S.; Frye, Robert E.; Jedrey, Thomas C.

    1993-01-01

    Over the last decade, the demand for reliable mobile satellite communications (satcom) for voice, data, and video applications has increased dramatically. As consumer demand grows, the current spectrum allocation at L-band could become saturated. For this reason, NASA and the Jet Propulsion Laboratory are developing the Advanced Communications Technology Satellites (ACTS) mobile terminal (AMT) and are evaluating the feasibility of K/Ka-band (20/30 GHz) mobile satcom to meet these growing needs. U.S. industry and government, acting as co-partners, will evaluate K/Ka-band mobile satcom and develop new technologies by conducting a series of applications-oriented experiments. The ACTS and the AMT testbed will be used to conduct these mobile satcom experiments. The goals of the ACTS Mobile Experiments Program and the individual experiment configurations and objectives are further presented.

  13. Experiments with a sunbird

    NASA Astrophysics Data System (ADS)

    Güémez, J.; Valiente, R.; Fiolhais, C.; Fiolhais, M.

    2003-12-01

    A theoretical description of the sunbird, a drinking bird without any external liquid, is compared with experiment. The transient times and the periods of oscillation given by a simulation of the dynamics agree with the measured values.

  14. Celestial mechanics experiment

    NASA Technical Reports Server (NTRS)

    Lorell, J.; Anderson, J. D.; Jordan, J. F.; Reasenberg, R. D.; Shapiro, I. I.

    1973-01-01

    The efforts and accomplishments of the CME Team are summarized. The objectives and experiment status, gravity field of Mars, test of general relativity, and the generation of normal points are discussed.

  15. A Colorful Experiment

    ERIC Educational Resources Information Center

    Hunter, C. Bruce

    1978-01-01

    This experiment, mixing solutions of potassium iodide and lead nitrate to give a bright yellow lead iodide precipitate, often leads students into other topics such as making paint from the precipitate. (BB)

  16. CCF Experiment #1

    NASA Video Gallery

    Images from CCF camera during Experiment #1, or EU#1, square groove geometry operations. The free surface, or gas/liquid interface, assumes a curved shape under subcritical flow conditions as its m...

  17. Packed Bed Reactor Experiment

    NASA Video Gallery

    The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

  18. Electrophoresis experiment for space

    NASA Technical Reports Server (NTRS)

    Vanderhoff, J. W.; Micale, F. J.

    1976-01-01

    The Apollo 16 electrophoresis experiment was analyzed, demonstrating that the separation of the two different-size monodisperse latexes did indeed take place, but that the separation was obscured by the pronounced electroosmotic flow of the liquid medium. The results of this experiment, however, were dramatic since it is impossible to carry out a similar separation on earth. It can be stated unequivocally from this experiment that any electrophoretic separation will be enhanced under microgravity conditions. The only question is the degree of this enhancement, which can be expected to vary from one experimental technique to another. The low-electroosmotic-mobility coating (Z6040-MC) developed under this program was found to be suitable for a free-fluid electrophoretic separation such as the experiment designed for the ASTP flight. The problem with this coating, however, is that its permanency is limited because of the slow desorption of the methylcellulose from the coated surface.

  19. Experimenting with Apostatic Selection.

    ERIC Educational Resources Information Center

    Allen, J. A.; Cooper, J. M.

    1988-01-01

    Reviewed is some of the experimental evidence for apostatic selection from work with artificial prey. Guidelines for further experiments are suggested including experimental design, analysis, variables, and selection in the wild. (Author/CW)

  20. Experiment-o-mania

    NASA Astrophysics Data System (ADS)

    Drndarski, Marina

    2015-04-01

    Every 21st century student is expected to develop science literacy skills. As this is not part of Serbian national curriculum yet, we decided to introduce it with this project. Experiment-o-mania provides students to experience science in different and exciting way. It makes opportunity for personalized learning offering space and time to ask (why, where, how, what if) and to try. Therefore, we empower young people with skills of experimenting, and they love science back. They ask questions, make hypothesis, make problems and solve them, make mistakes, discuss about the results. Subsequently this raises the students' interest for school curriculum. This vision of science teaching is associated with inquiry-based learning. Experiment-o-mania is the unique and recognizable teaching methodology for the elementary school Drinka Pavlović, Belgrade, Serbia. Experiment-o-mania implies activities throughout the school year. They are held on extra class sessions, through science experiments, science projects or preparations for School's Days of science. Students learn to ask questions, make observations, classify data, communicate ideas, conduct experiments, analyse results and make conclusions. All science teachers participate in designing activities and experiments for students in Experiment-o-mania teaching method. But they are not alone. Teacher of fine arts, English teachers and others also take part. Students have their representatives in this team, too. This is a good way to blend knowledge among different school subject and popularize science in general. All the experiments are age appropriate and related to real life situations, local community, society and the world. We explore Fibonacci's arrays, saving energy, solar power, climate change, environmental problems, pollution, daily life situations in the country or worldwide. We introduce great scientists as Nikola Tesla, Milutin Milanković and sir Isaac Newton. We celebrate all relevant international days, weeks

  1. Spacelab J experiment descriptions

    SciTech Connect

    Miller, T.Y.

    1993-08-01

    Brief descriptions of the experiment investigations for the Spacelab J Mission which was launched from the Kennedy Space Center aboard the Endeavour in Sept. 1992 are presented. Experiments cover the following: semiconductor crystals; single crystals; superconducting composite materials; crystal growth; bubble behavior in weightlessness; microgravity environment; health monitoring of Payload Specialists; cultured plant cells; effect of low gravity on calcium metabolism and bone formation; and circadian rhythm. Separate abstracts have been prepared for articles from this report.

  2. ISE structural dynamic experiments

    NASA Technical Reports Server (NTRS)

    Lock, Malcolm H.; Clark, S. Y.

    1988-01-01

    The topics are presented in viewgraph form and include the following: directed energy systems - vibration issue; Neutral Particle Beam Integrated Space Experiment (NPB-ISE) opportunity/study objective; vibration sources/study plan; NPB-ISE spacecraft configuration; baseline slew analysis and results; modal contributions; fundamental pitch mode; vibration reduction approaches; peak residual vibration; NPB-ISE spacecraft slew experiment; goodbye ISE - hello Zenith Star Program.

  3. Hamlet and psychoanalytic experience.

    PubMed

    Schwaber, Paul

    2007-01-01

    Hamlet draws us into its rendered world, enabling us to experience it with depth, awareness, and resonance, in a mode we recognize as aesthetic. By way of Shakespeare's play--primarily the first act--and a detailed case study, aesthetic and psychoanalytic experience are compared, to suggest that, for our own analytic discourse, we revalue Freud's unease that his case studies read like short stories.

  4. Spacelab J experiment descriptions

    NASA Technical Reports Server (NTRS)

    Miller, Teresa Y. (Editor)

    1993-01-01

    Brief descriptions of the experiment investigations for the Spacelab J Mission which was launched from the Kennedy Space Center aboard the Endeavour in Sept. 1992 are presented. Experiments cover the following: semiconductor crystals; single crystals; superconducting composite materials; crystal growth; bubble behavior in weightlessness; microgravity environment; health monitoring of Payload Specialists; cultured plant cells; effect of low gravity on calcium metabolism and bone formation; and circadian rhythm.

  5. Advanced Doppler tracking experiments

    NASA Technical Reports Server (NTRS)

    Armstrong, J. W.

    1989-01-01

    The Doppler tracking method is currently the only technique available for broadband gravitational wave searches in the approx. 10(exp -4) to 10(exp -1) Hz low frequency band. A brief review is given of the Doppler method, a discussion of the main noise sources, and a review of experience with current spacecraft and the prospects for sensitivity improvements in an advanced Doppler tracking experiment.

  6. Skylab sleep monitoring experiment (experiment M133)

    NASA Technical Reports Server (NTRS)

    Frost, J. D., Jr.

    1975-01-01

    A summary of the conceptual design of the Skylab sleep monitoring experiment and a comprehensive compilation of the data-analysis results from the three Skylab missions is presented. One astronaut was studied per flight, electroencephalographic, electro-oculographic, and headmotion signals acquired during sleep by use of an elastic recording cap containing sponge electrodes and an attached miniature preamplifier/accelerometer unit are shown. A control-panel assembly, mounted in the sleep compartment, tested electrodes, preserved analog signals, and automatically analyzed data in real time (providing a telemetered indication of sleep stage). Results indicate that men are able to obtain adequate sleep in regularly scheduled eight-hour rest periods during extended space missions.

  7. Bistability in Organic Magnetic Materials: A Comparative Study of the Key Differences between Hysteretic and Non-hysteretic Spin Transitions in Dithiazolyl Radicals.

    PubMed

    Vela, Sergi; Reardon, Michael B; Jakobsche, Charles E; Turnbull, Mark M; Ribas-Arino, Jordi; Novoa, Juan J

    2017-03-08

    Dithiazolyl (DTA)-based radicals have furnished many examples of organic spin-transition materials, some of them occurring with hysteresis and some others without. Herein, we present a combined computational and experimental study aimed at deciphering the factors controlling the existence or absence of hysteresis by comparing the phase transitions of 4-cyanobenzo-1,3,2-dithiazolyl and 1,3,5-trithia-2,4,6-triazapentalenyl radicals, which are prototypical examples of non-bistable and bistable spin transitions, respectively. Both materials present low-temperature diamagnetic and high-temperature paramagnetic structures, characterized by dimerized (⋅⋅⋅A-A⋅⋅⋅A-A⋅⋅⋅)n and regular (⋅⋅⋅A⋅⋅⋅A⋅⋅⋅A⋅⋅⋅A⋅⋅⋅)n π-stacks of radicals, respectively. We show that the regular π-stacks are not potential energy minima but average structures arising from a dynamic inter-conversion between two degenerate dimerized configurations: (⋅⋅⋅A-A⋅⋅⋅A-A⋅⋅⋅)n ↔(-A⋅⋅⋅A-A⋅⋅⋅A-)n . The emergence of this intra-stack dynamics upon heating gives rise to a second-order phase transition that is responsible for the change in the dominant magnetic interactions of the system. This suggests that the promotion of a (⋅⋅⋅A-A⋅⋅⋅A-A⋅⋅⋅)n ↔(-A⋅⋅⋅A-A⋅⋅⋅A-)n dynamics is a general mechanism for triggering spin transitions in DTA-based materials. Yet, this intra-stack dynamics does not suffice to generate bistability, which also requires a rearrangement of the intermolecular bonds between the π-stacks via a first-order phase transition.

  8. Modal identification experiment

    NASA Technical Reports Server (NTRS)

    Kvaternik, Raymond G.

    1992-01-01

    The Modal Identification Experiment (MIE) is a proposed on-orbit experiment being developed by NASA's Office of Aeronautics and Space Technology wherein a series of vibration measurements would be made on various configurations of Space Station Freedom (SSF) during its on-orbit assembly phase. The experiment is to be conducted in conjunction with station reboost operations and consists of measuring the dynamic responses of the spacecraft produced by station-based attitude control system and reboost thrusters, recording and transmitting the data, and processing the data on the ground to identify the natural frequencies, damping factors, and shapes of significant vibratory modes. The experiment would likely be a part of the Space Station on-orbit verification. Basic research objectives of MIE are to evaluate and improve methods for analytically modeling large space structures, to develop techniques for performing in-space modal testing, and to validate candidate techniques for in-space modal identification. From an engineering point of view, MIE will provide the first opportunity to obtain vibration data for the fully-assembled structure because SSF is too large and too flexible to be tested as a single unit on the ground. Such full-system data is essential for validating the analytical model of SSF which would be used in any engineering efforts associated with structural or control system changes that might be made to the station as missions evolve over time. Extensive analytical simulations of on-orbit tests, as well exploratory laboratory simulations using small-scale models, have been conducted in-house and under contract to develop a measurement plan and evaluate its potential performance. In particular, performance trade and parametric studies conducted as part of these simulations were used to resolve issues related to the number and location of the measurements, the type of excitation, data acquisition and data processing, effects of noise and nonlinearities

  9. National Flood Interoperability Experiment

    NASA Astrophysics Data System (ADS)

    Maidment, D. R.

    2014-12-01

    The National Flood Interoperability Experiment is led by the academic community in collaboration with the National Weather Service through the new National Water Center recently opened on the Tuscaloosa campus of the University of Alabama. The experiment will also involve the partners in IWRSS (Integrated Water Resources Science and Services), which include the USGS, the Corps of Engineers and FEMA. The experiment will address the following questions: (1) How can near-real-time hydrologic forecasting at high spatial resolution, covering the nation, be carried out using the NHDPlus or next generation geofabric (e.g. hillslope, watershed scales)? (2) How can this lead to improved emergency response and community resilience? (3) How can improved an improved interoperability framework support the first two goals and lead to sustained innovation in the research to operations process? The experiment will run from September 2014 through August 2015, in two phases. The mobilization phase from September 2014 until May 2015 will assemble the components of the interoperability framework. A Summer Institute to integrate the components will be held from June to August 2015 at the National Water Center involving faculty and students from the University of Alabama and other institutions coordinated by CUAHSI. It is intended that the insight that arises from this experiment will help lay the foundation for a new national scale, high spatial resolution, near-real-time hydrologic simulation system for the United States.

  10. Research by retrieving experiments.

    PubMed

    Blagosklonny, Mikhail V

    2007-06-01

    Newton did not discover that apples fall: the information was available prior to his gravitational hypothesis. Hypotheses can be tested not only by performing experiments but also by retrieving experiments from the literature (via PubMed, for example). Here I show how disconnected facts from known data, if properly connected, can generate novel predictions testable in turn by other published data. With examples from cell cycle, aging, cancer and other fields of biology and medicine, I discuss how new knowledge was and will be derived from old information. Millions of experiments have been already performed to test unrelated hypotheses and the results of those experiments are available to 'test' your hypotheses too. But most data (99% by some estimates) remain unpublished, because they were negative, seemed of low priority, or did not fit the story. Yet for other investigators those data may be valuable. The well-known story of Franklin and Watson is a case in point. By making preliminary data widely available, 'data-owners' will benefit most, receiving the credit for otherwise unused results. If posted (pre-published) on searchable databases, these data may fuel thousands of projects without the need for repetitive experiments. Enormous 'pre-published' databases coupled with Google-like search engines can change the structure of scientific research, and shrinking funding will make this inevitable.

  11. IBEX magnetic coupling experiments

    SciTech Connect

    Frost, C.A.; Kiekel, P.D.; Miller, R.B.; Ekdahl, C.A.; Wagner, J.; Ramirez, J.J.

    1985-01-01

    The magnetic coupling of one pulse to another is a key issue for some modes of high-current beam propagation. Experiments are in progress on Sandia's IBEX accelerator to address issues relevant to magnetic coupling. The IBEX experiments differ from previous experiments in that the B/sub theta/ field acting on the second pulse is the result of residual plasma current from the first pulse rather than current applied by an external means. This new feature makes the propagation sensitive to beam and plasma current profiles that are key to the physics of the magnetic coupling problem. These experiments do not attempt to study the air chemistry issues, as this would require much higher current densities than are available from IBEX. We are using the IBEX accelerator with a mismatched magnetized diode to produce two high-current pulses separated by approx.130 nsec. A pulse pair has been propagated over a 1.5-m path in low pressure air. Extraction of two pulses, each having different parameters, complicates the experiment but also provides new insight into the magnetic coupling proplem. 7 figs.

  12. Galileo Optical Experiment (GOPEX)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Two sets of laser pulses transmitted from Earth to a spacecraft over a distance of 1.4 million kilometers (870,000 miles) in a communications experiment are shown in this long-exposure image made by the Galileo spacecraft's imaging system. In the image, taken on Dec. 10, second day of the 8-day experiment, the sunlit part of the planet (west central United States) is to the right, the night side to the left. The camera was scanned from bottom to top of the frame (approximately south to north), smearing terrain features but showing individual pulses. The five larger spots in a vertical column near the pre-dawn centerline of the frame represent pulses from the U.S. Air Force Phillips Laboratory's Starfire Optical Range near Albuquerque, NM, at a pulse rate of 10 Hz. Those to the left are from the Jet Propulsion Laboratory's Table Mountain Observatory near Wrightwood, CA, at a rate of 15 Hz. Spots near the day/night terminator to the right are noise events not associated with the laser transmissions. The experiment, called GOPEX (Galileo Optical Experiment), is demonstrating a laser 'uplink' from Earth to spacecraft. Laser 'downlinks' may be used in the future to send large volumes of data from spacecraft to Earth. The experiment is operated by JPL's Tracking and Data Acquisition Technology Development Office for NASA's Office of Space Communications Advanced Systems Proqram.

  13. Cryogenic fluid management experiment

    NASA Technical Reports Server (NTRS)

    Eberhardt, R. N.; Bailey, W. J.; Fester, D. A.

    1981-01-01

    The cryogenic fluid management experiment (CFME), designed to characterize subcritical liquid hydrogen storage and expulsion in the low-q space environment, is discussed. The experiment utilizes a fine mesh screen fluid management device to accomplish gas-free liquid expulsion and a thermodynamic vent system to intercept heat leak and control tank pressure. The experiment design evolved from a single flight prototype to provision for a multimission (up to 7) capability. A detailed design of the CFME, a dynamic test article, and dedicated ground support equipment were generated. All materials and parts were identified, and components were selected and specifications prepared. Long lead titanium pressurant spheres and the flight tape recorder and ground reproduce unit were procured. Experiment integration with the shuttle orbiter, Spacelab, and KSC ground operations was coordinated with the appropriate NASA centers, and experiment interfaces were defined. Phase 1 ground and flight safety reviews were conducted. Costs were estimated for fabrication and assembly of the CFME, which will become the storage and supply tank for a cryogenic fluid management facility to investigate fluid management in space.

  14. FIRE Arctic Clouds Experiment

    NASA Technical Reports Server (NTRS)

    Curry, J. A.; Hobbs, P. V.; King, M. D.; Randall, D. A.; Minnis, P.; Issac, G. A.; Pinto, J. O.; Uttal, T.; Bucholtz, A.; Cripe, D. G.; Gerber, H.; Fairall, C. W.; Garrett, T. J.; Hudson, J.; Intrieri, J. M.; Jakob, C.; Jensen, T.; Lawson, P.; Marcotte, D.; Nguyen, L.

    1998-01-01

    An overview is given of the First ISCCP Regional Experiment (FIRE) Arctic Clouds Experiment that was conducted in the Arctic during April through July, 1998. The principal goal of the field experiment was to gather the data needed to examine the impact of arctic clouds on the radiation exchange between the surface, atmosphere, and space, and to study how the surface influences the evolution of boundary layer clouds. The observations will be used to evaluate and improve climate model parameterizations of cloud and radiation processes, satellite remote sensing of cloud and surface characteristics, and understanding of cloud-radiation feedbacks in the Arctic. The experiment utilized four research aircraft that flew over surface-based observational sites in the Arctic Ocean and Barrow, Alaska. In this paper we describe the programmatic and science objectives of the project, the experimental design (including research platforms and instrumentation), conditions that were encountered during the field experiment, and some highlights of preliminary observations, modelling, and satellite remote sensing studies.

  15. Experiments in Computing: A Survey

    PubMed Central

    Moisseinen, Nella

    2014-01-01

    Experiments play a central role in science. The role of experiments in computing is, however, unclear. Questions about the relevance of experiments in computing attracted little attention until the 1980s. As the discipline then saw a push towards experimental computer science, a variety of technically, theoretically, and empirically oriented views on experiments emerged. As a consequence of those debates, today's computing fields use experiments and experiment terminology in a variety of ways. This paper analyzes experimentation debates in computing. It presents five ways in which debaters have conceptualized experiments in computing: feasibility experiment, trial experiment, field experiment, comparison experiment, and controlled experiment. This paper has three aims: to clarify experiment terminology in computing; to contribute to disciplinary self-understanding of computing; and, due to computing's centrality in other fields, to promote understanding of experiments in modern science in general. PMID:24688404

  16. Experiments in computing: a survey.

    PubMed

    Tedre, Matti; Moisseinen, Nella

    2014-01-01

    Experiments play a central role in science. The role of experiments in computing is, however, unclear. Questions about the relevance of experiments in computing attracted little attention until the 1980s. As the discipline then saw a push towards experimental computer science, a variety of technically, theoretically, and empirically oriented views on experiments emerged. As a consequence of those debates, today's computing fields use experiments and experiment terminology in a variety of ways. This paper analyzes experimentation debates in computing. It presents five ways in which debaters have conceptualized experiments in computing: feasibility experiment, trial experiment, field experiment, comparison experiment, and controlled experiment. This paper has three aims: to clarify experiment terminology in computing; to contribute to disciplinary self-understanding of computing; and, due to computing's centrality in other fields, to promote understanding of experiments in modern science in general.

  17. Droplet Combustion Experiment movie

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Droplet Combustion Experiment (DCE) was designed to investigate the fundamental combustion aspects of single, isolated droplets under different pressures and ambient oxygen concentrations for a range of droplet sizes varying between 2 and 5 mm. The DCE principal investigator was Forman Williams, University of California, San Diego. The experiment was part of the space research investigations conducted during the Microgravity Science Laboratory-1 mission (STS-83, April 4-8 1997; the shortened mission was reflown as MSL-1R on STS-94). Advanced combustion experiments will be a part of investigations plarned for the International Space Station. (1.1 MB, 12-second MPEG, screen 320 x 240 pixels; downlinked video, higher quality not available)A still JPG composite of this movie is available at http://mix.msfc.nasa.gov/ABSTRACTS/MSFC-0300164.html.

  18. Electrophoresis experiments for space

    NASA Astrophysics Data System (ADS)

    Snyder, Robert S.; Rhodes, Percy H.

    2000-01-01

    It has long been hoped that space could alleviate the problems of large-scale, high-capacity electrophoresis. Support media and reduced chamber dimensions of capillary electrophoresis have established the physical boundaries for Earth-based systems. Ideally, electrophoresis conducted in a virtual weightless environment in an unrestricted ``free'' fluid should have great potential. The electrophoresis and isoelectric focusing experiments done in the reduced gravity over the past twenty-five years have demonstrated the absence of thermal convection and sedimentation as well as the presence of electrohydrodynamics that requires careful control. One commercial venture produced gram amounts of an electrophoretically purified protein during seven Space Shuttle flights but the market disappeared in the six years between experiment conception and performance on the Space Shuttle. Our accumulated experience in microgravity plus theoretical models predict improvements that should be possible with electrophoresis if past problems are considered and both invention of new technologies and innovation of procedures on the Space Station are encouraged. .

  19. Experiments in mixed reality

    NASA Astrophysics Data System (ADS)

    Krum, David M.; Sadek, Ramy; Kohli, Luv; Olson, Logan; Bolas, Mark

    2010-01-01

    As part of the Institute for Creative Technologies and the School of Cinematic Arts at the University of Southern California, the Mixed Reality lab develops technologies and techniques for presenting realistic immersive training experiences. Such experiences typically place users within a complex ecology of social actors, physical objects, and collections of intents, motivations, relationships, and other psychological constructs. Currently, it remains infeasible to completely synthesize the interactivity and sensory signatures of such ecologies. For this reason, the lab advocates mixed reality methods for training and conducts experiments exploring such methods. Currently, the lab focuses on understanding and exploiting the elasticity of human perception with respect to representational differences between real and virtual environments. This paper presents an overview of three projects: techniques for redirected walking, displays for the representation of virtual humans, and audio processing to increase stress.

  20. KISMET tungsten dispersal experiment

    SciTech Connect

    Wohletz, K.; Kunkle, T.; Hawkins, W.

    1996-12-01

    Results of the KISMET tungsten dispersal experiment indicate a relatively small degree of wall-rock contamination caused by this underground explosive experiment. Designed as an add-on to the KISMET test, which was performed in the U-1a.02 drift of the LYNER facility at Nevada Test Site on 1 March 1995, this experiment involved recovery and analysis of wall-rock samples affected by the high- explosive test. The chemical, high-explosive blast drove tungsten powder, placed around the test package as a plutonium analog, into the surrounding wall- rock alluvium. Sample analyses by an analytical digital electron microscope (ADEM) show tungsten dispersed in the rock as tiny (<10 {mu}m) particles, agglomerates, and coatings on alluvial clasts. Tungsten concentrations, measured by energy dispersive spectral analysis on the ADEM, indicate penetration depths less than 0.1 m and maximum concentrations of 1.5 wt % in the alluvium.

  1. Japanese Experiment Module (JEM)

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Japanese Experiment Module (JEM) pressure module is removed from its shipping crate and moved across the floor of the Space Station Processing Facility at Kennedy Space Center (KSC) to a work stand. A research laboratory, the pressurized module is the first element of the JEM, named 'Kibo' (Hope) to arrive at KSC. Japan's primary contribution to the International Space Station, the module will enhance unique research capabilities of the orbiting complex by providing an additional environment in which astronauts will conduct experiments. The JEM also includes an exposed facility or platform for space environment experiments, a robotic manipulator system, and two logistics modules. The various JEM components will be assembled in space over the course of three Shuttle missions.

  2. Future Experiments in Astrophysics

    NASA Technical Reports Server (NTRS)

    Krizmanic, John F.

    2002-01-01

    The measurement methodologies of astrophysics experiments reflect the enormous variation of the astrophysical radiation itself. The diverse nature of the astrophysical radiation, e.g. cosmic rays, electromagnetic radiation, and neutrinos, is further complicated by the enormous span in energy, from the 1.95 Kappa relic neutrino background to cosmic rays with energy greater than 10(exp 20)eV. The measurement of gravity waves and search for dark matter constituents are also of astrophysical interest. Thus, the experimental techniques employed to determine the energy of the incident particles are strongly dependent upon the specific particles and energy range to be measured. This paper summarizes some of the calorimetric methodologies and measurements planned by future astrophysics experiments. A focus will be placed on the measurement of higher energy astrophysical radiation. Specifically, future cosmic ray, gamma ray, and neutrino experiments will be discussed.

  3. An Organoleptic Laboratory Experiment

    NASA Astrophysics Data System (ADS)

    Risley, John M.

    1996-12-01

    Flavorings in foods and fragrances in personal care products is a topic often discussed in chemistry classes designed for the general education of non-science majors. A laboratory experiment has been designed to accompany the lecture topic. Compounds in ten different classes of organic molecules that are used in the fragrance and food industry are provided to students. Students whiff the vapors of each compound and describe the organoleptic properties using a set of terms utilized in the fragrance and food industry. A set of questions guides students to an understanding of the relationship between structure of molecules and smell. Students are permitted to create their own fragrance based on the results of the experiment. Student response has been favorable. The experiment rectifies misconceptions students have about structure and odor, and gives positive reinforcement to the lecture material.

  4. The Archimedes experiment

    NASA Astrophysics Data System (ADS)

    Calloni, E.; Caprara, S.; Laurentis, M. De; Esposito, G.; Grilli, M.; Majorana, E.; Pepe, G. P.; Petrarca, S.; Puppo, P.; Rapagnani, P.; Ricci, F.; Rosa, L.; Rovelli, C.; Ruggi, P.; Saini, N. L.; Stornaiolo, C.; Tafuri, F.

    2016-07-01

    Archimedes is an INFN-funded pathfinder experiment aimed at verifying the feasibility of measuring the interaction of vacuum fluctuations with gravity. The final experiment will measure the force exerted by the gravitational field on a Casimir cavity whose vacuum energy is modulated with a superconductive transition, by using a balance as a small force detector. Archimedes is two-year project devoted to test the most critical experimental aspects, in particular the balance resonance frequency and quality factor, the thermal modulation efficiency and the superconductive sample realization.

  5. Experiments with RHIC

    SciTech Connect

    Westfall, Gary D.

    2000-12-31

    Experiments with the Relativistic Heavy Ion Collider (RHIC) will begin in December 1999. RHIC consists of two superconducting rings capable of accelerating and storing Au beams of 100 GeV/nucleon and proton beams of 250 GeV. Four experiments are being prepared for RHIC: STAR, PHENIX, PHOBOS, and BRAHMS. These detector systems are designed to search for signals of the quark gluon plasma in Au-Au collisions. A spin physics program using polarized protons will also be carried out at RHIC.

  6. NOSL experiment support

    NASA Technical Reports Server (NTRS)

    Brook, M.

    1986-01-01

    An optical lightning detector was constructed and flown, along with Vinton cameras and a Fairchild Line Scan Spectrometer, on a U-2 during the summer of 1979. The U-2 lightning data was obtained in daylight, and was supplemented with ground truth taken at Langmuir Laboratory. Simulations were prepared as required to establish experiment operating procedures and science training for the astronauts who would operate the Night/Day Optical Survey of Thunderstorm Lightning (NOSL) equipment during the STS-2 NOSL experiment on the Space Shuttle. Data was analyzed and papers were prepared for publication.

  7. Ti Hemi boombox experiment

    SciTech Connect

    Miller, Phillip Isaac; Hull, Lawrence Mark

    2015-05-14

    Previous deformation experiments in which IR imaging was used pointed to a correlation in between IR signature in areas where heat was expected to be. The surface is not uniform during deformation experiments which cause cracks in the image in areas with increased temperature. To measure temperature under dynamic conditions, simultaneous reflectivity and radiance measurement under events of interest is needed. To measure a temperature measurement, a Reflectance measurement taken by framing camera at the edge of the camera sensitivity (700nm). Allows relative measurement at this wavelength. At reasonable temperatures the spectral radiance should peak near 2u and be 3-4 orders of magnitude higher than at 700 nm.

  8. Halogen lamp experiment, HALEX

    NASA Technical Reports Server (NTRS)

    Schmitt, G.; Stapelmann, J.

    1986-01-01

    The main purpose of the Halogen Lamp Experiment (HALEX) was to investigate the operation of a halogen lamp during an extended period in a microgravity environment and to prove its behavior in space. The Mirror Heating Facilities for Crystal Growth and Material Science Experiments in space relies on one or two halogen lamps as a furnace to melt the specimens. The HALEX aim is to verify: full power operation of a halogen lamp for a period of about 60 hours; achievement of about 10% of its terrestrial life span; and operation of the halogen lamp under conditions similar to furnace operation.

  9. World Ocean Circulation Experiment

    NASA Technical Reports Server (NTRS)

    Clarke, R. Allyn

    1992-01-01

    The oceans are an equal partner with the atmosphere in the global climate system. The World Ocean Circulation Experiment is presently being implemented to improve ocean models that are useful for climate prediction both by encouraging more model development but more importantly by providing quality data sets that can be used to force or to validate such models. WOCE is the first oceanographic experiment that plans to generate and to use multiparameter global ocean data sets. In order for WOCE to succeed, oceanographers must establish and learn to use more effective methods of assembling, quality controlling, manipulating and distributing oceanographic data.

  10. DEEP UNDERGROUND NEUTRINO EXPERIMENT

    SciTech Connect

    Wilson, Robert J.

    2016-03-03

    The Deep Underground Neutrino Experiment (DUNE) collaboration will perform an experiment centered on accelerator-based long-baseline neutrino studies along with nucleon decay and topics in neutrino astrophysics. It will consist of a modular 40-kt (fiducial) mass liquid argon TPC detector located deep underground at the Sanford Underground Research Facility in South Dakota and a high-resolution near detector at Fermilab in Illinois. This conguration provides a 1300-km baseline in a megawatt-scale neutrino beam provided by the Fermilab- hosted international Long-Baseline Neutrino Facility.

  11. Experiment in Water Dowsing

    DTIC Science & Technology

    1994-09-01

    0)0 "• •,• • -• )• .EEP C .7 7:i EXPERIMENT IN WATER DOWSING Til I"SIS EEDavid 1. (Gaisford. 1). E. AFIT/GEE/F.NS/94S-O I ~~m - DEPARTMENT... WATER DOWSING THESIS David I. Gaisford, P. E. AFIT/GEE/ENS/94S-01 Approved for Public Release; distribution unlimited =TC QUALITY pSP-ECTED 3 S0694-30622...Specils THESIS APPROVAL Student: David I. Gaisford Class: GEE 94S Thesis Title: Experiment in Water Dowsing Defense Date: 11 Aug 94 Committee Name

  12. Experiment SPHERE status 2008

    NASA Astrophysics Data System (ADS)

    Shaulov, S. B.; Besshapov, S. P.; Kabanova, N. V.; Sysoeva, T. I.; Antonov, R. A.; Anyuhina, A. M.; Bronvech, E. A.; Chernov, D. V.; Galkin, V. I.; Tkaczyk, W.; Finger, M.; Sonsky, M.

    2009-12-01

    The expedition carried out in March, 2008 to Lake Baikal became an important stage in the development of the SPHERE experiment. During the expedition the SPHERE-2 installation was hoisted, for the first time, on a tethered balloon, APA, to a height of 700 m over the lake surface covered with ice and snow. A series of test measurements were made. Preliminary results of the data processing are presented. The next plan of the SPHERE experiment is to begin a set of statistics for constructing the CR spectrum in the energy range 10-10 eV.

  13. Experiments in autonomous robotics

    SciTech Connect

    Hamel, W.R.

    1987-01-01

    The Center for Engineering Systems Advanced Research (CESAR) is performing basic research in autonomous robotics for energy-related applications in hazardous environments. The CESAR research agenda includes a strong experimental component to assure practical evaluation of new concepts and theories. An evolutionary sequence of mobile research robots has been planned to support research in robot navigation, world sensing, and object manipulation. A number of experiments have been performed in studying robot navigation and path planning with planar sonar sensing. Future experiments will address more complex tasks involving three-dimensional sensing, dexterous manipulation, and human-scale operations.

  14. Microwave PASER Experiment

    SciTech Connect

    Schoessow, P.; Kanareykin, A.; Antipov, S.; Poluektov, O.; Jing, C.

    2009-01-22

    The PASER (Particle Acceleration by Stimulated Emission of Radiation) concept for particle acceleration entails the direct transfer of energy from an active medium to a charged particle beam. The PASER was originally formulated for optical (laser) media; we are planning a PASER demonstration experiment based on an optically pumped X-band paramagnetic medium consisting of porphyrin or fullerene (C{sub 60}) derivatives in a toluene solution or polystyrene matrix. We discuss the background of this project and report on the status of the experiment to measure the acceleration of electrons using the microwave PASER.

  15. Microgravity ignition experiment

    NASA Technical Reports Server (NTRS)

    Motevalli, Vahid; Elliott, William; Garrant, Keith

    1992-01-01

    The purpose of this project is to develop a flight ready apparatus of the microgravity ignition experiment for the GASCan 2 program. This involved redesigning, testing, and making final modifications to the existing apparatus. The microgravity ignition experiment is intended to test the effect of microgravity on the time to ignition of a sample of alpha-cellulose paper. An infrared heat lamp is used to heat the paper sample within a sealed canister. The interior of the canister was redesigned to increase stability and minimize conductive heat transfer to the sample. This design was fabricated and tested and a heat transfer model of the paper sample was developed.

  16. Dual-domain mass-transfer parameters from electrical hysteresis: theory and analytical approach applied to laboratory, synthetic streambed, and groundwater experiments

    USGS Publications Warehouse

    Briggs, Martin; Day-Lewis, Frederick D.; Ong, John B.; Harvey, Judson W.; Lane, Jr., John W.

    2014-01-01

    Models of dual-domain mass transfer (DDMT) are used to explain anomalous aquifer transport behavior such as the slow release of contamination and solute tracer tailing. Traditional tracer experiments to characterize DDMT are performed at the flow path scale (meters), which inherently incorporates heterogeneous exchange processes; hence, estimated “effective” parameters are sensitive to experimental design (i.e., duration and injection velocity). Recently, electrical geophysical methods have been used to aid in the inference of DDMT parameters because, unlike traditional fluid sampling, electrical methods can directly sense less-mobile solute dynamics and can target specific points along subsurface flow paths. Here we propose an analytical framework for graphical parameter inference based on a simple petrophysical model explaining the hysteretic relation between measurements of bulk and fluid conductivity arising in the presence of DDMT at the local scale. Analysis is graphical and involves visual inspection of hysteresis patterns to (1) determine the size of paired mobile and less-mobile porosities and (2) identify the exchange rate coefficient through simple curve fitting. We demonstrate the approach using laboratory column experimental data, synthetic streambed experimental data, and field tracer-test data. Results from the analytical approach compare favorably with results from calibration of numerical models and also independent measurements of mobile and less-mobile porosity. We show that localized electrical hysteresis patterns resulting from diffusive exchange are independent of injection velocity, indicating that repeatable parameters can be extracted under varied experimental designs, and these parameters represent the true intrinsic properties of specific volumes of porous media of aquifers and hyporheic zones.

  17. AGS experiments, 1988, 1989, 1990

    SciTech Connect

    Depken, J.C.

    1991-04-01

    This report contains: experimental areas layout; table of beam parameters and fluxes; experiment schedule as run''; experiment long range schedule; a listing of experiments by number; two-page summaries of each experiment begin here, also ordered by number; publications of AGS experiments; and list of experimenters.

  18. AGS experiments: 1985, 1986, 1987

    SciTech Connect

    Depken, J.C.

    1987-01-01

    This report contains: Experimental areas layout, table of beam parameters and fluxes, experiment schedule ''as run,'' experiment long range schedule, a listing of experiments by number, two-page summaries of each experiment, also ordered by number, and publications of AGS experiments, 1982-1987.

  19. A Simple Adsorption Experiment

    ERIC Educational Resources Information Center

    Guirado, Gonzalo; Ayllon, Jose A.

    2011-01-01

    The study of adsorption phenomenon is one of the most relevant and traditional physical chemistry experiments performed by chemistry undergraduate students in laboratory courses. In this article, we describe an easy, inexpensive, and straightforward way to experimentally determine adsorption isotherms using pieces of filter paper as the adsorbent…

  20. Virtual Inquiry Experiences

    ERIC Educational Resources Information Center

    Harlow, Danielle; Nilsen, Katy

    2011-01-01

    Children in classrooms and scientists in laboratories engage in similar activities: they observe, ask questions, and try to explain phenomena. Video conferencing technology can remove the wall between the classroom and the laboratory, bringing children and scientists together. Virtual experiences and field trips can provide many of the benefits of…

  1. Experiments in ESP.

    ERIC Educational Resources Information Center

    Guerin, Stephen M.; Guerin, Clark L.

    1979-01-01

    Discusses a phenomenon called Extrasensory Perception (ESP) whereby information is gained directly by the mind without the use of the ordinary senses. Experiments in ESP and the basic equipment and methods are presented. Statistical evaluation of ESP experimental results are also included. (HM)

  2. The ALARM Experiment

    ERIC Educational Resources Information Center

    Gerhardt, Ira

    2015-01-01

    An experiment was conducted over three recent semesters of an introductory calculus course to test whether it was possible to quantify the effect that difficulty with basic algebraic and arithmetic computation had on individual performance. Points lost during the term were classified as being due to either algebraic and arithmetic mistakes…

  3. Experiments with Aspirin.

    ERIC Educational Resources Information Center

    Borer, Londa L.; Barry, Edward

    2000-01-01

    Presents a series of experiments that can be used to demonstrate how aspirin can be synthesized and characterized, how the hydrolysis of aspirin can be used as an introduction to kinetics, and how coordination chemistry (chelation) can be introduced by preparing and characterizing the copper complexes of aspirin and salicylic acid. (Contains over…

  4. The Group Experience

    ERIC Educational Resources Information Center

    Wadsworth, John

    2008-01-01

    Knowledge of group dynamics and leadership activities is a component of the CORE Standards for the Master's degree curriculum in Rehabilitation Counseling. A group experience is often included as a learning activity in rehabilitation counselor education curricula as an instructional method of imparting knowledge of group dynamics. Group experience…

  5. Thermal Control Surfaces Experiment

    NASA Technical Reports Server (NTRS)

    Wilkes, D. R.

    1999-01-01

    This report is the final experiment report for the TCSE and summarizes many years of hardware development and analyses. Also included are analyses presented in a number of TCSE papers that were prepared and given at scientific conferences including three LDEF Post-Retrieval Symposiums.

  6. A cosmic rays experiment

    NASA Astrophysics Data System (ADS)

    Pérez Munguía, Gustavo; Pineda de Carías, María Cristina

    1995-01-01

    In this paper we present the results of an experiment performed to detect the total flux of muons incident over Tegucigalpa (Honduras) the day of the total solar eclipse of the 11 July, 1991; and also a comparison with data obtained before the eclipse and registered in the past years.

  7. The Majorana Experiment

    SciTech Connect

    Aalseth, Craig E.; Aguayo Navarrete, Estanislao; Amman, M.; Avignone, F. T.; Back, Henning O.; Bai, Xinhua; Barabash, Alexander S.; Barbeau, P. S.; Bergevin, M.; Bertrand, F.; Boswell, M.; Brudanin, V.; Bugg, William; Burritt, Tom H.; Busch, Matthew; Capps, Greg L.; Chan, Yuen-Dat; Collar, J. I.; Cooper, R. J.; Creswick, R.; Detwiler, Jason A.; Diaz, J.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, S. R.; Ely, James H.; Esterline, James H.; Farach, H. A.; Fast, James E.; Fields, N.; Finnerty, P.; Fraenkle, Florian; Gehman, Victor M.; Giovanetti, G. K.; Green, M.; Guiseppe, Vincente; Gusey, K.; Hallin, A. L.; Harper, Gregory; Hazama, R.; Henning, Reyco; Hime, Andrew; Hong, H.; Hoppe, Eric W.; Hossbach, Todd W.; Howard, Stanley; Howe, M. A.; Johnson, R. A.; Keeter, K.; Keillor, Martin E.; Keller, C.; Kephart, Jeremy D.; Kidd, M. F.; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; LaRoque, B. H.; Leviner, L.; Loach, J. C.; Luke, P.; MacMullin, S.; Marino, Michael G.; Martin, R. D.; Medlin, D.; Mei, Dong-Ming; Miley, Harry S.; Miller, M. L.; Mizouni, Leila; Myers, Allan W.; Nomachi, Masaharu; Orrell, John L.; Peterson, David; Phillips, D.; Poon, Alan; Perevozchikov, O.; Perumpilly, Gopakumar; Prior, Gersende; Radford, D. C.; Reid, Douglas J.; Rielage, Keith; Robertson, R. G. H.; Rodriguez, Larry; Ronquest, M. C.; Salazar, Harold; Schubert, Alexis G.; Shima, T.; Shirchenko, M.; Sobolev, V.; Steele, David; Strain, J.; Swift, Gary; Thomas, K.; Timkin, V.; Tornow, W.; Van Wechel, T. D.; Vanyushin, I.; Varner, R. L.; Vetter, Kai; Vorren, Kris R.; Wilkerson, J. F.; Wolfe, B. A.; Xiang, W.; Yakushev, E.; Yaver, Harold; Young, A.; Yu, Chang-Hong; Yumatov, V.; Zhang, C.

    2011-08-01

    The Majorana Collaboration is assembling an array of HPGe detectors to search for neutrinoless double-beta decay in 76Ge. Initially, Majorana aims to construct a prototype module to demonstrate the potential of a future 1-tonne experiment. The design and potential reach of this prototype Demonstrator module are presented.

  8. Experiment at Evergreen.

    ERIC Educational Resources Information Center

    Jones, Richard M.

    The philosophy and structure of programs of coordinated study at Evergreen State College from 1970 to 1980 are discussed, and comparisons are made to the experiment at the University of California, Berkeley, promoted by Joseph Tussman. Both programs are based on ideas suggested by Alexander Meiklejohn and his Experimental College at the University…

  9. Kelp growth experiments

    SciTech Connect

    North, W. J.

    1980-01-01

    Harvest yields obtainable from giant kelp plants that are adequately fertilized were investigated. The following topics are discussed: desirable characteristics in a candidate macroalga, and giant kelp as a candidate macroalga for ocean farming. Nutrient requirements, field experiments, and approaches to acquiring yield data are reviewed. (MHR)

  10. Experiments with Dipole Antennas

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2009-01-01

    Employment of a data-acquisition system for data collection and calculations makes experiments with antennas more convenient and less time consuming. The determined directional patterns of the dipole antennas of different lengths are in reasonable agreement with theory. The enhancement of the signal by using a reflector is demonstrated, and a…

  11. Rocket Auroral Correlator Experiment

    NASA Technical Reports Server (NTRS)

    LaBelle, James

    2003-01-01

    Dartmouth College provided a multi-channel high- and low- frequency wave receivers, including active sensors on deployable booms, to the Rocket Auroral Correlator Experiment launched from Poker Flat, Alaska, in January 2002. College also performed preliminary analysis of the data. Details are outlined in chronological order.

  12. Experiences of Collaborative Research

    ERIC Educational Resources Information Center

    Kahneman, Daniel

    2003-01-01

    The author's personal history of the research that led to his recognition in economics is described, focusing on the process of collaboration and on the experience of controversy. The author's collaboration with Amos Tversky dealt with 3 major topics: judgment under uncertainty, decision making, and framing effects. A subsequent collaboration,…

  13. Invisalign: early experiences.

    PubMed

    Joffe, L

    2003-12-01

    This article describes the Invisalign technique. It is based on the author's personal experience of over 60 cases started in the private practice setting. The technology behind Invisalign and its development is reviewed. The Invisalign clinical technique is described, and the advantages and disadvantages of using Invisalign are highlighted.

  14. Experiments with Patterns

    ERIC Educational Resources Information Center

    de Mestre, Neville

    2008-01-01

    This article presents a hands-on experiment that covers many areas of high school mathematics. Included are the notions of patterns, proof, triangular numbers and various aspects of problem solving. The problem involves the arrangements of a school of fish using split peas or buttons to represent the fish. (Contains 4 figures.)

  15. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1983

    1983-01-01

    An experiment on cooling by convection, holographic processes achieved using optical fibers and observation of magnetic domains are described. Also describes four demonstrations: mechanical resonance on air track, independence of horizontal/vertical motion, motion of sphere in fluid medium, and light scattering near the critical point. (JN)

  16. Elastic swimming II: Experiments

    NASA Astrophysics Data System (ADS)

    Yu, Tony; Lauga, Eric; Hosoi, Anette

    2006-03-01

    We consider the problem of swimming at low Reynolds number by oscillating an elastic filament in a viscous liquid, as investigated by Wiggins and Goldstein (1998, Phys Rev Lett). In this second part of the study, we present results of a series of experiments characterizing the performance of the propulsive mechanism.

  17. Ganges valley aerosol experiment.

    SciTech Connect

    Kotamarthi, V.R.; Satheesh, S.K.

    2011-08-01

    In June 2011, the Ganges Valley Aerosol Experiment (GVAX) began in the Ganges Valley region of India. The objective of this field campaign is to obtain measurements of clouds, precipitation, and complex aerosols to study their impact on cloud formation and monsoon activity in the region.

  18. Notes on Experiments.

    ERIC Educational Resources Information Center

    Physics Education, 1979

    1979-01-01

    Describes the following: use and construction of a lens-pinhole spatial filter assembly to produce expanded beams; how to modify a unilab V. L. F. oscillator to give variable frequencies between .1 Hz and 10 Hz; to use Crookes radiometer quantitatively; and an externally located, movable probe for plasma physics experiments, using conventional…

  19. Principal Experiences of Succession

    ERIC Educational Resources Information Center

    Steele, Farla Gay

    2015-01-01

    This multiple case study explored the experiences of school principals and the usefulness of Peters' (2011) succession planning model. Ten purposefully selected principals from varying grade levels were interviewed; none reported a formal succession plan, and all had been assistant principals. The study concluded the assistant principal position…

  20. Moments: The Foxfire Experience.

    ERIC Educational Resources Information Center

    Wigginton, Eliot

    The high school journalism teacher who initiated the Foxfire Project discusses the memorable learning experiences and community studies in which students are involved as they develop and publish the Foxfire magazines. The author describes the project objectives and the successfully implemented teaching techniques and learning activities so that…

  1. An NMR Kinetics Experiment.

    ERIC Educational Resources Information Center

    Kaufman, Don; And Others

    1982-01-01

    Outlines advantages of and provides background information, procedures, and typical student data for an experiment determining rate of hydration of p-methyoxyphenylacetylene (III), followed by nuclear magnetic resonance spectroscopy. Reaction rate can be adjusted to meet time framework of a particular laboratory by altering concentration of…

  2. Music: A Shared Experience.

    ERIC Educational Resources Information Center

    Dunn, Rosemary

    1992-01-01

    This paper describes how sixth form girls in England provided music experiences to young children (ages 3-9) with severe learning difficulties. The weekly sessions involve individual sessions and use of various instruments. The relationship of the music therapy program to the National Curriculum is noted. (DB)

  3. Review of PEP experiments

    SciTech Connect

    Goldhaber, G.

    1983-03-01

    Recent physics results from four PEP experiments: Mark II, MAC, DELCO, and TPC are presented herewith. The topics discussed deal with flavor tagging of charmed and bottom quarks, tau and D/sup 0/ lifetimes, Electroweak interference effects, searches for new particles and dE/dx measurements.

  4. Investigating the Human Experience

    ERIC Educational Resources Information Center

    Ducote, Richard L.; Peterson, Robert E.

    1975-01-01

    A project entitled "Investigating the Human Experience," which was funded by the National Endowment for the Humanities, enables the College of DuPage to conduct a series of free films in various off-campus facilities. Documentaries and recent TV specials are shown, followed by a group discussion moderated by an instructor from the…

  5. Experiences and Outcomes

    ERIC Educational Resources Information Center

    Marden, Nicole Y.; Ulman, Leslie G.; Wilson, Fiona S.; Velan, Gary M.

    2013-01-01

    Online formative assessments have become increasingly popular; however, formal evidence supporting their educational benefits is limited. This study investigated the impact of online feedback quizzes on the learning experiences and outcomes of undergraduate students enrolled in an introductory physiology course. Four quiz models were tested, which…

  6. [Environmental Education Experiences].

    ERIC Educational Resources Information Center

    Burke County Board of Education, Morganton, NC.

    Environmental/ecological experiences, appropriate for elementary grades, are presented in this compilation. Designed as individual units of study, they consider components of the natural environment and in particular the local environment of Burke County, North Carolina. Units are titled: Burke County in a Nutshell, Our Culture, A Tour of the…

  7. Parent Hearing Aid Experiences

    ERIC Educational Resources Information Center

    Munoz, Karen; Roberts, Mallory; Mullings, Day; Harward, Richard

    2012-01-01

    This study addresses parent experiences in obtaining and managing hearing aids for their young child. The purpose was to identify challenges parents encounter to determine what state agencies can do to improve parent access to amplification. Data were collected July through September of 2010; 40 parents of children ages birth to 3 years old…

  8. Science and Human Experience

    NASA Astrophysics Data System (ADS)

    Cooper, Leon N.

    2015-01-01

    Part I. Science and Society: 1. Science and human experience; 2. Does science undermine our values?; 3. Can science serve mankind?; 4. Modern science and contemporary discomfort: metaphor and reality; 5. Faith and science; 6. Art and science; 7. Fraud in science; 8. Why study science? The keys to the cathedral; 9. Is evolution a theory? A modest proposal; 10. The silence of the second; 11. Introduction to Copenhagen; 12. The unpaid debt; Part II. Thought and Consciousness: 13. Source and limits of human intellect; 14. Neural networks; 15. Thought and mental experience: the Turing test; 16. Mind as machine: will we rubbish human experience?; 17. Memory and memories: a physicist's approach to the brain; 18. On the problem of consciousness; Part III. On the Nature and Limits of Science: 19. What is a good theory?; 20. Shall we deconstruct science?; 21. Visible and invisible in physical theory; 22. Experience and order; 23. The language of physics; 24. The structure of space; 25. Superconductivity and other insoluble problems; 26. From gravity to light and consciousness: does science have limits?

  9. Science and Human Experience

    NASA Astrophysics Data System (ADS)

    Cooper, Leon N.

    2014-12-01

    Part I. Science and Society: 1. Science and human experience; 2. Does science undermine our values?; 3. Can science serve mankind?; 4. Modern science and contemporary discomfort: metaphor and reality; 5. Faith and science; 6. Art and science; 7. Fraud in science; 8. Why study science? The keys to the cathedral; 9. Is evolution a theory? A modest proposal; 10. The silence of the second; 11. Introduction to Copenhagen; 12. The unpaid debt; Part II. Thought and Consciousness: 13. Source and limits of human intellect; 14. Neural networks; 15. Thought and mental experience: the Turing test; 16. Mind as machine: will we rubbish human experience?; 17. Memory and memories: a physicist's approach to the brain; 18. On the problem of consciousness; Part III. On the Nature and Limits of Science: 19. What is a good theory?; 20. Shall we deconstruct science?; 21. Visible and invisible in physical theory; 22. Experience and order; 23. The language of physics; 24. The structure of space; 25. Superconductivity and other insoluble problems; 26. From gravity to light and consciousness: does science have limits?

  10. JPL solar power experiments

    NASA Technical Reports Server (NTRS)

    Yasui, R. K.

    1976-01-01

    Report describes evolution of photovoltaic power systems designed and built for terrestrial use. Discussion focuses on technological problems impeding further systems development. Experiments and test data on seven types of solar panels and six material test specimens are described in detail.

  11. The Doppler Pendulum Experiment

    ERIC Educational Resources Information Center

    Lee, C. K.; Wong, H. K.

    2011-01-01

    An experiment to verify the Doppler effect of sound waves is described. An ultrasonic source is mounted at the end of a simple pendulum. As the pendulum swings, the rapid change of frequency can be recorded by a stationary receiver using a simple frequency-to-voltage converter. The experimental results are in close agreement with the Doppler…

  12. Enhance Your Twitter Experience

    ERIC Educational Resources Information Center

    Miller, Shannon McClintock

    2010-01-01

    The author has been encouraging teachers, students, and others to join Twitter and build their personal learning networks (PLNs) ever since she delved into this great social networking site. In this article, she offers a few other tools and tips that can improve the Twitter experience of those who have opened up an account and dabbled a bit but…

  13. The Huck Finn Experience.

    ERIC Educational Resources Information Center

    Levesque, Bonnie; And Others

    This paper describes "The Huck Finn Experience," a high motivation interdisciplinary unit that takes students on a 6-week journey back to the life and times of Mark Twain through the fictional character of Huckleberry Finn. The unit described in the paper was designed for eighth-grade students but could be easily adapted to be successful…

  14. Personal Experiences of China

    ERIC Educational Resources Information Center

    Hessler, Peter; Bradeen, Ryan; Wang, Richard; Masalski, Kathleen Woods

    2010-01-01

    This article presents four stories of personal experiences of China. In "A Journey Between China's Past and Present," Peter Hessler, a former Peace Corps volunteer and author, highlights misconceptions between Chinese and Americans and the desire both peoples share for knowledge about one another. In "Life on Liberation…

  15. Experiment with Conical Pendulum

    ERIC Educational Resources Information Center

    Tongaonkar, S. S.; Khadse, V. R.

    2011-01-01

    Conical pendulum is similar to simple pendulum with the difference that the bob, instead of moving back and forth, swings around in a horizontal circle. Thus, in a conical pendulum the bob moves at a constant speed in a circle with the string tracing out a cone. This paper describes an experiment with conical pendulum, with determination of g from…

  16. Experiments on Photoconductivity

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2012-01-01

    Computer-assisted experiments with CdS and CdSe photoresistors are described. The most important characteristics of the photoresistors are determined: (i) the spectral response, (ii) the photocurrent versus incident radiant power, (iii) the rise and decay time constants and (iv) the frequency response to modulated light. The photoconductivity gain…

  17. Permeable membrane experiment

    NASA Technical Reports Server (NTRS)

    Slavin, Thomas J.; Cao, Tuan Q.; Kliss, Mark H.

    1993-01-01

    The purpose of the Permeable Membrane Experiment is to gather flight data on three areas of membrane performance that are influenced by the presence of gravity. These areas are: (1) Liquid/gas phase separation, (2) gas bubble interference with diffusion through porous membranes and (3) wetting characteristics of hydrophilic membrane surfaces. These data are important in understaning the behavior of membrane/liquid/gas interfaces where surface tension forces predominate. The data will be compared with 1-g data already obtained and with predicted micrograviity behavior. The data will be used to develop designs for phase separation and plant nutrient delivery systems and will be available to the life support community for use in developing technologies which employ membranes. A conceptual design has been developed to conduct three membrane experiments, in sequence, aboard a single Complex Autonomous Payload (CAP) carrier to be carried in the Shuttle Orbiter payload bay. One experiment is conducted for each of the three membrane performance areas under study. These experiments are discussed in this paper.

  18. Experiments in Free Fall

    ERIC Educational Resources Information Center

    Art, Albert

    2006-01-01

    A model lift containing a figure of Albert Einstein is released from the side of a tall building and its free fall is arrested by elastic ropes. This arrangement allows four simple experiments to be conducted in the lift to demonstrate the effects of free fall and show how they can lead to the concept of the equivalence of inertial and…

  19. FLORIDA TOWER FOOTPRINT EXPERIMENTS

    SciTech Connect

    WATSON,T.B.; DIETZ, R.N.; WILKE, R.; HENDREY, G.; LEWIN, K.; NAGY, J.; LECLERC, M.

    2007-01-01

    The Florida Footprint experiments were a series of field programs in which perfluorocarbon tracers were released in different configurations centered on a flux tower to generate a data set that can be used to test transport and dispersion models. These models are used to determine the sources of the CO{sub 2} that cause the fluxes measured at eddy covariance towers. Experiments were conducted in a managed slash pine forest, 10 km northeast of Gainesville, Florida, in 2002, 2004, and 2006 and in atmospheric conditions that ranged from well mixed, to very stable, including the transition period between convective conditions at midday to stable conditions after sun set. There were a total of 15 experiments. The characteristics of the PFTs, details of sampling and analysis methods, quality control measures, and analytical statistics including confidence limits are presented. Details of the field programs including tracer release rates, tracer source configurations, and configuration of the samplers are discussed. The result of this experiment is a high quality, well documented tracer and meteorological data set that can be used to improve and validate canopy dispersion models.

  20. Examining Latina College Experiences

    ERIC Educational Resources Information Center

    Romero, Amanda R.

    2012-01-01

    The purposes of this qualitative narrative study were to explore the potential areas of conflict Latina college students experience between their educational goals and traditional cultural gender roles and expectations. Participants were selected utilizing purposeful sampling methods. All participants were first-generation college students.…

  1. Revisiting Supervised Agricultural Experience.

    ERIC Educational Resources Information Center

    Camp, William G.; Clarke, Ariane; Fallon, Maureen

    2000-01-01

    A Delphi panel of 40 agricultural educators unanimously agreed that supervised agricultural experience should remain an integral component of the curriculum; a name change is not currently warranted. Categories recommended were agribusiness entrepreneurship, placement, production, research, directed school lab, communications, exploration, and…

  2. Cyclic Voltammetry Experiment.

    ERIC Educational Resources Information Center

    Van Benschoten, James J.; And Others

    1983-01-01

    Describes a three-part experiment designed to introduce cyclic voltammetry to graduate/undergraduate students. Part 1 demonstrates formal reduction potential, redox electron transfer, diffusion coefficient, and electrochemical reversibility. Part 2 investigates electrochemical behavior of acetaminophen. Part 3 examines such experimental variables…

  3. Experiments in Pulsed Ultrasonics

    ERIC Educational Resources Information Center

    Palmer, S. B.; Forster, G. A.

    1970-01-01

    Describes and apparatus designed to generate and detect pulsed ultrasonics in solids and liquids over the frequency range 1-20 MHz. Experiments are suggested for velocity of sound, elastic constant and ultrasonic attenuation measurements on various materials over a wide temperature range. The equipment should be useful for demonstration purposes.…

  4. Experiments on ferrimagnetism

    NASA Astrophysics Data System (ADS)

    Kraftmakher, Yaakov

    2013-03-01

    Ferrimagnetism undoubtedly deserves a proper place in the undergraduate laboratory on electricity and magnetism. Four student experiments on ferrimagnetism are considered: (i) the hysteresis loops and permeability of a ‘soft’ ferrite; (ii) the differential permeability versus a dc bias; (iii) the frequency dependence of the complex permeability and (iv) the electromagnetic interference suppression by ferrite chokes and beads. Two ferrite cores taken off a low-frequency choke and a power cord are used. The measurements are simple and straightforward and show the important properties of ferrites and their applications. The values of the permeability of the ferrite core determined in experiments (i)-(iii) are in reasonable agreement. The frequency dependence of the complex permeability of the ferrites is similar to that given by the manufacturers. The capability of absorbing electromagnetic waves in a definite frequency range shown in experiment (iv) demonstrates one of the principles of Stealth technology. The equipment necessary for the experiments can be found in many student laboratories.

  5. The Airplane Experiment.

    ERIC Educational Resources Information Center

    Larson, Lee; Grant, Roderick

    1991-01-01

    Presents an experiment to investigate centripetal force and acceleration that utilizes an airplane suspended on a string from a spring balance. Investigates the possibility that lift on the wings of the airplane accounts for the differences between calculated tension and measured tension on the string. (MDH)

  6. Experimenting with Guitar Strings

    ERIC Educational Resources Information Center

    LoPresto, Michael C.

    2006-01-01

    What follows is a description of a simple experiment developed in a non-mathematical general education science course on sound and light for fine arts students in which a guitar is used with data collection hardware and software to verify the properties of standing waves on a string.

  7. Notes on Experiments.

    ERIC Educational Resources Information Center

    Bligh, P. H.; And Others

    1988-01-01

    Introduces three physics experiments for high school and college classes. Topics include measuring the ratio of heat capacities using a microcomputer and a glass syringe, producing large electric sparks using a variation of a Leyden bucket, and observing transmission line behavior using television signals. Includes descriptions of materials and…

  8. Electrophoresis experiments in microgravity

    NASA Technical Reports Server (NTRS)

    Snyder, Robert S.; Rhodes, Percy H.

    1991-01-01

    The use of the microgravity environment to separate and purify biological cells and proteins has been a major activity since the beginning of the NASA Microgravity Science and Applications program. Purified populations of cells are needed for research, transplantation and analysis of specific cell constituents. Protein purification is a necessary step in research areas such as genetic engineering where the new protein has to be separated from the variety of other proteins synthesized from the microorganism. Sufficient data are available from the results of past electrophoresis experiments in space to show that these experiments were designed with incomplete knowledge of the fluid dynamics of the process including electrohydrodynamics. However, electrophoresis is still an important separation tool in the laboratory and thermal convection does limit its performance. Thus, there is a justification for electrophoresis but the emphasis of future space experiments must be directed toward basic research with model experiments to understand the microgravity environment and fluid analysis to test the basic principles of the process.

  9. Experiments with isomeric beams

    NASA Astrophysics Data System (ADS)

    Pfützner, M.; Grzywacz, R.; Lewitowicz, M.; Rykaczewski, K.

    1997-02-01

    The results of the search for μs-isomers performed with 112Sn and 86Kr beams at 60 MeV/nucleon with the LISE3 spectrometer at GANIL are summarized. Planned extension of these studies to high energy fragmentation reactions with the FRS separator at GSI is described. Some perspectives for experiments with isomeric beams at GSI are mentioned.

  10. Remote Agent Experiment

    NASA Technical Reports Server (NTRS)

    Benard, Doug; Dorais, Gregory A.; Gamble, Ed; Kanefsky, Bob; Kurien, James; Millar, William; Muscettola, Nicola; Nayak, Pandu; Rouquette, Nicolas; Rajan, Kanna; Norvig, Peter (Technical Monitor)

    2000-01-01

    Remote Agent (RA) is a model-based, reusable artificial intelligence (At) software system that enables goal-based spacecraft commanding and robust fault recovery. RA was flight validated during an experiment on board of DS1 between May 17th and May 21th, 1999.

  11. Microgravity ignition experiment

    NASA Technical Reports Server (NTRS)

    Motevalli, Vahid; Elliott, William; Garrant, Keith; Marcotte, Ryan

    1992-01-01

    The purpose of this project is to develop a flight-ready apparatus of the microgravity ignition experiment for the GASCAN 2 program. The microgravity ignition experiment is designed to study how a microgravity environment affects the time to ignition of a sample of alpha-cellulose paper. A microgravity environment will result in a decrease in the heat transferred from the sample due to a lack of convection currents, which would decrease time to ignition. A lack of convection current would also cause the oxygen supply at the sample not to be renewed, which could delay or even prevent ignition. When this experiment is conducted aboard GASCAN 2, the dominant result of the lack of ignition will be determined. The experiment consists of four canisters containing four thermocouples and a sensor to detect ignition of the paper sample. This year the interior of the canister was redesigned and a mathematical model of the heat transfer around the sample was developed. This heat transfer model predicts an ignition time of approximately 5.5 seconds if the decrease of heat loss from the sample is the dominant factor of the lack of convection currents.

  12. Microheater Array Boiling Experiment

    NASA Technical Reports Server (NTRS)

    Kim, Jungho; McQuillen, John; Balombin, Joe

    2002-01-01

    By conducting pool boiling tests in microgravity, the effect of buoyancy on the overall boiling process and the relative magnitude of other phenomena can be assessed. Data from KC-135 and sounding rocket experiments indicate little effect of gravity on boiling heat transfer at wall superheats below 25 C, despite vast differences in bubble behavior between gravity levels. In microgravity, a large primary bubble, surrounded by smaller satellite bubbles, moved over the surface, occasionally causing nucleation. Once formed, the primary bubble size remained constant for a given superheat, indicating evaporation at the bubble base is balanced with condensation on the bubble cap. The primary bubble's size increased with wall superheat. Most heaters under the primary bubble had low heat transfer rates, suggesting liquid dryout. Strong Marangoni convection developed in microgravity, forming a 'jet' into the bulk liquid that forced the bubble onto the heater. An experiment is being designed for the. Microgravity Science Glovebox. This experiment uses two 96 element microheater arrays, 2.7 and 7.0 mm in size. These heaters are individually controlled to operate at a constant temperature, measuring local heat fluxes as a function of time and space. Most boiling experiments operate at constant wall heat flux with larger heaters, allowing only time and space-averaged measurements. Each heater is about the bubble departure size in normal gravity, but significantly smaller than the bubble departure size in reduced gravity.

  13. Carbon monoxide pollution experiment

    NASA Technical Reports Server (NTRS)

    Bortner, M. H.; Dick, R.; Goldstein, H. W.; Grenda, R. N.

    1975-01-01

    The experiment is designed to obtain data for the investigation of mechanisms by which CO is removed from the earth's atmosphere. The approach uses an orbiting platform to remotely map global CO concentrations and determine vertical CO profiles using a correlation interferometer measurement technique. The instrument is capable of measuring CO over the range of expected atmospheric burdens and of measuring trace atmospheric constituents.

  14. DSWA calorimeter bomb experiments

    SciTech Connect

    Cunningham, B

    1998-10-01

    Two experiments were performed in which 25 grams of TNT were detonated inside an expended detonation calorimeter bomb. The bomb had a contained volume of approximately 5.28 liters. In the first experiment, the bomb was charged with 3 atmospheres of nitrogen. In the second, it was charged with 2.58 atmospheres (23.1 psi gage) of oxygen. In each experiment pressure was monitored over a period of approximately 1200 microseconds after the pulse to the CDU. Monitoring was performed via two 10,000 psi 102AO3 PCB high frequency pressure transducers mounted symmetrically in the lid of the calorimeter bomb. Conditioners used were PCB 482As. The signals from the transducers were recorded in digital format on a multi channel Tektronix scope. The sampling frequency was 10 Mhz (10 samples per microsecond). After a period of cooling following detonation, gas samples were taken and were subsequently submitted for analysis using gas mass spectrometry. Due to a late request for post shot measurement, it was only possible to make a rough estimate of the weight of debris (carbon) remaining in the calorimeter bomb following the second experiment.

  15. Experiments with Ultrasonic Transducers.

    ERIC Educational Resources Information Center

    Greenslade, Thomas R., Jr.

    1994-01-01

    Discusses the use of 40 kHz ultrasonic transducers to study wave phenomena. Determines that the resulting wavelength of 9 mm allows acoustic experiments to be performed on a tabletop. Includes transducer characteristics and activities on speed of sound, reflection, double- and single-slit diffraction, standing waves, acoustical zone plate, and…

  16. A Harmonic Motion Experiment

    ERIC Educational Resources Information Center

    Gluck, P.; Krakower, Zeev

    2010-01-01

    We present a unit comprising theory, simulation and experiment for a body oscillating on a vertical spring, in which the simultaneous use of a force probe and an ultrasonic range finder enables one to explore quantitatively and understand many aspects of simple and damped harmonic motions. (Contains 14 figures.)

  17. The Japanese containerless experiments

    NASA Technical Reports Server (NTRS)

    Azuma, Hisao

    1990-01-01

    There are three sets of Japanese containerless experiments. The first is Drop dynamics research. It consists of acoustic levitation and large amplitude drop oscillation. The second is Optical materials processing in an acoustic levitation furnace. And the third is Electrostatic levitator development by two different Japanese companies.

  18. A UNESCO Experiment.

    ERIC Educational Resources Information Center

    Journal of Communication, 1978

    1978-01-01

    The Symphonie Experiment Study Group reports on the experimental use of the Symphonie Satellite to link UNESCO headquarters in Paris with the Conference Centre in Nairobi, Kenya, during the nineteenth session of the General Conference. Evaluations are reported for the use of the satellite for telephone, telex, and facsimile communications. (JMF)

  19. A Vibrating String Experiment

    ERIC Educational Resources Information Center

    Tsutsumanova, Gichka; Russev, Stoyan

    2013-01-01

    A simple experiment demonstrating the excitation of a standing wave in a metal string is presented here. Several tasks using the set-up are considered, which help the students to better understand the standing waves, the interaction between electric current and magnetic field and the resonance phenomena. This can serve also as a good lecture…

  20. Experiments in Ice Physics.

    ERIC Educational Resources Information Center

    Martin, P. F.; And Others

    1978-01-01

    Describes experiments in ice physics that demonstrate the behavior and properties of ice. Show that ice behaves as an ionic conductor in which charge is transferred by the movement of protons, its electrical conductivity is highly temperature-dependent, and its dielectric properties show dramatic variation in the kilohertz range. (Author/GA)

  1. ATA beam director experiment

    SciTech Connect

    Lee, E.P.; Younger, F.C.; Cruz, G.E.; Nolting, E.

    1986-06-23

    This report describes beam director elements for an experiment at the Advanced Test Accelerator. The elements described include a vernier magnet for beam aiming, an achromat magnet, and an isolation system for the beam interface. These components are built at small scale for concept testing. (JDH)

  2. Experimenting with Electric Trains

    ERIC Educational Resources Information Center

    Wick, D. P.; Ramsdell, M. W.

    2007-01-01

    A simple experiment can be performed to characterize the relationship between applied voltage and velocity (steady state and transient) for an electric toy train. The results can be used by teams of students to solve a series of challenges in which they attempt to predict the performance of a particular train. Some sample challenges might include…

  3. Transformations of emotional experience.

    PubMed

    de Cortiñas, Lia Pistiner

    2013-06-01

    In this paper the author approaches mental pain and the problems in a psychoanalytic treatment of patients with difficulties in the psychic transformation of their emotional experiences. The author is interested in the symbolic failure related to the obstruction of development of phantasies, dreams, dream-thoughts, etc. She differentiates symbolization disturbances related to hypertrophic projective identification from a detention of these primitive communications and emotional isolation. She puts forward the conjecture that one factor in the arrest of this development is the detention of projective identifications and that, when this primitive means of communication is re-established in a container-contained relationship of mutual benefit, this initiates the development of a symbolization process that can replace the pathological 'protection'. Another hypothesis she develops is that of inaccessible caesuras that, associated with the detention of projective identification, obstruct any integrative or interactive movement. This caesura and the detention of projective identifications affect mental functions needed for dealing with mental pain. The personality is left with precarious mental equipment for transforming emotional experiences. How can a psychoanalytical process stimulate the development of creative symbolization, transforming the emotional experiences and leading towards mental growth? The author approaches the clinical problem with the metaphor of the psychic birth of emotional experience. The modulation of mental pain in a container-contained relationship is a central problem for the development of the human mind. For discovering and giving a meaning to emotional experience, the infant depends on reverie, a function necessary in order to develop an evolved consciousness capable of being aware, which is different from the rudimentary consciousness that perceives but does not understand. The development of mature mental equipment is associated with the

  4. Hydrothermal organic synthesis experiments

    NASA Technical Reports Server (NTRS)

    Shock, Everett L.

    1992-01-01

    The serious scientific debate about spontaneous generation which raged for centuries reached a climax in the nineteenth century with the work of Spallanzani, Schwann, Tyndall, and Pasteur. These investigators demonstrated that spontaneous generation from dead organic matter does not occur. Although no aspects of these experiments addressed the issue of whether organic compounds could be synthesized abiotically, the impact of the experiments was great enough to cause many investigators to assume that life and its organic compounds were somehow fundamentally different than inorganic compounds. Meanwhile, other nineteenth-century investigators were showing that organic compounds could indeed be synthesized from inorganic compounds. In 1828 Friedrich Wohler synthesized urea in an attempt to form ammonium cyanate by heating a solution containing ammonia and cyanic acid. This experiment is generally recognized to be the first to bridge the artificial gap between organic and inorganic chemistry, but it also showed the usefulness of heat in organic synthesis. Not only does an increase in temperature enhance the rate of urea synthesis, but Walker and Hambly showed that equilibrium between urea and ammonium cyanate was attainable and reversible at 100 C. Wohler's synthesis of urea, and subsequent syntheses of organic compounds from inorganic compounds over the next several decades dealt serious blows to the 'vital force' concept which held that: (1) organic compounds owe their formation to the action of a special force in living organisms; and (2) forces which determine the behavior of inorganic compounds play no part in living systems. Nevertheless, such progress was overshadowed by Pasteur's refutation of spontaneous generation which nearly extinguished experimental investigations into the origins of life for several decades. Vitalism was dealt a deadly blow in the 1950's with Miller's famous spark-discharge experiments which were undertaken in the framework of the Oparin

  5. Gross decontamination experiment report

    SciTech Connect

    Mason, R.; Kinney, K.; Dettorre, J.; Gilbert, V.

    1983-07-01

    A Gross Decontamination Experiment was conducted on various levels and surfaces of the TMI - Unit 2 reactor building in March 1982. The polar crane, D-rings, missile shields, refueling canals, refueling bridges, equipment, and elevations 305' and 347'-6'' were flushed with low pressure water. Additionally, floor surfaces on elevation 305' and floor surfaces and major pieces of equipment on elevation 347'-6'' were sprayed with high pressure water. Selective surfaces were decontaminated with a mechanical scrubber and chemicals. Strippable coating was tested and evaluated on equipment and floor surfaces. The effectiveness, efficiency, and safety of several decontamination techniques were established for the large, complex decontamination effort. Various decontamination equipment was evaluated and its effectiveness was documented. Decontamination training and procedures were documented and evaluated, as were the support system and organization for the experiment.

  6. The PHOBOS experiment

    SciTech Connect

    Betts, R.R.

    1995-08-01

    PHOBOS is an experiment designed to study Au-Au collisions at RHIC. The apparatus consists of a 4{pi} multiplicity array and two spectrometer arms. The experiment is designed to measure the polar and azimuthal angles of most particles produced in the collisions and whether they are charged particles or photons. For approximately 1% of these particles, the two spectrometer arms will measure their properties in great detail. This includes many of the particles near mid-rapidity which are expected to show the most striking effects of any new physics which may occur. PHOBOS has proceeded from the Letter of Intent stage through Proposal and Conceptual Design Review to Construction Approval. It is anticipated that data taking will commence in 1999 when RHIC first provides beam.

  7. Health Education Telecommunications Experiment

    NASA Technical Reports Server (NTRS)

    Whalen, A. A.

    1975-01-01

    The Health/Education Telecommunications Experiment carried out with Applications Technology Satellite-6 is described. The experiment tested the effectiveness of color television broadcasts to over 120 low-cost receivers in rural areas. Five types of earth stations were involved: receive-only terminals (ROT), an intensive terminal consisting of the ROT plus a VHF transmitter and receiver; comprehensive S and C-band terminals having the capability of transmitting the video signal plus four audio channels; and the main originating stations. Additional supporting elements comprise 120 video receive terminals, 51 telephony transceivers, and 8 video originating terminals of 3 different parts. Technical parameters were measured to within 1 dB of the calculated values.

  8. White Cliffs: Operating Experience

    NASA Technical Reports Server (NTRS)

    Kaneff, S.

    1984-01-01

    The fourteen dish white cliffs solar power station area is remote and subject to extreme environmental conditions, solution of the associated problems required careful and thoughtful attention and the application of resources. Notwithstanding the wide range and harshness of conditions, the difficulties caused by remoteness and the lack of a technological base and the need for relatively rapid demonstration of success, the project has had a very positive outcome. Qualitative and quantitative information and lessons are now available to enable considerable simplifications to be made for a new system, reducing both hardware and operation and maintenance costs. Experience and lessons are presented, particularly in relation to: system performance in various environmental conditions; design philosophies for collectors, the array, control systems, engine and plant; operation and maintenance strategies and cost reducing possibilities. Experience so far gives encouragement for the future of such paraboloidal dish systems in appropriate areas.

  9. Future flavour physics experiments

    PubMed Central

    2015-01-01

    The current status of flavour physics and the prospects for present and future experiments will be reviewed. Measurements in B‐physics, in which sensitive probes of new physics are the CKM angle γ, the Bs mixing phase ϕs, and the branching ratios of the rare decays B(s)0→μ+μ− , will be highlighted. Topics in charm and kaon physics, in which the measurements of ACP and the branching ratios of the rare decays K→πνν¯ are key measurements, will be discussed. Finally the complementarity of the future heavy flavour experiments, the LHCb upgrade and Belle‐II, will be summarised. PMID:26877543

  10. Experiments on excitation waves

    NASA Astrophysics Data System (ADS)

    Müller, S. C.

    Recent trends in the experimentation on chemical and biochemical excitation waves are presented. In the Belousov-Zhabotinsky reaction, which is the most suitable chemical laboratory system for the study of wave propagation in excitable medium, the efficient control of wave dynamics by electrical fields and by light illumination is illustrated. In particular, the effects of a feedback control are shown. Further new experiments in this system are concerned with three-dimensional topologies and boundary effects. Important biological applications are found in the aggregation of slime mould amoebae, in proton waves during oscillatory glycolysis, and in waves of spreading depression in neuronal tissue as studied by experiments in chicken retina. Numerical simulations with appropriate reaction-diffusion models complement a large number of these experimental findings.

  11. Experiments with probe masses

    PubMed Central

    Braginsky, V. B.

    2007-01-01

    It is reasonable to regard the experiments performed by C. Coulomb and H. Cavendish in the end of the 18th century as the beginning of laboratory experimental physics. These outstanding scientists have measured forces (accelerations) produced by electric charges and by gravitational “charges” on probe masses that were attached to torque balance. Among the variety of different research programs and projects existing today, experiments with probe masses are still playing an important role. In this short review, the achieved and planned sensitivities of very challenging LIGO (Laser Interferometer Gravitational wave Observatory) and LISA (Laser Interferometer Space Antennae) projects are described, and a list of nonsolved problems is discussed as well. The role of quantum fluctuations in high precision measurements is also outlined. Apart from these main topics, the limitations of sensitivity caused by cosmic rays and the prospects of clock frequency stability are presented. PMID:17296944

  12. Shooting Star Experiment

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Shooting Star Experiment (SSE) is designed to develop and demonstrate the technology required to focus the sun's energy and use the energy for inexpensive space Propulsion Research. Pictured is an engineering model (Pathfinder III) of the Shooting Star Experiment (SSE). This model was used to test and characterize the motion and deformation of the structure caused by thermal effects. In this photograph, alignment targets are being placed on the engineering model so that a theodolite (alignment telescope) could be used to accurately measure the deformation and deflections of the engineering model under extreme conditions, such as the coldness of deep space and the hotness of the sun as well as vacuum. This thermal vacuum test was performed at the X-Ray Calibration Facility because of the size of the test article and the capabilities of the facility to simulate in-orbit conditions

  13. Stirling machine operating experience

    NASA Technical Reports Server (NTRS)

    Ross, Brad; Dudenhoefer, James E.

    1991-01-01

    Numerous Stirling machines have been built and operated, but the operating experience of these machines is not well known. It is important to examine this operating experience in detail, because it largely substantiates the claim that Stirling machines are capable of reliable and lengthy lives. The amount of data that exists is impressive, considering that many of the machines that have been built are developmental machines intended to show proof of concept, and were not expected to operate for any lengthy period of time. Some Stirling machines (typically free-piston machines) achieve long life through non-contact bearings, while other Stirling machines (typically kinematic) have achieved long operating lives through regular seal and bearing replacements. In addition to engine and system testing, life testing of critical components is also considered.

  14. The gravitational wave experiment

    NASA Technical Reports Server (NTRS)

    Bertotti, B.; Ambrosini, R.; Asmar, S. W.; Brenkle, J. P.; Comoretto, G.; Giampieri, G.; Less, L.; Messeri, A.; Wahlquist, H. D.

    1992-01-01

    Since the optimum size of a gravitational wave detector is the wave length, interplanetary dimensions are needed for the mHz band of interest. Doppler tracking of Ulysses will provide the most sensitive attempt to date at the detection of gravitational waves in the low frequency band. The driving noise source is the fluctuations in the refractive index of interplanetary plasma. This dictates the timing of the experiment to be near solar opposition and sets the target accuracy for the fractional frequency change at 3.0 x 10 exp -14 for integration times of the order of 1000 sec. The instrumentation utilized by the experiment is distributed between the radio systems on the spacecraft and the seven participating ground stations of the Deep Space Network and Medicina. Preliminary analysis is available of the measurements taken during the Ulysses first opposition test.

  15. Cibola flight experiment

    SciTech Connect

    Roussel-Dupre, D.; Caffrey, M. P.

    2004-01-01

    Los Alamos National Laboratory is building the Cibola Flight Experiment (CFE), a reconfigurable processor payload intended for a Low Earth Orbit system. It will survey portions of the VHF and UHF radio spectra. The experiment uses networks of reprogrammable, Field Programmable Gate Arrays (FPGAs) to process the received signals for ionospheric and lightning studies. The objective is to validate the on-orbit use of commercial, reconfigurable FPGA technology utilizing several different single-event upset mitigation schemes. It will also detect and measure impulsive events that occur in a complex background. Surrey Satellite Technology, Ltd (SSTL) is building the small host satellite, CFESat, based upon SSTL's disaster monitoring constellation (DMC) and Topsat mission satellite designs. The CFESat satellite will be launched by the Space Test Program in September 2006 on the US Air Force Evolved Expendable Launch Vehicle (EELV) using the EELV's Secondary Payload Adapter (ESPA) that allows up to six small satellites to be launched as 'piggyback' passengers with larger spacecraft.

  16. Experimenting with Bulbs

    NASA Astrophysics Data System (ADS)

    Cavicchi, Elizabeth M.

    1998-04-01

    What questions come about as learners explore physical materials? How does their learning deepen through inventing experiments and making and testing their own interpretations? I present episodes from the investigatory work of three adult learners who met regularly with me to explore batteries, bulbs and wires. I taught by engaging the learners' interest in these materials and by interactively researching their developing understandings. As both teacher and researcher, I used what I learned about their understandings to support their efforts to extend the body of experimental knowledge they were developing. Development is evident in experimental details. Initially, by hand-holding, they light a bulb with a wire and battery. Later, in soldering connections, they wonder about the bulb's internal structure. They research thoughts about this through dissecting a bulb -- and lighting its exposed filament. Such experimenting changed thinking: from imagining sequential loops, to questioning electrical contacts, to inferring circuital paths.

  17. Electronics for Satellite Experiments

    SciTech Connect

    Johnson, Robert P.; /UC, Santa Cruz

    2006-05-16

    The tracking detector for the LAT science instrument on the GLAST mission is an example of a large-scale particle detection system built primarily by particle physicists for space flight within the context of a NASA program. The design and fabrication model in most ways reflected practice and experience from particle physics, but the quality assurance aspects were guided by NASA. Similarly, most of the electronics in the LAT as a whole were designed and built by staff at a particle physics lab. This paper reports on many of the challenges and lessons learned in the experience of designing and building the tracking detector and general LAT electronics for use in the NASA GLAST mission.

  18. The GLORIA demonstrator experiment

    NASA Astrophysics Data System (ADS)

    Majcher, A.; Ćwiek, A.; Ćwiok, M.; Mankiewicz, L.; Zaremba, M.; Żarnecki, A. F.

    2013-10-01

    GLORIA stands for "GLObal Robotic-telescopes Intelligent Array" and it is the first free and open-access network of robotic telescopes on the world. Based on a Web 2.0 environment amateur and professional users can do research in astronomy by observing with robotic telescopes, and/or analyzing data acquired with GLORIA, or from other free access databases. GLORIA project develops free standards, protocols and tools for controlling Robotic Telescopes and related instrumentation, for scheduling observations in the telescope network, and for conducting so-called off-line experiments based on the analysis of astronomical data. This contribution summarizes the implementation and results from the first research level off-line demonstrator experiment implemented in GLORIA, which was base on the data collected with the "Pi of the Sky" telescope in Chile.

  19. The NASA Experience

    NASA Technical Reports Server (NTRS)

    Ramos, Alberto

    2011-01-01

    Projects assigned to: (1) Testing, fixing, and procuring enclosure systems and components for Kennedy Ground Controls Systems at launch pad B. (2) Organizational spreadsheets for all subsystems involved in the project. (Procurement, parts lists, drawings, purchase requests, etc) (3) Resolve is a project devoted to the lunar rover that will sample lunar soil in an effort to remove the moister and separate the metal from the oxygen to produce drinkable water. I helped with the humidity environmental generator for the experiment (moister detector).

  20. A SETI experiment

    NASA Astrophysics Data System (ADS)

    McLaughlin, W. I.

    1986-07-01

    In order to increase the probability of contact in the search for extraterrestrial intelligence (SETI), it has been proposed to search more intensively in certain regions of the electromagnetic spectrum ('the water hole'). The present paper describes a similar narrowing of the search in the time domain. Application of this strategy results in the SETI experiments searching for signals from the Tau Ceti system late in 1986 and early in 1987, and from the Epsilon Eridani system in mid 1988.

  1. Localized wave pulse experiments

    SciTech Connect

    Chambers, D L; Henderson, T L; Krueger, K L; Lewis, D K; Zilkowski, R N

    1999-06-01

    The Localized Wave project of the Strategic System Support Program has recently finished an experiment in cooperation with the Advanced SONAR group of the Applied Research Laboratory of the University of Texas at Austin. The purpose of the experiment was three-fold. They wanted to see if (1) the LW pulse could propagate over significant distances, to see if (2) a new type of array and drive system specifically designed for the pulse would increase efficiency over single frequency tone bursts, and to see if (3) the complexity of our 24 channel drivers resulted in better efficiency than a single equivalent pulse driving a piston. In the experiment, several LW pulses were launched from the Lake Travis facility and propagated over distances of either 100 feet or 600 feet, through a thermocline for the 600 foot measurements. The results show conclusively that the Localized Wave will propagate past the near field distance. The LW pulses resulted in extremely broad frequency band width pulses with narrow spatial beam patterns and unmeasurable side lobes. Their array gain was better than most tone bursts and further, were better than their equivalent piston pulses. This marks the first test of several Low Diffraction beams against their equivalent piston pulses, as well as the first propagation of LW pulses over appreciable distances. The LW pulse is now proven a useful tool in open water, rather than a laboratory curiosity. The experimental system and array were built by ARL, and the experiments were conducted by ARL staff on their standard test range. The 600 feet measurements were made at the farthest extent of that range.

  2. Holodeck-ISS Experience

    NASA Technical Reports Server (NTRS)

    Rainbolt, Phillip

    2016-01-01

    For the duration of my internship here at JSC for the summer 2016 session, the main project that I worked on dealt with hybrid reality simulations of the ISS. As an ER6 intern for the spacecraft software division, the main project that I worked alongside others was with regards to the Holodeck Virtual Reality Project, specifically with the ISS experience, with the use of the HTC Vive and controllers.

  3. Alloy undercooling experiments

    NASA Technical Reports Server (NTRS)

    Flemings, Merton C.; Matson, Douglas M.

    1995-01-01

    The research accomplished during 1995 can be organized into three parts. The first task involves analyzing the results of microgravity experiments carried out using TEMPUS hardware during the IML-2 mission on STS-65. The second part was to finalize ground-based experimentation which supported the above flight sample analysis. The final part was to provide technical support for post-flight mission activities specifically aimed at improving TEMPUS performance for potential future missions.

  4. Experiments in Developing Wakes

    DTIC Science & Technology

    2014-04-27

    experiments allowed for an interesting investigation as to the effects of finite space averaging techniques, and mimicking PIV sampling conditions in a...fluid. (2) To use this technique to investigate one example of an early wake with new analysis methods. (3) To compare results with numerical...technical objectives are twofold: (i) To investigate the flow field at early times so as to find when turbulent motions are affected by stratification

  5. The Blowgun Demonstration Experiment

    ERIC Educational Resources Information Center

    Tsukamoto, Koji; Uchino, Masanori

    2008-01-01

    We have found that a simple demonstration experiment using a match or a cotton swab and a drinking straw or an acrylic pipe serves as an effective introduction to dynamics. The most basic apparatus has a cotton swab serving as a dart and the straw as the blowgun. When blown from a starting point near the exit end of the straw, the cotton swab does…

  6. Delivering ideal employee experiences.

    PubMed

    Weiss, Marjorie D; Tyink, Steve; Kubiak, Curt

    2009-05-01

    Employee-centric strategies have moved from employee satisfaction and brand awareness to employee "affinity" or "attachment." In today's marketplace, occupational health nurses understand that differentiation (i.e., the perception of uniqueness) is the direct result of superior employee interactions, which lead to better employee care, enduring employee relationships, loyal employees, and satisfied employers. What drives employees to occupational health nurse attachment? The answer is a passion for rising above the competition to create ideal employee experiences.

  7. [GIST: our experience].

    PubMed

    Rossi, M T; Fasano, G; Morlino, A; Scutari, F

    2009-01-01

    Gastrointestinal stromal tumors (GIST) are generally found in the stomach or small intestine and less commonly in the colon and rectum. Complete surgical remove remains the best current therapy. In the treatment of advanced/metastatic GIST is available imatinib, a selective tyrosine kinase inhibitor. In our experience, 12 patients observed between 2000 and 2007 and affected by GIST underwent surgery, in one case associated to treatment with imatinib.

  8. The CKM Experiment

    SciTech Connect

    Hogan H. Nguyen

    2002-10-25

    I describe the CKM experiment, a new initiative using the Fermilab Main Injector to obtain {approx} 100 events of the ultra-rare decay mode K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}. The branching ratio will be used to extract |V*{sub ts}V{sub td}|. Due to the decay mode's theoretical cleanliness, it plays a key role in over-constraining the Standard Model description of CP violation.

  9. Analysis of Factorial Experiments.

    DTIC Science & Technology

    1985-09-01

    The pro- bability that y 13 is bad is .37. Choosing Q greater than .37 ends the iteration. Choos - ing Q so that Y 13 is identified as a bad...ances as a Fraction of Their Total. Annals of Eugenics , 11, 47-52. Cochran, W. G. and Cox, G. M. (1957) Experimental Designs. New York: John Wiley...Experiments. London: Oliver and Boyd. Finney, D. J. (1945) The Fractional Replication of Factorial Arrangements. Annals of Eugenics , 12, 291-301

  10. The LUX experiment

    DOE PAGES

    Akerib, D. S.; Araújo, H. M.; Bai, X.; ...

    2015-03-24

    We present the status and prospects of the LUX experiment, which employs approximately 300 kg of two-phase xenon to search for WIMP dark matter interactions. The LUX detector was commissioned at the surface laboratory of the Sanford Underground Research Facility in Lead, SD, between December 2011 and February 2012 and the detector has been operating underground since January, 2013. These proceedings review the results of the commissioning run as well as the status of underground data-taking.

  11. Experiences with groundwater contamination

    SciTech Connect

    Not Available

    1984-01-01

    This book discusses developments in combating groundwater contamination. The papers include: Regulation of Groundwater; Utility Experiences Related to Existing and Proposed Drinking Water Regulations; Point-of-Use Treatment Technology to Control Organic and Inorganic Contamination; Hazardous Waste Disposal Practices and Groundwater Contamination; Reverse Osmosis Treatment to Control Inorganic and Volatile Organic Contamination; The Dilemma of New Wells Versus Treatment; Characteristics and Handling of Wastes From Groundwater Treatment Systems; and Removing Solvents to Restore Drinking Water at Darien, Connecticut.

  12. The MUNU experiment

    NASA Astrophysics Data System (ADS)

    Broggini, C.

    1998-07-01

    We built a low background detector based on a 1 m3 time projection chamber surrounded by an active anti-Compton shielding. The detector has been installed near a nuclear reactor in Bugey for the experimental study of the overlineνee - scattering. A low threshold, around 500 keV, can be set on the electron recoil energy, giving the experiment a sensitivity to the overlineνe magnetic moment down to 3·10 -11 Bohr magnetons.

  13. The MUNU experiment

    NASA Astrophysics Data System (ADS)

    Broggini, C.; MUNU Collaboration

    1994-05-01

    We intend to build a low background detector based on a gas TPC to be installed near a nuclear reactor in Bugey for the experimental study of overlineνee - scattering. The threshold on the electron recoil energy can be set very low, around 500 keV, giving the experiment a good sensitivity to the magnetic moment of the overlineνe, extending down to 2-3.10 -11 Bohr magnetons.

  14. NPB Cesium Space Experiment

    NASA Technical Reports Server (NTRS)

    Parsons, George M., III

    1992-01-01

    Neutral Particle Beam (NPB) weapons systems are planned to perform the ballistic missile defense functions of nuclear weapon/decoy discrimination and warhead kill at appropriate energy levels and ion currents. Negatively charged ions are produced in a specialized ion source and focused into a high quality particle beam. NPB linear accelerators accelerate and steer the negatively charged ions using electric and magnetic fields. After acceleration and steering the neutralizer system strips away extra electrons from ions to form the electrically neutral particle beam. The neutral beam then travels through space to the target unaffected by the Earth's magnetic fields. Continuing technological advances have greatly reduced the size and weight of NPB accelerator systems. Ion current production has been enhanced by over 100 percent with the intermittent addition of cesium at the NPB ion source device. This increase in current is essential to attain the most light weight, compact NPB platforms and minimize expensive launch costs. Addition of cesium into the ion source has been identified by the NPB community as the highest priority risk reduction space experiment necessary prior to planned NPB accelerator experiments and later weapons systems. The NPB Cesium Space Experiment is planned to successfully demonstrate controlled cesium introduction and vaporization into a simulated ion source chamber. Microgravity effects on the cesium deposition will be studied as will the effects of small amounts of cesium on high voltage accelerator components that might be susceptible to electrical insulator break downs. The experiment design will simulate as closely as possible the environment, physical and operational characteristics of the actual NPB ion source.

  15. The CONNIE experiment

    NASA Astrophysics Data System (ADS)

    Aguilar-Arevalo, A.; Bertou, X.; Bonifazi, C.; Butner, M.; Cancelo, G.; Castaneda Vazquez, A.; Cervantes Vergara, B.; Chavez, C. R.; Da Motta, H.; D'Olivo, J. C.; Dos Anjos, J.; Estrada, J.; Fernandez Moroni, G.; Ford, R.; Foguel, A.; Hernandez Torres, K. P.; Izraelevitch, F.; Kavner, A.; Kilminster, B.; Kuk, K.; Lima, H. P., Jr.; Makler, M.; Molina, J.; Moreno-Granados, G.; Moro, J. M.; Paolini, E. E.; Sofo Haro, M.; Tiffenberg, J.; Trillaud, F.; Wagner, S.

    2016-10-01

    The CONNIE experiment uses fully depleted, high resistivity CCDs as particle detectors in an attempt to measure for the first time the Coherent Neutrino-Nucleus Elastic Scattering of antineutrinos from a nuclear reactor with silicon nuclei. This talk, given at the XV Mexican Workshop on Particles and Fields (MWPF), discussed the potential of CONNIE to perform this measurement, the installation progress at the Angra dos Reis nuclear power plant, as well as the plans for future upgrades.

  16. Detonation Shock Radius Experiments.

    NASA Astrophysics Data System (ADS)

    Lambert, David; Debes, Joshua; Stewart, Scott; Yoo, Sunhee

    2007-06-01

    A previous passover experiment [1] was designed to create a complex detonation transient used in validating a reduced, asymptotically derived description of detonation shock dynamics (DSD). An underlying question remained on determining the location of the initial detonation shock radius to start the DSD simulation with respect to the dynamical response of the initiation system coupling's to the main charge. This paper concentrates on determining the initial shock radius required of such DSD governed problems. `Cut-back' experiments of PBX-9501 were conducted using an initiation system that sought to optimize the transferred detonation to the desired constant radius, hemispherical shape. Streak camera techniques captured the breakout on three of the prism's surfaces for time-of-arrival data. The paper includes comparisons to simulations using constant volume explosion and high pressure hot spots. The results of the experiments and simulation efforts provide fundamental design considerations for actual explosive systems and verify necessary conditions from which the asymptotic theory of DSD may apply. [1] Lambert, D., Stewart, D. Scott and Yoo, S. and Wescott, B., ``Experimental Validation of Detonation Shock Dynamics in Condensed Explosives. J. of Fluid Mechs., Vol. 546, pp.227-253 (2006).

  17. Long Baseline Neutrino Experiments

    NASA Astrophysics Data System (ADS)

    Mezzetto, Mauro

    2016-05-01

    Following the discovery of neutrino oscillations by the Super-Kamiokande collaboration, recently awarded with the Nobel Prize, two generations of long baseline experiments had been setup to further study neutrino oscillations. The first generation experiments, K2K in Japan, Minos in the States and Opera in Europe, focused in confirming the Super-Kamiokande result, improving the precision with which oscillation parameters had been measured and demonstrating the ντ appearance process. Second generation experiments, T2K in Japan and very recently NOνA in the States, went further, being optimized to look for genuine three neutrino phenomena like non-zero values of θ13 and first glimpses to leptonic CP violation (LCPV) and neutrino mass ordering (NMO). The discovery of leptonic CP violation will require third generation setups, at the moment two strong proposals are ongoing, Dune in the States and Hyper-Kamiokande in Japan. This review will focus a little more in these future initiatives.

  18. The QUIJOTE experiment

    NASA Astrophysics Data System (ADS)

    López-Caniego, Marcos

    2015-08-01

    The QUIJOTE (Q-U-I JOint Tenerife) CMB Experiment is observing the polarization of the Cosmic Microwave Background and other Galactic and extragalactic signals at medium and large angular scales in the frequency range of 10-40 GHz. This experiment will provide valuable information about the polarization properties of synchrotron and anomalous microwave emission at these frequencies. The maps obtained with the multi-frequency instrument (10-20 GHz), in combination with data from other experiments like Planck and the VLA, will be used to clean the diffuse and compact foreground emission at 30 and 40 GHz, the cosmological channels. After three years of effective observations we expect to reach the required sensitivity to detect a primordial gravitational-wave component if the tensor-to-scalar ratio is larger than r = 0.05. At the moment we have completed the Wide Survey with the multi-frequency instrument, covering 20.000 square degrees of the Northern hemisphere. In addition, we have deep integrations of our main calibrators Taurus A, Cassiopea A, Jupiter and of the Perseus molecular complex region, where we have measured the spectrum of the anomalous microwave emission. We also have observed several regions of interest for our science program where we plan to study the compact and diffuse polarized emission.

  19. Mars brine formation experiment

    NASA Technical Reports Server (NTRS)

    Moore, Jeffrey M.; Bullock, Mark A.; Stoker, Carol R.

    1992-01-01

    Evaporites, particularly carbonates, nitrates, and sulfates, may be major sinks of volatiles scavenged from the martian atmosphere. Mars is thought to have once had a denser, warmer atmosphere that permitted the presence of liquid surface water. The conversion of atmospheric CO2 into carbonate is hypothesized to have degraded the martian climate to its present state of a generally subfreezing, desiccated desert. The rate for such a conversion under martian conditions is poorly known, so the time scale of climate degradation by this process cannot be easily evaluated. If some models are correct, carbonate formation may have been fast at geological time scales. The experiments of Booth and Kieffer also imply fast (10(exp 6) - 10(exp 7) yr) removal of the missing CO2 inventory, estimated to be 1 - 5 bar, by means of carbonate formation. The timing of formation of many of the fluvial features observed on Mars is, in large part, dependent on when and how fast the atmosphere changed. A knowledge of the rate at which carbonates and nitrates formed is also essential for assessing the probability that life, or its chemical precursors, could have developed on Mars. No previous experiments have quantitatively evaluated the rate of solution for a suite of mobile anions and cations from unaltered minerals and atmospheric gases into liquid water under Mars-like conditions. Such experiments are the focus of this task.

  20. ACTS broadband aeronautical experiment

    NASA Technical Reports Server (NTRS)

    Abbe, Brian S.; Jedrey, Thomas C.; Estabrook, Polly; Agan, Martin J.

    1993-01-01

    In the last decade, the demand for reliable data, voice, and video satellite communication links between aircraft and ground to improve air traffic control, airline management, and to meet the growing demand for passenger communications has increased significantly. It is expected that in the near future, the spectrum required for aeronautical communication services will grow significantly beyond that currently available at L-band. In anticipation of this, JPL is developing an experimental broadband aeronautical satellite communications system that will utilize NASA's Advanced Communications Technology Satellite (ACTS) as a satellite of opportunity and the technology developed under JPL's ACTS Mobile Terminal (AMT) Task to evaluate the feasibility of using K/Ka-band for these applications. The application of K/Ka-band for aeronautical satellite communications at cruise altitudes is particularly promising for several reasons: (1) the minimal amount of signal attenuation due to rain; (2) the reduced drag due to the smaller K/Ka-band antennas (as compared to the current L-band systems); and (3) the large amount of available bandwidth. The increased bandwidth available at these frequencies is expected to lead to significantly improved passenger communications - including full-duplex compressed video and multiple channel voice. A description of the proposed broadband experimental system will be presented including: (1) applications of K/Ka-band aeronautical satellite technology to U.S. industry; (2) the experiment objectives; (3) the experiment set-up; (4) experimental equipment description; and (5) industrial participation in the experiment and the benefits.

  1. The Kauai Experiment

    NASA Astrophysics Data System (ADS)

    Porter, Michael B.; Hursky, Paul; Siderius, Martin; Badiey, Mohsen; Caruthers, Jerald; Hodgkiss, William S.; Raghukumar, Kaustubha; Rouseff, Daniel; Fox, Warren; de Moustier, Christian; Calder, Brian; Kraft, Barbara J.; McDonald, Keyko; Stein, Peter; Lewis, James K.; Rajan, Subramaniam

    2004-11-01

    The Kauai Experiment was conducted from June 24 to July 9, 2003 to provide a comprehensive study of acoustic propagation in the 8-50 kHz band for diverse applications. Particular sub-projects were incorporated in the overall experiment 1) to study the basic propagation physics of forward-scattered high-frequency (HF) signals including time/angle variability, 2) to relate environmental conditions to underwater acoustic modem performance including a variety of modulation schemes such as MFSK, DSSS, QAM, passive-phase conjugation, 3) to demonstrate HF acoustic tomography using Pacific Missile Range Facility assets and show the value of assimilating tomographic data in an ocean circulation model, and 4) to examine the possibility of improving multibeam accuracy using tomographic data. To achieve these goals, extensive environmental and acoustic measurements were made yielding over 2 terabytes of data showing both the short scale (seconds) and long scale (diurnal) variations. Interestingly, the area turned out to be extremely active with a large mixed layer overlying a very dynamic lower channel. This talk will present an overview of the experiment and preliminary results.

  2. ATD-2 HITL Experiment Overview

    NASA Technical Reports Server (NTRS)

    Verma, Savita

    2016-01-01

    ATD-2 HITL plans and how experiments are planned or created will be discussed here. The previous HITLs- TSTR, CEED and upcoming HITLs will be described here. The full experiment plan including methodology, data collection and such will be described to help the KARI folks design their own experiments and get a flavor for how experiments are designed and conducted.

  3. AGS Experiments: 1989, 1990, 1991

    SciTech Connect

    Depken, J.C.

    1992-02-01

    This report contains: Experimental areas layout; table of beam parameters and fluxes; experiment schedule as run''; proposed 1992 schedule; a listing of experiments by number; two-page summaries of each experiment begin here, also ordered by number; publications of AGS Experiments begin here; and list of AGS Experimenters begins here.

  4. AGS Experiments: 1989, 1990, 1991

    SciTech Connect

    Depken, J.C.

    1992-02-01

    This report contains: Experimental areas layout; table of beam parameters and fluxes; experiment schedule ``as run``; proposed 1992 schedule; a listing of experiments by number; two-page summaries of each experiment begin here, also ordered by number; publications of AGS Experiments begin here; and list of AGS Experimenters begins here.

  5. Aesthetic Experience and Aesthetic Analysis

    ERIC Educational Resources Information Center

    Fenner, David E. W.

    2003-01-01

    The "raw data" that aesthetics is meant to explain is the aesthetic experience. People have experiences that they class off from other experiences and label, as a class, the aesthetic ones. Aesthetic experience is basic, and all other things aesthetic--aesthetic properties, aesthetic objects, aesthetic attitudes--are secondary in their importance…

  6. Situating emotional experience

    PubMed Central

    Wilson-Mendenhall, Christine D.; Barrett, Lisa Feldman; Barsalou, Lawrence W.

    2013-01-01

    Psychological construction approaches to emotion suggest that emotional experience is situated and dynamic. Fear, for example, is typically studied in a physical danger context (e.g., threatening snake), but in the real world, it often occurs in social contexts, especially those involving social evaluation (e.g., public speaking). Understanding situated emotional experience is critical because adaptive responding is guided by situational context (e.g., inferring the intention of another in a social evaluation situation vs. monitoring the environment in a physical danger situation). In an fMRI study, we assessed situated emotional experience using a newly developed paradigm in which participants vividly imagine different scenarios from a first-person perspective, in this case scenarios involving either social evaluation or physical danger. We hypothesized that distributed neural patterns would underlie immersion in social evaluation and physical danger situations, with shared activity patterns across both situations in multiple sensory modalities and in circuitry involved in integrating salient sensory information, and with unique activity patterns for each situation type in coordinated large-scale networks that reflect situated responding. More specifically, we predicted that networks underlying the social inference and mentalizing involved in responding to a social threat (in regions that make up the “default mode” network) would be reliably more active during social evaluation situations. In contrast, networks underlying the visuospatial attention and action planning involved in responding to a physical threat would be reliably more active during physical danger situations. The results supported these hypotheses. In line with emerging psychological construction approaches, the findings suggest that coordinated brain networks offer a systematic way to interpret the distributed patterns that underlie the diverse situational contexts characterizing emotional

  7. Southeast Regional Experiment Station

    NASA Astrophysics Data System (ADS)

    1994-08-01

    This is the final report of the Southeast Regional Experiment Station project. The Florida Solar Energy Center (FSEC), a research institute of the University of Central Florida (UCF), has operated the Southeast Regional Experiment Station (SE RES) for the US Department of Energy (DOE) since September 1982. Sandia National Laboratories, Albuquerque (SNLA) provides technical program direction for both the SE RES and the Southwest Regional Experiment Station (SW RES) located at the Southwest Technology Development Institute at Las Cruces, New Mexico. This cooperative effort serves a critical role in the national photovoltaic program by conducting system evaluations, design assistance and technology transfer to enhance the cost-effective utilization and development of photovoltaic technology. Initially, the research focus of the SE RES program centered on utility-connected PV systems and associated issues. In 1987, the SE RES began evaluating amorphous silicon (a-Si) thin-film PV modules for application in utility-interactive systems. Stand-alone PV systems began receiving increased emphasis at the SE RES in 1986. Research projects were initiated that involved evaluation of vaccine refrigeration, water pumping and other stand-alone power systems. The results of this work have led to design optimization techniques and procedures for the sizing and modeling of PV water pumping systems. Later recent research at the SE RES included test and evaluation of batteries and charge controllers for stand-alone PV system applications. The SE RES project provided the foundation on which FSEC achieved national recognition for its expertise in PV systems research and related technology transfer programs. These synergistic products of the SE RES illustrate the high visibility and contributions the FSEC PV program offers to the DOE.

  8. Experience the Moon

    NASA Astrophysics Data System (ADS)

    Ortiz-Gil, A.; Benacchio, L.; Boccato, C.

    2011-10-01

    The Moon is, together with the Sun, the very first astronomical object that we experience in our life. As this is an exclusively visual experience, people with visual impairments need a different mode to experience it too. This statement is especially true when events, such as more and more frequent public observations of sky, take place. This is the reason why we are preparing a special package for visual impaired people containing three brand new items: 1. a tactile 3D Moon sphere in Braille with its paper key in Braille. To produce it we used imaging data obtained by NASA's mission Clementine, along with free image processing and 3D rendering software. In order to build the 3D small scale model funding by Europlanet and the Italian Ministry for Research have been used. 2. a multilingual web site for visually impaired users of all ages, on basic astronomy together with an indepth box about the Moon; 3. a book in Braille with the same content of the Web site mentioned above. All the items will be developed with the collaboration of visually impaired people that will check each step of the project and support their comments and criticism to improve it. We are going to test this package during the next International Observe the Moon Night event. After a first testing phase we'll collect all the feedback data in order to give an effective form to the package. Finally the Moon package could be delivered to all those who will demand it for outreach or educational goals.

  9. Initial blood storage experiment

    NASA Technical Reports Server (NTRS)

    Surgenor, Douglas MACN.

    1988-01-01

    The design of the Initial Blood Storage Experiment (IBSE) was based upon a carefully controlled comparison between identical sets of human blood cell suspensions - red cells, white cell, and platelets - one set of which was transported aboard the Columbia on a 6 day 11 hour mission, and the other held on the ground. Both sets were carried inside stainless steel dewars within specially fabricated flight hardware. Individual bags of cell suspensions were randomly assigned with respect to ground vs orbit status, dewar chamber, and specific location within the dewar. To foster optimal preservation, each cell type was held under specific optimal conditions of pH, ionic strength, solute concentration, gas tension, and temperature. An added variable in this initial experiment was provided by the use of three different polymer/plasticizer formulations for the sealed bags which held the blood cells. At termination of the experiment, aliquots of the suspensions, identified only by code, were distributed to be assayed. Assays were selected to constitute a broad survey of cellular properties and thereby maximize the chances of detection of gravitational effects. A total of 74 different outcome measurements were reported for statistical analysis. When the measurements were completed, the results were entered into the IBSE data base, at which time the data were matched with the original blood bag numbers to determine their status with respect to polymer/plasticizer type, orbit status (orbit or ground), and storage position within the experimental hardware. The data were studied by analysis of variance. Initially, type of bag and orbital status were main factors; later more detailed analyses were made on specific issues such as position in the hardware and specific plastic. If the analysis of variance indicated a statistical significance at the 5 percent level the corresponding p-value was reported.

  10. The European experience.

    PubMed

    Roels, Leo; Rahmel, Axel

    2011-04-01

    This mini-review on European experiences with tackling the problem of organ shortage for transplantation was based on a literature review of predominantly European publications dealing with the issue of organ donation from deceased donors. The authors tried to identify the most significant factors that have demonstrated to impact on donation rates from deceased donors and subsequent transplant successes. These factors include legislative measures (national laws and European Directives), optimization of the donation process, use of expanded criteria donors, innovative preservation and surgical techniques, organizational efforts, and improved allocation algorithms.

  11. Initial blood storage experiment

    NASA Technical Reports Server (NTRS)

    Surgenor, Douglas MACN.

    1988-01-01

    The possibility of conducting experiments with the formed elements of the blood under conditions of microgravity opens up important opportunities to improve the understanding of basic formed element physiology, as well as, contribution to improved preservation of the formed elements for use in transfusion. The physiological, biochemical, and physical changes of the membrane of the erythrocyte, platelet, and leukocyte was studied during storage under two specific conditions: standard blood bank conditions and microgravity, utilizing three FDA approved plastic bags. Storage lesions; red cell storage on Earth; platelet storage on Earth; and leukocyte storage Earth were examined. The interaction of biomaterials and blood cells was studied during storage.

  12. The QUIJOTE CMB Experiment

    NASA Astrophysics Data System (ADS)

    Rubiño-Martín, J. A.; Rebolo, R.; Tucci, M.; Génova-Santos, R.; Hildebrandt, S. R.; Hoyland, R.; Herreros, J. M.; Gómez-Reñasco, F.; Caraballo, C. López; Martínez-González, E.; Vielva, P.; Herranz, D.; Casas, F. J.; Artal, E.; Aja, B.; Fuente, L. dela; Cano, J. L.; Villa, E.; Mediavilla, A.; Pascual, J. P.; Piccirillo, L.; Maffei, B.; Pisano, G.; Watson, R. A.; Davis, R.; Davies, R.; Battye, R.; Saunders, R.; Grainge, K.; Scott, P.; Hobson, M.; Lasenby, A.; Murga, G.; Gómez, C.; Gómez, A.; Ariño, J.; Sanquirce, R.; Pan, J.; Vizcargüenaga, A.; Etxeita, B.

    We present the current status of the QUIJOTE (Q-U-I JOint TEnerife) CMB Experiment, a new instrument which will start operations early in 2009 at Teide Observatory with the aim of characterizing the polarization of the CMB and other processes of galactic and extragalactic emission in the frequency range 10-30GHz and at large angular scales. QUIJOTE will be a valuable complement at low frequencies for the PLANCK mission, and will have the required sensitivity to detect a primordial gravitational-wave component if the tensor-to-scalar ratio is larger than r = 0.05.

  13. NASA's supercomputing experience

    NASA Technical Reports Server (NTRS)

    Bailey, F. Ron

    1990-01-01

    A brief overview of NASA's recent experience in supercomputing is presented from two perspectives: early systems development and advanced supercomputing applications. NASA's role in supercomputing systems development is illustrated by discussion of activities carried out by the Numerical Aerodynamical Simulation Program. Current capabilities in advanced technology applications are illustrated with examples in turbulence physics, aerodynamics, aerothermodynamics, chemistry, and structural mechanics. Capabilities in science applications are illustrated by examples in astrophysics and atmospheric modeling. Future directions and NASA's new High Performance Computing Program are briefly discussed.

  14. Results of railgun experiments

    SciTech Connect

    Hawke, R.S.; Brooks, A.L.; Fowler, C.M.; Peterson, D.R.

    1983-04-01

    During the 1979 Megagauss II conference the hypervelocity potential of railguns and the pulsed power technology needed to power them were discussed. Since then, many laboratories have initiated railgun R and D projects for a variety of potential applications. Los Alamos and Lawrence Livermore National Laboratories initiated a collaborative experimental railgun project which resulted in several successes in accelerating projectiles to high velocities, emphasized the limits on railgun operation, and indicated that the numerical modeling of railgun operation was in good agreement with the experiments.

  15. Rotational fluid flow experiment

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This project which began in 1986 as part of the Worcester Polytechnic Institute (WPI) Advanced Space Design Program focuses on the design and implementation of an electromechanical system for studying vortex behavior in a microgravity environment. Most of the existing equipment was revised and redesigned by this project team, as necessary. Emphasis was placed on documentation and integration of the electrical and mechanical subsystems. Project results include reconfiguration and thorough testing of all hardware subsystems, implementation of an infrared gas entrainment detector, new signal processing circuitry for the ultrasonic fluid circulation device, improved prototype interface circuits, and software for overall control of experiment operation.

  16. Geophysical fluid flow experiment

    NASA Technical Reports Server (NTRS)

    Broome, B. G.; Fichtl, G.; Fowlis, W.

    1979-01-01

    The essential fluid flow processes associated with the solar and Jovian atmospheres will be examined in a laboratory experiment scheduled for performance on Spacelab Missions One and Three. The experimental instrumentation required to generate and to record convective fluid flow is described. Details of the optical system configuration, the lens design, and the optical coatings are described. Measurement of thermal gradient fields by schlieren techniques and measurement of fluid flow velocity fields by photochromic dye tracers is achieved with a common optical system which utilizes photographic film for data recording. Generation of the photochromic dye tracers is described, and data annotation of experimental parameters on the film record is discussed.

  17. Active seismic experiment

    NASA Technical Reports Server (NTRS)

    Kovach, R. L.; Watkins, J. S.; Talwani, P.

    1972-01-01

    The Apollo 16 active seismic experiment (ASE) was designed to generate and monitor seismic waves for the study of the lunar near-surface structure. Several seismic energy sources are used: an astronaut-activated thumper device, a mortar package that contains rocket-launched grenades, and the impulse produced by the lunar module ascent. Analysis of some seismic signals recorded by the ASE has provided data concerning the near-surface structure at the Descartes landing site. Two compressional seismic velocities have so far been recognized in the seismic data. The deployment of the ASE is described, and the significant results obtained are discussed.

  18. Magnetohydrodynamic Augmented Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Cole, John; Lineberry, John; Chapman, Jim; Schmidt, Harold; Cook, Stephen (Technical Monitor)

    2002-01-01

    A fundamental obstacle to routine space access is the specific energy limitations associated with chemical fuels. In the case of vertical take-off, the high thrust needed for vertical liftoff and acceleration to orbit translates into power levels in the 10 GW range. Furthermore, useful payload mass fractions are possible only if the exhaust particle energy (i.e., exhaust velocity) is much greater than that available with traditional chemical propulsion. The electronic binding energy released by the best chemical reactions (e.g., LOX/LH2 for example, is less than 2 eV per product molecule (approx. 1.8 eV per H2O molecule), which translates into particle velocities less than 5 km/s. Useful payload fractions, however, will require exhaust velocities exceeding 15 km/s (i.e., particle energies greater than 20 eV). As an added challenge, the envisioned hypothetical RLV (reusable launch vehicle) should accomplish these amazing performance feats while providing relatively low acceleration levels to orbit (2-3g maximum). From such fundamental considerations, it is painfully obvious that planned and current RLV solutions based on chemical fuels alone represent only a temporary solution and can only result in minor gains, at best. What is truly needed is a revolutionary approach that will dramatically reduce the amount of fuel and size of the launch vehicle. This implies the need for new compact high-power energy sources as well as advanced accelerator technologies for increasing engine exhaust velocity. Electromagnetic acceleration techniques are of immense interest since they can be used to circumvent the thermal limits associated with conventional propulsion systems. This paper describes the Magnetohydrodynamic Augmented Propulsion Experiment (MAPX) being undertaken at NASA Marshall Space Flight Center (MSFC). In this experiment, a 1-MW arc heater is being used as a feeder for a 1-MW magnetohydrodynamic (MHD) accelerator. The purpose of the experiment is to demonstrate

  19. Experience with the CAIS

    NASA Technical Reports Server (NTRS)

    Tighe, Michael F.

    1986-01-01

    Intermetrics' experience is that the Ada package construct, which allows separation of specification and implementation allows specification of a CAIS that is transportable across varying hardware and software bases. Additionally, the CAIS is an excellent basis for providing operating system functionality to Ada applications. By allowing the Byron APSE to be moved easily from system to system, and allowing significant re-writes of underlying code. Ada and the CAIS provide portability as well as transparency to change at the application operating system interface level.

  20. Integrated Immune Experiment

    NASA Technical Reports Server (NTRS)

    Crucian, Brian

    2009-01-01

    This viewgraph presentation reviews NASA's Integrated Immune Experiment. The objectives include: 1) Address significant lack of data regarding immune status during flight; 2) Replace several recent immune studies with one comprehensive study that will include in-flight sampling; 3) Determine the in-flight status of immunity, physiological stress, viral immunity/reactivation; 4) Determine the clinical risk related to immune dysregulation for exploration class spaceflight; and 5) Determine the appropriate monitoring strategy for spaceflight-associated immune dysfunction, that could be used for the evaluation of countermeasures.

  1. Microlinear piezo drive experiments

    NASA Astrophysics Data System (ADS)

    Azin, A. V.; Bogdanov, E. P.; Rikkonen, S. V.; Ponomarev, S. V.; Khramtsov, A. M.

    2017-02-01

    The article embraces the experimental description of the micro linear piezo drive intended for the peripheral cord tensioner in the reflecting surface shape regulator system for large-sized transformable spacecraft antenna reflectors. The research target is the experimental investigation of the micro linear piezo drive to determine the stable oscillatory system operating modes which would include improved energy conversion parameters. The following points are briefly presented: test stand construction-design of the peripheral cord tensioner; the determined frequency characteristics and the identified resonant and actual frequencies of an oscillatory system under inertia load. A series of experiments has been conducted for both different preliminary voltages and inertia mass values.

  2. Fundamental experiments in velocimetry

    SciTech Connect

    Briggs, Matthew Ellsworth; Hull, Larry; Shinas, Michael

    2009-01-01

    One can understand what velocimetry does and does not measure by understanding a few fundamental experiments. Photon Doppler Velocimetry (PDV) is an interferometer that will produce fringe shifts when the length of one of the legs changes, so we might expect the fringes to change whenever the distance from the probe to the target changes. However, by making PDV measurements of tilted moving surfaces, we have shown that fringe shifts from diffuse surfaces are actually measured only from the changes caused by the component of velocity along the beam. This is an important simplification in the interpretation of PDV results, arising because surface roughness randomizes the scattered phases.

  3. Experiences with solar power

    NASA Astrophysics Data System (ADS)

    Kesselring, P.

    1985-11-01

    Experience with solar thermal plants is reviewed. The component and subsystems development of the last decade and particularly the receiver, collector and heliostat field development is a technical success. Solar specific problems on the system and component level arose, when off the shelf solutions of fossile fired plants were transferred uncritically. It is shown that concentrated solar radiation is a relatively cheap high quality fuel. Other uses than electricity generation are high temperature processes and the production of solar fuels and chemicals. A technical and economic comparison of solar thermal and photovoltaic electricity generation is made.

  4. Transpiration Cooling Experiment

    NASA Technical Reports Server (NTRS)

    Song, Kyo D.; Ries, Heidi R.; Scotti, Stephen J.; Choi, Sang H.

    1997-01-01

    The transpiration cooling method was considered for a scram-jet engine to accommodate thermally the situation where a very high heat flux (200 Btu/sq. ft sec) from hydrogen fuel combustion process is imposed to the engine walls. In a scram-jet engine, a small portion of hydrogen fuel passes through the porous walls of the engine combustor to cool the engine walls and at the same time the rest passes along combustion chamber walls and is preheated. Such a regenerative system promises simultaneously cooling of engine combustor and preheating the cryogenic fuel. In the experiment, an optical heating method was used to provide a heat flux of 200 Btu/sq. ft sec to the cylindrical surface of a porous stainless steel specimen which carried helium gas. The cooling efficiencies by transpiration were studied for specimens with various porosity. The experiments of various test specimens under high heat flux have revealed a phenomenon that chokes the medium flow when passing through a porous structure. This research includes the analysis of the system and a scaling conversion study that interprets the results from helium into the case when hydrogen medium is used.

  5. PHOBOS experiment at RHIC

    SciTech Connect

    Wozniak, K.; PHOBOS Collaboration

    1995-12-01

    The study of relativistic heavy nuclei collisions at RHIC opens a new area of physics--the physics of hadronic matter at very high energy densities. The conditions necessary to create a new state of matter, never before seen in the laboratory, may be reached. It gives a chance to study the quantum chromodynamics predictions of the phase transition from hadronic matter to a quark-gluon plasma. The PHOBOS experiment will investigate almost all predicted signals of the QGP formation. General event properties (angular distribution of charged particles, total multiplicity) will be combined with detailed information on particles emitted in the central rapidity region (particle ratios {pi}/K/p, p{sub t} spectra, correlations, {phi} meson properties). Similar studies will be done also in the other three experiments at RHIC, but there are many important observables for which PHOBOS will provide unique information. The multiplicity detector covers almost a full phase space, recording all charged particles with pseudorapidities {vert_bar}{eta}{vert_bar} {le} 5.4. In the PHOBOS spectrometer particles emitted in the central rapidity region will be measured and identified starting from lowest transverse momenta (20 MeV/c for pions). The high rate unbiased trigger gives a chance to see unpredicted phenomena and enables the study of very rare processes that require large statistics. The measurements of the converting photons planned for some runs will be used to study the {pi}{sup 0}/({pi}{sup +} + {pi}{sup {minus}}) ratio in selected phase space intervals.

  6. 2169 Steel Waveform Experiments

    NASA Astrophysics Data System (ADS)

    Furnish, M.; Alexander, C.; Reinhart, W.; Brown, J.

    2013-06-01

    In support of efforts to develop multiscale models of materials, we performed eight gas gun impact experiments on 2169 steel (21% Cr, 6% Ni, 9% Mn). These experiments provided shock, reshock and release velocimetry data, with initial shock stresses ranging from 10 to 50 GPa (particle velocities from 0.25 to 1.05 km/s). Both windowed and free-surface measurements were used, with samples 1 to 5 mm thick. The study focused on dynamic strength determination via the release/reshock paths. Reshock tests with explosively welded impactors produced clean results. The free-surface samples, which were steps on a single piece of steel, showed lower wavespeeds for thin (1 mm) samples than for thicker (2 or 4 mm) samples. A configuration used for the last three shots allowed release information to be determined from these free surface samples as well. The sample strength appears to increase with stress from ~1 GPa to ~3 GPa over this range, consistent with other recent work but about 40% above the Steinberg model. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  7. Olympus propagation experiments

    NASA Technical Reports Server (NTRS)

    Arbesser-Rastburg, Bertram

    1994-01-01

    A summary of the activities of the OPEX (Olympus Propagation EXperimenters) group is given and some of the recent findings are presented. OLYMPUS, a telecommunication satellite owned by the European Space Agency, was launched on 12 June 1989. After the in-orbit tests were completed (in September 1989) the first propagation experiments started. Throughout 1990 the spacecraft functioned very well and a large number of experimenters received the beacon signals. On 29 May 1991 the spacecraft became inoperational after a major technical problem. With a series of complicated procedures OLYMPUS was recovered on 15 August 1991 - the first time in history that a civilian telecommunications satellite was brought back to service after losing power and telemetry. The propagation experiments were back on track. However, the recovery had used up so much fuel that the North-South station keeping had to be abandoned, which led to a natural increase of inclination at a rate of about 0.8 deg per year. On 10 October 1992 the second 30 GHz beacon tube failed, causing a loss of this beacon signal. The other two beacon frequencies continued to deliver a stable signal for more than two years. On 12 August 1993 the spacecraft experienced another problem with the altitude control, but this time there was not enough fuel left for a recovery maneuver and thus the mission came to an end.

  8. Experiments with Ξ- atoms

    NASA Astrophysics Data System (ADS)

    Batty, C. J.; Friedman, E.; Gal, A.

    1999-01-01

    Experiments with Ξ- atoms are proposed in order to study the nuclear interaction of Ξ hyperons. The production of Ξ- in the (K-,K+) reaction, the Ξ- stopping in matter, and its atomic cascade are incorporated within a realistic evaluation of the results expected for Ξ- x-ray spectra across the periodic table, using an assumed Ξ-nucleus optical potential Vopt. Several optimal targets for measuring the strong-interaction shift and width of the x-ray transition to the ``last'' atomic level observed are singled out: F, Cl, I, and Pb. The sensitivity of these observables to the parameters of Vopt is considered. The relevance of such experiments is discussed in the context of strangeness -2 nuclear physics and multistrange nuclear matter. Finally, with particular reference to searches for the H dibaryon, the properties of Ξ-d atoms are also discussed. The role of Stark mixing and its effect on S and P state capture of Ξ- by the deuteron together with estimates of the resulting probability for producing the H dibaryon are considered in detail.

  9. RACE AS LIVED EXPERIENCE

    PubMed Central

    Garcia, John A.; Sanchez, Gabriel R.; Sanchez-Youngman, Shannon; Vargas, Edward D.; Ybarra, Vickie D.

    2015-01-01

    A growing body of social science research has sought to conceptualize race as a multidimensional concept in which context, societal relations, and institutional dynamics are key components. Utilizing a specially designed survey, we develop and use multiple measures of race (skin color, ascribed race, and discrimination experiences) to capture race as “lived experience” and assess their impact on Latinos’ self-rated health status. We model these measures of race as a lived experience to test the explanatory power of race, both independently and as an integrated scale with categorical regression, scaling, and dimensional analyses. Our analyses show that our multiple measures of race have significant and negative effects on Latinos’ self-reported health. Skin color is a dominant factor that impacts self-reported health both directly and indirectly. We then advocate for the utilization of multiple measures of race, adding to those used in our analysis, and their application to other health and social outcomes. Our analysis provides important contributions across a wide range of health, illness, social, and political outcomes for communities of color. PMID:26681972

  10. The Halogen Occultation Experiment

    NASA Technical Reports Server (NTRS)

    Russell, James M., III; Gordley, Larry L.; Park, Jae H.; Drayson, S. R.; Hesketh, W. D.; Cicerone, Ralph J.; Tuck, Adrian F.; Frederick, John E.; Harries, John E.; Crutzen, Paul J.

    1993-01-01

    The Halogen Occultation Experiment (HALOE) uses solar occultation to measure vertical profiles of O3, HCl, HF, CH4, H2O, NO, NO2, aerosol extinction, and temperature versus pressure with an instantaneous vertical field of view of 1.6 km at the earth limb. Latitudinal coverage is from 80 deg S to 80 deg N over the course of 1 year and includes extensive observations of the Antarctic region during spring. The altitude range of the measurements extends from about 15 km to about 60-130 km, depending on channel. Experiment operations have been essentially flawless, and all performance criteria either meet or exceed specifications. Internal data consistency checks, comparisons with correlative measurements, and qualitative comparisons with 1985 atmospheric trace molecule spectroscopy (ATMOS) results are in good agreement. Examples of pressure versus latitude cross sections and a global orthographic projection for the September 21 to October 15, 1992, period show the utility of CH4, HF, and H2O as tracers, the occurrence of dehydration in the Antarctic lower stratosphere, the presence of the water vapor hygropause in the tropics, evidence of Antarctic air in the tropics, the influence of Hadley tropical upwelling, and the first global distribution of HCl, HF, and NO throughout the stratosphere. Nitric oxide measurements extend through the lower thermosphere.

  11. Initiation Train Experiments

    NASA Astrophysics Data System (ADS)

    Francois, Elizabeth; Johnson, Carl; Liechty, Gary; Whitley, Von

    2015-06-01

    In an effort to evaluate and qualify a new detonator diagnostic, booster selection and main charge configuration, a variety of small-scale tests have been conducted. This paper will describe the needs, testing approach and model validation. Because of the limited size available some novel approaches were made to understand the observed phenomenon. Function time and time of arrival at various locations in the initiation train are desirable data points. Knowing when each segment initiates the next segment and the time to run up to detonation is critical. Results of our experiments were modeled for timing accuracy, wave shape and pressure. Agreement between the experiments and models will be discussed. The testing that will be discussed is time of arrival wires, PDV, and fiber optic arrays. The time of arrival wire measures the detonator cup breakout time. When correlated to bridge burst, an absolute time is collected. This data point also gives time zero for the booster initiation. Many models actually start at the booster, rather than the detonator, so the inclusion of this data point will improve modeling efforts.

  12. The Early Experiments

    NASA Astrophysics Data System (ADS)

    Garvey, Gerald

    2013-04-01

    Stuart Freedman obtained his PhD at Berkley with an experimental thesis providing very strong evidence against theories requiring local hidden variables. He then came to Princeton in 1972 and began collaboration on a search for second-class currents. These measurements are quite difficult as the effects are the order of 1%, demonstrating Freedman's drive to take on hard but important experiments. After carrying out some relatively standard nuclear physics measurements he moved on to Stanford in 1976. There, Freedman was involved in identifying measurements sensitive to the existence of light axions. He also carried out searches for various exotica that might be produced from cosmic rays or the SLAC beam stop. During this time he was collaborating with us at Argonne investigating nuclear parity violation and time-like axial beta decay. In 1982 Freedman came to Argonne where he worked on fundamental issues in neutron beta decay. He also initiated what was to become one of his trademarks, demonstrating that surprising peaks in the e^+-e^- spectrum observed in very heavy ion collisions were spurious. He further launched his first neutrino oscillation experiment. This period of early research was marked by a remarkable diversity of subject matter and approach.

  13. Experiments on Washboard Road

    NASA Astrophysics Data System (ADS)

    Morris, Stephen; Taberlet, Nicolas; McElwaine, James; Dalziel, Stuart

    2007-03-01

    Granular surfaces to develop lateral ripples (so-called ``washboard" or ``corrugated" road) under the action of rolling wheels. Similar ripples are observed on railroad tracks and many other rolling, load bearing surfaces. Our aim was to investigate this instability of the flat road surface from the point of view of driven, dissipative granular dynamics. We report the results of both laboratory experiments and soft-particle direct numerical simulations. The experiment consisted of a rotating table 60 cm in radius with a thick layer of sand forming a roadbed around the circumference. A 6 cm radius hard rubber wheel, with a support stationary in the lab frame, rolled on the sand layer. We varied the speed of the table, the details of the grains and the suspension of the wheel. The ripple pattern appears as small patches of travelling waves which eventually spread to the entire circumference. The ripples drift slowly in the driving direction. Interesting secondary dynamics of the saturated ripples were observed, as well as various ripple creation and destruction events. The wavelength of the ripples can be quantized by the finite circumference of the road. All of these effects are captured qualitatively by 2D soft particle simulations in which a disk rolls over a 2D bed of polydisperse particles in a periodic box.

  14. Stirling machine operating experience

    SciTech Connect

    Ross, B.; Dudenhoefer, J.E.

    1994-09-01

    Numerous Stirling machines have been built and operated, but the operating experience of these machines is not well known. It is important to examine this operating experience in detail, because it largely substantiates the claim that stirling machines are capable of reliable and lengthy operating lives. The amount of data that exists is impressive, considering that many of the machines that have been built are developmental machines intended to show proof of concept, and are not expected to operate for lengthy periods of time. Some Stirling machines (typically free-piston machines) achieve long life through non-contact bearings, while other Stirling machines (typically kinematic) have achieved long operating lives through regular seal and bearing replacements. In addition to engine and system testing, life testing of critical components is also considered. The record in this paper is not complete, due to the reluctance of some organizations to release operational data and because several organizations were not contacted. The authors intend to repeat this assessment in three years, hoping for even greater participation.

  15. GPS Moving Vehicle Experiment

    NASA Technical Reports Server (NTRS)

    Oaks, O. J.; Reid, Wilson; Wright, James; Duffey, Christopher; Williams, Charles; Warren, Hugh; Zeh, Tom; Buisson, James

    1996-01-01

    The Naval Research Laboratory (NRL) in the development of timing systems for remote locations, had a technical requirement for a Y code (SA/AS) Global Positioning System (GPS) precise time transfer receiver (TTR) which could be used both in a stationary mode or mobile mode. A contract was awarded to the Stanford Telecommunication Corporation (STEL) to build such a device. The Eastern Range (ER) als had a requirement for such a receiver and entered into the contract with NRL for the procurement of additional receivers. The Moving Vehicle Experiment (MVE) described in this paper is the first in situ test of the STEL Model 5401C Time Transfer System in both stationary and mobile operations. The primary objective of the MVE was to test the timing accuracy of the newly developed GPS TTR aboard a moving vessel. To accomplish this objective, a joint experiment was performed with personnel from NRL and the er at the Atlantic Undersea Test and Evaluation Center (AUTEC) test range at Andros Island. Results and discussion of the test are presented in this paper.

  16. Droplet Combustion Experiment

    NASA Technical Reports Server (NTRS)

    Nayagam, Vedha

    1998-01-01

    Liquid fuel combustion provides a major portion of the world's energy supply. In most practical combustion devices, liquid burns after being separated into a droplet spray. Essential to the design of efficient combustion systems is a knowledge of droplet combustion behavior. The microgravity environment aboard spacecraft provides an opportunity to investigate the complex interactions between the physical and chemical combustion processes involved in droplet combustion without the complications of natural buoyancy. Launched on STS-83 and STS-94 (April 4 and July 1, 1997), the Droplet Combustion Experiment (DCE) investigated the fundamentals of droplet combustion under a range of pressures (0.25 to 1 atm), oxygen mole fractions (<0.5), and droplet sizes (1.5 to 5 mm). Principal DCE flight hardware features were a chamber to supply selected test environments, the use of crew-inserted bottles, and a vent system to remove unwanted gaseous combustion products. The internal apparatus contained the droplet deployment and ignition mechanisms to burn single, freely deployed droplets in microgravity. Diagnostics systems included a 35-mm high-speed motion picture camera (see the following sequence of photos) with a backlight to photograph burning droplets and a camcorder to monitor experiment operations. Additional diagnostics included an ultraviolet-light-sensitive CCD (charge couple discharge) camera to obtain flame radiation from hydroxyl radicals (see the final figure) and a 35-mm SLR (single-lens-reflex) camera to obtain color still photographs of the flames.

  17. Rapid Decisions From Experience

    PubMed Central

    Zeigenfuse, Matthew D.; Pleskac, Timothy J.; Liu, Taosheng

    2014-01-01

    In many everyday decisions, people quickly integrate noisy samples of information to form a preference among alternatives that offer uncertain rewards. Here, we investigated this decision process using the Flash Gambling Task (FGT), in which participants made a series of choices between a certain payoff and an uncertain alternative that produced a normal distribution of payoffs. For each choice, participants experienced the distribution of payoffs via rapid samples updated every 50 ms. We show that people can make these rapid decisions from experience and that the decision process is consistent with a sequential sampling process. Results also reveal a dissociation between these preferential decisions and equivalent perceptual decisions where participants had to determine which alternatives contained more dots on average. To account for this dissociation, we developed a sequential sampling rank-dependent utility model, which showed that participants in the FGT attended more to larger potential payoffs than participants in the perceptual task despite being given equivalent information. We discuss the implications of these findings in terms of computational models of preferential choice and a more complete understanding of experience-based decision making. PMID:24549141

  18. Lunar atmospheric composition experiment

    NASA Technical Reports Server (NTRS)

    Hoffman, J. H.

    1975-01-01

    Apollo 17 carried a miniature mass spectrometer, called the Lunar Atmospheric Composition Experiment (LACE), to the moon as part of the Apollo Lunar Surface Experiments Package (ALSEP) to study the composition and variations in the lunar atmosphere. The instrument was successfully deployed in the Taurus-Littrow Valley with its entrance aperture oriented upward to intercept and measure the downward flux of gases at the lunar surface. During the ten lunations that the LACE operated, it produced a large base of data on the lunar atmosphere, mainly collected at night time. It was found that thermal escape is the most rapid loss mechanism for hydrogen and helium. For heavier gases, photoionization followed by acceleration through the solar wind electric field accounted for most of the loss. The dominant gases on the moosn were argon and helium, and models formed for their distribution are described in detail. It is concluded that most of the helium in the lunar atmosphere is of solar wind origin, and that there also exist very small amounts of methane, ammonia, and carbon dioxide.

  19. Kinetic isolation tether experiment

    NASA Technical Reports Server (NTRS)

    Powell, J. David; He, Xiaohua; Schoder, Robert

    1988-01-01

    Progress was made on the analysis of tether damping and on experimentation of the control system on the laboratory simulator. The damping analysis considers the dynamics of a long tether connecting two spacecraft in Earth orbit, one of the spacecraft having dominant mass. In particular, it considers the material damping of the tether. The results show that, with properly chosen tether material and braiding structure, longitudinal vibration of the tethered system is well damped. A particularly effective method of implementing attitude control for tethered satellites is to use the tether tension force to generate control torques by moving the tether attach point relative to the satellite center of mass. A scaled, one dimensional laboratory simulation of the KITE mission was built and preliminary experiments of the proposed attitude control system were performed. The simulator was built to verify theoretical predictions of attitude controllability, and to investigate the technological requirements in order to implement this concept. A detailed description of the laboratory apparatus is provided, and in addition, the results of the preliminary experiments are presented and discussed.

  20. The EBEX Experiment

    SciTech Connect

    Oxley, P.; Ade, P.; Baccigalupi, C.; deBernardis, P.; Cho, H-M.; Devlin, M.J.; Hanany, S.; Johnson, B.R.; Jones, T.; Lee, A.T.; Matsumura,T.; Miller, A.D.; Milligan, M.; Renbarger, T.; Spieler, H.G.; Stompor,R.; Tucker, G.S.; Zaldarriaga, M.

    2005-01-06

    EBEX is a balloon-borne polarimeter designed to measure the intensity and polarization of the cosmic microwave background radiation. The measurements would probe the inflationary epoch that took place shortly after the big bang and would significantly improve constraints on the values of several cosmological parameters. EBEX is unique in its broad frequency coverage and in its ability to provide critical information about the level of polarized Galactic foregrounds which will be necessary for all future CMB polarization experiments. EBEX consists of a 1.5 m Dragone-type telescope that provides a resolution of less than 8 arcminutes over four focal planes each of 4. diffraction limited field of view at frequencies up to 450 GHz. The experiment is designed to accommodate 330 transition edge bolometric detectors per focal plane, for a total of up to 1320 detectors. EBEX will operate with frequency bands centered at 150, 250, 350, and 450 GHz. Polarimetry is achieved with a rotating achromatic half-wave plate. EBEX is currently in the design and construction phase, and first light is scheduled for 2008.

  1. The Virtual Arizona Experience

    NASA Astrophysics Data System (ADS)

    Allison, M. L.; Davis, R.; Conway, F. M.; Bellasai, R.

    2012-12-01

    To commemorate the once-in-a-lifetime event of Arizona's hundredth birthday, the Centennial Commission and the Governor of Arizona envisioned a museum and companion website that would capture the state's history, celebrate its people, and embrace its future. Working with world-renowned museum designers, the state began to seek ideas from across Arizona to create plans for a journey of discovery through science and the humanities. The museum would introduce visitors to some of the people who nurtured the state through its early years and others who are innovating its tomorrows. Showcases would include the resources and experiences that shaped the state's history and are transforming its present day, highlighting the ingenuity that tamed the wild frontier and is envisioning Arizona's next frontiers through science and technology. The Arizona Experience (www.arizonaexperience.org) was initially intended to serve as the web presence for the physical museum, but as delays occurred with the physical museum, the site has quickly developed an identify of its own as an interactive, multimedia experience, reaching a wider audience with functions that would be difficult or expensive to produce in a museum. As leaders in scientific and technological innovation in the state, the Arizona Geological Survey was tasked with designing and creating the Arizona Experience site. The general themes remain the same; however, the site has added content and applications that are better suited to the online environment in order to create a rich, dynamic supplement to a physical museum experience. The website offers the features and displays of the future museum with the interactive nature and learning environment of the web. This provides an encyclopedic overview of the State of Arizona by subject matter experts in a manner that is free and open to the public and erases socio-economic, political, and physical boundaries. Over the Centennial Year of 2012 the site will release a new theme and

  2. The trapped human experiment.

    PubMed

    Huo, R; Agapiou, A; Bocos-Bintintan, V; Brown, L J; Burns, C; Creaser, C S; Devenport, N A; Gao-Lau, B; Guallar-Hoyas, C; Hildebrand, L; Malkar, A; Martin, H J; Moll, V H; Patel, P; Ratiu, A; Reynolds, J C; Sielemann, S; Slodzynski, R; Statheropoulos, M; Turner, M A; Vautz, W; Wright, V E; Thomas, C L P

    2011-12-01

    This experiment observed the evolution of metabolite plumes from a human trapped in a simulation of a collapsed building. Ten participants took it in turns over five days to lie in a simulation of a collapsed building and eight of them completed the 6 h protocol while their breath, sweat and skin metabolites were passed through a simulation of a collapsed glass-clad reinforced-concrete building. Safety, welfare and environmental parameters were monitored continuously, and active adsorbent sampling for thermal desorption GC-MS, on-line and embedded CO, CO(2) and O(2) monitoring, aspirating ion mobility spectrometry with integrated semiconductor gas sensors, direct injection GC-ion mobility spectrometry, active sampling thermal desorption GC-differential mobility spectrometry and a prototype remote early detection system for survivor location were used to monitor the evolution of the metabolite plumes that were generated. Oxygen levels within the void simulator were allowed to fall no lower than 19.1% (v). Concurrent levels of carbon dioxide built up to an average level of 1.6% (v) in the breathing zone of the participants. Temperature, humidity, carbon dioxide levels and the physiological measurements were consistent with a reproducible methodology that enabled the metabolite plumes to be sampled and characterized from the different parts of the experiment. Welfare and safety data were satisfactory with pulse rates, blood pressures and oxygenation, all within levels consistent with healthy adults. Up to 12 in-test welfare assessments per participant and a six-week follow-up Stanford Acute Stress Response Questionnaire indicated that the researchers and participants did not experience any adverse effects from their involvement in the study. Preliminary observations confirmed that CO(2), NH(3) and acetone were effective markers for trapped humans, although interactions with water absorbed in building debris needed further study. An unexpected observation from the NH(3

  3. Spanish experience with cyclosporine.

    PubMed

    Pascual, J; Marcén, R; Burgos, F J; Villafruela, J J; Teruel, J L; Mampaso, F; Quereda, C; Ortuño, J

    2004-03-01

    Our experience with cyclosporine (CsA) in de novo renal transplantation (RT) may be systematized in four consecutive periods. From February 1986 to December 1989, patient survival was higher among 128 consecutive CsA-prednisone-treated cadaver allograft recipients than in previous patients on azathioprine. One-year graft survival was significantly higher in CsA patients, a difference that was thereafter progressively reduced: at 10 years graft survivals were 50% versus 45%, and at 15 years 37% versus 35%, respectively. The most frequent cause of graft loss was death with a functioning graft. Acute rejection caused more graft losses among Aza-treated patients than CsA-treated ones. However, chronic allograft nephropathy produced more graft losses in CsA patients. After this initial experience with CsA-based immunosuppression we developed a second phase in which better results were obtained in 209 first cadaveric RT recipients. The use of lower initial CsA doses, more rapid steroid tapering, and a better approach to CsA nephrotoxicity or chronic nephropathy by substantial reductions in CsA exposure and delayed azathioprine addition, lead to these improvements. From March 1995 through 2000, we used the new microemulsion CsA formulation (Neoral) with steroids or azathioprine in 110 first de novo RT recipients. Mean donor and recipient ages were significantly higher in this phase than in previous ones; consequently, survival and function results were slightly worse. Blood CsA concentrations measured 2 hours after administration represent a more precise predictor of exposure than trough concentrations. The last step in optimizing Neoral use in RT on our service was application of reduced-dosage with C2 monitoring instead of classical C0 testing. Acute rejection and treatment failure rates were low and renal allograft function improved with respect to previous full-dose C0 experiences. CsA use has evolved in these two decades in four consecutive phases. Short-term results

  4. Experience Report for WOPR

    SciTech Connect

    Pope, G

    2010-04-06

    One of the purposes of the SQA effort at LLNL is to attempt to determine the 'goodness' of the research codes used for various scientific applications. Typically these are two and three dimensional multi-physics simulation and modeling codes. These legacy research codes are used for applciations such as atmospheric dispersion modeling and analysis and prediction of the performance of engineered systems. These codes are continually subjected to automated regression test suites consisting of verified and validated expected results. Code is managed in repositories. Experience level of developers is high in the knowledge domain, platforms, and languages used. Code size of the multi-physics code used in this study was 578,242 lines excluding comment and blank lines or 5538.7 function points. Languages were 70% C++, 20% C, and 10% Fortran. The code has 130 users and a development team of 14 and an embedded SQE. The code has achieved 100% prime feature test coverage, 73.6% functional test coverage, and 71.5% statement test coverage. The average cyclomatic complexity of the code was 6.25. The codes have evolved over 10 years. Research codes are challenging because there is a desire to balance agility with discipline as well as compliance with DOE standards. Agility is important to allow experimentation with new algorithms and addition of the latest physics features. Discipline is important to increase the quality of the codes. Automation of processes and defect prevention/detection are deployed throughout the software development process. Since resarch codes are a small segment of the software industry, not much information exists in terms of reliability studies on these types of codes. This paper describes attempts to determine the goodness of these research codes. Goodness defined as both correctness of the codes and their fault densities. Correctness is determined by user interviews, peer review; feature based automated testing, and coverage measurement. This paper

  5. ARC EMCS Experiments (Seedling Growth-2) Experiment Status

    NASA Technical Reports Server (NTRS)

    Heathcote, David; Steele, Marianne

    2015-01-01

    Presentation of the status of the ARC ISS (International Space Station) Experiment, Seedling Growth-2 to the Payload Operations Investigator Working Group meeting at MSFC, Huntsville AL. The experiment employs the European Modular Cultivation System (ECMS).

  6. The Cibola flight experiment

    SciTech Connect

    Caffrey, Michael Paul; Nelson, Anthony; Salazar, Anthony; Roussel - Dupre, Diane; Katko, Kim; Palmer, Joseph; Robinson, Scott; Wirthlin, Michael; Howes, William; Richins, Daniel

    2009-01-01

    The Cibola Flight Experiment (CFE) is an experimental small satellite carrying a reconfigurable processing instrument developed at the Los Alamos National Laboratory that demonstrates the feasibility of using FPGA-based high-performance computing for sensor processing in the space environment. The CFE satellite was launched on March 8, 2007 in low-earth orbit and has operated extremely well since its deployment. The nine Xilinx Virtex FPGAs used in the payload have been used for several high-throughput sensor processing applications and for single-event upset (SEU) monitoring and mitigation. This paper will describe the CFE system and summarize its operational results. In addition, this paper will describe the results from several SEU detection circuits that were performed on the spacecraft.

  7. The 'DANTE' experiment

    NASA Astrophysics Data System (ADS)

    Freeman, Ray; Morris, Gareth A.

    2011-12-01

    The selective excitation scheme known as 'DANTE' emerged from a confluence of several ideas for new NMR experiments, some more fanciful than others. DANTE offers a simple and effective way to restrict excitation to a very narrow frequency band, usually that of a single resonance line. Initially applied to the study of individual proton-coupled carbon-13 spin multiplets, the method has been extended to water presaturation, relaxation measurements, and chemical exchange studies. Through the imposition of a magnetic field gradient it offers a simple method to enhance resolution by restricting the effective volume of the sample. Multiple DANTE excitation (with Hadamard encoding) can speed up multidimensional spectroscopy by orders of magnitude. Applied to magnetic resonance imaging, the DANTE sequence has been used to superimpose a rectangular grid onto a cardiac image, permitting motional distortions to be monitored in real time.

  8. The 'DANTE' experiment.

    PubMed

    Freeman, Ray; Morris, Gareth A

    2011-12-01

    The selective excitation scheme known as 'DANTE' emerged from a confluence of several ideas for new NMR experiments, some more fanciful than others. DANTE offers a simple and effective way to restrict excitation to a very narrow frequency band, usually that of a single resonance line. Initially applied to the study of individual proton-coupled carbon-13 spin multiplets, the method has been extended to water presaturation, relaxation measurements, and chemical exchange studies. Through the imposition of a magnetic field gradient it offers a simple method to enhance resolution by restricting the effective volume of the sample. Multiple DANTE excitation (with Hadamard encoding) can speed up multidimensional spectroscopy by orders of magnitude. Applied to magnetic resonance imaging, the DANTE sequence has been used to superimpose a rectangular grid onto a cardiac image, permitting motional distortions to be monitored in real time.

  9. The VIP experiment

    NASA Astrophysics Data System (ADS)

    Bartalucci, S.; Bertolucci, S.; Bragadireanu, M.; Catitti, M.; Cargnelli, M.; Curceanu Petrascu, C.; Di Matteo, S.; Egger, J.-P.; Guaraldo, C.; Iliescu, M.; Ishiwatari, T.; Laubenstein, M.; Marton, J.; Milotti, E.; Pietreanu, D.; Ponta, T.; Sirghi, D. L.; Sirghi, F.; Sperandio, L.; Vasquez Doce, O.; Widmann, E.; Zmeskal, J.

    2009-06-01

    The VIP (Violation of the Pauli Exclusion Principle) experiment is dedicated to check the validity of one of the basic principles of modern physics. This investigation is done searching for anomalus X-rays emitted by copper atoms in a conductor: any detection of these anomalous X-rays would mark a Pauli forbidden transition. VIP is currently taking data at the Gran Saso underground laboratories, and its scientific goal is to improve by three-four orders of magnitude the previous limit on the probability of Pauli violating transitions, bringing it into the 10-29÷ -30 region. The new experimental results and future plans are presented. The PDF file for this article was corrected and the names and affiliations were amended on 4 September 2009.

  10. Cell Radiation Experiment System

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.

    2010-01-01

    The cell radiation experiment system (CRES) is a perfused-cell culture apparatus, within which cells from humans or other animals can (1) be maintained in homeostasis while (2) being exposed to ionizing radiation during controlled intervals and (3) being monitored to determine the effects of radiation and the repair of radiation damage. The CRES can be used, for example, to determine effects of drug, radiation, and combined drug and radiation treatments on both normal and tumor cells. The CRES can also be used to analyze the effects of radiosensitive or radioprotectant drugs on cells subjected to radiation. The knowledge gained by use of the CRES is expected to contribute to the development of better cancer treatments and of better protection for astronauts, medical-equipment operators, and nuclear-power-plant workers, and others exposed frequently to ionizing radiation.

  11. THE TORMAC V EXPERIMENT

    SciTech Connect

    Brown, I.G.; Feinberg, B.; Kunkel, W.B.; Levine, M.A.; Niland, R.A.; Shaw, R.S.; Vaucher, B.G.

    1980-03-01

    Tormac (Toroidal Magnetic Cusp) is a plasma confinement concept combining the favorable MHD stability properties of a cusp geometry with the good particle confinement inherent to closed field geometry, A Tormac plasma has two regions: an interior region in which a toroidal bias or studding field is embedded, and an exterior or surface region confined by mirror trapping along open field lines. The combination of these two regions is expected to lead to a configuration having confinement substantially superior to that of a mirror. and to allow the plasma to be stable at high {beta}. The Tormac V experiment is an attempt to establish such a configuration and to investigate characteristic behavior of the Tormac plasma. In this paper we describe the Tormac concept. the Tormac V experimental set-up. and the results obtained.

  12. Nonlinear dynamics experiments

    SciTech Connect

    Fischer, W.

    2011-01-01

    The goal of nonlinear dynamics experiments is to improve the understanding of single particle effects that increase the particle amplitude and lead to loss. Particle motion in storage rings is nearly conservative and for transverse dynamics the Hamiltonian in action angle variables (I{sub x},I{sub y},{phi}{sub x},{phi}{sub y}) near an isolated resonance k{nu}{sub x} + l{nu}{sub y} {approx} p is H = I{sub x}{nu}{sub x0} + I{sub y}{nu}{sub y0} + g(I{sub x}, I{sub y}) + h(I{sub x}, I{sub y})cos(k{phi}{sub x} + l{phi}{sub y} - p{theta}), (1) where k, l, p are integers, {theta} = 2{pi}s/L is the azimuth, and s and L are the path length and circumference respectively. The amplitude dependent tunes are given by {nu}{sub x,y}(I{sub x},I{sub y}) = {nu}{sub x0,y0} + {partial_derivative}g(I{sub x},I{sub y})/{partial_derivative}I{sub x,y} (2) and h(I{sub x},I{sub y}) is the resonance driving term (RDT). If the motion is governed by multiple resonances, h(I{sub x},I{sub y}) has to be replace by a series of terms. The particle motion is completely determined by the terms g and h, which can be calculated from higher order multipoles (Sec. ??), or obtained from simulations. Deviations from pure Hamiltonian motion occur due to synchrotron radiation damping (Sec. ??) in lepton or very high energy hadron rings, parameter variations, and diffusion processes such as residual gas and intrabeam scattering. The time scale of the non-Hamiltonian process determines the applicability of the Hamiltonian analysis. Transverse nonlinearities are introduced through sextupoles or higher order multipoles and magnetic field errors in dipoles and quadrupoles. Sextupoles can already drive all resonances. The beam-beam interaction and space charge also introduce nonlinear fields. Intentionally introduced nonlinearities are used to extract beam on a resonance or through capture in stable islands. Localization and minimization of nonlinearities in a ring is a general strategy to decrease emittance growth

  13. The PANTHER User Experience

    SciTech Connect

    Coram, Jamie L.; Morrow, James D.; Perkins, David Nikolaus

    2015-09-01

    This document describes the PANTHER R&D Application, a proof-of-concept user interface application developed under the PANTHER Grand Challenge LDRD. The purpose of the application is to explore interaction models for graph analytics, drive algorithmic improvements from an end-user point of view, and support demonstration of PANTHER technologies to potential customers. The R&D Application implements a graph-centric interaction model that exposes analysts to the algorithms contained within the GeoGraphy graph analytics library. Users define geospatial-temporal semantic graph queries by constructing search templates based on nodes, edges, and the constraints among them. Users then analyze the results of the queries using both geo-spatial and temporal visualizations. Development of this application has made user experience an explicit driver for project and algorithmic level decisions that will affect how analysts one day make use of PANTHER technologies.

  14. Water Mist Experiment

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Water Mist commercial research program is scheduled to fly an investigation on STS-107 in 2002 in the updated Combustion Module (CM-2), a sophisticated combustion chamber plus diagnostic equipment. The Center for the Commercial Applications of Combustion in Space (CCACS), a NASA Commercial Space Center located at the Colorado School of Mines, is investigating the properties of mist fire suppression in microgravity with Industry Partner Environmental Engineering Concepts. These experiments consist of varying water droplet sizes and water mist concentrations applied to flame fronts of different propane/air mixtures. Observations from these tests will provide valuable information on the change of flame speed in the presence of water mist. Shown here is a flame front propagating through the Mist flame tube during 1-g testing at NASA/Glenn Research Center.

  15. The Bumpy Torus Experiment

    SciTech Connect

    Cobble, James Allen

    2016-06-09

    This document summarizes the Bumpy Torus Experiment as a viable fusion reactor concept. Conclusions reached include the following: In 30 years, order-of-magnitude technological advances have occurred in multiple areas of plasma heating and confinement. The ORNL bumpy torus of the 1970s was technology limited. Now that ITER is technology limited, an alternate concept is needed. A device built on such a concept should be current free, CW, modular, have a gentle shutdown, and demonstrable stability. The bumpy torus meets or has the potential to meet all of these criteria. Earlier, stability was not possible due to power limits; it has not been fully tested. It is time to revisit the bumpy-torus concept with a modest new machine.

  16. Wake field acceleration experiments

    SciTech Connect

    Simpson, J.D.

    1988-01-01

    Where and how will wake field acceleration devices find use for other than, possibly, accelerators for high energy physics. I don't know that this can be responsibly answered at this time. What I can do is describe some recent results from an ongoing experimental program at Argonne which support the idea that wake field techniques and devices are potentially important for future accelerators. Perhaps this will spawn expanded interest and even new ideas for the use of this new technology. The Argonne program, and in particular the Advanced Accelerator Test Facility (AATF), has been reported in several fairly recent papers and reports. But because this is a substantially new audience for the subject, I will include a brief review of the program and the facility before describing experiments. 10 refs., 7 figs.

  17. Information sciences experiment system

    NASA Technical Reports Server (NTRS)

    Katzberg, Stephen J.; Murray, Nicholas D.; Benz, Harry F.; Bowker, David E.; Hendricks, Herbert D.

    1990-01-01

    The rapid expansion of remote sensing capability over the last two decades will take another major leap forward with the advent of the Earth Observing System (Eos). An approach is presented that will permit experiments and demonstrations in onboard information extraction. The approach is a non-intrusive, eavesdropping mode in which a small amount of spacecraft real estate is allocated to an onboard computation resource. How such an approach allows the evaluation of advanced technology in the space environment, advanced techniques in information extraction for both Earth science and information science studies, direct to user data products, and real-time response to events, all without affecting other on-board instrumentation is discussed.

  18. Shooting Star Experiment

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Shooting Star Experiment (SSE) is designed to develop and demonstrate the technology required to focus the Sun's energy and use the energy for inexpensive space propulsion research. Pictured is an engineering model (Pathfinder III) of SSE and its thermal vacuum test to simulate in-orbit conditions at the X-Ray Calibration Facility at the Marshall Space Flight Center (MSFC). This model was used to test and characterize the motion and deformation of the structure caused by thermal effects. In this photograph, alignment targets are being placed on the engineering model so that a theodolite (alignment telescope) could be used to accurately measure the deformation and deflection of the engineering model under extreme condition, such as the coldness of deep space and the hotness of the Sun, as well as vacuum.

  19. The Thor tokamak experiment

    NASA Astrophysics Data System (ADS)

    Argenti, L.; Bonizzoni, G.; Cirant, S.; Corti, S.; Grosso, G.; Lampis, G.; Rossi, L.; Carretta, U.; Jacchia, A.; de Luca, F.

    1981-06-01

    The principle characteristics of plasma discharges produced in Thor tokamak experiments are discussed. The equilibrium and stability characteristics of the plasma produced are considered, with attention given to the density limits and critical streaming parameter for stable operation. The temporal evolution of the main plasma parameters, including electron density, electron temperature distribution, hard X-ray emission from suprathermal electrons, neutral gas influx, plasma density and Ohmic heating efficiency, is then examined, with particular emphasis on means used to control the electron runaway. The results achieved are noted to have demonstrated the possibility of controlling both plasma equilibrium and discharge regime, and further improvements expected by the use of more efficient preionization, gas puffing and feedback poloidal control of column position are indicated.

  20. The HOLMES Experiment

    NASA Astrophysics Data System (ADS)

    Faverzani, M.; Alpert, B.; Backer, D.; Bennet, D.; Biasotti, M.; Brofferio, C.; Ceriale, V.; Ceruti, G.; Corsini, D.; Day, P. K.; De Gerone, M.; Dressler, R.; Ferri, E.; Fowler, J.; Fumagalli, E.; Gard, J.; Gatti, F.; Giachero, A.; Hays-Wehle, J.; Heinitz, S.; Hilton, G.; Köster, U.; Lusignoli, M.; Maino, M.; Mates, J.; Nisi, S.; Nizzolo, R.; Nucciotti, A.; Orlando, A.; Parodi, L.; Pessina, G.; Pizzigoni, G.; Puiu, A.; Ragazzi, S.; Reintsema, C.; Ribeiro-Gomez, M.; Schmidt, D.; Schuman, D.; Siccardi, F.; Sisti, M.; Swetz, D.; Terranova, F.; Ullom, J.; Vale, L.

    2016-08-01

    The determination of the neutrino mass is an open issue in modern particle physics and astrophysics. The direct mass measurement is the only theory-unrelated experimental tool capable to probe such quantity. The HOLMES experiment will measure the end-point energy of the electron capture decay of ^{163}Ho, aiming at a statistical sensitivity on the neutrino mass around 1 eV/c^2. In order to acquire the large needed statistics by keeping the pile-up contribution as low as possible, 1000 transition edge sensors will be readout simultaneously with the frequency domain readout, a multiplexing technique where the multiplex factor is only limited by the bandwidth of the available commercial fast digitizers. We outline here the HOLMES project with its technical challenges, and its status and perspectives.

  1. Teneriffe, an Astronomer's Experiment

    NASA Astrophysics Data System (ADS)

    Piazzi Smyth, Charles

    2010-06-01

    Part I. The Voyage and the Climb: 1. Sailing in the Trades; 2. Santa Cruz; 3. Orotava; 4. Begin the ascent; 5. Arrival on Guajara; Part II. On the Crater of Elevation: 1. Securing the station; 2. South-west alarm; 3. Term-day work; 4. The great crater; 5. Solar radiation; 6. Whirlwinds and visitors; 7. Drought and light; 8. End of Guajara; Part III. On the Crater of Eruption: 1. Scaling the central cone; 2. Early experiences of Alta Vista; 3. Bringing up the telescope; 4. Battle of the clouds; 5. Summit of the peak; 6. Autumn in excelsis; 7. The reiterated question; 8. The ice cavern; 9. Last of the mountain; Part IV. Lowlands of Teneriffe: 1. Seasons and plants; 2. Dracoena Draco; 3. Adieu.

  2. Tribology theory versus experiment

    NASA Technical Reports Server (NTRS)

    Ferrante, John

    1987-01-01

    Tribology, the study of friction and wear of materials, has achieved a new interest because of the need for energy conservation. Fundamental understanding of this field is very complex and requires a knowledge of solid-state physics, material science, chemistry, and mechanical engineering. This paper is meant to be didactic in nature and outlines some of the considerations needed for a tribology research program. The approach is first to present a simple model, a field emission tip in contact with a flat surface, in order to elucidate important considerations, such as contact area, mechanical deformations, and interfacial bonding. Then examples from illustrative experiments are presented. Finally, the current status of physical theories concerning interfacial bonding are presented.

  3. Voyager imaging experiment

    USGS Publications Warehouse

    Smith, B.A.; Briggs, G.A.; Danielson, G.E.; Cook, A.F.; Davies, M.E.; Hunt, G.E.; Masursky, H.; Soderblom, L.A.; Owen, T.C.; Sagan, C.; Suomi, V.E.

    1977-01-01

    The overall objective of this experiment is exploratory reconnaissance of Jupiter, Saturn, their satellites, and Saturn's rings. Such reconnaissance, at resolutions and phase angles unobtainable from Earth, can be expected to provide much new data relevant to the atmospheric and/or surface properties of these bodies. The experiment also has the following specific objectives: Observe and characterize the global circulation of the atmospheres of Jupiter and Saturn; Determine the horizontal and vertical structure of the visible clouds and establish their relationship to the belted appearance and dynamical properties of the planetary atmospheres; Determine the vertical structure of high, optically-thin, scattering layers on Jupiter and Saturn; Determine the nature of anomalous features such as the Great Red Spot, South Equatorial Belt disturbances, etc.; Characterize the nature of the colored material in the clouds of Jupiter and Saturn, and identify the nature and sources of chromophores on Io and Titan; Perform comparative geologic studies of many satellites at less than 15-km resolution; Map and characterize the geologic structure of several satellites at high resolution (???1 km); Investigate the existence and nature of atmospheres on the satellites; Determine the mass, size, and shape of many of the satellites by direct measurement; Determine the direction of the spin axes and periods of rotation of several satellites, and establish coordinate systems for the larger satellites; Map the radial distribution of material in Saturn's rings at high resolution; Determine the optical scattering properties of the primaries, rings, and satellites at several wavelengths and phase angles; Search for novel physical phenomena, e.g., phenomena associated with the Io flux tube, meteors, aurorae, lightning, or satellite shadows. ?? 1977 D. Reidel Publishing Company.

  4. The Armstrong experiment revisited

    NASA Astrophysics Data System (ADS)

    Fuchs, Elmar C.; Wexler, Adam D.; Paulitsch-Fuchs, Astrid H.; Agostinho, Luewton L. F.; Yntema, Doekle; Woisetschläger, Jakob

    2014-04-01

    When a high-voltage direct-current is applied to two beakers filled with water or polar liquid dielectrica, a horizontal bridge forms between the two beakers. This experiment was first carried out by Lord Armstrong in 1893 and then forgotten until recently. Such bridges are stable by the action of electrohydrodynamic (EHD) forces caused by electric field gradients counteracting gravity. Due to these gradients a permanent pumping of liquid from one beaker into the other is observed. At macroscopic scale several of the properties of a horizontal water bridge can be explained by modern electrohydrodynamics, analyzing the motion of fluids in electric fields. Whereas on the molecular scale water can be described by quantum mechanics, there is a conceptual gap at mesoscopic scale which is bridged by a number of theories including quantum mechanical entanglement and coherent structures in water - theories that we discuss here. Much of the phenomenon is already understood, but even more can still be learned from it, since such "floating" liquid bridges resemble a small high voltage laboratory of their own: The physics of liquids in electric fields of some kV/cm can be studied, even long time experiments like neutron or light scattering are feasible since the bridge is in a steady-state equilibrium and can be kept stable for hours. It is also an electro-chemical reactor where compounds are transported through by the EHD flow, enabling the study of electrochemical reactions under potentials which are otherwise not easily accessible. Last but not least the bridge provides the experimental biologist with the opportunity to expose living organisms such as bacteria to electric fields without killing them, but with a significant influence on their behavior, and possibly, even on their genome.

  5. Turbulence modeling and experiments

    NASA Technical Reports Server (NTRS)

    Shabbir, Aamir

    1992-01-01

    The best way of verifying turbulence is to do a direct comparison between the various terms and their models. The success of this approach depends upon the availability of the data for the exact correlations (both experimental and DNS). The other approach involves numerically solving the differential equations and then comparing the results with the data. The results of such a computation will depend upon the accuracy of all the modeled terms and constants. Because of this it is sometimes difficult to find the cause of a poor performance by a model. However, such a calculation is still meaningful in other ways as it shows how a complete Reynolds stress model performs. Thirteen homogeneous flows are numerically computed using the second order closure models. We concentrate only on those models which use a linear (or quasi-linear) model for the rapid term. This, therefore, includes the Launder, Reece and Rodi (LRR) model; the isotropization of production (IP) model; and the Speziale, Sarkar, and Gatski (SSG) model. Which of the three models performs better is examined along with what are their weaknesses, if any. The other work reported deal with the experimental balances of the second moment equations for a buoyant plume. Despite the tremendous amount of activity toward the second order closure modeling of turbulence, very little experimental information is available about the budgets of the second moment equations. Part of the problem stems from our inability to measure the pressure correlations. However, if everything else appearing in these equations is known from the experiment, pressure correlations can be obtained as the closing terms. This is the closest we can come to in obtaining these terms from experiment, and despite the measurement errors which might be present in such balances, the resulting information will be extremely useful for the turbulence modelers. The purpose of this part of the work was to provide such balances of the Reynolds stress and heat

  6. Mars aqueous chemistry experiment

    NASA Technical Reports Server (NTRS)

    Clark, Benton C.; Mason, Larry W.

    1993-01-01

    The Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. Progress for the first year MACE PIDDP is reported in two major areas of effort: (1) fluids handling concepts, definition, and breadboard fabrication and (2) aqueous chemistry ion sensing technology and test facility integration. A fluids handling breadboard was designed, fabricated, and tested at Mars ambient pressure. The breadboard allows fluid manipulation scenarios to be tested under the reduced pressure conditions expected in the Martian atmosphere in order to validate valve operations, orchestrate analysis sequences, investigate sealing integrity, and to demonstrate efficacy of the fluid handling concept. Additional fluid manipulation concepts have also been developed based on updated MESUR spacecraft definition. The Mars Aqueous Chemistry Experiment Ion Selective Electrode (ISE) facility was designed as a test bed to develop a multifunction interface for measurements of chemical ion concentrations in aqueous solution. The interface allows acquisition of real time data concerning the kinetics and heats of salt dissolution, and transient response to calibration and solubility events. An array of ion selective electrodes has been interfaced and preliminary calibration studies performed.

  7. Self-assembly of the 3-aminopropyltrimethoxysilane multilayers on Si and hysteretic current-voltage characteristics

    NASA Astrophysics Data System (ADS)

    Chauhan, A. K.; Aswal, D. K.; Koiry, S. P.; Gupta, S. K.; Yakhmi, J. V.; Sürgers, C.; Guerin, D.; Lenfant, S.; Vuillaume, D.

    2008-03-01

    We report the deposition of 3-aminopropyltrimethoxysilane (APTMS) multilayers on SiOx/Si(p++) substrates by a layer-by-layer self-assembly process. The multilayers were grafted in a glove box having nitrogen ambient with both humidity and oxygen contents <1 ppm using APTMS solutions prepared in an anhydrous toluene. Deposition of the multilayers has been carried out as a function of solution concentration and grafting time. Characterization of the multilayers using static de-ionized water contact angle, ellipsometry, X-rayphotoelectron spectroscopy and atomic force microscope measurements revealed that self-assembling of the multilayers takes place in two distinct stages: (i) the first APTMS monolayer chemisorbs on a hydroxylated oxide surface by a silanization process and, (ii) the surface amino group of the first monolayer chemisorbs the hydrolyzed silane group of other APTMS molecules present in the solution, leading to the formation of a bilayer. The second stage is a self-replicating process that results in the layer-by-layer self-assembly of the multilayers with trapped NH3 + ions. The current-voltage characteristics of the multilayers exhibit a hysteresis effect along with a negative differential resistance, suggesting their potential application in the molecular memory devices. A possible mechanism for the observed hysteresis effect based on filling and de-filling of the NH3 + acting as traps is presented.

  8. Butyrylcholinesterase for protection from organophosphorus poisons; catalytic complexities and hysteretic behavior

    PubMed Central

    Masson, Patrick; Lockridge, Oksana

    2009-01-01

    Butyrylcholinesterase is a promiscuous enzyme that displays complex kinetic behavior. It is toxicologically important because it detoxifies organophosphorus poisons (OP) by making a covalent bond with the OP. The OP and the butyrylcholinesterase are both inactivated in the process. Inactivation of butyrylcholinesterase has no adverse effects. However inactivation of acetylcholinesterase in nerve synapses can be lethal. OP-inhibited butyrylcholinesterase and acetylcholinesterase can be reactivated with oximes provided the OP has not aged. Strategies for preventing the toxicity of OP include a) treatment with an OP scavenger, b) reaction of nonaged enzyme with oximes, c) reactivation of aged enzyme, d) slowing down aging with peripheral site ligands, and e) design of mutants that rapidly hydrolyze OP. Option (a) has progressed through phase I clinical trials with human butyrylcholinesterase. Option (b) is in routine clinical use. The others are at the basic research level. Butyrylcholinesterase displays complex kinetic behavior including activation by positively charged esters, ability to hydrolyze amides, and a lag time (hysteresis) preceding hydrolysis of benzoylcholine and N-methyl indoxyl acetate. Mass spectrometry has identified new OP binding motifs on tyrosine and lysine in proteins that have no active site serine. It is proposed, but not yet proven, that low dose exposure involves OP modification of proteins that have no active site serine. PMID:20004171

  9. Voltage-driven hysteretic changes in magnetization in multiferroic Co/BTO composite thin films

    NASA Astrophysics Data System (ADS)

    Shu, Li; Hu, Jia-Mian; Gao, Yao; Wu, Liang; Ma, Jing; Lin, Y. H.; Nan, C. W.

    2014-09-01

    Multiferroic Co/BaTiO3 layered composite thin films were grown on Nb-doped SrTiO3 single crystal by pulse laser deposition, in which the polycrystalline Co film was annealed under magnetic field to induce in-plane uniaxial magnetic easy axis. Voltage-induced magnetization changes along and perpendicular to the easy axis were measured by Magneto-Optical Kerr effect (MOKE) magnetometer without applied magnetic field. These changes in magnetization could be due to magnetoelectric coupling between Co and BaTiO3, and to possibly electro-optical effect of BTO if the MOKE laser could penetrate the top Co film. After excluding the electro-optical interference by analyzing the experimental results within an optical model, a hysteric loop of magnetization versus voltage is identified with a relative change in magnetization of about 8%.

  10. Maximizing hysteretic losses in magnetic ferrite nanoparticles via model-driven synthesis and materials optimization.

    PubMed

    Chen, Ritchie; Christiansen, Michael G; Anikeeva, Polina

    2013-10-22

    This article develops a set of design guidelines for maximizing heat dissipation characteristics of magnetic ferrite MFe2O4 (M = Mn, Fe, Co) nanoparticles in alternating magnetic fields. Using magnetic and structural nanoparticle characterization, we identify key synthetic parameters in the thermal decomposition of organometallic precursors that yield optimized magnetic nanoparticles over a wide range of sizes and compositions. The developed synthetic procedures allow for gram-scale production of magnetic nanoparticles stable in physiological buffer for several months. Our magnetic nanoparticles display some of the highest heat dissipation rates, which are in qualitative agreement with the trends predicted by a dynamic hysteresis model of coherent magnetization reversal in single domain magnetic particles. By combining physical simulations with robust scalable synthesis and materials characterization techniques, this work provides a pathway to a model-driven design of magnetic nanoparticles tailored to a variety of biomedical applications ranging from cancer hyperthermia to remote control of gene expression.

  11. Real space mapping of oxygen vacancy diffusion and electrochemical transformations by hysteretic current reversal curve measurements

    DOEpatents

    Kalinin, Sergei V.; Balke, Nina; Borisevich, Albina Y.; Jesse, Stephen; Maksymovych, Petro; Kim, Yunseok; Strelcov, Evgheni

    2014-06-10

    An excitation voltage biases an ionic conducting material sample over a nanoscale grid. The bias sweeps a modulated voltage with increasing maximal amplitudes. A current response is measured at grid locations. Current response reversal curves are mapped over maximal amplitudes of the bias cycles. Reversal curves are averaged over the grid for each bias cycle and mapped over maximal bias amplitudes for each bias cycle. Average reversal curve areas are mapped over maximal amplitudes of the bias cycles. Thresholds are determined for onset and ending of electrochemical activity. A predetermined number of bias sweeps may vary in frequency where each sweep has a constant number of cycles and reversal response curves may indicate ionic diffusion kinetics.

  12. Non-hysteretic superconducting quantum interference proximity transistor with enhanced responsivity

    SciTech Connect

    Jabdaraghi, R. N.; Meschke, M.; Pekola, J. P.

    2014-02-24

    This Letter presents fabrication and characterization of an optimized superconducting quantum interference proximity transistor. The present device, characterized by reduced tunnel junction area and shortened normal-metal section, demonstrates no hysteresis at low temperatures as we increased the Josephson inductance of the weak link by decreasing its cross section. It has consequently almost an order of magnitude improved magnetic field responsivity as compared to the earlier design. The modulation of both the current and the voltage across the junction have been measured as a function of magnetic flux piercing the superconducting loop.

  13. Finite-size effects of hysteretic dynamics in multilayer graphene on a ferroelectric

    DOE PAGES

    Morozovska, Anna N.; Pusenkova, Anastasiia S.; Varenyk, Oleksandr V.; ...

    2015-06-11

    The origin and influence of finite-size effects on the nonlinear dynamics of space charge stored by multilayer graphene on a ferroelectric and resistivity of graphene channel were analyzed. In this paper, we develop a self-consistent approach combining the solution of electrostatic problems with the nonlinear Landau-Khalatnikov equations for a ferroelectric. The size-dependent behaviors are governed by the relations between the thicknesses of multilayer graphene, ferroelectric film, and the dielectric layer. The appearance of charge and electroresistance hysteresis loops and their versatility stem from the interplay of polarization reversal dynamics and its incomplete screening in an alternating electric field. These featuresmore » are mostly determined by the dielectric layer thickness. The derived analytical expressions for electric fields and space-charge-density distribution in a multilayer system enable knowledge-driven design of graphene-on-ferroelectric heterostructures with advanced performance. We further investigate the effects of spatially nonuniform ferroelectric domain structures on the graphene layers’ conductivity and predict its dramatic increase under the transition from multi- to single-domain state in a ferroelectric. Finally, this intriguing effect can open possibilities for the graphene-based sensors and explore the underlying physical mechanisms in the operation of graphene field-effect transistor with ferroelectric gating.« less

  14. Finite-size effects of hysteretic dynamics in multilayer graphene on a ferroelectric

    SciTech Connect

    Morozovska, Anna N.; Pusenkova, Anastasiia S.; Varenyk, Oleksandr V.; Kalinin, Sergei V.; Eliseev, Eugene A.; Strikha, Maxym V.

    2015-06-11

    The origin and influence of finite-size effects on the nonlinear dynamics of space charge stored by multilayer graphene on a ferroelectric and resistivity of graphene channel were analyzed. In this paper, we develop a self-consistent approach combining the solution of electrostatic problems with the nonlinear Landau-Khalatnikov equations for a ferroelectric. The size-dependent behaviors are governed by the relations between the thicknesses of multilayer graphene, ferroelectric film, and the dielectric layer. The appearance of charge and electroresistance hysteresis loops and their versatility stem from the interplay of polarization reversal dynamics and its incomplete screening in an alternating electric field. These features are mostly determined by the dielectric layer thickness. The derived analytical expressions for electric fields and space-charge-density distribution in a multilayer system enable knowledge-driven design of graphene-on-ferroelectric heterostructures with advanced performance. We further investigate the effects of spatially nonuniform ferroelectric domain structures on the graphene layers’ conductivity and predict its dramatic increase under the transition from multi- to single-domain state in a ferroelectric. Finally, this intriguing effect can open possibilities for the graphene-based sensors and explore the underlying physical mechanisms in the operation of graphene field-effect transistor with ferroelectric gating.

  15. Role of open boundary conditions on the hysteretic behaviour of one-dimensional spin crossover nanoparticles

    SciTech Connect

    Chiruta, Daniel; Linares, Jorge E-mail: miya@spin.phys.s.u-tokyo.ac.jp; Boukheddaden, Kamel; Miyashita, Seiji E-mail: miya@spin.phys.s.u-tokyo.ac.jp

    2014-05-21

    In order to explain clearly the role of the open boundary conditions (OBCs) on phase transition in one dimensional system, we consider an Ising model with both short-range (J) and long-range (G) interactions, which has allowed us to study the cooperative nature of spin-crossover (SCO) materials at the nanometer scale. At this end, we developed a transfer-matrix method for one-dimensional (1D) SCO system with free boundary conditions, and we give numerical evidences for how the thermal spin transition curves vary as a function of the physical parameters (J, G) or an applied pressure. Moreover for OBCs case, we have derived the bulk, surface and finite-size contributions to the free energy and we have investigated the variation of these energies as function of J and system size. We have found that the surface free energy behaves like J〈σ〉{sup 2}, where 〈σ〉 is the average magnetization per site. Since the properties of the nanometric scale are dramatically influenced by the system's size (N), our analytical outcomes for the size dependence represent a step to achieve new characteristic of the future devices and also a way to find various novel properties which are absent in the bulk materials.

  16. Model-Based Robust Control Design for Magnetostrictive Transducers Operating in Hysteretic and Nonlinear Regimes

    DTIC Science & Technology

    2003-01-01

    ag ne tiz at io n (A /m ) Data Model −1.5 −1 −0.5 0 0.5 1 1.5 x 10 5 0 0.2 0.4 0.6 0.8 1 1.2 1.4 x 10 −3 Field (A/m) S tr ai n Data Model (a) (b...31] R.C. Smith, M.J. Dapino and S . Seelecke, “A Free Energy Model for Hysteresis in Magnetostrictive Transducers,” Journal of Applied Physics, 93(1...of Intelligent Material Systems and Structures, 11(1), pp. 62-79, 2000. [35] R.C. Smith, S . Seelecke, M.J. Dapino and Z. Ounaies, “A Unified Model

  17. Hydrology in a peaty high marsh: hysteretic flow and biogeochemical implications

    EPA Science Inventory

    Terrestrial nutrient input to coastal waters is a critical water quality problem worldwide, and salt marshes may provide a valuable nutrient buffer (either by removal or by smoothing out pulse inputs) between terrestrial sources and sensitive estuarine habitats. One of the major...

  18. Converting HAZUS capacity curves to seismic hazard-compatible building fragility functions: effect of hysteretic models

    USGS Publications Warehouse

    Ryu, Hyeuk; Luco, Nicolas; Baker, Jack W.; Karaca, Erdem

    2008-01-01

    A methodology was recently proposed for the development of hazard-compatible building fragility models using parameters of capacity curves and damage state thresholds from HAZUS (Karaca and Luco, 2008). In the methodology, HAZUS curvilinear capacity curves were used to define nonlinear dynamic SDOF models that were subjected to the nonlinear time history analysis instead of the capacity spectrum method. In this study, we construct a multilinear capacity curve with negative stiffness after an ultimate (capping) point for the nonlinear time history analysis, as an alternative to the curvilinear model provided in HAZUS. As an illustration, here we propose parameter values of the multilinear capacity curve for a moderate-code low-rise steel moment resisting frame building (labeled S1L in HAZUS). To determine the final parameter values, we perform nonlinear time history analyses of SDOF systems with various parameter values and investigate their effects on resulting fragility functions through sensitivity analysis. The findings improve capacity curves and thereby fragility and/or vulnerability models for generic types of structures.

  19. Using Hysteretic Energy to Evaluate Damping Characteristics of Hard Coating on Titanium

    DTIC Science & Technology

    2013-03-21

    26 Figure 9: Compliance Test on AISI 4140 Steel Plate ....................................................... 27...Tassini, Patsias and Lambrinou 2006). Coatings such as magnesium aluminate spinel (mag spinel) and yttria stabilized zirconia (YSZ) were common...compliance was measured by inserting a plate of AISI 4140 steel , with larger cross- sectional area than that of specimen considered for testing (Figure 9

  20. An experimental evaluation of the fully coupled hysteretic electro-mechanical behaviour of piezoelectric actuators

    NASA Astrophysics Data System (ADS)

    Butcher, Mark; Davino, Daniele; Giustiniani, Alessandro; Masi, Alessandro

    2016-04-01

    Piezoelectrics are the most commonly used of the multifunctional smart materials in industrial applications, because of their relatively low cost and ease of use in electric and electronic oriented applications. Nevertheless, while datasheets usually give just small signal quasi-static parameters, their full potential can only be exploited only if a full characterization is available because the maximum stroke or the higher piezo coupling coefficients are available at different electro-mechanical biases, where often small signal analysis is not valid. In this paper a method to get the quasi-static fully coupled characterization is presented. The method is tested on a commercial piezo actuator but can be extended to similar devices.

  1. Direct numerical simulation of electroconvective instability and hysteretic current-voltage response of a permselective membrane

    NASA Astrophysics Data System (ADS)

    Pham, Van Sang; Li, Zirui; Lim, Kian Meng; White, Jacob K.; Han, Jongyoon

    2012-10-01

    We present a systematic, multiscale, fully detailed numerical modeling for dynamics of fluid flow and ion transport covering Ohmic, limiting, and overlimiting current regimes in conductance of ion-selective membrane. By numerically solving the Poisson-Nernst-Planck-Navier-Stokes equations, it is demonstrated that the electroconvective instability, arising from the electric field acting upon the extended space charge layer, and the induced strong vortical fluid flow are the dominant factors of the overlimiting current in the planar membrane system. More importantly, at the transition between the limiting and the overlimiting current regimes, hysteresis of electric current is identified. The hysteresis demonstrates the important role of the electroconvective flow in enhancing of current in electrolyte systems with ion-selective membrane.

  2. Role of open boundary conditions on the hysteretic behaviour of one-dimensional spin crossover nanoparticles

    NASA Astrophysics Data System (ADS)

    Chiruta, Daniel; Linares, Jorge; Miyashita, Seiji; Boukheddaden, Kamel

    2014-05-01

    In order to explain clearly the role of the open boundary conditions (OBCs) on phase transition in one dimensional system, we consider an Ising model with both short-range (J) and long-range (G) interactions, which has allowed us to study the cooperative nature of spin-crossover (SCO) materials at the nanometer scale. At this end, we developed a transfer-matrix method for one-dimensional (1D) SCO system with free boundary conditions, and we give numerical evidences for how the thermal spin transition curves vary as a function of the physical parameters (J, G) or an applied pressure. Moreover for OBCs case, we have derived the bulk, surface and finite-size contributions to the free energy and we have investigated the variation of these energies as function of J and system size. We have found that the surface free energy behaves like J⟨σ⟩2, where ⟨σ⟩ is the average magnetization per site. Since the properties of the nanometric scale are dramatically influenced by the system's size (N), our analytical outcomes for the size dependence represent a step to achieve new characteristic of the future devices and also a way to find various novel properties which are absent in the bulk materials.

  3. A Preisach-Based Nonequilibrium Methodology for Simulating Performance of Hysteretic Magnetic Refrigeration Cycles

    NASA Astrophysics Data System (ADS)

    Brown, Timothy D.; Bruno, Nickolaus M.; Chen, Jing-Han; Karaman, Ibrahim; Ross, Joseph H.; Shamberger, Patrick J.

    2015-09-01

    In giant magnetocaloric effect (GMCE) materials a large entropy change couples to a magnetostructural first-order phase transition, potentially providing a basis for magnetic refrigeration cycles. However, hysteresis loss greatly reduces the availability of refrigeration work in such cycles. Here, we present a methodology combining a Preisach model for rate-independent hysteresis with a thermodynamic analysis of nonequilibrium phase transformations which, for GMCE materials exhibiting hysteresis, allows an evaluation of refrigeration work and efficiency terms for an arbitrary cycle. Using simplified but physically meaningful descriptors for the magnetic and thermal properties of a Ni45Co5Mn36.6In13.4 at.% single-crystal alloy, we relate these work/efficiency terms to fundamental material properties, demonstrating the method's use as a materials design tool. Following a simple two-parameter model for the alloy's hysteresis properties, we compute and interpret the effect of each parameter on the cyclic refrigeration work and efficiency terms. We show that hysteresis loss is a critical concern in cycles based on GMCE systems, since the resultant lost work can reduce the refrigeration work to zero; however, we also find that the lost work may be mitigated by modifying other aspects of the transition, such as the width over which the one-way transformation occurs.

  4. Experiments with Disposable Hypodermic Syringes.

    ERIC Educational Resources Information Center

    Clayton, G. T.; And Others

    1988-01-01

    Lists five experiments or demonstrations involving hypodermic syringes. The titles of experiments are Boyle's Law, Charles' Law, Atmospheric Pressure, Expansion of Gases, and Boiling at Reduced Pressure. Provides a list of materials, the typical data, and graphs where appropriate. (YP)

  5. The polarized SRF gun experiment

    SciTech Connect

    Kewisch,J.; Ben-Zvi, I.; Rao, T.; Burrill, A.; Pate, D.; Todd, R.; Wang, E.; Bluem, H.; Holmes, D.; Shultheiss, T.

    2008-10-01

    An experiment is under way to prove the feasibility of a super-conducting RF gun for the production of polarized electrons. We report on the progress of the experiment and on simulations predicting the possibility of success.

  6. Experiments in Whole Leaf Photosynthesis

    ERIC Educational Resources Information Center

    Stewart, J. C.; And Others

    1974-01-01

    Described is a simple experimental system, which uses radioactive carbon dioxide to study whole leaf photosynthesis under a variety of conditions. Other experiments and simple apparatus for the experiments are also described. (Author/RH)

  7. Partnership in Undergraduate Research Experience

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Practical laboratory and work experience has been helpful in reinforcing the undergraduate educational experience. With limited resources, individual organizations may struggle to give a student a well rounded opportunity. Most undergraduates work within internships or cooperative educational fram...

  8. The Cool Flames Experiment

    NASA Technical Reports Server (NTRS)

    Pearlman, Howard; Chapek, Richard; Neville, Donna; Sheredy, William; Wu, Ming-Shin; Tornabene, Robert

    2001-01-01

    A space-based experiment is currently under development to study diffusion-controlled, gas-phase, low temperature oxidation reactions, cool flames and auto-ignition in an unstirred, static reactor. At Earth's gravity (1g), natural convection due to self-heating during the course of slow reaction dominates diffusive transport and produces spatio-temporal variations in the thermal and thus species concentration profiles via the Arrhenius temperature dependence of the reaction rates. Natural convection is important in all terrestrial cool flame and auto-ignition studies, except for select low pressure, highly dilute (small temperature excess) studies in small vessels (i.e., small Rayleigh number). On Earth, natural convection occurs when the Rayleigh number (Ra) exceeds a critical value of approximately 600. Typical values of the Ra, associated with cool flames and auto-ignitions, range from 104-105 (or larger), a regime where both natural convection and conduction heat transport are important. When natural convection occurs, it alters the temperature, hydrodynamic, and species concentration fields, thus generating a multi-dimensional field that is extremely difficult, if not impossible, to be modeled analytically. This point has been emphasized recently by Kagan and co-workers who have shown that explosion limits can shift depending on the characteristic length scale associated with the natural convection. Moreover, natural convection in unstirred reactors is never "sufficiently strong to generate a spatially uniform temperature distribution throughout the reacting gas." Thus, an unstirred, nonisothermal reaction on Earth does not reduce to that generated in a mechanically, well-stirred system. Interestingly, however, thermal ignition theories and thermokinetic models neglect natural convection and assume a heat transfer correlation of the form: q=h(S/V)(T(bar) - Tw) where q is the heat loss per unit volume, h is the heat transfer coefficient, S/V is the surface to

  9. SPRUCE experiment data infrastructure

    NASA Astrophysics Data System (ADS)

    Krassovski, M.; Hanson, P. J.; Boden, T.; Riggs, J.; Nettles, W. R.; Hook, L. A.

    2013-12-01

    The Carbon Dioxide Information Analysis Center (CDIAC) at Oak Ridge National Laboratory (ORNL), USA has provided scientific data management support for the US Department of Energy and international climate change science since 1982. Among the many data activities CDIAC performs are design and implementation of the data systems. One current example is the data system and network for SPRUCE experiment. The SPRUCE experiment (http://mnspruce.ornl.gov) is the primary component of the Terrestrial Ecosystem Science Scientific Focus Area of ORNL's Climate Change Program, focused on terrestrial ecosystems and the mechanisms that underlie their responses to climatic change. The experimental work is to be conducted in a bog forest in northern Minnesota, 40 km north of Grand Rapids, in the USDA Forest Service Marcell Experimental Forest (MEF). The site is located at the southern margin of the boreal peatland forest. Experimental work in the 8.1-ha S1 bog will be a climate change manipulation focusing on the combined responses to multiple levels of warming at ambient or elevated CO2 (eCO2) levels. The experiment provides a platform for testing mechanisms controlling the vulnerability of organisms, biogeochemical processes and ecosystems to climatic change (e.g., thresholds for organism decline or mortality, limitations to regeneration, biogeochemical limitations to productivity, the cycling and release of CO2 and CH4 to the atmosphere). The manipulation will evaluate the response of the existing biological communities to a range of warming levels from ambient to +9°C, provided via large, modified open-top chambers. The ambient and +9°C warming treatments will also be conducted at eCO2 (in the range of 800 to 900 ppm). Both direct and indirect effects of these experimental perturbations will be analyzed to develop and refine models needed for full Earth system analyses. SPRUCE provides wide range continuous and discrete measurements. To successfully manage SPRUCE data flow

  10. The QUIJOTE experiment

    NASA Astrophysics Data System (ADS)

    López-Caniego, Marcos

    The QUIJOTE (Q-U-I JOint Tenerife) Experiment† (Rubiño-Martín et al. 2010)) is observing the polarization of the Cosmic Microwave Background and other Galactic and extragalactic signals at medium and large angular scales in the frequency range of 10-40 GHz. This experiment is going to provide valuable information about the polarization properties of synchrotron and anomalous microwave emission at these frequencies. It consists of two telescopes and three instruments located at the the Teide Observatory (2400 m) in Tenerife, Canary Islands, Spain. This project has two phases: Phase I, the first telescope (QT1) and a multi-frequency instrument (MFI) are in operations since November 2012 observing between 10 and 20 GHz. A second instrument (TGI) with 31 polarimeters working at 30 GHz is expected to start operations in Autumn 2015 and will be devoted to primordial B-mode science. This instrument will include a fixed polariser and 90 and 180 phase switches to generate four polarization states to minimize the different systematics in the receiver; Phase II, a second QUIJOTE telescope (QT2), already in operation, and a third instrument (FGI) with 40 polarimeters working at 41 GHz, safely below the 60-GHz oxygen absorption band, will significantly increment the sensitivity of the QUIJOTE project to detect the r parameter (tensor-to-scalar ratio). The reason for this is not only the significant reduction of noise due to the number of polarimeters that will incorporate but also the lower synchrotron signal from our galaxy expected at these higher frequencies. The maps obtained with the multi-frequency instrument (10-20 GHz), in combination with data from other experiments like Planck and the VLA, will be used to clean the diffuse and compact foreground emission at 30 and 40 GHz, the cosmological channels. After three years of effective observations we expect to reach the required sensitivity to detect a primordial gravitational-wave component if the tensor

  11. An artificial gravity demonstration experiment

    NASA Technical Reports Server (NTRS)

    Rupp, C.; Lemke, L.; Penzo, P.

    1989-01-01

    An artificial gravity experiment which is tethered to a Delta second stage and which uses the Small Expendable Deployer System is proposed. Following tether deployment, the Delta vehicle performs the required spin-up maneuver and can then be passivated. A surplus reentry vehicle houses the artificial gravity life science experiments. When the experiments are completed, the reentry phase of the experiment is initiated by synchronizing the spin of the configuration with the required deorbit impulse.

  12. Experiments for a Special Day

    ERIC Educational Resources Information Center

    Gluck, Paul

    2008-01-01

    Special events like science days, teacher's meetings and physics recruiting efforts require spectacular and, if possible, interactive experiments for the audience. Based on past experience with such events, we have gathered and present here a series of demonstration experiments in mechanics, optics, waves and electricity which are suitable, and…

  13. The Production of Criminological Experiments.

    ERIC Educational Resources Information Center

    Garner, Joel H.; Visher, Christy A.

    2003-01-01

    Examined the production of crime and justice field experiments in the 1990s through data on criminological experiments funded by the National Institute of Justice from 1991 through 2000. Although funds increased in this period, the number of projects and amount of funds awarded to field experiments declines. Discusses reasons for this finding.…

  14. Thought Experiments: Determining Their Meaning

    ERIC Educational Resources Information Center

    Galili, Igal

    2009-01-01

    This paper considers thought experiment as a special scientific tool that mediates between theory and experiment by mental simulation. To clarify the meaning of thought experiment, as required in teaching science, we followed the relevant episodes throughout the history of science paying attention to the epistemological status of the performed…

  15. Design Experiments in Educational Research.

    ERIC Educational Resources Information Center

    Cobb, Paul; Confrey, Jere; diSessa, Andrea; Lehrer, Richard; Schauble, Leona

    2003-01-01

    Indicates the range of purposes and variety of settings in which design experiments have been conducted, delineating five crosscutting features that collectively differentiate design experiments from other methodologies. Clarifies what is involved in preparing for and carrying out a design experiment and in conducting a retrospective analysis of…

  16. Element material experiment by EFFU

    NASA Technical Reports Server (NTRS)

    Hashimoto, Yoshihiro; Ichikawa, Masaaki; Takei, Mitsuru; Torii, Yoshihiro; Ota, Kazuo

    1995-01-01

    National Space Development Agency of JAPAN (NASDA) is planning to perform Element Material Exposure Experiment using Exposed Facility Flyer Unit (EFFU). Several materials which will be used on JEM (Japanese Experiment Module for the space station) will be exposed. Space environment monitoring is also planned in this experiment. Several ground based tests are now being performed and getting useful data.

  17. Innovative Science Experiments Using Phoenix

    ERIC Educational Resources Information Center

    Kumar, B. P. Ajith; Satyanarayana, V. V. V.; Singh, Kundan; Singh, Parmanand

    2009-01-01

    A simple, flexible and very low cost hardware plus software framework for developing computer-interfaced science experiments is presented. It can be used for developing computer-interfaced science experiments without getting into the details of electronics or computer programming. For developing experiments this is a middle path between…

  18. Neutrino cross-sections: Experiments

    SciTech Connect

    Sánchez, F.

    2015-07-15

    Neutrino-nucleus cross-sections are as of today the main source of systematic errors for oscillation experiments together with neutrino flux uncertainties. Despite recent experimental and theoretical developments, future experiments require even higher precisions in their search of CP violation. We will review the experimental status and explore possible future developments required by next generation of experiments.

  19. Young Workers: Varieties of Experience.

    ERIC Educational Resources Information Center

    Barling, Julian, Ed.; Kelloway, E. Kevin, Ed.

    This book contains nine papers devoted to the psychological experience of youth employment and its role in shaping future employment experiences and expectations. "Introduction" (Julian Barling, E. Kevin Kelloway) emphasizes the diversity of young people as a group and the diversity of individual youth's employment experience. "The…

  20. Optimal Experience of Web Activities.

    ERIC Educational Resources Information Center

    Chen, Hsiang; Wigand, R. T.; Nilan, M. S.

    1999-01-01

    Reports on Web users' optimal flow experiences to examine positive aspects of Web experiences that could be linked to theory applied to other media and then incorporated into Web design. Discusses the use of content-analytic procedures to analyze open-ended questionnaires that examined Web users' perceived flow experiences. (Author/LRW)

  1. Work Experience: Making an Impression.

    ERIC Educational Resources Information Center

    Petherbridge, Jeanette

    1997-01-01

    Interviews exploring the work experience of 11 boys and 13 girls in British high schools showed that they exhibited different levels of mature judgment and endowed their experience with different meanings. Most believed the placements' primary function was to prepare them for transition to work. The educative potential of work experience remained…

  2. First experiments with POWERPLAY.

    PubMed

    Srivastava, Rupesh Kumar; Steunebrink, Bas R; Schmidhuber, Jürgen

    2013-05-01

    Like a scientist or a playing child, POWERPLAY (Schmidhuber, 2011) not only learns new skills to solve given problems, but also invents new interesting problems by itself. By design, it continually comes up with the fastest to find, initially novel, but eventually solvable tasks. It also continually simplifies or compresses or speeds up solutions to previous tasks. Here we describe first experiments with POWERPLAY. A self-delimiting recurrent neural network SLIM RNN (Schmidhuber, 2012) is used as a general computational problem solving architecture. Its connection weights can encode arbitrary, self-delimiting, halting or non-halting programs affecting both environment (through effectors) and internal states encoding abstractions of event sequences. Our POWERPLAY-driven SLIM RNN learns to become an increasingly general solver of self-invented problems, continually adding new problem solving procedures to its growing skill repertoire. Extending a recent conference paper (Srivastava, Steunebrink, Stollenga, & Schmidhuber, 2012), we identify interesting, emerging, developmental stages of our open-ended system. We also show how it automatically self-modularizes, frequently re-using code for previously invented skills, always trying to invent novel tasks that can be quickly validated because they do not require too many weight changes affecting too many previous tasks.

  3. Enthusiastic Teachers, Vivid Experiments

    NASA Astrophysics Data System (ADS)

    Moore, John W.

    2000-04-01

    ascination with materials and chemical change is a hallmark of chemists, and it is also an important pedagogical tool. A fringe benefit of editing JCE is that I encounter so many nice people who send interesting and helpful communications. One of the first of these to cross my desk this year was from E. J. Behrman, who recommended that I read and call to your attention "Brilliant Light: A Chemical Boyhood" by Oliver Sacks, noted neurologist and author. It appeared in the December 20, 1999, issue of The New Yorker and is well worth your time and effort to find and read. Sacks's reminiscence of his boyhood interest in chemistry is fascinating. His obvious love of our science is inspiring. And he has expressed both in words that are brilliantly chosen and a joy to read. In a profile of Sacks that appeared in Chemical and Engineering News (January 10, 2000), Madeleine Jacobs relates that he is writing a book on his boyhood encounters with chemistry (to be published by Alfred A. Knopf). I am looking forward to that with great anticipation. During 1999 he also wrote an article on the periodic table in the New York Times Magazine (April 18) and an op-ed piece on chemistry sets in the New York Times (May 13). In the latter he describes how hard it is these days for a nonchemist, especially a young one, to obtain chemicals to experiment with. Chemistry sets are not what they used to be! Sacks's writings contain important messages for all of us who teach chemistry and all who are involved in piquing students' interest in our subject. A brief excerpt from his New Yorker article illustrates my point.

    I knew zinc--the dull, slightly bluish birdbath in the garden was made of zinc--and tin, from the heavy tinfoil in which sandwiches were wrapped for a picnic. My mother showed me that when tin or zinc was bent it uttered a special "cry." "It's due to deformation of the crystal structure," she said, forgetting that I was five and could not understand her

  4. Experiments on Paint Rheology

    NASA Astrophysics Data System (ADS)

    Hartranft, Thomas J.; Settles, Gary S.

    1998-11-01

    We seek a better understanding of the atomization of paints for purposes of limiting the environmental impact of spray painting. However, to do so one must confront both the shear and extensional rheology of mobile non-Newtonian fluids whose very composition is often complex and even unknown. A conventional Couette rheometer yields data on paint shear behavior, but no commercial instrument is available to measure the extensional viscosity, which is believed to govern ligamentary breakup in spray painting. Here a converging-flow extensional rheometer has been built for this purpose. Flow rate and orifice pressure drop are measured and related to the rheological properties of the fluid. At first, experience was gained by visualizing in this device the flow of clear aqueous solutions of both Newtonian (glycerol) and non-Newtonian (polyacrylamide) thickeners. Commercial latex and marine paints were then tested, with the goal of characterizing their extensional behavior and the hope that they might be replaceable by simpler aqueous rheological "substitute" fluids insofar as their atomization behavior is concerned. (Research supported by the US Navy via the Penn State Applied Research Laboratory.)

  5. [Experience with fetal pulsoxymetry].

    PubMed

    Koltai, M; Csécsei, K; Kovatsits, B

    2000-07-30

    The authors have had the opportunity to do research on an embryonic pulsoxymetre in twenty cases when traditional cardiotocographic observation and clinical symptoms had indicated intrauterine risk. The results obtained have been compared with those of a control group where embryonic pulsoxymetrical observation was not effected. The comparison was effected using the same criteria. The experiment aimed at defining how specific embryonic pulsoxymetrical observation may be if used as a screening method as well as whether its application would decrease the number of Cesarian sections. During the process of pulsoxymetrical observation, with positive change of the embryonic heart function with clear as well as meconium stained amniotic fluid, if the embryonic oxygen saturation reached levels over 30%, no Cesarian section was performed. At a saturation level under 30%, two Cesarian sections were required. In the control group without pulsoxymetrical analysis four Cesarian sections had to be performed. The oxygen saturation level of the umbilical cord artery blood of babies who underwent pulsoxymetrical observation and of those born with a Cesarian delivery were almost the same, the blood pH level was acidotic. On conclusion uterine pulsoxymetrical observation objectively reflects the intrauterine distress through fetal blood oxygenation and consequently, influences the number of Cesarian sections.

  6. Ultrafast gas switching experiments

    SciTech Connect

    Frost, C.A.; Martin, T.H.; Patterson, P.E.; Rinehart, L.F.; Rohwein, G.J.; Roose, L.D.; Aurand, J.F.; Buttram, M.T.

    1993-08-01

    We describe recent experiments which studied the physics of ultrafast gas breakdown under the extreme overvoltages which occur when a high pressure gas switch is pulse charged to hundreds of kV in 1 ns or less. The highly overvolted peaking gaps produce powerful electromagnetic pulses with risetimes < 100 ps which can be used for ultrawideband radar systems, particle accelerators, laser drivers, bioelectromagnetic studies, electromagnetic effects testing, and for basic studies of gas breakdown physics. We have produced and accurately measured pulses with 50 to 100 ps risetimes to peak levels of 75 to 160 kV at pulse repetition frequencies (PRF) to 1 kHz. A unique gas switch was developed to hold off hundreds of kV with parasitic inductance less than 1 nH. An advanced diagnostic system using Fourier compensation was developed to measure single-shot risetimes below 35 ps. The complete apparatus is described and waveforms are presented. The measured data are compared with a theoretical model which predicts key features including dependence on gas species and technology to practical systems antennas and bounded wave developed a thyristor/pulse transformer based system using a highly overvolted cable switch. This pulser driving a Sandia-designed TEM cell, provides an ultra wideband impulse with < 200 ps risetime to the test object at a PRF > Khz at > 100 kV/m E field.

  7. Ultrafast gas switching experiments

    SciTech Connect

    Frost, C.A.; Martin, T.H.; Patterson, P.E.; Rinehart, L.F.; Rohwein, G.J.; Roose, L.D.; Aurand, J.F.; Buttram, M.T.

    1996-11-01

    We describe recent experiments which studied the physics of ultrafast gas breakdown under the extreme overvoltages which occur when a high pressure gas switch is pulse charged to hundreds of kV in 1 ns or less. The highly overvolted peaking gaps produce powerful electromagnetic pulses with risetimes < 100 ps which can be used for ultrawideband radar systems, particle accelerators, laser drivers, bioelectromagnetic studies, electromagnetic effects testing, and for basic studies of gas breakdown physics. We have produced and accurately measured pulses with 50 to 100 ps risetimes to peak levels of 75 to 160 kV at pulse repetition frequencies (PRF) to I kHz. A unique gas switch was developed to hold off hundreds of kV with parasitic inductance less than I nH. An advanced diagnostic system using Fourier compensation was developed to measure single-shot risetimes below 35 ps. The complete apparatus is described and wave forms are presented. The measured data are compared with a theoretical model which predicts key features including dependence on gas species and pressure. We have applied this technology to practical systems driving ultrawideband radiating antennas and bounded wave simulators. For example, we have developed a thyristor/pulse transformer based system using a highly overvolted cable switch. This pulser driving a Sandia- designed TEM cell, provides an ultra wideband impulse with < 200 ps risetime to the test object at a PRF > 1 kHz at > 100 kV/m E field.

  8. Commissioning Experience of SNS

    SciTech Connect

    Plum, Michael A

    2007-07-01

    The Spallation Neutron Source accelerator complex consists of a 2.5 MeV H{sup -} front-end injector system, a 186 MeV normal-conducting linear accelerator, a 1 GeV superconducting linear accelerator, an accumulator ring, and associated beam transport lines. The linac was commissioned in five discrete runs, starting in 2002 and completed in 2005. The accumulator ring and associated beam transport lines were commissioned in two runs in January-February and April 2006. With the completed commissioning of the SNS accelerator, the facility has begun initial low-power operations. In the course of beam commissioning, most beam performance parameters and beam intensity goals have been achieved at low duty factor. A number of beam dynamics measurements have been performed, including emittance evolution, transverse coupling in the ring, beam instability thresholds, and beam distributions on the target. The commissioning results, achieved beam performance and initial operating experience of the SNS linac will be presented.

  9. Mars brine formation experiment

    NASA Technical Reports Server (NTRS)

    Moore, Jeffrey M.; Bullock, Mark A.; Stoker, Carol R.

    1993-01-01

    The presence of water-soluble cations and anions in the Martian regolith has been the subject of speculation for some time. Viking lander data provided evidence for salt-cemented crusts on the Martian surface. If the crusts observed at the two Viking landing sites are, in fact, cemented by salts, and these crusts are globally widespread, as IRTM-derived thermal inertia studies of the Martian surface seem to suggest, then evaporite deposits, probably at least in part derived from brines, are a major component of the Martian regolith. The composition of liquid brines in the subsurface, which not only may be major agents of physical weathering but may also presently constitute a major deep subsurface liquid reservoir, is currently unconstrained by experimental work. A knowledge of the chemical identity and rate of production of Martian brines is a critical first-order step toward understanding the nature of both these fluids and their precipitated evaporites. Laboratory experiments are being conducted to determine the identity and production rate of water-soluble ions that form in initially pure liquid water in contact with Mars-mixture gases and unaltered Mars-analog minerals.

  10. Subterranean stress engineering experiments

    SciTech Connect

    Campbell, J.R.; Colgate, S.A.; Wheat, B.M.

    1980-01-01

    The state of stress in a subterranean rock mass has classically been assumed to be constant at best. In soil with a high clay content, preconsolidation and drainage methods can lead to more stable foundation material, but methods for engineering the stresses in large masses of rock are not well known. This paper shows the results from an experiment designed to alter the in situ rock stress field in an oil shale mine. This was done by hydrofracturing the rock by use of a packed-well injection system and then propping the crack open with a thixotropic gel, which slowly hardened to the consistency of cement. Successive hydrofracture and high-pressure grouting resulted in an overstressed region. Well-head injection pressures, surface tilts, injection rates, and subterranean strains were measured and recorded on floppy disk by a Z-80 microprocessor. The results were then transmitted to the large computer system at the Los Alamos Scientific Laboratory (LASL). To put the data in a more useful form, computer-generated movies of the tilts and strains were made by use of computer graphics developed at LASL. The purpose of this paper is to present results from the Single Large Instrumented Test conducted in the Colony Oil Shale Mine near Rifle, Colorado. 13 figures.

  11. Nordic Snow Radar Experiment

    NASA Astrophysics Data System (ADS)

    Lemmetyinen, Juha; Kontu, Anna; Pulliainen, Jouni; Vehviläinen, Juho; Rautiainen, Kimmo; Wiesmann, Andreas; Mätzler, Christian; Werner, Charles; Rott, Helmut; Nagler, Thomas; Schneebeli, Martin; Proksch, Martin; Schüttemeyer, Dirk; Kern, Michael; Davidson, Malcolm W. J.

    2016-09-01

    The objective of the Nordic Snow Radar Experiment (NoSREx) campaign was to provide a continuous time series of active and passive microwave observations of snow cover at a representative location of the Arctic boreal forest area, covering a whole winter season. The activity was a part of Phase A studies for the ESA Earth Explorer 7 candidate mission CoReH2O (Cold Regions Hydrology High-resolution Observatory). The NoSREx campaign, conducted at the Finnish Meteorological Institute Arctic Research Centre (FMI-ARC) in Sodankylä, Finland, hosted a frequency scanning scatterometer operating at frequencies from X- to Ku-band. The radar observations were complemented by a microwave dual-polarization radiometer system operating from X- to W-bands. In situ measurements consisted of manual snow pit measurements at the main test site as well as extensive automated measurements on snow, ground and meteorological parameters. This study provides a summary of the obtained data, detailing measurement protocols for each microwave instrument and in situ reference data. A first analysis of the microwave signatures against snow parameters is given, also comparing observed radar backscattering and microwave emission to predictions of an active/passive forward model. All data, including the raw data observations, are available for research purposes through the European Space Agency and the Finnish Meteorological Institute. A consolidated dataset of observations, comprising the key microwave and in situ observations, is provided through the ESA campaign data portal to enable easy access to the data.

  12. Doppler wind profile experiment

    NASA Technical Reports Server (NTRS)

    Arnold, J. E.

    1985-01-01

    The data collection phase of a Doppler wind measurement experiment supported by high-resolution Jimsphere/FPS-16 wind data and Windsonde data was carried out at the Kennedy Space Center in February, March and early April of 1985. The Doppler wind measurements were made using a hybrid doppler profiler put in place by the Johnson Space Center and a SOUSY profiler operated by Radian Corporation. Both systems operated at 50 Mhz. Although the doppler profiler systems were located 10 km apart to enable concurrent operation of the systems for data comparison, little concurrent data were obtained due to set-up delays with the SOUSY system, and system problems with the WPL system during the last month of the test. During the test period, special serial Jimsphere soundings were taken at two-hour intervals on six days in March and April in addition to balloon soundings taken in support of the Shuttle launch operations. In addition, there is temperature, moisture and wind information available from the daily morning Radiosonde sounding taken at the Kennedy site. The balloon release point was at the same location as the SOUSY profiler. Vertical resolution of the SOUSY profiler was 150 M to approximately 20 km. The vertical resolution of the WPL profiler was 290 M to 10 km and 870 M to 17 km. Winds determined form the Jimsphere balloon have a vertical resolution of 30 M.

  13. SHEBA operating experience

    SciTech Connect

    Cappiello, C.C.; Butterfield, K.B.

    1997-05-01

    The Solution High Energy Burst Assembly (SHEBA) is a critical assembly fueled with a solution of 5% enriched Uranyl Fluoride, U(5%)O{sub 2}F{sub 2}. The fuel is stored in critically safe storage containers and then pumped into the ``Critical Assembly Vessel`` where the solution becomes critical. The system was designed to achieve criticality in a cylindrically symmetric configuration. The SHEBA facility also incorporates a shielding pit into which the entire assembly can be lowered to provide shielding for elevated power runs. The major goals of the SHEBA assembly project are to study the behavior of nuclear excursions in a low-enrichment solution, to evaluate accidental criticality alarm detectors for fuel-processing facilities, to provide radiation spectra and dose measurements to benchmark calculations on a low-enrichment solution system, and to provide radiation fields to calibrate personnel dosimetry. SHEBA is also being used to provide a neutron flux test bed to benchmark calculations. Rather than providing the details of these particular projects, this paper summarizes the free-run operating experience obtained as a result of the projects.

  14. A Remote Radioactivity Experiment

    NASA Astrophysics Data System (ADS)

    Jona, Kemi; Vondracek, Mark

    2013-01-01

    Imagine a high school with very few experimental resources and limited budgets that prevent the purchase of even basic laboratory equipment. For example, many high schools do not have the means of experimentally studying radioactivity because they lack Geiger counters and/or good radioactive sources. This was the case at the first high school one of us (MV) worked at, and after talking with numerous colleagues we know this is still the case at many schools. What options are there then for physics teachers to allow their students to experimentally investigate certain characteristics of radioactivity, such as how distance affects the intensity of radiation coming from a radioactive source? There are computer simulations that can be run, or perhaps the teacher has a light sensor and tries to make an analogy between the intensity of light from a light bulb and the intensity of radiation from a radioactive source based on geometric arguments to get an inverse-square law. But for many there is no direct experimental option if one does not possess a Geiger counter and good radioactive sample. It is for that teacher and class of students that an online, remote radioactivity experiment was created.

  15. Single-nucleon experiments

    SciTech Connect

    Deur, Alexandre

    2009-12-01

    We discuss the Jefferson Lab low momentum transfer data on moments of the nucleon spin structure functions $g_1$ and $g_2$ and on single charged pion electroproduction off polarized proton and polarized neutron. A wealth of data is now available, while more is being analyzed or expected to be taken in the upcoming years. Given the low momentum transfer selected by the experiments, these data can be compared to calculations from Chiral Perturbation theory, the effective theory of strong force that should describe it at low momentum transfer. The data on various moments and the respective calculations do not consistently agree. In particular, experimental data for higher moments disagree with the calculations.The absence of contribution from the $\\Delta$ resonance in the various observables was expected to facilitate the calculations and hence make the theory predictions either more robust or valid over a larger $Q^2$ range. Such expectation is verified only for the Bjorken sum, but not for other observables in which the $\\Delta$ is suppressed. Preliminary results on pion electroproduction off polarized nucleons are also presented and compared to phenomenological models for which contributions from different resonances are varied. Chiral Perturbation calculations of these observables, while not yet available, would be valuable and, together with these data, would provide an extensive test of the effective theory.

  16. Joint collaborative technology experiment

    NASA Astrophysics Data System (ADS)

    Wills, Michael; Ciccimaro, Donny; Yee, See; Denewiler, Thomas; Stroumtsos, Nicholas; Messamore, John; Brown, Rodney; Skibba, Brian; Clapp, Daniel; Wit, Jeff; Shirts, Randy J.; Dion, Gary N.; Anselmo, Gary S.

    2009-05-01

    Use of unmanned systems is rapidly growing within the military and civilian sectors in a variety of roles including reconnaissance, surveillance, explosive ordinance disposal (EOD), and force-protection and perimeter security. As utilization of these systems grows at an ever increasing rate, the need for unmanned systems teaming and inter-system collaboration becomes apparent. Collaboration provides a means of enhancing individual system capabilities through relevant data exchange that contributes to cooperative behaviors between systems and enables new capabilities not possible if the systems operate independently. A collaborative networked approach to development holds the promise of adding mission capability while simultaneously reducing the workload of system operators. The Joint Collaborative Technology Experiment (JCTE) joins individual technology development efforts within the Air Force, Navy, and Army to demonstrate the potential benefits of interoperable multiple system collaboration in a force-protection application. JCTE participants are the Air Force Research Laboratory, Materials and Manufacturing Directorate, Airbase Technologies Division, Force Protection Branch (AFRL/RXQF); the Army Aviation and Missile Research, Development, and Engineering Center Software Engineering Directorate (AMRDEC SED); and the Space and Naval Warfare Systems Center - Pacific (SSC Pacific) Unmanned Systems Branch operating with funding provided by the Joint Ground Robotics Enterprise (JGRE). This paper will describe the efforts to date in system development by the three partner organizations, development of collaborative behaviors and experimentation in the force-protection application, results and lessons learned at a technical demonstration, simulation results, and a path forward for future work.

  17. Statistics in fusion experiments

    NASA Astrophysics Data System (ADS)

    McNeill, D. H.

    1997-11-01

    Since the reasons for the variability in data from plasma experiments are often unknown or uncontrollable, statistical methods must be applied. Reliable interpretation and public accountability require full data sets. Two examples of data misrepresentation at PPPL are analyzed: Te >100 eV on S-1 spheromak.(M. Yamada, Nucl. Fusion 25, 1327 (1985); reports to DoE; etc.) The reported high values (statistical artifacts of Thomson scattering measurements) were selected from a mass of data with an average of 40 eV or less. ``Correlated'' spectroscopic data were meaningless. (2) Extrapolation to Q >=0.5 for DT in TFTR.(D. Meade et al., IAEA Baltimore (1990), V. 1, p. 9; H. P. Furth, Statements to U. S. Congress (1989).) The DD yield used there was the highest through 1990 (>= 50% above average) and the DT to DD power ratio used was about twice any published value. Average DD yields and published yield ratios scale to Q<0.15 for DT, in accord with the observed performance over the last 3 1/2 years. Press reports of outlier data from TFTR have obscured the fact that the DT behavior follows from trivial scaling of the DD data. Good practice in future fusion research would have confidence intervals and other descriptive statistics accompanying reported numerical values (cf. JAMA).

  18. Droplet Combustion Experiment (DCE)

    NASA Technical Reports Server (NTRS)

    Haggard, John B., Jr.; Nayagan, Vedha; Dryer, Frederick L.; Williams, Forman A.

    1998-01-01

    The first space-based experiments were performed on the combustion of free, individual liquid fuel droplets in oxidizing atmospheres. The fuel was heptane, with initial droplet diameters ranging about from 1 mm to 4 mm. The atmospheres were mixtures of helium and oxygen, at pressures of 1.00, 0.50 and 0.25 bar, with oxygen mole fractions between 20% and 40%, as well as normal Spacelab cabin air. The temperatures of the atmospheres and of the initial liquid fuel were nominally 300 K. A total of 44 droplets were burned successfully on the two flights, 8 on the shortened STS-83 mission and 36 on STS-94. The results spanned the full range of heptane droplet combustion behavior, from radiative flame extinction at larger droplet diameters in the more dilute atmospheres to diffusive extinction in the less dilute atmospheres, with the droplet disappearing prior to flame extinction at the highest oxygen concentrations. Quasisteady histories of droplet diameters were observed along with unsteady histories of flame diameters. New and detailed information was obtained on burning rates, flame characteristics and soot behavior. The results have motivated new computational and theoretical investigations of droplet combustion, improving knowledge of the chemical kinetics, fluid mechanics and heat and mass transfer processes involved in burning liquid fuels.

  19. Ultrafast gas switching experiments

    NASA Astrophysics Data System (ADS)

    Frost, C. A.; Martin, T. H.; Patterson, P. E.; Rinehart, L. F.; Rohwein, G. J.; Roose, L. D.; Aurand, J. F.; Buttram, M. T.

    1993-06-01

    Recent experiments which studied the physics of ultrafast gas breakdown under the extreme overvoltages which occur when a high pressure gas switch is pulse charged to hundreds of kV in 1 ns or less are described. The highly overvolted peaking gaps produce powerful electromagnetic pulses with risetimes less than 100 ps which can be used for ultrawideband radar systems, particle accelerators, laser drivers, bioelectromagnetic studies, electromagnetic effects testing, and for basic studies of gas breakdown physics. Pulses with 50 to 100 ps risetimes to peak levels of 75 to 160 kV at pulse repetition frequencies (PRF) to 1 kHz were produced and accurately measured. A unique gas switch was developed to hold off hundreds of kV with parasitic inductance less than 1 nH. An advanced diagnostic system using Fourier compensation was developed to measure single-shot risetimes below 35 ps. The complete apparatus is described and waveforms are presented. The measured data are compared with a theoretical model which predicts key features including dependence on gas species and pressure. This technology was applied to practical systems driving ultrawideband radiating antennas and bounded wave simulators. A thyristor/pulse transformer based system using a highly overvolted cable switch was developed. This pulser driving a Sandia-designed TEM cell, provides an ultra wideband impulse with less than 200 ps risetime to the test object at a PRF greater than 1 kHz at grater tha n 100 kV/m E field.

  20. Propulsion IVHM Technology Experiment

    NASA Technical Reports Server (NTRS)

    Chicatelli, Amy K.; Maul, William A.; Fulton, Christopher E.

    2006-01-01

    The Propulsion IVHM Technology Experiment (PITEX) successfully demonstrated real-time fault detection and isolation of a virtual reusable launch vehicle (RLV) main propulsion system (MPS). Specifically, the PITEX research project developed and applied a model-based diagnostic system for the MPS of the X-34 RLV, a space-launch technology demonstrator. The demonstration was simulation-based using detailed models of the propulsion subsystem to generate nominal and failure scenarios during captive carry, which is the most safety-critical portion of the X-34 flight. Since no system-level testing of the X-34 Main Propulsion System (MPS) was performed, these simulated data were used to verify and validate the software system. Advanced diagnostic and signal processing algorithms were developed and tested in real time on flight-like hardware. In an attempt to expose potential performance problems, the PITEX diagnostic system was subjected to numerous realistic effects in the simulated data including noise, sensor resolution, command/valve talkback information, and nominal build variations. In all cases, the PITEX system performed as required. The research demonstrated potential benefits of model-based diagnostics, defined performance metrics required to evaluate the diagnostic system, and studied the impact of real-world challenges encountered when monitoring propulsion subsystems.

  1. Solar array flight experiment

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Emerging satellite designs require increasing amounts of electrical power to operate spacecraft instruments and to provide environments suitable for human habitation. In the past, electrical power was generated by covering rigid honeycomb panels with solar cells. This technology results in unacceptable weight and volume penalties when large amounts of power are required. To fill the need for large-area, lightweight solar arrays, a fabrication technique in which solar cells are attached to a copper printed circuit laminated to a plastic sheet was developed. The result is a flexible solar array with one-tenth the stowed volume and one-third the weight of comparably sized rigid arrays. An automated welding process developed to attack the cells to the printed circuit guarantees repeatable welds that are more tolerant of severe environments than conventional soldered connections. To demonstrate the flight readiness of this technology, the Solar Array Flight Experiment (SAFE) was developed and flown on the space shuttle Discovery in September 1984. The tests showed the modes and frequencies of the array to be very close to preflight predictions. Structural damping, however, was higher than anticipated. Electrical performance of the active solar panel was also tested. The flight performance and postflight data evaluation are described.

  2. Polarimetric imagery collection experiment

    NASA Astrophysics Data System (ADS)

    Romano, Joao M.; Felton, Melvin; Chenault, David; Sohr, Brian

    2010-04-01

    The Spectral and Polarimetric Imagery Collection Experiment (SPICE) is a collaborative effort between the US Army ARDEC and ARL that is focused on the collection of mid-wave and long-wave infrared imagery using hyperspectral, polarimetric, and broadband sensors. The objective of the program is to collect a comprehensive database of the different modalities over the course of 1 to 2 years to capture sensor performance over a wide variety of weather conditions, diurnal, and seasonal changes inherent to Picatinny's northern New Jersey location. Using the Precision Armament Laboratory (PAL) tower at Picatinny Arsenal, the sensors will autonomously collect the desired data around the clock at different ranges where surrogate 2S3 Self-Propelled Howitzer targets are positioned at different viewing perspectives in an open field. The database will allow for: 1) Understanding of signature variability under adverse weather conditions; 2) Development of robust algorithms; 3) Development of new sensors; 4) Evaluation of polarimetric technology; and 5) Evaluation of fusing the different sensor modalities. In this paper, we will present the SPICE data collection objectives, the ongoing effort, the sensors that are currently deployed, and how this work will assist researches on the development and evaluation of sensors, algorithms, and fusion applications.

  3. Spectral imagery collection experiment

    NASA Astrophysics Data System (ADS)

    Romano, Joao M.; Rosario, Dalton; Farley, Vincent; Sohr, Brian

    2010-04-01

    The Spectral and Polarimetric Imagery Collection Experiment (SPICE) is a collaborative effort between the US Army ARDEC and ARL for the collection of mid-wave and long-wave infrared imagery using hyperspectral, polarimetric, and broadband sensors. The objective of the program is to collect a comprehensive database of the different modalities over the course of 1 to 2 years to capture sensor performance over a wide variety of adverse weather conditions, diurnal, and seasonal changes inherent to Picatinny's northern New Jersey location. Using the Precision Armament Laboratory (PAL) tower at Picatinny Arsenal, the sensors will autonomously collect the desired data around the clock at different ranges where surrogate 2S3 Self-Propelled Howitzer targets are positioned at different viewing perspectives at 549 and 1280m from the sensor location. The collected database will allow for: 1) Understand of signature variability under the different weather conditions; 2) Development of robust algorithms; 3) Development of new sensors; 4) Evaluation of hyperspectral and polarimetric technologies; and 5) Evaluation of fusing the different sensor modalities. In this paper, we will present the SPICE data collection objectives, the ongoing effort, the sensors that are currently deployed, and how this work will assist researches on the development and evaluation of sensors, algorithms, and fusion applications.

  4. Mars aqueous chemistry experiment

    NASA Technical Reports Server (NTRS)

    Clark, Benton C.; Mason, Larry W.

    1994-01-01

    Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. The second year of the MACE project has shown significant progress in two major areas. MACE Instrument concept definition is a baseline design that has been generated for the complete MACE instrument, including definition of analysis modes, mass estimates and thermal model. The design includes multiple reagent reservoirs, 10 discrete analysis cells, sample manipulation capability, and thermal control. The MACE Measurement subsystems development progress is reported regarding measurement capabilities for aqueous ion sensing, evolved gas sensing, solution conductivity measurement, reagent addition (titration) capabilities, and optical sensing of suspended particles.

  5. Cryogenic Heat Pipe Experiment (CRYOHP)

    NASA Technical Reports Server (NTRS)

    Mcintosh, Roy

    1992-01-01

    The objective of the CRYOHP experiment is to conduct a shuttle experiment that demonstrates the reliable operation of two oxygen heat pipes in microgravity. The experiment will perform the following tasks: (1) demonstrate startup of the pipes from the supercritical state; (2) measure the heat transport capacity of the pipes; (3) measure evaporator and condenser film coefficients; and (4) work shuttle safety issues. The approach for the experiment is as follows: (1) fly two axially grooved oxygen heat pipes attached to mechanical stirling cycle tactical coolers; (2) integrate experiment in hitch-hiker canister; and (3) fly on shuttle and control from ground.

  6. NASA Work Experience

    NASA Technical Reports Server (NTRS)

    Frandsen, Athela F.

    2015-01-01

    I have had the opportunity to support the analytical laboratories in chemical analysis of unknown samples, using Optical Microscopy (OM), Polarizing Light Microscopy (PLM), Fourier-Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEMEDS), and X-ray Powder Diffraction (XPD). I have assisted in characterizing fibers pulled from a spacecraft, a white fibrous residue discovered in a jet refueler truck, brown residue from a plant habitat slated for delivery to the ISS (International Space Station), corrosion on a pipe from a sprinkler, and air filtration material brought back from the ISS. I also conducted my own fiber study in order to practice techniques and further my understanding of background concepts. Furthermore, I had the opportunity to participate in diverse work assignments, where I was assigned to work with other branches of the engineering department for 1-2 days each. The first was in the Materials Science branch where I participated in the construction of the plant habitat intended for use in research aboard the ISS. The second was in the Testing Design branch where I assisted with tensile and hardness testing of over 40 samples. In addition, I have had the privilege to attend multiple tours of the NASA KSC campus, including to the Astronaut Crew Quarters, the VAB (the main area, the Columbia room, and the catwalk), the Visitor Center housing the shuttle Atlantis, the Saturn-V exhibit, the Prototype laboratory, SWAMP WORKS, the Shuttle Landing Facility, the Crawler, and the Booster Fabrication Facility (BFF). Lastly, much of my coursework prepared me for this experience, including numerous laboratory courses with topics diverse as chemistry, physics, and biology.

  7. MARE: Mars Radioactivity Experiment

    NASA Astrophysics Data System (ADS)

    di Lellis, A. M.; Capria, M. T.; Espinasse, S.; Magni, G.; Orosei, R.; Piccioni, G.; Federico, C.; Minelli, G.; Pauselli, C.; Scarpa, G.

    1999-09-01

    MARE is an experiment for the measurement of the beta and gamma radioactivity in space and in the Martian soil, both at the surface and in the subsurface. This will be accomplished by means of a dosimeter and a spectrometer. The radiation dose rate to which crews will be exposed is one of the hazards that has to be quantified before the human exploration of Mars may begin. Data for evaluating radioactivity levels at Martian surface are of great interest for environmental studies related to life in general. The dosimeter will be able to measure the beta and gamma radiation dose received, with a responsivity which is very close to that of a living organism. The dosimeter is based on thermo-luminescence pills which emit an optical signal proportional to the absorbed dose when heated. Radioactive elements ((40) K, (235) U, (238) U and (232) Th) can be used as a mean of tracing the evolution of a terrestrial planet. These radioactive elements are the source of the internal heat, which drives convection in the mantle. They have been redistributed in this process and they are now concentrated in the crust where they are accessible for study. Their different behavior during the fractionation process can be used as a mean to investigate the geochemical characteristic of Mars. The spectrometer, a scintillation radiation absorber system for single event counting, is capable of detecting gamma photons with energies between 200 KeV and 10 MeV. The detected events will be processed in such a way to allow the recognition of the spectral signature of different decay processes, and thus the identification and the measurement of the concentrations of different radionuclides in the Martian soil.

  8. Micropercutaneous nephrolithotripsy: initial experience

    PubMed Central

    Kasap, Yusuf; Ölçücüoğlu, Esin; Şirin, Mehmet Emin; Gazel, Eymen; Taştemur, Sedat; Odabas, Öner

    2015-01-01

    Introduction For small renal calculi (< 2 cm) the currently available treatment options include extracorporeal shockwave lithotripsy (ESWL), retrograde intrarenal surgery (RIRS) and standard/mini percutaneous nephrolithotomy (PNL). A new method, microperc, has therefore been developed, in which a smaller tract size and smaller instruments were used. Aim To present our clinical experiences with micropercutaneous nephrolithotripsy (microperc) in the treatment of small renal calculi. Material and methods We retrospectively evaluated patients with small renal calculi who underwent microperc between February and June 2013. A 4.8 Fr ‘all-seeing needle’ was used to achieve percutaneous renal access with the C-arm fluoroscopy guidance in the prone position. Holmium: YAG laser 272 µm fiber was used for stone fragmentation. Results A total of 20 patients underwent the microperc procedure. The mean age of the patients was 46.5 ±13.8 years. The mean stone size was 13 ±3 mm. The stone-free rate (SFR) was 90% (18/20). Two patients had clinically significant residual fragments (≥ 4 mm). The mean operation and fluoroscopy times were 107.5 ±37 min and 45 ±40 s respectively. The mean postoperative drop in hemoglobin was 1.2 ±0.9 g/dl, and 1 patient required blood transfusion. The patients were discharged after an average hospitalization of 1.4 ±0.8 days. Two complications, urinary tract infection and blood loss requiring blood transfusion, were observed in 2 patients postoperatively. Conclusions We suggest that microperc should be considered for the treatment of small renal stones. PMID:26649082

  9. Galileo Ultraviolet Spectrometer experiment

    NASA Technical Reports Server (NTRS)

    Hord, C. W.; Mcclintock, W. E.; Stewart, A. I. F.; Barth, C. A.; Esposito, L. W.; Thomas, G. E.; Sandel, B. R.; Hunten, D. M.; Broadfoot, A. L.; Shemansky, D. E.

    1992-01-01

    The Galileo ultraviolet spectrometer experiment uses data obtained by the Ultraviolet Spectrometer (UVS) mounted on the pointed orbiter scan platform and from the Extreme Ultraviolet Spectrometer (EUVS) mounted on the spinning part of the orbiter with the field of view perpendicular to the spin axis. The UVS is a Ebert-Fastie design that covers the range 113-432 nm with a wavelength resolution of 0.7 nm below 190 and 1.3 nm at longer wavelengths. The UVS spatial resolution is 0.4 deg x 0.1 deg for illuminated disk observations and 1 deg x 0.1 deg for limb geometries. The EUVS is a Voyager design objective grating spectrometer, modified to cover the wavelength range from 54 to 128 nm with wavelength resolution 3.5 nm for extended sources and 1.5 nm for point sources and spatial resolution of 0.87 deg x 0.17 deg. The EUVS instrument will follow up on the many Voyager UVS discoveries, particularly the sulfur and oxygen ion emissions in the Io torus and molecular and atomic hydrogen auroral and airglow emissions from Jupiter. The UVS will obtain spectra of emission, absorption, and scattering features in the unexplored, by spacecraft, 170-432 nm wavelength region. The UVS and EUVS instruments will provide a powerful instrument complement to investigate volatile escape and surface composition of the Galilean satellites, the Io plasma torus, micro- and macro-properties of the Jupiter clouds, and the composition structure and evolution of the Jupiter upper atmosphere.

  10. The Flare Genesis Experiment

    NASA Technical Reports Server (NTRS)

    Rust, D. M.

    2002-01-01

    Using the Flare Genesis Experiment (FGE), a balloon-borne observatory with an 80-cm solar telescope we observed the active region NOAA 8844 on January 25, 2000 for several hours. FGE was equipped with a vector polarimeter and a tunable Fabry-Perot narrow-band filter. It recorded time series of filtergrams, vector magnetograms, and Dopplergrams at the Ca(I) 6122.2 angstrom line, and H-alpha filtergrams with a cadence between 2.5 and 7.5 minutes. At the time of the observations, NOAA 8844 was located at approximately 5 N 30 W. The region was rapidly growing during the observations; new magnetic flux was constantly emerging in three supergranules near its center. We describe in detail how the FGE data were analyzed and report on the structure and behavior of peculiar moving dipolar features (MDFs) observed in the active region. In longitudinal magnetograms, the MDFs appeared to be small dipoles in the emerging fields. The east-west orientation of their polarities was opposite that of the sunspots. The dipoles were oriented parallel to their direction of motion, which was in most cases towards the sunspots. Previously, dipolar moving magnetic features have only been observed flowing out from sunspots. Vector magnetograms show that the magnetic field of each MDF negative part was less inclined to the local horizontal than the ones of the positive part. We identify the MDFs as undulations, or stitches, where the emerging flux ropes are still tied to the photosphere. We present a U-loop model that can account for their unusual structure and behavior, and it shows how emerging flux can shed its entrained mass.

  11. Welcome to the experience economy.

    PubMed

    Pine, B J; Gilmore, J H

    1998-01-01

    First there was agriculture, then manufactured goods, and eventually services. Each change represented a step up in economic value--a way for producers to distinguish their products from increasingly undifferentiated competitive offerings. Now, as services are in their turn becoming commoditized, companies are looking for the next higher value in an economic offering. Leading-edge companies are finding that it lies in staging experiences. To reach this higher level of competition, companies will have to learn how to design, sell, and deliver experiences that customers will readily pay for. An experience occurs when a company uses services as the stage--and goods as props--for engaging individuals in a way that creates a memorable event. And while experiences have always been at the heart of the entertainment business, any company stages an experience when it engages customers in a personal, memorable way. The lessons of pioneering experience providers, including the Walt Disney Company, can help companies learn how to compete in the experience economy. The authors offer five design principles that drive the creation of memorable experiences. First, create a consistent theme, one that resonates throughout the entire experience. Second, layer the theme with positive cues--for example, easy-to-follow signs. Third, eliminate negative cues, those visual or aural messages that distract or contradict the theme. Fourth, offer memorabilia that commemorate the experience for the user. Finally, engage all five senses--through sights, sounds, and so on--to heighten the experience and thus make it more memorable.

  12. Materials science experiments in space

    NASA Technical Reports Server (NTRS)

    Gelles, S. H.; Giessen, B. C.; Glicksman, M. E.; Margrave, J. L.; Markovitz, H.; Nowick, A. S.; Verhoeven, J. D.; Witt, A. F.

    1978-01-01

    The criteria for the selection of the experimental areas and individual experiments were that the experiment or area must make a meaningful contribution to the field of material science and that the space environment was either an absolute requirement for the successful execution of the experiment or that the experiment can be more economically or more conveniently performed in space. A number of experimental areas and individual experiments were recommended for further consideration as space experiments. Areas not considered to be fruitful and others needing additional analysis in order to determine their suitability for conduct in space are also listed. Recommendations were made concerning the manner in which these materials science experiments are carried out and the related studies that should be pursued.

  13. Touch massage, a rewarding experience.

    PubMed

    Lindgren, Lenita; Jacobsson, Maritha; Lämås, Kristina

    2014-12-01

    This study aims to describe and analyze healthy individuals' expressed experiences of touch massage (TM). Fifteen healthy participants received whole body touch massage during 60 minutes for two separate occasions. Interviews were analyzed by narrative analysis. Four identifiable storyline was found, Touch massage as an essential need, in this storyline the participants talked about a desire and need for human touch and TM. Another storyline was about, Touch massage as a pleasurable experience and the participants talked about the pleasure of having had TM. In the third storyline Touch massage as a dynamic experience, the informants talked about things that could modulate the experience of receiving TM. In the last storyline, Touch massage influences self-awareness, the participants described how TM affected some of their psychological and physical experiences. Experiences of touch massage was in general described as pleasant sensations and the different storylines could be seen in the light of rewarding experiences.

  14. Advanced tracking and data relay experiment study: Multimode transponder experiment

    NASA Technical Reports Server (NTRS)

    Cnossen, R. S.

    1973-01-01

    A series of experiments utilizing a multimode transponder mounted in an aircraft working either through a spacecraft or directly with a ground station is studied. The purpose of the experiments is to determine the best modulation and encoding techniques for combating RFI and multipath propagation and to determine the characteristics of VHF and UHF RFI in discreet bands. The experiments would also determine the feasibility and accuracy of range and range rate measurements with the various modulation and encoding techniques.

  15. Experience with the jet chamber of the JADE-experiment

    SciTech Connect

    Heuer, R.D.

    1984-01-01

    The jet chamber, a pictorial drift chamber used as the central track detector of the JADE experiment at PETRA, is briefly described. The present status of the spatial and dE/dx resolutions and the experience during 4 years of operation is reported. Improvement plans for the readout electronics are described and a short review of the jet chamber designed for the proposed LEP experiment OPAL is given.

  16. Wall catalysis experiment on AFE. [Aeroassist Flight Experiments

    NASA Technical Reports Server (NTRS)

    Stewart, David A.; Kolodziej, Paul

    1988-01-01

    This paper describes the wall catalysis experiment which is planned as part of the Aeroassist Flight experiments (AFE) that will be flown from the Space Shuttle Orbiter in late 1993. Research on candidate high-catalytic efficiency overcoats for the experiment conducted in an arc-jet air stream are discussed. The temperature distribution over the AFE heat shield is also predicted using a reacting boundary layer solution that includes surface kinetics and optical properties determined from these tests.

  17. The experience sampling method: Investigating students' affective experience

    NASA Astrophysics Data System (ADS)

    Nissen, Jayson M.; Stetzer, MacKenzie R.; Shemwell, Jonathan T.

    2013-01-01

    Improving non-cognitive outcomes such as attitudes, efficacy, and persistence in physics courses is an important goal of physics education. This investigation implemented an in-the-moment surveying technique called the Experience Sampling Method (ESM) [1] to measure students' affective experience in physics. Measurements included: self-efficacy, cognitive efficiency, activation, intrinsic motivation, and affect. Data are presented that show contrasts in students' experiences (e.g., in physics vs. non-physics courses).

  18. Global Troposphere Experiment Project

    NASA Technical Reports Server (NTRS)

    Bandy, Alan R.; Thornton, Donald C.

    1997-01-01

    For the Global Troposphere Experiment project Pacific Exploratory Measurements West B (PEM West B), we made determinations of sulfur dioxide (SO2) and dimethyl sulfide (DMS) using gas chromatography-mass spectrometry with isotopically labelled internal standards. This technique provides measurements with precision of 1 part-per-trillion by volume below 20 pptv and 1% above 20 pptv. Measurement of DMS and SO2 were performed with a time cycle of 5-6 minutes with intermittent zero checks. The detection limits were about 1 pptv for SO2 and 2 pptv for DMS. Over 700 measurements of each compound were made in flight. Volcanic impacts on the upper troposphere were again found as a result of deep convection in the tropics. Extensive emission of SO2 from the Pacific Rim land masses were primarily observed in the lower well-mixed part of the boundary layer but also in the upper part of the boundary layer. Analyses of the SO2 data with aerosol sulfate, beryllium-7, and lead-210 indicated that SO2, contributed to half or more of the observed total oxidized sulfur (SO2 plus aerosol sulfate) in free tropospheric air. Cloud processing and rain appeared to be responsible for lower SO2 levels between 3 and 8.5 km than above or below this region. During both phases of PEM-West, dimethyl sulfide did not appear to be a major source of sulfur dioxide in the upper free troposphere over the western Pacific Ocean. In 1991 the sources Of SO2 at high altitude appeared to be both anthropogenic and volcanic with an estimated 1% being solely from DMS. The primary difference for the increase in the DMS source was the very low concentration of SO2 at high altitude. In the midlatitude region near the Asian land masses, DMS in the mixed layer was lower than in the tropical region of the western Pacific. Convective cloud systems near volcanoes in the tropical convergence in the western Pacific troposphere were a major source of SO2 at high altitudes during PEM-West B. High levels of SO2 were

  19. Sleep paralysis as spiritual experience.

    PubMed

    Hufford, David J

    2005-03-01

    This article presents an overview of the sleep paralysis experience from both a cultural and a historical perspective. The robust, complex phenomenological pattern that represents the subjective experience of sleep paralysis is documented and illustrated. Examples are given showing that, for a majority of subjects, sleep paralysis is taken to be a kind of spiritual experience. This is, in part, because of the very common perception of a non-physical 'threatening presence' that is part of the event. Examples from various cultures, including mainstream contemporary America which has no widely known tradition about sleep paralysis, are used to show that the complex pattern and spiritual interpretation are not dependent on cultural models or prior learning. This is dramatically contrary to conventional explanations of apparently 'direct' spiritual experiences, explanations that are summed up as the 'Cultural Source Hypothesis.' This aspect of sleep paralysis was not recognized through most of the twentieth century. The article examines the way that conventional modern views of spiritual experience, combined with medical ideas that labeled 'direct' spiritual experiences as psychopathological, and mainstream religious views of such experiences as heretical if not pathological, suppressed the report and discussion of these experiences in modern society. These views have resulted in confusion in the scientific literature on sleep paralysis with regard to its prevalence and core features. The article also places sleep paralysis in the context of other 'direct' spiritual experiences and offers an 'Experiential Theory' of cross-culturally distributed spiritual experiences.

  20. Brain and conscious experience.

    PubMed

    Gazzaniga, M S

    1998-01-01

    There is a deep belief that we can attain not only a neuroscience of consciousness but a neuroscience of human consciousness. It is as if something terribly new and complex happens as the brain enlarges to its human form. Whatever this is, it triggers our capacity for self-reflection, for ennui, and for lingering moments, I would like to propose a simple, three-step suggestion. First, we should focus on what we mean when we talk about conscious experience. It is merely the awareness we have of our capacities as a species, but not the capacities themselves--only the awareness or feelings we have about them. The brain is clearly not a general purpose computing device but is a collection of circuits devoted to quite specific capacities. This is true for all brains, but what is wonderful about the human brain is that we have untold numbers of these capacities. We have more than the chimp, which has more than the monkey, which has more than the cat, which runs circles around the rat. Because we have so many specialized systems and because they can frequently do things they were not designed to do, it appears our brains have a single, general computing device. But we do not. Thus, step 1 requires that we recognize we are a collection of adaptations and, furthermore, we recognize the distinction between a species' capacities and its feelings about those capacities. Now consider step 2. Can there be any doubt that a rat at the moment of copulation is as sensorially fulfilled as a human? Of course it is. Do you think a cat does not enjoy a good piece of cod? Of course it does. Or, a monkey does not enjoy a spectacular swing? Again, it has to be true. Each species is aware of its special capacities. So, what is human consciousness? It is the very same awareness, save for the fact that we can be aware of so much more, so many wonderful things. A circuit--perhaps a single system or one duplicated over and over again--is associated with each brain capacity. The more systems a