Sample records for virtual temperature profiles

  1. BOREAS AFM-06 Mean Temperature Profile Data

    NASA Technical Reports Server (NTRS)

    Wilczak, James; Hall, Forrest G. (Editor); Newcomer, Jeffrey A. (Editor); Smith, David E. (Technical Monitor)

    2000-01-01

    The Boreal Ecosystem-Atmosphere Study (BOREAS) Airborne Fluxes and Meteorology (AFM)-6 team from the National Oceanic and Atmospheric Adminsitration/Environment Technology Laboratory (NOAA/ETL) operated a 915-MHz wind/Radio Acoustic Sounding System (RASS) profiler system in the Southern Study Area (SSA) near the Old Jack Pine (OJP) tower from 21 May 1994 to 20 Sep 1994. The data set provides temperature profiles at 15 heights, containing the variables of virtual temperature, vertical velocity, the speed of sound, and w-bar. The data are stored in tabular ASCII files. The mean temperature profile data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

  2. Intelligent neonatal monitoring based on a virtual thermal sensor

    PubMed Central

    2014-01-01

    Background Temperature measurement is a vital part of daily neonatal care. Accurate measurements are important for detecting deviations from normal values for both optimal incubator and radiant warmer functioning. The purpose of monitoring the temperature is to maintain the infant in a thermoneutral environmental zone. This physiological zone is defined as the narrow range of environmental temperatures in which the infant maintains a normal body temperature without increasing his or her metabolic rate and thus oxygen consumption. Although the temperature measurement gold standard is the skin electrode, infrared thermography (IRT) should be considered as an effortless and reliable tool for measuring and mapping human skin temperature distribution and assist in assessing thermoregulatory reflexes. Methods Body surface temperature was recorded under several clinical conditions using an infrared thermography imaging technique. Temperature distributions were recorded as real-time video, which was analyzed to evaluate mean skin temperatures. Emissivity variations were considered for optimal neonatal IRT correction for which the compensation vector was overlaid on the tracking algorithm to improve the temperature reading. Finally, a tracking algorithm was designed for active follow-up of the defined region of interest over a neonate’s geometry. Results The outcomes obtained from the thermal virtual sensor demonstrate its ability to accurately track different geometric profiles and shapes over the external anatomy of a neonate. Only a small percentage of the motion detection attempts failed to fit tracking scenarios due to the lack of a properly matching matrix for the ROI profile over neonate’s body surface. Conclusions This paper presents the design and implementation of a virtual temperature sensing application that can assist neonatologists in interpreting a neonate’s skin temperature patterns. Regarding the surface temperature, the influence of different environmental conditions inside the incubator has been confirming. PMID:24580961

  3. Intelligent neonatal monitoring based on a virtual thermal sensor.

    PubMed

    Abbas, Abbas K; Leonhardt, Steffen

    2014-03-02

    Temperature measurement is a vital part of daily neonatal care. Accurate measurements are important for detecting deviations from normal values for both optimal incubator and radiant warmer functioning. The purpose of monitoring the temperature is to maintain the infant in a thermoneutral environmental zone. This physiological zone is defined as the narrow range of environmental temperatures in which the infant maintains a normal body temperature without increasing his or her metabolic rate and thus oxygen consumption. Although the temperature measurement gold standard is the skin electrode, infrared thermography (IRT) should be considered as an effortless and reliable tool for measuring and mapping human skin temperature distribution and assist in assessing thermoregulatory reflexes. Body surface temperature was recorded under several clinical conditions using an infrared thermography imaging technique. Temperature distributions were recorded as real-time video, which was analyzed to evaluate mean skin temperatures. Emissivity variations were considered for optimal neonatal IRT correction for which the compensation vector was overlaid on the tracking algorithm to improve the temperature reading. Finally, a tracking algorithm was designed for active follow-up of the defined region of interest over a neonate's geometry. The outcomes obtained from the thermal virtual sensor demonstrate its ability to accurately track different geometric profiles and shapes over the external anatomy of a neonate. Only a small percentage of the motion detection attempts failed to fit tracking scenarios due to the lack of a properly matching matrix for the ROI profile over neonate's body surface. This paper presents the design and implementation of a virtual temperature sensing application that can assist neonatologists in interpreting a neonate's skin temperature patterns. Regarding the surface temperature, the influence of different environmental conditions inside the incubator has been confirming.

  4. Assessing the accuracy of microwave radiometers and radio acoustic sounding systems for wind energy applications

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

    Bianco, Laura; Friedrich, Katja; Wilczak, James M.

    To assess current remote-sensing capabilities for wind energy applications, a remote-sensing system evaluation study, called XPIA (eXperimental Planetary boundary layer Instrument Assessment), was held in the spring of 2015 at NOAA's Boulder Atmospheric Observatory (BAO) facility. Several remote-sensing platforms were evaluated to determine their suitability for the verification and validation processes used to test the accuracy of numerical weather prediction models.The evaluation of these platforms was performed with respect to well-defined reference systems: the BAO's 300 m tower equipped at six levels (50, 100, 150, 200, 250, and 300 m) with 12 sonic anemometers and six temperature ( T) andmore » relative humidity (RH) sensors; and approximately 60 radiosonde launches.In this study we first employ these reference measurements to validate temperature profiles retrieved by two co-located microwave radiometers (MWRs) as well as virtual temperature ( T v) measured by co-located wind profiling radars equipped with radio acoustic sounding systems (RASSs). Results indicate a mean absolute error (MAE) in the temperature retrieved by the microwave radiometers below 1.5 K in the lowest 5?km of the atmosphere and a mean absolute error in the virtual temperature measured by the radio acoustic sounding systems below 0.8 K in the layer of the atmosphere covered by these measurements (up to approximately 1.6-2 km). We also investigated the benefit of the vertical velocity correction applied to the speed of sound before computing the virtual temperature by the radio acoustic sounding systems. We find that using this correction frequently increases the RASS error, and that it should not be routinely applied to all data.Water vapor density (WVD) profiles measured by the MWRs were also compared with similar measurements from the soundings, showing the capability of MWRs to follow the vertical profile measured by the sounding and finding a mean absolute error below 0.5 g m -3 in the lowest 5 km of the atmosphere. However, the relative humidity profiles measured by the microwave radiometer lack the high-resolution details available from radiosonde profiles. Furthermore, an encouraging and significant finding of this study was that the coefficient of determination between the lapse rate measured by the microwave radiometer and the tower measurements over the tower levels between 50 and 300 m ranged from 0.76 to 0.91, proving that these remote-sensing instruments can provide accurate information on atmospheric stability conditions in the lower boundary layer.« less

  5. Assessing the accuracy of microwave radiometers and radio acoustic sounding systems for wind energy applications

    DOE PAGES

    Bianco, Laura; Friedrich, Katja; Wilczak, James M.; ...

    2017-05-09

    To assess current remote-sensing capabilities for wind energy applications, a remote-sensing system evaluation study, called XPIA (eXperimental Planetary boundary layer Instrument Assessment), was held in the spring of 2015 at NOAA's Boulder Atmospheric Observatory (BAO) facility. Several remote-sensing platforms were evaluated to determine their suitability for the verification and validation processes used to test the accuracy of numerical weather prediction models.The evaluation of these platforms was performed with respect to well-defined reference systems: the BAO's 300 m tower equipped at six levels (50, 100, 150, 200, 250, and 300 m) with 12 sonic anemometers and six temperature ( T) andmore » relative humidity (RH) sensors; and approximately 60 radiosonde launches.In this study we first employ these reference measurements to validate temperature profiles retrieved by two co-located microwave radiometers (MWRs) as well as virtual temperature ( T v) measured by co-located wind profiling radars equipped with radio acoustic sounding systems (RASSs). Results indicate a mean absolute error (MAE) in the temperature retrieved by the microwave radiometers below 1.5 K in the lowest 5?km of the atmosphere and a mean absolute error in the virtual temperature measured by the radio acoustic sounding systems below 0.8 K in the layer of the atmosphere covered by these measurements (up to approximately 1.6-2 km). We also investigated the benefit of the vertical velocity correction applied to the speed of sound before computing the virtual temperature by the radio acoustic sounding systems. We find that using this correction frequently increases the RASS error, and that it should not be routinely applied to all data.Water vapor density (WVD) profiles measured by the MWRs were also compared with similar measurements from the soundings, showing the capability of MWRs to follow the vertical profile measured by the sounding and finding a mean absolute error below 0.5 g m -3 in the lowest 5 km of the atmosphere. However, the relative humidity profiles measured by the microwave radiometer lack the high-resolution details available from radiosonde profiles. Furthermore, an encouraging and significant finding of this study was that the coefficient of determination between the lapse rate measured by the microwave radiometer and the tower measurements over the tower levels between 50 and 300 m ranged from 0.76 to 0.91, proving that these remote-sensing instruments can provide accurate information on atmospheric stability conditions in the lower boundary layer.« less

  6. Assessing the accuracy of microwave radiometers and radio acoustic sounding systems for wind energy applications

    NASA Astrophysics Data System (ADS)

    Bianco, Laura; Friedrich, Katja; Wilczak, James M.; Hazen, Duane; Wolfe, Daniel; Delgado, Ruben; Oncley, Steven P.; Lundquist, Julie K.

    2017-05-01

    To assess current remote-sensing capabilities for wind energy applications, a remote-sensing system evaluation study, called XPIA (eXperimental Planetary boundary layer Instrument Assessment), was held in the spring of 2015 at NOAA's Boulder Atmospheric Observatory (BAO) facility. Several remote-sensing platforms were evaluated to determine their suitability for the verification and validation processes used to test the accuracy of numerical weather prediction models.The evaluation of these platforms was performed with respect to well-defined reference systems: the BAO's 300 m tower equipped at six levels (50, 100, 150, 200, 250, and 300 m) with 12 sonic anemometers and six temperature (T) and relative humidity (RH) sensors; and approximately 60 radiosonde launches.In this study we first employ these reference measurements to validate temperature profiles retrieved by two co-located microwave radiometers (MWRs) as well as virtual temperature (Tv) measured by co-located wind profiling radars equipped with radio acoustic sounding systems (RASSs). Results indicate a mean absolute error (MAE) in the temperature retrieved by the microwave radiometers below 1.5 K in the lowest 5 km of the atmosphere and a mean absolute error in the virtual temperature measured by the radio acoustic sounding systems below 0.8 K in the layer of the atmosphere covered by these measurements (up to approximately 1.6-2 km). We also investigated the benefit of the vertical velocity correction applied to the speed of sound before computing the virtual temperature by the radio acoustic sounding systems. We find that using this correction frequently increases the RASS error, and that it should not be routinely applied to all data.Water vapor density (WVD) profiles measured by the MWRs were also compared with similar measurements from the soundings, showing the capability of MWRs to follow the vertical profile measured by the sounding and finding a mean absolute error below 0.5 g m-3 in the lowest 5 km of the atmosphere. However, the relative humidity profiles measured by the microwave radiometer lack the high-resolution details available from radiosonde profiles. An encouraging and significant finding of this study was that the coefficient of determination between the lapse rate measured by the microwave radiometer and the tower measurements over the tower levels between 50 and 300 m ranged from 0.76 to 0.91, proving that these remote-sensing instruments can provide accurate information on atmospheric stability conditions in the lower boundary layer.

  7. Surface tension and phase coexistence properties of the lattice fluid from a virtual site removal Monte Carlo strategy

    NASA Astrophysics Data System (ADS)

    Provata, Astero; Prassas, Vassilis D.; Theodorou, Doros N.

    1997-10-01

    A thin liquid film of lattice fluid in equilibrium with its vapor is studied in 2 and 3 dimensions with canonical Monte Carlo simulation (MC) and Self-Consistent Field Theory (SCF) in the temperature range 0.45Tc to Tc, where Tc the liquid-gas critical temperature. Extending the approach of Oates et al. [Philos. Mag. B 61, 337 (1990)] to anisotropic systems, we develop a method for the MC computation of the transverse and normal pressure profiles, hence of the surface tension, based on virtual removals of individual sites or blocks of sites from the system. Results from implementation of this new method, obtained at very modest computational cost, are in reasonable agreement with exact values and other MC estimates of the surface tension of the 2-d and 3-d model systems, respectively. SCF estimates of the interfacial density profiles, the surface tension, the vapor pressure curve and the binodal curve compare well with MC results away from Tc, but show the expected deviations at high temperatures.

  8. A NARX damper model for virtual tuning of automotive suspension systems with high-frequency loading

    NASA Astrophysics Data System (ADS)

    Alghafir, M. N.; Dunne, J. F.

    2012-02-01

    A computationally efficient NARX-type neural network model is developed to characterise highly nonlinear frequency-dependent thermally sensitive hydraulic dampers for use in the virtual tuning of passive suspension systems with high-frequency loading. Three input variables are chosen to account for high-frequency kinematics and temperature variations arising from continuous vehicle operation over non-smooth surfaces such as stone-covered streets, rough or off-road conditions. Two additional input variables are chosen to represent tuneable valve parameters. To assist in the development of the NARX model, a highly accurate but computationally excessive physical damper model [originally proposed by S. Duym and K. Reybrouck, Physical characterization of non-linear shock absorber dynamics, Eur. J. Mech. Eng. M 43(4) (1998), pp. 181-188] is extended to allow for high-frequency input kinematics. Experimental verification of this extended version uses measured damper data obtained from an industrial damper test machine under near-isothermal conditions for fixed valve settings, with input kinematics corresponding to harmonic and random road profiles. The extended model is then used only for simulating data for training and testing the NARX model with specified temperature profiles and different valve parameters, both in isolation and within quarter-car vehicle simulations. A heat generation and dissipation model is also developed and experimentally verified for use within the simulations. Virtual tuning using the quarter-car simulation model then exploits the NARX damper to achieve a compromise between ride and handling under transient thermal conditions with harmonic and random road profiles. For quarter-car simulations, the paper shows that a single tuneable NARX damper makes virtual tuning computationally very attractive.

  9. Greenhouse effects on Venus

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    Calculations that used Pioneer-Venus measurements of atmosphere composition, temperature profiles, and radiative heating predicted Venus' surface temperature ‘very precisely,’ says the Ames Research Center. The calculations predict not only Venus' surface temperature but agree with temperatures measured at various altitudes above the surface by the four Pioneer Venus atmosphere probe craft.Using Pioneer-Venus spacecraft data, a research team has virtually proved that the searing 482° C surface temperature of Venus is due to an atmospheric greenhouse effect. Until now the Venus greenhouse effect has been largely a theory.

  10. Description, accessibility and usage of SOIR/Venus Express atmospheric profiles of Venus distributed in VESPA (Virtual European Solar and Planetary Access)

    NASA Astrophysics Data System (ADS)

    Trompet, L.; Geunes, Y.; Ooms, T.; Mahieux, A.; Wilquet, V.; Chamberlain, S.; Robert, S.; Thomas, I. R.; Erard, S.; Cecconi, B.; Le Sidaner, P.; Vandaele, A. C.

    2018-01-01

    Venus Express SOIR profiles of pressure, temperature and number densities of different constituents of the mesosphere and lower thermosphere of Venus are the only experimental data covering the 60 km to 220 km range of altitudes at the terminator of Venus. This unique dataset is now available in the open access VESPA infrastructure. This paper describes the content of these data products and provides some use cases.

  11. Comparison of Gas Displacement based on Thermometry in the Pulse Tube with Rayleigh Scattering

    NASA Astrophysics Data System (ADS)

    Hagiwara, Yasumasa; Nara, Kenichi; Ito, Seitoku; Saito, Takamoto

    A pulse tube refrigerator has high reliability because of its simple structure. Recently the level of development activity of the pulse tube refrigerator has increased, but the quantitative understanding of the refrigeration mechanism has not fully been obtained. Therefore various explanations were proposed. The concept of virtual gas piston in particular helps us to understand the function of a phase shifter such as a buffer tank and an orifice because the virtual gas piston corresponds to a piston of a Stirling refrigerator. However it is difficult to directly measure the averaged gas displacement which corresponds to the virtual gas piston because uniform gas flow such as a gas piston does not always exist. For example, there are a jet flow from orifice and circulated flows in a pulse tube, which are predicted theoretically. In spite of these phenomena, the averaged gas displacement is very important in practical use because it can simply predict the performance from the displacement. In this report, we calculate the averaged gas displacement and mass flow through an orifice. The mass flow is calculated from the pressure change in a buffer tank. The averaged gas displacement is calculated from temperature profiles in the pulse tube and the mass flow. It is necessary to measure temperature in the pulse tube as widely as possible in order to calculate the averaged gas displacement. We apply a method using the Rayleigh Scattering the thermometry in the pulse tube. With this method, it is possible to perform 2-dimensional measurement without disturbing the gas flow. By this method, the averaged gas displacements and the temperature profiles of basic and orifice types of refrigeration were compared.

  12. Three-Dimensional Temperature and Wind Profiles Obtained Using UAV-Based Acoustic Atmospheric Tomography

    NASA Astrophysics Data System (ADS)

    Finn, A.

    2017-12-01

    The natural sound generated by an unmanned aerial vehicle is used in conjunction with tomography to remotely sense atmospheric temperature and wind profiles simultaneously. Sound fields recorded onboard the aircraft and by an array of microphones on the ground are compared and converted to sound speed estimates for the ray paths intersecting the intervening medium. Tomographic inversion is then used to transform these sound speed values into vertical cross-sections and 3D volumes of virtual temperature and wind vectors, which enables the atmosphere to be visualised and monitored over time up to altitudes of 1,200m and over baselines of up to 600m. This paper reports on results from two short campaigns during which 2D and 3D profiles of wind and temperature obtained in this way were compared to: measurements taken by co-located mid-range Doppler SODAR and LIDAR; and temperature measurements made by instruments carried by unmanned aircraft flying through the intervening atmosphere. Large eddy simulation of daytime atmospheric boundary layers were also used to examine the anticipated performance of the instruments and the nature of any errors. The observations obtained using all systems are shown to correspond closely.

  13. Testing the Data Assimilation Capability of the Profiler Virtual Module

    DTIC Science & Technology

    2016-02-01

    ARL-TR-7601 ● FEB 2016 US Army Research Laboratory Testing the Data Assimilation Capability of the Profiler Virtual Module by...originator. ARL-TR-7601 ● FEB 2016 US Army Research Laboratory Testing the Data Assimilation Capability of the Profiler Virtual...hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and

  14. Progress report: Continued development of an integrated sounding system in support of the DOE/ARM experimental program

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

    Edgeworth R. Westwater; Kenneth S. Gage; Yong Han

    1996-09-06

    From January 6 to February 28, 1993, the second phase of the Prototype Radiation Observation Experiment (PROBE) was conducted in Kavieng, Papua New Guinea. Data taken during PROBE included frequent radiosondes, 915 MHz Wind profiler/Radio Acoustic Sounding System (RASS) observations of winds and temperatures, and lidar measurements of cloud-base heights. In addition, a dual-channel Microwave Water Substance Radiometer (MWSR) at 23.87 and 31.65 GHz and a Fourier Transform Infrared Radiometer (FTIR) were operated. The FTIR operated between 500 and 2000 cm{sup -1} and measured some of the first high spectral resolution (1 cm{sup -1}) radiation data taken in the tropics.more » The microwave radiometer provided continuous measurements with 30-second resolution of precipitable water vapor (PWV) and integrated cloud liquid (ICL), the RASS measured virtual temperature profiles every 30 minutes, and the cloud lidar provided episodic measurements of clouds every minute. The RASS, MWSR, and FTIR data taken during PROBE were compared with radiosonde data. Broadband longwave and shortwave irradiance data and lidar data were used to identify the presence of cirrus clouds and clear conditions. Comparisons were made between measured and calculated radiance during clear conditions, using radiosonde data as input to a Line-By-Line Radiative Transfer Model. Comparisons of RASS-measured virtual temperature with radiosonde data revealed a significant cold bias below 500 m.« less

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

    Huang, Z; Jiang, W; Stuart, B

    Purpose: Since electrons are easily scattered, the virtual source position for electrons is expected to locate below the x-ray target of Medical Linacs. However, the effective SSD method yields the electron virtual position above the x-ray target for some applicators for some energy in Siemens Linacs. In this study, we propose to use IC Profiler (Sun Nuclear) for evaluating the electron virtual source position for the standard electron applicators for various electron energies. Methods: The profile measurements for various nominal source-to-detector distances (SDDs) of 100–115 cm were carried out for electron beam energies of 6–18 MeV. Two methods were used:more » one was to use a 0.125 cc ion chamber (PTW, Type 31010) with buildup mounted in a PTW water tank without water filled; and the other was to use IC Profiler with a buildup to achieve charge particle equilibrium. The full width at half-maximum (FWHM) method was used to determine the field sizes for the measured profiles. Backprojecting (by a straight line) the distance between the 50% points on the beam profiles for the various SDDs, yielded the virtual source position for each applicator. Results: The profiles were obtained and the field sizes were determined by FWHM. The virtual source positions were determined through backprojection of profiles for applicators (5, 10, 15, 20, 25). For instance, they were 96.415 cm (IC Profiler) vs 95.844 cm (scanning ion chamber) for 9 MeV electrons with 10×10 cm applicator and 97.160 cm vs 97.161 cm for 12 MeV electrons with 10×10 cm applicator. The differences in the virtual source positions between IC profiler and scanning ion chamber were within 1.5%. Conclusion: IC Profiler provides a practical method for determining the electron virtual source position and its results are consistent with those obtained by profiles of scanning ion chamber with buildup.« less

  16. Virtual environment assessment for laser-based vision surface profiling

    NASA Astrophysics Data System (ADS)

    ElSoussi, Adnane; Al Alami, Abed ElRahman; Abu-Nabah, Bassam A.

    2015-03-01

    Oil and gas businesses have been raising the demand from original equipment manufacturers (OEMs) to implement a reliable metrology method in assessing surface profiles of welds before and after grinding. This certainly mandates the deviation from the commonly used surface measurement gauges, which are not only operator dependent, but also limited to discrete measurements along the weld. Due to its potential accuracy and speed, the use of laser-based vision surface profiling systems have been progressively rising as part of manufacturing quality control. This effort presents a virtual environment that lends itself for developing and evaluating existing laser vision sensor (LVS) calibration and measurement techniques. A combination of two known calibration techniques is implemented to deliver a calibrated LVS system. System calibration is implemented virtually and experimentally to scan simulated and 3D printed features of known profiles, respectively. Scanned data is inverted and compared with the input profiles to validate the virtual environment capability for LVS surface profiling and preliminary assess the measurement technique for weld profiling applications. Moreover, this effort brings 3D scanning capability a step closer towards robust quality control applications in a manufacturing environment.

  17. Observations of the Nocturnal Boundary Layer and Morning Transitional Periods in Houston, Texas during the TexAQS II Campaign

    NASA Astrophysics Data System (ADS)

    Day, B. M.; Clements, C. B.; Rappenglueck, B.

    2007-12-01

    High-temporal resolution tethersonde profiles taken during the TexAQS II field campaign in Houston were used to study the overnight development and progression of the nocturnal boundary layer (NBL) and the evolution of the convective boundary layer after sunrise. The measurements were made at the University of Houston campus, located approximately 4 km southeast of the downtown Houston central business district, and consisted of vertical profiles of potential temperature, water vapor mixing ratio, wind speed, wind direction, and ozone concentration. Profile heights averaged 250 m AGL with a few reaching 400 m AGL. Profiles were taken at approximately 30 min intervals throughout 4 nights during Intensive Observational Periods (IOPs), including both the evening and morning transitional periods. Tethersonde experiments also were performed during several additional morning break-up periods during the campaign. Preliminary results from the overnight experiments of Sept 7-8 and Sept 14-15, 2006 showed different NBL evolutions. Sept 7-8 exhibited a stronger and deeper inversion compared with Sept 14-15 when the inversion was weak with a fairly constant height throughout the night. The Sept 7-8 profiles showed elevated bluff-like structures in the virtual potential temperature profiles between 0300-0400 CDT, indicating neutral stability within the 40-90 m AGL level. And, just before sunrise a neutral layer with constant potential temperature developed between the surface and 75 m AGL reflecting horizontal cold air advection. Further analyses will be presented for other vertical profiles taken during the campaign, including the additional overnight profiles as well as the profiles taken during the morning transition to the convective boundary layer.

  18. Thermal feedback in virtual reality and telerobotic systems

    NASA Technical Reports Server (NTRS)

    Zerkus, Mike; Becker, Bill; Ward, Jon; Halvorsen, Lars

    1994-01-01

    A new concept has been developed that allows temperature to be part of the virtual world. The Displaced Temperature Sensing System (DTSS) can 'display' temperature in a virtual reality system.The DTSS can also serve as a feedback device for telerobotics. For virtual reality applications the virtual world software would be required to have a temperature map of its world. By whatever means (magnetic tracker, ultrasound tracker, etc.) the hand and fingers, which have been instrumented with thermodes, would be tracked. The temperature associated with the current position would be transmitted to the DRSS via a serial data link. The DTSS would provide that temperature to the fingers. For telerobotic operation the function of the DTSS is to transmit a temperature from a remote location to the fingers where the temperature can be felt.

  19. Power control of SAFE reactor using fuzzy logic

    NASA Astrophysics Data System (ADS)

    Irvine, Claude

    2002-01-01

    Controlling the 100 kW SAFE (Safe Affordable Fission Engine) reactor consists of design and implementation of a fuzzy logic process control system to regulate dynamic variables related to nuclear system power. The first phase of development concentrates primarily on system power startup and regulation, maintaining core temperature equilibrium, and power profile matching. This paper discusses the experimental work performed in those areas. Nuclear core power from the fuel elements is simulated using resistive heating elements while heat rejection is processed by a series of heat pipes. Both axial and radial nuclear power distributions are determined from neuronic modeling codes. The axial temperature profile of the simulated core is matched to the nuclear power profile by varying the resistance of the heating elements. The SAFE model establishes radial temperature profile equivalence by establishing 32 control zones as the nodal coordinates. Control features also allow for slow warm up, since complete shutoff can occur in the heat pipes if heat-source temperatures drop/rise below a certain minimum value, depending on the specific fluid and gas combination in the heat pipe. The entire system is expected to be self-adaptive, i.e., capable of responding to long-range changes in the space environment. Particular attention in the development of the fuzzy logic algorithm shall ensure that the system process remains at set point, virtually eliminating overshoot on start-up and during in-process disturbances. The controller design will withstand harsh environments and applications where it might come in contact with water, corrosive chemicals, radiation fields, etc. .

  20. Leaky electronic states for photovoltaic photodetectors based on asymmetric superlattices

    NASA Astrophysics Data System (ADS)

    Penello, Germano Maioli; Pereira, Pedro Henrique; Pires, Mauricio Pamplona; Sivco, Deborah; Gmachl, Claire; Souza, Patricia Lustoza

    2018-01-01

    The concept of leaky electronic states in the continuum is used to achieve room temperature operation of photovoltaic superlattice infrared photodetectors. A structural asymmetric InGaAs/InAlAs potential profile is designed to create states in the continuum with the preferential direction for electron extraction and, consequently, to obtain photovoltaic operation at room temperature. Due to the photovoltaic operation and virtual increase in the bandoffset, the device presents both low dark current and low noise. The Johnson noise limited specific detectivity reaches values as high as 1.4 × 1011 Jones at 80 K. At 300 K, the detectivity obtained is 7.0 × 105 Jones.

  1. Visual appearance of a virtual upper limb modulates the temperature of the real hand: a thermal imaging study in Immersive Virtual Reality.

    PubMed

    Tieri, Gaetano; Gioia, Annamaria; Scandola, Michele; Pavone, Enea F; Aglioti, Salvatore M

    2017-05-01

    To explore the link between Sense of Embodiment (SoE) over a virtual hand and physiological regulation of skin temperature, 24 healthy participants were immersed in virtual reality through a Head Mounted Display and had their real limb temperature recorded by means of a high-sensitivity infrared camera. Participants observed a virtual right upper limb (appearing either normally, or with the hand detached from the forearm) or limb-shaped non-corporeal control objects (continuous or discontinuous wooden blocks) from a first-person perspective. Subjective ratings of SoE were collected in each observation condition, as well as temperatures of the right and left hand, wrist and forearm. The observation of these complex, body and body-related virtual scenes resulted in increased real hand temperature when compared to a baseline condition in which a 3d virtual ball was presented. Crucially, observation of non-natural appearances of the virtual limb (discontinuous limb) and limb-shaped non-corporeal objects elicited high increase in real hand temperature and low SoE. In contrast, observation of the full virtual limb caused high SoE and low temperature changes in the real hand with respect to the other conditions. Interestingly, the temperature difference across the different conditions occurred according to a topographic rule that included both hands. Our study sheds new light on the role of an external hand's visual appearance and suggests a tight link between higher-order bodily self-representations and topographic regulation of skin temperature. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  2. The Immersive Virtual Reality Experience: A Typology of Users Revealed Through Multiple Correspondence Analysis Combined with Cluster Analysis Technique.

    PubMed

    Rosa, Pedro J; Morais, Diogo; Gamito, Pedro; Oliveira, Jorge; Saraiva, Tomaz

    2016-03-01

    Immersive virtual reality is thought to be advantageous by leading to higher levels of presence. However, and despite users getting actively involved in immersive three-dimensional virtual environments that incorporate sound and motion, there are individual factors, such as age, video game knowledge, and the predisposition to immersion, that may be associated with the quality of virtual reality experience. Moreover, one particular concern for users engaged in immersive virtual reality environments (VREs) is the possibility of side effects, such as cybersickness. The literature suggests that at least 60% of virtual reality users report having felt symptoms of cybersickness, which reduces the quality of the virtual reality experience. The aim of this study was thus to profile the right user to be involved in a VRE through head-mounted display. To examine which user characteristics are associated with the most effective virtual reality experience (lower cybersickness), a multiple correspondence analysis combined with cluster analysis technique was performed. Results revealed three distinct profiles, showing that the PC gamer profile is more associated with higher levels of virtual reality effectiveness, that is, higher predisposition to be immersed and reduced cybersickness symptoms in the VRE than console gamer and nongamer. These findings can be a useful orientation in clinical practice and future research as they help identify which users are more predisposed to benefit from immersive VREs.

  3. Diagnostic developments for velocity and temperature measurements in uni-element rocket environments

    NASA Astrophysics Data System (ADS)

    Philippart, Kenneth D.

    1995-08-01

    Velocity and temperature measurements were taken within a uni-element rocket combustion chamber for hydrogen-oxygen propellants using laser Doppler velocimetry, thermocouples, and a thermocouple-based temperature rake developed for this effort. Velocity and turbulence profiles were obtained for firings with a gaseous oxygen (GO2)/gaseous hydrogen (GH2) coaxial shear injector at axial locations of 1.6 mm (0.063 in.), 6.4 mm (0.25 in.), 12.7 mm (0.5 in.), 25.4 mm (1 in.) and 50.8 mm (2 in.). Aluminum oxide particles of various sizes seeded the flow in an attempt to explain the discrepancies. While cold-flow simulations were promising, hot-fire results for the various particles were virtually identical and still lower than earlier data. The hot-firings were self-consistent and question the reproducibility of the previous data. Velocity measurements were made closer to the injector than the preceding work. Asymmetries were noted in all profiles. The shear layer displayed high turbulence levels. The central flow near the injector resembled turbulent pipe flow. Recirculation zones existed at the chamber walls and became smaller as the flow evolved downstream. The combusting flow region expanded with increasing axial distance. A thermocouple-instrumented coaxial injector was fired with GO2/GH2 propellants. The injector exit plane boundary conditions were determined. The feasibility of a thermocouple-based temperature rake was established. Tests at three axial positions for air/GM2 firings revealed asymmetric profiles. Temperatures increased with increasing axial distance.

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

    Tierno, S. P., E-mail: sp.tierno@upm.es; Donoso, J. M.; Domenech-Garret, J. L.

    The interaction between an electron emissive wall, electrically biased in a plasma, is revisited through a simple fluid model. We search for realistic conditions of the existence of a non-monotonic plasma potential profile with a virtual cathode as it is observed in several experiments. We mainly focus our attention on thermionic emission related to the operation of emissive probes for plasma diagnostics, although most conclusions also apply to other electron emission processes. An extended Bohm criterion is derived involving the ratio between the two different electron densities at the potential minimum and at the background plasma. The model allows amore » phase-diagram analysis, which confirms the existence of the non-monotonic potential profiles with a virtual cathode. This analysis shows that the formation of the potential well critically depends on the emitted electron current and on the velocity at the sheath edge of cold ions flowing from the bulk plasma. As a consequence, a threshold value of the governing parameter is required, in accordance to the physical nature of the electron emission process. The latter is a threshold wall temperature in the case of thermionic electrons. Experimental evidence supports our numerical calculations of this threshold temperature. Besides this, the potential well becomes deeper with increasing electron emission, retaining a fraction of the released current which limits the extent of the bulk plasma perturbation. This noninvasive property would explain the reliable measurements of plasma potential by using the floating potential method of emissive probes operating in the so-called strong emission regime.« less

  5. FBX aqueous chemical dosimeter for measurement of virtual wedge profiles.

    PubMed

    Semwal, Manoj K; Bansal, Anil K; Thakur, Pradeep K; Vidyasagar, Pandit B

    2008-10-24

    We investigated the ferrous sulfate-benzoic acid-xylenol orange (FBX) aqueous chemical dosimeter for measurement of virtual (dynamic) wedge profiles on a linear accelerator. The layout for irradiation of the FBX-filled tubes mimicked a conventional linear detector array geometry. A comparison of the resulting measurements with film-measured profiles showed that, in the main beam region, the difference between the FBX system and the film system was within +/-2% and that, in the penumbra region, the difference varied from +/-1 mm to +/-2.5 mm in terms of positional equivalence, depending on the size of the dosimeter tubes. We thus believe that the energy-independent FBX dosimetry system can measure virtual wedge profiles with reasonable accuracy at reasonable cost. However, efficiency improvement is required before this dosimetry system can be accepted into routine practice.

  6. Borehole radar interferometry revisited

    USGS Publications Warehouse

    Liu, Lanbo; Ma, Chunguang; Lane, John W.; Joesten, Peter K.

    2014-01-01

    Single-hole, multi-offset borehole-radar reflection (SHMOR) is an effective technique for fracture detection. However, commercial radar system limitations hinder the acquisition of multi-offset reflection data in a single borehole. Transforming cross-hole transmission mode radar data to virtual single-hole, multi-offset reflection data using a wave interferometric virtual source (WIVS) approach has been proposed but not fully demonstrated. In this study, we compare WIVS-derived virtual single-hole, multi-offset reflection data to real SHMOR radar reflection profiles using cross-hole and single-hole radar data acquired in two boreholes located at the University of Connecticut (Storrs, CT USA). The field data results are similar to full-waveform numerical simulations developed for a two-borehole model. The reflection from the adjacent borehole is clearly imaged by both the real and WIVS-derived virtual reflection profiles. Reflector travel-time changes induced by deviation of the two boreholes from the vertical can also be observed on the real and virtual reflection profiles. The results of this study demonstrate the potential of the WIVS approach to improve bedrock fracture imaging for hydrogeological and petroleum reservoir development applications.

  7. Core body temperature control by total liquid ventilation using a virtual lung temperature sensor.

    PubMed

    Nadeau, Mathieu; Micheau, Philippe; Robert, Raymond; Avoine, Olivier; Tissier, Renaud; Germim, Pamela Samanta; Vandamme, Jonathan; Praud, Jean-Paul; Walti, Herve

    2014-12-01

    In total liquid ventilation (TLV), the lungs are filled with a breathable liquid perfluorocarbon (PFC) while a liquid ventilator ensures proper gas exchange by renewal of a tidal volume of oxygenated and temperature-controlled PFC. Given the rapid changes in core body temperature generated by TLV using the lung has a heat exchanger, it is crucial to have accurate and reliable core body temperature monitoring and control. This study presents the design of a virtual lung temperature sensor to control core temperature. In the first step, the virtual sensor, using expired PFC to estimate lung temperature noninvasively, was validated both in vitro and in vivo. The virtual lung temperature was then used to rapidly and automatically control core temperature. Experimentations were performed using the Inolivent-5.0 liquid ventilator with a feedback controller to modulate inspired PFC temperature thereby controlling lung temperature. The in vivo experimental protocol was conducted on seven newborn lambs instrumented with temperature sensors at the femoral artery, pulmonary artery, oesophagus, right ear drum, and rectum. After stabilization in conventional mechanical ventilation, TLV was initiated with fast hypothermia induction, followed by slow posthypothermic rewarming for 1 h, then by fast rewarming to normothermia and finally a second fast hypothermia induction phase. Results showed that the virtual lung temperature was able to provide an accurate estimation of systemic arterial temperature. Results also demonstrate that TLV can precisely control core body temperature and can be favorably compared to extracorporeal circulation in terms of speed.

  8. Realistic natural atmospheric phenomena and weather effects for interactive virtual environments

    NASA Astrophysics Data System (ADS)

    McLoughlin, Leigh

    Clouds and the weather are important aspects of any natural outdoor scene, but existing dynamic techniques within computer graphics only offer the simplest of cloud representations. The problem that this work looks to address is how to provide a means of simulating clouds and weather features such as precipitation, that are suitable for virtual environments. Techniques for cloud simulation are available within the area of meteorology, but numerical weather prediction systems are computationally expensive, give more numerical accuracy than we require for graphics and are restricted to the laws of physics. Within computer graphics, we often need to direct and adjust physical features or to bend reality to meet artistic goals, which is a key difference between the subjects of computer graphics and physical science. Pure physically-based simulations, however, evolve their solutions according to pre-set rules and are notoriously difficult to control. The challenge then is for the solution to be computationally lightweight and able to be directed in some measure while at the same time producing believable results. This work presents a lightweight physically-based cloud simulation scheme that simulates the dynamic properties of cloud formation and weather effects. The system simulates water vapour, cloud water, cloud ice, rain, snow and hail. The water model incorporates control parameters and the cloud model uses an arbitrary vertical temperature profile, with a tool described to allow the user to define this. The result of this work is that clouds can now be simulated in near real-time complete with precipitation. The temperature profile and tool then provide a means of directing the resulting formation..

  9. A Virtual Rat for Simulating Environmental and Exertional Heat Stress

    DTIC Science & Technology

    2014-10-02

    unsuitable for accurately determin- ing the spatiotemporal temperature distribution in the animal due to heat stress and for performing mechanistic analysis ...possible in the original experiments. Finally, we performed additional simu- lations using the virtual rat to facilitate comparative analysis of the...capability of the virtual rat to account for the circadian rhythmicity in core temperatures during an in- crease in the external temperature from 22

  10. Simulation of the impact of refractive surgery ablative laser pulses with a flying-spot laser beam on intrasurgery corneal temperature.

    PubMed

    Shraiki, Mario; Arba-Mosquera, Samuel

    2011-06-01

    To evaluate ablation algorithms and temperature changes in laser refractive surgery. The model (virtual laser system [VLS]) simulates different physical effects of an entire surgical process, simulating the shot-by-shot ablation process based on a modeled beam profile. The model is comprehensive and directly considers applied correction; corneal geometry, including astigmatism; laser beam characteristics; and ablative spot properties. Pulse lists collected from actual treatments were used to simulate the temperature increase during the ablation process. Ablation efficiency reduction in the periphery resulted in a lower peripheral temperature increase. Steep corneas had lesser temperature increases than flat ones. The maximum rise in temperature depends on the spatial density of the ablation pulses. For the same number of ablative pulses, myopic corrections showed the highest temperature increase, followed by myopic astigmatism, mixed astigmatism, phototherapeutic keratectomy (PTK), hyperopic astigmatism, and hyperopic treatments. The proposed model can be used, at relatively low cost, for calibration, verification, and validation of the laser systems used for ablation processes and would directly improve the quality of the results.

  11. A ranking method for the concurrent learning of compounds with various activity profiles.

    PubMed

    Dörr, Alexander; Rosenbaum, Lars; Zell, Andreas

    2015-01-01

    In this study, we present a SVM-based ranking algorithm for the concurrent learning of compounds with different activity profiles and their varying prioritization. To this end, a specific labeling of each compound was elaborated in order to infer virtual screening models against multiple targets. We compared the method with several state-of-the-art SVM classification techniques that are capable of inferring multi-target screening models on three chemical data sets (cytochrome P450s, dehydrogenases, and a trypsin-like protease data set) containing three different biological targets each. The experiments show that ranking-based algorithms show an increased performance for single- and multi-target virtual screening. Moreover, compounds that do not completely fulfill the desired activity profile are still ranked higher than decoys or compounds with an entirely undesired profile, compared to other multi-target SVM methods. SVM-based ranking methods constitute a valuable approach for virtual screening in multi-target drug design. The utilization of such methods is most helpful when dealing with compounds with various activity profiles and the finding of many ligands with an already perfectly matching activity profile is not to be expected.

  12. Using Virtual Reality to Characterize Episodic Memory Profiles in Amnestic Mild Cognitive Impairment and Alzheimer's Disease: Influence of Active and Passive Encoding

    ERIC Educational Resources Information Center

    Plancher, G.; Tirard, A.; Gyselinck, V.; Nicolas, S.; Piolino, P.

    2012-01-01

    Most neuropsychological assessments of episodic memory bear little similarity to the events that patients actually experience as memories in daily life. The first aim of this study was to use a virtual environment to characterize episodic memory profiles in an ecological fashion, which includes memory for central and perceptual details,…

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

    Zhang, J; Li, X; Ding, X

    Purpose: We investigate the spot characteristic and dose profiles properties from a compact gantry proton therapy system. This compact design features a dedicated pencil beam scanning nozzle with the scanning magnet located upstream of the final 60 degree bending magnet. Due to the unique beam line design, uncertainty has been raised in the virtual source-to-axis distance (SAD). We investigate its potential clinical impact through measurements and simulation. Methods: A scintillator camera based detector was used to measure spot characteristics and position accuracy. An ion chamber array device was used to measure planar dose profile. Dose profile in-air simulation was performedmore » using in-house built MATLAB program based on additional spot parameters directly from measurements. Spot characteristics such as position and in-air sigma values were used to general simulated 2D elliptical Gaussian spots. The virtual SAD distance changes in the longitudinal direction were also simulated. Planar dose profiles were generated by summation of simulated spots at the isocenter, 15 cm above the isocenter, and 15 cm below the isocenter for evaluation of potential clinical dosimetric impact. Results: We found that the virtual SAD varies depending on the spot location on the longitudinal axis. Measurements have shown that the variable SAD changes from 7 to 12 meters from one end to the other end of the treatment field in the longitudinal direction. The simulation shows that the planer dose profiles differences between the fixed SAD and variable SAD are within 3% from the isocenter profile and the lateral penumbras are within 1 mm difference. Conclusion: Our measurements and simulations show that there are minimum effects on the spot characteristics and dose profiles for this up-stream scanning compact system proton system. Further treatment planning study is needed with the variable virtual SAD accounted for in the planning system to show minimum dosimetric impact.« less

  14. Low body temperature does not compromise the treatment effect of alteplase.

    PubMed

    Lees, Jennifer S; Mishra, Nishant K; Saini, Monica; Lyden, Patrick D; Shuaib, Ashfaq

    2011-09-01

    Hypothermia is neuroprotective in ischemic stroke models. The influence of baseline body temperature on outcomes after thrombolytic therapy is unclear. We examined outcomes after alteplase treatment across baseline body temperature for patients with ischemic stroke in data held within the Virtual International Stroke Trials Archive (VISTA; 1998 to 2007). We collated data on age, baseline severity (National Institutes of Health Stroke Scale), and 90-day modified Rankin Scale score on patients presenting with acute ischemic stroke. We compared 90-day modified Rankin Scale score between thrombolyzed and nonthrombolyzed comparators across baseline body temperature. We report age and baseline National Institutes of Health Stroke Scale-adjusted Cochran-Mantel-Haenszel probability value and proportional OR with 95% CI for improved modified Rankin Scale distribution. We report temperature profiles over 72 hours after stroke by treatment group. Rankin data were available for 5586 patients with acute ischemic stroke in VISTA (1980 received alteplase). Age and baseline severity were similar (age 68.0±13.0 years versus 69.9±12.3 years, National Institutes of Health Stroke Scale 14.2±5.2 versus 13.0±5.6). Alteplase was associated with improved outcome (OR, 1.49; 95% CI, 1.35 to 1.65, P<0.0001). Alteplase treatment effect was not associated with baseline temperature (P=0.14). Point estimates showed benefit of alteplase treatment across 35.5°C to 37.5°C but showed a negative trend >37.5°C. Alteplase did not influence temperature profiles over 72 hours after stroke. There is no evidence of influence of body temperature on alteplase treatment response. These results are reassuring that low temperatures across a physiological range do not compromise therapeutic effect of alteplase.

  15. Energy management using virtual reality improves 2000-m rowing performance.

    PubMed

    Hoffmann, Charles P; Filippeschi, Alessandro; Ruffaldi, Emanuele; Bardy, Benoit G

    2014-01-01

    Elite-standard rowers tend to use a fast-start strategy followed by an inverted parabolic-shaped speed profile in 2000-m races. This strategy is probably the best to manage energy resources during the race and maximise performance. This study investigated the use of virtual reality (VR) with novice rowers as a means to learn about energy management. Participants from an avatar group (n = 7) were instructed to track a virtual boat on a screen, whose speed was set individually to follow the appropriate to-be-learned speed profile. A control group (n = 8) followed an indoor training programme. In spite of similar physiological characteristics in the groups, the avatar group learned and maintained the required profile, resulting in an improved performance (i.e. a decrease in race duration), whereas the control group did not. These results suggest that VR is a means to learn an energy-related skill and improve performance.

  16. Jack'd, a Mobile Social Networking Application: A Site of Exclusion Within a Site of Inclusion.

    PubMed

    Bartone, Michael D

    2018-01-01

    User-generated smartphone applications have created a new level of virtual connectivity for gay males, one in which users can create profiles and meet other users as nearby or as far away as possible. For those within close proximity, the other users can be considered their "virtual neighbors." Although the applications are theoretically designed to be places of inclusion and not exclusion, where any gay male with economic means can download an application, many profiles have been created that exclude other users. Through an examination of profiles on one such application, Jack'd, exclusion is found in the way users celebrate and reinforce ideas of traditional masculinity and denigrate and reinforce stereotypic ideas of femininity embodied by some gay men. Jack'd, and other user-generated smartphone applications, can be read as virtual neighborhoods where one is excluded based on their gender performance.

  17. SRM 2460/2461 Standard Bullets and Casings Project

    PubMed Central

    Song, J.; Whitenton, E.; Kelley, D.; Clary, R.; Ma, L.; Ballou, S.; Ols, M.

    2004-01-01

    The National Institute of Standards and Technology Standard Reference Material (SRM) 2460/2461 standard bullets and casings project will provide support to firearms examiners and to the National Integrated Ballistics Information Network (NIBIN) in the United States. The SRM bullet is designed as both a virtual and a physical bullet profile signature standard. The virtual standard is a set of six digitized bullet profile signatures originally traced from six master bullets fired at the Bureau of Alcohol, Tobacco and Firearms (ATF) and the Federal Bureau of Investigation (FBI). By using the virtual signature standard to control the tool path on a numerically controlled diamond turning machine, 40 SRM bullets were produced. A profile signature measurement system was established for the SRM bullets. The profile signature differences are quantified by the maximum of the cross correlation function and by the signature difference between pairs of compared profile signatures measured on different SRM bullets. Initial measurement results showed high reproducibility for both the measurement system and production process of the SRM bullets. A traceability scheme has been proposed to establish the measurement traceability for nationwide bullet signature measurements to NIST, ATF and FBI. Prototype SRM casings have also been developed. PMID:27366632

  18. Development and application of a ray-tracing code integrating with 3D equilibrium mapping in LHD ECH experiments

    NASA Astrophysics Data System (ADS)

    Tsujimura, T., Ii; Kubo, S.; Takahashi, H.; Makino, R.; Seki, R.; Yoshimura, Y.; Igami, H.; Shimozuma, T.; Ida, K.; Suzuki, C.; Emoto, M.; Yokoyama, M.; Kobayashi, T.; Moon, C.; Nagaoka, K.; Osakabe, M.; Kobayashi, S.; Ito, S.; Mizuno, Y.; Okada, K.; Ejiri, A.; Mutoh, T.

    2015-11-01

    The central electron temperature has successfully reached up to 7.5 keV in large helical device (LHD) plasmas with a central high-ion temperature of 5 keV and a central electron density of 1.3× {{10}19} m-3. This result was obtained by heating with a newly-installed 154 GHz gyrotron and also the optimisation of injection geometry in electron cyclotron heating (ECH). The optimisation was carried out by using the ray-tracing code ‘LHDGauss’, which was upgraded to include the rapid post-processing three-dimensional (3D) equilibrium mapping obtained from experiments. For ray-tracing calculations, LHDGauss can automatically read the relevant data registered in the LHD database after a discharge, such as ECH injection settings (e.g. Gaussian beam parameters, target positions, polarisation and ECH power) and Thomson scattering diagnostic data along with the 3D equilibrium mapping data. The equilibrium map of the electron density and temperature profiles are then extrapolated into the region outside the last closed flux surface. Mode purity, or the ratio between the ordinary mode and the extraordinary mode, is obtained by calculating the 1D full-wave equation along the direction of the rays from the antenna to the absorption target point. Using the virtual magnetic flux surfaces, the effects of the modelled density profiles and the magnetic shear at the peripheral region with a given polarisation are taken into account. Power deposition profiles calculated for each Thomson scattering measurement timing are registered in the LHD database. The adjustment of the injection settings for the desired deposition profile from the feedback provided on a shot-by-shot basis resulted in an effective experimental procedure.

  19. Insect eggs protected from high temperatures by limited homeothermy of plant leaves.

    PubMed

    Potter, Kristen; Davidowitz, Goggy; Woods, H Arthur

    2009-11-01

    Virtually all aspects of insect biology are affected by body temperature, and many taxa have evolved sophisticated temperature-control mechanisms. All insects, however, begin life as eggs and lack the ability to thermoregulate. Eggs laid on leaves experience a thermal environment, and thus a body temperature, that is strongly influenced by the leaves themselves. Because plants can maintain leaf temperatures that differ from ambient, e.g. by evapotranspiration, plant hosts may protect eggs from extreme ambient temperatures. We examined the degree to which leaves buffer ambient thermal variation and whether that buffering benefits leaf-associated insect eggs. In particular, we: (1) measured temperature variation at oviposition sites in the field, (2) manipulated temperatures in the laboratory to determine the effect of different thermal conditions on embryo development time and survival, and (3) tested embryonic metabolic rates over increasing temperatures. Our results show that Datura wrightii leaves buffer Manduca sexta eggs from fatally high ambient temperatures in the southwestern USA. Moreover, small differences in temperature profiles among leaves can cause large variation in egg metabolic rate and development time. Specifically, large leaves were hotter than small leaves during the day, reaching temperatures that are stressfully high for eggs. This study provides the first mechanistic demonstration of how this type of leaf-constructed thermal refuge interacts with egg physiology.

  20. Obtaining Potential Virtual Temperature Profiles, Entrainment Fluxes, and Spectra from Mini Unmanned Aerial Vehicle Data

    NASA Astrophysics Data System (ADS)

    Dias, N. L.; Gonçalves, J. E.; Freire, L. S.; Hasegawa, T.; Malheiros, A. L.

    2012-10-01

    We present a simple but effective small unmanned aerial vehicle design that is able to make high-resolution temperature and humidity measurements of the atmospheric boundary layer. The air model used is an adapted commercial design, and is able to carry all the instrumentation (barometer, temperature and humidity sensor, and datalogger) required for such measurements. It is fitted with an autopilot that controls the plane's ascent and descent in a spiral to 1800 m above ground. We describe the results obtained on three different days when the plane, called Aerolemma-3, flew continuously throughout the day. Surface measurements of the sensible virtual heat flux made simultaneously allowed the calculation of all standard convective turbulence scales for the boundary layer, as well as a rigorous test of existing models for the entrainment flux at the top of the boundary layer, and for its growth. A novel approach to calculate the entrainment flux from the top-down, bottom-up model of Wynagaard and Brost is used. We also calculated temperature fluctuations by means of a spectral high-pass filter, and calculated their spectra. Although the time series are small, tapering proved ineffective in this case. The spectra from the untapered series displayed a consistent -5/3 behaviour, and from them it was possible to calculate a dimensionless dissipation function, which exhibited the expected similarity behaviour against boundary-layer bulk stability. The simplicity, ease of use and economy of such small aircraft make us optimistic about their usefulness in boundary-layer research.

  1. Modelling Cerebral Blood Flow and Temperature Using a Vascular Porous Model

    NASA Astrophysics Data System (ADS)

    Blowers, Stephen; Thrippleton, Michael; Marshall, Ian; Harris, Bridget; Andrews, Peter; Valluri, Prashant

    2016-11-01

    Macro-modelling of cerebral blood flow can assist in determining the impact of temperature intervention to reduce permanent tissue damage during instances of brain trauma. Here we present a 3D two phase fluid-porous model for simulating blood flow through the capillary region linked to intersecting 1D arterial and venous vessel trees. This combined vasculature porous (VaPor) model simulates both flow and energy balances, including heat from metabolism, using a vasculature extracted from MRI data which are expanded upon using a tree generation algorithm. Validation of temperature balance has been achieved using rodent brain data. Direct flow validation is not as straight forward due to the method used in determining regional cerebral blood flow (rCBF). In-vivo measurements are achieved using a tracer, which disagree with direct measurements of simulated flow. However, by modelling a virtual tracer, rCBF values are obtained that agree with those found in literature. Temperature profiles generated with the VaPor model show a reduction in core brain temperature after cooling the scalp not seen previously in other models.

  2. The relationship between virtual body ownership and temperature sensitivity

    PubMed Central

    Llobera, Joan; Sanchez-Vives, M. V.; Slater, Mel

    2013-01-01

    In the rubber hand illusion, tactile stimulation seen on a rubber hand, that is synchronous with tactile stimulation felt on the hidden real hand, can lead to an illusion of ownership over the rubber hand. This illusion has been shown to produce a temperature decrease in the hidden hand, suggesting that such illusory ownership produces disownership of the real hand. Here, we apply immersive virtual reality (VR) to experimentally investigate this with respect to sensitivity to temperature change. Forty participants experienced immersion in a VR with a virtual body (VB) seen from a first-person perspective. For half the participants, the VB was consistent in posture and movement with their own body, and in the other half, there was inconsistency. Temperature sensitivity on the palm of the hand was measured before and during the virtual experience. The results show that temperature sensitivity decreased in the consistent compared with the inconsistent condition. Moreover, the change in sensitivity was significantly correlated with the subjective illusion of virtual arm ownership but modulated by the illusion of ownership over the full VB. This suggests that a full body ownership illusion results in a unification of the virtual and real bodies into one overall entity—with proprioception and tactile sensations on the real body integrated with the visual presence of the VB. The results are interpreted in the framework of a ‘body matrix’ recently introduced into the literature. PMID:23720537

  3. Virtual gonio-spectrophotometer for validation of BRDF designs

    NASA Astrophysics Data System (ADS)

    Mihálik, Andrej; Ďurikovič, Roman

    2011-10-01

    Measurement of the appearance of an object consists of a group of measurements to characterize the color and surface finish of the object. This group of measurements involves the spectral energy distribution of propagated light measured in terms of reflectance and transmittance, and the spatial energy distribution of that light measured in terms of the bidirectional reflectance distribution function (BRDF). In this article we present the virtual gonio-spectrophotometer, a device that measures flux (power) as a function of illumination and observation. Virtual gonio-spectrophotometer measurements allow the determination of the scattering profile of specimens that can be used to verify the physical characteristics of the computer model used to simulate the scattering profile. Among the characteristics that we verify is the energy conservation of the computer model. A virtual gonio-spectrophotometer is utilized to find the correspondence between industrial measurements obtained from gloss meters and the parameters of a computer reflectance model.

  4. Analysis of the social network development of a virtual community for Australian intensive care professionals.

    PubMed

    Rolls, Kaye Denise; Hansen, Margaret; Jackson, Debra; Elliott, Doug

    2014-11-01

    Social media platforms can create virtual communities, enabling healthcare professionals to network with a broad range of colleagues and facilitate knowledge exchange. In 2003, an Australian state health department established an intensive care mailing list to address the professional isolation experienced by senior intensive care nurses. This article describes the social network created within this virtual community by examining how the membership profile evolved from 2003 to 2009. A retrospective descriptive design was used. The data source was a deidentified member database. Since 2003, 1340 healthcare professionals subscribed to the virtual community with 78% of these (n = 1042) still members at the end of 2009. The membership profile has evolved from a single-state nurse-specific network to an Australia-wide multidisciplinary and multiorganizational intensive care network. The uptake and retention of membership by intensive care clinicians indicated that they appeared to value involvement in this virtual community. For healthcare organizations, a virtual community may be a communications option for minimizing professional and organizational barriers and promoting knowledge flow. Further research is, however, required to demonstrate a link between these broader social networks, enabling the exchange of knowledge and improved patient outcomes.

  5. Human intestinal transporter database: QSAR modeling and virtual profiling of drug uptake, efflux and interactions.

    PubMed

    Sedykh, Alexander; Fourches, Denis; Duan, Jianmin; Hucke, Oliver; Garneau, Michel; Zhu, Hao; Bonneau, Pierre; Tropsha, Alexander

    2013-04-01

    Membrane transporters mediate many biological effects of chemicals and play a major role in pharmacokinetics and drug resistance. The selection of viable drug candidates among biologically active compounds requires the assessment of their transporter interaction profiles. Using public sources, we have assembled and curated the largest, to our knowledge, human intestinal transporter database (>5,000 interaction entries for >3,700 molecules). This data was used to develop thoroughly validated classification Quantitative Structure-Activity Relationship (QSAR) models of transport and/or inhibition of several major transporters including MDR1, BCRP, MRP1-4, PEPT1, ASBT, OATP2B1, OCT1, and MCT1. QSAR models have been developed with advanced machine learning techniques such as Support Vector Machines, Random Forest, and k Nearest Neighbors using Dragon and MOE chemical descriptors. These models afforded high external prediction accuracies of 71-100% estimated by 5-fold external validation, and showed hit retrieval rates with up to 20-fold enrichment in the virtual screening of DrugBank compounds. The compendium of predictive QSAR models developed in this study can be used for virtual profiling of drug candidates and/or environmental agents with the optimal transporter profiles.

  6. The diffusion of water in haploanesite

    NASA Astrophysics Data System (ADS)

    Ni, H.; Zhang, Y.

    2008-12-01

    Diffusive transport of water in silicate melts is a key process in magma dynamics and volcanic eruptions, including bubble growth. Previous studies demonstrate that in additional to temperature, water content and pressure, melt composition also plays an important role in determining water diffusivity. We carried out high temperature (1311-1512°C) diffusion-couple experiments and intermediate temperature (470- 600°C) dehydration experiments to investigate H2O diffusion in a melt of haploandesitic composition. The diffusion couple is composed of an anhydrous (with <0.1 wt.% H2O) and a hydrous (with 2 wt.% H2O) haploandesitic glass. A platinum capsule is used to contain the couple and then it is welded shut. Diffusion runs are carried out in a 12.7-mm piston-cylinder apparatus at 1 GPa and superliquidus temperatures of 1584-1785 K. Infrared microscopy is applied on quenched glass to measure the profile of total H2O concentration (H2Ot). The profile shape is best fit by an error function, indicating an H2O diffusivity virtually independent of H2O concentration, consistent with the results of Behrens et al. (2004) on an Fe-bearing andesite. Dehydration experiments are performed at 743-873 K in a rapid-quench cold-seal vessel, with a heated hydrous glass losing water to 0.1 GPa Ar atmosphere. Measured diffusion profiles, however, show that water diffusivity is dependent on water content. Experimental data can be explained by H2Om being the dominating diffusant or a total H2O diffusivity proportional to total H2O content. The distinction between the high-temperature experiments where H2Ot diffusivity is apparently independent of H2Ot content, and the intermediate-temperature experiments where H2Ot diffusivity depends on H2Ot can be rationalized if OH diffusion has a higher activation energy than molecular H2O diffusion, and their comparable diffusivities at high T gradually diverge as temperature is lowered. At below 1 wt.% H2O, water diffusivity increases from rhyolite to dacite to andesite at >1300°C, and this sequence is reversed at <600°C.

  7. Application of FLEET Velocimetry in the NASA Langley 0.3-meter Transonic Cryogenic Tunnel

    NASA Technical Reports Server (NTRS)

    Burns, Ross A.; Danehy, Paul M.; Halls, Benjamin R.; Jiang, Naibo

    2015-01-01

    Femtosecond laser electronic excitation and tagging (FLEET) velocimetry is demonstrated in a large-scale transonic cryogenic wind tunnel. Test conditions include total pressures, total temperatures, and Mach numbers ranging from 15 to 58 psia, 200 to 295 K, and 0.2 to 0.75, respectively. Freestream velocity measurements exhibit accuracies within 1 percent and precisions better than 1 m/s. The measured velocities adhere closely to isentropic flow theory over the domain of temperatures and pressures that were tested. Additional velocity measurements are made within the tunnel boundary layer; virtual trajectories traced out by the FLEET signal are indicative of the characteristic turbulent behavior in this region of the flow, where the unsteadiness increases demonstrably as the wall is approached. Mean velocities taken within the boundary layer are in agreement with theoretical velocity profiles, though the fluctuating velocities exhibit a greater deviation from theoretical predictions.

  8. A virtual remote sensing observation network for continuous, near-real-time monitoring of atmospheric instability

    NASA Astrophysics Data System (ADS)

    Toporov, Maria; Löhnert, Ulrich; Potthast, Roland; Cimini, Domenico; De Angelis, Francesco

    2017-04-01

    Short-term forecasts of current high-resolution numerical weather prediction models still have large deficits in forecasting the exact temporal and spatial location of severe, locally influenced weather such as summer-time convective storms or cool season lifted stratus or ground fog. Often, the thermodynamic instability - especially in the boundary layer - plays an essential role in the evolution of weather events. While the thermodynamic state of the atmosphere is well measured close to the surface (i.e. 2 m) by in-situ sensors and in the upper troposphere by satellite sounders, the planetary boundary layer remains a largely under-sampled region of the atmosphere where only sporadic information from radiosondes or aircraft observations is available. The major objective of the presented DWD-funded project ARON (Extramural Research Programme) is to overcome this observational gap and to design an optimized network of ground based microwave radiometers (MWR) and compact Differential Absorption Lidars (DIAL) for a continuous, near-real-time monitoring of temperature and humidity in the atmospheric boundary layer in order to monitor thermodynamic (in)stability. Previous studies showed, that microwave profilers are well suited for continuously monitoring the temporal development of atmospheric stability (i.e. Cimini et al., 2015) before the initiation of deep convection, especially in the atmospheric boundary layer. However, the vertical resolution of microwave temperature profiles is best in the lowest kilometer above the surface, decreasing rapidly with increasing height. In addition, humidity profile retrievals typically cannot be resolved with more than two degrees of freedom for signal, resulting in a rather poor vertical resolution throughout the troposphere. Typical stability indices used to assess the potential of convection rely on temperature and humidity values not only in the region of the boundary layer but also in the layers above. Therefore, satellite remote sensing (i.e. SEVIRI, AMSU) is used to complement observations from a virtual ground-based microwave radiometer network based on the reanalysis of the COSMO model for Europe. In this contribution, we present a synergetic retrieval algorithm of stability indices from satellite observations and ground-based microwave measurements based on the COSMO-DE reanalysis as truth. In order to make the approach feasible for data assimilation applications at national weather services, we simulate satellite observations with the standard RTTOV model and use the newly developed RTTOV-gb (ground-based) for the ground-based radiometers (De Angelis et al., 2016). For the detection of significant instabilities, we show the synergy benefit in terms of uncertainty reduction, probability of detection and other forecast skill scores. The overall goal of ARON is to quantify the impact of ground-based vertical profilers within an integrated forecasting system, which combines short-term and now-casting.

  9. Artificial intelligence in public health prevention of legionelosis in drinking water systems.

    PubMed

    Sinčak, Peter; Ondo, Jaroslav; Kaposztasova, Daniela; Virčikova, Maria; Vranayova, Zuzana; Sabol, Jakub

    2014-08-21

    Good quality water supplies and safe sanitation in urban areas are a big challenge for governments throughout the world. Providing adequate water quality is a basic requirement for our lives. The colony forming units of the bacterium Legionella pneumophila in potable water represent a big problem which cannot be overlooked for health protection reasons. We analysed several methods to program a virtual hot water tank with AI (artificial intelligence) tools including neuro-fuzzy systems as a precaution against legionelosis. The main goal of this paper is to present research which simulates the temperature profile in the water tank. This research presents a tool for a water management system to simulate conditions which are able to prevent legionelosis outbreaks in a water system. The challenge is to create a virtual water tank simulator including the water environment which can simulate a situation which is common in building water distribution systems. The key feature of the presented system is its adaptation to any hot water tank. While respecting the basic parameters of hot water, a water supplier and building maintainer are required to ensure the predefined quality and water temperature at each sampling site and avoid the growth of Legionella. The presented system is one small contribution how to overcome a situation when legionelosis could find good conditions to spread and jeopardize human lives.

  10. Artificial Intelligence in Public Health Prevention of Legionelosis in Drinking Water Systems

    PubMed Central

    Sinčak, Peter; Ondo, Jaroslav; Kaposztasova, Daniela; Virčikova, Maria; Vranayova, Zuzana; Sabol, Jakub

    2014-01-01

    Good quality water supplies and safe sanitation in urban areas are a big challenge for governments throughout the world. Providing adequate water quality is a basic requirement for our lives. The colony forming units of the bacterium Legionella pneumophila in potable water represent a big problem which cannot be overlooked for health protection reasons. We analysed several methods to program a virtual hot water tank with AI (artificial intelligence) tools including neuro-fuzzy systems as a precaution against legionelosis. The main goal of this paper is to present research which simulates the temperature profile in the water tank. This research presents a tool for a water management system to simulate conditions which are able to prevent legionelosis outbreaks in a water system. The challenge is to create a virtual water tank simulator including the water environment which can simulate a situation which is common in building water distribution systems. The key feature of the presented system is its adaptation to any hot water tank. While respecting the basic parameters of hot water, a water supplier and building maintainer are required to ensure the predefined quality and water temperature at each sampling site and avoid the growth of Legionella. The presented system is one small contribution how to overcome a situation when legionelosis could find good conditions to spread and jeopardize human lives. PMID:25153475

  11. High frequency longitudinal profiling reveals hydrologic controls on solute sourcing, transport and processing in a karst river

    NASA Astrophysics Data System (ADS)

    Hensley, R. T.; Cohen, M. J.; Spangler, M.; Gooseff, M. N.

    2017-12-01

    The lower Santa Fe River is a large, karst river of north Florida, fed by numerous artesian springs and also containing multiple sink-rise systems. We performed repeated longitudinal profiles collecting very high frequency measurements of multiple stream parameters including temperature, dissolved oxygen, carbon dioxide, pH, dissolved organic matter, nitrate, ammonium, phosphate and turbidity. This high frequency dataset provided a spatially explicit understanding of solute sources and coupled biogeochemical processing rates along the 25 km study reach. We noted marked changes in river profiles as the river transitioned from low to high flow during the onset of the wet season. The role of lateral inflow from springs as the primary solute source was greatly reduced under high flow conditions. Effects of sink-rise systems, which under low flow conditions allow the majority of flow to bypass several kilometer long sections of the main channel, virtually disappeared under high flow conditions. Impeded light transmittance at high flow reduced primary production and by extension assimilatory nutrient uptake. This study demonstrates how high frequency longitudinal profiling can be used to observe how hydrologic conditions can alter groundwater-surface water interactions and modulate the sourcing, transport and biogeochemical processing of stream solutes.

  12. How do cuticular hydrocarbons evolve? Physiological constraints and climatic and biotic selection pressures act on a complex functional trait

    PubMed Central

    Blaimer, Bonnie B.; Schmitt, Thomas

    2017-01-01

    Cuticular hydrocarbons (CHCs) cover the cuticles of virtually all insects, serving as a waterproofing agent and as a communication signal. The causes for the high CHC variation between species, and the factors influencing CHC profiles, are scarcely understood. Here, we compare CHC profiles of ant species from seven biogeographic regions, searching for physiological constraints and for climatic and biotic selection pressures. Molecule length constrained CHC composition: long-chain profiles contained fewer linear alkanes, but more hydrocarbons with disruptive features in the molecule. This is probably owing to selection on the physiology to build a semi-fluid cuticular layer, which is necessary for waterproofing and communication. CHC composition also depended on the precipitation in the ants' habitats. Species from wet climates had more alkenes and fewer dimethyl alkanes than those from drier habitats, which can be explained by different waterproofing capacities of these compounds. By contrast, temperature did not affect CHC composition. Mutualistically associated (parabiotic) species possessed profiles highly distinct from non-associated species. Our study is, to our knowledge, the first to show systematic impacts of physiological, climatic and biotic factors on quantitative CHC composition across a global, multi-species dataset. We demonstrate how they jointly shape CHC profiles, and advance our understanding of the evolution of this complex functional trait in insects. PMID:28298343

  13. Surface-Roughness-Based Virtual Textiles: Evaluation Using a Multi-Contactor Display.

    PubMed

    Philpott, Matthew; Summers, Ian R

    2015-01-01

    Virtual textiles, generated in response to exploratory movements, are presented to the fingertip via a 24-contactor vibrotactile array. Software models are based on surface-roughness profiles from real textiles. Results suggest that distinguishable "textile-like" surfaces are produced, but these lack the necessary accuracy for reliable matching to real textiles.

  14. Repeatability and Reproducibility of Virtual Subjective Refraction.

    PubMed

    Perches, Sara; Collados, M Victoria; Ares, Jorge

    2016-10-01

    To establish the repeatability and reproducibility of a virtual refraction process using simulated retinal images. With simulation software, aberrated images corresponding with each step of the refraction process were calculated following the typical protocol of conventional subjective refraction. Fifty external examiners judged simulated retinal images until the best sphero-cylindrical refraction and the best visual acuity were achieved starting from the aberrometry data of three patients. Data analyses were performed to assess repeatability and reproducibility of the virtual refraction as a function of pupil size and aberrometric profile of different patients. SD values achieved in three components of refraction (M, J0, and J45) are lower than 0.25D in repeatability analysis. Regarding reproducibility, we found SD values lower than 0.25D in the most cases. When the results of virtual refraction with different pupil diameters (4 and 6 mm) were compared, the mean of differences (MoD) obtained were not clinically significant (less than 0.25D). Only one of the aberrometry profiles with high uncorrected astigmatism shows poor results for the M component in reproducibility and pupil size dependence analysis. In all cases, vision achieved was better than 0 logMAR. A comparison between the compensation obtained with virtual and conventional subjective refraction was made as an example of this application, showing good quality retinal images in both processes. The present study shows that virtual refraction has similar levels of precision as conventional subjective refraction. Moreover, virtual refraction has also shown that when high low order astigmatism is present, the refraction result is less precise and highly dependent on pupil size.

  15. Data Quality Assessment Methods for the Eastern Range 915 MHz Wind Profiler Network

    NASA Technical Reports Server (NTRS)

    Lambert, Winifred C.; Taylor, Gregory E.

    1998-01-01

    The Eastern Range installed a network of five 915 MHz Doppler Radar Wind Profilers with Radio Acoustic Sounding Systems in the Cape Canaveral Air Station/Kennedy Space Center area to provide three-dimensional wind speed and direction and virtual temperature estimates in the boundary layer. The Applied Meteorology Unit, staffed by ENSCO, Inc., was tasked by the 45th Weather Squadron, the Spaceflight Meteorology Group, and the National Weather Service in Melbourne, Florida to investigate methods which will help forecasters assess profiler network data quality when developing forecasts and warnings for critical ground, launch and landing operations. Four routines were evaluated in this study: a consensus time period check a precipitation contamination check, a median filter, and the Weber-Wuertz (WW) algorithm. No routine was able to effectively flag suspect data when used by itself. Therefore, the routines were used in different combinations. An evaluation of all possible combinations revealed two that provided the best results. The precipitation contamination and consensus time routines were used in both combinations. The median filter or WW was used as the final routine in the combinations to flag all other suspect data points.

  16. Tomography for two-dimensional gas temperature distribution based on TDLAS

    NASA Astrophysics Data System (ADS)

    Luo, Can; Wang, Yunchu; Xing, Fei

    2018-03-01

    Based on tunable diode laser absorption spectroscopy (TDLAS), the tomography is used to reconstruct the combustion gas temperature distribution. The effects of number of rays, number of grids, and spacing of rays on the temperature reconstruction results for parallel ray are researched. The reconstruction quality is proportional to the ray number. The quality tends to be smoother when the ray number exceeds a certain value. The best quality is achieved when η is between 0.5 and 1. A virtual ray method combined with the reconstruction algorithms is tested. It is found that virtual ray method is effective to improve the accuracy of reconstruction results, compared with the original method. The linear interpolation method and cubic spline interpolation method, are used to improve the calculation accuracy of virtual ray absorption value. According to the calculation results, cubic spline interpolation is better. Moreover, the temperature distribution of a TBCC combustion chamber is used to validate those conclusions.

  17. Factors that predict the use or non-use of virtual dissection by high school biology teachers

    NASA Astrophysics Data System (ADS)

    Cockerham, William

    2001-07-01

    With the advent of computers into scholastic classrooms, virtual dissection has become a potential educational tool in high school biology lab settings. Utilizing non-experimental survey research methodology, this study attempted to identify factors that may influence high school biology teachers to use or not to use a virtual dissection. A 75-item research survey instrument consisting of both demographic background and Likert style questions was completed by 215 high school members of the National Association of Biology Teachers. The survey responses provided data to answer the research questions concerning the relationship between the likelihood of a high school biology teacher using a virtual dissection and a number of independent variables from the following three categories: (a) demographics, (b) attitude and experience, and (c) resources and support. These data also allowed for the determination of a demographic profile of the sample population. The demographic profile showed the sample population of high school biology teachers to be two-thirds female, mature, highly educated and very experienced. Analysis of variance and Pearson product moment correlational statistics were used to determine if there was a relationship between high school biology teachers' likelihood to use a virtual dissection and the independent variables. None of the demographic or resource and support independent variables demonstrated a strong relationship to the dependent variable of teachers' likelihood to use a virtual dissection. Three of the attitude and experience independent variables showed a statistically significant (p < .05) relationship to teachers' likelihood to use a virtual dissection: attitude toward virtual dissection, previous use of a virtual dissection and intention to use a real animal dissection. These findings may indicate that teachers are using virtual dissection as a supplement rather than a substitute. It appears that those concerned with promoting virtual dissection in high school biology classrooms will have to develop simulations that are more compelling to the teachers. Additionally, if science teacher organizations want to reduce the controversy surrounding dissection, they may need to re-visit their positions on the importance of real animal dissection.

  18. Effects of Experimenting with Physical and Virtual Manipulatives on Students' Conceptual Understanding in Heat and Temperature

    ERIC Educational Resources Information Center

    Zacharia, Zacharias C.; Olympiou, Georgios; Papaevripidou, Marios

    2008-01-01

    This study aimed to investigate the comparative value of experimenting with physical manipulatives (PM) in a sequential combination with virtual manipulatives (VM), with the use of PM preceding the use of VM, and of experimenting with PM alone, with respect to changes in students' conceptual understanding in the domain of heat and temperature. A…

  19. Importance of the pharmacological profile of the bound ligand in enrichment on nuclear receptors: toward the use of experimentally validated decoy ligands.

    PubMed

    Lagarde, Nathalie; Zagury, Jean-François; Montes, Matthieu

    2014-10-27

    The evaluation of virtual ligand screening methods is of major importance to ensure their reliability. Taking into account the agonist/antagonist pharmacological profile should improve the quality of the benchmarking data sets since ligand binding can induce conformational changes in the nuclear receptor structure and such changes may vary according to the agonist/antagonist ligand profile. We indeed found that splitting the agonist and antagonist ligands into two separate data sets for a given nuclear receptor target significantly enhances the quality of the evaluation. The pharmacological profile of the ligand bound in the binding site of the target structure was also found to be an additional critical parameter. We also illustrate that active compound data sets for a given pharmacological activity can be used as a set of experimentally validated decoy ligands for another pharmacological activity to ensure a reliable and challenging evaluation of virtual screening methods.

  20. Low Friction Droplet Transportation on a Substrate with a Selective Leidenfrost Effect.

    PubMed

    Dodd, Linzi E; Wood, David; Geraldi, Nicasio R; Wells, Gary G; McHale, Glen; Xu, Ben B; Stuart-Cole, Simone; Martin, James; Newton, Michael I

    2016-08-31

    An energy saving Leidenfrost levitation method is introduced to transport microdroplets with virtually frictionless contact between the liquid and solid substrate. Through microengineering of the heating units, selective areas of the whole substrate can be electrothermally activated. A droplet can be levitated as a result of the Leidenfrost effect and further transported when the substrate is tilted slightly. Selective electroheating produces a uniform temperature distribution on the heating units within 1 s in response to a triggering voltage. Alongside these experimental observations, finite element simulations were conducted to understand the role of substrate thermal conductivity on the temperature profile of the selectively heated substrate. We also generated phase diagrams to verify the Leidenfrost regime for different substrate materials. Finally, we demonstrated the possibility of controlling low friction high speed droplet transportation (∼65 mm/s) when the substrate is tilted (∼7°) by structurally designing the substrate. This work establishes the basis for an entirely new approach to droplet microfluidics.

  1. VIRTUAL EMBRYO: SYSTEMS MODELING IN DEVELOPMENTAL TOXICITY - Symposium: SOT 2012

    EPA Science Inventory

    High-throughput screening (HTS) studies are providing a rich source of data that can be applied to in vitro profiling of chemical compounds for biological activity and potential toxicity. Chemical profiling in ToxCast covered 965 drugs-chemicals in over 500 diverse assays testing...

  2. Chimeric Plastics : a new class of thermoplastic

    NASA Astrophysics Data System (ADS)

    Sonnenschein, Mark

    A new class of thermoplastics (dubbed ``Chimerics'') is described that exhibits a high temperature glass transition followed by high performance elastomer properties, prior to melting. These transparent materials are comprised of co-continuous phase-separated block copolymers. One block is an amorphous glass with a high glass transition temperature, and the second is a higher temperature phase transition block creating virtual thermoreversible crosslinks. The material properties are highly influenced by phase separation on the order of 10-30 nanometers. At lower temperatures the polymer reflects the sum of the block copolymer properties. As the amorphous phase glass transition is exceeded, the virtual crosslinks of the higher temperature second phase dominate the plastic properties, resulting in rubber-like elasticity.

  3. Meteorological Simulations of Ozone Episode Case Days during the 1996 Paso del Norte Ozone Study

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

    Brown, M.J.; Costigan, K.; Muller, C.

    1999-02-01

    Meteorological simulations centered around the border cities of El Paso and Ciudad Juarez have been performed during an ozone episode that occurred on Aug. 13,1996 during the 1996 Paso del Norte Ozone Study field campaign. Simulations were petiormed using the HOTMAC mesoscale meteorological model using a 1,2,4, and 8 km horizontal grid size nested mesh system. Investigation of the vertical structure and evolution of the atmospheric boundary layer for the Aug. 11-13 time period is emphasized in this paper. Comparison of model-produced wind speed profiles to rawirisonde and radar profiler measurements shows reasonable agreement. A persistent upper-level jet was capturedmore » in the model simulations through data assimilation. In the evening hours, the model was not able to produce the strong wind direction shear seen in the radar wind profiles. Based on virtual potential temperature profile comparisons, the model appears to correctly simulate the daytime growth of the convective mixed layer. However, the model underestimates the cooling of the surface layer at night. We found that the upper-level jet significantly impacted the turbulence structure of the boundary layer, leading to relatively high turbulent kinetic energy (tke) values aloft at night. The model indicates that these high tke values aloft enhance the mid-morning growth of the boundary layer. No upper-level turbulence measurements were available to verify this finding, however. Radar profiler-derived mixing heights do indicate relatively rapid morning growth of the mixed layer.« less

  4. A theory for the retrieval of virtual temperature from winds, radiances and the equations of fluid dynamics

    NASA Technical Reports Server (NTRS)

    Tzvi, G. C.

    1986-01-01

    A technique to deduce the virtual temperature from the combined use of the equations of fluid dynamics, observed wind and observed radiances is described. The wind information could come from ground-based sensitivity very high frequency (VHF) Doppler radars and/or from space-borne Doppler lidars. The radiometers are also assumed to be either space-borne and/or ground-based. From traditional radiometric techniques the vertical structure of the temperature can be estimated only crudely. While it has been known for quite some time that the virtual temperature could be deduced from wind information only, such techniques had to assume the infallibility of certain diagnostic relations. The proposed technique is an extension of the Gal-Chen technique. It is assumed that due to modeling uncertainties the equations of fluid dynamics are satisfied only in the least square sense. The retrieved temperature, however, is constrained to reproduce the observed radiances. It is shown that the combined use of the three sources of information (wind, radiances and fluid dynamical equations) can result in a unique determination of the vertical temperature structure with spatial and temporal resolution comparable to that of the observed wind.

  5. Improved virtual cardiac phantom with variable diastolic filling rates and coronary artery velocities

    NASA Astrophysics Data System (ADS)

    Sturgeon, Gregory M.; Richards, Taylor W.; Samei, E.; Segars, W. P.

    2017-03-01

    To facilitate studies of measurement uncertainty in computed tomography angiography (CTA), we investigated the cardiac motion profile and resulting coronary artery motion utilizing innovative dynamic virtual and physical phantoms. The four-chamber cardiac finite element (FE) model developed in the Living Heart Project (LHP) served as the computational basis for our virtual cardiac phantom. This model provides deformation or strain information at high temporal and spatial resolution, exceeding that of speckle tracking echocardiography or tagged MRI. This model was extended by fitting its motion profile to left ventricular (LV) volume-time curves obtained from patient echocardiography data. By combining the dynamic patient variability from echo with the local strain information from the FE model, a series of virtual 4D cardiac phantoms were developed. Using the computational phantoms, we characterized the coronary motion and its effect on plaque imaging under a range of heart rates subject to variable diastolic function. The coronary artery motion was sampled at 248 spatial locations over 500 consecutive time frames. The coronary artery velocities were calculated as their average velocity during an acquisition window centered at each time frame, which minimized the discretization error. For the initial set of twelve patients, the diastatic coronary artery velocity ranged from 36.5 mm/s to 2.0 mm/s with a mean of 21.4 mm/s assuming an acquisition time of 75 ms. The developed phantoms have great potential in modeling cardiac imaging, providing a known truth and multiple realistic cardiac motion profiles to evaluate different image acquisition or reconstruction methods.

  6. Using a Virtual Classroom Environment to Describe the Attention Deficits Profile of Children with Neurofibromatosis Type 1

    ERIC Educational Resources Information Center

    Gilboa, Yafit; Rosenblum, Sara; Fattal-Valevski, Aviva; Toledano-Alhadef, Hagit; Rizzo, Albert; Josman, Naomi

    2011-01-01

    The objectives of this study were to describe the nature of the attention deficits in children with Neurofibromatosis type 1 (NF1) in comparison with typically developing (TD) children, using the Virtual Classroom (VC), and to assess the utility of this instrument for detecting attention deficits. Twenty-nine NF1 children and 25 age-and…

  7. Virtual Balancing for Studying and Training Postural Control.

    PubMed

    Buettner, Daniela; Dalin, Daniela; Wiesmeier, Isabella K; Maurer, Christoph

    2017-01-01

    Postural control during free stance has been frequently interpreted in terms of balancing an inverted pendulum. This even holds, if subjects do not balance their own, but an external body weight. We introduce here a virtual balancing apparatus, which produces torque in the ankle joint as a function of ankle angle resembling the gravity and inertial effects of free standing. As a first aim of this study, we systematically modified gravity, damping, and inertia to examine its effect on postural control beyond the physical constraints given in the real world. As a second aim, we compared virtual balancing to free stance to test its suitability for balance training in patients who are not able to balance their full body weight due to certain medical conditions. In a feasibility study, we analyzed postural control during free stance and virtual balancing in 15 healthy subjects. Postural control was characterized by spontaneous sway measures and measures of perturbed stance. During free stance, perturbations were induced by pseudorandom anterior-posterior tilts of the body support surface. In the virtual balancing task, we systematically varied the anterior-posterior position of the foot plate where the balancing forces are zero following a similar pseudorandom stimulus profile. We found that subjects' behavior during virtual balancing resembles free stance on a tilting platform. This specifically holds for the profile of body excursions as a function of stimulus frequencies. Moreover, non-linearity between stimulus and response amplitude is similar in free and virtual balancing. The overall larger stimulus induced body excursions together with an altered phase behavior between stimulus and response could be in part explained by the limited use of vestibular and visual feedback in our experimental setting. Varying gravity or damping significantly affected postural behavior. Inertia as an isolated factor had a mild effect on the response functions. We conclude that virtual balancing may be well suited to simulate conditions which could otherwise only be realized in space experiments or during parabolic flights. Further studies are needed to examine patients' potential benefit of virtual balance training.

  8. Virtual Balancing for Studying and Training Postural Control

    PubMed Central

    Buettner, Daniela; Dalin, Daniela; Wiesmeier, Isabella K.; Maurer, Christoph

    2017-01-01

    Postural control during free stance has been frequently interpreted in terms of balancing an inverted pendulum. This even holds, if subjects do not balance their own, but an external body weight. We introduce here a virtual balancing apparatus, which produces torque in the ankle joint as a function of ankle angle resembling the gravity and inertial effects of free standing. As a first aim of this study, we systematically modified gravity, damping, and inertia to examine its effect on postural control beyond the physical constraints given in the real world. As a second aim, we compared virtual balancing to free stance to test its suitability for balance training in patients who are not able to balance their full body weight due to certain medical conditions. In a feasibility study, we analyzed postural control during free stance and virtual balancing in 15 healthy subjects. Postural control was characterized by spontaneous sway measures and measures of perturbed stance. During free stance, perturbations were induced by pseudorandom anterior-posterior tilts of the body support surface. In the virtual balancing task, we systematically varied the anterior-posterior position of the foot plate where the balancing forces are zero following a similar pseudorandom stimulus profile. We found that subjects' behavior during virtual balancing resembles free stance on a tilting platform. This specifically holds for the profile of body excursions as a function of stimulus frequencies. Moreover, non-linearity between stimulus and response amplitude is similar in free and virtual balancing. The overall larger stimulus induced body excursions together with an altered phase behavior between stimulus and response could be in part explained by the limited use of vestibular and visual feedback in our experimental setting. Varying gravity or damping significantly affected postural behavior. Inertia as an isolated factor had a mild effect on the response functions. We conclude that virtual balancing may be well suited to simulate conditions which could otherwise only be realized in space experiments or during parabolic flights. Further studies are needed to examine patients' potential benefit of virtual balance training. PMID:29018320

  9. Ferromagnetic ordering in Mn-doped quantum wells GaAs-AlGaAs resulting from the virtual Anderson transition

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

    Agrinskaya, N. V.; Berezovets, V. A.; Bouravlev, A.

    We present our results obtained for Mn-doped GaAs quantum wells where the evidences of the ferromagnetic transition at relatively high temperatures were found at unusually small Mn concentrations. The observed values of hopping resistance at small temperatures evidenced that the samples are deep in the insulating regime. Thus the corresponding estimates of the overlapping integrals can hardly explain the large values of Curie temperatures T{sub c} ≃ 100 K. We develop a theoretical model qualitatively explaining the experimental results basing on the concept of virtual Anderson transition.

  10. Thermal stresses in composite tubes using complementary virtual work

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Cooper, D. E.

    1988-01-01

    This paper addresses the computation of thermally induced stresses in layered, fiber-reinforced composite tubes subjected to a circumferential gradient. The paper focuses on using the principle of complementary virtual work, in conjunction with a Ritz approximation to the stress field, to study the influence on the predicted stresses of including temperature-dependent material properties. Results indicate that the computed values of stress are sensitive to the temperature dependence of the matrix-direction compliance and matrix-direction thermal expansion in the plane of the lamina. There is less sensitivity to the temperature dependence of the other material properties.

  11. Analyzing Members' Motivations to Participate in Role-Playing and Self-Expression Based Virtual Communities

    NASA Astrophysics Data System (ADS)

    Lee, Young Eun; Saharia, Aditya

    With the rapid growth of computer mediated communication technologies in the last two decades, various types of virtual communities have emerged. Some communities provide a role playing arena, enabled by avatars, while others provide an arena for expressing and promoting detailed personal profiles to enhance their offline social networks. Due to different focus of these virtual communities, different factors motivate members to participate in these communities. In this study, we examine differences in members’ motivations to participate in role-playing versus self-expression based virtual communities. To achieve this goal, we apply the Wang and Fesenmaier (2004) framework, which explains members’ participation in terms of their functional, social, psychological, and hedonic needs. The primary contributions of this study are two folds: First, it demonstrates differences between role-playing and self-expression based communities. Second, it provides a comprehensive framework describing members’ motivation to participate in virtual communities.

  12. Identification of novel antitubulin agents by using a virtual screening approach based on a 7-point pharmacophore model of the tubulin colchi-site.

    PubMed

    Massarotti, Alberto; Theeramunkong, Sewan; Mesenzani, Ornella; Caldarelli, Antonio; Genazzani, Armando A; Tron, Gian Cesare

    2011-12-01

    Tubulin inhibition represents an established target in the field of anticancer research, and over the last 20 years, an intensive search for new antimicrotubule agents has occurred. Indeed, in silico models have been presented that might aid the discovery of novel agents. Among these, a 7-point pharmacophore model has been recently proposed. As a formal proof of this model, we carried out a ligand-based virtual screening on the colchicine-binding site. In vitro testing demonstrated that two compounds displayed a cytotoxic profile on neuroblastoma cancer cells (SH-SY5H) and one had an antitubulinic profile. © 2011 John Wiley & Sons A/S.

  13. SU-F-T-436: A Method to Evaluate Dosimetric Properties of SFGRT in Eclipse TPS

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

    Xu, M; Tobias, R; Pankuch, M

    Purpose: The objective was to develop a method for dose distribution calculation of spatially-fractionated-GRID-radiotherapy (SFGRT) in Eclipse treatment-planning-system (TPS). Methods: Patient treatment-plans with SFGRT for bulky tumors were generated in Varian Eclipse version11. A virtual structure based on the GRID pattern was created and registered to a patient CT image dataset. The virtual GRID structure was positioned on the iso-center level together with matching beam geometries to simulate a commercially available GRID block made of brass. This method overcame the difficulty in treatment-planning and dose-calculation due to the lack o-the option to insert a GRID block add-on in Eclipse TPS.more » The patient treatment-planning displayed GRID effects on the target, critical structures, and dose distribution. The dose calculations were compared to the measurement results in phantom. Results: The GRID block structure was created to follow the beam divergence to the patient CT images. The inserted virtual GRID block made it possible to calculate the dose distributions and profiles at various depths in Eclipse. The virtual GRID block was added as an option to TPS. The 3D representation of the isodose distribution of the spatially-fractionated beam was generated in axial, coronal, and sagittal planes. Physics of GRID can be different from that for fields shaped by regular blocks because the charge-particle-equilibrium cannot be guaranteed for small field openings. Output factor (OF) measurement was required to calculate the MU to deliver the prescribed dose. The calculated OF based on the virtual GRID agreed well with the measured OF in phantom. Conclusion: The method to create the virtual GRID block has been proposed for the first time in Eclipse TPS. The dosedistributions, in-plane and cross-plane profiles in PTV can be displayed in 3D-space. The calculated OF’s based on the virtual GRID model compare well to the measured OF’s for SFGRT clinical use.« less

  14. Virtual Reality Transfer Protocol (VRTP): Implementing a Monitor Application for the Real-Time Transport Protocol (RTP) Using the JAVA Media Framework (JMF)

    DTIC Science & Technology

    1999-09-01

    application, a complete specification will require one or more companion documents, as follows. 1. Profile Specification Documents A Profile...Rio de Janeiro - RJ - Brazil 21. Diretoria de Sistemas de Armas da Marinha Rua Primeiro de Marco, 118 Rio de Janeiro - RJ - Brazil CEP 20010 22

  15. Recognition profile of emotions in natural and virtual faces.

    PubMed

    Dyck, Miriam; Winbeck, Maren; Leiberg, Susanne; Chen, Yuhan; Gur, Ruben C; Gur, Rurben C; Mathiak, Klaus

    2008-01-01

    Computer-generated virtual faces become increasingly realistic including the simulation of emotional expressions. These faces can be used as well-controlled, realistic and dynamic stimuli in emotion research. However, the validity of virtual facial expressions in comparison to natural emotion displays still needs to be shown for the different emotions and different age groups. Thirty-two healthy volunteers between the age of 20 and 60 rated pictures of natural human faces and faces of virtual characters (avatars) with respect to the expressed emotions: happiness, sadness, anger, fear, disgust, and neutral. Results indicate that virtual emotions were recognized comparable to natural ones. Recognition differences in virtual and natural faces depended on specific emotions: whereas disgust was difficult to convey with the current avatar technology, virtual sadness and fear achieved better recognition results than natural faces. Furthermore, emotion recognition rates decreased for virtual but not natural faces in participants over the age of 40. This specific age effect suggests that media exposure has an influence on emotion recognition. Virtual and natural facial displays of emotion may be equally effective. Improved technology (e.g. better modelling of the naso-labial area) may lead to even better results as compared to trained actors. Due to the ease with which virtual human faces can be animated and manipulated, validated artificial emotional expressions will be of major relevance in future research and therapeutic applications.

  16. Recognition Profile of Emotions in Natural and Virtual Faces

    PubMed Central

    Dyck, Miriam; Winbeck, Maren; Leiberg, Susanne; Chen, Yuhan; Gur, Rurben C.; Mathiak, Klaus

    2008-01-01

    Background Computer-generated virtual faces become increasingly realistic including the simulation of emotional expressions. These faces can be used as well-controlled, realistic and dynamic stimuli in emotion research. However, the validity of virtual facial expressions in comparison to natural emotion displays still needs to be shown for the different emotions and different age groups. Methodology/Principal Findings Thirty-two healthy volunteers between the age of 20 and 60 rated pictures of natural human faces and faces of virtual characters (avatars) with respect to the expressed emotions: happiness, sadness, anger, fear, disgust, and neutral. Results indicate that virtual emotions were recognized comparable to natural ones. Recognition differences in virtual and natural faces depended on specific emotions: whereas disgust was difficult to convey with the current avatar technology, virtual sadness and fear achieved better recognition results than natural faces. Furthermore, emotion recognition rates decreased for virtual but not natural faces in participants over the age of 40. This specific age effect suggests that media exposure has an influence on emotion recognition. Conclusions/Significance Virtual and natural facial displays of emotion may be equally effective. Improved technology (e.g. better modelling of the naso-labial area) may lead to even better results as compared to trained actors. Due to the ease with which virtual human faces can be animated and manipulated, validated artificial emotional expressions will be of major relevance in future research and therapeutic applications. PMID:18985152

  17. The Design of a Chemical Virtual Instrument Based on LabVIEW for Determining Temperatures and Pressures.

    PubMed

    Wang, Wen-Bin; Li, Jang-Yuan; Wu, Qi-Jun

    2007-01-01

    A LabVIEW-based self-constructed chemical virtual instrument (VI) has been developed for determining temperatures and pressures. It can be put together easily and quickly by selecting hardware modules, such as the PCI-DAQ card or serial port method, different kinds of sensors, signal-conditioning circuits or finished chemical instruments, and software modules such as data acquisition, saving, proceeding. The VI system provides individual and extremely flexible solutions for automatic measurements in physical chemistry research.

  18. The Design of a Chemical Virtual Instrument Based on LabVIEW for Determining Temperatures and Pressures

    PubMed Central

    Wang, Wen-Bin; Li, Jang-Yuan; Wu, Qi-Jun

    2007-01-01

    A LabVIEW-based self-constructed chemical virtual instrument (VI) has been developed for determining temperatures and pressures. It can be put together easily and quickly by selecting hardware modules, such as the PCI-DAQ card or serial port method, different kinds of sensors, signal-conditioning circuits or finished chemical instruments, and software modules such as data acquisition, saving, proceeding. The VI system provides individual and extremely flexible solutions for automatic measurements in physical chemistry research. PMID:17671611

  19. Introduction on performance analysis and profiling methodologies for KVM on ARM virtualization

    NASA Astrophysics Data System (ADS)

    Motakis, Antonios; Spyridakis, Alexander; Raho, Daniel

    2013-05-01

    The introduction of hardware virtualization extensions on ARM Cortex-A15 processors has enabled the implementation of full virtualization solutions for this architecture, such as KVM on ARM. This trend motivates the need to quantify and understand the performance impact, emerged by the application of this technology. In this work we start looking into some interesting performance metrics on KVM for ARM processors, which can provide us with useful insight that may lead to potential improvements in the future. This includes measurements such as interrupt latency and guest exit cost, performed on ARM Versatile Express and Samsung Exynos 5250 hardware platforms. Furthermore, we discuss additional methodologies that can provide us with a deeper understanding in the future of the performance footprint of KVM. We identify some of the most interesting approaches in this field, and perform a tentative analysis on how these may be implemented in the KVM on ARM port. These take into consideration hardware and software based counters for profiling, and issues related to the limitations of the simulators which are often used, such as the ARM Fast Models platform.

  20. An interactive tool for outdoor computer controlled cultivation of microalgae in a tubular photobioreactor system.

    PubMed

    Dormido, Raquel; Sánchez, José; Duro, Natividad; Dormido-Canto, Sebastián; Guinaldo, María; Dormido, Sebastián

    2014-03-06

    This paper describes an interactive virtual laboratory for experimenting with an outdoor tubular photobioreactor (henceforth PBR for short). This virtual laboratory it makes possible to: (a) accurately reproduce the structure of a real plant (the PBR designed and built by the Department of Chemical Engineering of the University of Almería, Spain); (b) simulate a generic tubular PBR by changing the PBR geometry; (c) simulate the effects of changing different operating parameters such as the conditions of the culture (pH, biomass concentration, dissolved O2, inyected CO2, etc.); (d) simulate the PBR in its environmental context; it is possible to change the geographic location of the system or the solar irradiation profile; (e) apply different control strategies to adjust different variables such as the CO2 injection, culture circulation rate or culture temperature in order to maximize the biomass production; (f) simulate the harvesting. In this way, users can learn in an intuitive way how productivity is affected by any change in the design. It facilitates the learning of how to manipulate essential variables for microalgae growth to design an optimal PBR. The simulator has been developed with Easy Java Simulations, a freeware open-source tool developed in Java, specifically designed for the creation of interactive dynamic simulations.

  1. An Interactive Tool for Outdoor Computer Controlled Cultivation of Microalgae in a Tubular Photobioreactor System

    PubMed Central

    Dormido, Raquel; Sánchez, José; Duro, Natividad; Dormido-Canto, Sebastián; Guinaldo, María; Dormido, Sebastián

    2014-01-01

    This paper describes an interactive virtual laboratory for experimenting with an outdoor tubular photobioreactor (henceforth PBR for short). This virtual laboratory it makes possible to: (a) accurately reproduce the structure of a real plant (the PBR designed and built by the Department of Chemical Engineering of the University of Almería, Spain); (b) simulate a generic tubular PBR by changing the PBR geometry; (c) simulate the effects of changing different operating parameters such as the conditions of the culture (pH, biomass concentration, dissolved O2, inyected CO2, etc.); (d) simulate the PBR in its environmental context; it is possible to change the geographic location of the system or the solar irradiation profile; (e) apply different control strategies to adjust different variables such as the CO2 injection, culture circulation rate or culture temperature in order to maximize the biomass production; (f) simulate the harvesting. In this way, users can learn in an intuitive way how productivity is affected by any change in the design. It facilitates the learning of how to manipulate essential variables for microalgae growth to design an optimal PBR. The simulator has been developed with Easy Java Simulations, a freeware open-source tool developed in Java, specifically designed for the creation of interactive dynamic simulations. PMID:24662450

  2. Comparing the influence of physical and virtual manipulatives in the context of the Physics by Inquiry curriculum: The case of undergraduate students' conceptual understanding of heat and temperature

    NASA Astrophysics Data System (ADS)

    Zacharia, Zacharias C.; Constantinou, Constantinos P.

    2008-04-01

    We compare the effect of experimenting with physical or virtual manipulatives on undergraduate students' conceptual understanding of heat and temperature. A pre-post comparison study design was used to replicate all aspects of a guided inquiry classroom except the mode in which students performed their experiments. This study is the first on physical and virtual manipulative experimentation in physics in which the curriculum, method of instruction, and resource capabilities were explicitly controlled. The participants were 68 undergraduates in an introductory course and were randomly assigned to an experimental or a control group. Conceptual tests were administered to both groups to assess students' understanding before, during, and after instruction. The result indicates that both modes of experimentation are equally effective in enhancing students' conceptual understanding. This result is discussed in the context of an ongoing debate on the relative importance of virtual and real laboratory work in physics education.

  3. Three-dimensional virtual operations can facilitate complicated surgical planning for the treatment of patients with jaw deformities associated with facial asymmetry: a case report.

    PubMed

    Hara, Shingo; Mitsugi, Masaharu; Kanno, Takahiro; Nomachi, Akihiko; Wajima, Takehiko; Tatemoto, Yukihiro

    2013-09-01

    This article describes a case we experienced in which good postsurgical facial profiles were obtained for a patient with jaw deformities associated with facial asymmetry, by implementing surgical planning with SimPlant OMS. Using this method, we conducted LF1 osteotomy, intraoral vertical ramus osteotomy (IVRO), sagittal split ramus osteotomy (SSRO), mandibular constriction and mandibular border genioplasty. Not only did we obtain a class I occlusal relationship, but the complicated surgery also improved the asymmetry of the frontal view, as well as of the profile view, of the patient. The virtual operation using three-dimensional computed tomography (3D-CT) could be especially useful for the treatment of patients with jaw deformities associated with facial asymmetry.

  4. Three-dimensional virtual operations can facilitate complicated surgical planning for the treatment of patients with jaw deformities associated with facial asymmetry: a case report

    PubMed Central

    Hara, Shingo; Mitsugi, Masaharu; Kanno, Takahiro; Nomachi, Akihiko; Wajima, Takehiko; Tatemoto, Yukihiro

    2013-01-01

    This article describes a case we experienced in which good postsurgical facial profiles were obtained for a patient with jaw deformities associated with facial asymmetry, by implementing surgical planning with SimPlant OMS. Using this method, we conducted LF1 osteotomy, intraoral vertical ramus osteotomy (IVRO), sagittal split ramus osteotomy (SSRO), mandibular constriction and mandibular border genioplasty. Not only did we obtain a class I occlusal relationship, but the complicated surgery also improved the asymmetry of the frontal view, as well as of the profile view, of the patient. The virtual operation using three-dimensional computed tomography (3D-CT) could be especially useful for the treatment of patients with jaw deformities associated with facial asymmetry. PMID:23907678

  5. Thin SiGe virtual substrates for Ge heterostructures integration on silicon

    NASA Astrophysics Data System (ADS)

    Cecchi, S.; Gatti, E.; Chrastina, D.; Frigerio, J.; Müller Gubler, E.; Paul, D. J.; Guzzi, M.; Isella, G.

    2014-03-01

    The possibility to reduce the thickness of the SiGe virtual substrate, required for the integration of Ge heterostructures on Si, without heavily affecting the crystal quality is becoming fundamental in several applications. In this work, we present 1 μm thick Si1-xGex buffers (with x > 0.7) having different designs which could be suitable for applications requiring a thin virtual substrate. The rationale is to reduce the lattice mismatch at the interface with the Si substrate by introducing composition steps and/or partial grading. The relatively low growth temperature (475 °C) makes this approach appealing for complementary metal-oxide-semiconductor integration. For all the investigated designs, a reduction of the threading dislocation density compared to constant composition Si1-xGex layers was observed. The best buffer in terms of defects reduction was used as a virtual substrate for the deposition of a Ge/SiGe multiple quantum well structure. Room temperature optical absorption and photoluminescence analysis performed on nominally identical quantum wells grown on both a thick graded virtual substrate and the selected thin buffer demonstrates a comparable optical quality, confirming the effectiveness of the proposed approach.

  6. Upper limb assessment using a Virtual Peg Insertion Test.

    PubMed

    Fluet, Marie-Christine; Lambercy, Olivier; Gassert, Roger

    2011-01-01

    This paper presents the initial evaluation of a Virtual Peg Insertion Test developed to assess sensorimotor functions of arm and hand using an instrumented tool, virtual reality and haptic feedback. Nine performance parameters derived from kinematic and kinetic data were selected and compared between two groups of healthy subjects performing the task with the dominant and non-dominant hand, as well as with a group of chronic stroke subjects suffering from different levels of upper limb impairment. Results showed significantly smaller grasping forces applied by the stroke subjects compared to the healthy subjects. The grasping force profiles suggest a poor coordination between position and grasping for the stroke subjects, and the collision forces with the virtual board were found to be indicative of sensory deficits. These preliminary results suggest that the analyzed parameters could be valid indicators of impairment. © 2011 IEEE

  7. Single-camera stereo-digital image correlation with a four-mirror adapter: optimized design and validation

    NASA Astrophysics Data System (ADS)

    Yu, Liping; Pan, Bing

    2016-12-01

    A low-cost, easy-to-implement but practical single-camera stereo-digital image correlation (DIC) system using a four-mirror adapter is established for accurate shape and three-dimensional (3D) deformation measurements. The mirrors assisted pseudo-stereo imaging system can convert a single camera into two virtual cameras, which view a specimen from different angles and record the surface images of the test object onto two halves of the camera sensor. To enable deformation measurement in non-laboratory conditions or extreme high temperature environments, an active imaging optical design, combining an actively illuminated monochromatic source with a coupled band-pass optical filter, is compactly integrated to the pseudo-stereo DIC system. The optical design, basic principles and implementation procedures of the established system for 3D profile and deformation measurements are described in detail. The effectiveness and accuracy of the established system are verified by measuring the profile of a regular cylinder surface and displacements of a translated planar plate. As an application example, the established system is used to determine the tensile strains and Poisson's ratio of a composite solid propellant specimen during stress relaxation test. Since the established single-camera stereo-DIC system only needs a single camera and presents strong robustness against variations in ambient light or the thermal radiation of a hot object, it demonstrates great potential in determining transient deformation in non-laboratory or high-temperature environments with the aid of a single high-speed camera.

  8. Multiplexing Low and High QoS Workloads in Virtual Environments

    NASA Astrophysics Data System (ADS)

    Verboven, Sam; Vanmechelen, Kurt; Broeckhove, Jan

    Virtualization technology has introduced new ways for managing IT infrastructure. The flexible deployment of applications through self-contained virtual machine images has removed the barriers for multiplexing, suspending and migrating applications with their entire execution environment, allowing for a more efficient use of the infrastructure. These developments have given rise to an important challenge regarding the optimal scheduling of virtual machine workloads. In this paper, we specifically address the VM scheduling problem in which workloads that require guaranteed levels of CPU performance are mixed with workloads that do not require such guarantees. We introduce a framework to analyze this scheduling problem and evaluate to what extent such mixed service delivery is beneficial for a provider of virtualized IT infrastructure. Traditionally providers offer IT resources under a guaranteed and fixed performance profile, which can lead to underutilization. The findings of our simulation study show that through proper tuning of a limited set of parameters, the proposed scheduling algorithm allows for a significant increase in utilization without sacrificing on performance dependability.

  9. A study of planetary meteorology

    NASA Technical Reports Server (NTRS)

    Ohring, G.

    1973-01-01

    Inversion techniques are applied to the few earth based observations of the Jovian emission spectrum to obtain directly the profiles of atmospheric temperature and ammonia abundance. The temperature profile is characterized by a definite tropopause region with a temperature of about 115K and a stratospheric region in which the temperature slowly increases with altitude. The derived ammonia profile indicates the presence of a saturated ammonia layer with a base temperature of approximately 14OK. The concept is described deducing the temperature and constituent profile of a planetary atmosphere from orbiter measurements of the planet's IR limb radiance profile. Analysis of the weighting functions for the Martian atmosphere indicates that a limb radiance profile in the 15 micron CO2 band can be used to determine the Martian atmospheric temperature profile from 20 to 60 km.

  10. Determining the tensile response of materials at high temperature using DIC and the Virtual Fields Method

    NASA Astrophysics Data System (ADS)

    Valeri, Guillermo; Koohbor, Behrad; Kidane, Addis; Sutton, Michael A.

    2017-04-01

    An experimental approach based on Digital Image Correlation (DIC) is successfully applied to predict the uniaxial stress-strain response of 304 stainless steel specimens subjected to nominally uniform temperatures ranging from room temperature to 900 °C. A portable induction heating device equipped with custom made water-cooled copper coils is used to heat the specimen. The induction heater is used in conjunction with a conventional tensile frame to enable high temperature tension experiments. A stereovision camera system equipped with appropriate band pass filters is employed to facilitate the study of full-field deformation response of the material at elevated temperatures. Using the temperature and load histories along with the full-field strain data, a Virtual Fields Method (VFM) based approach is implemented to identify constitutive parameters governing the plastic deformation of the material at high temperature conditions. Results from these experiments confirm that the proposed method can be used to measure the full field deformation of materials subjected to thermo-mechanical loading.

  11. Keeping it cool: unraveling the influences on stream temperature.

    Treesearch

    Jonathan Thompson

    2005-01-01

    Water temperature influences virtually every biotic component of stream ecosystems. Not surprisingly, increased summer temperatures in streams with coldwater species of fish such as salmon and trout have become a topic of concern regionally and internationally. Although stream temperature has been studied for many years, controversy continues over the relative...

  12. Stability of Zircon and its Isotopic Ratios in High-Temperature Fluids: Long-Term (4 months) Isotope Exchange Experiment at 850 °C and 50 MPa

    NASA Astrophysics Data System (ADS)

    Bindeman, Ilya N.; Schmitt, Axel K.; Lundstrom, Craig C.; Hervig, Richard L.

    2018-05-01

    Stability of zircon in hydrothermal fluids and vanishingly slow rates of diffusion identify zircon as a reliable recorder of its formation conditions in recent and ancient rocks. Debate, however, persists on how rapidly oxygen and key trace elements (e.g., Li, B, Pb) diffuse when zircon is exposed to hot aqueous fluids. Here, we report results of a nano- to micrometer-scale investigation of isotopic exchange using natural zircon from Mesa Falls Tuff (Yellowstone) treated with quartz-saturated, isotopically (18O, D, 7Li, and 11B) labeled water with a nominal δ18O value of +450‰ over 4 months at 850°C and 50 MPa. Frontside (crystal rim inwards) δ18O depth profiling of zircon by magnetic sector SIMS shows initially high but decreasing 18O/16O over a 130 nm non-Fickian profile, with a decay length comparable to the signal from surficial Au coating deposited onto zircon. In contrast, backside (crystal interior outwards) depth profiling on a 2-3 µm thick wafer cut and thinned from treated zircon by focused ion beam (FIB) milling lacks any significant increase in 18O/16O during penetration of the original surface layer. Near-surface time-of-flight (TOF-SIMS) frontside profiles of uncoated zircon from 4-month and 1-day-long experiments as well as untreated zircons display similar enrichments of 18O over a distance of 20 nm. All frontside 18O profiles are here interpreted as transient surface signals from nm-thick surface enrichment or contamination unrelated to diffusion. Likewise, frontside depth profiling of H, Li, and B isotopes are similar for long- and short-duration experiments. Additionally, surface U-Pb dating of zircon from the 4-month experiment returned U-Pb ages by depth profiling with 1 µm penetration that were identical to untreated samples. Frontside and backside depth-profiling thus demonstrate that diffusive 18O enrichment in the presence of H2O is much slower than predicted from experiments in Watson and Cherniak (1997). Instead, intracrystalline exchange of oxygen between fluid and zircon in wet experimental conditions with excess silica occurred over length-scales equivalent to those predicted for dry diffusion. Oxygen diffusion coefficients even under wet conditions and elevated temperatures (850 °C) are <1-3×10-23 m2/sec, underscoring a virtual lack of oxygen diffusion and an outstanding survivability of zircons

  13. Estimation of Transformation Temperatures in Ti-Ni-Pd Shape Memory Alloys

    NASA Astrophysics Data System (ADS)

    Narayana, P. L.; Kim, Seong-Woong; Hong, Jae-Keun; Reddy, N. S.; Yeom, Jong-Taek

    2018-03-01

    The present study focused on estimating the complex nonlinear relationship between the composition and phase transformation temperatures of Ti-Ni-Pd shape memory alloys by artificial neural networks (ANN). The ANN models were developed by using the experimental data of Ti-Ni-Pd alloys. It was found that the predictions are in good agreement with the trained and unseen test data of existing alloys. The developed model was able to simulate new virtual alloys to quantitatively estimate the effect of Ti, Ni, and Pd on transformation temperatures. The transformation temperature behavior of these virtual alloys is validated by conducting new experiments on the Ti-rich thin film that was deposited using multi target sputtering equipment. The transformation behavior of the film was measured by varying the composition with the help of aging treatment. The predicted trend of transformational temperatures was explained with the help of experimental results.

  14. Vertical structure of atmospheric boundary layer over Ranchi during the summer monsoon season

    NASA Astrophysics Data System (ADS)

    Chandra, Sagarika; Srivastava, Nishi; Kumar, Manoj

    2018-04-01

    Thermodynamic structure and variability in the atmospheric boundary layer have been investigated with the help of balloon-borne GPS radiosonde over a monsoon trough station Ranchi (Lat. 23°45'N, Long. 85°43'E, India) during the summer monsoon season (June-September) for a period of 2011-2013. Virtual potential temperature gradient method is used for the determination of mixed layer height (MLH). The MLH has been found to vary in the range of 1000-1300 m during the onset, 600-900 m during the active and 1400-1750 m during the break phase of monsoon over this region. Inter-annual variations noticed in MLH could be associated with inter-annual variability in convection and rainfall prevailing over the region. Along with the MLH, the cloud layer heights are also derived from the thermodynamic profiles for the onset, active and break phases of monsoon. Cloud layer height varied a lot during different phases of the monsoon. For the determination of boundary-layer convection, thermodynamic parameter difference (δθ = θ es- θ e) between saturated equivalent potential temperature (θ es ) and equivalent potential temperature (θ e) is used. It is a good indicator of convection and indicates the intense and suppressed convection during different phases of monsoon.

  15. Lateral carrier diffusion in InGaAs/GaAs coupled quantum dot-quantum well system

    NASA Astrophysics Data System (ADS)

    Pieczarka, M.; Syperek, M.; Biegańska, D.; Gilfert, C.; Pavelescu, E. M.; Reithmaier, J. P.; Misiewicz, J.; Sek, G.

    2017-05-01

    The lateral carrier diffusion process is investigated in coupled InGaAs/GaAs quantum dot-quantum well (QD-QW) structures by means of spatially resolved photoluminescence spectroscopy at low temperature. Under non-resonant photo-excitation above the GaAs bandgap, the lateral carrier transport reflected in the distorted electron-hole pair emission profiles is found to be mainly governed by high energy carriers created within the 3D density of states of GaAs. In contrast, for the case of resonant excitation tuned to the QW-like ground state of the QD-QW system, the emission profiles remain unaffected by the excess kinetic energy of carriers and local phonon heating within the pump spot. The lateral diffusion lengths are determined and present certain dependency on the coupling strength between QW and QDs. While for a strongly coupled structure the diffusion length is found to be around 0.8 μm and monotonically increases up to 1.4 μm with the excitation power density, in weakly coupled structures, it is determined to ca. 1.6 μm and remained virtually independent of the pumping power density.

  16. Ionosphere Profile Estimation Using Ionosonde & GPS Data in an Inverse Refraction Calculation

    NASA Astrophysics Data System (ADS)

    Psiaki, M. L.

    2014-12-01

    A method has been developed to assimilate ionosonde virtual heights and GPS slant TEC data to estimate the parameters of a local ionosphere model, including estimates of the topside and of latitude and longitude variations. This effort seeks to better assimilate a variety of remote sensing data in order to characterize local (and eventually regional and global) ionosphere electron density profiles. The core calculations involve a forward refractive ray-tracing solution and a nonlinear optimal estimation algorithm that inverts the forward model. The ray-tracing calculations solve a nonlinear two-point boundary value problem for the curved ionosonde or GPS ray path through a parameterized electron density profile. It implements a full 3D solution that can handle the case of a tilted ionosphere. These calculations use Hamiltonian equivalents of the Appleton-Hartree magneto-plasma refraction index model. The current ionosphere parameterization is a modified Booker profile. It has been augmented to include latitude and longitude dependencies. The forward ray-tracing solution yields a given signal's group delay and beat carrier phase observables. An auxiliary set of boundary value problem solutions determine the sensitivities of the ray paths and observables with respect to the parameters of the augmented Booker profile. The nonlinear estimation algorithm compares the measured ionosonde virtual-altitude observables and GPS slant-TEC observables to the corresponding values from the forward refraction model. It uses the parameter sensitivities of the model to iteratively improve its parameter estimates in a way the reduces the residual errors between the measurements and their modeled values. This method has been applied to data from HAARP in Gakona, AK and has produced good TEC and virtual height fits. It has been extended to characterize electron density perturbations caused by HAARP heating experiments through the use of GPS slant TEC data for an LOS through the heated zone. The next planned extension of the method is to estimate the parameters of a regional ionosphere profile. The input observables will be slant TEC from an array of GPS receivers and group delay and carrier phase observables from an array of high-frequency beacons. The beacon array will function as a sort of multi-static ionosonde.

  17. Rethinking the longitudinal stream temperature paradigm: region-wide comparison of thermal infrared imagery reveals unexpected complexity of river temperatures

    USGS Publications Warehouse

    Fullerton, Aimee H.; Torgersen, Christian E.; Lawler, Joshua J.; Faux, Russell N.; Steel, E. Ashley; Beechie, Timothy J.; Ebersole, Joseph L.; Leibowitz, Scott J.

    2015-01-01

    Prevailing theory suggests that stream temperature warms asymptotically in a downstream direction, beginning at the temperature of the source in the headwaters and leveling off downstream as it converges to match meteorological conditions. However, there have been few empirical examples of longitudinal patterns of temperature in large rivers due to a paucity of data. We constructed longitudinal thermal profiles (temperature versus distance) for 53 rivers in the Pacific Northwest (USA) using an extensive dataset of remotely sensed summertime river temperatures and classified each profile into one of five patterns of downstream warming: asymptotic (increasing then flattening), linear (increasing steadily), uniform (not changing), parabolic (increasing then decreasing), or complex (not fitting other classes). We evaluated (1) how frequently profiles warmed asymptotically downstream as expected, and (2) whether relationships between river temperature and common hydroclimatic variables differed by profile class. We found considerable diversity in profile shape, with 47% of rivers warming asymptotically, and 53% having alternative profile shapes. Water temperature did not warm substantially over the course of the river for coastal parabolic and uniform profiles, and for some linear and complex profiles. Profile classes showed no clear geographical trends. The degree of correlation between river temperature and hydroclimatic variables differed among profile classes, but there was overlap among classes. Water temperature in rivers with asymptotic or parabolic profiles was positively correlated with August air temperature, tributary temperature and velocity, and negatively correlated with elevation, August precipitation, gradient, and distance upstream. Conversely, associations were less apparent in rivers with linear, uniform, or complex profiles. Factors contributing to the unique shape of parabolic profiles differed for coastal and inland rivers, where downstream cooling was influenced locally by climate or cool water inputs, respectively. Potential drivers of shape for complex profiles were specific to each river. These thermal patterns indicate diverse thermal habitats that may promote resilience of aquatic biota to climate change. Without this spatial context, climate change models may incorrectly estimate loss of thermally suitable habitat.

  18. Artificial plasma cusp generated by upper hybrid instabilities in HF heating experiments at HAARP

    NASA Astrophysics Data System (ADS)

    Kuo, Spencer; Snyder, Arnold

    2013-05-01

    High Frequency Active Auroral Research Program digisonde was operated in a fast mode to record ionospheric modifications by the HF heating wave. With the O mode heater of 3.2 MHz turned on for 2 min, significant virtual height spread was observed in the heater off ionograms, acquired beginning the moment the heater turned off. Moreover, there is a noticeable bump in the virtual height spread of the ionogram trace that appears next to the plasma frequency (~ 2.88 MHz) of the upper hybrid resonance layer of the HF heating wave. The enhanced spread and the bump disappear in the subsequent heater off ionograms recorded 1 min later. The height distribution of the ionosphere in the spread situation indicates that both electron density and temperature increases exceed 10% over a large altitude region (> 30 km) from below to above the upper hybrid resonance layer. This "mini cusp" (bump) is similar to the cusp occurring in daytime ionograms at the F1-F2 layer transition, indicating that there is a small ledge in the density profile reminiscent of F1-F2 layer transitions. Two parametric processes exciting upper hybrid waves as the sidebands by the HF heating waves are studied. Field-aligned purely growing mode and lower hybrid wave are the respective decay modes. The excited upper hybrid and lower hybrid waves introduce the anomalous electron heating which results in the ionization enhancement and localized density ledge. The large-scale density irregularities formed in the heat flow, together with the density irregularities formed through the parametric instability, give rise to the enhanced virtual height spread. The results of upper hybrid instability analysis are also applied to explain the descending feature in the development of the artificial ionization layers observed in electron cyclotron harmonic resonance heating experiments.

  19. Isolated core vs. superficial cooling effects on virtual maze navigation.

    PubMed

    Payne, Jennifer; Cheung, Stephen S

    2007-07-01

    Cold impairs cognitive performance and is a common occurrence in many survival situations. Altered behavior patterns due to impaired navigation abilities in cold environments are potential problems in lost-person situations. We investigated the separate effects of low core temperature and superficial cooling on a spatially demanding virtual navigation task. There were 12 healthy men who were passively cooled via 15 degrees C water immersion to a core temperature of 36.0 degrees C, then transferred to a warm (40 degrees C) water bath to eliminate superficial shivering while completing a series of 20 virtual computer mazes. In a control condition, subjects rested in a thermoneutral (approximately 35 degrees C) bath for a time-matched period before being transferred to a warm bath for testing. Superficial cooling and distraction were achieved by whole-body immersion in 35 degree water for a time-matched period, followed by lower leg immersion in 10 degree C water for the duration of the navigational tests. Mean completion time and mean error scores for the mazes were not significantly different (p > 0.05) across the core cooling (16.59 +/- 11.54 s, 0.91 +/- 1.86 errors), control (15.40 +/- 8.85 s, 0.82 +/- 1.76 errors), and superficial cooling (15.19 +/- 7.80 s, 0.77 +/- 1.40 errors) conditions. Separately reducing core temperature or increasing cold sensation in the lower extremities did not influence performance on virtual computer mazes, suggesting that navigation is more resistive to cooling than other, simpler cognitive tasks. Further research is warranted to explore navigational ability at progressively lower core and skin temperatures, and in different populations.

  20. Illusion thermal device based on material with constant anisotropic thermal conductivity for location camouflage

    NASA Astrophysics Data System (ADS)

    Hou, Quanwen; Zhao, Xiaopeng; Meng, Tong; Liu, Cunliang

    2016-09-01

    Thermal metamaterials and devices based on transformation thermodynamics often require materials with anisotropic and inhomogeneous thermal conductivities. In this study, still based on the concept of transformation thermodynamics, we designed a planar illusion thermal device, which can delocalize a heat source in the device such that the temperature profile outside the device appears to be produced by a virtual source at another position. This device can be constructed by only one kind of material with constant anisotropic thermal conductivity. The condition which should be satisfied by the device is provided, and the required anisotropic thermal conductivity is then deduced theoretically. This study may be useful for the designs of metamaterials or devices since materials with constant anisotropic parameters have great facility in fabrication. A prototype device has been fabricated based on a composite composed by two naturally occurring materials. The experimental results validate the effectiveness of the device.

  1. A virtual-system coupled multicanonical molecular dynamics simulation: Principles and applications to free-energy landscape of protein-protein interaction with an all-atom model in explicit solvent

    NASA Astrophysics Data System (ADS)

    Higo, Junichi; Umezawa, Koji; Nakamura, Haruki

    2013-05-01

    We propose a novel generalized ensemble method, a virtual-system coupled multicanonical molecular dynamics (V-McMD), to enhance conformational sampling of biomolecules expressed by an all-atom model in an explicit solvent. In this method, a virtual system, of which physical quantities can be set arbitrarily, is coupled with the biomolecular system, which is the target to be studied. This method was applied to a system of an Endothelin-1 derivative, KR-CSH-ET1, known to form an antisymmetric homodimer at room temperature. V-McMD was performed starting from a configuration in which two KR-CSH-ET1 molecules were mutually distant in an explicit solvent. The lowest free-energy state (the most thermally stable state) at room temperature coincides with the experimentally determined native complex structure. This state was separated to other non-native minor clusters by a free-energy barrier, although the barrier disappeared with elevated temperature. V-McMD produced a canonical ensemble faster than a conventional McMD method.

  2. Top-seeded solution growth of SrTiO3 single crystals virtually free of mosaicity

    NASA Astrophysics Data System (ADS)

    Guguschev, Christo; Kok, Dirk J.; Juda, Uta; Uecker, Reinhard; Sintonen, Sakari; Galazka, Zbigniew; Bickermann, Matthias

    2017-06-01

    Strontium titanate (SrTiO3), a well-established traditional perovskite substrate as well as a promising substrate crystal for the epitaxy of new advanced perovskite-type thin films, suffers from the unavailability in adequate quality for the latter. To improve the situation attempts have been made to grow SrTiO3 at moderate temperatures (<1535 °C) well below the melting temperature and under low temperature gradients by the top-seeded solution growth method. Based on very special modifications of the growth conditions, virtually mosaicity-free SrTiO3 single crystals in the 1-2 cm range were obtained. High crystalline quality was verified by defect selective etching, rocking curve measurements, energy dispersive Laue mappings and by synchrotron X-Ray diffraction topography. The production of virtually subgrain- and dislocation free substrate crystals is essential to considerably improve characteristics of SrTiO3 based SQUIDs, transistors or memory devices and to allow an in-depth analysis of intrinsic and extrinsic factors influencing the properties of epitaxially grown oxide heterostructures.

  3. Interpreting Repeated Temperature-Depth Profiles for Groundwater Flow

    NASA Astrophysics Data System (ADS)

    Bense, Victor F.; Kurylyk, Barret L.; van Daal, Jonathan; van der Ploeg, Martine J.; Carey, Sean K.

    2017-10-01

    Temperature can be used to trace groundwater flows due to thermal disturbances of subsurface advection. Prior hydrogeological studies that have used temperature-depth profiles to estimate vertical groundwater fluxes have either ignored the influence of climate change by employing steady-state analytical solutions or applied transient techniques to study temperature-depth profiles recorded at only a single point in time. Transient analyses of a single profile are predicated on the accurate determination of an unknown profile at some time in the past to form the initial condition. In this study, we use both analytical solutions and a numerical model to demonstrate that boreholes with temperature-depth profiles recorded at multiple times can be analyzed to either overcome the uncertainty associated with estimating unknown initial conditions or to form an additional check for the profile fitting. We further illustrate that the common approach of assuming a linear initial temperature-depth profile can result in significant errors for groundwater flux estimates. Profiles obtained from a borehole in the Veluwe area, Netherlands in both 1978 and 2016 are analyzed for an illustrative example. Since many temperature-depth profiles were collected in the late 1970s and 1980s, these previously profiled boreholes represent a significant and underexploited opportunity to obtain repeat measurements that can be used for similar analyses at other sites around the world.

  4. MHD Equilibrium with Reversed Current Density and Magnetic Islands Revisited: the Vacuum Vector Potential Calculus

    NASA Astrophysics Data System (ADS)

    L. Braga, F.

    2013-10-01

    The solution of Grad-Shafranov equation determines the stationary behavior of fusion plasma inside a tokamak. To solve the equation it is necessary to know the toroidal current density profile. Recent works show that it is possible to determine a magnetohydrodynamic (MHD) equilibrium with reversed current density (RCD) profiles that presents magnetic islands. In this work we show analytical MHD equilibrium with a RCD profile and analyze the structure of the vacuum vector potential associated with these equilibria using the virtual casing principle.

  5. Improving the accuracy of the diagnosis of schizophrenia by means of virtual reality.

    PubMed

    Sorkin, Anna; Weinshall, Daphna; Modai, Ilan; Peled, Avi

    2006-03-01

    The authors' goal was to improve the diagnosis of schizophrenia by using virtual reality technology to build a complex, multimodal environment in which cognitive functions can be studied (and measured) in parallel. The authors studied sensory integration within working memory by means of computer navigation through a virtual maze. The simulated journey consisted of a series of rooms, each of which included three doors. Each door was characterized by three features (color, shape, and sound), and a single combination of features--the door-opening rule--was correct. Subjects had to learn the rule and use it. The participants were 39 schizophrenic patients and 21 healthy comparison subjects. Upon completion, each subject was assigned a performance profile, including various error scores, response time, navigation ability, and strategy. A classification procedure based on the subjects' performance profile correctly predicted 85% of the schizophrenic patients (and all of the comparison subjects). Several performance variables showed significant correlations with scores on a standard diagnostic measure (Positive and Negative Syndrome Scale), suggesting potential use of these measurements for the diagnosis of schizophrenia. On the other hand, the patients did not show unusual repetition of response despite stimulus cessation (called "perseveration" in classical studies of schizophrenia), which is a common symptom of the disease. This deficit appeared only when the subjects did not receive proper explanation of the task. The ability to study multimodal performance simultaneously by using virtual reality technology opens new possibilities for the diagnosis of schizophrenia with objective procedures.

  6. A pseudoenergy wave-activity relation for ageostrophic and non-hydrostatic moist atmosphere

    NASA Astrophysics Data System (ADS)

    Ran, Ling-Kun; Ping, Fan

    2015-05-01

    By employing the energy-Casimir method, a three-dimensional virtual pseudoenergy wave-activity relation for a moist atmosphere is derived from a complete system of nonhydrostatic equations in Cartesian coordinates. Since this system of equations includes the effects of water substance, mass forcing, diabatic heating, and dissipations, the derived wave-activity relation generalizes the previous result for a dry atmosphere. The Casimir function used in the derivation is a monotonous function of virtual potential vorticity and virtual potential temperature. A virtual energy equation is employed (in place of the previous zonal momentum equation) in the derivation, and the basic state is stationary but can be three-dimensional or, at least, not necessarily zonally symmetric. The derived wave-activity relation is further used for the diagnosis of the evolution and propagation of meso-scale weather systems leading to heavy rainfall. Our diagnosis of two real cases of heavy precipitation shows that positive anomalies of the virtual pseudoenergy wave-activity density correspond well with the strong precipitation and are capable of indicating the movement of the precipitation region. This is largely due to the cyclonic vorticity perturbation and the vertically increasing virtual potential temperature over the precipitation region. Project supported by the National Basic Research Program of China (Grant No. 2013CB430105), the Key Program of the Chinese Academy of Sciences (Grant No. KZZD-EW-05), the National Natural Science Foundation of China (Grant No. 41175060), and the Project of CAMS, China (Grant No. 2011LASW-B15).

  7. Velocity and temperature profiles in near-critical nitrogen flowing past a horizontal flat plate

    NASA Technical Reports Server (NTRS)

    Simoneau, R. J.

    1977-01-01

    Boundary layer velocity and temperature profiles were measured for nitrogen near its thermodynamic critical point flowing past a horizontal flat plate. The results were compared measurements made for vertically upward flow. The boundary layer temperatures ranged from below to above the thermodynamic critical temperature. For wall temperatures below the thermodynamic critical temperature there was little variation between the velocity and temperature profiles in three orientations. In all three orientations the point of crossing into the critical temperature region is marked by a significant flattening of the velocity and temperature profiles and also a decrease in heat transfer coefficient.

  8. A Backscatter-Lidar Forward-Operator

    NASA Astrophysics Data System (ADS)

    Geisinger, Armin; Behrendt, Andreas; Wulfmeyer, Volker; Vogel, Bernhard; Mattis, Ina; Flentje, Harald; Förstner, Jochen; Potthast, Roland

    2015-04-01

    We have developed a forward-operator which is capable of calculating virtual lidar profiles from atmospheric state simulations. The operator allows us to compare lidar measurements and model simulations based on the same measurement parameter: the lidar backscatter profile. This method simplifies qualitative comparisons and also makes quantitative comparisons possible, including statistical error quantification. Implemented into an aerosol-capable model system, the operator will act as a component to assimilate backscatter-lidar measurements. As many weather services maintain already networks of backscatter-lidars, such data are acquired already in an operational manner. To estimate and quantify errors due to missing or uncertain aerosol information, we started sensitivity studies about several scattering parameters such as the aerosol size and both the real and imaginary part of the complex index of refraction. Furthermore, quantitative and statistical comparisons between measurements and virtual measurements are shown in this study, i.e. applying the backscatter-lidar forward-operator on model output.

  9. 40 CFR 1066.950 - Fuel temperature profile.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Fuel temperature profile. 1066.950 Section 1066.950 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION... Test Procedures for Motor Vehicles § 1066.950 Fuel temperature profile. Develop fuel temperature...

  10. Investigation on the phenolic constituents in Hamamelis virginiana leaves by HPLC-DAD and LC-MS/MS.

    PubMed

    Duckstein, Sarina M; Stintzing, Florian C

    2011-08-01

    Aqueous and acetone/water extracts from Hamamelis virginiana leaves were investigated to obtain a thorough insight into their phenolic composition. To secure compound integrity, a gentle extraction method including the exclusion of light was used. Liquid chromatography tandem mass spectrometry (LC-MS/MS) analyses yielded a fingerprint including 27 phenolic constituents. Quantification of the key compounds on an equivalent basis by high-performance liquid chromatography diode-array detection (HPLC-DAD) showed that gallotannins consisting of six to 11 galloyl units constitute the main fraction, whereas procyanidins and catechin represented only a minor part. Closer inspection revealed that both extracts possess virtually the same galloyl hexose distribution, and the octagalloyl hexose represents the major tannin constituent. Additionally, eight flavonol glycosides and their corresponding aglycones quercetin and kaempferol, as well as three chlorogenic acid isomers and other hydroxycinnamic acids, were identified. Moreover, stability studies on the aqueous extract (5 °C, dark; room temperature, dark; room temperature, light) revealed that the phenolic profile underwent changes when exposed to light. Especially the gallotannins proved to be considerably unstable which may result in phytochemically altered Hamamelis leaf extracts upon transport and storage.

  11. Effects of Virtual Walking Treatment on Spinal Cord Injury-Related Neuropathic Pain: Pilot Results and Trends Related to Location of Pain and at-level Neuronal Hypersensitivity.

    PubMed

    Jordan, Melissa; Richardson, Elizabeth J

    2016-05-01

    Previous studies have shown that virtual walking to treat spinal cord injury-related neuropathic pain (SCI-NP) can be beneficial, although the type of SCI-NP that may benefit the most is unclear. This study's aims were to (1) determine the effect of location of SCI-NP on pain outcomes after virtual walking treatment and (2) examine the potential relationship between neuronal hyperexcitability, as measured by quantitative sensory testing, and pain reduction after virtual walking treatment. Participants were recruited from a larger ongoing trial examining the benefits of virtual walking in SCI-NP. Neuropathic pain was classified according to location of pain (at- or below-level). In addition, quantitative sensory testing was performed on a subset of individuals at a nonpainful area corresponding to the level of their injury before virtual walking treatment and was used to characterize treatment response. These pilot results suggest that when considered as a group, SCI-NP was responsive to treatment irrespective of the location of pain (F1, 44 = 4.82, P = 0.03), with a trend for the greatest reduction occurring in at-level SCI-NP (F1, 44 = 3.18, P = 0.08). These pilot results also potentially implicate cold, innocuous cool, and pressure hypersensitivity at the level of injury in attenuating the benefits of virtual walking to below-level pain, suggesting certain SCI-NP sensory profiles may be less responsive to virtual walking.

  12. Prediction based proactive thermal virtual machine scheduling in green clouds.

    PubMed

    Kinger, Supriya; Kumar, Rajesh; Sharma, Anju

    2014-01-01

    Cloud computing has rapidly emerged as a widely accepted computing paradigm, but the research on Cloud computing is still at an early stage. Cloud computing provides many advanced features but it still has some shortcomings such as relatively high operating cost and environmental hazards like increasing carbon footprints. These hazards can be reduced up to some extent by efficient scheduling of Cloud resources. Working temperature on which a machine is currently running can be taken as a criterion for Virtual Machine (VM) scheduling. This paper proposes a new proactive technique that considers current and maximum threshold temperature of Server Machines (SMs) before making scheduling decisions with the help of a temperature predictor, so that maximum temperature is never reached. Different workload scenarios have been taken into consideration. The results obtained show that the proposed system is better than existing systems of VM scheduling, which does not consider current temperature of nodes before making scheduling decisions. Thus, a reduction in need of cooling systems for a Cloud environment has been obtained and validated.

  13. Raman lidar/AERI PBL Height Product

    DOE Data Explorer

    Ferrare, Richard

    2012-12-14

    Planetary Boundary Layer (PBL) heights have been computed using potential temperature profiles derived from Raman lidar and AERI measurements. Raman lidar measurements of the rotational Raman scattering from nitrogen and oxygen are used to derive vertical profiles of potential temperature. AERI measurements of downwelling radiance are used in a physical retrieval approach (Smith et al. 1999, Feltz et al. 1998) to derive profiles of temperature and water vapor. The Raman lidar and AERI potential temperature profiles are merged to create a single potential temperature profile for computing PBL heights. PBL heights were derived from these merged potential temperature profiles using a modified Heffter (1980) technique that was tailored to the SGP site (Della Monache et al., 2004). PBL heights were computed on an hourly basis for the period January 1, 2009 through December 31, 2011. These heights are provided as meters above ground level.

  14. Self-similarity of temperature profiles in distant galaxy clusters: the quest for a universal law

    NASA Astrophysics Data System (ADS)

    Baldi, A.; Ettori, S.; Molendi, S.; Gastaldello, F.

    2012-09-01

    Context. We present the XMM-Newton temperature profiles of 12 bright (LX > 4 × 1044 erg s-1) clusters of galaxies at 0.4 < z < 0.9, having an average temperature in the range 5 ≲ kT ≲ 11 keV. Aims: The main goal of this paper is to study for the first time the temperature profiles of a sample of high-redshift clusters, to investigate their properties, and to define a universal law to describe the temperature radial profiles in galaxy clusters as a function of both cosmic time and their state of relaxation. Methods: We performed a spatially resolved spectral analysis, using Cash statistics, to measure the temperature in the intracluster medium at different radii. Results: We extracted temperature profiles for the clusters in our sample, finding that all profiles are declining toward larger radii. The normalized temperature profiles (normalized by the mean temperature T500) are found to be generally self-similar. The sample was subdivided into five cool-core (CC) and seven non cool-core (NCC) clusters by introducing a pseudo-entropy ratio σ = (TIN/TOUT) × (EMIN/EMOUT)-1/3 and defining the objects with σ < 0.6 as CC clusters and those with σ ≥ 0.6 as NCC clusters. The profiles of CC and NCC clusters differ mainly in the central regions, with the latter exhibiting a slightly flatter central profile. A significant dependence of the temperature profiles on the pseudo-entropy ratio σ is detected by fitting a function of r and σ, showing an indication that the outer part of the profiles becomes steeper for higher values of σ (i.e. transitioning toward the NCC clusters). No significant evidence of redshift evolution could be found within the redshift range sampled by our clusters (0.4 < z < 0.9). A comparison of our high-z sample with intermediate clusters at 0.1 < z < 0.3 showed how the CC and NCC cluster temperature profiles have experienced some sort of evolution. This can happen because higher z clusters are at a less advanced stage of their formation and did not have enough time to create a relaxed structure, which is characterized by a central temperature dip in CC clusters and by flatter profiles in NCC clusters. Conclusions: This is the first time that a systematic study of the temperature profiles of galaxy clusters at z > 0.4 has been attempted. We were able to define the closest possible relation to a universal law for the temperature profiles of galaxy clusters at 0.1 < z < 0.9, showing a dependence on both the relaxation state of the clusters and the redshift. Appendix A is only available in electronic form at http://www.aanda.org

  15. Integrating hinge axis approximation and the virtual facial simulation of prosthetic outcomes for treatment with CAD-CAM immediate dentures: A clinical report of a patient with microstomia.

    PubMed

    Kuric, Katelyn M; Harris, Bryan T; Morton, Dean; Azevedo, Bruno; Lin, Wei-Shao

    2017-09-29

    This clinical report describes a digital workflow using extraoral digital photographs and volumetric datasets from cone beam computed tomography (CBCT) imaging to create a 3-dimensional (3D), virtual patient with photorealistic appearance. In a patient with microstomia, hinge axis approximation, diagnostic casts simulating postextraction alveolar ridge profile, and facial simulation of prosthetic treatment outcome were completed in a 3D, virtual environment. The approach facilitated the diagnosis, communication, and patient acceptance of the treatment of maxillary and mandibular computer-aided design and computer-aided manufacturing (CAD-CAM) of immediate dentures at increased occlusal vertical dimension. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  16. Virtual photon emission from a quark-gluon plasma

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

    Suryanarayana, S. V.

    We present phenomenological formulas for virtual photon emission rates from a thermalized quark-gluon plasma (QGP) that include bremsstrahlung and annihilation with scattering (AWS) mechanisms along with the Landau-Pomeranchuk-Migdal (LPM) effects. For this purpose we follow the approach of generalized emission functions (GEF) for virtual photon emission, we showed earlier for a fixed temperature and strong coupling constant. In the present work, we extend the LPM calculations for several temperatures and strong coupling strengths, photon energies (q{sub 0}), photon mass (Q{sup 2}), and quark energies (p{sub 0}). We generalize the dynamical scaling variables, x{sub T},x{sub L}, for bremsstrahlung and AWS processesmore » that are now functions of variables p{sub 0},q{sub 0},Q{sup 2},T,{alpha}{sub s}. The GEF introduced earlier, g{sub T}{sup b},g{sub T}{sup a},g{sub L}{sup b},g{sub L}{sup a}, are also generalized for any temperatures and coupling strengths. From this, the imaginary part of the photon polarization tensor as a function of photon mass and energy has been calculated as a one-dimensional integral over these GEF and parton distribution functions in the plasma. By fitting these polarization tensors obtained from GEF method, we obtained a phenomenological formula for virtual photon emission rates as a function of (q{sub 0},Q{sup 2},T,{alpha}{sub s}) that includes bremsstrahlung and AWS mechanisms with LPM effects.« less

  17. Thirty Stage Annular Centrifugal Contactor Thermal Profile Measurements

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

    David H. Meikrantz; Troy G. Garn; Jack D. Law

    2010-02-01

    A thirty stage 5 cm annular centrifugal contactor cascade has been assembled and tested to obtain thermal profiles during both ambient and heated input conditions of operation. Thermocouples were installed on every stage as well as feed inputs and Real-time data was taken during experiments lasting from two to eight hours at total flow rates of 0.5 to 1.4 liters per minute. Ambient temperature profile results show that only a small amount of heat is generated by the mechanical energy of the contactors. Steady state temperature profiles mimic the ambient temperature of the lab but are higher toward the middlemore » of the cascade. Heated inlet solutions gave temperature profiles with smaller temperature gradients, more driven by the temperature of the inlet solutions than ambient lab temperature. Temperature effects of solution mixing, even at rotor speeds of 4000 rpm, were not measurable.« less

  18. Theoretical aspects of virtual simulators to train crews of fishing fleet

    NASA Astrophysics Data System (ADS)

    Lisitsyna, L.; Smetyuh, N.

    2018-05-01

    The use of virtual simulators is an important trend in the modern education, including the continuous training of specialists to meet the rapidly changing requirements for their qualification. Modern virtual simulators are multifunctional, i.e. they can be used to develop and enhance the skills as well as to control professional skills and abilities of specialists of diverse profiles under various working conditions. This study is based on the generalization of a large experience in the sphere of applying ready-made multifunctional virtual simulators (MFVS) and developing new ones for the training and retraining of the crews of the Azov-Black Sea fishing vessels. The results of the experimental studies of the MFVS "Fishing Simulator for Trawling and Purse Seining" show that at least 10 sessions are required to develop sustainable purse seining fishing skills. Almost all trainees (95%) successfully cope with the task within the time permitted by the standard requirements (three minutes) after 15 sessions.

  19. Profile analysis of after-effects experienced during exposure to several virtual reality environments

    NASA Technical Reports Server (NTRS)

    Kennedy, Robert S.; Jones, Marshall B.; Lilienthal, Michael G.; Harm, Deborah L.

    1994-01-01

    Motion sickness symptoms are an unwanted by-product of exposure to virtual environments. This problem is not new and was reported in the early flight simulators and experiments on ego motions and vection. The cardinal symptom of motion sickness is, of course, vomiting, but this symptom is ordinarily preceded by a variety of other symptoms. In his classic studies of motion sickness conducted before and during World War II, G. R. Wendt introduced a three point scale to score motion sickness beyond a vomit/no vomit dichotomy. Later, Navy scientists developed a Motion Sickness Questionnaire (MSQ), originally for use in a slowly rotating room. In the last 20 years the MSQ has been used in a series of studies of air, sea, and space sickness. Only recently, however, has it been appreciated that symptom patterns in the MSQ are not uniform but vary with the way sickness is induced. In seasickness, for example, nausea is the most prominent symptom. In Navy simulators, however, the most common symptom is eye strain, especially when cathode ray tubes are employed in the simulation. The latter result was obtained in a survey of over 1,500 pilot exposures. Using this database, Essex scientists conducted a factor analysis of the MSQ. We found that signs and symptoms of motion sickness fell mainly into three clusters: 1) oculomotor disturbance, 2) nausea and related neurovegetative problems, and 3) disorientation, ataxia, and vertigo. We have since rescored the MSQ results obtained in Navy simulators in terms of these three components. We have also compared these and other profiles obtained from three different vitual reality systems to profiles obtained in sea sickness, space sickness, and alcohol intoxication. We will show examples of these various profiles and point out simularities and differences among them which indicate aspects of what might be called 'virtual-reality sickness'.

  20. Adaptive neuro-fuzzy inference system for temperature and humidity profile retrieval from microwave radiometer observations

    NASA Astrophysics Data System (ADS)

    Ramesh, K.; Kesarkar, A. P.; Bhate, J.; Venkat Ratnam, M.; Jayaraman, A.

    2015-01-01

    The retrieval of accurate profiles of temperature and water vapour is important for the study of atmospheric convection. Recent development in computational techniques motivated us to use adaptive techniques in the retrieval algorithms. In this work, we have used an adaptive neuro-fuzzy inference system (ANFIS) to retrieve profiles of temperature and humidity up to 10 km over the tropical station Gadanki (13.5° N, 79.2° E), India. ANFIS is trained by using observations of temperature and humidity measurements by co-located Meisei GPS radiosonde (henceforth referred to as radiosonde) and microwave brightness temperatures observed by radiometrics multichannel microwave radiometer MP3000 (MWR). ANFIS is trained by considering these observations during rainy and non-rainy days (ANFIS(RD + NRD)) and during non-rainy days only (ANFIS(NRD)). The comparison of ANFIS(RD + NRD) and ANFIS(NRD) profiles with independent radiosonde observations and profiles retrieved using multivariate linear regression (MVLR: RD + NRD and NRD) and artificial neural network (ANN) indicated that the errors in the ANFIS(RD + NRD) are less compared to other retrieval methods. The Pearson product movement correlation coefficient (r) between retrieved and observed profiles is more than 92% for temperature profiles for all techniques and more than 99% for the ANFIS(RD + NRD) technique Therefore this new techniques is relatively better for the retrieval of temperature profiles. The comparison of bias, mean absolute error (MAE), RMSE and symmetric mean absolute percentage error (SMAPE) of retrieved temperature and relative humidity (RH) profiles using ANN and ANFIS also indicated that profiles retrieved using ANFIS(RD + NRD) are significantly better compared to the ANN technique. The analysis of profiles concludes that retrieved profiles using ANFIS techniques have improved the temperature retrievals substantially; however, the retrieval of RH by all techniques considered in this paper (ANN, MVLR and ANFIS) has limited success.

  1. Simultaneous virtual prediction of anti-Escherichia coli activities and ADMET profiles: A chemoinformatic complementary approach for high-throughput screening.

    PubMed

    Speck-Planche, Alejandro; Cordeiro, M N D S

    2014-02-10

    Escherichia coli remains one of the principal pathogens that cause nosocomial infections, medical conditions that are increasingly common in healthcare facilities. E. coli is intrinsically resistant to many antibiotics, and multidrug-resistant strains have emerged recently. Chemoinformatics has been a great ally of experimental methodologies such as high-throughput screening, playing an important role in the discovery of effective antibacterial agents. However, there is no approach that can design safer anti-E. coli agents, because of the multifactorial nature and complexity of bacterial diseases and the lack of desirable ADMET (absorption, distribution, metabolism, elimination, and toxicity) profiles as a major cause of disapproval of drugs. In this work, we introduce the first multitasking model based on quantitative-structure biological effect relationships (mtk-QSBER) for simultaneous virtual prediction of anti-E. coli activities and ADMET properties of drugs and/or chemicals under many experimental conditions. The mtk-QSBER model was developed from a large and heterogeneous data set of more than 37800 cases, exhibiting overall accuracies of >95% in both training and prediction (validation) sets. The utility of our mtk-QSBER model was demonstrated by performing virtual prediction of properties for the investigational drug avarofloxacin (AVX) under 260 different experimental conditions. Results converged with the experimental evidence, confirming the remarkable anti-E. coli activities and safety of AVX. Predictions also showed that our mtk-QSBER model can be a promising computational tool for virtual screening of desirable anti-E. coli agents, and this chemoinformatic approach could be extended to the search for safer drugs with defined pharmacological activities.

  2. Estimating the Soil Temperature Profile from a Single Depth Observation: A Simple Empirical Heatflow Solution

    NASA Technical Reports Server (NTRS)

    Holmes, Thomas; Owe, Manfred; deJeu, Richard

    2007-01-01

    Two data sets of experimental field observations with a range of meteorological conditions are used to investigate the possibility of modeling near-surface soil temperature profiles in a bare soil. It is shown that commonly used heat flow methods that assume a constant ground heat flux can not be used to model the extreme variations in temperature that occur near the surface. This paper proposes a simple approach for modeling the surface soil temperature profiles from a single depth observation. This approach consists of two parts: 1) modeling an instantaneous ground flux profile based on net radiation and the ground heat flux at 5cm depth; 2) using this ground heat flux profile to extrapolate a single temperature observation to a continuous near surface temperature profile. The new model is validated with an independent data set from a different soil and under a range of meteorological conditions.

  3. Atmospheric studies from the Mars Science Laboratory Entry, Descent and Landing atmospheric structure reconstruction

    NASA Astrophysics Data System (ADS)

    Holstein-Rathlou, C.; Maue, A.; Withers, P.

    2016-01-01

    The Mars Science Laboratory (MSL) entered the martian atmosphere on Aug. 6, 2012 landing in Gale crater (4.6°S, 137.4°E) in the local mid-afternoon. Aerodynamic accelerations were measured during descent and atmospheric density, pressure and temperature profiles have been calculated from this data. Using an averaging technique developed for the NASA Phoenix Mars mission, the profiles are extended to 134.1 km, twice that of the engineering reconstruction. Large-scale temperature oscillations in the MSL temperature profile are suggestive of thermal tides. Comparing the MSL temperature profile with measured Mars Climate Sounder temperature profiles and Mars Climate Database model output highlights the presence of diurnal tides. Derived vertical wavelengths for the diurnal migrating tide are larger than predicted from idealized tidal theory, indicating an added presence of nonmigrating diurnal tides. Sub-CO2 condensation mesospheric temperatures, very similar to the Pathfinder temperature profile, allude to the possibility of CO2 clouds. This is however not supported by recent observations and models.

  4. 2007 Campus Technology Innovators

    ERIC Educational Resources Information Center

    Campus Technology, 2007

    2007-01-01

    This article profiles the winners of this year's competition for outstanding technology innovation on US college and university campuses. The winners are: (1) Rice University, Texas (virtualized networks); (2) Drexel University, Pennsylvania (rich media); (3) Harvard Business School, Massachusetts (network management); (4) Louisiana State…

  5. Virtual Embryo: Systems Modeling in Developmental Toxicity

    EPA Science Inventory

    High-throughput screening (HTS) studies are providing a rich source of data that can be applied to chemical profiling to address sensitivity and specificity of molecular targets, biological pathways, cellular and developmental processes. EPA’s ToxCast project is testing 960 uniq...

  6. Correction of Electron Density Profiles in the Low Ionosphere Based on the Data of Vertical Sounding with the IRI Model

    NASA Astrophysics Data System (ADS)

    Denisenko, P. F.; Maltseva, O. A.; Sotsky, V. V.

    2018-03-01

    The method of correcting the daytime vertical profiles of electron plasma frequency in the low ionosphere from International Refererence Ionosphere (IRI) model in accordance with the measured data of the virtual heights and absorption of signal radiowaves (method A1) reflected from the bottom of E-region at vertical sounding (VS) is presented. The method is based on the replacement of the IRI model profile by an approximation of analytical dependence with parameters determined according to VS data and partially by the IRI model. The method is tested by the results of four joint ground-based and rocket experiments carried out in the 1970s at midlatitudes of the European part of Russia upon the launches of high-altitude geophysical rockets of the Vertical series. It is shown that the consideration of both virtual reflection heigths and absorption makes it possible to obtain electron density distributions that show the best agreement with the rocket measurements made at most height ranges in the D- and E-regions. In additional, the obtained distributions account more adequately than the IRI model for the contributions of D- and E-regions to absorption of signals reflected above these regions.

  7. Temperatures and aerosol opacities of the Mars atmosphere at aphelion: Validation and inter-comparison of limb sounding profiles from MRO/MCS and MGS/TES

    NASA Astrophysics Data System (ADS)

    Shirley, James H.; McConnochie, Timothy H.; Kass, David M.; Kleinböhl, Armin; Schofield, John T.; Heavens, Nicholas G.; McCleese, Daniel J.; Benson, Jennifer; Hinson, David P.; Bandfield, Joshua L.

    2015-05-01

    We exploit the relative stability and repeatability of the Mars atmosphere at aphelion for an inter-comparison of Mars Global Surveyor/Thermal Emission Spectrometer (MGS/TES) and Mars Reconnaissance Orbiter/Mars Climate Sounder (MRO/MCS) nighttime temperature profiles and aerosol opacity profiles in Mars years 25, 26, 29, 30, and 31. Cross-calibration of these datasets is important, as they together provide an extended climatology for this planetary atmosphere. As a standard of comparison we employ temperature profiles obtained by radio occultation methods during the MGS mission in Mars years 24, 25, and 26. We first compare both zonal mean TES limb sounding profiles and zonal mean MCS limb sounding profiles with zonal means of radio occultation temperature profiles for the same season (Ls = 70-80°) and latitudes (55-70°N). We employ a statistical z test for quantifying the degree of agreement of temperature profiles by pressure level. For pressures less than 610 Pa (altitudes > 3 km), the ensemble mean temperature difference between the radio occultation and TES limb sounding profiles found in these comparisons was 1.7 ± 0.7 K. The ensemble mean temperature difference between radio occultation and MCS profiles was 1.4 ± 1.0 K. These differences fall within the formal error estimates for both TES and MCS, validating the accuracy of the instruments and their respective retrieval algorithms. In the second phase of our investigation, we compare aphelion season zonal mean TES limb sounding temperature, water ice opacity, and dust opacity profiles with those obtained at the same latitudes in different years by MCS. The ensemble mean temperature difference found for three comparisons between TES and MCS zonal mean temperature profiles was 2.8 ± 2.1 K. MCS and TES temperatures between 610 Pa and 5 Pa from 55 to 70°N are largely in agreement (with differences < 2 K) when water ice aerosol opacities are comparable. Temperature differences increase when the opacities are dissimilar; TES profiles exhibit colder temperatures when TES water ice opacities are greater than those observed by MCS. Our comparisons reveal a possible systematic offset of TES and MCS temperatures at the highest altitudes resolved in the TES retrievals; TES temperatures are consistently colder than the corresponding MCS temperatures at pressures ⩽ 1 Pa (altitudes ⩾ 58 km). We otherwise find no evidence of systematic bias between TES limb sounding and MCS retrieved atmospheric quantities between 610 Pa and 1 Pa. Inter-annual variability is noted in comparisons of latitudinal temperature gradients from 55 to 70°N, in the amplitude of inversions linked with thermal tides in the middle atmosphere, and in the abundance and vertical distribution of water ice aerosols from 55 to 70°N during the aphelion season.

  8. Is physiotherapy integrated virtual walking effective on pain, function, and kinesiophobia in patients with non-specific low-back pain? Randomised controlled trial.

    PubMed

    Yilmaz Yelvar, Gul Deniz; Çırak, Yasemin; Dalkılınç, Murat; Parlak Demir, Yasemin; Guner, Zeynep; Boydak, Ayşenur

    2017-02-01

    According to literature, virtual reality was found to reduce pain and kinesiophobia in patients with chronic pain. The purpose of the study was to investigate short-term effect of the virtual reality on pain, function, and kinesiophobia in patients with subacute and chronic non-specific low-back pain METHODS: This randomised controlled study in which 44 patients were randomly assigned to the traditional physiotherapy (control group, 22 subjects) or virtual walking integrated physiotherapy (experimental group, 22 subjects). Before and after treatment, Visual Analog Scale (VAS), TAMPA Kinesiophobia Scale (TKS), Oswestry Disability Index (ODI), Nottingham Health Profile (NHP), Timed-up and go Test (TUG), 6-Minute Walk Test (6MWT), and Single-Leg Balance Test were assessed. The interaction effect between group and time was assessed by using repeated-measures analysis of covariance. After treatment, both groups showed improvement in all parameters. However, VAS, TKS, TUG, and 6MWT scores showed significant differences in favor of the experimental group. Virtual walking integrated physiotherapy reduces pain and kinesiophobia, and improved function in patients with subacute and chronic non-specific low-back pain in short term.

  9. Day-night variation in operationally retrieved TOVS temperature biases

    NASA Technical Reports Server (NTRS)

    Kidder, Stanley Q.; Achtemeier, Gary L.

    1986-01-01

    Several authors have reported that operationally retrieved TOVS (TIROS Operational Vertical Sounder) temperatures are biased with respect to rawinsonde temperatures or temperature analyses. This note reports a case study from which it is concluded that, at least for the time period Mar. 26 through Apr. 8, 1979, there was a significant day-night variation in TOVS mean layer virtual temperature biases with respect to objective analyses of rawinsonde data over the U.S.

  10. Electronic School.

    ERIC Educational Resources Information Center

    Executive Educator, 1994

    1994-01-01

    This issue of "The Electronic School" features a special forum on computer networking. Articles specifically focus on network operating systems, cabling requirements, and network architecture. Tom Wall argues that virtual reality is not yet ready for classroom use. B.J. Novitsky profiles two high schools experimenting with CD-ROM…

  11. Large-Eddy Simulations of Tropical Convective Systems, the Boundary Layer, and Upper Ocean Coupling

    DTIC Science & Technology

    2014-09-30

    warmer profile through greater latent heat release. Resulting temperature profiles all follow essentially moist adiabats in the upper troposphere ...default RRTM ozone concentration profile). Greater convective mixing deepens the tropopause for cases with stronger moisture flux convergence. Case...with tropospheric temperatures about 4 degrees cooler than the original temperature profile. This case represents conditions during the suppressed

  12. Thermal Buckling Analysis of Rectangular Panels Subjected to Humped Temperature Profile Heating

    NASA Technical Reports Server (NTRS)

    Ko, William I.

    2004-01-01

    This research investigates thermal buckling characteristics of rectangular panels subjected to different types of humped temperature profile heating. Minimum potential energy and finite-element methods are used to calculate the panel buckling temperatures. The two methods give fairly close thermal buckling solutions. 'Buckling temperature magnification factor of the first kind, eta' is established for the fixed panel edges to scale up the buckling solution of uniform temperature loading case to give the buckling solution of the humped temperature profile loading cases. Also, 'buckling temperature magnification factor of the second kind, xi' is established for the free panel edges to scale up the buckling solution of humped temperature profile loading cases with unheated boundary heat sinks to give the buckling solutions when the boundary heat sinks are heated up.

  13. Analytical and Experimental Study of Flow Through an Axial Turbine Stage with a Nonuniform Inlet Radial Temperature Profile

    NASA Technical Reports Server (NTRS)

    Schwab, J. R.; Stabe, R. G.; Whitney, W. J.

    1983-01-01

    Results are presented for a typical nonuniform inlet radial temperature profile through an advanced single-stage axial turbine and compared with the results obtained for a uniform profile. Gas temperature rises of 40 K to 95 K are predicted at the hub and tip corners at the trailing edges of the pressure surfaces in both the stator and rotor due to convection of hot fluid from the mean by the secondary flow. The inlet temperature profile is shown to be mixed out at the rotor exit survey plane (2.3 axial chords downstream of the rotor trailing edge) in both the analysis and the experiment. The experimental rotor exit angle profile for the nonuniform inlet temperature profile indicates underturning at the tip caused by increased clearance. Severe underturning also occurs at the mean, both with and without the nonuniform inlet temperature profile. The inviscid rotational flow code used in the analysis fails to predict the underturning at the mean, which may be caused by viscous effects.

  14. Analytical and experimental study of flow through an axial turbine stage with a nonuniform inlet radial temperature profile

    NASA Technical Reports Server (NTRS)

    Schwab, J. R.; Stabe, R. G.; Whitney, W. J.

    1983-01-01

    Results are presented for a typical nonuniform inlet radial temperature profile through an advanced single-stage axial turbine and compared with the results obtained for a uniform profile. Gas temperature rises of 40 K to 95 K are predicted at the hub and tip corners at the trailing edges of the pressure surfaces in both the stator and rotor due to convection of hot fluid from the mean by the secondary flow. The inlet temperature profile is shown to be mixed out at the rotor exit survey plane (2.3 axial chords downstream of the rotor trailing edge) in both the analysis and the experiment. The experimental rotor exit angle profile for the nonuniform inlet temperature profile indicates underturning at the tip caused by increased clearance. Severe underturning also occurs at the mean, both with and without the nonuniform inlet temperature profile. The inviscid rotational flow code used in the analysis fails to predict the underturning at the mean, which may be caused by viscous effects. Previously announced in STAR as N83-27958

  15. Mean state densities, temperatures and winds during the MAC/SINE and MAC/EPSILON campaigns

    NASA Technical Reports Server (NTRS)

    Luebken, F.-J.; Von Zahn, U.; Manson, A.; Meek, C.; Hoppe, U.-P.; Schmidlin, F. J.

    1990-01-01

    Two field campaigns were conducted, primarily in northern Norway, in the summer and late autumn of 1987; these yielded a total of 41 in situ temperature profiles and 67 in situ wind profiles. Simultaneously, ground-based measurements were conducted of OH temperatures and sodium lidar temperatures for 85 and 104 hours, respectively. The summer campaign's mean temperature profile exhibited major deviations from the CIRA (1986) reference atmosphere; the differences between this model and the observations are less pronounced in the autumn. Both the summer and autumn mean wind profiles were in general agreement with the CIRA model.

  16. Temperature profile and equipartition law in a Langevin harmonic chain

    NASA Astrophysics Data System (ADS)

    Kim, Sangrak

    2017-09-01

    Temperature profile in a Langevin harmonic chain is explicitly derived and the validity of the equipartition law is checked. First, we point out that the temperature profile in previous studies does not agree with the equipartition law: In thermal equilibrium, the temperature profile deviates from the same temperature distribution against the equipartition law, particularly at the ends of the chain. The matrix connecting temperatures of the heat reservoirs and the temperatures of the harmonic oscillators turns out to be a probability matrix. By explicitly calculating the power spectrum of the probability matrix, we will show that the discrepancy comes from the neglect of the power spectrum in higher frequency ω, which is in decay mode, and related with the imaginary number of wave number q.

  17. HEATPLOT: a temperature distribution plotting program for heating

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

    Elrod, D.C.; Turner, W.D.

    1977-07-01

    HEATPLOT is a temperature distribution plotting program that may be used with HEATING5, a generalized heat conduction code. HEATPLOT is capable of drawing temperature contours (isotherms), temperature-time profiles, and temperature-distance profiles from the current HEATING5 temperature distribution or from temperature changes relative to the initial temperature distribution. Contour plots may be made for two- or three-dimensional models. Temperature-time profiles and temperature-distance profiles may be made for one-, two-, and three-dimensional models. HEATPLOT is an IBM 360/370 computer code which uses the DISSPLA plotting package. Plots may be created on the CALCOMP pen-and-ink, and CALCOMP cathode ray tube (CRT), or themore » EAI pen-and-ink plotters. Printer plots may be produced or a compressed data set that may be routed to any of the available plotters may be made.« less

  18. Thermal structure of the Martian atmosphere retrieved from the IR- spectrometry in the 15 mkm CO2 band

    NASA Astrophysics Data System (ADS)

    Zasova, L.; Formisano, V.; Grassi, D.; Igantiev, N.; Moroz, V.

    Thermal IR spectrometry is one of the methods of the Martian atmosphere investigation below 55 km. The temperature profiles retrieved from the 15 μm CO2 band may be used for MIRA database. This approach gives the vertical resolution of several kilometers and accuracy of several Kelvins. An aerosol abundance, which influences the temperature profiles, is obtained from the continuum of the same spectrum. It is taken into account in the temperature retrieval procedure in a self- consistent way. Although this method has limited vertical resolution it possesses some advantages. For example, the radio occultation method gives the temperature profiles with higher spectral resolution, but the radio observations are sparse in space and local time. Direct measurements, which give the most accurate results, enable to obtain the temperature profiles only for some chosen points (landing places). Actually, the thermal IR-spectrometry is the only method, which allows to monitor the temperature profiles with good coverage both in space and local time. The first measurements of this kind were fulfilled by IRIS, installed on board of Mariner 9. This spectrometer was characterized by rather high spectral resolution (2.4 cm-1). The temperature profiles vs. local time dependencies for different latitudes and seasons were retrieved, including dust storm conditions, North polar night, Tharsis volcanoes. The obtained temperature profiles have been compared with the temperature profiles for the same conditions, taken from Climate Data Base (European GCM). The Planetary Fourier Spectrometer onboard Mars Express (which is planned to be launched in 2003) has the spectral range 1.2-45 μm and spectral resolution of 1.5 cm- 1. Temperature retrieval is one of the main scientific goals of the experiment. It opens a possibility to get a series of temperature profiles taken for different conditions, which can later be used in MIRA producing.

  19. Transient thermal analysis during friction stir welding between AA2014-T6 and pure copper

    NASA Astrophysics Data System (ADS)

    Gadhavi, A. R.; Ghetiya, N. D.; Patel, K. M.

    2018-04-01

    AA2xxx-Cu alloys showed larger applications in the defence sectors and in aerospace industries due to high strength to weight ratio and toughness. FSW in a butt joint configuration was carried out between AA2014-T6 and pure Copper placing AA2014 on AS and Cu on RS. Temperature profiles were observed by inserting K-type thermocouples in the mid-thickness at various locations of the plate. A sharp decrease in temperature profiles was observed on Copper side due to its higher thermal conductivity. A thermal numerical model was prepared in ANSYS to compare the simulated temperature profiles with the experimental temperature profiles and both the temperature profiles were found to be in good agreement.

  20. Laser beam shaping for studying thermally induced damage

    NASA Astrophysics Data System (ADS)

    Masina, Bathusile N.; Bodkin, Richard; Mwakikunga, Bonex; Forbes, Andrew

    2011-10-01

    This paper presents an implementation of a laser beam shaping system for both heating a diamond tool and measuring the resulting temperature optically. The influence the initial laser parameters have on the resultant temperature profiles is shown experimentally and theoretically. A CO2 laser beam was used as the source to raise the temperature of the diamond tool and the resultant temperature was measured by using the blackbody principle. We have successfully transformed a Gaussian beam profile into a flat-top beam profile by using a diffractive optical element as a phase element in conjunction with a Fourier transforming lens. In this paper, we have successfully demonstrated temperature profiles across the diamond tool surface using two laser beam profiles and two optical setups, thus allowing a study of temperature influences with and without thermal stress. The generation of such temperature profiles on the diamond tool in the laboratory is important in the study of changes that occur in diamond tools, particularly the reduced efficiency of such tools in applications where extreme heating due to friction is expected.

  1. Men are from Mars, women are from Venus? Examining gender differences in self-presentation on social networking sites.

    PubMed

    Haferkamp, Nina; Eimler, Sabrina C; Papadakis, Anna-Margarita; Kruck, Jana Vanessa

    2012-02-01

    Psychological research on gender differences in self-presentation has already revealed that women place higher priority on creating a positive self-presentation, while men are less concerned about the image they present in face-to-face (ftf) communication. Nowadays, with the extensive use of new media, self-presentation is no longer so closely tied to ftf situations, but can also take place in the online world. Specifically, social networking sites (SNS), such as Facebook or MySpace, offer various features such as profile pictures, groups, and virtual bulletin boards with which users can create elaborated online representations of themselves. What remains open is whether this virtual self-presentation on SNS is subject to gender differences. Based on studies emphasizing gender-related differences in Internet communication and behavior in general, it can be assumed that men and women have different motives regarding their SNS usage as well. A multimethodological study, combining results of an online survey and a content analysis of 106 user profiles, assessed users' diverse motives for participating in SNS in general, and their use of specific profile elements or self-presentation in particular. In this sample of StudiVZ users, women tend to be more likely to use SNS for comparing themselves with others and for searching for information. Men, on the other hand, are more likely to look at other people's profiles to find friends. Moreover, women tend to use group names for their self-presentation and prefer adding portrait photos to their profiles, while men choose full-body shots.

  2. Numerical study of effects of atmosphere temperature profile on wildfire behavior

    Treesearch

    Chunmei Xia; M. Yousuff Hussaini; Philip Cunningham; Rodman R. Linn; Scott L. Goodrick

    2003-01-01

    The vertical temperature profile and hence the stability in the atmosphere near the ground vanes significantly between day and night. Typically, the potential temperature at the surface is higher than that above the ground during the day and lower than that above the ground during the night. Such differences in the vertical temperature profile might act to accelerate...

  3. Prediction Based Proactive Thermal Virtual Machine Scheduling in Green Clouds

    PubMed Central

    Kinger, Supriya; Kumar, Rajesh; Sharma, Anju

    2014-01-01

    Cloud computing has rapidly emerged as a widely accepted computing paradigm, but the research on Cloud computing is still at an early stage. Cloud computing provides many advanced features but it still has some shortcomings such as relatively high operating cost and environmental hazards like increasing carbon footprints. These hazards can be reduced up to some extent by efficient scheduling of Cloud resources. Working temperature on which a machine is currently running can be taken as a criterion for Virtual Machine (VM) scheduling. This paper proposes a new proactive technique that considers current and maximum threshold temperature of Server Machines (SMs) before making scheduling decisions with the help of a temperature predictor, so that maximum temperature is never reached. Different workload scenarios have been taken into consideration. The results obtained show that the proposed system is better than existing systems of VM scheduling, which does not consider current temperature of nodes before making scheduling decisions. Thus, a reduction in need of cooling systems for a Cloud environment has been obtained and validated. PMID:24737962

  4. Incorporating Digisonde Traces into the Ionospheric Data Assimilation Three Dimensional (IDA3D) Algorithm

    DTIC Science & Technology

    2006-05-11

    examined. These data were processed by the Automatic Real Time Ionogram Scaler with True Height ( ARTIST ) [Reinisch and Huang, 1983] program into electron...IDA3D. The data is locally available and previously quality checked. In addition, IDA3D maps using ARTIST -calculated profiles from hand scaled...ionograms are available for comparison. The first test run of the IDA3D used only O-mode autoscaled virtual height profiles from five different digisondes

  5. Simulations of laser undulators

    NASA Astrophysics Data System (ADS)

    Milton, S. V.; Biedron, S. B.; Einstein, J. E.

    2016-09-01

    We perform a series of single-pass, one-D free-electron laser simulations based on an electron beam from a standard linear accelerator coupled with a so-called laser undulator, a specialized device that is more compact than a standard undulator based on magnetic materials. The longitudinal field profiles of such lasers undulators are intriguing as one must and can tailor the profile for the needs of creating the virtual undulator. We present and discuss several results of recent simulations and our future steps.

  6. Modeling limb-bud dysmorphogenesis in a predictive virtual embryo model

    EPA Science Inventory

    ToxCast is profiling the bioactivity of thousands of chemicals based on high-throughput screening (HTS) and computational methods that integrate knowledge of biological systems and in vivo toxicities (www.epa.gov/ncct/toxcast/). Many ToxCast assays assess signaling pathways and c...

  7. Expanding Opportunities for Students with Intellectual Disability

    ERIC Educational Resources Information Center

    Giangreco, Michael F.

    2017-01-01

    Research and experience tell us a great deal about how to successfully educate students with intellectual disability, but unfortunately this knowledge remains underutilized and inconsistently applied, writes researcher Michael F. Giangreco. Students with intellectual disability who have virtually identical profiles but live in different locales…

  8. Combined VHF Dopplar radar and airborne (CV-990) measurements of atmospheric winds on the mesoscale

    NASA Technical Reports Server (NTRS)

    Fairall, Christopher W.; Thomson, Dennis W.

    1989-01-01

    Hourly measurements of wind speed and direction obtained using two wind profiling Doppler radars during two prolonged jet stream occurrences over western Pennsylvania were analyzed. In particular, the time-variant characteristics of derived shear profiles were examined. To prevent a potential loss of structural detail and retain statistical significance, data from both radars were stratified into categories based on the location data from the Penn State radar were also compared to data from Pittsburgh radiosondes. Profiler data dropouts were studied in an attempt to determine possible reasons for the apparently reduced performance of profiling radars operating beneath a jet stream. Temperature profiles for the radar site were obtained using an interpolated temperature and dewpoint temperature sounding procedure developed at Penn State. The combination of measured wind and interpolated temperature profiles allowed Richardson number profiles to be generated for the profiler sounding volume. Both Richardson number and wind shear statistics were then examined along with pilot reports of turbulence in the vicinity of the profiler.

  9. Tropospheric profiles of wet refractivity and humidity from the combination of remote sensing data sets and measurements on the ground

    NASA Astrophysics Data System (ADS)

    Hurter, F.; Maier, O.

    2013-11-01

    We reconstruct atmospheric wet refractivity profiles for the western part of Switzerland with a least-squares collocation approach from data sets of (a) zenith path delays that are a byproduct of the GPS (global positioning system) processing, (b) ground meteorological measurements, (c) wet refractivity profiles from radio occultations whose tangent points lie within the study area, and (d) radiosonde measurements. Wet refractivity is a parameter partly describing the propagation of electromagnetic waves and depends on the atmospheric parameters temperature and water vapour pressure. In addition, we have measurements of a lower V-band microwave radiometer at Payerne. It delivers temperature profiles at high temporal resolution, especially in the range from ground to 3000 m a.g.l., though vertical information content decreases with height. The temperature profiles together with the collocated wet refractivity profiles provide near-continuous dew point temperature or relative humidity profiles at Payerne for the study period from 2009 to 2011. In the validation of the humidity profiles, we adopt a two-step procedure. We first investigate the reconstruction quality of the wet refractivity profiles at the location of Payerne by comparing them to wet refractivity profiles computed from radiosonde profiles available for that location. We also assess the individual contributions of the data sets to the reconstruction quality and demonstrate a clear benefit from the data combination. Secondly, the accuracy of the conversion from wet refractivity to dew point temperature and relative humidity profiles with the radiometer temperature profiles is examined, comparing them also to radiosonde profiles. For the least-squares collocation solution combining GPS and ground meteorological measurements, we achieve the following error figures with respect to the radiosonde reference: maximum median offset of relative refractivity error is -16% and quartiles are 5% to 40% for the lower troposphere. We further added 189 radio occultations that met our requirements. They mostly improved the accuracy in the upper troposphere. Maximum median offsets have decreased from 120% relative error to 44% at 8 km height. Dew point temperature profiles after the conversion with radiometer temperatures compare to radiosonde profiles as to: absolute dew point temperature errors in the lower troposphere have a maximum median offset of -2 K and maximum quartiles of 4.5 K. For relative humidity, we get a maximum mean offset of 7.3%, with standard deviations of 12-20%. The methodology presented allows us to reconstruct humidity profiles at any location where temperature profiles, but no atmospheric humidity measurements other than from GPS are available. Additional data sets of wet refractivity are shown to be easily integrated into the framework and strongly aid the reconstruction. Since the used data sets are all operational and available in near-realtime, we envisage the methodology of this paper to be a tool for nowcasting of clouds and rain and to understand processes in the boundary layer and at its top.

  10. Satellite-derived vertical profiles of temperature and dew point for mesoscale weather forecast

    NASA Astrophysics Data System (ADS)

    Masselink, Thomas; Schluessel, P.

    1995-12-01

    Weather forecast-models need spatially high resolutioned vertical profiles of temperature and dewpoint for their initialisation. These profiles can be supplied by a combination of data from the Tiros-N Operational Vertical Sounder (TOVS) and the imaging Advanced Very High Resolution Radiometer (AVHRR) on board the NOAA polar orbiting sate!- lites. In cloudy cases the profiles derived from TOVS data only are of insufficient accuracy. The stanthrd deviations from radiosonde ascents or numerical weather analyses likely exceed 2 K in temperature and 5Kin dewpoint profiles. It will be shown that additional cloud information as retrieved from AVHIRR allows a significant improvement in theaccuracy of vertical profiles. The International TOVS Processing Package (ITPP) is coupled to an algorithm package called AVHRR Processing scheme Over cLouds, Land and Ocean (APOLLO) where parameters like cloud fraction and cloud-top temperature are determined with higher accuracy than obtained from TOVS retrieval alone. Furthermore, a split-window technique is applied to the cloud-free AVHRR imagery in order to derive more accurate surface temperatures than can be obtained from the pure TOVS retrieval. First results of the impact of AVHRR cloud detection on the quality of the profiles are presented. The temperature and humidity profiles of different retrieval approaches are validated against analyses of the European Centre for Medium-Range Weatherforecasts.

  11. The effects of immersiveness on physiology.

    PubMed

    Wiederhold, B K; Davis, R; Wiederhold, M D

    1998-01-01

    The effects of varying levels of immersion in virtual reality environments on participant's heart rate, respiration rate, peripheral skin temperature, and skin resistance levels were examined. Subjective reports of presence were also noted. Participants were presented with a virtual environment of an airplane flight both as seen from a two-dimensional computer screen and as seen from within a head-mounted display. Subjects were randomly assigned to different order of conditions presented, but all subjects received both conditions. Differences between the non-phobics' physiological responses and the phobic's response when placed in a virtual environment related to the phobia were noted. Also noted were changes in physiology based on degree of immersion.

  12. Multisensor Retrieval of Atmospheric Properties.

    NASA Astrophysics Data System (ADS)

    Boba Stankov, B.

    1998-09-01

    A new method, Multisensor Retrieval of Atmospheric Properties (MRAP), is presented for deriving vertical profiles of atmospheric parameters throughout the troposphere. MRAP integrates measurements from multiple, diverse, remote sensing, and in situ instruments, the combination of which provides better capabilities than any instrument alone. Since remote sensors can deliver measurements automatically and continuously with high time resolution, MRAP provides better coverage than traditional rawinsondes. MRAP's design is flexible, being capable of incorporating measurements from different instruments in order to take advantage of new or developing advanced sensor technology. Furthermore, new or alternative atmospheric parameters for a variety of applications may be easily added as products of MRAP.A combination of passive radiometric, active radar, and in situ observations provide the best temperature and humidity profile measurements. Therefore, MRAP starts with a traditional, radiometer-based, physical retrieval algorithm provided by the International TOVS (TIROS-N Operational Vertical Sounder) Processing Package (ITPP) that constrains the retrieved profiles to agree with brightness temperature measurements. The first-guess profiles required by the ITPP's iterative retrieval algorithm are obtained by using a statistical inversion technique and ground-based remote sensing measurements. Because the individual ground-based remote sensing measurements are usually of sufficiently high quality, the first-guess profiles by themselves provide a satisfactory solution to establish the atmospheric water vapor and temperature state, and the TOVS data are included to provide profiles with better accuracy at higher levels, MRAP provides a physically consistent mechanism for combining the ground- and space-based humidity and temperature profiles.Data that have been used successfully to retrieve humidity and temperature profiles with MRAP are the following: temperature profiles in the lower troposphere from the ground-based Radio Acoustic Sounding System (RASS); total water vapor measurements from the Global Positioning System; specific humidity gradient profiles from the wind-profiling radar/RASS system; surface meteorological observations from standard instruments; cloud-base heights from a lidar ceilometer; temperature from the Aeronautical Radio, Incorporated Communication, Addressing and Reporting System aboard commercial airlines; and brightness temperature observations from TOVS.Data from the experiment conducted in the late summer of 1995 at Point Loma, California, were used for comparisons of MRAP results and 20 nearby rawinsonde releases to assess the statistical error estimates of MRAP. The temperature profiles had a bias of -0.27°C and a standard deviation of 1.56°C for the entire troposphere. Dewpoint profile retrievals did not have an overall accuracy as high as that of the temperature profiles but they exhibited a markedly improved standard deviation and bias in the lower atmosphere when the wind profiler/RASS specific humidity gradient information was available as a further constraint on the process. The European Centre for Medium-Range Weather Forecasts (ECMWF) model profiles of humidity and temperature for the grid point nearest to the Point Loma site were also used for comparison with the rawinsonde soundings to establish the usefulness of MRAP profiles to the weather forecasting community. The comparison showed that the vertical resolution of the ECMWF model profiles within the planetary boundary layer is not capable of detecting sharp gradients.

  13. Decoherence induced deformation of the ground state in adiabatic quantum computation.

    PubMed

    Deng, Qiang; Averin, Dmitri V; Amin, Mohammad H; Smith, Peter

    2013-01-01

    Despite more than a decade of research on adiabatic quantum computation (AQC), its decoherence properties are still poorly understood. Many theoretical works have suggested that AQC is more robust against decoherence, but a quantitative relation between its performance and the qubits' coherence properties, such as decoherence time, is still lacking. While the thermal excitations are known to be important sources of errors, they are predominantly dependent on temperature but rather insensitive to the qubits' coherence. Less understood is the role of virtual excitations, which can also reduce the ground state probability even at zero temperature. Here, we introduce normalized ground state fidelity as a measure of the decoherence-induced deformation of the ground state due to virtual transitions. We calculate the normalized fidelity perturbatively at finite temperatures and discuss its relation to the qubits' relaxation and dephasing times, as well as its projected scaling properties.

  14. Decoherence induced deformation of the ground state in adiabatic quantum computation

    PubMed Central

    Deng, Qiang; Averin, Dmitri V.; Amin, Mohammad H.; Smith, Peter

    2013-01-01

    Despite more than a decade of research on adiabatic quantum computation (AQC), its decoherence properties are still poorly understood. Many theoretical works have suggested that AQC is more robust against decoherence, but a quantitative relation between its performance and the qubits' coherence properties, such as decoherence time, is still lacking. While the thermal excitations are known to be important sources of errors, they are predominantly dependent on temperature but rather insensitive to the qubits' coherence. Less understood is the role of virtual excitations, which can also reduce the ground state probability even at zero temperature. Here, we introduce normalized ground state fidelity as a measure of the decoherence-induced deformation of the ground state due to virtual transitions. We calculate the normalized fidelity perturbatively at finite temperatures and discuss its relation to the qubits' relaxation and dephasing times, as well as its projected scaling properties. PMID:23528821

  15. Virtual Embryo: Systems Modeling in Developmental Toxicity

    EPA Science Inventory

    High-throughput and high-content screening (HTS-HCS) studies are providing a rich source of data that can be applied to in vitro profiling of chemical compounds for biological activity and potential toxicity. EPA’s ToxCast™ project, and the broader Tox21 consortium, in addition t...

  16. Modeling the disruption of vascular development in a Virtual Embryo using ToxCast HTS Bioactivity Profiles

    EPA Science Inventory

    Blood vessel formation is an important aspect of embryo development and teratogenesis. Recent studies address the signaling networks responsible for vasculogenesis and how they might be targeted by certain chemicals. For example, disruption of vasculogenesis and angiogenesis path...

  17. Effect of ambient temperature on the thermal profile of the human forearm, hand, and fingers

    NASA Technical Reports Server (NTRS)

    Montgomery, L. D.; Williams, B. A.

    1976-01-01

    Forearm, hand, and finger skin temperatures were measured on the right and left sides of seven resting men. The purpose was to determine the bilateral symmetry of these segmental temperature profiles at ambient temperatures from 10 to 45 C. Thermistors placed on the right and left forearms, hands, and index fingers were used to monitor the subjects until equilibration was reached at each ambient temperature. Additionally, thermal profiles of both hands were measured with copper-constantan thermocouples. During one experimental condition (23 C ambient), rectal, ear canal, and 24 skin temperatures were measured on each subject. Average body and average skin temperatures are given for each subject at the 23 C ambient condition. Detailed thermal profiles are also presented for the dorsal, ventral, and circumferential left forearm, hand, and finger skin temperatures at 23 C ambient. No significant differences were found between the mean skin temperatures of the right and left contralateral segments at any of the selected ambient temperatures.

  18. A new method to derive middle atmospheric temperature profiles using a combination of Rayleigh lidar and O2 airglow temperatures measurements

    NASA Astrophysics Data System (ADS)

    Taori, A.; Jayaraman, A.; Raghunath, K.; Kamalakar, V.

    2012-01-01

    The vertical temperature profiles in a typical Rayleigh lidar system depends on the backscatter photon counts and the CIRA-86 model inputs. For the first time, we show that, by making simultaneous measurements of Rayleigh lidar and upper mesospheric O2 temperatures, the lidar capability can be enhanced to obtain mesospheric temperature profile up to about 95 km altitudes. The obtained results are compared with instantaneous space-borne SABER measurements for a validation.

  19. Interactions of ( sup 3 H)amphetamine with rat brain synaptosomes. I. Saturable sequestration

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

    Zaczek, R.; Culp, S.; Goldberg, H.

    1991-05-01

    Previous studies have identified a saturable site of d-({sup 3}H)amphetamine sequestration (AMSEQ) in rat brain synaptosomes. The present study characterized AMSEQ with respect to its subcellular, neuronal and regional distributions, ontogenetic development, pharmacological specificity and factors required for its maintenance. Although AMSEQ was reduced when assays were performed in Krebs' buffer incubated at 37{degree}C as compared to assays performed in isotonic Tris-sucrose buffer incubated at room temperature, the pharmacological profiles of AMSEQ were virtually identical under both conditions. AMSEQ was negligible in tissues outside the central nervous system, enriched in synaptosomes and partially reduced by striatal kainic acid lesion, indicatingmore » neuronal localization. The distribution of AMSEQ in the central nervous system was heterogenous. Highest levels were present in hypothalamus with progressively lower levels noted in parietal cortex, frontal cortex, striatum, thalamus, hippocampus, midbrain, cerebellum, pons-medulla and spinal cord. With regard to its ontogeny, AMSEQ increased early in neonatal life, reaching adult levels by postnatal day 14. Although the effects of amphetamine to abolish the transynaptosomal pH gradient suggest a possible role for this gradient in the maintenance of AMSEQ, the pharmacological profile of AMSEQ indicates that other factors are involved. An interaction with an intrasynaptosomal acid, such as N-acetylaspartate, may account for AMSEQ maintenance. AMSEQ did not possess a stereospecific preference for either d-(IC50 = 177 microM) or I-amphetamine (IC50 = 173 microM). However, the pharmacological profile of AMSEQ indicated structural specificity with antidepressants being relatively potent inhibitors. (Abstract Truncated)« less

  20. A case study on the in silico absorption simulations of levothyroxine sodium immediate-release tablets.

    PubMed

    Kocic, Ivana; Homsek, Irena; Dacevic, Mirjana; Grbic, Sandra; Parojcic, Jelena; Vucicevic, Katarina; Prostran, Milica; Miljkovic, Branislava

    2012-04-01

    The aim of this case study was to develop a drug-specific absorption model for levothyroxine (LT4) using mechanistic gastrointestinal simulation technology (GIST) implemented in the GastroPlus™ software package. The required input parameters were determined experimentally, in silico predicted and/or taken from the literature. The simulated plasma profile was similar and in a good agreement with the data observed in the in vivo bioequivalence study, indicating that the GIST model gave an accurate prediction of LT4 oral absorption. Additionally, plasma concentration-time profiles were simulated based on a set of experimental and virtual in vitro dissolution data in order to estimate the influence of different in vitro drug dissolution kinetics on the simulated plasma profiles and to identify biorelevant dissolution specification for LT4 immediate-release (IR) tablets. A set of experimental and virtual in vitro data was also used for correlation purposes. In vitro-in vivo correlation model based on the convolution approach was applied in order to assess the relationship between the in vitro and in vivo data. The obtained results suggest that dissolution specification of more than 85% LT4 dissolved in 60 min might be considered as biorelevant dissolution specification criteria for LT4 IR tablets. Copyright © 2012 John Wiley & Sons, Ltd.

  1. Operational profiling of temperature using ground-based microwave radiometry at Payerne: prospects and challenges

    NASA Astrophysics Data System (ADS)

    Löhnert, U.; Maier, O.

    2012-05-01

    The motivation of this study is to verify theoretical expectations placed on ground-based microwave radiometer (MWR) techniques and to confirm whether they are suitable for supporting key missions of national weather services, such as timely and accurate weather advisories and warnings. We evaluate reliability and accuracy of atmospheric temperature profiles retrieved continuously by the microwave profiler system HATPRO (Humidity And Temperature PROfiler) operated at the aerological station of Payerne (MeteoSwiss) in the time period August 2006-December 2009. Assessment is performed by comparing temperatures from the radiometer against temperature measurements from a radiosonde accounting for a total of 2107 quality-controlled all-season cases. In the evaluated time period, the MWR delivered reliable temperature profiles in 86% of all-weather conditions on a temporal resolution of 12-13 min. Random differences between MWR and radiosonde are down to 0.5 K in the lower boundary layer and increase to 1.7 K at 4 km height. The differences observed between MWR and radiosonde in the lower boundary layer are similar to the differences observed between the radiosonde and another in-situ sensor located on a close-by 30 m tower. Temperature retrievals from above 4 km contain less than 5% of the total information content of the measurements, which makes clear that this technique is mainly suited for continuous observations in the boundary layer. Systematic temperature differences are also observed throughout the retrieved profile and can account for up to ±0.5 K. These errors are due to offsets in the measurements of the microwave radiances that have been corrected for in data post-processing and lead to nearly bias-free overall temperature retrievals. Different reasons for the radiance offsets are discussed, but cannot be unambiguously determined retrospectively. Monitoring and, if necessary, corrections for radiance offsets as well as a real-time rigorous automated data quality control are mandatory for microwave profiler systems that are designated for operational temperature profiling. In the analysis of a subset of different atmospheric situations, it is shown that lifted inversions and data quality during precipitation present the largest challenges for operational MWR temperature profiling.

  2. Temperature Profile Measurements in a Newly Constructed 30-Stage 5 cm Centrifugal Contactor pilot Plant

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

    Troy G. Garn; Dave H. Meikrantz; Mitchell R. Greenhalgh

    2008-09-01

    An annular centrifugal contactor pilot plant incorporating 30 stages of commercial 5 cm CINC V-02 units has been built and operated at INL during the past year. The pilot plant includes an automated process control and data acquisitioning system. The primary purpose of the pilot plant is to evaluate the performance of a large number of inter-connected centrifugal contactors and obtain temperature profile measurements within a 30-stage cascade. Additional solvent extraction flowsheet testing using stable surrogates is also being considered. Preliminary hydraulic testing was conducted with all 30 contactors interconnected for continuous counter-current flow. Hydraulic performance and system operational testsmore » were conducted successfully but with higher single-stage rotor speeds found necessary to maintain steady interstage flow at flowrates of 1 L/min and higher. Initial temperature profile measurements were also completed in this configuration studying the performance during single aqueous and two-phase counter-current flow at ambient and elevated inlet solution temperatures. Temperature profile testing of two discreet sections of the cascade required additional feed and discharge connections. Lamp oil, a commercially available alkane mixture of C14 to C18 chains, and tap water adjusted to pH 2 were the solution feeds for all the testing described in this report. Numerous temperature profiles were completed using a newly constructed 30-stage centrifugal contactor pilot plant. The automated process control and data acquisition system worked very well throughout testing. Temperature data profiles for an array of total flowrates (FT) and contactor rpm values for both single-phase and two-phase systems have been collected with selected profiles and comparisons reported. Total flowrates (FT) ranged from 0.5-1.4 L/min with rotor speeds from 3500-4000 rpm. Solution inlet temperatures ranging from ambient up to 50° C were tested. Ambient temperature testing shows that a small amount of heat is added to the processed solution by the mechanical energy of the contactors. The temperature profiles match the ambient temperature of the laboratory but are nearly 10° C higher toward the middle of the cascade. Heated input solution testing provides temperature profiles with smaller temperature gradients and are more influenced by the temperature of the inlet solutions than the ambient laboratory temperature. The temperature effects of solution mixing, even at 4000 rpm, were insignificant in any of the studies conducted on lamp oil and water.« less

  3. Measurement of temperature profiles in flames by emission-absorption spectroscopy

    NASA Technical Reports Server (NTRS)

    Simmons, F. S.; Arnold, C. B.; Lindquist, G. H.

    1972-01-01

    An investigation was conducted to explore the use of infrared and ultraviolet emission-absorption spectroscopy for determination of temperature profiles in flames. Spectral radiances and absorptances were measured in the 2.7-micron H2O band and the 3064-A OH band in H2/O2 flames for several temperature profiles which were directly measured by a sodium line-reversal technique. The temperature profiles, determined by inversion of the infrared and ultraviolet spectra, showed an average disagreement with line-reversal measurements of 50 K for the infrared and 200 K for the ultraviolet at a temperature of 2600 K. The reasons for these discrepancies are discussed in some detail.

  4. Commissioning of a Varian Clinac iX 6 MV photon beam using Monte Carlo simulation

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

    Dirgayussa, I Gde Eka, E-mail: ekadirgayussa@gmail.com; Yani, Sitti; Haryanto, Freddy, E-mail: freddy@fi.itb.ac.id

    2015-09-30

    Monte Carlo modelling of a linear accelerator is the first and most important step in Monte Carlo dose calculations in radiotherapy. Monte Carlo is considered today to be the most accurate and detailed calculation method in different fields of medical physics. In this research, we developed a photon beam model for Varian Clinac iX 6 MV equipped with MilleniumMLC120 for dose calculation purposes using BEAMnrc/DOSXYZnrc Monte Carlo system based on the underlying EGSnrc particle transport code. Monte Carlo simulation for this commissioning head LINAC divided in two stages are design head Linac model using BEAMnrc, characterize this model using BEAMDPmore » and analyze the difference between simulation and measurement data using DOSXYZnrc. In the first step, to reduce simulation time, a virtual treatment head LINAC was built in two parts (patient-dependent component and patient-independent component). The incident electron energy varied 6.1 MeV, 6.2 MeV and 6.3 MeV, 6.4 MeV, and 6.6 MeV and the FWHM (full width at half maximum) of source is 1 mm. Phase-space file from the virtual model characterized using BEAMDP. The results of MC calculations using DOSXYZnrc in water phantom are percent depth doses (PDDs) and beam profiles at depths 10 cm were compared with measurements. This process has been completed if the dose difference of measured and calculated relative depth-dose data along the central-axis and dose profile at depths 10 cm is ≤ 5%. The effect of beam width on percentage depth doses and beam profiles was studied. Results of the virtual model were in close agreement with measurements in incident energy electron 6.4 MeV. Our results showed that photon beam width could be tuned using large field beam profile at the depth of maximum dose. The Monte Carlo model developed in this study accurately represents the Varian Clinac iX with millennium MLC 120 leaf and can be used for reliable patient dose calculations. In this commissioning process, the good criteria of dose difference in PDD and dose profiles were achieve using incident electron energy 6.4 MeV.« less

  5. Scaling of confinement and profiles in the EXTRAP T2 reversed-field pinch

    NASA Astrophysics Data System (ADS)

    Welander, A.

    1999-01-01

    In the EXTRAP T2 reversed-field pinch the diagnostic techniques for the measurement of electron density and temperature include; Thomson scattering which gives values at three radial positions in the core (r/a = 0, 0.28, 0.56), Langmuir probes which give values at the edge (r/a > 0.9) and interferometry which gives a line-averaged density. The empirical scaling of electron density and temperature including profile information with global plasma parameters has been studied. The density profile is subject to large variations, with an average parabolic shape when the density is low and flatter shapes when the density is increased. The change in the profile shape can be attributed to a shift in the penetration length of neutrals from the vicinity of the wall. The temperature scales roughly as I/n1/2 where I is the plasma current and n is the density. The temperature profile is always quite flat with lower variations and there is a tendency for a flatter profile at higher temperatures.

  6. Comment on the paper "Mars Express radio occultation data: A novel analysis approach" by Grandin et al. (2014)

    NASA Astrophysics Data System (ADS)

    Pätzold, M.; Bird, M. K.; Häusler, B.; Peter, K.; Tellmann, S.; Tyler, G. L.

    2016-10-01

    In their recent paper, Grandin et al. (2014) claim to have developed a novel approach, principally a ray tracing method, to analyze radio sounding data from occulted spacecraft signals by planetary atmospheres without the usual assumptions of the radio occultation inversion method of a stratified, layered, symmetric atmosphere. They apply their "new approach" to observations of the Mars Express Radio Science (MaRS) experiment and compare their resulting temperature, neutral number density, and electron density profiles with those from MaRS, claiming that there is good agreement with the observations. The fact is, however, that there are serious disagreements in the most important altitude ranges. Their temperature profile shows a 30 K shift or a 300σ (1σ standard deviation = 0.1 K for the MaRS profile near the surface) difference toward warmer temperatures at the surface when compared with MaRS, while the MaRS profile is in best agreement with the profile from the Mars Climate Data Base V5.0 (MCD V5.0). Their full temperature profile from the surface to 250 km altitude deviates significantly from the MCD V5.0 profile. Their ionospheric electron density profile is considerably different from that derived from the MaRs observations. Although Grandin et al. (2014) claim to derive the neutral number density and temperature profiles above 200 km, including the asymptotic exosphere temperature, it is simply not possible to derive this information from what is essentially noise.

  7. Proactive Recruitment Strategies at CSUS Increase FCS Majors

    ERIC Educational Resources Information Center

    Malroutu, Y. Lakshmi; Tripp, Paula J.

    2008-01-01

    The profile and needs of today's undergraduate students have changed, and family and consumer sciences (FCS) departments will benefit from taking a proactive approach to adjust their recruitment strategies to meet those needs. California State University, Sacramento, implemented successful efforts in the areas of virtual contact, direct contact,…

  8. Story Lab: Student Data Privacy

    ERIC Educational Resources Information Center

    Herold, Benjamin

    2015-01-01

    Student data privacy is an increasingly high-profile--and controversial--issue that touches schools and families across the country. There are stories to tell in virtually every community. About three dozen states have passed legislation addressing student data privacy in the past two years, and eight different proposals were floating around…

  9. A Two-Temperature Model of the Intracluster Medium

    NASA Astrophysics Data System (ADS)

    Takizawa, Motokazu

    1998-12-01

    We investigate evolution of the intracluster medium (ICM), considering the relaxation process between the ions and electrons. According to the standard scenario of structure formation, the ICM is heated by the shock in the accretion flow to the gravitational potential well of the dark halo. The shock primarily heats the ions because the kinetic energy of an ion entering the shock is larger than that of an electron by the ratio of masses. Then the electrons and ions exchange the energy through Coulomb collisions and reach equilibrium. From simple order estimation we find that the region where the electron temperature is considerably lower than the ion temperature spreads out on a megaparsec scale. We then calculate the ion and electron temperature profiles by combining the adiabatic model of a two-temperature plasma by Fox & Loeb with spherically symmetric N-body and hydrodynamic simulations based on three different cosmological models. It is found that the electron temperature is about half the mean temperature at radii ~1 Mpc. This could lead to about a 50% underestimation in the total mass contained within ~1 Mpc when the electron temperature profiles are used. The polytropic indices of the electron temperature profiles are ~=1.5, whereas those of mean temperature are ~=1.3 for r >= 1 Mpc. This result is consistent both with the X-ray observations on electron temperature profiles and with some theoretical and numerical predictions about mean temperature profiles.

  10. Development of an Aircraft Approach and Departure Atmospheric Profile Generation Algorithm

    NASA Technical Reports Server (NTRS)

    Buck, Bill K.; Velotas, Steven G.; Rutishauser, David K. (Technical Monitor)

    2004-01-01

    In support of NASA Virtual Airspace Modeling and Simulation (VAMS) project, an effort was initiated to develop and test techniques for extracting meteorological data from landing and departing aircraft, and for building altitude based profiles for key meteorological parameters from these data. The generated atmospheric profiles will be used as inputs to NASA s Aircraft Vortex Spacing System (AVOLSS) Prediction Algorithm (APA) for benefits and trade analysis. A Wake Vortex Advisory System (WakeVAS) is being developed to apply weather and wake prediction and sensing technologies with procedures to reduce current wake separation criteria when safe and appropriate to increase airport operational efficiency. The purpose of this report is to document the initial theory and design of the Aircraft Approach Departure Atmospheric Profile Generation Algorithm.

  11. 40 CFR 86.133-96 - Diurnal emission test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... according to the profile specified in § 86.133 and appendix II of this part. (1) Temperatures measured with the underbody temperature sensor shall follow the profile with a maximum deviation of 3 °F at any time... temperature sensors shall follow the profile with a maximum deviation of 5 °F at any time. (2) Ambient...

  12. 40 CFR 86.1233-96 - Diurnal emission test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... according to the profile specified in § 86.1233 and appendix II of this part. (1) Temperatures measured with the underbody temperature sensor shall follow the profile with a maximum deviation of 3 °F at any time... temperature sensors shall follow the profile with a maximum deviation of 5 °F at any time. (2) Ambient...

  13. 40 CFR 86.133-96 - Diurnal emission test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... according to the profile specified in § 86.133 and appendix II of this part. (1) Temperatures measured with the underbody temperature sensor shall follow the profile with a maximum deviation of 3 °F at any time... temperature sensors shall follow the profile with a maximum deviation of 5 °F at any time. (2) Ambient...

  14. 40 CFR 86.1233-96 - Diurnal emission test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... according to the profile specified in § 86.1233 and appendix II of this part. (1) Temperatures measured with the underbody temperature sensor shall follow the profile with a maximum deviation of 3 °F at any time... temperature sensors shall follow the profile with a maximum deviation of 5 °F at any time. (2) Ambient...

  15. 40 CFR 86.133-96 - Diurnal emission test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... according to the profile specified in § 86.133 and appendix II of this part. (1) Temperatures measured with the underbody temperature sensor shall follow the profile with a maximum deviation of 3 °F at any time... temperature sensors shall follow the profile with a maximum deviation of 5 °F at any time. (2) Ambient...

  16. 40 CFR 86.1233-96 - Diurnal emission test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... according to the profile specified in § 86.1233 and appendix II of this part. (1) Temperatures measured with the underbody temperature sensor shall follow the profile with a maximum deviation of 3 °F at any time... temperature sensors shall follow the profile with a maximum deviation of 5 °F at any time. (2) Ambient...

  17. 40 CFR 86.133-96 - Diurnal emission test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... according to the profile specified in § 86.133 and appendix II of this part. (1) Temperatures measured with the underbody temperature sensor shall follow the profile with a maximum deviation of 3 °F at any time... temperature sensors shall follow the profile with a maximum deviation of 5 °F at any time. (2) Ambient...

  18. Temperature profiles from Salt Valley, Utah

    NASA Astrophysics Data System (ADS)

    Sass, J. H.; Lachenbruch, A. H.; Smith, E. P.

    Temperature profiles were obtained in the nine drilled wells as part of a thermal study of the Salt Valley anticline, Paradox Basin, Utha. Thermal conductivities were also measured on 10 samples judged to be representative of the rocks encountered in the deepest hole. The temperature profiles and thermal conductivities are presented, together with preliminary interpretive remarks and suggestions for additional work.

  19. Studies of long chain lipids in insects by high temperature gas chromatography and high temperature gas chromatography-mass spectrometry.

    PubMed

    Sutton, Paul A; Wilde, Michael J; Martin, Stephen J; Cvačka, Josef; Vrkoslav, Vladimír; Rowland, Steven J

    2013-07-05

    The organic compounds occurring naturally on the cuticles (surfaces) of insects are important for insect communication, help to act as protective water barriers and are useful in chemical taxonomy. Typically the cuticular lipids are only studied by gas chromatography-mass spectrometry (GC-MS) of hexane or pentane extracts, so the normal limitations of GC-MS makes it perhaps unsurprising that compounds with more than about 35 carbon atoms have only rarely been reported. Here we show by high temperature (HT) GC and HTGC-MS of extracts of eleven species of insects from nine genera, that longer chain compounds are actually common. Wax esters and triacylglycerides are virtually ubiquitous in such extracts, but long chain (>C35) hydrocarbons also sometimes occur. Whilst the latter have occasionally been reported previously from mass spectrometry studies, the use of the HTGC combination with MS allowed even some isobaric isomers to be separated and thus more complete lipid distributions to be monitored. Since the physical properties of cuticular compounds depend on this composition of the mixtures, such differences may influence the water loss rates of the insects, amongst other effects. In addition, the high molecular weight compound profiles may allow species to be more easily differentiated, one from another. It would be interesting to apply these methods to examination of the cuticular lipids of insects on a more routine basis, ideally in combination with MALDI-TOF-MS and imaging methods. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Multi-Scale Observation and Modelling of Energy and Matter Exchange in the Atmospheric Boundary-Layer (ScaleX Campaigns)

    NASA Astrophysics Data System (ADS)

    Zeeman, M. J.; Wolz, K.; Adler, B.; Brenner, C.; De Roo, F.; Emeis, S.; Kalthoff, N.; Mauder, M.; Schäfer, K.; Wohlfahrt, G.; Zhao, P.

    2016-12-01

    We investigated biosphere-atmosphere exchange processes in relation to the atmospheric boundary-layer (ABL) flow in a shallow valley. Land-use heterogeneity and topography can force local atmospheric flow patterns, including local circulations. Such flow patterns can impair current techniques for the quantification and source attribution of surface-exchange fluxes due to flux-divergence, advection and decoupling. Wind field, temperature and humidity structures in the ABL were observed in high resolution with spatially distributed observations in a 1 km3 experimental domain. Remote-sensing observations of wind, temperature and particles in the ABL (Raman-lidar; RASS; ceilometer; microwave radiometer; 3D Doppler-lidar) were combined with a high-resolution network of in-situ observations that included vertical and horizontal profiles of wind, temperature, carbon dioxide, methane and water vapor concentrations. The experiments were co-located with the long-term eddy covariance (EC) observatory Fendt (DE-Fen; ICOS, TERENO) and were part of international cooperative efforts in 2015 and 2016 (the ScaleX campaigns). The gathered experimental data offers a scale-transcending insight in local flow patterns in mountainous terrain and their influence on surface-exchange fluxes of energy and matter as observed by EC and flux-gradient methodology. In addition, the data is used for validation of Large-Eddy Simulations in complex terrain using PALM-LES. Within this modelling framework, virtual measurements are conducted to further assess the importance of three-dimensional advective and horizontal turbulent transport terms.

  1. Temperature control in a 30 stage, 5-cm Centrifugal Contactor Pilot Plant

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

    Jack D. Law; Troy G. Garn; David H. Meikrantz

    2009-09-01

    Temperature profile testing was performed using a 30 stage 5-cm centrifugal contactor pilot plant. These tests were performed to evaluate the ability to control process temperature by adjusting feed solution temperatures. This would eliminate the need for complex jacketed heat exchanger installation on the centrifugal contactors. Thermocouples were installed on the inlet and outlets of each stage, as well as directly in the mixing zone of several of the contactor stages. Lamp oil, a commercially available alkane mixture of C14 to C18 chains, and tap water adjusted to pH 2 with nitric acid were the solution feeds for the temperaturemore » profile testing. Temperature data profiles for an array of total throughputs and contactor rpm values for both single-phase and two-phase systems were collected with selected profiles. The total throughput ranged from 0.5-1.4 L/min with rotor speeds from 3500-4000 rpm. Inlet solution temperatures ranging from ambient up to 50 °C were tested. Results of the two-phase temperature profile testing are detailed« less

  2. Investigations of the internal wave characteristics and saturation degree in the Earth's atmosphere by using radiosonde measurements of wind and temperature and their applications to the RO wave studies

    NASA Astrophysics Data System (ADS)

    Kirillovich, Ivan; Gubenko, Vladimir; Pavelyev, Alexander

    Internal gravity waves (IGWs) affect the structure and circulation of the Earth’s atmosphere by transporting energy and momentum upward from lower atmosphere. Observations of the temperature and wind velocity fluctuations in the middle atmosphere have shown that wave amplitudes grow with increasing altitude, however, no quickly enough in order to correspond to amplitude growth due to exponential decrease of density in the absence of energy dissipation. The theory of saturated IGWs explains such rate of the wave amplitude growth in the following way: any wave amplitude in excess of the threshold value will lead to instability and the production of turbulence that acts to prevent further growth of the wave amplitude. The mechanisms that contribute most to the dissipation and saturation of the dominant IGW motions in the atmosphere are thought to be the dynamical (shear) and convective instability. For high-frequency waves, the threshold amplitude required to achieve shear instability is virtually identical to that required for convective instability. But for low-frequency IGWs, the shear instability threshold falls well below that necessary for convective instability. The knowledge of actual and threshold wave amplitudes is important when the effect of IGWs on the background atmosphere is to be assessed. The internal wave saturation assumption plays the key role for radio occultation (RO) investigations of IGWs in planetary atmospheres [Gubenko et al., 2008, 2011, 2012], therefore a radiosonde study of wave saturation processes in the Earth’s atmosphere is actual task. The results of determination of the actual and threshold amplitudes, saturation degree and other characteristics for identified IGWs in the Earth’s atmosphere found from high-resolution radiosonde measurements SPARC (http://www.sparc.sunysb.edu/) of horizontal wind and temperature are presented. The usefulness of these observations in conjunction with RO studies of IGWs is discussed. The work was carried out under partial support of the RFBR grant 13-02-00526-a and Program 22 of the RAS Presidium. References. Gubenko V.N., Pavelyev A.G., Andreev V.E. Determination of the intrinsic frequency and other wave parameters from a single vertical temperature or density profile measurement // J. Geophys. Res. 2008. V. 113. No.D08109, doi:10.1029/2007JD008920. Gubenko V.N., Pavelyev A.G., Salimzyanov R.R., Pavelyev A.A. Reconstruction of internal gravity wave parameters from radio occultation retrievals of vertical temperature profiles in the Earth’s atmosphere // Atmos. Meas. Tech. 2011. V. 4. No.10. P. 2153-2162, doi:10.5194/amt-4-2153-2011. Gubenko V.N., Pavelyev A.G., Salimzyanov R.R., Andreev V.E. A method for determination of internal gravity wave parameters from a vertical temperature or density profile measurement in the Earth’s atmosphere // Cosmic Res. 2012. V. 50. No.1. P. 21-31, doi: 10.1134/S0010952512010029.

  3. Radiation forcing by the atmospheric aerosols in the nocturnal boundary layer

    NASA Astrophysics Data System (ADS)

    Singh, D. K.; Ponnulakshami, V. K.; Mukund, V.; Subramanian, G.; Sreenivas, K. R.

    2013-05-01

    We have conducted experimental and theoretical studies on the radiation forcing due to suspended aerosols in the nocturnal boundary layer. We present radiative, conductive and convective equilibrium profile for different bottom boundaries where calculated Rayleigh number is higher than the critical Rayleigh number in laboratory conditions. The temperature profile can be fitted using an exponential distribution of aerosols concentration field. We also present the vertical temperature profiles in a nocturnal boundary in the presence of fog in the field. Our results show that during the presence of fog in the atmosphere, the ground temperature is greater than the dew-point temperature. The temperature profiles before and after the formation of fog are also observed to be different.

  4. Tokamak plasma current disruption infrared control system

    DOEpatents

    Kugel, Henry W.; Ulrickson, Michael

    1987-01-01

    In a magnetic plasma confinment device having an inner toroidal limiter mounted on an inner wall of a plasma containment vessel, an arrangement is provided for monitoring vertical temperature profiles of the limiter. The temperature profiles are taken at brief time intervals, in a time scan fashion. The time scans of the vertical temperature profile are continuously monitored to detect the presence of a peaked temperature excursion, which, according to the present invention, is a precursor of a subsequent major plasma disruption. A fast scan of the temperature profile is made so as to provide a time interval in real time prior to the major plasma disruption, such that corrective action can be taken to reduce the harmful effects of the plasma disruption.

  5. Temperature profiles of patient-applied eyelid warming therapies.

    PubMed

    Wang, Michael T M; Gokul, Akilesh; Craig, Jennifer P

    2015-12-01

    To compare temperature profile characteristics (on and off eye) of two patient-applied heat therapies for meibomian gland dysfunction (MGD): an eye mask containing disposable warming units (EyeGiene(®)) and a microwave-heated flaxseed eye bag(®) (MGDRx EyeBag(®)). In vitro evaluation: surface temperature profiles of activated eye masks and heated eye bags(®) (both n=10), were tracked every 10s until return to ambient temperature. Heat-transfer assessment: outer and inner eyelid temperature profiles throughout the eye mask and eye bag(®) treatment application period (10min) were investigated in triplicate. The devices were applied for 12 different time intervals in a randomised order, with a cool-down period in between to ensure ocular temperatures returned to baseline. Temperature measurements were taken before and immediately after each application. In vitro evaluation: on profile, the eye bag(®) surface temperature peaked earlier (0±0 s vs. 100±20 s, p<0.001), cooled more slowly and displayed less variability than the eye mask (all p<0.05). Heat-transfer assessment: the eye bag(®) effected higher peak inner eyelid temperatures (38.1±0.4°C vs. 37.4±0.2°C, p=0.04), as well as larger inner eyelid temperature increases over the first 2 min, and between 9 and 10 min (all p<0.05). The eye bag(®) surface temperature profile displayed greater uniformity and slower cooling than the eye mask, and was demonstrated to be significantly more effective in raising ocular temperatures than the eye mask, both statistically and clinically. This has implications for MGD treatment, where the melting points of meibomian secretions are likely to be higher with increasing disease severity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Relationship between perceived competence and performance during real and virtual motor tasks by children with developmental coordination disorder.

    PubMed

    Engel-Yeger, Batya; Sido, Rotem; Mimouni-Bloch, Aviva; Weiss, Patrice L

    2017-10-01

    (i) To compare children with DCD and typically developing participants via standard motor assessments, two interactive virtual games, measures of physical, social and cognitive self-competence and feedback while playing the virtual games and (ii) To examine the contribution of age and each motor assessment to predict self-competence. Participants were 25 boys with DCD and 25 typically developing boys, aged 5-9 years. They completed the M-ABC-2, the Pictorial Scale of Perceived Competence, the 6-Minute Walk Test, and then played the two Kinect games and completed the Short Feedback Questionnaire for Children. Children with DCD showed lower physical competence and lower performance than the typical controls in all standard motor assessments. This performance significantly correlated with the children achievements in part of virtual games and with their self-perceived experience while performing within virtual environments. Among the DCD group, Kinect Running game significantly predicted physical and social competence. The significant correlations between the virtual games and standard motor assessments support the feasibility of using these games when evaluating children with DCD for the richer profile they provide. Implications for rehabilitation Clinicians should refer to the impacts of DCD on child's self-competence and daily life. Technological rehabilitation and the use of VR games have the potential to improve self-competence of children with DCD. By including VR games that simulate real life in the intervention for DCD, clinicians may raise child's enjoyment, self-competence and involvement in therapy.

  7. Accuracy of virtual surgical planning in two-jaw orthognathic surgery: comparison of planned and actual results.

    PubMed

    Zhang, Nan; Liu, Shuguang; Hu, Zhiai; Hu, Jing; Zhu, Songsong; Li, Yunfeng

    2016-08-01

    This study aims to evaluate the accuracy of virtual surgical planning in two-jaw orthognathic surgery via quantitative comparison of preoperative planned and postoperative actual skull models. Thirty consecutive patients who required two-jaw orthognathic surgery were included. A composite skull model was reconstructed by using Digital Imaging and Communications in Medicine (DICOM) data from spiral computed tomography (CT) and STL (stereolithography) data from surface scanning of the dental arch. LeFort I osteotomy of the maxilla and bilateral sagittal split ramus osteotomy (of the mandible were simulated by using Dolphin Imaging 11.7 Premium (Dolphin Imaging and Management Solutions, Chatsworth, CA). Genioplasty was performed, if indicated. The virtual plan was then transferred to the operation room by using three-dimensional (3-D)-printed surgical templates. Linear and angular differences between virtually simulated and postoperative skull models were evaluated. The virtual surgical planning was successfully transferred to actual surgery with the help of 3-D-printed surgical templates. All patients were satisfied with the postoperative facial profile and occlusion. The overall mean linear difference was 0.81 mm (0.71 mm for the maxilla and 0.91 mm for the mandible); and the overall mean angular difference was 0.95 degrees. Virtual surgical planning and 3-D-printed surgical templates facilitated the diagnosis, treatment planning, and accurate repositioning of bony segments in two-jaw orthognathic surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Evaluating virtual hosted desktops for graphics-intensive astronomy

    NASA Astrophysics Data System (ADS)

    Meade, B. F.; Fluke, C. J.

    2018-04-01

    Visualisation of data is critical to understanding astronomical phenomena. Today, many instruments produce datasets that are too big to be downloaded to a local computer, yet many of the visualisation tools used by astronomers are deployed only on desktop computers. Cloud computing is increasingly used to provide a computation and simulation platform in astronomy, but it also offers great potential as a visualisation platform. Virtual hosted desktops, with graphics processing unit (GPU) acceleration, allow interactive, graphics-intensive desktop applications to operate co-located with astronomy datasets stored in remote data centres. By combining benchmarking and user experience testing, with a cohort of 20 astronomers, we investigate the viability of replacing physical desktop computers with virtual hosted desktops. In our work, we compare two Apple MacBook computers (one old and one new, representing hardware and opposite ends of the useful lifetime) with two virtual hosted desktops: one commercial (Amazon Web Services) and one in a private research cloud (the Australian NeCTAR Research Cloud). For two-dimensional image-based tasks and graphics-intensive three-dimensional operations - typical of astronomy visualisation workflows - we found that benchmarks do not necessarily provide the best indication of performance. When compared to typical laptop computers, virtual hosted desktops can provide a better user experience, even with lower performing graphics cards. We also found that virtual hosted desktops are equally simple to use, provide greater flexibility in choice of configuration, and may actually be a more cost-effective option for typical usage profiles.

  9. Carbon nanotube oscillator surface profiling device and method of use

    DOEpatents

    Popescu, Adrian [Tampa, FL; Woods, Lilia M [Tampa, FL; Bondarev, Igor V [Fuquay Varina, NC

    2011-11-15

    The proposed device is based on a carbon nanotube oscillator consisting of a finite length outer stationary nanotube and a finite length inner oscillating nanotube. Its main function is to measure changes in the characteristics of the motion of the carbon nanotube oscillating near a sample surface, and profile the roughness of this surface. The device operates in a non-contact mode, thus it can be virtually non-wear and non-fatigued system. It is an alternative to the existing atomic force microscope (AFM) tips used to scan surfaces to determine their roughness.

  10. RED: a set of molecular descriptors based on Renyi entropy.

    PubMed

    Delgado-Soler, Laura; Toral, Raul; Tomás, M Santos; Rubio-Martinez, Jaime

    2009-11-01

    New molecular descriptors, RED (Renyi entropy descriptors), based on the generalized entropies introduced by Renyi are presented. Topological descriptors based on molecular features have proven to be useful for describing molecular profiles. Renyi entropy is used as a variability measure to contract a feature-pair distribution composing the descriptor vector. The performance of RED descriptors was tested for the analysis of different sets of molecular distances, virtual screening, and pharmacological profiling. A free parameter of the Renyi entropy has been optimized for all the considered applications.

  11. Intercomparison Between Microwave Radiometer and Radiosonding Data

    NASA Astrophysics Data System (ADS)

    Toanca, Florica; Stefan, Sabina

    2014-05-01

    The aim of this study is to compare relative humidity and temperature vertical profiles measured by ground based Microwave Radiometer (MWR) RPG HATPRO installed at the Romanian Atmospheric Observatory (Magurele, 44.35 N, 26.03 E) and by radio-sounding (RS) (Baneasa, 44.30 N, 26.04 E) provided by National Meteorological Administration. MWR uses passive microwave detection in the 22.335 to 31.4 GHz and 51to 58 GHz bands to obtain the vertical profiles of temperature and relative humidity up to 10km with a temporal resolution of several minutes. The reliability of atmospheric temperature and relative humidity profiles retrieved continuously by the MWR for the winter and summer of year 2013 was studied. The study was conducted, comparing the temperature and humidity profiles from the MWR with the ones from the radio soundings at 0:00 a.m. Two datasets of the humidity show a fairly good agreement for the interval between ground and 1.5 km in the January month for winter and up to 2 km in the July month for summer. Above 2 km, for the both seasons, the humidity profiles present in most of the selected cases the same trend evolution. The temperature vertical profiles agreed in 95% of the cases during summer and 85% during winter. It is very important for intercomparison that for both seasons almost all temperature vertical profiles highlight temperature inversions. Two cases have been analyzed in order to find possible explanations for the discrepancies between vertical profiles, focusing on advantages and disadvantages of MWR measurements.

  12. Estimating Mixing Heights Using Microwave Temperature Profiler

    NASA Technical Reports Server (NTRS)

    Nielson-Gammon, John; Powell, Christina; Mahoney, Michael; Angevine, Wayne

    2008-01-01

    A paper describes the Microwave Temperature Profiler (MTP) for making measurements of the planetary boundary layer thermal structure data necessary for air quality forecasting as the Mixing Layer (ML) height determines the volume in which daytime pollution is primarily concentrated. This is the first time that an airborne temperature profiler has been used to measure the mixing layer height. Normally, this is done using a radar wind profiler, which is both noisy and large. The MTP was deployed during the Texas 2000 Air Quality Study (TexAQS-2000). An objective technique was developed and tested for estimating the ML height from the MTP vertical temperature profiles. In order to calibrate the technique and evaluate the usefulness of this approach, estimates from a variety of measurements during the TexAQS-2000 were compared. Estimates of ML height were used from radiosondes, radar wind profilers, an aerosol backscatter lidar, and in-situ aircraft measurements in addition to those from the MTP.

  13. Mesoscale temperature and moisture fields from satellite infrared soundings

    NASA Technical Reports Server (NTRS)

    Hillger, D. W.; Vonderhaar, T. H.

    1976-01-01

    The combined use of radiosonde and satellite infrared soundings can provide mesoscale temperature and moisture fields at the time of satellite coverage. Radiance data from the vertical temperature profile radiometer on NOAA polar-orbiting satellites can be used along with a radiosonde sounding as an initial guess in an iterative retrieval algorithm. The mesoscale temperature and moisture fields at local 9 - 10 a.m., which are produced by retrieving temperature profiles at each scan spot for the BTPR (every 70 km), can be used for analysis or as a forecasting tool for subsequent weather events during the day. The advantage of better horizontal resolution of satellite soundings can be coupled with the radiosonde temperature and moisture profile both as a best initial guess profile and as a means of eliminating problems due to the limited vertical resolution of satellite soundings.

  14. Differences between radiosonde and dropsonde temperature profiles over the Arctic Ocean

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

    Skony, S.M.; Kahl, J.D.W.; Zaitseva, N.A.

    1994-10-01

    The boundary layer structure measured by 402 pairs of approximately collocated radiosonde and dropsonde temperature profiles over the Arctic Ocean during the period 1957-1961 is examined. The radiosonde profiles were obtained at the Russian drifting ice camps `North Pole 7` and `North Pole 8,` and the dropsonde profiles were measured during the United States Air Force `Ptarmigan` series of weather reconnaissance flights. The boundary layer structure is characterized by the features of the low-level tropospheric temperature inversion. The results indicate that the dropsonde soundings, although containing relatively few measurement levels, contain sufficient vertical resolution to characterize the temperature inversion. Systematicmore » differences were noted in wintertime inversion features and near-surface temperatures as measured by dropsondes and radiosondes. These differences are attributed to contrasting temperature lag errors accompanying ascending and descending sensors.« less

  15. The YAK-AEROSIB transcontinental aircraft campaigns: new insights on the transport of CO2, CO and O3 across Siberia

    NASA Astrophysics Data System (ADS)

    Paris, J.-D.; Ciais, P.; Nédélec, P.; Ramonet, M.; Belan, B. D.; Arshinov, M. Yu.; Golitsyn, G. S.; Granberg, I.; Stohl, A.; Cayez, G.; Athier, G.; Boumard, F.; Cousin, J.-M.

    2008-09-01

    Two airborne campaigns were carried out to measure the tropospheric concentrations and variability of CO2, CO and O3 over Siberia. In order to quantify the influence of remote and regional natural and anthropogenic sources, we analysed a total of 52 vertical profiles of these species collected in April and September 2006, every ~200 km and up to 7 km altitude. CO2 and CO concentrations were high in April 2006 (respectively 385-390 ppm CO2 and 160-200 ppb CO) compared to background values. CO concentrations up to 220 ppb were recorded above 3.5 km over eastern Siberia, with enhancements in 500-1000 m thick layers. The presence of CO enriched air masses resulted from a quick frontal uplift of a polluted air mass exposed to northern China anthropogenic emissions and to fire emissions in northern Mongolia. A dominant Asian origin for CO above 4 km (71.0%) contrasted with a dominant European origin below this altitude (70.9%) was deduced both from a transport model analysis, and from the contrasted ΔCO/ΔCO2 ratio vertical distribution. In September 2006, a significant O3 depletion (~ -30 ppb) was repeatedly observed in the boundary layer, as diagnosed from virtual potential temperature profiles and CO2 gradients, compared to the free troposphere aloft, suggestive of a strong O3 deposition over Siberian forests.

  16. The High Accuracy Measurement of CO2 Mixing Ratio Profiles Using Ground Based 1.6 μm CO2-DIAL with Temperature Measurement Techniques in the Lower-Atmosphere

    NASA Astrophysics Data System (ADS)

    Abo, M.; Shibata, Y.; Nagasawa, C.

    2017-12-01

    We have developed a ground based direct detection three-wavelength 1.6 μm differential absorption lidar (DIAL) to achieve measurements of vertical CO2 concentration and temperature profiles in the atmosphere. As the spectra of absorption lines of any molecules are influenced basically by the temperature and pressure in the atmosphere, it is important to measure them simultaneously so that the better accuracy of the DIAL measurement is realized. Conventionally, we have obtained the vertical profile of absorption cross sections using the atmospheric temperature profile by the objective analysis and the atmospheric pressure profile calculated by the pressure height equation. Comparison of atmospheric pressure profiles calculated from this equation and those obtained from radiosonde observations at Tateno, Japan is consistent within 0.2 % below 3 km altitude. But the temperature dependency of the CO2 density is 0.25 %/°C near the surface. Moreover, the CO2 concentration is often evaluated by the mixing ratio. Because the air density is related by the ideal gas law, the mixing ratio is also related by the atmospheric temperature. Therefore, the temperature affects not only accuracy of CO2 concentration but the CO2 mixing ratio. In this paper, some experimental results of the simultaneous measurement of atmospheric temperature profiles and CO2 mixing ratio profiles are reported from 0.4 to 2.5 km altitude using the three-wavelength 1.6 μm DIAL system. Temperature profiles of CO2 DIAL measurement were sometimes different from those of objective analysis below 1.5 km altitude. These differences are considered to be due to regionality at the lidar site. The temperature difference of 5.0 °C corresponds to a CO2 mixing ratio difference of 8.0 ppm at 500 m altitude. This cannot be ignored in estimates of regional sources and sinks of CO2. This three-wavelength CO2 DIAL technique can estimate accurately temporal behavior of CO2 mixing ratio profiles in the lower atmosphere. This work was financially supported by the System Development Program for Advanced Measurement and Analysis of the Japan Science and Technology Agency.

  17. Effects of Temperature and Air Density Profiles on Ozone Lidar Retrievals

    NASA Astrophysics Data System (ADS)

    Kirgis, G.; Langford, A. O.; Senff, C. J.; Alvarez, R. J. _II, II

    2017-12-01

    The recent reduction in the primary U.S. National Ambient Air Quality Standard (NAAQS) for ozone (O3) from 75 to 70 parts-per-billion by volume (ppbv) adds urgency to the need for better understanding of the processes that control ground-level concentrations in the United States. While ground-based in situ sensors are capable of measuring ozone levels, they don't give any insight into upper air transport and mixing. Differential absorption lidars such as the NOAA/ESRL Tunable Optical Profiler for Aerosol and oZone (TOPAZ) measure continuous vertical ozone profiles with high spatial and temporal resolution. However, the retrieved ozone mixing ratios depend on the temperature and air density profiles used in the analysis. This study analyzes the ozone concentrations for seven field campaigns from 2013 to 2016 to evaluate the impact of the assumed pressure and temperature profiles on the ozone mixing ratio retrieval. Pressure and temperature profiles from various spatial and temporal resolution models (Modern Era Retrospective-Analysis for Research and Applications, NCEP/NCAR Reanalysis, NCEP North American Regional Reanalysis, Rapid Refresh, and High-Resolution Rapid Refresh) are compared to reference ozone profiles created with pressure and temperature profiles from ozonesondes launched close to the TOPAZ measurement site. The results show significant biases with respect to time of day and season, altitude, and location of the model-extracted profiles. Limitations and advantages of all datasets used will also be discussed.

  18. Assessment of Mars Atmospheric Temperature Retrievals from the Thermal Emission Spectrometer Radiances

    NASA Technical Reports Server (NTRS)

    Hoffman, Matthew J.; Eluszkiewicz, Janusz; Weisenstein, Deborah; Uymin, Gennady; Moncet, Jean-Luc

    2012-01-01

    Motivated by the needs of Mars data assimilation. particularly quantification of measurement errors and generation of averaging kernels. we have evaluated atmospheric temperature retrievals from Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) radiances. Multiple sets of retrievals have been considered in this study; (1) retrievals available from the Planetary Data System (PDS), (2) retrievals based on variants of the retrieval algorithm used to generate the PDS retrievals, and (3) retrievals produced using the Mars 1-Dimensional Retrieval (M1R) algorithm based on the Optimal Spectral Sampling (OSS ) forward model. The retrieved temperature profiles are compared to the MGS Radio Science (RS) temperature profiles. For the samples tested, the M1R temperature profiles can be made to agree within 2 K with the RS temperature profiles, but only after tuning the prior and error statistics. Use of a global prior that does not take into account the seasonal dependence leads errors of up 6 K. In polar samples. errors relative to the RS temperature profiles are even larger. In these samples, the PDS temperature profiles also exhibit a poor fit with RS temperatures. This fit is worse than reported in previous studies, indicating that the lack of fit is due to a bias correction to TES radiances implemented after 2004. To explain the differences between the PDS and Ml R temperatures, the algorithms are compared directly, with the OSS forward model inserted into the PDS algorithm. Factors such as the filtering parameter, the use of linear versus nonlinear constrained inversion, and the choice of the forward model, are found to contribute heavily to the differences in the temperature profiles retrieved in the polar regions, resulting in uncertainties of up to 6 K. Even outside the poles, changes in the a priori statistics result in different profile shapes which all fit the radiances within the specified error. The importance of the a priori statistics prevents reliable global retrievals based a single a priori and strongly implies that a robust science analysis must instead rely on retrievals employing localized a priori information, for example from an ensemble based data assimilation system such as the Local Ensemble Transform Kalman Filter (LETKF).

  19. Clay aquitards as archives of holocene paleoclimate: delta18O and thermal profiling.

    PubMed

    Hendry, M Jim; Woodbury, A D

    2007-01-01

    Paleoclimatic conditions in the Holocene were reconstructed from a detailed vertical profile of pore water delta(18)O and a series of downhole thermal profiles at a thick, hydrogeologically simple, aquitard research site in the Northern Great Plains of Saskatchewan. Reconstructions were obtained using the theory of one-dimensional diffusive transport and an empirical Bayesian inversion technique. Inversion of the delta(18)O profile shows that input signal consists of a sudden increase of +6 per thousand (corresponding to a temperature increase of about 18 degrees C) at about 12,000 years before present (BP), after which no measurable change in delta(18)O is apparent to present day. This research shows, at this location, that there is no evidence of large amplitude temperature shifts in the Holocene and supports the commonly used assumption in ground water studies of constant atmospheric delta(18)O values throughout the Holocene. Inversion of the temperature profiles suggests the ground surface temperature increased primarily in the last half of the 20th century, with a peak temperature (about 3 degrees C) circa 1990. For both profiles, the ability to resolve historical variability decays rapidly with time. For the temperature profiles, the decay in resolution precluded the development of reliable estimates of climatic conditions prior to about 1950 and, in the case of the delta(18)O profile, it prevented the precise definition of climate changes (e.g., Hypsithermal and Little Ice Age) in the Holocene.

  20. A single field of view method for retrieving tropospheric temperature profiles from cloud-contaminated radiance data

    NASA Technical Reports Server (NTRS)

    Hodges, D. B.

    1976-01-01

    An iterative method is presented to retrieve single field of view (FOV) tropospheric temperature profiles directly from cloud-contaminated radiance data. A well-defined temperature profile may be calculated from the radiative transfer equation (RTE) for a partly cloudy atmosphere when the average fractional cloud amount and cloud-top height for the FOV are known. A cloud model is formulated to calculate the fractional cloud amount from an estimated cloud-top height. The method is then examined through use of simulated radiance data calculated through vertical integration of the RTE for a partly cloudy atmosphere using known values of cloud-top height(s) and fractional cloud amount(s). Temperature profiles are retrieved from the simulated data assuming various errors in the cloud parameters. Temperature profiles are retrieved from NOAA-4 satellite-measured radiance data obtained over an area dominated by an active cold front and with considerable cloud cover and compared with radiosonde data. The effects of using various guessed profiles and the number of iterations are considered.

  1. Community-level physiological profiles of bacteria and fungi: Plate type and incubation temperature influences on contrasting soils

    Treesearch

    Aimee T. Classen; Sarah I. Boyle; Kristin E. Haskins; Steven T. Overby; Stephen C. Hart

    2003-01-01

    Temperature sensitivity of community-level physiological profiles (CLPPs) was examined for two semiarid soils from the southwestern United States using five different C-substrate profile microtiter plates (Biolog GN2, GP2, ECO, SFN2, and SFP2) incubated at five different temperature regimes.The CLPPs produced from all plate types were relatively unaffected by these...

  2. The effects of temperatures on the pebble flow in a pebble bed high temperature reactor

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

    Sen, R. S.; Cogliati, J. J.; Gougar, H. D.

    2012-07-01

    The core of a pebble bed high temperature reactor (PBHTR) moves during operation, a feature which leads to better fuel economy (online refueling with no burnable poisons) and lower fuel stress. The pebbles are loaded at the top and trickle to the bottom of the core after which the burnup of each is measured. The pebbles that are not fully burned are recirculated through the core until the target burnup is achieved. The flow pattern of the pebbles through the core is of importance for core simulations because it couples the burnup distribution to the core temperature and power profiles,more » especially in cores with two or more radial burnup 'zones '. The pebble velocity profile is a strong function of the core geometry and the friction between the pebbles and the surrounding structures (other pebbles or graphite reflector blocks). The friction coefficient for graphite in a helium environment is inversely related to the temperature. The Thorium High Temperature Reactor (THTR) operated in Germany between 1983 and 1989. It featured a two-zone core, an inner core (IC) and outer core (OC), with different fuel mixtures loaded in each zone. The rate at which the IC was refueled relative to the OC in THTR was designed to be 0.56. During its operation, however, this ratio was measured to be 0.76, suggesting the pebbles in the inner core traveled faster than expected. It has been postulated that the positive feedback effect between inner core temperature, burnup, and pebble flow was underestimated in THTR. Because of the power shape, the center of the core in a typical cylindrical PBHTR operates at a higher temperature than the region next to the side reflector. The friction between pebbles in the IC is lower than that in the OC, perhaps causing a higher relative flow rate and lower average burnup, which in turn yield a higher local power density. Furthermore, the pebbles in the center region have higher velocities than the pebbles next to the side reflector due to the interaction between the pebbles and the immobile graphite reflector as well as the geometry of the discharge conus near the bottom of the core. In this paper, the coupling between the temperature profile and the pebble flow dynamics was analyzed by using PEBBED/THERMIX and PEBBLES codes by modeling the HTR-10 reactor in China. Two extreme and opposing velocity profiles are used as a starting point for the iterations. The PEBBED/THERMIX code is used to calculate the burnup, power and temperature profiles with one of the velocity profiles as input. The resulting temperature profile is then passed to PEBBLES code to calculate the updated pebble velocity profile taking the new temperature profile into account. If the aforementioned hypothesis is correct, the strong temperature effect upon the friction coefficients would cause the two cases to converge to different final velocity and temperature profiles. The results of this analysis indicates that a single zone pebble bed core is self-stabilizing in terms of the pebble velocity profile and the effect of the temperature profile on the pebble flow is insignificant. (authors)« less

  3. Blended Identities: Identity Work, Equity and Marginalization in Blended Learning

    ERIC Educational Resources Information Center

    Heikoop, Will

    2013-01-01

    This article is a theoretical study of the self-presentation strategies employed by higher education students online; it examines student identity work via profile information and avatars in a blended learning environment delivered through social networking sites and virtual worlds. It argues that students are faced with difficult choices when…

  4. Choosing the Right Free IM Providers and Clients for Your Library

    ERIC Educational Resources Information Center

    Izenstark, Amanda K.

    2009-01-01

    With virtual library services increasing, public services librarians may find themselves with questions such as: What instant messaging services (IM) are available? Which IM service would best suit my patrons' needs? Which IM service best suits my library's technology profile? This column describes the features and functionality of major instant…

  5. Virtual Clinical Trial Toward Polytherapy Safety Assessment: Combination of Physiologically Based Pharmacokinetic/Pharmacodynamic-Based Modeling and Simulation Approach With Drug-Drug Interactions Involving Terfenadine as an Example.

    PubMed

    Wiśniowska, Barbara; Polak, Sebastian

    2016-11-01

    A Quantitative Systems Pharmacology approach was utilized to predict the cardiac consequences of drug-drug interaction (DDI) at the population level. The Simcyp in vitro-in vivo correlation and physiologically based pharmacokinetic platform was used to predict the pharmacokinetic profile of terfenadine following co-administration of the drug. Electrophysiological effects were simulated using the Cardiac Safety Simulator. The modulation of ion channel activity was dependent on the inhibitory potential of drugs on the main cardiac ion channels and a simulated free heart tissue concentration. ten Tusscher's human ventricular cardiomyocyte model was used to simulate the pseudo-ECG traces and further predict the pharmacodynamic consequences of DDI. Consistent with clinical observations, predicted plasma concentration profiles of terfenadine show considerable intra-subject variability with recorded C max values below 5 ng/mL for most virtual subjects. The pharmacokinetic and pharmacodynamic effects of inhibitors were predicted with reasonable accuracy. In all cases, a combination of the physiologically based pharmacokinetic and physiology-based pharmacodynamic models was able to differentiate between the terfenadine alone and terfenadine + inhibitor scenario. The range of QT prolongation was comparable in the clinical and virtual studies. The results indicate that mechanistic in vitro-in vivo correlation can be applied to predict the clinical effects of DDI even without comprehensive knowledge on all mechanisms contributing to the interaction. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  6. Pervasive Radio Mapping of Industrial Environments Using a Virtual Reality Approach

    PubMed Central

    Nedelcu, Adrian-Valentin; Machedon-Pisu, Mihai; Talaba, Doru

    2015-01-01

    Wireless communications in industrial environments are seriously affected by reliability and performance issues, due to the multipath nature of obstacles within such environments. Special attention needs to be given to planning a wireless industrial network, so as to find the optimum spatial position for each of the nodes within the network, and especially for key nodes such as gateways or cluster heads. The aim of this paper is to present a pervasive radio mapping system which captures (senses) data regarding the radio spectrum, using low-cost wireless sensor nodes. This data is the input of radio mapping algorithms that generate electromagnetic propagation profiles. Such profiles are used for identifying obstacles within the environment and optimum propagation pathways. With the purpose of further optimizing the radio planning process, the authors propose a novel human-network interaction (HNI) paradigm that uses 3D virtual environments in order to display the radio maps in a natural, easy-to-perceive manner. The results of this approach illustrate its added value to the field of radio resource planning of industrial communication systems. PMID:26167533

  7. Pervasive Radio Mapping of Industrial Environments Using a Virtual Reality Approach.

    PubMed

    Nedelcu, Adrian-Valentin; Machedon-Pisu, Mihai; Duguleana, Mihai; Talaba, Doru

    2015-01-01

    Wireless communications in industrial environments are seriously affected by reliability and performance issues, due to the multipath nature of obstacles within such environments. Special attention needs to be given to planning a wireless industrial network, so as to find the optimum spatial position for each of the nodes within the network, and especially for key nodes such as gateways or cluster heads. The aim of this paper is to present a pervasive radio mapping system which captures (senses) data regarding the radio spectrum, using low-cost wireless sensor nodes. This data is the input of radio mapping algorithms that generate electromagnetic propagation profiles. Such profiles are used for identifying obstacles within the environment and optimum propagation pathways. With the purpose of further optimizing the radio planning process, the authors propose a novel human-network interaction (HNI) paradigm that uses 3D virtual environments in order to display the radio maps in a natural, easy-to-perceive manner. The results of this approach illustrate its added value to the field of radio resource planning of industrial communication systems.

  8. Inter-City Virtual Water Transfers Within a Large Metropolitan Area: A Case Study of the Phoenix Metropolitan Area in the United States

    NASA Astrophysics Data System (ADS)

    Rushforth, R.; Ruddell, B. L.

    2014-12-01

    Water footprints have been proposed as potential sustainability indicators, but these analyses have thus far focused at the country-level or regional scale. However, for many countries, especially the United States, the most relevant level of water decision-making is the city. For water footprinting to inform urban sustainability, the boundaries for analysis must match the relevant boundaries for decision-making and economic development. Initial studies into city-level water footprints have provided insight into how large cities across the globe—Delhi, Lagos, Berlin, Beijing, York—create virtual water trade linkages with distant hinterlands. This study hypothesizes that for large cities the most direct and manageable virtual water flows exist at the metropolitan area scale and thus should provide the most policy-relevant information. This study represents an initial attempt at quantifying intra-metropolitan area virtual water flows. A modified commodity-by-industry input-output model was used to determine virtual water flows destined to, occurring within, and emanating from the Phoenix metropolitan area (PMA). Virtual water flows to and from the PMA were calculated for each PMA city using water consumption data as well as economic and industry statistics. Intra-PMA virtual water trade was determined using county-level traffic flow data, water consumption data, and economic and industry statistics. The findings show that there are archetypal cities within metropolitan areas and that each type of city has a distinct water footprint profile that is related to the value added economic processes occuring within their boundaries. These findings can be used to inform local water managers about the resilience of outsourced water supplies.

  9. Detecting navigational deficits in cognitive aging and Alzheimer disease using virtual reality.

    PubMed

    Cushman, Laura A; Stein, Karen; Duffy, Charles J

    2008-09-16

    Older adults get lost, in many cases because of recognized or incipient Alzheimer disease (AD). In either case, getting lost can be a threat to individual and public safety, as well as to personal autonomy and quality of life. Here we compare our previously described real-world navigation test with a virtual reality (VR) version simulating the same navigational environment. Quantifying real-world navigational performance is difficult and time-consuming. VR testing is a promising alternative, but it has not been compared with closely corresponding real-world testing in aging and AD. We have studied navigation using both real-world and virtual environments in the same subjects: young normal controls (YNCs, n = 35), older normal controls (ONCs, n = 26), patients with mild cognitive impairment (MCI, n = 12), and patients with early AD (EAD, n = 14). We found close correlations between real-world and virtual navigational deficits that increased across groups from YNC to ONC, to MCI, and to EAD. Analyses of subtest performance showed similar profiles of impairment in real-world and virtual testing in all four subject groups. The ONC, MCI, and EAD subjects all showed greatest difficulty in self-orientation and scene localization tests. MCI and EAD patients also showed impaired verbal recall about both test environments. Virtual environment testing provides a valid assessment of navigational skills. Aging and Alzheimer disease (AD) share the same patterns of difficulty in associating visual scenes and locations, which is complicated in AD by the accompanying loss of verbally mediated navigational capacities. We conclude that virtual navigation testing reveals deficits in aging and AD that are associated with potentially grave risks to our patients and the community.

  10. Rethinking the longitudinal stream temperature paradigm: region-wide comparison of thermal infrared imagery reveals unexpected complexity of river temperatures

    EPA Science Inventory

    We used an extensive dataset of remotely sensed summertime river temperature to compare longitudinal profiles (temperature versus distance) for 54 rivers in the Pacific Northwest. We evaluated (1) how often profiles fit theoretical expectations of asymptotic downstream warming, a...

  11. Bonding core mating surfaces improves transformer

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1978-01-01

    Modifications to assembly procedures for C-core transformers virtually eliminates changes in core end gaps due to temperature cycling during impregnation and potting stages, thus stabilizing magnetization properties of core.

  12. Distribution of sulphuric acid aerosols in the clouds and upper haze of Venus using Venus Express VAST and VeRa temperature profiles

    NASA Astrophysics Data System (ADS)

    Parkinson, Christopher D.; Gao, Peter; Schulte, Rick; Bougher, Stephen W.; Yung, Yuk L.; Bardeen, Charles G.; Wilquet, Valérie; Vandaele, Ann Carine; Mahieux, Arnaud; Tellmann, Silvia; Pätzold, Martin

    2015-08-01

    Observations from Pioneer Venus and from SPICAV/SOIR aboard Venus Express (VEx) have shown the upper haze (UH) of Venus to be highly spatially and temporally variable, and populated by multiple particle size modes. Previous models of this system (e.g., Gao et al., 2014. Icarus 231, 83-98), using a typical temperature profile representative of the atmosphere (viz., equatorial VIRA profile), did not investigate the effect of temperature on the UH particle distributions. We show that the inclusion of latitude-dependent temperature profiles for both the morning and evening terminators of Venus helps to explain how the atmospheric aerosol distributions vary spatially. In this work we use temperature profiles obtained by two instruments onboard VEx, VeRa and SPICAV/SOIR, to represent the latitudinal temperature dependence. We find that there are no significant differences between results for the morning and evening terminators at any latitude and that the cloud base moves downwards as the latitude increases due to decreasing temperatures. The UH is not affected much by varying the temperature profiles; however, the haze does show some periodic differences, and is slightly thicker at the poles than at the equator. We also find that the sulphuric acid "rain" seen in previous models may be restricted to the equatorial regions of Venus, such that the particle size distribution is relatively stable at higher latitudes and at the poles.

  13. Effect of thermal profile on cyclic flaw growth in aluminum

    NASA Technical Reports Server (NTRS)

    Engstrom, W. L.

    1975-01-01

    Surface flawed and single edge notch tension specimens of 2219-T851 and -T87 aluminum were tested to determine static fracture characteristics and base line (constant amplitude, constant temperature) cyclic flaw growth behavior. Subsequent testing was then conducted in which flawed specimens were subjected to a thermal profile in which the applied stress was varied simultaneously with the temperature. The profile used represents a simplified space shuttle orbiter load/temperature flight cycle. Test temperatures included the range from 144K (-200 F) up to 450K (350 F). The measured flaw growth rates obtained from the thermal profile tests were then compared with rates predicted by assuming linear cumulative damage of base line rates.

  14. Deviant bodies, stigmatized identities, and racist acts: examining the experiences of African-American gamers in Xbox Live

    NASA Astrophysics Data System (ADS)

    Gray, K. L.

    2012-12-01

    The purpose of this article is to illustrate how minority gamers, particularly African-American males, are subject to the label of deviant within the virtual gaming community of Xbox Live. They are labeled deviant based on the stigma of their physical identity - blackness, through a process of linguistic profiling. By employing virtual ethnography, the author identifies a process that leads to racism based on how the black gamer sounds within the space. The act of racism emerges through a process involving questioning, provoking, instigating, and ultimately racism. Many black gamers have normalized these racist experiences and have accepted the label of deviant placed upon their bodies.

  15. Dopant profile modeling by rare event enhanced domain-following molecular dynamics

    DOEpatents

    Beardmore, Keith M.; Jensen, Niels G.

    2002-01-01

    A computer-implemented molecular dynamics-based process simulates a distribution of ions implanted in a semiconductor substrate. The properties of the semiconductor substrate and ion dose to be simulated are first initialized, including an initial set of splitting depths that contain an equal number of virtual ions implanted in each substrate volume determined by the splitting depths. A first ion with selected velocity is input onto an impact position of the substrate that defines a first domain for the first ion during a first timestep, where the first domain includes only those atoms of the substrate that exert a force on the ion. A first position and velocity of the first ion is determined after the first timestep and a second domain of the first ion is formed at the first position. The first ion is split into first and second virtual ions if the first ion has passed through a splitting interval. The process then follows each virtual ion until all of the virtual ions have come to rest. A new ion is input to the surface and the process repeats until all of the ion dose has been input. The resulting ion rest positions form the simulated implant distribution.

  16. Twilight and nighttime ionospheric temperatures from oxygen 6300- and 5577-A spectral-line profiles.

    NASA Technical Reports Server (NTRS)

    Feibelman, W. A.; Hake, R. D., Jr.; Sipler, D. P.; Biondi , M. A.

    1972-01-01

    Use of Fabry-Perot interferometer measurements of atomic-oxygen 6300- and 5577-A line profiles from twilight and nightglow to determine the neutral temperatures in the F2 and E regions of the earth's ionosphere. The exospheric temperatures determined from the 6300-A profiles are usually somewhat higher than the temperatures calculated from Jacchia's model, and differences as large as about 300 K are noted when the exospheric temperature equals 1500 to 1600 K. The postsunset and predawn rate of change of the exospheric temperature is often substantially larger than the Jacchia prediction. The 5577-A (E region) measured temperatures range from 200 to 220 K on quiet nights to 500 to 600 K during geomagnetic storms.

  17. Temperature-profile methods for estimating percolation rates in arid environments

    USGS Publications Warehouse

    Constantz, Jim; Tyler, Scott W.; Kwicklis, Edward

    2003-01-01

    Percolation rates are estimated using vertical temperature profiles from sequentially deeper vadose environments, progressing from sediments beneath stream channels, to expansive basin-fill materials, and finally to deep fractured bedrock underlying mountainous terrain. Beneath stream channels, vertical temperature profiles vary over time in response to downward heat transport, which is generally controlled by conductive heat transport during dry periods, or by advective transport during channel infiltration. During periods of stream-channel infiltration, two relatively simple approaches are possible: a heat-pulse technique, or a heat and liquid-water transport simulation code. Focused percolation rates beneath stream channels are examined for perennial, seasonal, and ephemeral channels in central New Mexico, with estimated percolation rates ranging from 100 to 2100 mm d−1 Deep within basin-fill and underlying mountainous terrain, vertical temperature gradients are dominated by the local geothermal gradient, which creates a profile with decreasing temperatures toward the surface. If simplifying assumptions are employed regarding stratigraphy and vapor fluxes, an analytical solution to the heat transport problem can be used to generate temperature profiles at specified percolation rates for comparison to the observed geothermal gradient. Comparisons to an observed temperature profile in the basin-fill sediments beneath Frenchman Flat, Nevada, yielded water fluxes near zero, with absolute values <10 mm yr−1 For the deep vadose environment beneath Yucca Mountain, Nevada, the complexities of stratigraphy and vapor movement are incorporated into a more elaborate heat and water transport model to compare simulated and observed temperature profiles for a pair of deep boreholes. Best matches resulted in a percolation rate near zero for one borehole and 11 mm yr−1 for the second borehole.

  18. Climate reconstruction from borehole temperatures influenced by groundwater flow

    NASA Astrophysics Data System (ADS)

    Kurylyk, B.; Irvine, D. J.; Tang, W.; Carey, S. K.; Ferguson, G. A. G.; Beltrami, H.; Bense, V.; McKenzie, J. M.; Taniguchi, M.

    2017-12-01

    Borehole climatology offers advantages over other climate reconstruction methods because further calibration steps are not required and heat is a ubiquitous subsurface property that can be measured from terrestrial boreholes. The basic theory underlying borehole climatology is that past surface air temperature signals are reflected in the ground surface temperature history and archived in subsurface temperature-depth profiles. High frequency surface temperature signals are attenuated in the shallow subsurface, whereas low frequency signals can be propagated to great depths. A limitation of analytical techniques to reconstruct climate signals from temperature profiles is that they generally require that heat flow be limited to conduction. Advection due to groundwater flow can thermally `contaminate' boreholes and result in temperature profiles being rejected for regional climate reconstructions. Although groundwater flow and climate change can result in contrasting or superimposed thermal disturbances, groundwater flow will not typically remove climate change signals in a subsurface thermal profile. Thus, climate reconstruction is still possible in the presence of groundwater flow if heat advection is accommodated in the conceptual and mathematical models. In this study, we derive a new analytical solution for reconstructing surface temperature history from borehole thermal profiles influenced by vertical groundwater flow. The boundary condition for the solution is composed of any number of sequential `ramps', i.e. periods with linear warming or cooling rates, during the instrumented and pre-observational periods. The boundary condition generation and analytical temperature modeling is conducted in a simple computer program. The method is applied to reconstruct climate in Winnipeg, Canada and Tokyo, Japan using temperature profiles recorded in hydrogeologically active environments. The results demonstrate that thermal disturbances due to groundwater flow and climate change must be considered in a holistic manner as opposed to isolating either perturbation as was done in prior analytical studies.

  19. Bioturbo similarity searching: combining chemical and biological similarity to discover structurally diverse bioactive molecules.

    PubMed

    Wassermann, Anne Mai; Lounkine, Eugen; Glick, Meir

    2013-03-25

    Virtual screening using bioactivity profiles has become an integral part of currently applied hit finding methods in pharmaceutical industry. However, a significant drawback of this approach is that it is only applicable to compounds that have been biologically tested in the past and have sufficient activity annotations for meaningful profile comparisons. Although bioactivity data generated in pharmaceutical institutions are growing on an unprecedented scale, the number of biologically annotated compounds still covers only a minuscule fraction of chemical space. For a newly synthesized compound or an isolated natural product to be biologically characterized across multiple assays, it may take a considerable amount of time. Consequently, this chemical matter will not be included in virtual screening campaigns based on bioactivity profiles. To overcome this problem, we herein introduce bioturbo similarity searching that uses chemical similarity to map molecules without biological annotations into bioactivity space and then searches for biologically similar compounds in this reference system. In benchmark calculations on primary screening data, we demonstrate that our approach generally achieves higher hit rates and identifies structurally more diverse compounds than approaches using chemical information only. Furthermore, our method is able to discover hits with novel modes of inhibition that traditional 2D and 3D similarity approaches are unlikely to discover. Test calculations on a set of natural products reveal the practical utility of the approach for identifying novel and synthetically more accessible chemical matter.

  20. Study on the Characteristics of Plasma Profiles in Improved Confinement Plasmas in HT-7 Superconducting Tokamak

    NASA Astrophysics Data System (ADS)

    Zhang, Shouyin; Gao, Xiang; Li, Jiangang; Wan, Baonian; Kuang, Guangli; Mao, Jianshan; Zhang, Xiaodong; Xie, Jikang; Wan, Yuanxi; Team HT-7

    2000-10-01

    In HT-7 superconducting tokamak of circular limiter configuration (R0=122cm, a=30cm, Bt:1 ~2.2T), plasma profiles were modified and controlled by means of gas puffing, supersonic molecule injection, pellet injection, ICRF and IBW heating as well as LHW heating and current drive; improved plasma confinements were achieved either by application of one of the above measures or by the combination of them, study of the effects of the characteristics of plasma profiles on plasma confinements were performed. The results show that in most of the improved confinement plasmas in HT-7, there are very steep and strong peeking electron temperature profiles in core plasma, and/or large decrease of local temperature in radius of 0.5 ~0.7a which makes temperature gradient steeper when improvements begin, as temperature profile evolves back to previous normal shape the improvements end. Electron density profile and soft X-ray profiles were studied as well. This research was supported under Natural Science Foundation of China contract No.19905010.

  1. Improving Forecast Skill by Assimilation of AIRS Temperature Soundings

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Reale, Oreste

    2010-01-01

    AIRS was launched on EOS Aqua on May 4, 2002, together with AMSU-A and HSB, to form a next generation polar orbiting infrared and microwave atmospheric sounding system. The primary products of AIRS/AMSU-A are twice daily global fields of atmospheric temperature-humidity profiles, ozone profiles, sea/land surface skin temperature, and cloud related parameters including OLR. The AIRS Version 5 retrieval algorithm, is now being used operationally at the Goddard DISC in the routine generation of geophysical parameters derived from AIRS/AMSU data. A major innovation in Version 5 is the ability to generate case-by-case level-by-level error estimates delta T(p) for retrieved quantities and the use of these error estimates for Quality Control. We conducted a number of data assimilation experiments using the NASA GEOS-5 Data Assimilation System as a step toward finding an optimum balance of spatial coverage and sounding accuracy with regard to improving forecast skill. The model was run at a horizontal resolution of 0.5 deg. latitude X 0.67 deg longitude with 72 vertical levels. These experiments were run during four different seasons, each using a different year. The AIRS temperature profiles were presented to the GEOS-5 analysis as rawinsonde profiles, and the profile error estimates delta (p) were used as the uncertainty for each measurement in the data assimilation process. We compared forecasts analyses generated from the analyses done by assimilation of AIRS temperature profiles with three different sets of thresholds; Standard, Medium, and Tight. Assimilation of Quality Controlled AIRS temperature profiles significantly improve 5-7 day forecast skill compared to that obtained without the benefit of AIRS data in all of the cases studied. In addition, assimilation of Quality Controlled AIRS temperature soundings performs better than assimilation of AIRS observed radiances. Based on the experiments shown, Tight Quality Control of AIRS temperature profile performs best on the average from the perspective of improving Global 7 day forecast skill.

  2. The temperature profile in a forest

    Treesearch

    H.A. Fowells

    1948-01-01

    The temperature profile of a mature forest seldom has been observed. Temperatures at specific locations are of interest to the forester because they may help explain many phenomena, such as growth or death of seedlings and freezing of terminals and floral parts of trees. The opportunity to combine a vertical succession of such temperature measurements into a...

  3. Thermal Profiles for Selected River Reaches in the Yakima River Basin, Washington

    USGS Publications Warehouse

    Vaccaro, J.J.; Keys, M.E.; Julich, R.J.; Welch, W.B.

    2008-01-01

    Thermal profiles (data sets of longitudinal near-streambed temperature) that provide information on areas of potential ground-water discharge and salmonid habitat for 11 river reaches in the Yakima River basin, Washington, are available as Microsoft Excel? files that can be downloaded from the Internet. Two reaches were profiled twice resulting in 13 profiles. Data were collected for all but one thermal profile during 2001. Data consist of date and time (Pacific Daylight), near-streambed water temperature, and latitude and longitude collected concurrently using a temperature probe and a Global Positioning System. The data were collected from a watercraft towing the probe with an internal datalogger while moving downstream in a Lagrangian framework.

  4. Detecting navigational deficits in cognitive aging and Alzheimer disease using virtual reality

    PubMed Central

    Cushman, Laura A.; Stein, Karen; Duffy, Charles J.

    2008-01-01

    Background: Older adults get lost, in many cases because of recognized or incipient Alzheimer disease (AD). In either case, getting lost can be a threat to individual and public safety, as well as to personal autonomy and quality of life. Here we compare our previously described real-world navigation test with a virtual reality (VR) version simulating the same navigational environment. Methods: Quantifying real-world navigational performance is difficult and time-consuming. VR testing is a promising alternative, but it has not been compared with closely corresponding real-world testing in aging and AD. We have studied navigation using both real-world and virtual environments in the same subjects: young normal controls (YNCs, n = 35), older normal controls (ONCs, n = 26), patients with mild cognitive impairment (MCI, n = 12), and patients with early AD (EAD, n = 14). Results: We found close correlations between real-world and virtual navigational deficits that increased across groups from YNC to ONC, to MCI, and to EAD. Analyses of subtest performance showed similar profiles of impairment in real-world and virtual testing in all four subject groups. The ONC, MCI, and EAD subjects all showed greatest difficulty in self-orientation and scene localization tests. MCI and EAD patients also showed impaired verbal recall about both test environments. Conclusions: Virtual environment testing provides a valid assessment of navigational skills. Aging and Alzheimer disease (AD) share the same patterns of difficulty in associating visual scenes and locations, which is complicated in AD by the accompanying loss of verbally mediated navigational capacities. We conclude that virtual navigation testing reveals deficits in aging and AD that are associated with potentially grave risks to our patients and the community. GLOSSARY AD = Alzheimer disease; EAD = early Alzheimer disease; MCI = mild cognitive impairment; MMSE = Mini-Mental State Examination; ONC = older normal control; std. wt. = standardized weight; THSD = Tukey honestly significant difference; VR = virtual reality; YNC = young normal control. PMID:18794491

  5. Virtual anthropology: useful radiological tools for age assessment in clinical forensic medicine and thanatology.

    PubMed

    Dedouit, Fabrice; Saint-Martin, Pauline; Mokrane, Fatima-Zohra; Savall, Frédéric; Rousseau, Hervé; Crubézy, Eric; Rougé, Daniel; Telmon, Norbert

    2015-09-01

    Virtual anthropology consists of the introduction of modern slice imaging to biological and forensic anthropology. Thanks to this non-invasive scientific revolution, some classifications and staging systems, first based on dry bone analysis, can be applied to cadavers with no need for specific preparation, as well as to living persons. Estimation of bone and dental age is one of the possibilities offered by radiology. Biological age can be estimated in clinical forensic medicine as well as in living persons. Virtual anthropology may also help the forensic pathologist to estimate a deceased person's age at death, which together with sex, geographical origin and stature, is one of the important features determining a biological profile used in reconstructive identification. For this forensic purpose, the radiological tools used are multislice computed tomography and, more recently, X-ray free imaging techniques such as magnetic resonance imaging and ultrasound investigations. We present and discuss the value of these investigations for age estimation in anthropology.

  6. Acoustic propagation in a thermally stratified atmosphere

    NASA Technical Reports Server (NTRS)

    Vanmoorhem, W. K.

    1988-01-01

    Acoustic propagation in an atmosphere with a specific form of a temperature profile has been investigated by analytical means. The temperature profile used is representative of an actual atmospheric profile and contains three free parameters. Both lapse and inversion cases have been considered. Although ray solutions have been considered, the primary emphasis has been on solutions of the acoustic wave equation with point source where the sound speed varies with height above the ground corresponding to the assumed temperature profile. The method used to obtain the solution of the wave equation is based on Hankel transformation of the wave equation, approximate solution of the transformed equation for wavelength small compared to the scale of the temperature (or sound speed) profile, and approximate or numerical inversion of the Hankel transformed solution. The solution displays the characteristics found in experimental data but extensive comparison between the models and experimental data has not been carried out.

  7. Are anharmonicity corrections needed for temperature-profile calculations of interiors of terrestrial planets

    NASA Astrophysics Data System (ADS)

    Anderson, O. L.

    1982-07-01

    The temperature profile of planetary interiors is an important item of information, because many thermodynamic or geodynamic investigations of a planet's interior require an estimate of the temperature profile. Modeling studies of the thermal history or convective processes focus in detail on the thermal profile of the planet. A description is presented of results which show how the present (or equilibrium) interior temperature profile is related to certain constraints placed on the planet, especially the physical properties of the mantle material. These properties depend upon a priori assumptions of chemical composition. The investigation is mainly concerned with experimental and theoretical data appropriate to mantle minerals, in order to justify the use of a simple equation-of-state for planet interiors. It is found that anharmonicity does not seem to be required for calculations of interior properties of the terrestrial planets.

  8. Acoustic propagation in a thermally stratified atmosphere

    NASA Technical Reports Server (NTRS)

    Vanmoorhem, W. K.

    1987-01-01

    Acoustic propagation in an atmosphere with a specific form of temperature profile has been investigated by analytical means. The temperature profile used is representative of an actual atmospheric profile and contains three free parameters. Both lapse and inversion cases have been considered. Although ray solution have been considered the primary emphasis has been on solutions of the acoustic wave equation with point force where the sound speed varies with height above the ground corresponding to the assumed temperature profile. The method used to obtain the solution of the wave equation is based on Hankel transformation of the wave equation, approximate solution of the transformed equation for wavelength small compared to the scale of the temperature (or sound speed) profile, and approximate or numerical inversion of the Hankel transformed solution. The solution displays the characteristics found in experimental data but extensive comparison between the models and experimental data has not been carried out.

  9. Maine Geological Survey Borehole Temperature Profiles

    DOE Data Explorer

    Marvinney, Robert

    2013-11-06

    This dataset includes temperature profiles from 30 boreholes throughout Maine that were selected for their depth, location, and lithologies encountered. Depths range from about 300 feet to 2,200 feet. Most of the boreholes selected for measurement were completed in granite because this lithology can be assumed to be nearly homogeneous over the depth of the borehole. Boreholes were also selected to address gaps in existing geothermal datasets. Temperature profiles were collected in October and November, 2012.

  10. Using virtual reality to characterize episodic memory profiles in amnestic mild cognitive impairment and Alzheimer's disease: influence of active and passive encoding.

    PubMed

    Plancher, G; Tirard, A; Gyselinck, V; Nicolas, S; Piolino, P

    2012-04-01

    Most neuropsychological assessments of episodic memory bear little similarity to the events that patients actually experience as memories in daily life. The first aim of this study was to use a virtual environment to characterize episodic memory profiles in an ecological fashion, which includes memory for central and perceptual details, spatiotemporal contextual elements, and binding. This study included subjects from three different populations: healthy older adults, patients with amnestic mild cognitive impairment (aMCI) and patients with early to moderate Alzheimer's disease (AD). Second, we sought to determine whether environmental factors that can affect encoding (active vs. passive exploration) influence memory performance in pathological aging. Third, we benchmarked the results of our virtual reality episodic memory test against a classical memory test and a subjective daily memory complaint scale. Here, the participants were successively immersed in two virtual environments; the first, as the driver of a virtual car (active exploration) and the second, as the passenger of that car (passive exploration). Subjects were instructed to encode all elements of the environment as well as the associated spatiotemporal contexts. Following each immersion, we assessed the patient's recall and recognition of central information (i.e., the elements of the environment), contextual information (i.e., temporal, egocentric and allocentric spatial information) and lastly, the quality of binding. We found that the AD patients' performances were inferior to that of the aMCI and even more to that of the healthy aged groups, in line with the progression of hippocampal atrophy reported in the literature. Spatial allocentric memory assessments were found to be particularly useful for distinguishing aMCI patients from healthy older adults. Active exploration yielded enhanced recall of central and allocentric spatial information, as well as binding in all groups. This led aMCI patients to achieve better performance scores on immediate temporal memory tasks. Finally, the patients' daily memory complaints were more highly correlated with the performances on the virtual test than with their performances on the classical memory test. Taken together, these results highlight specific cognitive differences found between these three populations that may provide additional insight into the early diagnosis and rehabilitation of pathological aging. In particular, neuropsychological studies would benefit to use virtual tests and a multi-component approach to assess episodic memory, and encourage active encoding of information in patients suffering from mild or severe age-related memory impairment. The beneficial effect of active encoding on episodic memory in aMCI and early to moderate AD is discussed in the context of relatively preserved frontal and motor brain functions implicated in self-referential effects and procedural abilities. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Developing a Virtual Rock Deformation Laboratory

    NASA Astrophysics Data System (ADS)

    Zhu, W.; Ougier-simonin, A.; Lisabeth, H. P.; Banker, J. S.

    2012-12-01

    Experimental rock physics plays an important role in advancing earthquake research. Despite its importance in geophysics, reservoir engineering, waste deposits and energy resources, most geology departments in U.S. universities don't have rock deformation facilities. A virtual deformation laboratory can serve as an efficient tool to help geology students naturally and internationally learn about rock deformation. Working with computer science engineers, we built a virtual deformation laboratory that aims at fostering user interaction to facilitate classroom and outreach teaching and learning. The virtual lab is built to center around a triaxial deformation apparatus in which laboratory measurements of mechanical and transport properties such as stress, axial and radial strains, acoustic emission activities, wave velocities, and permeability are demonstrated. A student user can create her avatar to enter the virtual lab. In the virtual lab, the avatar can browse and choose among various rock samples, determine the testing conditions (pressure, temperature, strain rate, loading paths), then operate the virtual deformation machine to observe how deformation changes physical properties of rocks. Actual experimental results on the mechanical, frictional, sonic, acoustic and transport properties of different rocks at different conditions are compiled. The data acquisition system in the virtual lab is linked to the complied experimental data. Structural and microstructural images of deformed rocks are up-loaded and linked to different deformation tests. The integration of the microstructural image and the deformation data allows the student to visualize how forces reshape the structure of the rock and change the physical properties. The virtual lab is built using the Game Engine. The geological background, outstanding questions related to the geological environment, and physical and mechanical concepts associated with the problem will be illustrated on the web portal. In addition, some web based data collection tools are available to collect student feedback and opinions on their learning experience. The virtual laboratory is designed to be an online education tool that facilitates interactive learning.; Virtual Deformation Laboratory

  12. Using Distributed Temperature Sensing for measuring vertical temperature profiles and air temperature variance in the roughness sublayer above a forest canopy

    NASA Astrophysics Data System (ADS)

    Schilperoort, B.; Coenders, M.; Savenije, H. H. G.

    2017-12-01

    In recent years, the accuracy and resolution of Distributed Temperature Sensing (DTS) machines has increased enough to expand its use in atmospheric sciences. With DTS the temperature of a fiber optic (FO) cable can be measured with a high frequency (1 Hz) and high resolution (0.30 m), for cable lengths up to kilometers. At our measurement site, a patch of 26 to 30 m tall Douglas Fir in mixed forest, we placed FO cables vertically along a 48 m tall flux tower. This gives a high resolution vertical temperature profile above, through, and below the canopy. By using a `bare' FO cable, with a diameter of 0.25 mm, we are able to measure variations in air temperature at a very small timescale, and are able to measure a vertical profile of the air temperature variance. The vertical temperature profiles can be used to study the formation of the stable boundary layer above and in the canopy at a high resolution. It also shows that a stable layer can develop below the canopy, which is not limited to night time conditions but also occurs during daytime. The high frequency measurements can be used to study the gradient of the variance of air temperature over the height. To study how the flux tower itself affects temperature variance measurements, the `bare' FO cable can be placed horizontally under a support structure away from the flux tower. Lastly, by using the hot-wire anemometer principle with DTS, the measurements can be expanded to also include vertical wind profile.

  13. Simulation Based Optimization of Complex Monolithic Composite Structures Using Cellular Core Technology

    NASA Astrophysics Data System (ADS)

    Hickmott, Curtis W.

    Cellular core tooling is a new technology which has the capability to manufacture complex integrated monolithic composite structures. This novel tooling method utilizes thermoplastic cellular cores as inner tooling. The semi-rigid nature of the cellular cores makes them convenient for lay-up, and under autoclave temperature and pressure they soften and expand providing uniform compaction on all surfaces including internal features such as ribs and spar tubes. This process has the capability of developing fully optimized aerospace structures by reducing or eliminating assembly using fasteners or bonded joints. The technology is studied in the context of evaluating its capabilities, advantages, and limitations in developing high quality structures. The complex nature of these parts has led to development of a model using the Finite Element Analysis (FEA) software Abaqus and the plug-in COMPRO Common Component Architecture (CCA) provided by Convergent Manufacturing Technologies. This model utilizes a "virtual autoclave" technique to simulate temperature profiles, resin flow paths, and ultimately deformation from residual stress. A model has been developed simulating the temperature profile during curing of composite parts made with the cellular core technology. While modeling of composites has been performed in the past, this project will look to take this existing knowledge and apply it to this new manufacturing method capable of building more complex parts and develop a model designed specifically for building large, complex components with a high degree of accuracy. The model development has been carried out in conjunction with experimental validation. A double box beam structure was chosen for analysis to determine the effects of the technology on internal ribs and joints. Double box beams were manufactured and sectioned into T-joints for characterization. Mechanical behavior of T-joints was performed using the T-joint pull-off test and compared to traditional tooling methods. Components made with the cellular core tooling method showed an improved strength at the joints. It is expected that this knowledge will help optimize the processing of complex, integrated structures and benefit applications in aerospace where lighter, structurally efficient components would be advantageous.

  14. Stream bed temperature profiles as indicators of percolation characteristics beneath arroyos in the middle Rio Grande Basin, USA

    USGS Publications Warehouse

    Constantz, J.; Thomas, C.L.

    1997-01-01

    Stream bed temperature profiles were monitored continuously during water year 1990 and 1991 (WY90 and 91) in two New Mexico arroyos, similar in their meteorological features and dissimilar in their hydrological features. Stream bed temperature profiles between depths of 30 and 300 cm were examined to determine whether temporal changes in temperature profiles represent accurate indicators of the timing, depth and duration of percolation in each stream bed. These results were compared with stream flow, air temperature, and precipitation records for WY90 and 91, to evaluate the effect of changing surface conditions on temperature profiles. Temperature profiles indicate a persistently high thermal gradient with depth beneath Grantline Arroyo, except during a semi-annual thermal reversal in spring and autumn. This typifies the thermal response of dry sediments with low thermal conductivities. High thermal gradients were disrupted only during infrequent stream flows, followed by rapid re-establishment of high gradients. The stream bed temperature at 300 cm was unresponsive to individual precipitation or stream flow during WY90 and 91. This thermal pattern provides strong evidence that most seepage into Grantline Arroyo failed to percolate at a sufficient rate to reach 300 cm before being returned to the atmosphere. A distinctly different thermal pattern was recorded beneath Tijeras Arroyo. Low thermal gradients between 30 and 300 cm and large diurnal variations in temperature, suggest that stream flow created continuous, advection-dominated heat transport for over 300 days, annually. Beneath Tijeras Arroyo, low thermal gradients were interrupted only briefly during periodic, dry summer conditions. Comparisons of stream flow records for WY90 and 91 with stream bed temperature profiles indicate that independent analysis of thermal patterns provides accurate estimates of the timing, depth and duration of percolation beneath both arroyos. Stream flow loss estimates indicate that seepage rates were 15 times greater for Tijeras Arroyo than for Grantline Arroyo, which supports qualitative conclusions derived from analysis of stream bed temperature responses to surface conditions. ?? 1997 John Wiley & Sons, Ltd.

  15. Analysis of the NASA AirMOSS Root Zone Soil Water and Soil Temperature from Three North American Ecosystems

    NASA Astrophysics Data System (ADS)

    Hagimoto, Y.; Cuenca, R. H.

    2015-12-01

    Root zone soil water and temperature are controlling factors for soil organic matter accumulation and decomposition which contribute significantly to the CO2 flux of different ecosystems. An in-situ soil observation protocol developed at Oregon State University has been deployed to observe soil water and temperature dynamics in seven ecological research sites in North America as part of the NASA AirMOSS project. Three instrumented profiles defining a transect of less than 200 m are installed at each site. All three profiles collect data for in-situ water and temperature dynamics employing seven soil water and temperature sensors installed at seven depth levels and one infrared surface temperature sensor monitoring the top of the profile. In addition, two soil heat flux plates and associated thermocouples are installed at one of three profiles at each site. At each profile, a small 80 cm deep access hole is typically made, and all below ground sensors are installed into undisturbed soil on the side of the hole. The hole is carefully refilled and compacted so that root zone soil water and temperature dynamics can be observed with minimum site disturbance. This study focuses on the data collected from three sites: a) Tonzi Ranch, CA; b) Metolius, OR and c) BERMS Old Jack Pine Site, Saskatchewan, Canada. The study describes the significantly different seasonal root zone water and temperature dynamics under the various physical and biological conditions at each site. In addition, this study compares the soil heat flux values estimated by the standard installation using the heat flux plates and thermocouples installed near the surface with those estimated by resolving the soil heat storage based on the soil water and temperature data collected over the total soil profile.

  16. Thermoregulatory and Orthostatic Responses to Wearing the Advanced Crew Escape Suit

    NASA Technical Reports Server (NTRS)

    Lee, Stuart M. C.; Jacobs, Tamara N.; McDaniel, Angela; Schneider, Suzanne M.

    2006-01-01

    Current NASA flight rules limit the maximum cabin temperature (23.9 C) during re-entry and landing to protect crewmembers from heat stress while wearing the Advanced Crew Escape Suit (ACES) and Liquid Cooling Garment (LCG). The primary purpose of this ground-based project was to determine whether the LCG could provide adequate cooling if ambient temperature reached 26.7 "C. The secondary objective was to determine whether there would be a graded effect of ambient temperature profiles with maximum temperatures of 23.9 (LO), 26.7 (MPD), and 29.4 C (HI). METHODS: Eight subjects underwent a 5-h temperature profile (22.8,26.7 C) in an environmental chamber while wearing the ACES and LCG. Subjects controlled the amount of cooling provided by the LCG. Core (T(sub core)),skin temperatures (T(sub sk)) and heart rate (HR) were measured every 15-min. A 10-minute stand test was administered pre- and post-chamber. Additionally, 4 subjects underwent the three 5-h temperature profiles (LO, MID, and HI) with the same measurements. RESULTS: In the 8 subjects completing the MID profile, T(sub core), and T(sub sk) decreased from the start' to the end of the chamber stay. Subjects completed the stand test without signs of orthostatic intolerance. In the 4 subjects who underwent all 3 profiles, there was no discernible pattern in T(sub core), T(sub sk), and HR responses across the temperature profiles. CONCLUSIONS: In the range of temperatures tested, subjects were able to sufficiently utilize the self-selected cooling to avoid any potential deleterious effects of wearing the ACES. However, these subjects were not microgravity exposed, which has been suggested to impair thermoregulation.

  17. Sub-millikelvin stabilization of a closed cycle cryocooler.

    PubMed

    Dubuis, Guy; He, Xi; Božović, Ivan

    2014-10-01

    Intrinsic temperature oscillations (with the amplitude up to 1 K) of a closed cycle cryocooler are stabilized by a simple thermal damping system. It employs three different materials with different thermal conductivity and specific heat at various temperatures. The amplitude of oscillations of the sample temperature is reduced to less than 1 mK, in the temperature range from 4 K to 300 K, while the cooling power is virtually undiminished. The damping system is small, inexpensive, can be retrofitted to most existing closed cycle cryocoolers, and may improve measurements of any temperature-sensitive physics properties.

  18. Sub-millikelvin stabilization of a closed cycle cryocooler

    DOE PAGES

    Dubuis, Guy; He, Xi; Božović, Ivan

    2014-10-03

    In this study, intrinsic temperature oscillations (with the amplitude up to 1 K) of a closed cycle cryocooler are stabilized by a simple thermal damping system. It employs three different materials with different thermal conductivity and capacity at various temperatures. The amplitude of oscillations of the sample temperature is reduced to less than 1 mK, in the temperature range from 4 K to 300 K, while the cooling power is virtually undiminished. The damping system is small, inexpensive, can be retrofitted to most existing closed cycle cryocoolers, and may improve measurements of any temperature-sensitive physics properties.

  19. Application of GPS radio occultation to the assessment of temperature profile retrievals from microwave and infrared sounders

    NASA Astrophysics Data System (ADS)

    Feltz, M.; Knuteson, R.; Ackerman, S.; Revercomb, H.

    2014-05-01

    Comparisons of satellite temperature profile products from GPS radio occultation (RO) and hyperspectral infrared (IR)/microwave (MW) sounders are made using a previously developed matchup technique. The profile matchup technique matches GPS RO and IR/MW sounder profiles temporally, within 1 h, and spatially, taking into account the unique RO profile geometry and theoretical spatial resolution by calculating a ray-path averaged sounder profile. The comparisons use the GPS RO dry temperature product. Sounder minus GPS RO differences are computed and used to calculate bias and RMS profile statistics, which are created for global and 30° latitude zones for selected time periods. These statistics are created from various combinations of temperature profile data from the Constellation Observing System for Meteorology, Ionosphere & Climate (COSMIC) network, Global Navigation Satellite System Receiver for Atmospheric Sounding (GRAS) instrument, and the Atmospheric Infrared Sounder (AIRS)/Advanced Microwave Sounding Unit (AMSU), Infrared Atmospheric Sounding Interferometer (IASI)/AMSU, and Crosstrack Infrared Sounder (CrIS)/Advanced Technology Microwave Sounder (ATMS) sounding systems. By overlaying combinations of these matchup statistics for similar time and space domains, comparisons of different sounders' products, sounder product versions, and GPS RO products can be made. The COSMIC GPS RO network has the spatial coverage, time continuity, and stability to provide a common reference for comparison of the sounder profile products. The results of this study demonstrate that GPS RO has potential to act as a common temperature reference and can help facilitate inter-comparison of sounding retrieval methods and also highlight differences among sensor product versions.

  20. Application of GPS radio occultation to the assessment of temperature profile retrievals from microwave and infrared sounders

    NASA Astrophysics Data System (ADS)

    Feltz, M.; Knuteson, R.; Ackerman, S.; Revercomb, H.

    2014-11-01

    Comparisons of satellite temperature profile products from GPS radio occultation (RO) and hyperspectral infrared (IR)/microwave (MW) sounders are made using a previously developed matchup technique. The profile matchup technique matches GPS RO and IR/MW sounder profiles temporally, within 1 h, and spatially, taking into account the unique RO profile geometry and theoretical spatial resolution by calculating a ray-path averaged sounder profile. The comparisons use the GPS RO dry temperature product. Sounder minus GPS RO differences are computed and used to calculate bias and rms profile statistics, which are created for global and 30° latitude zones for selected time periods. These statistics are created from various combinations of temperature profile data from the Constellation Observing System for Meteorology, Ionosphere & Climate (COSMIC) network, Global Navigation Satellite System Receiver for Atmospheric Sounding (GRAS) instrument, and the Atmospheric Infrared Sounder (AIRS)/Advanced Microwave Sounding Unit (AMSU), Infrared Atmospheric Sounding Interferometer (IASI)/AMSU, and Crosstrack Infrared Sounder (CrIS)/Advanced Technology Microwave Sounder (ATMS) sounding systems. By overlaying combinations of these matchup statistics for similar time and space domains, comparisons of different sounders' products, sounder product versions, and GPS RO products can be made. The COSMIC GPS RO network has the spatial coverage, time continuity, and stability to provide a common reference for comparison of the sounder profile products. The results of this study demonstrate that GPS RO has potential to act as a common temperature reference and can help facilitate inter-comparison of sounding retrieval methods and also highlight differences among sensor product versions.

  1. Comparison of potential temperature gradient estimates from various temperature profile data sources

    DOT National Transportation Integrated Search

    2017-01-22

    From July through September 2015, concurrent and collocated measurements of temperature profiles from two passive radiometers and a RADAR-RASS (Radio Acoustic Sounding System) were made at a site near the ocean just to the west of Los Angeles Interna...

  2. Automated system for measuring temperature profiles inside ITS-90 fixed-point cells

    NASA Astrophysics Data System (ADS)

    Hiti, Miha; Bojkovski, Jovan; Batagelj, Valentin; Drnovsek, Janko

    2005-11-01

    The defining fixed points of the International Temperature Scale of 1990 (ITS-90) are temperature reference points for temperature calibration. The measured temperature inside the fixed-point cell depends on thermometer immersion, since measurements are made below the surface of the fixed-point material and the additional effect of the hydrostatic pressure has to be taken into account. Also, the heat flux along the thermometer stem can affect the measured temperature. The paper presents a system that enables accurate and reproducible immersion profile measurements for evaluation of measurement sensitivity and adequacy of thermometer immersion. It makes immersion profile measurements possible, where a great number of repetitions and long measurement periods are required, and reduces the workload on the user for performing such measurements. The system is flexible and portable and was developed for application to existing equipment in the laboratory. Results of immersion profile measurements in a triple point of water fixed-point cell are presented.

  3. Fundamental solutions to the bioheat equation and their application to magnetic fluid hyperthermia.

    PubMed

    Giordano, Mauricio A; Gutierrez, Gustavo; Rinaldi, Carlos

    2010-01-01

    Methods of predicting temperature profiles during local hyperthermia treatment are very important to avoid damage to healthy tissue. With this aim, fundamental solutions of Pennes' bioheat equation are derived in rectangular, cylindrical, and spherical coordinates. The medium is idealised as isotropic with effective thermal properties. Temperature distributions due to space- and time-dependent heat sources are obtained by the solution method presented. Applications of the fundamental solutions are addressed with emphasis on a particular problem of Magnetic Fluid Hyperthermia (MFH) consisting of a thin shell of magnetic nanoparticles in the outer surface of a spherical solid tumour. It is observed from the solution of this particular problem that the temperature profiles are strongly dependent on the distribution of the magnetic nanoparticles within the tissue. An almost uniform temperature profile is obtained inside the tumour with little penetration of therapeutic temperatures to the outer region of healthy tissue. The fundamental solutions obtained can be used to develop boundary element methods to predict temperature profiles with more complicated geometries.

  4. Rotational temperatures of Venus upper atmosphere as measured by SOIR on board Venus Express

    NASA Astrophysics Data System (ADS)

    Mahieux, A.; Vandaele, A. C.; Robert, S.; Wilquet, V.; Drummond, R.; López Valverde, M. A.; López Puertas, M.; Funke, B.; Bertaux, J. L.

    2015-08-01

    SOIR is a powerful infrared spectrometer flying on board the Venus Express spacecraft since mid-2006. It sounds the Venus atmosphere above the cloud layer using the solar occultation technique. In the recorded spectra, absorption structures from many species are observed, among them carbon dioxide, the main constituent of the Venus atmosphere. Previously, temperature vertical profiles were derived from the carbon dioxide density retrieved from the SOIR spectra by assuming hydrostatic equilibrium. These profiles show a permanent cold layer at 125 km with temperatures of ~100 K, surrounded by two warmer layers at 90 and 140 km, reaching temperatures of ~200 K and 250-300 K, respectively. In this work, temperature profiles are derived from the SOIR spectra using another technique based on the ro-vibrational structure of carbon dioxide observed in the spectra. The error budget is extensively investigated. Temperature profiles obtained by both techniques are comparable within their respective uncertainties and they confirm the vertical structure previously determined from SOIR spectra.

  5. Real-time measurements of temperature, pressure and moisture profiles in High-Performance Concrete exposed to high temperatures during neutron radiography imaging

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

    Toropovs, N., E-mail: nikolajs.toropovs@rtu.lv; Riga Technical University, Institute of Materials and Structures, Riga; Lo Monte, F.

    2015-02-15

    High-Performance Concrete (HPC) is particularly prone to explosive spalling when exposed to high temperature. Although the exact causes that lead to spalling are still being debated, moisture transport during heating plays an important role in all proposed mechanisms. In this study, slabs made of high-performance, low water-to-binder ratio mortars with addition of superabsorbent polymers (SAP) and polypropylene fibers (PP) were heated from one side on a temperature-controlled plate up to 550 °C. A combination of measurements was performed simultaneously on the same sample: moisture profiles via neutron radiography, temperature profiles with embedded thermocouples and pore pressure evolution with embedded pressuremore » sensors. Spalling occurred in the sample with SAP, where sharp profiles of moisture and temperature were observed. No spalling occurred when PP-fibers were introduced in addition to SAP. The experimental procedure described here is essential for developing and verifying numerical models and studying measures against fire spalling risk in HPC.« less

  6. Temperature adaptation of active sodium-potassium transport and of passive permeability in erythrocytes of ground squirrels.

    NASA Technical Reports Server (NTRS)

    Kimzey, S. L.; Willis, J. S.

    1971-01-01

    Unidirectional active and passive fluxes of K-42 and Na-24 were measured in red blood cells of ground squirrels (hibernators) and guinea pigs (nonhibernators). As the temperature was lowered, ?active' (ouabain-sensitive) K influx and Na efflux were more considerably diminished in guinea pig cells than in those of ground squirrels. The fraction of total K influx which is ouabain-sensitive in red blood cells of ground squirrels was virtually constant at all temperatures, whereas it decreased abruptly in guinea pig cells as temperature was lowered.

  7. High resolution humidity, temperature and aerosol profiling with MeteoSwiss Raman lidar

    NASA Astrophysics Data System (ADS)

    Dinoev, Todor; Arshinov, Yuri; Bobrovnikov, Sergei; Serikov, Ilya; Calpini, Bertrand; van den Bergh, Hubert; Parlange, Marc B.; Simeonov, Valentin

    2010-05-01

    Meteorological services rely, in part, on numerical weather prediction (NWP). Twice a day radiosonde observations of water vapor provide the required data for assimilation but this time resolution is insufficient to resolve certain meteorological phenomena. High time resolution temperature profiles from microwave radiometers are available as well but have rather low vertical resolution. The Raman LIDARs are able to provide temperature and humidity profiles with high time and range resolution, suitable for NWP model assimilation and validation. They are as well indispensible tools for continuous aerosol profiling for high resolution atmospheric boundary layer studies. To improve the database available for direct meteorological applications the Swiss meteo-service (MeteoSwiss), the Swiss Federal Institute of Technology in Lausanne (EPFL) and the Swiss National Science Foundation (SNSF) initiated a project to design and build an automated Raman lidar for day and night vertical profiling of tropospheric water vapor with the possibility to further upgrade it with an aerosol and temperature channels. The project was initiated in 2004 and RALMO (Raman Lidar for meteorological observations) was inaugurated in August 2008 at MeteoSwiss aerological station at Payerne. RALMO is currently operational and continuously profiles water vapor mixing ratio, aerosol backscatter ratio and aerosol extinction. The instrument is a fully automated, self-contained, eye-safe Raman lidar operated at 355 nm. Narrow field-of-view multi-telescope receiver and narrow band detection allow day and night-time vertical profiling of the atmospheric humidity. The rotational-vibrational Raman lidar responses from water vapor and nitrogen are spectrally separated by a high-throughput fiber coupled diffraction grating polychromator. The elastic backscatter and pure-rotational Raman lidar responses (PRR) from oxygen and nitrogen are spectrally isolated by a double grating polychromator and are used to derive vertical profiles of aerosol backscatter ratio and aerosol extinction at 355 nm. Set of Stokes and anti-Stokes PRR lines are separated by the polychromator to derive temperature profiles. The humidity profiles have vertical resolution from 15 m (within the boundary layer) to 100-450 m (within the free troposphere), time resolution of 30 min and 5 km vertical range at daytime and 10 km at night-time. The aerosol backscatter ratio and extinction profiles have similar resolution with vertical range of approximately 10 km. The temperature profiles are derived from PRR lidar signals, simultaneously recorded in analog and photon counting mode, allowing vertical range of approximately 10 km. Vaisala RS-92 and Snow-White chilled mirror hygrometer radiosondes were used for calibration of the water vapor and temperature channels. Continuous temperature profiles were obtained and were coupled with the available water vapor mixing ratio profiles to obtain relative humidity time series. Lidar derived aerosol backscatter ratio profiles will be used for estimation of the boundary layer height and validation of NWP model results. Optical thickness time series are currently compared to independent measurements from a collocated sun photometer to assess the performance of the aerosol channel.

  8. Differential absorption lidar measurements of atmospheric temperature and pressure profiles

    NASA Technical Reports Server (NTRS)

    Korb, C. L.

    1981-01-01

    The theory and methodology of using differential absorption lidar techniques for the remote measurement of atmospheric pressure profiles, surface pressure, and temperature profiles from ground, air, and space-based platforms are presented. Pressure measurements are effected by means of high resolution measurement of absorption at the edges of the oxygen A band lines where absorption is pressure dependent due to collisional line broadening. Temperature is assessed using measurements of the absorption at the center of the oxygen A band line originating from a quantum state with high ground state energy. The population of the state is temperature dependent, allowing determination of the temperature through the Boltzmann term. The results of simulations of the techniques using Voigt profile and variational analysis are reported for ground-based, airborne, and Shuttle-based systems. Accuracies in the 0.5-1.0 K and 0.1-0.3% range are projected.

  9. Spatially-resolved study of the Meissner effect in superconductors using NV-centers-in-diamond optical magnetometry

    NASA Astrophysics Data System (ADS)

    Nusran, N. M.; Joshi, K. R.; Cho, K.; Tanatar, M. A.; Meier, W. R.; Bud’ko, S. L.; Canfield, P. C.; Liu, Y.; Lograsso, T. A.; Prozorov, R.

    2018-04-01

    Non-invasive magnetic field sensing using optically-detected magnetic resonance of nitrogen-vacancy centers in diamond was used to study spatial distribution of the magnetic induction upon penetration and expulsion of weak magnetic fields in several representative superconductors. Vector magnetic fields were measured on the surface of conventional, elemental Pb and Nb, and compound LuNi2B2C and unconventional iron-based superconductors Ba1‑x K x Fe2As2 (x = 0.34 optimal hole doping), Ba(Fe1‑x Co x )2As2 (x = 0.07 optimal electron doping), and stoichiometric CaKFe4As4, using variable-temperature confocal system with diffraction-limited spatial resolution. Magnetic induction profiles across the crystal edges were measured in zero-field-cooled and field-cooled conditions. While all superconductors show nearly perfect screening of magnetic fields applied after cooling to temperatures well below the superconducting transition, T c, a range of very different behaviors was observed for Meissner expulsion upon cooling in static magnetic field from above T c. Substantial conventional Meissner expulsion is found in LuNi2B2C, paramagnetic Meissner effect is found in Nb, and virtually no expulsion is observed in iron-based superconductors. In all cases, good correlation with macroscopic measurements of total magnetic moment is found.

  10. Spatially-resolved study of the Meissner effect in superconductors using NV-centers-in-diamond optical magnetometry

    DOE PAGES

    Nusran, N. M.; Joshi, K. R.; Cho, K.; ...

    2018-04-12

    Non-invasive magnetic field sensing using optically-detected magnetic resonance of nitrogen-vacancy centers in diamond was used to study spatial distribution of the magnetic induction upon penetration and expulsion of weak magnetic fields in several representative superconductors. Vector magnetic fields were measured on the surface of conventional, elemental Pb and Nb, and compound LuNi 2B 2C and unconventional iron-based superconductors Ba 1-xK xFe 2As 2 (x = 0.34 optimal hole doping), Ba(Fe 1-xCo x)2As2 (x = 0.07 optimal electron doping), and stoichiometric CaKFe 4As 4, using variable-temperature confocal system with diffraction-limited spatial resolution. Magnetic induction profiles across the crystal edges were measuredmore » in zero-field-cooled and field-cooled conditions. While all superconductors show nearly perfect screening of magnetic fields applied after cooling to temperatures well below the superconducting transition, T c, a range of very different behaviors was observed for Meissner expulsion upon cooling in static magnetic field from above T c. Substantial conventional Meissner expulsion is found in LuNi 2B 2C, paramagnetic Meissner effect is found in Nb, and virtually no expulsion is observed in iron-based superconductors. In all cases, good correlation with macroscopic measurements of total magnetic moment is found.« less

  11. Spatially-resolved study of the Meissner effect in superconductors using NV-centers-in-diamond optical magnetometry

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

    Nusran, N. M.; Joshi, K. R.; Cho, K.

    Non-invasive magnetic field sensing using optically-detected magnetic resonance of nitrogen-vacancy centers in diamond was used to study spatial distribution of the magnetic induction upon penetration and expulsion of weak magnetic fields in several representative superconductors. Vector magnetic fields were measured on the surface of conventional, elemental Pb and Nb, and compound LuNi 2B 2C and unconventional iron-based superconductors Ba 1-xK xFe 2As 2 (x = 0.34 optimal hole doping), Ba(Fe 1-xCo x)2As2 (x = 0.07 optimal electron doping), and stoichiometric CaKFe 4As 4, using variable-temperature confocal system with diffraction-limited spatial resolution. Magnetic induction profiles across the crystal edges were measuredmore » in zero-field-cooled and field-cooled conditions. While all superconductors show nearly perfect screening of magnetic fields applied after cooling to temperatures well below the superconducting transition, T c, a range of very different behaviors was observed for Meissner expulsion upon cooling in static magnetic field from above T c. Substantial conventional Meissner expulsion is found in LuNi 2B 2C, paramagnetic Meissner effect is found in Nb, and virtually no expulsion is observed in iron-based superconductors. In all cases, good correlation with macroscopic measurements of total magnetic moment is found.« less

  12. Temperature-profile detector

    DOEpatents

    Not Available

    1981-01-29

    Temperature profiles at elevated temperature conditions are monitored by use of an elongated device having two conductors spaced by the minimum distance required to normally maintain an open circuit between them. The melting point of one conductor is selected at the elevated temperature being detected, while the melting point of the other is higher. As the preselected temperature is reached, liquid metal will flow between the conductors creating short circuits which are detectable as to location.

  13. Temperature profile detector

    DOEpatents

    Tokarz, Richard D.

    1983-01-01

    Temperature profiles at elevated temperature conditions are monitored by use of an elongated device having two conductors spaced by the minimum distance required to normally maintain an open circuit between them. The melting point of one conductor is selected at the elevated temperature being detected, while the melting point of the other is higher. As the preselected temperature is reached, liquid metal will flow between the conductors, creating short circuits which are detectable as to location.

  14. Quantum-dot temperature profiles during laser irradiation for semiconductor-doped glasses

    NASA Astrophysics Data System (ADS)

    Nagpal, Swati

    2002-12-01

    Temperature profiles around laser irradiated CdX (X=S, Se, and Te) quantum dots in borosilicate glasses were theoretically modeled. Initially the quantum dots heat up rapidly, followed by a gradual increase of temperature. Also it is found that larger dots reach higher temperatures for the same pulse characteristics. After the pulse is turned off, the dots initially cool rapidly, followed by a gradual decrease in temperature.

  15. Computer Program for Calculation of a Gas Temperature Profile by Infrared Emission: Absorption Spectroscopy

    NASA Technical Reports Server (NTRS)

    Buchele, D. R.

    1977-01-01

    A computer program to calculate the temperature profile of a flame or hot gas was presented in detail. Emphasis was on profiles found in jet engine or rocket engine exhaust streams containing H2O or CO2 radiating gases. The temperature profile was assumed axisymmetric with an assumed functional form controlled by two variable parameters. The parameters were calculated using measurements of gas radiation at two wavelengths in the infrared. The program also gave some information on the pressure profile. A method of selection of wavelengths was given that is likely to lead to an accurate determination of the parameters. The program is written in FORTRAN IV language and runs in less than 60 seconds on a Univac 1100 computer.

  16. Innate Immune Response and Off-Target Mis-splicing Are Common Morpholino-Induced Side Effects in Xenopus.

    PubMed

    Gentsch, George E; Spruce, Thomas; Monteiro, Rita S; Owens, Nick D L; Martin, Stephen R; Smith, James C

    2018-03-12

    Antisense morpholino oligomers (MOs) have been indispensable tools for developmental biologists to transiently knock down (KD) genes rather than to knock them out (KO). Here we report on the implications of genetic KO versus MO-mediated KD of the mesoderm-specifying Brachyury paralogs in the frog Xenopus tropicalis. While both KO and KD embryos fail to activate the same core gene regulatory network, resulting in virtually identical morphological defects, embryos injected with control or target MOs also show a systemic GC content-dependent immune response and many off-target splicing defects. Optimization of MO dosage and increasing incubation temperatures can mitigate, but not eliminate, these MO side effects, which are consistent with the high affinity measured between MO and off-target sequence in vitro. We conclude that while MOs can be useful to profile loss-of-function phenotypes at a molecular level, careful attention must be paid to their immunogenic and off-target side effects. Copyright © 2018 The Francis Crick Institute. Published by Elsevier Inc. All rights reserved.

  17. Ultrasonic phased array controller for hyperthermia applications.

    PubMed

    Benkeser, P J; Pao, T L; Yoon, Y J

    1991-01-01

    Multiple and mechanically scanned ultrasound transducer systems have demonstrated the efficacy of using ultrasound to produce deep localized hyperthermia. The use of ultrasonic phased arrays has been proposed as an alternative to these systems. A phased array offers a more flexible approach to heating tumours in that the size, shape, and position of its focal region can be altered during the course of treatment in order to achieve the desired temperature distribution. This added flexibility comes at the cost of increased complexity of the hardware necessary to drive the transducer because each element requires its own amplifer with both phase and amplitude control. In order for phased arrays with large numbers of elements to be feasible for hyperthermia applications, the complexity of this circuitry must be minimized. This paper describes a circuit design which simplifies the electronics required to control a phased array transducer system for hyperthermia applications. The design is capable of controlling virtually any type of phased array transducer operating at frequencies less than 2 MHz. The system performance was verified through beam profile measurements using a 48-element tapered phased array transducer.

  18. Reactor for producing large particles of materials from gases

    NASA Technical Reports Server (NTRS)

    Flagan, Richard C. (Inventor); Alam, Mohammed K. (Inventor)

    1987-01-01

    A method and apparatus is disclosed for producing large particles of material from gas, or gases, containing the material (e.g., silicon from silane) in a free-space reactor comprised of a tube (20) and controlled furnace (25). A hot gas is introduced in the center of the reactant gas through a nozzle (23) to heat a quantity of the reactant gas, or gases, to produce a controlled concentration of seed particles (24) which are entrained in the flow of reactant gas, or gases. The temperature profile (FIG. 4) of the furnace is controlled for such a slow, controlled rate of reaction that virtually all of the material released condenses on seed particles and new particles are not nucleated in the furnace. A separate reactor comprised of a tube (33) and furnace (30) may be used to form a seed aerosol which, after passing through a cooling section (34) is introduced in the main reactor tube (34) which includes a mixer (36) to mix the seed aerosol in a controlled concentration with the reactant gas or gases.

  19. HCMM energy budget data as a model input for assessing regions of high potential groundwater pollution

    NASA Technical Reports Server (NTRS)

    Moore, D. G. (Principal Investigator); Heilman, J.; Tunheim, J. A.; Baumberger, V.

    1978-01-01

    The author has identified the following significant results. To investigate the general relationship between surface temperature and soil moisture profiles, a series of model calculations were carried out. Soil temperature profiles were calculated during a complete diurnal cycle for a variety of moisture profiles. Preliminary results indicate the surface temperature difference between two sites measured at about 1400 hours is related to the difference in soil moisture within the diurnal damping depth (about 50 cm). The model shows this temperature difference to vary considerably throughout the diurnal cycle.

  20. Advances in atmospheric temperature profile measurements using high spectral resolution lidar

    NASA Astrophysics Data System (ADS)

    Razenkov, Ilya I.; Eloranta, Edwin W.

    2018-04-01

    This paper reports the atmospheric temperature profile measurements using a University of Wisconsin-Madison High Spectral Resolution Lidar (HSRL) and describes improvements in the instrument performance. HSRL discriminates between Mie and Rayleigh backscattering [1]. Thermal motion of molecules broadens the spectrum of the transmitted laser light due to Doppler effect. The HSRL exploits this property to allow the absolute calibration of the lidar and measurements of the aerosol volume backscatter coefficient. Two iodine absorption filters with different line widths are used to resolve temperature sensitive changes in Rayleigh backscattering for atmospheric temperature profile measurements.

  1. Elastic positron scattering by C{sub 2}H{sub 2}: Differential cross sections and virtual state formation

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

    Carvalho, Claudia R.C. de; Varella, Marcio T. do N; Lima, Marco A.P.

    2003-12-01

    We present calculated elastic differential cross sections for positron-acetylene scattering, obtained by using the Schwinger multichannel method. Our results are in very good agreement with quasielastic experimental data of Kauppila et al. [Nucl. Instrum. Meth. Phys. Res. B 192, 162 (2002)]. We also discuss the existence of a virtual state (zero-energy resonance) in e{sup +}-C{sub 2}H{sub 2} collisions, based on the behavior of the integral cross section and of the s-wave phase shift. As expected the fixed-nuclei cross section and annihilation parameter (Z{sub eff}) present the same energy dependence at very low impact energies. As the virtual state energy approachesmore » zero, the magnitude of both cross section and Z{sub eff} are extremely enhanced (at zero impact energy). The possibility of shifting from a low-lying virtual state to a shallow bound state is not expected to significantly affect room-temperature annihilation rates.« less

  2. Preliminary research on virtual thermal comfort of automobile occupants

    NASA Astrophysics Data System (ADS)

    Horobet, Tiberiu; Danca, Paul; Nastase, Ilinca; Bode, Florin

    2018-02-01

    Numerical simulation of climate conditions in automotive industry for the study of thermal comfort had become more and more prominent in the last years compared with the classical approach which consists in wind tunnel measurements and field testing, the main advantages being the reduction of vehicle development time and costs. The study presented in this paper is a part of a project intended to evaluate different strategies of cabin ventilation for improving the thermal comfort inside vehicles. A virtual thermal manikin consisting of 24 parts was introduced on the driver seat in a vehicle. A heat load calculated for summer condition in the city of Cluj-Napoca, Romania was imposed as boundary condition. The purpose of this study was to elaborate a virtual thermal manikin suitable for our research, introduction of the manikin inside the vehicle and to examine his influence inside the automobile. The thermal comfort of the virtual manikin was evaluated in terms of temperature and air velocity.

  3. Tropospheric temperature measurements using a rotational raman lidar

    NASA Astrophysics Data System (ADS)

    Lee, Robert Benjamin, III

    Using the Hampton University (HU) Mie and Raman lidar, tropospheric temperature profiles were inferred from lidar measurements of anti-Stokes rotational Raman (RR) backscattered laser light from atmospheric nitrogen and oxygen molecules. The molecules were excited by 354.7 nanometer (nm) laser light emitted by the HU lidar. Averaged over 60-minute intervals, RR backscattered signals were detected in narrow 353.35 nm and 354.20 nm spectral bands with full-widths-at-half-maxima (FWHM) of 0.3 nm. During the special April 19-30, 2012, Ground-Based Remote Atmospheric Sounding Program (GRASP) campaign, the lidar temperature calibration coefficients were empirically derived using linear least squares and second order polynomial analyses of the lidar backscattered RR signals and of reference temperature profiles, obtained from radiosondes. The GRASP radiosondes were launched within 400 meters of the HU lidar site. Lidar derived temperature profiles were obtained at altitudes from the surface to over 18 kilometers (km) at night, and up to 5 km during the day. Using coefficients generated from least squares analyses, nighttime profiles were found to agree with profiles from reference radiosonde measurements within 3 K, at altitudes between 4 km and 9 km. Coefficients generated from the second order analyses yielded profiles which agreed with the reference profiles within 1 K uncertainty level in the 4 km to 10 km altitude region. Using profiles from GRASP radiosondes, the spatial and temporal homogeneities of the atmosphere, over HU, were estimated at the 1.5 K level within a 10 km radius of HU, and for observational periods approaching 3 hours. Theoretical calibration coefficients were derived from the optical and physical properties of the HU RR lidar and from the spectroscopic properties of atmospheric molecular nitrogen and oxygen. The theoretical coefficients along with lidar measurements of sky background radiances were used to evaluate the temporal stability of the empirically derived temperature profiles from the RR lidar measurements. The evaluations revealed systematic drifts in the coefficients. Frequent reference radiosonde temperature profiles should be used to correct for the drifts in the coefficients. For the first time, the cause of the coefficient drifts has been identified as the differences in the aging of the spectral responses of the HU lidar detector pairs. For the first time, the use of lidar sky background measurements was demonstrated as a useful technique to correct for the coefficient drift. This research should advance the derivations of lidar temperature calibration coefficients which can be used for long observational periods of temperature fields without the need for frequent lidar calibrations using radiosondes.

  4. Raising of Operating a Motor Vehicle Effects on Environment in Winter

    NASA Astrophysics Data System (ADS)

    Ertman, S. A.; Ertman, J. A.; Zakharov, D. A.

    2016-08-01

    Severe low-temperature conditions, in which considerable part of Russian Motor Park is operated, affect vehicles negatively. Cold weather causes higher fuel consumption and C02 emissions always. It is because of temperature profile changing of automobile motors, other systems and materials. For enhancement of car operation efficiency in severe winter environment the dependency of engine warm-up and cooling time on ambient air temperature and wind speed described by multifactorial mathematical models is established. -On the basis of experimental research it was proved that the coolant temperature constitutes the engine representative temperature and may be used as representative temperature of engine at large. The model of generation of integrated index for vehicle adaptability to winter operating conditions by temperature profile of engines was developed. the method for evaluation of vehicle adaptability to winter operating conditions by temperature profile of engines allows to decrease higher fuel consumption in cold climate.

  5. A Mathematical Model for the Exhaust Gas Temperature Profile of a Diesel Engine

    NASA Astrophysics Data System (ADS)

    Brito, C. H. G.; Maia, C. B.; Sodré, J. R.

    2015-09-01

    This work presents a heat transfer model for the exhaust gas of a diesel power generator to determine the gas temperature profile in the exhaust pipe. The numerical methodology to solve the mathematical model was developed using a finite difference method approach for energy equation resolution and determination of temperature profiles considering turbulent fluid flow and variable fluid properties. The simulation was carried out for engine operation under loads from 0 kW to 40 kW. The model was compared with results obtained using the multidimensional Ansys CFX software, which was applied to solve the governor equations of turbulent fluid flow. The results for the temperature profiles in the exhaust pipe show a good proximity between the mathematical model developed and the multidimensional software.

  6. Using Interactive Technology to Support Students' Understanding of the Greenhouse Effect and Global Warming

    NASA Astrophysics Data System (ADS)

    Varma, Keisha; Linn, Marcia C.

    2012-08-01

    In this work, we examine middle school students' understanding of the greenhouse effect and global warming. We designed and refined a technology-enhanced curriculum module called Global Warming: Virtual Earth. In the module activities, students conduct virtual experiments with a visualization of the greenhouse effect. They analyze data and draw conclusions about how individual variables effect changes in the Earth's temperature. They also carry out inquiry activities to make connections between scientific processes, the socio-scientific issues, and ideas presented in the media. Results show that participating in the unit increases students' understanding of the science. We discuss how students integrate their ideas about global climate change as a result of using virtual experiments that allow them to explore meaningful complexities of the climate system.

  7. The Implications of 3D Thermal Structure on 1D Atmospheric Retrieval

    NASA Astrophysics Data System (ADS)

    Blecic, Jasmina; Dobbs-Dixon, Ian; Greene, Thomas

    2017-10-01

    Using the atmospheric structure from a 3D global radiation-hydrodynamic simulation of HD 189733b and the open-source Bayesian Atmospheric Radiative Transfer (BART) code, we investigate the difference between the secondary-eclipse temperature structure produced with a 3D simulation and the best-fit 1D retrieved model. Synthetic data are generated by integrating the 3D models over the Spitzer, the Hubble Space Telescope (HST), and the James Web Space Telescope (JWST) bandpasses, covering the wavelength range between 1 and 11 μm where most spectroscopically active species have pronounced features. Using the data from different observing instruments, we present detailed comparisons between the temperature-pressure profiles recovered by BART and those from the 3D simulations. We calculate several averages of the 3D thermal structure and explore which particular thermal profile matches the retrieved temperature structure. We implement two temperature parameterizations that are commonly used in retrieval to investigate different thermal profile shapes. To assess which part of the thermal structure is best constrained by the data, we generate contribution functions for our theoretical model and each of our retrieved models. Our conclusions are strongly affected by the spectral resolution of the instruments included, their wavelength coverage, and the number of data points combined. We also see some limitations in each of the temperature parametrizations, as they are not able to fully match the complex curvatures that are usually produced in hydrodynamic simulations. The results show that our 1D retrieval is recovering a temperature and pressure profile that most closely matches the arithmetic average of the 3D thermal structure. When we use a higher resolution, more data points, and a parametrized temperature profile that allows more flexibility in the middle part of the atmosphere, we find a better match between the retrieved temperature and pressure profile and the arithmetic average. The Spitzer and HST simulated observations sample deep parts of the planetary atmosphere and provide fewer constraints on the temperature and pressure profile, while the JWST observations sample the middle part of the atmosphere, providing a good match with the middle and most complex part of the arithmetic average of the 3D temperature structure.

  8. Development of algorithmic decision-making models for sea crews

    NASA Astrophysics Data System (ADS)

    Lisitsyna, L.; Smetyuh, N.; Ivanovskiy, N.

    2018-05-01

    Modern virtual simulators are multifunctional, i.e. they can be used to develop and enhance the skills as well as to control professional skills and abilities of specialists of diverse profiles under various working conditions. This study is based on the generalization of a large experience in the sphere of applying ready-made multifunctional virtual simulators (MFVS) and developing new ones for the training and retraining of the crews of the Azov-Black Sea fishing vessels. The model is implemented in the multifunctional visual simulator "Trawling and purse-seining" to train the situational awareness among navigators individually and in a team. Interviews with those who employ the graduates of the advanced training courses testify to the adequacy of this model.

  9. Pharmacophore based approach to design inhibitors in crustaceans: an insight into the molt inhibition response to the receptor guanylyl cyclase.

    PubMed

    Shrivastava, Sajal; Princy, S Adline

    2014-04-01

    The first set of competitive inhibitors of molt inhibiting hormone (MIH) has been developed using the effective approaches such as Hip-Hop, virtual screening and manual alterations. Moreover, the conserved residues at 71 and 72 positions in the molt inhibiting hormone is known to be significant for selective inhibition of ecdysteroidogenesis; thus, the information from mutation and solution structure were used to generate common pharmacophore features. The geometry of the final six-feature pharmacophore was also found to be consistent with the homology-modeled MIH structures from various other decapod crustaceans. The Hypo-1, comprising six features hypothesis was carefully selected as a best pharmacophore model for virtual screening created on the basis of rank score and cluster processes. The hypothesis was validated and the database was virtually screened using this 3D query and the compounds were then manually altered to enhance the fit value. The hits obtained were further filtered for drug-likeness, which is expressed as physicochemical properties that contribute to favorable ADME/Tox profiles to eliminate the molecules exhibit toxicity and poor pharmacokinetics. In conclusion, the higher fit values of CI-1 (4.6), CI-4 (4.9) and CI-7 (4.2) in conjunction with better pharmacokinetic profile made these molecules practically helpful tool to increase production by accelerating molt in crustaceans. The use of feeding sub-therapeutic dosages of these growth enhancers can be very effectively implemented and certainly turn out to be a vital part of emerging nutritional strategies for economically important crustacean livestock.

  10. Determination of balloon gas mass and revised estimates of drag and virtual mass coefficients

    NASA Technical Reports Server (NTRS)

    Robbins, E.; Martone, M.

    1993-01-01

    In support of the NASA Balloon Program, small-scale balloons were flown with varying lifting gas and total system mass. Instrument packages were developed to measure and record acceleration and temperature data during these tests. Top fitting and instrument payload accelerations were measured from launch to steady state ascent and through ballast drop transients. The development of the small lightweight self-powered Stowaway Special instrument packages is discussed along with mathematical models developed to determine gas mass, drag and virtual mass coefficients.

  11. Statistical analysis of stratospheric temperature and ozone profile data for trends and model comparison

    NASA Technical Reports Server (NTRS)

    Tiao, G. C.

    1992-01-01

    Work performed during the project period July 1, 1990 to June 30, 1992 on the statistical analysis of stratospheric temperature data, rawinsonde temperature data, and ozone profile data for the detection of trends is described. Our principal topics of research are trend analysis of NOAA stratospheric temperature data over the period 1978-1989; trend analysis of rawinsonde temperature data for the period 1964-1988; trend analysis of Umkehr ozone profile data for the period 1977-1991; and comparison of observed ozone and temperature trends in the lower stratosphere. Analysis of NOAA stratospheric temperature data indicates the existence of large negative trends at 0.4 mb level, with magnitudes increasing with latitudes away from the equator. Trend analysis of rawinsonde temperature data over 184 stations shows significant positive trends about 0.2 C per decade at surface to 500 mb range, decreasing to negative trends about -0.3 C at 100 to 50 mb range, and increasing slightly at 30 mb level. There is little evidence of seasonal variation in trends. Analysis of Umkehr ozone data for 12 northern hemispheric stations shows significant negative trends about -.5 percent per year in Umkehr layers 7-9 and layer 3, but somewhat less negative trends in layers 4-6. There is no pronounced seasonal variation in trends, especially in layers 4-9. A comparison was made of empirical temperature trends from rawinsonde data in the lower stratosphere with temperature changes determined from a one-dimensional radiative transfer calculation that prescribed a given ozone change over the altitude region, surface to 50 km, obtained from trend analysis of ozonsonde and Umkehr profile data. The empirical and calculated temperature trends are found in substantive agreement in profile shape and magnitude.

  12. Coarse-Grained Model for Water Involving a Virtual Site.

    PubMed

    Deng, Mingsen; Shen, Hujun

    2016-02-04

    In this work, we propose a new coarse-grained (CG) model for water by combining the features of two popular CG water models (BMW and MARTINI models) as well as by adopting a topology similar to that of the TIP4P water model. In this CG model, a CG unit, representing four real water molecules, consists of a virtual site, two positively charged particles, and a van der Waals (vdW) interaction center. Distance constraint is applied to the bonds formed between the vdW interaction center and the positively charged particles. The virtual site, which carries a negative charge, is determined by the locations of the two positively charged particles and the vdW interaction center. For the new CG model of water, we coined the name "CAVS" (charge is attached to a virtual site) due to the involvment of the virtual site. After being tested in molecular dynamic (MD) simulations of bulk water at various time steps, under different temperatures and in different salt (NaCl) concentrations, the CAVS model offers encouraging predictions for some bulk properties of water (such as density, dielectric constant, etc.) when compared to experimental ones.

  13. Process-based modeling of temperature and water profiles in the seedling recruitment zone: Part I. Model validation

    USDA-ARS?s Scientific Manuscript database

    Process-based modeling provides detailed spatial and temporal information of the soil environment in the shallow seedling recruitment zone across field topography where measurements of soil temperature and water may not sufficiently describe the zone. Hourly temperature and water profiles within the...

  14. Development of a wear model for the wheel profile optimisation on railway vehicles

    NASA Astrophysics Data System (ADS)

    Ignesti, M.; Innocenti, A.; Marini, L.; Meli, E.; Rindi, A.

    2013-09-01

    The modelling and the reduction of wear due to wheel-rail interaction is a fundamental aspect in the railway field, mainly correlated to safety, maintenance interventions and costs. In this work, the authors present two innovative wheel profiles, specifically designed with the aim of improving the wear and stability behaviour of the standard ORE S1002 wheel profile matched with the UIC60 rail profile canted at 1/20 rad, which represents the wheel-rail combination adopted in the Italian railway line. The two wheel profiles, conventionally named CD1 and DR2, have been developed by the authors in collaboration with Trenitalia S.p.A. The CD1 profile has been designed with the purpose of spreading the contact points in the flange zone on a larger area in order to reduce wear phenomena and having a constant equivalent conicity for small lateral displacements of the wheelset with respect to the centred position in the track. The DR2 wheel profile is instead designed to guarantee the same kinematic characteristics of the matching formed by ORE S1002 wheel profile and UIC60 rail profile with laying angle α p equal to 1/40 rad, widely common in European railways and characterised by good performances in both wear and kinematic behaviour. The evolution of wheel profiles due to wear has been evaluated through a wear model developed and validated by the authors in previous works. The wear model comprises two mutually interactive units: a vehicle model for the dynamic simulations and a model for the wear assessment. The whole model is based on a discrete process: each discrete step consists in one dynamic simulation and one profile update by means of the wear model while, within the discrete step, the profiles are supposed to be constant. The choice of an appropriate step is crucial in terms of precision and computational effort: the particular strategy adopted in the current work has been chosen for its capacity in representing the nonlinear wear evolution and for the low computational time required. In the present research, the investigated trainset is the passenger vehicle ALSTOM ALn 501 'Minuetto', which is usually equipped with the standard ORE S1002 wheel profile in Italian railways. The entire model has been simulated on a virtual track specifically developed to represent a statistical description of the whole Italian line. The data necessary to build the virtual track and the vehicle model were provided by Trenitalia S.p.A. and Rete Ferroviaria Italiana. The CD1 and DR2 wheel profiles, matched to the UIC60 rail with cant 1/20 rad, have shown a good behaviour in terms of wear resistance if compared with the old ORE S1002 wheel profile, consequently assuring a more uniform distribution of the removed material and a prolongation of the mean time between two subsequent re-profiling interventions.

  15. LOFAR observations of the quiet solar corona

    NASA Astrophysics Data System (ADS)

    Vocks, C.; Mann, G.; Breitling, F.; Bisi, M. M.; Dąbrowski, B.; Fallows, R.; Gallagher, P. T.; Krankowski, A.; Magdalenić, J.; Marqué, C.; Morosan, D.; Rucker, H.

    2018-06-01

    Context. The quiet solar corona emits meter-wave thermal bremsstrahlung. Coronal radio emission can only propagate above that radius, Rω, where the local plasma frequency equals the observing frequency. The radio interferometer LOw Frequency ARray (LOFAR) observes in its low band (10-90 MHz) solar radio emission originating from the middle and upper corona. Aims: We present the first solar aperture synthesis imaging observations in the low band of LOFAR in 12 frequencies each separated by 5 MHz. From each of these radio maps we infer Rω, and a scale height temperature, T. These results can be combined into coronal density and temperature profiles. Methods: We derived radial intensity profiles from the radio images. We focus on polar directions with simpler, radial magnetic field structure. Intensity profiles were modeled by ray-tracing simulations, following wave paths through the refractive solar corona, and including free-free emission and absorption. We fitted model profiles to observations with Rω and T as fitting parameters. Results: In the low corona, Rω < 1.5 solar radii, we find high scale height temperatures up to 2.2 × 106 K, much more than the brightness temperatures usually found there. But if all Rω values are combined into a density profile, this profile can be fitted by a hydrostatic model with the same temperature, thereby confirming this with two independent methods. The density profile deviates from the hydrostatic model above 1.5 solar radii, indicating the transition into the solar wind. Conclusions: These results demonstrate what information can be gleaned from solar low-frequency radio images. The scale height temperatures we find are not only higher than brightness temperatures, but also than temperatures derived from coronograph or extreme ultraviolet (EUV) data. Future observations will provide continuous frequency coverage. This continuous coverage eliminates the need for local hydrostatic density models in the data analysis and enables the analysis of more complex coronal structures such as those with closed magnetic fields.

  16. Ant colony system algorithm for the optimization of beer fermentation control.

    PubMed

    Xiao, Jie; Zhou, Ze-Kui; Zhang, Guang-Xin

    2004-12-01

    Beer fermentation is a dynamic process that must be guided along a temperature profile to obtain the desired results. Ant colony system algorithm was applied to optimize the kinetic model of this process. During a fixed period of fermentation time, a series of different temperature profiles of the mixture were constructed. An optimal one was chosen at last. Optimal temperature profile maximized the final ethanol production and minimized the byproducts concentration and spoilage risk. The satisfactory results obtained did not require much computation effort.

  17. News: Virtual Enzymes

    EPA Science Inventory

    In biochemical systems a host of “nature’s catalysts” conduct chemical transformations at physiological temperatures, high substrate conversion, high optical activity integrity, and single reactive center substrate changes. All of these traits are highly esteemed in the pursuit o...

  18. Kinetic Profiling of Catalytic Organic Reactions as a Mechanistic Tool.

    PubMed

    Blackmond, Donna G

    2015-09-02

    The use of modern kinetic tools to obtain virtually continuous reaction progress data over the course of a catalytic reaction opens up a vista that provides mechanistic insights into both simple and complex catalytic networks. Reaction profiles offer a rate/concentration scan that tells the story of a batch reaction time course in a qualitative "fingerprinting" manner as well as in quantitative detail. Reaction progress experiments may be mathematically designed to elucidate catalytic rate laws from only a fraction of the number of experiments required in classical kinetic measurements. The information gained from kinetic profiles provides clues to direct further mechanistic analysis by other approaches. Examples from a variety of catalytic reactions spanning two decades of the author's work help to delineate nuances on a central mechanistic theme.

  19. A search for thermal excursions from ancient extraterrestrial impacts using Hadean zircon Ti-U-Th-Pb depth profiles.

    PubMed

    Abbott, Sunshine S; Harrison, T Mark; Schmitt, Axel K; Mojzsis, Stephen J

    2012-08-21

    Few terrestrial localities preserve more than a trace lithic record prior to ca. 3.8 Ga greatly limiting our understanding of the first 700 Ma of Earth history, a period inferred to have included a spike in the bolide flux to the inner solar system at ca. 3.85-3.95 Ga (the Late Heavy Bombardment, LHB). An accessible record of this era may be found in Hadean detrital zircons from the Jack Hills, Western Australia, in the form of μm-scale epitaxial overgrowths. By comparing crystallization temperatures of pre-3.8 Ga zircon overgrowths to the archive of zircon temperature spectra, it should, in principle, be possible to identify a distinctive impact signature. We have developed Ti-U-Th-Pb ion microprobe depth profiling to obtain age and temperature information within these zircon overgrowths and undertaken a feasibility study of its possible use in identifying impact events. Of eight grains profiled in this fashion, four have overgrowths of LHB-era age. Age vs. temperature profiles reveal a period between ca. 3.85-3.95 Ga (i.e., LHB era) characterized by significantly higher temperatures (approximately 840-875 °C) than do older or younger zircons or zircon domains (approximately 630-750 °C). However, temperatures approaching 900 °C can result in Pb isotopic exchange rendering interpretation of these profiles nonunique. Coupled age-temperature depth profiling shows promise in this role, and the preliminary data we report could represent the first terrestrial evidence for impact-related heating during the LHB.

  20. The effect of safety factor profile on transport in steady-state, high-performance scenarios

    DOE PAGES

    Holcomb, C. T.; Ferron, J. R.; Luce, T. C.; ...

    2012-03-09

    In this study, an analysis of the dependence of transport on the safety factor profile in high-performance, steady-state scenario discharges is presented. This is based on experimental scans of q 95 and q min taken with fixed β N, toroidal field, double-null plasma shape, divertor pumping, and electron cyclotron current drive input. The temperature and thermal diffusivity profiles were found to vary considerably with the q-profile, and these variations were significantly different for electrons and ions. With fixed q 95, both temperature profiles increase and broaden as q min is increased and the magnetic shear becomes low or negative inmore » the inner half radius, but these temperature profile changes are stronger for the electrons. Power balance calculations show the peak in the ion thermal diffusivity (χ i) at ρ – 0.6 – 0.8 increases with q 95 or q min.« less

  1. Evapotranspiration and microclimate at a low-level radioactive-waste disposal site in northwestern Illinois

    USGS Publications Warehouse

    Healy, R.W.; DeVries, M.P.; Sturrock, A.M.

    1987-01-01

    From July 1982 through June 1984, a study was made of the microclimate and evapotranspiration at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Vegetation at the site consists of mixed pasture grasses, primarily brome (Bromus inermis) and red clover (Trifoleum pratense). Three methods were used to estimate evapotranspiration: (1) an energy-budget with the Bowen ratio, (2) an aerodynamic-profile, and (3) a soil-based water-budget. For the aerodynamic-profile method, sensible-heat flux was estimated by a profile equation and evapotranspiration was then calculated as the residual in the energy-balance equation. Estimates by the energy-budget and aerodynamic-profile methods were computed from hourly data, then summed by days and months. Yearly estimates for March through November, by these methods, were quite close--648 and 626 millimeters, respectively. Daily estimates range up to a maximum of about 6 millimeters. The water-budget method produced only monthly estimates based on weekly or biweekly soil-moisture content measurements. The yearly evapotranspiration estimated by this method (which actually included only the months of April through October) was 655 millimeters. The March-through-November average for the three methods of 657 millimeters was equivalent to 70 percent of precipitation. Continuous measurements were made of incoming and reflected shortwave radiation, incoming and emitted longwave radiation, net radiation, soil-heat flux, soil temperature, horizontal windspeed, and wet- and dry-bulb air temperature. Windspeed and air temperature were measured at heights of 0.5 and 2.0 meters (and also at 1.0 meter after September 1983). Soil-moisture content of the soil zone was measured with a gamma-attenuation gage. Annual precipitation (938 millimeters) and average temperature (10.8 degrees Celsius) were virtually identical to long-term averages from nearby National Weather Service stations. Solar radiation averaged 65 percent of that normally expected under clear skies. Net radiation averaged 70.1 watts per square meter and was highest in July and negative during some winter months. Wind direction varied but was predominately out of the south-southeast. Wind speed at the 2-meter height averaged 3.5 meters per second and was slightly higher in winter months than the rest of the year. The amount of water stored within the soil zone was greatest in early spring and least in late summer. Seasonal and diurnal trends in evapotranspiration rates mirrored those in net radiation; July was usually the month with the highest rate. The ratio of sensible- to latent-heat fluxes (commonly called the Bowen ratio) for the 2-year period was 0.38, as averaged from the three methods. Monthly Bowen ratios fluctuated somewhat but averaged about 0.35 for late spring through summer. In fall, the ratio declined to zero or to slightly negative values. When the ratio was negative, the latent-heat flux was slightly greater than the net radiation because of additional energy supplied by the cooling soil and air. Evapotranspiration calculated by the three methods averaged 75 percent of potential evapotranspiration, as estimated by the Penman equation. There was no apparent seasonal trend in the relation between actual and potential evapotranspiration rates.

  2. Thermal modeling of the lithium/polymer battery

    NASA Astrophysics Data System (ADS)

    Pals, C. R.

    1994-10-01

    Research in the area of advanced batteries for electric-vehicle applications has increased steadily since the 1990 zero-emission-vehicle mandate of the California Air Resources Board. Due to their design flexibility and potentially high energy and power densities, lithium/polymer batteries are an emerging technology for electric-vehicle applications. Thermal modeling of lithium/polymer batteries is particularly important because the transport properties of the system depend exponentially on temperature. Two models have been presented for assessment of the thermal behavior of lithium/polymer batteries. The one-cell model predicts the cell potential, the concentration profiles, and the heat-generation rate during discharge. The cell-stack model predicts temperature profiles and heat transfer limitations of the battery. Due to the variation of ionic conductivity and salt diffusion coefficient with temperature, the performance of the lithium/polymer battery is greatly affected by temperature. Because of this variation, it is important to optimize the cell operating temperature and design a thermal management system for the battery. Since the thermal conductivity of the polymer electrolyte is very low, heat is not easily conducted in the direction perpendicular to cell layers. Temperature profiles in the cells are not as significant as expected because heat-generation rates in warmer areas of the cell stack are lower than heat-generation rates in cooler areas of the stack. This nonuniform heat-generation rate flattens the temperature profile. Temperature profiles as calculated by this model are not as steep as those calculated by previous models that assume a uniform heat-generation rate.

  3. Improving post-stroke cognitive and behavioral abnormalities by using virtual reality: A case report on a novel use of nirvana.

    PubMed

    De Luca, Rosaria; Torrisi, Michele; Piccolo, Adriana; Bonfiglio, Giovanni; Tomasello, Provvidenza; Naro, Antonino; Calabrò, Rocco Salvatore

    2017-10-11

    Cognitive impairment, as well as mood and anxiety disorders, occur frequently in patients following stroke. Aim of this study was to evaluate the effects of a combined rehabilitative treatment using conventional relaxation and respiratory techniques, in a specific rehabilitative virtual environment (by using Bts-Nirvana). A 58-year-old woman, affected by hemorrhagic stroke, underwent two different rehabilitation trainings, including either standard relaxation techniques alone in a common clinical setting or the same psychological approach in a semi-immersive virtual environment with an augmented sensorial (audio-video) and motor feedback (sensory motor-interaction). We evaluated the patient's cognitive and psychological profile before and after the two different trainings, by using a specific psychometric battery, aimed to assess cognitive status, attention processes and to estimate the presence of mood alterations, anxiety and coping strategies. Only at the end of the combined approach, we observed a significant improvement in attention and memory functions, with a nearly complete relief of anxiety symptoms and an improvement in coping strategies. Relaxation and respiratory techniques in a semi-immersive virtual reality environment, using Bts-Nirvana, may be a promising tool in improving attention process, coping strategies, and anxiety in individuals with neurological disorders, including stroke.

  4. Modeling virtual organizations with Latent Dirichlet Allocation: a case for natural language processing.

    PubMed

    Gross, Alexander; Murthy, Dhiraj

    2014-10-01

    This paper explores a variety of methods for applying the Latent Dirichlet Allocation (LDA) automated topic modeling algorithm to the modeling of the structure and behavior of virtual organizations found within modern social media and social networking environments. As the field of Big Data reveals, an increase in the scale of social data available presents new challenges which are not tackled by merely scaling up hardware and software. Rather, they necessitate new methods and, indeed, new areas of expertise. Natural language processing provides one such method. This paper applies LDA to the study of scientific virtual organizations whose members employ social technologies. Because of the vast data footprint in these virtual platforms, we found that natural language processing was needed to 'unlock' and render visible latent, previously unseen conversational connections across large textual corpora (spanning profiles, discussion threads, forums, and other social media incarnations). We introduce variants of LDA and ultimately make the argument that natural language processing is a critical interdisciplinary methodology to make better sense of social 'Big Data' and we were able to successfully model nested discussion topics from forums and blog posts using LDA. Importantly, we found that LDA can move us beyond the state-of-the-art in conventional Social Network Analysis techniques. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Novel Virtual User Models of Mild Cognitive Impairment for Simulating Dementia

    PubMed Central

    Segkouli, Sofia; Tzovaras, Dimitrios; Tsakiris, Thanos; Tsolaki, Magda; Karagiannidis, Charalampos

    2015-01-01

    Virtual user modeling research has attempted to address critical issues of human-computer interaction (HCI) such as usability and utility through a large number of analytic, usability-oriented approaches as cognitive models in order to provide users with experiences fitting to their specific needs. However, there is demand for more specific modules embodied in cognitive architecture that will detect abnormal cognitive decline across new synthetic task environments. Also, accessibility evaluation of graphical user interfaces (GUIs) requires considerable effort for enhancing ICT products accessibility for older adults. The main aim of this study is to develop and test virtual user models (VUM) simulating mild cognitive impairment (MCI) through novel specific modules, embodied at cognitive models and defined by estimations of cognitive parameters. Well-established MCI detection tests assessed users' cognition, elaborated their ability to perform multitasks, and monitored the performance of infotainment related tasks to provide more accurate simulation results on existing conceptual frameworks and enhanced predictive validity in interfaces' design supported by increased tasks' complexity to capture a more detailed profile of users' capabilities and limitations. The final outcome is a more robust cognitive prediction model, accurately fitted to human data to be used for more reliable interfaces' evaluation through simulation on the basis of virtual models of MCI users. PMID:26339282

  6. Soil Temperature and Moisture Profile (STAMP) System Handbook

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

    Cook, David R.

    The soil temperature and moisture profile system (STAMP) provides vertical profiles of soil temperature, soil water content (soil-type specific and loam type), plant water availability, soil conductivity, and real dielectric permittivity as a function of depth below the ground surface at half-hourly intervals, and precipitation at one-minute intervals. The profiles are measured directly by in situ probes at all extended facilities of the SGP climate research site. The profiles are derived from measurements of soil energy conductivity. Atmospheric scientists use the data in climate models to determine boundary conditions and to estimate the surface energy flux. The data are alsomore » useful to hydrologists, soil scientists, and agricultural scientists for determining the state of the soil. The STAMP system replaced the SWATS system in early 2016.« less

  7. Shoulder Kinematics and Spatial Pattern of Trapezius Electromyographic Activity in Real and Virtual Environments

    PubMed Central

    Samani, Afshin; Pontonnier, Charles; Dumont, Georges; Madeleine, Pascal

    2015-01-01

    The design of an industrial workstation tends to include ergonomic assessment steps based on a digital mock-up and a virtual reality setup. Lack of interaction and system fidelity is often reported as a main issue in such virtual reality applications. This limitation is a crucial issue as thorough ergonomic analysis is required for an investigation of the biomechanics. In the current study, we investigated the biomechanical responses of the shoulder joint in a simulated assembly task for comparison with the biomechanical responses in virtual environments. Sixteen male healthy novice subjects performed the task on three different platforms: real (RE), virtual (VE), and virtual environment with force feedback (VEF) with low and high precision demands. The subjects repeated the task 12 times (i.e., 12 cycles). High density electromyography from the upper trapezius and rotation angles of the shoulder joint were recorded and split into the cycles. The angular trajectories and velocity profiles of the shoulder joint angles over a cycle were computed in 3D. The inter-subject similarity in terms of normalized mutual information on kinematics and electromyography was investigated. Compared with RE the task in VE and VEF was characterized by lower kinematic maxima. The inter-subject similarity in RE compared with intra-subject similarity across the platforms was lower in terms of movement trajectories and greater in terms of trapezius muscle activation. The precision demand resulted in lower inter- and intra-subject similarity across platforms. The proposed approach identifies biomechanical differences in the shoulder joint in both VE and VEF compared with the RE platform, but these differences are less marked in VE mostly due to technical limitations of co-localizing the force feedback system in the VEF platform. PMID:25768123

  8. Properties of ion temperature gradient and trapped electron modes in tokamak plasmas with inverted density profiles

    NASA Astrophysics Data System (ADS)

    Du, Huarong; Jhang, Hogun; Hahm, T. S.; Dong, J. Q.; Wang, Z. X.

    2017-12-01

    We perform a numerical study of linear stability of the ion temperature gradient (ITG) mode and the trapped electron mode (TEM) in tokamak plasmas with inverted density profiles. A local gyrokinetic integral equation is applied for this study. From comprehensive parametric scans, we obtain stability diagrams for ITG modes and TEMs in terms of density and temperature gradient scale lengths. The results show that, for the inverted density profile, there exists a normalized threshold temperature gradient above which the ITG mode and the TEM are either separately or simultaneously unstable. The instability threshold of the TEM for the inverted density profile is substantially different from that for normal and flat density profiles. In addition, deviations are found on the ITG threshold from an early analytic theory in sheared slab geometry with the adiabatic electron response [T. S. Hahm and W. M. Tang, Phys. Fluids B 1, 1185 (1989)]. A possible implication of this work on particle transport in pellet fueled tokamak plasmas is discussed.

  9. Experimental study on temperature profile of fixed - bed gasification of oil-palm fronds

    NASA Astrophysics Data System (ADS)

    Atnaw, Samson M.; Sulaiman, Shaharin A.; Moni, M. Nazmi Z.

    2012-06-01

    Currently the world's second largest palm oil producer Malaysia produces large amount of oil palm biomass each year. The abundance of the biomass introduces a challenge to utilize them as main feedstock for heat and energy generation. Although some oil palm parts and derivatives like empty fruit bunch and fibre have been commercialized as fuel, less attention has been given to oil palm fronds (OPF). Initial feasibility and characterization studies of OPF showed that it is highly feasible as fuel for gasification to produce high value gaseous fuel or syngas. This paper discusses the experimental gasification attempt carried out on OPF using a 50 kW lab scale downdraft gasifier and its results. The conducted study focused on the temperature distributions within the reactor and the characteristics of the dynamic temperature profile for each temperature zones during operation. OPF feedstock of one cubic inch in individual size with 15% average moisture content was utilized. An average pyrolysis zone temperature of 324°Cand an average oxidation zone temperature of 796°Cwere obtained over a total gasification period of 74 minutes. A maximum oxidation zone temperature of 952°Cwas obtained at 486 lpm inlet air flow rate and 10 kg/hr feedstock consumption rate. Stable bluish flare was produced for more than 70% of the total gasification time. The recorded temperature profiles produced closely similar patterns with the temperature profiles recorded from the gasification of woody materials. Similar temperature profile was obtained comparing the results from OPF gasification with that of woody biomass. Furthermore, the successful ignition of the syngas produced from OPF gasification ascertained that OPF indeed has a higher potential as gasification feedstock. Hence, more detailed studies need to be done for better understanding in exploiting the biomass as a high prospect alternative energy solution. In addition, a study of the effect of initial moisture content of OPF feedstock on the temperature distribution profile along the gasifier bed showed that initial moisture content of feedstock in the range of 15% gives satisfactory result, while experiment with feedstock having higher moisture content resulted in lower zone temperature values.

  10. The Invisible Obstacle to Educational Equality: Gender Bias in Textbooks

    ERIC Educational Resources Information Center

    Blumberg, Rae Lesser

    2008-01-01

    Gender bias in textbooks (GBIT) is a low-profile education issue, given the 72,000,000 children who still have no access to schooling, but this article argues that GBIT is: (1) an important, (2) near-universal, (3) remarkably uniform, (4) quite persistent but (5) virtually invisible obstacle on the road to gender equality in education--an obstacle…

  11. Examination of the gamma equilibrium point hypothesis when applied to single degree of freedom movements performed with different inertial loads.

    PubMed

    Bellomo, A; Inbar, G

    1997-01-01

    One of the theories of human motor control is the gamma Equilibrium Point Hypothesis. It is an attractive theory since it offers an easy control scheme where the planned trajectory shifts monotionically from an initial to a final equilibrium state. The feasibility of this model was tested by reconstructing the virtual trajectory and the stiffness profiles for movements performed with different inertial loads and examining them. Three types of movements were tested: passive movements, targeted movements, and repetitive movements. Each of the movements was performed with five different inertial loads. Plausible virtual trajectories and stiffness profiles were reconstructed based on the gamma Equilibrium Point Hypothesis for the three different types of movements performed with different inertial loads. However, the simple control strategy supported by the model, where the planned trajectory shifts monotonically from an initial to a final equilibrium state, could not be supported for targeted movements performed with added inertial load. To test the feasibility of the model further we must examine the probability that the human motor control system would choose a trajectory more complicated than the actual trajectory to control.

  12. [The theme of disaster in health care: profile of technical and scientific production in the specialized database on disasters of the Virtual Health Library - VHL].

    PubMed

    Rocha, Vania; Ximenes, Elisa Francioli; Carvalho, Mauren Lopes de; Alpino, Tais de Moura Ariza; Freitas, Carlos Machado de

    2014-09-01

    In the specialized database of the Virtual Health Library (VHL), the DISASTER database highlights the importance of the theme for the health sector. The scope of this article is to identify the profiles of technical and scientific publications in the specialized database. Based on systematic searches and the analysis of results it is possible to determine: the type of publication; the main topics addressed; the most common type of disasters mentioned in published materials, countries and regions as subjects, historic periods with the most publications and the current trend of publications. When examining the specialized data in detail, it soon becomes clear that the number of major topics is very high, making a specific search process in this database a challenging exercise. On the other hand, it is encouraging that the disaster topic is discussed and assessed in a broad and diversified manner, associated with different aspects of the natural and social sciences. The disaster issue requires the production of interdisciplinary knowledge development to reduce the impacts of disasters and for risk management. In this way, since the health sector is a interdisciplinary area, it can contribute to knowledge production.

  13. The Pursuit of Romantic Alternatives Online: Social Media Friends as Potential Alternatives.

    PubMed

    Abbasi, Irum Saeed; Alghamdi, Nawal G

    2018-01-02

    What causes some marriages to stand the test of time while others fail? Marital commitment is the key force underlying the stability, quality, and longevity of the romantic relationship. Commitment is strengthened in the presence of marital satisfaction, the absence of alternative attractions, and steady investments made in the relationship. Commitment is also a consequence of increasing dependence. When partners are emotionally engaged with their virtual connections, their dependence on the significant other decreases. On the contrary, dependence on the partner increases when people feel satisfied with their relationship, think unfavorably about the quality of available alternatives, and feel that they have made great investments in their relationship. Technological advancements of the present era have spawned a wide array of social networking sites (SNSs) that display boastfully curated profiles of virtual connections. These overly glossed profiles may lead social media users to feel deficient in their lives. Previous research has shown that Facebook use can reduce relationship satisfaction by providing potential romantic alternatives and deflecting time and emotional investments away from the committed relationship. This article examines the commitment literature and discusses how commitment is undermined in the contemporary era. Finally, marital therapy is addressed with suggestions for future areas of exploration.

  14. Measuring Convective Mass Fluxes Over Tropical Oceans

    NASA Astrophysics Data System (ADS)

    Raymond, David

    2017-04-01

    Deep convection forms the upward branches of all large-scale circulations in the tropics. Understanding what controls the form and intensity of vertical convective mass fluxes is thus key to understanding tropical weather and climate. These mass fluxes and the corresponding conditions supporting them have been measured by recent field programs (TPARC/TCS08, PREDICT, HS3) in tropical disturbances considered to be possible tropical storm precursors. In reality, this encompasses most strong convection in the tropics. The measurements were made with arrays of dropsondes deployed from high altitude. In some cases Doppler radar provided additional measurements. The results are in some ways surprising. Three factors were found to control the mass flux profiles, the strength of total surface heat fluxes, the column-integrated relative humidity, and the low to mid-tropospheric moist convective instability. The first two act as expected, with larger heat fluxes and higher humidity producing more precipitation and stronger lower tropospheric mass fluxes. However, unexpectedly, smaller (but still positive) convective instability produces more precipitation as well as more bottom-heavy convective mass flux profiles. Furthermore, the column humidity and the convective instability are anti-correlated, at least in the presence of strong convection. On spatial scales of a few hundred kilometers, the virtual temperature structure appears to be in dynamic balance with the pattern of potential vorticity. Since potential vorticity typically evolves on longer time scales than convection, the potential vorticity pattern plus the surface heat fluxes then become the immediate controlling factors for average convective properties. All measurements so far have taken place in regions with relatively flat sea surface temperature (SST) distributions. We are currently seeking funding for a measurement program in the tropical east Pacific, a region that exhibits strong SST gradients and correspondingly great diversity in the forms of convection. Given the strong boundary layer flows induced by the SST gradients in this region, we hope to determine whether the patterns of convective mass flux seen in other regions persist there.

  15. [Self-rating of oral health according to the Oral Health Impact Profile and associated factors: a systematic review].

    PubMed

    Gabardo, Marilisa Carneiro Leão; Moysés, Simone Tetu; Moysés, Samuel Jorge

    2013-06-01

    To systematically evaluate the literature to investigate associations between social, demographic, economic, psychosocial, and behavioral factors and the self-perception of oral health measured using the Oral Health Impact Profile (OHIP). In this systematic review of the literature, the Preferred Reporting Items for Systematic Reviews (PRISMA) were adapted for the performance of a qualitative metasummary, without meta-analysis. Articles about oral health and associated factors with implications for quality of life were selected, with a focus on the tool for self-rating of the oral health-disease process, the OHIP. Pubmed/National Library of Medicine (NLM) and the Virtual Health Library (Biblioteca Virtual em Saúde - BVS/BIREME) were searched. Articles published between 2001 and 2011 were included. The following Medical Subject Headings (MeSH) were employed: oral health, quality of life, sickness impact profile, and socioeconomic factors. Of 57 articles identified, 20 met the inclusion criteria. The metasummary revealed that a poor self-perception of oral health was associated with unfavorable social, economic, demographic, and psychosocial factors, as well as with undesirable habits and poor clinical oral conditions. There is consensus in the literature about the influence of the investigated factors on the self-perception of oral health and on quality of life. The OHIP is an important aid for determining oral health needs and for developing strategies to control/reduce disease and promote oral health, with a consequent positive impact on quality of life.

  16. Singularity in the positive Hall coeffcient near pre-onset temperatures in high-Tc superconductors

    NASA Astrophysics Data System (ADS)

    Vezzoli, G. C.; Chen, M. F.; Craver, F.; Moon, B. M.; Safari, A.; Burke, T.; Stanley, W.

    1990-10-01

    Hall measurements using continuous extremely slow cooling and reheating rates as well as employing eqiulibrium point-by-point conventional techniques reveals a clear anomally in RH at pre-onset temperatures near Tc in polycrystalline samples Y1Ba2Cu3O7 and Bi2Sr2Ca2Cu3O10. The anomaly has the appearance of a singularity of Dirac-delta function which parallels earlier work on La1-xSrxCuO4. Recent single crystal work on the Bi-containing high-Tc superconductor is in accord with a clearcut anomaly. The singularity is tentatively interpreted to be associated (upon cooling) with initially the removal of positive holes from the hopping conduction system of the normal state such as from the increased concentration of bound virtual excitons due to increased exciton and hole lifetimes at low temperature. Subsequently the formation of Cooper pairs by mediation from these centers (bound-holes) and/or bound excitons) may cause an ionization of these bound virtual excitons thereby re-introducing holes and electrons into the conduction system at Tc.

  17. Optimal Detection of Global Warming using Temperature Profiles

    NASA Technical Reports Server (NTRS)

    Leroy, Stephen S.

    1997-01-01

    Optimal fingerprinting is applied to estimate the amount of time it would take to detect warming by increased concentrations of carbon dioxide in monthly averages of temperature profiles over the Indian Ocean.

  18. Dynamic temperature and humidity environmental profiles: impact for future emergency and disaster preparedness and response.

    PubMed

    Ferguson, William J; Louie, Richard F; Tang, Chloe S; Paw U, Kyaw Tha; Kost, Gerald J

    2014-02-01

    During disasters and complex emergencies, environmental conditions can adversely affect the performance of point-of-care (POC) testing. Knowledge of these conditions can help device developers and operators understand the significance of temperature and humidity limits necessary for use of POC devices. First responders will benefit from improved performance for on-site decision making. To create dynamic temperature and humidity profiles that can be used to assess the environmental robustness of POC devices, reagents, and other resources (eg, drugs), and thereby, to improve preparedness. Surface temperature and humidity data from the National Climatic Data Center (Asheville, North Carolina USA) was obtained, median hourly temperature and humidity were calculated, and then mathematically stretched profiles were created to include extreme highs and lows. Profiles were created for: (1) Banda Aceh, Indonesia at the time of the 2004 Tsunami; (2) New Orleans, Louisiana USA just before and after Hurricane Katrina made landfall in 2005; (3) Springfield, Massachusetts USA for an ambulance call during the month of January 2009; (4) Port-au-Prince, Haiti following the 2010 earthquake; (5) Sendai, Japan for the March 2011 earthquake and tsunami with comparison to the colder month of January 2011; (6) New York, New York USA after Hurricane Sandy made landfall in 2012; and (7) a 24-hour rescue from Hawaii USA to the Marshall Islands. Profiles were validated by randomly selecting 10 days and determining if (1) temperature and humidity points fell inside and (2) daily variations were encompassed. Mean kinetic temperatures (MKT) were also assessed for each profile. Profiles accurately modeled conditions during emergency and disaster events and enclosed 100% of maximum and minimum temperature and humidity points. Daily variations also were represented well with 88.6% (62/70) of temperature readings and 71.1% (54/70) of relative humidity readings falling within diurnal patterns. Days not represented well primarily had continuously high humidity. Mean kinetic temperature was useful for severity ranking. Simulating temperature and humidity conditions clearly reveals operational challenges encountered during disasters and emergencies. Understanding of environmental stresses and MKT leads to insights regarding operational robustness necessary for safe and accurate use of POC devices and reagents. Rescue personnel should understand these principles before performing POC testing in adverse environments.

  19. Visualized modeling platform for virtual plant growth and monitoring on the internet

    NASA Astrophysics Data System (ADS)

    Zhou, De-fu; Tian, Feng-qui; Ren, Ping

    2009-07-01

    Virtual plant growth is a key research topic in Agriculture Information Technique and Computer Graphics. It has been applied in botany, agronomy, environmental sciences, computre sciences and applied mathematics. Modeling leaf color dynamics in plant is of significant importance for realizing virtual plant growth. Using systematic analysis method and dynamic modeling technology, a SPAD-based leaf color dynamic model was developed to simulate time-course change characters of leaf SPAD on the plant. In addition, process of plant growth can be computer-stimulated using Virtual Reality Modeling Language (VRML) to establish a vivid and visible model, including shooting, rooting, blooming, as well as growth of the stems and leaves. In the resistance environment, e.g., lacking of water, air or nutrient substances, high salt or alkaline, freezing injury, high temperature, suffering from diseases and insect pests, the changes from the level of whole plant to organs, tissues and cells could be computer-stimulated. Changes from physiological and biochemistry could also be described. When a series of indexes were input by the costumers, direct view and microcosmic changes could be shown. Thus, the model has a good performance in predicting growth condition of the plant, laying a foundation for further constructing virtual plant growth system. The results revealed that realistic physiological and pathological processes of 3D virtual plants could be demonstrated by proper design and effectively realized in the internet.

  20. Environmental profile and critical temperature effects on milk production of Holstein cows in desert climate

    NASA Astrophysics Data System (ADS)

    Igono, M. O.; Bjotvedt, G.; Sanford-Crane, H. T.

    1992-06-01

    The environmental profile of central Arizona is quantitatively described using meteorological data between 1971 and 1986. Utilizing ambient temperature criteria of hours per day less than 21° C, between 21 and 27° C, and more than 27° C, the environmental profile of central Arizona consists of varying levels of thermoneutral and heat stress periods. Milk production data from two commercial dairy farms from March 1990 to February 1991 were used to evaluate the seasonal effects identified in the environmental profile. Overall, milk production is lower during heat stress compared to thermoneutral periods. During heat stress, the cool period of hours per day with temperature less than 21° C provides a margin of safety to reduce the effects of heat stress on decreased milk production. Using minimum, mean and maximum ambient temperatures, the upper critical temperatures for milk production are 21, 27 and 32° C, respectively. Using the temperature-humidity index as the thermal environment indicator, the critical values for minimum, mean and maximum THI are 64, 72 and 76, respectively.

  1. Simple laser vision sensor calibration for surface profiling applications

    NASA Astrophysics Data System (ADS)

    Abu-Nabah, Bassam A.; ElSoussi, Adnane O.; Al Alami, Abed ElRahman K.

    2016-09-01

    Due to the relatively large structures in the Oil and Gas industry, original equipment manufacturers (OEMs) have been implementing custom-designed laser vision sensor (LVS) surface profiling systems as part of quality control in their manufacturing processes. The rough manufacturing environment and the continuous movement and misalignment of these custom-designed tools adversely affect the accuracy of laser-based vision surface profiling applications. Accordingly, Oil and Gas businesses have been raising the demand from the OEMs to implement practical and robust LVS calibration techniques prior to running any visual inspections. This effort introduces an LVS calibration technique representing a simplified version of two known calibration techniques, which are commonly implemented to obtain a calibrated LVS system for surface profiling applications. Both calibration techniques are implemented virtually and experimentally to scan simulated and three-dimensional (3D) printed features of known profiles, respectively. Scanned data is transformed from the camera frame to points in the world coordinate system and compared with the input profiles to validate the introduced calibration technique capability against the more complex approach and preliminarily assess the measurement technique for weld profiling applications. Moreover, the sensitivity to stand-off distances is analyzed to illustrate the practicality of the presented technique.

  2. Method for Operating a Sensor to Differentiate Between Analytes in a Sample

    DOEpatents

    Kunt, Tekin; Cavicchi, Richard E; Semancik, Stephen; McAvoy, Thomas J

    1998-07-28

    Disclosed is a method for operating a sensor to differentiate between first and second analytes in a sample. The method comprises the steps of determining a input profile for the sensor which will enhance the difference in the output profiles of the sensor as between the first analyte and the second analyte; determining a first analyte output profile as observed when the input profile is applied to the sensor; determining a second analyte output profile as observed when the temperature profile is applied to the sensor; introducing the sensor to the sample while applying the temperature profile to the sensor, thereby obtaining a sample output profile; and evaluating the sample output profile as against the first and second analyte output profiles to thereby determine which of the analytes is present in the sample.

  3. Thermally induced stresses in cross-ply composite tubes

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Cooper, D. E.; Tompkins, S. S.

    1986-01-01

    An approximate solution for determining stresses in cross-ply composite tubes subjected to a circumferential temperature gradient is presented. The solution is based on the principle of complementary virtual work (PCVW) in conjunction with a Ritz approximation on the stress field and accounts for the temperature dependence of material properties. The PCVW method is compared with a planar elasticity solution using temperature-independent material properties and a Navier approach. The net effect of including temperature-dependent material properties is that the peak absolute values of the stresses are reduced. The dependence of the stresses on the circumferential location is also reduced in comparison with the case of temperature-independent properties.

  4. The thermal regime in the resurgent dome of Long Valley Caldera, California: Inferences from precision temperature logs in deep wells

    USGS Publications Warehouse

    Hurwitz, S.; Farrar, C.D.; Williams, C.F.

    2010-01-01

    Long Valley Caldera in eastern California formed 0.76Ma ago in a cataclysmic eruption that resulted in the deposition of 600km3 of Bishop Tuff. The total current heat flow from the caldera floor is estimated to be ~290MW, and a geothermal power plant in Casa Diablo on the flanks of the resurgent dome (RD) generates ~40MWe. The RD in the center of the caldera was uplifted by ~80cm between 1980 and 1999 and was explained by most models as a response to magma intrusion into the shallow crust. This unrest has led to extensive research on geothermal resources and volcanic hazards in the caldera. Here we present results from precise, high-resolution, temperature-depth profiles in five deep boreholes (327-1,158m) on the RD to assess its thermal state, and more specifically 1) to provide bounds on the advective heat transport as a guide for future geothermal exploration, 2) to provide constraints on the occurrence of magma at shallow crustal depths, and 3) to provide a baseline for future transient thermal phenomena in response to large earthquakes, volcanic activity, or geothermal production. The temperature profiles display substantial non-linearity within each profile and variability between the different profiles. All profiles display significant temperature reversals with depth and temperature gradients <50??C/km at their bottom. The maximum temperature in the individual boreholes ranges between 124.7??C and 129.5??C and bottom hole temperatures range between 99.4??C and 129.5??C. The high-temperature units in the three Fumarole Valley boreholes are at the approximate same elevation as the high-temperature unit in borehole M-1 in Casa Diablo indicating lateral or sub-lateral hydrothermal flow through the resurgent dome. Small differences in temperature between measurements in consecutive years in three of the wells suggest slow cooling of the shallow hydrothermal flow system. By matching theoretical curves to segments of the measured temperature profiles, we calculate horizontal groundwater velocities in the hydrothermal flow unit under the RD that range from 1.9 to 2.8m/yr, which corresponds to a maximum power flowing through the RD of 3-4MW. The relatively low temperatures and large isothermal segments at the bottom of the temperature profiles are inconsistent with the presence of magma at shallow crustal levels. ?? 2010.

  5. The thermal regime in the resurgent dome of Long Valley Caldera, California: Inferences from precision temperature logs in deep wells

    NASA Astrophysics Data System (ADS)

    Hurwitz, Shaul; Farrar, Christopher D.; Williams, Colin F.

    2010-12-01

    Long Valley Caldera in eastern California formed 0.76 Ma ago in a cataclysmic eruption that resulted in the deposition of 600 km 3 of Bishop Tuff. The total current heat flow from the caldera floor is estimated to be ~ 290 MW, and a geothermal power plant in Casa Diablo on the flanks of the resurgent dome (RD) generates ~40 MWe. The RD in the center of the caldera was uplifted by ~ 80 cm between 1980 and 1999 and was explained by most models as a response to magma intrusion into the shallow crust. This unrest has led to extensive research on geothermal resources and volcanic hazards in the caldera. Here we present results from precise, high-resolution, temperature-depth profiles in five deep boreholes (327-1,158 m) on the RD to assess its thermal state, and more specifically 1) to provide bounds on the advective heat transport as a guide for future geothermal exploration, 2) to provide constraints on the occurrence of magma at shallow crustal depths, and 3) to provide a baseline for future transient thermal phenomena in response to large earthquakes, volcanic activity, or geothermal production. The temperature profiles display substantial non-linearity within each profile and variability between the different profiles. All profiles display significant temperature reversals with depth and temperature gradients <50 °C/km at their bottom. The maximum temperature in the individual boreholes ranges between 124.7 °C and 129.5 °C and bottom hole temperatures range between 99.4 °C and 129.5 °C. The high-temperature units in the three Fumarole Valley boreholes are at the approximate same elevation as the high-temperature unit in borehole M-1 in Casa Diablo indicating lateral or sub-lateral hydrothermal flow through the resurgent dome. Small differences in temperature between measurements in consecutive years in three of the wells suggest slow cooling of the shallow hydrothermal flow system. By matching theoretical curves to segments of the measured temperature profiles, we calculate horizontal groundwater velocities in the hydrothermal flow unit under the RD that range from 1.9 to 2.8 m/yr, which corresponds to a maximum power flowing through the RD of 3-4 MW. The relatively low temperatures and large isothermal segments at the bottom of the temperature profiles are inconsistent with the presence of magma at shallow crustal levels.

  6. Impacts of temperature and lunar day on gene expression profiles during a monthly reproductive cycle in the brooding coral Pocillopora damicornis.

    PubMed

    Crowder, Camerron M; Meyer, Eli; Fan, Tung-Yung; Weis, Virginia M

    2017-08-01

    Reproductive timing in brooding corals has been correlated to temperature and lunar irradiance, but the mechanisms by which corals transduce these environmental variables into molecular signals are unknown. To gain insight into these processes, global gene expression profiles in the coral Pocillopora damicornis were examined (via RNA-Seq) across lunar phases and between temperature treatments, during a monthly planulation cycle. The interaction of temperature and lunar day together had the largest influence on gene expression. Mean timing of planulation, which occurred at lunar days 7.4 and 12.5 for 28- and 23°C-treated corals, respectively, was associated with an upregulation of transcripts in individual temperature treatments. Expression profiles of planulation-associated genes were compared between temperature treatments, revealing that elevated temperatures disrupted expression profiles associated with planulation. Gene functions inferred from homologous matches to online databases suggest complex neuropeptide signalling, with calcium as a central mediator, acting through tyrosine kinase and G protein-coupled receptor pathways. This work contributes to our understanding of coral reproductive physiology and the impacts of environmental variables on coral reproductive pathways. © 2017 John Wiley & Sons Ltd.

  7. Control of nanoparticle agglomeration through variation of the time-temperature profile in chemical vapor synthesis

    NASA Astrophysics Data System (ADS)

    Djenadic, Ruzica; Winterer, Markus

    2017-02-01

    The influence of the time-temperature history on the characteristics of nanoparticles such as size, degree of agglomeration, or crystallinity is investigated for chemical vapor synthesis (CVS). A simple reaction-coagulation-sintering model is used to describe the CVS process, and the results of the model are compared to experimental data. Nanocrystalline titania is used as model material. Titania nanoparticles are generated from titanium-tetraisopropoxide (TTIP) in a hot-wall reactor. Pure anatase particles and mixtures of anatase, rutile (up to 11 vol.%), and brookite (up to 29 vol.%) with primary particle sizes from 1.7 nm to 10.5 nm and agglomerate particle sizes from 24.3 nm to 55.6 nm are formed depending on the particle time-temperature history. An inductively heated furnace with variable inductor geometry is used as a novel system to control the time-temperature profile in the reactor externally covering a large wall temperature range from 873 K to 2023 K. An appropriate choice of inductor geometry, i.e. time-temperature profile, can significantly reduce the degree of agglomeration. Other particle characteristics such as crystallinity are also substantially influenced by the time-temperature profile.

  8. Temperature profiles measurements in turbulent Rayleigh-Bénard convection by optical fibre system at the Barrel of II-menau

    NASA Astrophysics Data System (ADS)

    Drahotský, Jakub; Hanzelka, Pavel; Musilová, Věra; Macek, Michal; du Puits, Ronald; Urban, Pavel

    2018-06-01

    Modelling of large-scale natural (thermally-generated) turbulent flows (such as the turbulent convection in Earth's atmosphere, oceans, or Sun) is approached in laboratory experiments in the simplified model system called the Rayleigh-Bénard convection (RBC). We present preliminary measurements of vertical temperature profiles in the cell with the height of 4:7 m, 7:15m in diameter, obtained at the Barrel of Ilmenau (BOI), the worldwide largest experimental setup to study highly turbulent RBC, newly equipped with the Luna ODiSI-B optical fibre system. In our configuration, the system permits to measure the temperature with a high spatial resolution of 5mm along a very thin glass optical fibre with the length of 5m and seems to be perfectly suited for measurement of time series of instantaneous vertical temperature profiles. The system was supplemented with the two Pt100 vertically movable probes specially designed by us for reference temperature profiles measurements.

  9. On the reduction of occultation light curves. [stellar occultations by planets

    NASA Technical Reports Server (NTRS)

    Wasserman, L.; Veverka, J.

    1973-01-01

    The two basic methods of reducing occultation light curves - curve fitting and inversion - are reviewed and compared. It is shown that the curve fitting methods have severe problems of nonuniqueness. In addition, in the case of occultation curves dominated by spikes, it is not clear that such solutions are meaningful. The inversion method does not suffer from these drawbacks. Methods of deriving temperature profiles from refractivity profiles are then examined. It is shown that, although the temperature profiles are sensitive to small errors in the refractivity profile, accurate temperatures can be obtained, particularly at the deeper levels of the atmosphere. The ambiguities that arise when the occultation curve straddles the turbopause are briefly discussed.

  10. World Ocean Database and the Global Temperature and Salinity Profile Program Database: Synthesis of historical and near real-time ocean profile data

    NASA Astrophysics Data System (ADS)

    Boyer, T.; Sun, L.; Locarnini, R. A.; Mishonov, A. V.; Hall, N.; Ouellet, M.

    2016-02-01

    The World Ocean Database (WOD) contains systematically quality controlled historical and recent ocean profile data (temperature, salinity, oxygen, nutrients, carbon cycle variables, biological variables) ranging from Captain Cooks second voyage (1773) to this year's Argo floats. The US National Centers for Environmental Information (NCEI) also hosts the Global Temperature and Salinity Profile Program (GTSPP) Continuously Managed Database (CMD) which provides quality controlled near-real time ocean profile data and higher level quality controlled temperature and salinity profiles from 1990 to present. Both databases are used extensively for ocean and climate studies. Synchronization of these two databases will allow easier access and use of comprehensive regional and global ocean profile data sets for ocean and climate studies. Synchronizing consists of two distinct phases: 1) a retrospective comparison of data in WOD and GTSPP to ensure that the most comprehensive and highest quality data set is available to researchers without the need to individually combine and contrast the two datasets and 2) web services to allow the constantly accruing near-real time data in the GTSPP CMD and the continuous addition and quality control of historical data in WOD to be made available to researchers together, seamlessly.

  11. CLASH-X: A Comparison of Lensing and X-Ray Techniques for Measuring the Mass Profiles of Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Donahue, Megan; Voit, G. Mark; Mahdavi, Andisheh; Umetsu, Keiichi; Ettori, Stefano; Merten, Julian; Postman, Marc; Hoffer, Aaron; Baldi, Alessandro; Coe, Dan; Czakon, Nicole; Bartelmann, Mattias; Benitez, Narciso; Bouwens, Rychard; Bradley, Larry; Broadhurst, Tom; Ford, Holland; Gastaldello, Fabio; Grillo, Claudio; Infante, Leopoldo; Jouvel, Stephanie; Koekemoer, Anton; Kelson, Daniel; Lahav, Ofer; Lemze, Doron; Medezinski, Elinor; Melchior, Peter; Meneghetti, Massimo; Molino, Alberto; Moustakas, John; Moustakas, Leonidas A.; Nonino, Mario; Rosati, Piero; Sayers, Jack; Seitz, Stella; Van der Wel, Arjen; Zheng, Wei; Zitrin, Adi

    2014-10-01

    We present profiles of temperature, gas mass, and hydrostatic mass estimated from new and archival X-ray observations of CLASH clusters. We compare measurements derived from XMM and Chandra observations with one another and compare both to gravitational lensing mass profiles derived with CLASH Hubble Space Telescope and Subaru Telescope lensing data. Radial profiles of Chandra and XMM measurements of electron density and enclosed gas mass are nearly identical, indicating that differences in hydrostatic masses inferred from X-ray observations arise from differences in gas-temperature measurements. Encouragingly, gas temperatures measured in clusters by XMM and Chandra are consistent with one another at ~100-200 kpc radii, but XMM temperatures systematically decline relative to Chandra temperatures at larger radii. The angular dependence of the discrepancy suggests that additional investigation on systematics such as the XMM point-spread function correction, vignetting, and off-axis responses is yet required. We present the CLASH-X mass-profile comparisons in the form of cosmology-independent and redshift-independent circular-velocity profiles. We argue that comparisons of circular-velocity profiles are the most robust way to assess mass bias. Ratios of Chandra hydrostatic equilibrium (HSE) mass profiles to CLASH lensing profiles show no obvious radial dependence in the 0.3-0.8 Mpc range. However, the mean mass biases inferred from the weak-lensing (WL) and SaWLens data are different. As an example, the weighted-mean value at 0.5 Mpc is langbrang = 0.12 for the WL comparison and langbrang = -0.11 for the SaWLens comparison. The ratios of XMM HSE mass profiles to CLASH lensing profiles show a pronounced radial dependence in the 0.3-1.0 Mpc range, with a weighted mean mass bias value rising to langbrang >~ 0.3 at ~1 Mpc for the WL comparison and langbrang ≈ 0.25 for the SaWLens comparison. The enclosed gas mass profiles from both Chandra and XMM rise to a value ≈1/8 times the total-mass profiles inferred from lensing at ≈0.5 Mpc and remain constant outside of that radius, suggesting that M gas × 8 profiles may be an excellent proxy for total-mass profiles at >~ 0.5 Mpc in massive galaxy clusters.

  12. CLASH-X: A comparison of lensing and X-ray techniques for measuring the mass profiles of galaxy clusters

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

    Donahue, Megan; Voit, G. Mark; Hoffer, Aaron

    2014-10-20

    We present profiles of temperature, gas mass, and hydrostatic mass estimated from new and archival X-ray observations of CLASH clusters. We compare measurements derived from XMM and Chandra observations with one another and compare both to gravitational lensing mass profiles derived with CLASH Hubble Space Telescope and Subaru Telescope lensing data. Radial profiles of Chandra and XMM measurements of electron density and enclosed gas mass are nearly identical, indicating that differences in hydrostatic masses inferred from X-ray observations arise from differences in gas-temperature measurements. Encouragingly, gas temperatures measured in clusters by XMM and Chandra are consistent with one another atmore » ∼100-200 kpc radii, but XMM temperatures systematically decline relative to Chandra temperatures at larger radii. The angular dependence of the discrepancy suggests that additional investigation on systematics such as the XMM point-spread function correction, vignetting, and off-axis responses is yet required. We present the CLASH-X mass-profile comparisons in the form of cosmology-independent and redshift-independent circular-velocity profiles. We argue that comparisons of circular-velocity profiles are the most robust way to assess mass bias. Ratios of Chandra hydrostatic equilibrium (HSE) mass profiles to CLASH lensing profiles show no obvious radial dependence in the 0.3-0.8 Mpc range. However, the mean mass biases inferred from the weak-lensing (WL) and SaWLens data are different. As an example, the weighted-mean value at 0.5 Mpc is (b) = 0.12 for the WL comparison and (b) = –0.11 for the SaWLens comparison. The ratios of XMM HSE mass profiles to CLASH lensing profiles show a pronounced radial dependence in the 0.3-1.0 Mpc range, with a weighted mean mass bias value rising to (b) ≳ 0.3 at ∼1 Mpc for the WL comparison and (b) ≈ 0.25 for the SaWLens comparison. The enclosed gas mass profiles from both Chandra and XMM rise to a value ≈1/8 times the total-mass profiles inferred from lensing at ≈0.5 Mpc and remain constant outside of that radius, suggesting that M {sub gas} × 8 profiles may be an excellent proxy for total-mass profiles at ≳ 0.5 Mpc in massive galaxy clusters.« less

  13. Imaging Basin Structure with Teleseismic Virtual Source Reflection Profiles

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Sheehan, A. F.; Yeck, W. L.; Miller, K. C.; Worthington, L. L.; Erslev, E.; Harder, S. H.; Anderson, M. L.; Siddoway, C. S.

    2011-12-01

    We demonstrate a case of using teleseisms recorded on single channel high frequency geophones to image upper crustal structure across the Bighorn Arch in north-central Wyoming. The dataset was obtained through the EarthScope FlexArray Bighorn Arch Seismic Experiment (BASE). In addition to traditional active and passive source seismic data acquisition, BASE included a 12 day continuous (passive source) deployment of 850 geophones with 'Texan' dataloggers. The geophones were deployed in three E-W lines in north-central Wyoming extending from the Powder River Basin across the Bighorn Mountains and across the Bighorn Basin, and two N-S lines on east and west flanks of the Bighorn Mountains. The station interval is roughly 1.5-2 km, good for imaging coherent shallow structures. The approach used in this study uses the surface reflection as virtual seismic source and reverberated teleseismic P-wave phase (PpPdp) (teleseismic P-wave reflected at receiver side free surface and then reflected off crustal seismic interface) to construct seismic profiles. These profiles are equivalent to conventional active source seismic reflection profiles except that high-frequency (up to 2.4 Hz) transmitted wave fields from distant earthquakes are used as sources. On the constructed seismic profiles, the coherent PpPdp phases beneath Powder River and Bighorn Basins are distinct after the source wavelet is removed from the seismograms by deconvolution. Under the Bighorn Arch, no clear coherent signals are observed. We combine phases PpPdp and Ps to constrain the averaged Vp/Vs: 2.05-2.15 for the Powder River Basin and 1.9-2.0 for the Bighorn Basin. These high Vp/Vs ratios suggest that the layers within which P-wave reverberates are sedimentary. Assuming Vp as 4 km/s under the Powder River Basin, the estimated thickness of sedimentary layer above reflection below the profile is 3-4.5 km, consistent with the depth of the top of the Tensleep Fm. Therefore we interpret the coherent PpPdp phases about 1-3 s after direct P-wave arrival as the reflections off the interface between the Paleozoic carbonates/sandstones and Mesozoic shales.

  14. Temperature profile determination in an absorbing plasma.

    NASA Technical Reports Server (NTRS)

    Usher, J. L.; Campbell, H. D.

    1972-01-01

    A new method has been developed to determine the temperature profile of an optically-non-thin plasma. The technique is essentially an extension of the brightness-emissivity method to the case of a cylindrically-symmetric plasma.

  15. Effects of low central fuelling on density and ion temperature profiles in reversed shear plasmas on JT-60U

    NASA Astrophysics Data System (ADS)

    Takenaga, H.; Ide, S.; Sakamoto, Y.; Fujita, T.; JT-60 Team

    2008-07-01

    Effects of low central fuelling on density and ion temperature profiles have been investigated using negative ion based neutral beam injection and electron cyclotron heating (ECH) in reversed shear plasmas on JT-60U. Strong internal transport barrier (ITB) was maintained in density and ion temperature profiles, when central fuelling was decreased by switching positive ion based neutral beam injection to ECH after the strong ITB formation. Similar density and ion temperature ITBs were formed for the low and high central fuelling cases during the plasma current ramp-up phase. Strong correlation between the density gradient and the ion temperature gradient was observed, indicating that particle transport and ion thermal transport are strongly coupled or the density gradient assists the ion temperature ITB formation through suppression of drift wave instabilities such as ion temperature gradient mode. These results support that the density and ion temperature ITBs can be formed under reactor relevant conditions.

  16. A simple method to incorporate water vapor absorption in the 15 microns remote temperature sounding

    NASA Technical Reports Server (NTRS)

    Dallu, G.; Prabhakara, C.; Conhath, B. J.

    1975-01-01

    The water vapor absorption in the 15 micron CO2 band, which can affect the remotely sensed temperatures near the surface, are estimated with the help of an empirical method. This method is based on the differential absorption properties of the water vapor in the 11-13 micron window region and does not require a detailed knowledge of the water vapor profile. With this approach Nimbus 4 IRIS radiance measurements are inverted to obtain temperature profiles. These calculated profiles agree with radiosonde data within about 2 C.

  17. Altitude profiles of temperature from 4 to 80 km over the tropics from MST radar and lidar

    NASA Astrophysics Data System (ADS)

    Parameswaran, K.; Sasi, M. N.; Ramkumar, G.; Nair, P. R.; Deepa, V.; Murthy, B. V. K.; Nayar, S. R. P.; Revathy, K.; Mrudula, G.; Satheesan, K.; Bhavanikumar, Y.; Sivakumar, V.; Raghunath, K.; Rajendraprasad, T.; Krishnaiah, M.

    2000-10-01

    Using ground-based techniques of MST radar and Lidar, temperature profiles in the entire height range of 4 to 75km are obtained for the first time at a tropical location. The temporal resolution of the profiles is ~1h in the lower altitudes and 12.5min in the higher altitudes and altitude resolution is ~300m. The errors involved in the derived values are presented. Preliminary analysis of temperature variations in a night revealed fluctuations with characteristics resembling those of large-scale gravity waves.

  18. Lateral Temperature-Gradient Method for High-Throughput Characterization of Material Processing by Millisecond Laser Annealing.

    PubMed

    Bell, Robert T; Jacobs, Alan G; Sorg, Victoria C; Jung, Byungki; Hill, Megan O; Treml, Benjamin E; Thompson, Michael O

    2016-09-12

    A high-throughput method for characterizing the temperature dependence of material properties following microsecond to millisecond thermal annealing, exploiting the temperature gradients created by a lateral gradient laser spike anneal (lgLSA), is presented. Laser scans generate spatial thermal gradients of up to 5 °C/μm with peak temperatures ranging from ambient to in excess of 1400 °C, limited only by laser power and materials thermal limits. Discrete spatial property measurements across the temperature gradient are then equivalent to independent measurements after varying temperature anneals. Accurate temperature calibrations, essential to quantitative analysis, are critical and methods for both peak temperature and spatial/temporal temperature profile characterization are presented. These include absolute temperature calibrations based on melting and thermal decomposition, and time-resolved profiles measured using platinum thermistors. A variety of spatially resolved measurement probes, ranging from point-like continuous profiling to large area sampling, are discussed. Examples from annealing of III-V semiconductors, CdSe quantum dots, low-κ dielectrics, and block copolymers are included to demonstrate the flexibility, high throughput, and precision of this technique.

  19. Kinetic simulations of the stability of a plasma confined by the magnetic field of a current rod

    NASA Astrophysics Data System (ADS)

    Tonge, J.; Leboeuf, J. N.; Huang, C.; Dawson, J. M.

    2003-09-01

    The kinetic stability of a plasma in the magnetic field of a current rod is investigated for various temperature and density profiles using three-dimensional particle-in-cell simulations. Such a plasma obeys similar physics to a plasma in a dipole magnetic field, while it is easier to perform computer simulations, and do theoretical analysis, of a plasma in the field of a current rod. Simple energy principle calculations and simulations with a variety of temperature and density profiles show that the plasma is stable to interchange for pressure profiles proportional to r-10/3. As predicted by theory the simulations also show that the density profile will be stationary as long as density is proportional to r-2 even though the temperature profile may not be stable.

  20. Ground-Water Temperature Data, Nevada Test Site and Vicinity, Nye, Clark, and Lincoln Counties, Nevada, 2000-2006

    USGS Publications Warehouse

    Reiner, Steven R.

    2007-01-01

    Ground-water temperature data were collected by the U.S. Geological Survey in wells at and in the vicinity of the Nevada Test Site during the years 2000-2006. Periodic ground-water temperatures were collected in 166 wells. In general, periodic ground-water temperatures were measured annually in each well at 5 and 55 feet below the water surface. Ground-water temperature profiles were collected in 73 wells. Temperatures were measured at multiple depths below the water surface to produce these profiles. Databases were constructed to present the ground-water temperature data.

  1. Ground-Water Temperature Data, Nevada Test Site and Vicinity, Nye, Clark, and Lincoln Counties, Nevada, 2000-2006.

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

    Steven R. Reiner

    2007-08-07

    Ground-water temperature data were collected by the U.S. Geological Survey in wells at and in the vicinity of the Nevada Test Site during the years 2000–2006. Periodic ground-water temperatures were collected in 166 wells. In general, periodic ground-water temperatures were measured annually in each well at 5 and 55 feet below the water surface. Ground-water temperature profiles were collected in 73 wells. Temperatures were measured at multiple depths below the water surface to produce these profiles. Databases were constructed to present the ground-water temperature data.

  2. Application of the Virtual Fields Method to a relaxation behaviour of rubbers

    NASA Astrophysics Data System (ADS)

    Yoon, Sung-ho; Siviour, Clive R.

    2018-07-01

    This paper presents the application of the Virtual Fields Method (VFM) for the characterization of viscoelastic behaviour of rubbers. The relaxation behaviour of the rubbers following a dynamic loading event is characterized using the dynamic VFM in which full-field (two dimensional) strain and acceleration data, obtained from high-speed imaging, are analysed by the principle of virtual work without traction force data, instead using the acceleration fields in the specimen to provide stress information. Two (silicone and nitrile) rubbers were tested in tension using a drop-weight apparatus. It is assumed that the dynamic behaviour is described by the combination of hyperelastic and Prony series models. A VFM based procedure is designed and used to produce the identification of the modulus term of a hyperelastic model and the Prony series parameters within a time scale determined by two experimental factors: imaging speed and loading duration. Then, the time range of the data is extended using experiments at different temperatures combined with the time-temperature superposition principle. Prior to these experimental analyses, finite element simulations were performed to validate the application of the proposed VFM analysis. Therefore, for the first time, it has been possible to identify relaxation behaviour of a material following dynamic loading, using a technique that can be applied to both small and large deformations.

  3. A search for thermal excursions from ancient extraterrestrial impacts using Hadean zircon Ti-U-Th-Pb depth profiles

    PubMed Central

    Abbott, Sunshine S.; Harrison, T. Mark; Schmitt, Axel K.; Mojzsis, Stephen J.

    2012-01-01

    Few terrestrial localities preserve more than a trace lithic record prior to ca. 3.8 Ga greatly limiting our understanding of the first 700 Ma of Earth history, a period inferred to have included a spike in the bolide flux to the inner solar system at ca. 3.85–3.95 Ga (the Late Heavy Bombardment, LHB). An accessible record of this era may be found in Hadean detrital zircons from the Jack Hills, Western Australia, in the form of μm-scale epitaxial overgrowths. By comparing crystallization temperatures of pre-3.8 Ga zircon overgrowths to the archive of zircon temperature spectra, it should, in principle, be possible to identify a distinctive impact signature. We have developed Ti-U-Th-Pb ion microprobe depth profiling to obtain age and temperature information within these zircon overgrowths and undertaken a feasibility study of its possible use in identifying impact events. Of eight grains profiled in this fashion, four have overgrowths of LHB-era age. Age vs. temperature profiles reveal a period between ca. 3.85–3.95 Ga (i.e., LHB era) characterized by significantly higher temperatures (approximately 840–875 °C) than do older or younger zircons or zircon domains (approximately 630–750 °C). However, temperatures approaching 900 °C can result in Pb isotopic exchange rendering interpretation of these profiles nonunique. Coupled age-temperature depth profiling shows promise in this role, and the preliminary data we report could represent the first terrestrial evidence for impact-related heating during the LHB. PMID:22869711

  4. Two-dimensional temperature and carbon dioxide concentration profiles in atmospheric laminar diffusion flames measured by mid-infrared direct absorption spectroscopy at 4.2 μm

    NASA Astrophysics Data System (ADS)

    Liu, Xunchen; Zhang, Guoyong; Huang, Yan; Wang, Yizun; Qi, Fei

    2018-04-01

    We present a multi-line flame thermometry technique based on mid-infrared direct absorption spectroscopy of carbon dioxide at its v_3 fundamental around 4.2 μm that is particularly suitable for sooting flames. Temperature and concentration profiles of gas phase molecules in a flame are important characteristics to understand its flame structure and combustion chemistry. One of the standard laboratory flames to analyze polycyclic aromatic hydrocarbons (PAH) and soot formation is laminar non-premixed co-flow flame, but PAH and soot introduce artifact to most non-contact optical measurements. Here we report an accurate diagnostic method of the temperature and concentration profiles of CO2 in ethylene diffusion flames by measuring its v_3 vibrational fundamental. An interband cascade laser was used to probe the R-branch bandhead at 4.2 μm, which is highly sensitive to temperature change, free from soot interference and ambient background. Calibration measurement was carried out both in a low-pressure Herriott cell and an atmospheric pressure tube furnace up to 1550 K to obtain spectroscopic parameters for high-temperature spectra. In our co-flow flame measurement, two-dimensional line-of-sight optical depth of an ethylene/N2 laminar sooting flame was recorded by dual-beam absorption scheme. The axially symmetrical attenuation coefficient profile of CO2 in the co-flow flame was reconstructed from the optical depth by Abel inversion. Spatially resolved flame temperature and in situ CO2 volume fraction profiles were derived from the calibrated CO2 spectroscopic parameters and compared with temperature profiles measured by two-line atomic fluorescence.

  5. Monitoring and Control Interface Based on Virtual Sensors

    PubMed Central

    Escobar, Ricardo F.; Adam-Medina, Manuel; García-Beltrán, Carlos D.; Olivares-Peregrino, Víctor H.; Juárez-Romero, David; Guerrero-Ramírez, Gerardo V.

    2014-01-01

    In this article, a toolbox based on a monitoring and control interface (MCI) is presented and applied in a heat exchanger. The MCI was programed in order to realize sensor fault detection and isolation and fault tolerance using virtual sensors. The virtual sensors were designed from model-based high-gain observers. To develop the control task, different kinds of control laws were included in the monitoring and control interface. These control laws are PID, MPC and a non-linear model-based control law. The MCI helps to maintain the heat exchanger under operation, even if a temperature outlet sensor fault occurs; in the case of outlet temperature sensor failure, the MCI will display an alarm. The monitoring and control interface is used as a practical tool to support electronic engineering students with heat transfer and control concepts to be applied in a double-pipe heat exchanger pilot plant. The method aims to teach the students through the observation and manipulation of the main variables of the process and by the interaction with the monitoring and control interface (MCI) developed in LabVIEW©. The MCI provides the electronic engineering students with the knowledge of heat exchanger behavior, since the interface is provided with a thermodynamic model that approximates the temperatures and the physical properties of the fluid (density and heat capacity). An advantage of the interface is the easy manipulation of the actuator for an automatic or manual operation. Another advantage of the monitoring and control interface is that all algorithms can be manipulated and modified by the users. PMID:25365462

  6. Extending the validation of multi-mode model for anomalous transport to high beta poloidal tokamak scenario in DIII-D

    NASA Astrophysics Data System (ADS)

    Pankin, A. Y.; Kritz, A. H.; Rafiq, T.; Garofalo, A. M.; Holod, I.; Weiland, J.

    2018-05-01

    The Multi-Mode Model (MMM7.1) for anomalous transport is tested in predictive modeling of temperature profiles of a high beta poloidal DIII-D discharge. This new H-mode plasma regime, with high beta poloidal and high bootstrap currents, has been studied in DIII-D tokamak discharges [A. Garofalo et al., Nucl. Fusion 55, 123025 (2015)]. The role of instabilities that can drive the anomalous transport described by MMM7.1 is investigated. The temperature profiles for a high beta poloidal DIII-D discharge are computed using the NCLASS model for the neoclassical transport and the Weiland and Electron Temperature Gradient (ETG) components of the MMM7.1 model for the anomalous transport. The neoclassical transport is found to be the main contributor to the ion thermal transport in the plasma core. The contributions from the ion temperature gradient driven modes are found to be important only outside of the internal transport barrier. The magnitudes of the predicted temperature profiles are found to be in a reasonable agreement with experimental profiles. The simulation results approximately reproduce the internal transport barrier in the ion temperature profile but not in the electron temperature profile due to a weak dependence of the ETG driven transport on the Shafranov shift in the ETG component of MMM7.1. Possible effects that can contribute to stabilization of these modes, for example, effects associated with the large beta poloidal such as the Shafranov shift stabilization in the MMM7.1 model, are discussed. It is demonstrated that the E × B flow shear has a relatively small effect in the formation of the internal transport barrier in the high beta poloidal DIII-D discharge 154406. The Shafranov shift (alpha stabilization) and small or reversed magnetic shear profiles are found to be the primary reasons for quenched anomalous transport in this discharge.

  7. Surface reflectance drives nest box temperature profiles and thermal suitability for target wildlife.

    PubMed

    Griffiths, Stephen R; Rowland, Jessica A; Briscoe, Natalie J; Lentini, Pia E; Handasyde, Kathrine A; Lumsden, Linda F; Robert, Kylie A

    2017-01-01

    Thermal properties of tree hollows play a major role in survival and reproduction of hollow-dependent fauna. Artificial hollows (nest boxes) are increasingly being used to supplement the loss of natural hollows; however, the factors that drive nest box thermal profiles have received surprisingly little attention. We investigated how differences in surface reflectance influenced temperature profiles of nest boxes painted three different colors (dark-green, light-green, and white: total solar reflectance 5.9%, 64.4%, and 90.3% respectively) using boxes designed for three groups of mammals: insectivorous bats, marsupial gliders and brushtail possums. Across the three different box designs, dark-green (low reflectance) boxes experienced the highest average and maximum daytime temperatures, had the greatest magnitude of variation in daytime temperatures within the box, and were consistently substantially warmer than light-green boxes (medium reflectance), white boxes (high reflectance), and ambient air temperatures. Results from biophysical model simulations demonstrated that variation in diurnal temperature profiles generated by painting boxes either high or low reflectance colors could have significant ecophysiological consequences for animals occupying boxes, with animals in dark-green boxes at high risk of acute heat-stress and dehydration during extreme heat events. Conversely in cold weather, our modelling indicated that there are higher cumulative energy costs for mammals, particularly smaller animals, occupying light-green boxes. Given their widespread use as a conservation tool, we suggest that before boxes are installed, consideration should be given to the effect of color on nest box temperature profiles, and the resultant thermal suitability of boxes for wildlife, particularly during extremes in weather. Managers of nest box programs should consider using several different colors and installing boxes across a range of both orientations and shade profiles (i.e., levels of canopy cover), to ensure target animals have access to artificial hollows with a broad range of thermal profiles, and can therefore choose boxes with optimal thermal conditions across different seasons.

  8. Surface reflectance drives nest box temperature profiles and thermal suitability for target wildlife

    PubMed Central

    Rowland, Jessica A.; Briscoe, Natalie J.; Lentini, Pia E.; Handasyde, Kathrine A.; Lumsden, Linda F.; Robert, Kylie A.

    2017-01-01

    Thermal properties of tree hollows play a major role in survival and reproduction of hollow-dependent fauna. Artificial hollows (nest boxes) are increasingly being used to supplement the loss of natural hollows; however, the factors that drive nest box thermal profiles have received surprisingly little attention. We investigated how differences in surface reflectance influenced temperature profiles of nest boxes painted three different colors (dark-green, light-green, and white: total solar reflectance 5.9%, 64.4%, and 90.3% respectively) using boxes designed for three groups of mammals: insectivorous bats, marsupial gliders and brushtail possums. Across the three different box designs, dark-green (low reflectance) boxes experienced the highest average and maximum daytime temperatures, had the greatest magnitude of variation in daytime temperatures within the box, and were consistently substantially warmer than light-green boxes (medium reflectance), white boxes (high reflectance), and ambient air temperatures. Results from biophysical model simulations demonstrated that variation in diurnal temperature profiles generated by painting boxes either high or low reflectance colors could have significant ecophysiological consequences for animals occupying boxes, with animals in dark-green boxes at high risk of acute heat-stress and dehydration during extreme heat events. Conversely in cold weather, our modelling indicated that there are higher cumulative energy costs for mammals, particularly smaller animals, occupying light-green boxes. Given their widespread use as a conservation tool, we suggest that before boxes are installed, consideration should be given to the effect of color on nest box temperature profiles, and the resultant thermal suitability of boxes for wildlife, particularly during extremes in weather. Managers of nest box programs should consider using several different colors and installing boxes across a range of both orientations and shade profiles (i.e., levels of canopy cover), to ensure target animals have access to artificial hollows with a broad range of thermal profiles, and can therefore choose boxes with optimal thermal conditions across different seasons. PMID:28472147

  9. Insight into small RNA abundance and expression in high- and low-temperature stress response using deep sequencing in Arabidopsis.

    PubMed

    Baev, Vesselin; Milev, Ivan; Naydenov, Mladen; Vachev, Tihomir; Apostolova, Elena; Mehterov, Nikolay; Gozmanva, Mariyana; Minkov, Georgi; Sablok, Gaurav; Yahubyan, Galina

    2014-11-01

    Small RNA profiling and assessing its dependence on changing environmental factors have expanded our understanding of the transcriptional and post-transcriptional regulation of plant stress responses. Insufficient data have been documented earlier to depict the profiling of small RNA classes in temperature-associated stress which has a wide implication for climate change biology. In the present study, we report a comparative assessment of the genome-wide profiling of small RNAs in Arabidopsis thaliana using two conditional responses, induced by high- and low-temperature. Genome-wide profiling of small RNAs revealed an abundance of 21 nt small RNAs at low temperature, while high temperature showed an abundance of 21 nt and 24 nt small RNAs. The two temperature treatments altered the expression of a specific subset of mature miRNAs and displayed differential expression of a number of miRNA isoforms (isomiRs). Comparative analysis demonstrated that a large number of protein-coding genes can give rise to differentially expressed small RNAs following temperature shifts. Low temperature caused accumulation of small RNAs, corresponding to the sense strand of a number of cold-responsive genes. In contrast, high temperature stimulated the production of small RNAs of both polarities from genes encoding functionally diverse proteins. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  10. The effect of heat generation on mixed convection flow in nano fluids over a horizontal circular cylinder

    NASA Astrophysics Data System (ADS)

    Juliyanto, Bagus; Widodo, Basuki; Imron, Chairul

    2018-04-01

    The purpose of this research is to study the effect of heat generation on mixed convection flow on Nano fluids over a horizontal circular cylinder of a heated in two dimension form. A stream of fluids are steady and incompressible, a stream flowing vertically upwards for circular cylinder and the boundary layer at the stagnation point. Three different types of nanoparticles considered are Cu, Al2O3, and TiO2. Mixed convection flow in Nano fluids on the surface of a circular cylinder will cause the boundary layer. The governing boundary layer equations are transformed into a non-dimensional form, and then the non-dimensional forms are transformed into a similar boundary equations by using stream function. Furthermore, an implicit finite-difference scheme known as the Keller-box method is applied to solve numerically the resulting similar boundary layer equations. The result of the research by varying the non-dimensional parameters are mixed convection, Prandtl number, nanoparticle volume fraction, heat generation, and radius of a cylinder are as follows. First, the velocity profile increase and temperature profile decrease when mixed convection parameter increase. Second, the velocity and temperature profiles decrease when Prandtl number parameter increase. Third, the velocity profile with the variation of nanoparticle volume fraction (χ) is increased when the value of χ is 0,1 ≤ χ ≤ 0,15 and the velocity profile decreases when the value of χ is 0,19 ≤ χ ≤ 0,5 while the temperature profile is increasing when the value of χ is 0,1 ≤ χ ≤ 0,5. Fourth, the velocity and temperature profiles increase when heat generation and the radius of the cylinder increase. The last, Cu, Al 2 O 3, and TiO 2 nanoparticles produce the same velocity and temperature profiles, but the three types of nanoparticles are different at the velocity and temperature values.

  11. Iodine-filter-based high spectral resolution lidar for atmospheric temperature measurements.

    PubMed

    Liu, Zhi-Shen; Bi, De-Cang; Song, Xiao-Quan; Xia, Jin-Bao; Li, Rong-Zhong; Wang, Zhang-Jun; She, Chiao-Yao

    2009-09-15

    This paper presents a method for measuring atmosphere temperature profile using a single iodine filter as frequency discriminator. This high spectral resolution lidar (HSRL) is a system reconfigured with the transmitter of a mobile Doppler wind lidar and with a receiving subsystem redesigned to pass the backscattering optical signal through the iodine cell twice to filter out the aerosol scattering signal and to allow analysis of the molecular scattering spectrum, thus measuring temperatures. We report what are believed to be the first results of vertical temperature profiling from the ground to 16 km altitude by this lidar system (power-aperture product=0.35 Wm(2)). Concurrent observations of an L band radiosonde were carried out on June 14 and August 3, 2008, in good agreement with HSRL temperature profiles.

  12. Master of Puppets: An Animation-by-Demonstration Computer Puppetry Authoring Framework

    NASA Astrophysics Data System (ADS)

    Cui, Yaoyuan; Mousas, Christos

    2018-03-01

    This paper presents Master of Puppets (MOP), an animation-by-demonstration framework that allows users to control the motion of virtual characters (puppets) in real time. In the first step, the user is asked to perform the necessary actions that correspond to the character's motions. The user's actions are recorded, and a hidden Markov model is used to learn the temporal profile of the actions. During the runtime of the framework, the user controls the motions of the virtual character based on the specified activities. The advantage of the MOP framework is that it recognizes and follows the progress of the user's actions in real time. Based on the forward algorithm, the method predicts the evolution of the user's actions, which corresponds to the evolution of the character's motion. This method treats characters as puppets that can perform only one motion at a time. This means that combinations of motion segments (motion synthesis), as well as the interpolation of individual motion sequences, are not provided as functionalities. By implementing the framework and presenting several computer puppetry scenarios, its efficiency and flexibility in animating virtual characters is demonstrated.

  13. Pharmacophore Models and Pharmacophore-Based Virtual Screening: Concepts and Applications Exemplified on Hydroxysteroid Dehydrogenases.

    PubMed

    Kaserer, Teresa; Beck, Katharina R; Akram, Muhammad; Odermatt, Alex; Schuster, Daniela

    2015-12-19

    Computational methods are well-established tools in the drug discovery process and can be employed for a variety of tasks. Common applications include lead identification and scaffold hopping, as well as lead optimization by structure-activity relationship analysis and selectivity profiling. In addition, compound-target interactions associated with potentially harmful effects can be identified and investigated. This review focuses on pharmacophore-based virtual screening campaigns specifically addressing the target class of hydroxysteroid dehydrogenases. Many members of this enzyme family are associated with specific pathological conditions, and pharmacological modulation of their activity may represent promising therapeutic strategies. On the other hand, unintended interference with their biological functions, e.g., upon inhibition by xenobiotics, can disrupt steroid hormone-mediated effects, thereby contributing to the development and progression of major diseases. Besides a general introduction to pharmacophore modeling and pharmacophore-based virtual screening, exemplary case studies from the field of short-chain dehydrogenase/reductase (SDR) research are presented. These success stories highlight the suitability of pharmacophore modeling for the various application fields and suggest its application also in futures studies.

  14. Assessment of virtual towers performed with scanning wind lidars and Ka-band radars during the XPIA experiment

    DOE PAGES

    Debnath, Mithu; Iungo, Giacomo Valerio; Brewer, W. Alan; ...

    2017-03-29

    During the eXperimental Planetary boundary layer Instrumentation Assessment (XPIA) campaign, which was carried out at the Boulder Atmospheric Observatory (BAO) in spring 2015, multiple-Doppler scanning strategies were carried out with scanning wind lidars and Ka-band radars. Specifically, step–stare measurements were collected simultaneously with three scanning Doppler lidars, while two scanning Ka-band radars carried out simultaneous range height indicator (RHI) scans. The XPIA experiment provided the unique opportunity to compare directly virtual-tower measurements performed simultaneously with Ka-band radars and Doppler wind lidars. Furthermore, multiple-Doppler measurements were assessed against sonic anemometer data acquired from the meteorological tower (met-tower) present at the BAOmore » site and a lidar wind profiler. As a result, this survey shows that – despite the different technologies, measurement volumes and sampling periods used for the lidar and radar measurements – a very good accuracy is achieved for both remote-sensing techniques for probing horizontal wind speed and wind direction with the virtual-tower scanning technique.« less

  15. Virtual Combinatorial Library Design, Synthesis and In vitro Anticancer Assessment of -2-Amino-3-Cyanopyridine Derivatives.

    PubMed

    Dev, Sanal; Dhaneshwar, Sunil R; Mathew, Bijo

    2018-01-01

    For the development of new class of anticancer agents, a series of novel 2-amino-3-cyanopyridine derivatives were designed from virtual screening with Glide program by setting Topoisomerase II as the target. The top ranked ten molecules from the virtual screening were synthesized by microwave assisted technique and investigated for their cytotoxic activity against MCF-7 and A- 549 cell lines by using sulforhodamine B assay method. The most active compound 2-amino-4-(3,5-dibromo-4-hydroxyphenyl)-6-(2,4- dichlorophenyl) nicotinonitrile (CG-5) showed significant cytotoxic profile with (LC50 = 97.1, TGI = 29.9 and GI50 = <0.1 µM) in MCF-7 and (LC50= 93.0, TGI= 50.0 and GI50= <7 µM) in A-549 cell lines. A molecular docking study was performed to explore the binding interaction of CG-5with the active site of Topoisomerase II. It can be concluded that halogen substituent pyridine ring was benefit for cytotoxicity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. River Inflows into Lakes: Basin Temperature Profiles Driven By Peeling Detrainment from Dense Underflows

    NASA Astrophysics Data System (ADS)

    Hogg, C. A. R.; Huppert, H. E.; Imberger, J.; Dalziel, S. B.

    2014-12-01

    Dense gravity currents from river inflows feed fluid into confined basins in lakes. Large inflows can influence temperature profiles in the basins. Existing parameterisations of the circulation and mixing of such inflows are often based on the entrainment of ambient fluid into the underflowing gravity currents. However, recent observations have suggested that uni-directional entrainment into a gravity current does not fully describe the transfer between such gravity currents and the ambient water. Laboratory experiments visualised peeling detrainment from the gravity current occurring when the ambient fluid was stratified. A theoretical model of the observed peeling detrainment was developed to predict the temperature profile in the basin. This new model gives a better approximation of the temperature profile observed in the experiments than the pre-existing entraining model. The model can now be developed such that it integrates into operational models of lake basins.

  17. Thermal structure of the Martian atmosphere retrieved from the IR spectrometry in the 15 μm CO2 band: input to MIRA

    NASA Astrophysics Data System (ADS)

    Zasova, L. V.; Formisano, V.; Grassi, D.; Igantiev, N. I.; Moroz, V. I.

    This paper describes one of the sources of the data concerning the thermal structure of the Martian atmosphere, based on the thermal IR spectrometry method. It allows to investigate the Martian atmosphere below 55 km by retrieving the temperature profiles from the 15 μm CO2 band. This approach enables to reach the vertical resolution of several kilometers and the temperature accuracy of several Kelvins. An aerosol abundance, which influences the temperature profile, is obtained from the continuum of the same spectrum parallel with the temperature profile and is taken into account in the temperature retrieval procedure in a self consistent way. Although this method has the limited vertical resolution, it possesses a significant advantage: the thermal IR spectrometry allows to monitor the temperature profiles with a good coverage both in space and local time. The Planetary Fourier spectrometer on board of Mars Express has the spectral range from 250 to 8000 cm-1 and a high spectral resolution of about 2 cm-1. Vertical temperature profiles retrieval is one of the main scientific goals of the experiment. The important data are expected to be obtained on the vertical thermal structure of the atmosphere, and its dependence on latitude, longitude, season, local time, clouds and dust loadings. These results should give a significant input in the future MIRA, being included in the Chapter “Structure of the atmosphere from the surface to 100 km”.

  18. Solid-solid phase transformation via internal stress-induced virtual melting, significantly below the melting temperature. Application to HMX energetic crystal.

    PubMed

    Levitas, Valery I; Henson, Bryan F; Smilowitz, Laura B; Asay, Blaine W

    2006-05-25

    We theoretically predict a new phenomenon, namely, that a solid-solid phase transformation (PT) with a large transformation strain can occur via internal stress-induced virtual melting along the interface at temperatures significantly (more than 100 K) below the melting temperature. We show that the energy of elastic stresses, induced by transformation strain, increases the driving force for melting and reduces the melting temperature. Immediately after melting, stresses relax and the unstable melt solidifies. Fast solidification in a thin layer leads to nanoscale cracking which does not affect the thermodynamics or kinetics of the solid-solid transformation. Thus, virtual melting represents a new mechanism of solid-solid PT, stress relaxation, and loss of coherence at a moving solid-solid interface. It also removes the athermal interface friction and deletes the thermomechanical memory of preceding cycles of the direct-reverse transformation. It is also found that nonhydrostatic compressive internal stresses promote melting in contrast to hydrostatic pressure. Sixteen theoretical predictions are in qualitative and quantitative agreement with experiments conducted on the PTs in the energetic crystal HMX. In particular, (a) the energy of internal stresses is sufficient to reduce the melting temperature from 551 to 430 K for the delta phase during the beta --> delta PT and from 520 to 400 K for the beta phase during the delta --> beta PT; (b) predicted activation energies for direct and reverse PTs coincide with corresponding melting energies of the beta and delta phases and with the experimental values; (c) the temperature dependence of the rate constant is determined by the heat of fusion, for both direct and reverse PTs; results b and c are obtained both for overall kinetics and for interface propagation; (d) considerable nanocracking, homogeneously distributed in the transformed material, accompanies the PT, as predicted by theory; (e) the nanocracking does not change the PT thermodynamics or kinetics appreciably for the first and the second PT beta <--> delta cycles, as predicted by theory; (f) beta <--> delta PTs start at a very small driving force (in contrast to all known solid-solid transformations with large transformation strain), that is, elastic energy and athermal interface friction must be negligible; (g) beta --> alpha and alpha --> beta PTs, which are thermodynamically possible in the temperature range 382.4 < theta < 430 K and below 382.4 K, respectively, do not occur.

  19. Should We Believe Atmospheric Temperatures Measured by Entry Accelerometers Traveling at "Slow" Near-Sonic Speeds?

    NASA Technical Reports Server (NTRS)

    Withers, Paul

    2005-01-01

    Mars Pathfinder's Accelerometer instrument measured an unexpected and large temperature inversion between 10 and 20 kilometer altitude. Other instruments have failed to detect similar temperature inversions. I test whether this inversion is real or not by examining what changes have to be made to the assumptions in the accelerometer data processing to obtain a more "expected" temperature profile. Changes in derived temperature of up to 30K, or 15%, are necessary, which correspond to changes in derived density of up to 25% and changes in derived pressure of up to 10%. If the drag coefficient is changed to satisfy this, then instead of decreasing from 1.6 to 1.4 from 20 kilometers to 10 kilometers, the drag coefficient must increase from 1.6 to 1.8 instead. If winds are invoked, then speeds of 60 meters per second are necessary, four times greater than those predicted. Refinements to the equation of hydrostatic equilibrium modify the temperature profile by an order of magnitude less than the desired amount. Unrealistically large instrument drifts of 0.5-1.0 meters per square second are needed to adjust the temperature profile as desired. However, rotational contributions to the accelerations may have the necessary magnitude and direction to make this correction. Determining whether this hypothesis is true will require further study of the rigid body equations of motion, with detailed knowledge of the positions of all six accelerometers. The paradox concerning this inversion is not yet resolved. It is important to resolve it because the paradox has some startling implications. At one extreme, are temperature profiles derived from accelerometers inherently inaccurate by 20K or more? At the other extreme, are RS temperature profiles inaccurate by this same amount?

  20. Bubble behavior in molten glass in a temperature gradient. [in reduced gravity rocket experiment

    NASA Technical Reports Server (NTRS)

    Meyyappan, M.; Subramanian, R. S.; Wilcox, W. R.; Smith, H.

    1982-01-01

    Gas bubble motion in a temperature gradient was observed in a sodium borate melt in a reduced gravity rocket experiment under the NASA SPAR program. Large bubbles tended to move faster than smaller ones, as predicted by theory. When the bubbles contacted a heated platinum strip, motion virtually ceased because the melt only imperfectly wets platinum. In some cases bubble diameter increased noticeably with time.

  1. Improving 7-Day Forecast Skill by Assimilation of Retrieved AIRS Temperature Profiles

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Rosenberg, Bob

    2016-01-01

    We conducted a new set of Data Assimilation Experiments covering the period January 1 to February 29, 2016 using the GEOS-5 DAS. Our experiments assimilate all data used operationally by GMAO (Control) with some modifications. Significant improvement in Global and Southern Hemisphere Extra-tropical 7-day forecast skill was obtained when: We assimilated AIRS Quality Controlled temperature profiles in place of observed AIRS radiances, and also did not assimilate CrISATMS radiances, nor did we assimilate radiosonde temperature profiles or aircraft temperatures. This new methodology did not improve or degrade 7-day Northern Hemispheric Extra-tropical forecast skill. We are conducting experiments aimed at further improving of Northern Hemisphere Extra-tropical forecast skill.

  2. Temperature profile detector

    DOEpatents

    Tokarz, Richard D.

    1983-01-01

    A temperature profile detector shown as a tubular enclosure surrounding an elongated electrical conductor having a plurality of meltable conductive segments surrounding it. Duplicative meltable segments are spaced apart from one another along the length of the enclosure. Electrical insulators surround these elements to confine molten material from the segments in bridging contact between the conductor and a second electrical conductor, which might be the confining tube. The location and rate of growth of the resulting short circuits between the two conductors can be monitored by measuring changes in electrical resistance between terminals at both ends of the two conductors. Additional conductors and separate sets of meltable segments operational at differing temperatures can be monitored simultaneously for measuring different temperature profiles.

  3. Wave Field Synthesis of moving sources with arbitrary trajectory and velocity profile.

    PubMed

    Firtha, Gergely; Fiala, Péter

    2017-08-01

    The sound field synthesis of moving sound sources is of great importance when dynamic virtual sound scenes are to be reconstructed. Previous solutions considered only virtual sources moving uniformly along a straight trajectory, synthesized employing a linear loudspeaker array. This article presents the synthesis of point sources following an arbitrary trajectory. Under high-frequency assumptions 2.5D Wave Field Synthesis driving functions are derived for arbitrary shaped secondary source contours by adapting the stationary phase approximation to the dynamic description of sources in motion. It is explained how a referencing function should be chosen in order to optimize the amplitude of synthesis on an arbitrary receiver curve. Finally, a finite difference implementation scheme is considered, making the presented approach suitable for real-time applications.

  4. An objective algorithm for reconstructing the three-dimensional ocean temperature field based on Argo profiles and SST data

    NASA Astrophysics Data System (ADS)

    Zhou, Chaojie; Ding, Xiaohua; Zhang, Jie; Yang, Jungang; Ma, Qiang

    2017-12-01

    While global oceanic surface information with large-scale, real-time, high-resolution data is collected by satellite remote sensing instrumentation, three-dimensional (3D) observations are usually obtained from in situ measurements, but with minimal coverage and spatial resolution. To meet the needs of 3D ocean investigations, we have developed a new algorithm to reconstruct the 3D ocean temperature field based on the Array for Real-time Geostrophic Oceanography (Argo) profiles and sea surface temperature (SST) data. The Argo temperature profiles are first optimally fitted to generate a series of temperature functions of depth, with the vertical temperature structure represented continuously. By calculating the derivatives of the fitted functions, the calculation of the vertical temperature gradient of the Argo profiles at an arbitrary depth is accomplished. A gridded 3D temperature gradient field is then found by applying inverse distance weighting interpolation in the horizontal direction. Combined with the processed SST, the 3D temperature field reconstruction is realized below the surface using the gridded temperature gradient. Finally, to confirm the effectiveness of the algorithm, an experiment in the Pacific Ocean south of Japan is conducted, for which a 3D temperature field is generated. Compared with other similar gridded products, the reconstructed 3D temperature field derived by the proposed algorithm achieves satisfactory accuracy, with correlation coefficients of 0.99 obtained, including a higher spatial resolution (0.25° × 0.25°), resulting in the capture of smaller-scale characteristics. Finally, both the accuracy and the superiority of the algorithm are validated.

  5. Pioneer 10 and 11 radio occultations by Jupiter. [atmospheric temperature structure

    NASA Technical Reports Server (NTRS)

    Kliore, A. J.; Woiceshyn, P. M.; Hubbard, W. B.

    1977-01-01

    Results on the temperature structure of the Jovian atmosphere are reviewed which were obtained by applying an integral inversion technique combined with a model for the planet's shape based on gravity data to Pioneer 10 and 11 radio-occultation data. The technique applied to obtain temperature profiles from the Pioneer data consisted of defining a center of refraction based on a computation of the radius of curvature in the plane of refraction and the normal direction to the equipotential surface at the closest approach point of a ray. Observations performed during the Pioneer 10 entry and exit and the Pioneer 11 exit are analyzed, sources of uncertainty are identified, and representative pressure-temperature profiles are presented which clearly show a temperature inversion between 10 and 100 mb. Effects of zonal winds on the reliability of radio-occultation temperature profiles are briefly discussed.

  6. Physical Retrieval of Surface Emissivity Spectrum from Hyperspectral Infrared Radiances

    NASA Technical Reports Server (NTRS)

    Li, Jun; Weisz, Elisabeth; Zhou, Daniel K.

    2007-01-01

    Retrieval of temperature, moisture profiles and surface skin temperature from hyperspectral infrared (IR) radiances requires spectral information about the surface emissivity. Using constant or inaccurate surface emissivities typically results in large retrieval errors, particularly over semi-arid or arid areas where the variation in emissivity spectrum is large both spectrally and spatially. In this study, a physically based algorithm has been developed to retrieve a hyperspectral IR emissivity spectrum simultaneously with the temperature and moisture profiles, as well as the surface skin temperature. To make the solution stable and efficient, the hyperspectral emissivity spectrum is represented by eigenvectors, derived from the laboratory measured hyperspectral emissivity database, in the retrieval process. Experience with AIRS (Atmospheric InfraRed Sounder) radiances shows that a simultaneous retrieval of the emissivity spectrum and the sounding improves the surface skin temperature as well as temperature and moisture profiles, particularly in the near surface layer.

  7. Prison Therapeutic Community Treatment for Female Offenders: Profiles and Preliminary Findings for Mental Health and Other Variables (Crime, Substance Use and HIV Risk)

    ERIC Educational Resources Information Center

    Sacks, Joann Y.; Sacks, Stanley; Mckendrick, Karen; Banks, Steven; Schoeneberger, Marlies; Hamilton, Zachary; Stommel, Joseph; Shoemaker, Joanie

    2008-01-01

    This random assignment study compared women in a prison Therapeutic Community (TC) program with those in a cognitive-behavioral intervention. Over two thirds of study subjects received a lifetime diagnosis of severe mental disorder, nearly one-half received a diagnosis of PTSD, and virtually all reported exposure to trauma. Preliminary analysis (n…

  8. A study of electron density profiles in relation to ionization sources and ground-based radio wave absorption measurements, part 1

    NASA Technical Reports Server (NTRS)

    Gnanalingam, S.; Kane, J. A.

    1973-01-01

    An extensive set of ground-based measurements of the diurnal variation of medium frequency radio wave adsorption and virtual height is analyzed in terms of current understanding of the D- and lower E-region ion production and loss process. When this is done a gross discrepancy arises, the source of which is not known.

  9. Analysis of Cloud-Based Database Systems

    DTIC Science & Technology

    2015-06-01

    EU) citizens under the Patriot Act [3]. Unforeseen virtualization bugs have caused wide-reaching outages [4], leaving customers helpless to assist...collected from SQL Server Profiler traces. We analyze the trace results captured from our test bed both before and after increasing system resources...cloud test- bed . A. DATA COLLECTION, PARSING, AND ORGANIZATION Once we finished collecting the trace data, we knew we needed to have as close a

  10. Proof-of-principle demonstration of a virtual flow meter-based transducer for gaseous helium monitoring in particle accelerator cryogenics

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

    Arpaia, P.; Technology Department, European Organization for Nuclear Research; Blanco, E.

    2015-07-15

    A transducer based on a virtual flow meter is proposed for monitoring helium distribution and consumption in cryogenic systems for particle accelerators. The virtual flow meter allows technical and economical constraints, preventing installation of physical instruments in all the needed measurement points, to be overcome. Virtual flow meter performance for the alternative models of Samson [ http://www.samson.de (2015)] and Sereg-Schlumberger [ http://www.slb.com/ (2015)] is compared with the standard IEC 60534-2-1 [Industrial-process control valves—Part 2-1: Flow capacity—sizing equations for fluid flow under installed conditions (2011), https://webstore.iec.ch/publication/2461], for a large temperature range, for both gaseous and liquid helium phases, and for differentmore » pressure drops. Then, the calibration function of the transducer is derived. Finally, the experimental validation for the helium gaseous state on the test station for superconducting magnets in the laboratory SM18 [Pirotte et al., AIP Conf. Proc. 1573, 187 (2014)] at CERN is reported.« less

  11. Data Assimilation Experiments Using Quality Controlled AIRS Version 5 Temperature Soundings

    NASA Technical Reports Server (NTRS)

    Susskind, Joel

    2009-01-01

    The AIRS Science Team Version 5 retrieval algorithm has been finalized and is now operational at the Goddard DAAC in the processing (and reprocessing) of all AIRS data. The AIRS Science Team Version 5 retrieval algorithm contains a number of significant improvements over Version 4. Two very significant improvements are described briefly below. 1) The AIRS Science Team Radiative Transfer Algorithm (RTA) has now been upgraded to accurately account for effects of non-local thermodynamic equilibrium on the AIRS observations. This allows for use of AIRS observations in the entire 4.3 micron CO2 absorption band in the retrieval algorithm during both day and night. Following theoretical considerations, tropospheric temperature profile information is obtained almost exclusively from clear column radiances in the 4.3 micron CO2 band in the AIRS Version 5 temperature profile retrieval step. These clear column radiances are a derived product that are indicative of radiances AIRS channels would have seen if the field of view were completely clear. Clear column radiances for all channels are determined using tropospheric sounding 15 micron CO2 observations. This approach allows for the generation of accurate values of clear column radiances and T(p) under most cloud conditions. 2) Another very significant improvement in Version 5 is the ability to generate accurate case-by-case, level-by-level error estimates for the atmospheric temperature profile, as well as for channel-by-channel clear column radiances. These error estimates are used for quality control of the retrieved products. Based on error estimate thresholds, each temperature profiles is assigned a characteristic pressure, pg, down to which the profile is characterized as good for use for data assimilation purposes. We have conducted forecast impact experiments assimilating AIRS quality controlled temperature profiles using the NASA GEOS-5 data assimilation system, consisting of the NCEP GSI analysis coupled with the NASA FVGCM, at a spatial resolution of 0.5 deg by 0.5 deg. Assimilation of Quality Controlled AIRS temperature profiles down to pg resulted in significantly improved forecast skill compared to that obtained from experiments when all data used operationally by NCEP, except for AIRS data, is assimilated. These forecasts were also significantly better than to those obtained when AIRS radiances (rather than temperature profiles) are assimilated, which is the way AIRS data is used operationally by NCEP and ECMWF.

  12. A new retrieval algorithm for tropospheric temperature, humidity and pressure profiling based on GNSS radio occultation data

    NASA Astrophysics Data System (ADS)

    Kirchengast, Gottfried; Li, Ying; Scherllin-Pirscher, Barbara; Schwärz, Marc; Schwarz, Jakob; Nielsen, Johannes K.

    2017-04-01

    The GNSS radio occultation (RO) technique is an important remote sensing technique for obtaining thermodynamic profiles of temperature, humidity, and pressure in the Earth's troposphere. However, due to refraction effects of both dry ambient air and water vapor in the troposphere, retrieval of accurate thermodynamic profiles at these lower altitudes is challenging and requires suitable background information in addition to the RO refractivity information. Here we introduce a new moist air retrieval algorithm aiming to improve the quality and robustness of retrieving temperature, humidity and pressure profiles in moist air tropospheric conditions. The new algorithm consists of four steps: (1) use of prescribed specific humidity and its uncertainty to retrieve temperature and its associated uncertainty; (2) use of prescribed temperature and its uncertainty to retrieve specific humidity and its associated uncertainty; (3) use of the previous results to estimate final temperature and specific humidity profiles through optimal estimation; (4) determination of air pressure and density profiles from the results obtained before. The new algorithm does not require elaborated matrix inversions which are otherwise widely used in 1D-Var retrieval algorithms, and it allows a transparent uncertainty propagation, whereby the uncertainties of prescribed variables are dynamically estimated accounting for their spatial and temporal variations. Estimated random uncertainties are calculated by constructing error covariance matrices from co-located ECMWF short-range forecast and corresponding analysis profiles. Systematic uncertainties are estimated by empirical modeling. The influence of regarding or disregarding vertical error correlations is quantified. The new scheme is implemented with static input uncertainty profiles in WEGC's current OPSv5.6 processing system and with full scope in WEGC's next-generation system, the Reference Occultation Processing System (rOPS). Results from both WEGC systems, current OPSv5.6 and next-generation rOPS, are shown and discussed, based on both insights from individual profiles and statistical ensembles, and compared to moist air retrieval results from the UCAR Boulder and ROM-SAF Copenhagen centers. The results show that the new algorithmic scheme improves the temperature, humidity and pressure retrieval performance, in particular also the robustness including for integrated uncertainty estimation for large-scale applications, over the previous algorithms. The new rOPS-implemented algorithm will therefore be used in the first large-scale reprocessing towards a tropospheric climate data record 2001-2016 by the rOPS, including its integrated uncertainty propagation.

  13. Virtual source reflection imaging of the Socorro Magma Body, New Mexico, using a dense seismic array

    NASA Astrophysics Data System (ADS)

    Finlay, T. S.; Worthington, L. L.; Schmandt, B.; Hansen, S. M.; Bilek, S. L.; Aster, R. C.; Ranasinghe, N. R.

    2017-12-01

    The Socorro Magma Body (SMB) is one of the largest known actively inflating continental magmatic intrusions. Previous studies have relied on sparse instrument coverage to determine its spatial extent, depth, and seismic signature, which characterized the body as a thin sill with a surface at 19 km below the Earth's surface. However, over the last two decades, InSAR and magneto-telluric (MT) studies have shed new light on the SMB and invigorated the scientific debate of the spatial distribution and uplift rate of the SMB. We return to seismic imaging of the SMB with the Sevilleta Array, a 12-day deployment of approximately 800 vertical component, 10-Hz geophones north of Socorro, New Mexico above and around the estimated northern half of the SMB. Teleseismic virtual source reflection profiling (TVR) employs the free surface reflection off of a teleseismic P as a virtual source in dense arrays, and has been used successfully to image basin structure and the Moho in multiple tectonic environments. The Sevilleta Array recorded 62 teleseismic events greater than M5. Applying TVR to the data collected by the Sevilleta Array, we present stacks from four events that produced the with high signal-to-noise ratios and simple source-time functions: the February 11, 2015 M6.7 in northern Argentina, the February 19, 2015 M5.4 in Kamchatka, Russia, and the February 21, 2015 M5.1 and February 22, 2015 M5.5 in western Colombia. Preliminary results suggest eastward-dipping reflectors at approximately 5 km depth near the Sierra Ladrones range in the northwestern corner of the array. Further analysis will focus on creating profiles across the area of maximum SMB uplift and constraining basin geometry.

  14. Testing and validation of multi-lidar scanning strategies for wind energy applications: Testing and validation of multi-lidar scanning strategies for wind energy applications

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

    Newman, Jennifer F.; Bonin, Timothy A.; Klein, Petra M.

    Several factors cause lidars to measure different values of turbulence than an anemometer on a tower, including volume averaging, instrument noise, and the use of a scanning circle to estimate the wind field. One way to avoid the use of a scanning circle is to deploy multiple scanning lidars and point them toward the same volume in space to collect velocity measurements and extract high-resolution turbulence information. This paper explores the use of two multi-lidar scanning strategies, the tri-Doppler technique and the virtual tower technique, for measuring 3-D turbulence. In Summer 2013, a vertically profiling Leosphere WindCube lidar and threemore » Halo Photonics Streamline lidars were operated at the Southern Great Plains Atmospheric Radiation Measurement site to test these multi-lidar scanning strategies. During the first half of the field campaign, all three scanning lidars were pointed at approximately the same point in space and a tri-Doppler analysis was completed to calculate the three-dimensional wind vector every second. Next, all three scanning lidars were used to build a “virtual tower” above the WindCube lidar. Results indicate that the tri-Doppler technique measures higher values of horizontal turbulence than the WindCube lidar under stable atmospheric conditions, reduces variance contamination under unstable conditions, and can measure highresolution profiles of mean wind speed and direction. The virtual tower technique provides adequate turbulence information under stable conditions but cannot capture the full temporal variability of turbulence experienced under unstable conditions because of the time needed to readjust the scans.« less

  15. Imaging Gravity Waves in Lower Stratospheric AMSU-A Radiances. Part 1: Simple Forward Model

    DTIC Science & Technology

    2006-08-14

    brightening” of microwave radiances acquired from purely vertical background temperature profiles by cross- track scanners. Waves propagating along track...three-dimensional wave fields. For example, some limb sensors return high- resolution vertical temperature profiles with wave oscilla- tions...provide only ver- tical profiles of wave oscillations, similar to radiosonde and rocketsonde data. Similarly, limb-tracking measurements from the

  16. Infrasonic ray tracing applied to mesoscale atmospheric structures: refraction by hurricanes.

    PubMed

    Bedard, Alfred J; Jones, R Michael

    2013-11-01

    A ray-tracing program is used to estimate the refraction of infrasound by the temperature structure of the atmosphere and by hurricanes represented by a Rankine-combined vortex wind plus a temperature perturbation. Refraction by the hurricane winds is significant, giving rise to regions of focusing, defocusing, and virtual sources. The refraction of infrasound by the temperature anomaly associated with a hurricane is small, probably no larger than that from uncertainties in the wind field. The results are pertinent to interpreting ocean wave generated infrasound in the vicinities of tropical cyclones.

  17. The use of the virtual reality as intervention tool in the postoperative of cardiac surgery.

    PubMed

    Cacau, Lucas de Assis Pereira; Oliveira, Géssica Uruga; Maynard, Luana Godinho; Araújo Filho, Amaro Afrânio de; Silva, Walderi Monteiro da; Cerqueria Neto, Manoel Luiz; Antoniolli, Angelo Roberto; Santana-Filho, Valter J

    2013-06-01

    Cardiac surgery has been the intervention of choice in many cases of cardiovascular diseases. Susceptibility to postoperative complications, cardiac rehabilitation is indicated. Therapeutic resources, such as virtual reality has been helping the rehabilitational process. The aim of the study was to evaluate the use of virtual reality in the functional rehabilitation of patients in the postoperative period. Patients were randomized into two groups, Virtual Reality (VRG, n = 30) and Control (CG, n = 30). The response to treatment was assessed through the functional independence measure (FIM), by the 6-minute walk test (6MWT) and the Nottingham Health Profile (NHP). Evaluations were performed preoperatively and postoperatively. On the first day after surgery, patients in both groups showed decreased functional performance. However, the VRG showed lower reduction (45.712.3) when compared to CG (35.0612.09, P<0.05) in first postoperative day, and no significant difference in performance on discharge day (P>0.05). In evaluating the NHP field, we observed a significant decrease in pain score at third assessment (P<0.05). These patients also had a higher energy level in the first evaluation (P<0.05). There were no differences with statistical significance for emotional reactions, physical ability, and social interaction. The length of stay was significantly shorter in patients of VRG (9.410.5 days vs. 12.2 1 0.9 days, P<0.05), which also had a higher 6MWD (319.9119.3 meters vs. 263.5115.4 meters, P<0.02). Adjunctive treatment with virtual reality demonstrated benefits, with better functional performance in patients undergoing cardiac surgery.

  18. Vertical profiles of ozone, carbon monoxide, and dew-point temperature obtained during GTE/CITE 1, October-November 1983. [Chemical Instrumentation Test and Evaluation

    NASA Technical Reports Server (NTRS)

    Fishman, Jack; Gregory, Gerald L.; Sachse, Glen W.; Beck, Sherwin M.; Hill, Gerald F.

    1987-01-01

    A set of 14 pairs of vertical profiles of ozone and carbon monoxide, obtained with fast-response instrumentation, is presented. Most of these profiles, which were measured in the remote troposphere, also have supporting fast-response dew-point temperature profiles. The data suggest that the continental boundary layer is a source of tropospheric ozone, even in October and November, when photochemical activity should be rather small. In general, the small-scale vertical variability between CO and O3 is in phase. At low latitudes this relationship defines levels in the atmosphere where midlatitude air is being transported to lower latitudes, since lower dew-point temperatures accompany these higher CO and O3 concentrations. A set of profiles which is suggestive of interhemispheric transport is also presented. Independent meteorological analyses support these interpretations.

  19. Laser-diagnostic mapping of temperature and soot statistics in a 2-m diameter turbulent pool fire

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

    Kearney, Sean P.; Grasser, Thomas W.

    We present spatial profiles of temperature and soot-volume-fraction statistics from a sooting 2-m base diameter turbulent pool fire, burning a 10%-toluene / 90%-methanol fuel mixture. Dual-pump coherent anti-Stokes Raman scattering and laser-induced incandescence are utilized to obtain radial profiles of temperature and soot probability density functions (pdf) as well as estimates of temperature/soot joint statistics at three vertical heights above the surface of the methanol/toluene fuel pool. Results are presented both in the fuel vapor-dome region at ¼ base diameter and in the actively burning region at ½ and ¾ diameters above the fuel surface. The spatial evolution of themore » soot and temperature pdfs is discussed and profiles of the temperature and soot mean and rms statistics are provided. Joint temperature/soot statistics are presented as spatially resolved conditional averages across the fire plume, and in terms of a joint pdf obtained by including measurements from multiple spatial locations.« less

  20. Laser-diagnostic mapping of temperature and soot statistics in a 2-m diameter turbulent pool fire

    DOE PAGES

    Kearney, Sean P.; Grasser, Thomas W.

    2017-08-10

    We present spatial profiles of temperature and soot-volume-fraction statistics from a sooting 2-m base diameter turbulent pool fire, burning a 10%-toluene / 90%-methanol fuel mixture. Dual-pump coherent anti-Stokes Raman scattering and laser-induced incandescence are utilized to obtain radial profiles of temperature and soot probability density functions (pdf) as well as estimates of temperature/soot joint statistics at three vertical heights above the surface of the methanol/toluene fuel pool. Results are presented both in the fuel vapor-dome region at ¼ base diameter and in the actively burning region at ½ and ¾ diameters above the fuel surface. The spatial evolution of themore » soot and temperature pdfs is discussed and profiles of the temperature and soot mean and rms statistics are provided. Joint temperature/soot statistics are presented as spatially resolved conditional averages across the fire plume, and in terms of a joint pdf obtained by including measurements from multiple spatial locations.« less

  1. Computational fluid dynamics modeling of bun baking process under different oven load conditions.

    PubMed

    Tank, A; Chhanwal, N; Indrani, D; Anandharamakrishnan, C

    2014-09-01

    A computational fluid dynamics (CFD) model was developed to study the temperature profile of the bun during baking process. Evaporation-condensation mechanism and effect of the latent heat during phase change of water was incorporated in this model to represent actual bun baking process. Simulation results were validated with experimental measurements of bun temperature at two different positions. Baking process is completed within 20 min, after the temperature of crumb become stable at 98 °C. Further, this study was extended to investigate the effect of partially (two baking trays) loaded and fully loaded (eight baking trays) oven on temperature profile of bun. Velocity and temperature profile differs in partially loaded and fully loaded oven. Bun placed in top rack showed rapid baking while bun placed in bottom rack showed slower baking due to uneven temperature distribution in the oven. Hence, placement of bun inside the oven affects temperature of bun and consequently, the quality of the product.

  2. Correlation study of actual temperature profile and in-line metrology measurements for within-wafer uniformity improvement and wafer edge yield enhancement (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Fang, Fang; Vaid, Alok; Vinslava, Alina; Casselberry, Richard; Mishra, Shailendra; Dixit, Dhairya; Timoney, Padraig; Chu, Dinh; Porter, Candice; Song, Da; Ren, Zhou

    2018-03-01

    It is getting more important to monitor all aspects of influencing parameters in critical etch steps and utilize them as tuning knobs for within-wafer uniformity improvement and wafer edge yield enhancement. Meanwhile, we took a dive in pursuing "measuring what matters" and challenged ourselves for more aspects of signals acquired in actual process conditions. Among these factors which are considered subtle previously, we identified Temperature, especially electrostatic chuck (ESC) Temperature measurement in real etch process conditions have direct correlation to in-line measurements. In this work, we used SensArray technique (EtchTemp-SE wafer) to measure ESC temperature profile on a 300mm wafer with plasma turning on to reproduce actual temperature pattern on wafers in real production process conditions. In field applications, we observed substantial correlation between ESC temperature and in-line optical metrology measurements and since temperature is a process factor that can be tuning through set-temperature modulations, we have identified process knobs with known impact on physical profile variations. Furthermore, ESC temperature profile on a 300mm wafer is configured as multiple zones upon radius and SensArray measurements mechanism could catch such zonal distribution as well, which enables detailed temperature modulations targeting edge ring only where most of chips can be harvested and critical zone for yield enhancement. Last but not least, compared with control reference (ESC Temperature in static plasma-off status), we also get additional factors to investigate in chamber-to-chamber matching study and make process tool fleet match on the basis really matters in production. KLA-Tencor EtchTemp-SE wafer enables Plasma On wafer temperature monitoring of silicon etch process. This wafer is wireless and has 65 sensors with measurement range from 20 to 140°C. the wafer is designed to run in real production recipe plasma on condition with maximum RF power up to 7KW. The wafer surface is coated with Yttrium oxide film which allows Silicon Etch chemistry. At Fab-8, we carried investigations in 14 nm FEOL critical etch process which has direct impact on yield, using SensorArray EtchTemp-SE wafer, we measured ESC temperature profile across multiple chambers, for both plasma on and plasma off, promising results achieved on chamber temperature signature identification, guideline for chamber to chamber matching improvement. Correlation between wafer mean temperature and determining criticality-process parameters of recess depth and CD is observed. Furthermore, detail zonal temperature/profile correlation is investigated to identify individual correlation in each chuck zone, and provided unique process knobs corresponding to each chunk. Meanwhile, passive ESC Chuck DOE was done to modulate wafer temperature at different zones, and Sensor Array wafer measurements verified temperature responding well with the ESC set point. Correlation R2 = 0.9979 for outer ring and R2 = 0.9981 for Mid Outer ring is observed, as shown in . Experiments planning to modulate edge zone ESC temperature to tune profile within-wafer uniformity and prove gain in edge yield enhancement and to improve edge yield is underway.

  3. Complete temperature profiles in ultra-high-pressure liquid chromatography columns.

    PubMed

    Gritti, Fabrice; Guiochon, Georges

    2008-07-01

    The temperature profiles were calculated along and across seven packed columns (lengths 30, 50, 100, and 150 mm, i.d., 1 and 2.1 mm, all packed with Acquity UPLC, BEH-C 18 particles, average d(p) approximately 1.7 microm) and their stainless steel tubes (o.d. 4.53 and 6.35 mm). These columns were kept horizontal and sheltered from forced air convection (i.e., under still air conditions), at room temperature. They were all percolated with pure acetonitrile, either under the maximum pressure drop (1034 bar) or at the maximum flow rate (2 mL/min) permitted by the chromatograph. The heat balance equation of chromatographic columns was discretized and solved numerically with minimum approximation. Both the compressibility and the thermal expansion of the eluent were taken into account. The boundary conditions were determined from the experimental measurements of the column inlet pressure and of the temperature profile along the column wall, which were made with a precision better than +/-0.1 K. These calculation results provide the 3-D temperature profiles along and across the columns. The axial and radial temperature gradients are discussed in relationship with the experimental conditions used. The temperature map obtained permits a prediction of the chromatographic data obtained under a very high pressure gradient.

  4. Noise-modulated self-polarization effect of impurity doped quantum dots under simultaneous presence of hydrostatic pressure and temperature

    NASA Astrophysics Data System (ADS)

    Bera, Aindrila; Ghosh, Manas

    2017-10-01

    We explore the profiles of self-polarization effect (SPE) of doped GaAs QD under simultaneous presence of hydrostatic pressure (HP), temperature and in presence of noise. Noise term carries Gaussian white character and it has been administered to the system via two different pathways; additive and multiplicative. Profiles of SPE have been monitored as a function of HP, temperature and noise strength. Under a given condition of HP and temperature, noise marks its prominent signature on the SPE profile. However, the extent to which noise affects the SPE profile visibly depends on the noise strength and the pathway through which noise is introduced. As interesting observations we have found that SPE exhibits minimization at a pressure of ∼ 170 kbar in absence of noise and at ∼ 150 kbar when noise is present. Furthermore, in presence of multiplicative noise SPE exhibits a very faint decrease with increase in T up to T ∼ 420 K. However, beyond T ∼ 420 K, further increase in temperature causes abrupt fall of SPE in a highly sharp way. The findings highlight viable ways of tuning SPE of doped QD system through subtle interplay between HP, temperature and noise.

  5. Influence of a forest canopy on velocity and temperature profiles under synoptic conditions

    NASA Astrophysics Data System (ADS)

    Pattantyus, A.; Hocut, C. M.; Wang, Y.; Creegan, E.; Krishnamurthy, R.; Otarola-Bust, S.; Leo, L. S.; Fernando, H. J. S.

    2017-12-01

    Numerous field campaigns have found the importance of surface conditions on boundary layer evolution. Specifically, soil properties were found to control surface fluxes of heat, moisture, and momentum that significantly modulated the atmospheric boundary layer (ABL) over flat and sparsely vegetated surfaces. There have been increasing numbers of studies related to canopy impacts on the boundary layer, such as CHATS, however few canopy studies over complex terrain have been performed with limited instrumentation. The recent Perdigão campaign greatly augmented the previous datasets available by instrumenting a unique, parallel ridge mountain in Perdigão, Portugal in unprecedented spatial and temporal resolution using traditional mast mounted sensors, instrumented aerial platforms, and remote sensing instrumentation. To aid the canopy studies, the Army Research Laboratory deployed sonic anemometers within the canopy transecting the ridges perpendicularly and placed five additional heavily instrumented meteorological masts on the northeast facing slope to investigate detailed slope flows. At each of these towers, there was an average of six levels of temperature, relative humidity, and wind sensors located above & below the canopy height which allowed a detailed study of the sub-canopy layer. In addition to the towers, two scanning Doppler LiDARs were oriented such that they performed synchronized dual Doppler virtual tower scans, extending from the canopy interface to several hundred meters above. Synoptically forced periods were analyzed to examine: the ABL structure of temperature, moisture, wind, and turbulent kinetic energy. Of particular interest are the shear layer at the canopy interface, recirculation events, as well as ejection and sweep events within the canopy and how these modify surface fluxes along the slopes.

  6. Site-dependent proxy response to climate change during the last 140 years observed in varved lake sediments in Northern Poland

    NASA Astrophysics Data System (ADS)

    Ott, Florian; Kramkowski, Mateusz; Wulf, Sabine; Plessen, Birgit; Serb, Johanna; Tjallingii, Rik; Schwab, Markus; Słowiński, Michał; Brykała, Dariusz; Tyszkowski, Sebastian; Putyrskaya, Victoria; Appelt, Oona; Błaszkiewicz, Mirosław; Brauer, Achim

    2017-04-01

    This accurate dating and chronological correlation using crypto-tephras provide a powerful way to compare the varved sediment records of the lakes Głęboczek (JG), Czechowskie (JC) and Jelonek (JEL) (north-central Poland). For the last 140 years, high-resolution varve micro-facies analyses (seasonal layer composition and thickness) and µ-XRF element scanning as well as bulk geochemical analyses (TOC, CaCO3) at sub-decadal to decadal resolution were conducted for all three records. Varve chronologies have been independently established by means of annual layer counting. 137Cs activity concentration measurements confirmed the varve chronology from JC. The Askja AD1875 tephra has been used to synchronize the records. A comparison of sediment data with monthly temperature data from Koszalin since 1870 and daily temperature data from Chojnice since 1951 revealed different responses of lake deposition to recent temperature change. Varves are well-preserved over the entire 140 years only in the sediments of JG, while in the JC record two faintly varved intervals are intercalated and in JEL two non-varved intervals occur at the base and top of the profile. These differences likely are due to variations in lake characteristics. Climate changes at the demise of the Little Ice Age and the recent warming since the 1980s are expressed in varve micro-facies, CaCO3 and TOC contents in the three lakes with different response times and amplitudes. This allows us to discuss the role of local parameters like lake size, bathymetry and water depth in transferring climate change signals into lake sediment records. This study is a contribution to the Virtual Institute of Integrated Climate and Landscape Evolution Analyses - ICLEA - of the Helmholtz Association, grant number VH-VI-415.

  7. Molecular dynamic simulation of Ar-Kr mixture across a rough walled nanochannel: Velocity and temperature profiles

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

    Pooja,, E-mail: pupooja16@gmail.com; Ahluwalia, P. K., E-mail: pk-ahluwalia7@yahoo.com; Pathania, Y.

    2015-05-15

    This paper presents the results from a molecular dynamics simulation of mixture of argon and krypton in the Poiseuille flow across a rough walled nanochannel. The roughness effect on liquid nanoflows has recently drawn attention The computational software used for carrying out the molecular dynamics simulations is LAMMPS. The fluid flow takes place between two parallel plates and is bounded by horizontal rough walls in one direction and periodic boundary conditions are imposed in the other two directions. Each fluid atom interacts with other fluid atoms and wall atoms through Leenard-Jones (LJ) potential with a cut off distance of 5.0.more » To derive the flow a constant force is applied whose value is varied from 0.1 to 0.3 and velocity profiles and temperature profiles are noted for these values of forces. The velocity profile and temperature profiles are also looked at different channel widths of nanochannel and at different densities of mixture. The velocity profile and temperature profile of rough walled nanochannel are compared with that of smooth walled nanochannel and it is concluded that mean velocity increases with increase in channel width, force applied and decrease in density also with introduction of roughness in the walls of nanochannel mean velocity again increases and results also agree with the analytical solution of a Poiseuille flow.« less

  8. Real-Gas Effects on Binary Mixing Layers

    NASA Technical Reports Server (NTRS)

    Okong'o, Nora; Bellan, Josette

    2003-01-01

    This paper presents a computational study of real-gas effects on the mean flow and temporal stability of heptane/nitrogen and oxygen/hydrogen mixing layers at supercritical pressures. These layers consist of two counterflowing free streams of different composition, temperature, and density. As in related prior studies reported in NASA Tech Briefs, the governing conservation equations were the Navier-Stokes equations of compressible flow plus equations for the conservation of total energy and of chemical- species masses. In these equations, the expressions for heat fluxes and chemical-species mass fluxes were derived from fluctuation-dissipation theory and incorporate Soret and Dufour effects. Similarity equations for the streamwise velocity, temperature, and mass fractions were derived as approximations to the governing equations. Similarity profiles showed important real-gas, non-ideal-mixture effects, particularly for temperature, in departing from the error-function profile, which is the similarity solution for incompressible flow. The temperature behavior was attributed to real-gas thermodynamics and variations in Schmidt and Prandtl numbers. Temporal linear inviscid stability analyses were performed using the similarity and error-function profiles as the mean flow. For the similarity profiles, the growth rates were found to be larger and the wavelengths of highest instability shorter, relative to those of the errorfunction profiles and to those obtained from incompressible-flow stability analysis. The range of unstable wavelengths was found to be larger for the similarity profiles than for the error-function profiles

  9. Molecular dynamic simulation of Ar-Kr mixture across a rough walled nanochannel: Velocity & temperature profiles

    NASA Astrophysics Data System (ADS)

    Pooja, Pathania, Y.; Ahluwalia, P. K.

    2015-05-01

    This paper presents the results from a molecular dynamics simulation of mixture of argon and krypton in the Poiseuille flow across a rough walled nanochannel. The roughness effect on liquid nanoflows has recently drawn attention The computational software used for carrying out the molecular dynamics simulations is LAMMPS. The fluid flow takes place between two parallel plates and is bounded by horizontal rough walls in one direction and periodic boundary conditions are imposed in the other two directions. Each fluid atom interacts with other fluid atoms and wall atoms through Leenard-Jones (LJ) potential with a cut off distance of 5.0. To derive the flow a constant force is applied whose value is varied from 0.1 to 0.3 and velocity profiles and temperature profiles are noted for these values of forces. The velocity profile and temperature profiles are also looked at different channel widths of nanochannel and at different densities of mixture. The velocity profile and temperature profile of rough walled nanochannel are compared with that of smooth walled nanochannel and it is concluded that mean velocity increases with increase in channel width, force applied and decrease in density also with introduction of roughness in the walls of nanochannel mean velocity again increases and results also agree with the analytical solution of a Poiseuille flow.

  10. Developing a Data Record of Lower Troposphere Temperature Profiles for Diurnal Land-Atmosphere Coupling Investigations

    NASA Astrophysics Data System (ADS)

    Lin, Z.; Li, D.

    2017-12-01

    The lower troposphere, including the planetary boundary layer, is strongly influenced by the land surface at diurnal scales. However, investigations of diurnal land-atmosphere coupling are significantly hindered by the lack of profile measurements that resolve the diurnal cycle. This study aims to bridge this gap by developing a decade-long (from 2007 to 2016) data record of diurnal temperature profiles in the lower troposphere (from the surface to about 4 km above the surface), which is based on the Aircrafts Communications Addressing and Reporting System (ACARS) meteorological observations. We first identify the number of profiles within an hour for each airport over the CONUS. At each airport, only data that passed at least level-1 quality check are retained. 40 airports out of 275 are then selected, which have data for more than 12 hours per day. These selected airports are mainly located along the east and west coasts, as expected. Because the data are recorded at irregular heights, we resample each profile in the lowest 4 km or so to pre-defined vertical coordinates. These temperature profiles are further bias-corrected by comparing to collocated radiosonde observations. This consistent data record of diurnal temperature profiles in the lower troposphere can be also used for regional climatology research, short-term weather forecasts, and numerical model evaluation.

  11. Changes in the cuticular hydrocarbon profile of the slave-maker ant queen, Polyergus breviceps emery, after killing a Formica host queen (Hymenoptera: Formicidae).

    PubMed

    Johnson, C A; Vander Meer, R K; Lavine, B

    2001-09-01

    Queens of the slave-maker ant, Polyergus breviceps, take over nests of their Formica host species by fatally attacking the resident queen. As workers only begin grooming the P. breviceps queen once she has ceased her attack, we investigated whether a change in parasite queen chemistry may account for the change in worker behavior. Cuticular hydrocarbon profiles of newly mated P. breviceps queens and of queens of their two Formica host species were found to be species-specific. Profiles of newly mated P. breviceps queens that had attacked a Formica queen, however, were virtually identical to the queen profile of the species killed. Mass spectral analysis revealed that the hydrocarbons on the cuticles of newly mated P. breviceps changed from primarily normal alkanes to methyl and di-methyl branched alkanes after attacks. The results suggest that cuticular compounds from the host queen were transferred to the parasite queen during their aggressive interaction.

  12. A data set for validation of models of laser-induced incandescence from soot: temporal profiles of LII signal and particle temperature

    NASA Astrophysics Data System (ADS)

    Goulay, Fabien; Schrader, Paul E.; López-Yglesias, Xerxes; Michelsen, Hope A.

    2013-09-01

    We measured spectrally and temporally resolved laser-induced incandescence signals from flame-generated soot at laser fluences of 0.01-3.5 J/cm2 and laser wavelengths of 532 and 1,064 nm. We recorded LII temporal profiles at 681.8 nm using a fast-gated detector and a spatially homogeneous and temporally smooth laser profile. Time-resolved emission spectra were used to identify and avoid spectral interferences and to infer soot temperatures. Soot temperatures reach a maximum of 4,415 ± 65 K at fluences ≥0.2 J/cm2 at 532 nm and 4,424 ± 80 K at fluences ≥0.3 J/cm2 at 1,064 nm. These temperatures are consistent with the sublimation temperature of C2 of 4,456.59 K. At fluences above 0.5 J/cm2 at 532 nm, the measured spectra yield an apparent higher temperature after the soot has fully vaporized but well within the laser pulse. This apparent temperature elevation at high fluence is explained by fluorescence interferences from molecules present in the flame. We also measured 3-color LII temporal profiles at detection wavelengths of 451.5, 681.8, and 854.8 nm. The temperatures inferred from these measurements agree well with those measured using spectrally resolved LII. The data discussed in this manuscript are archived as electronic supplementary material.

  13. AROTAL Ozone and Temperature Vertical Profile Measurements from the NASA DC-8 during the SOLVE II Campaign

    NASA Technical Reports Server (NTRS)

    McGee, Thomas J.; Twigg, Laurence; Sumnicht, Grant; Hoegy, Walter; Burris, John; Silbert, Donald; Heaps, William; Neuber, R.; Trepte, C. R.

    2004-01-01

    The AROTAL instrument (Airborne Raman Ozone Temperature and Aerosol Lidar) - a collaboration between scientists at NASA Goddard Space Flight Center, and Langley Research Center - was flown on the NASA DC-8 during the SOLVE II Campaign during January and February, 2003. The flights were flown from the Arena Arctica in Kiruna, Sweden. We report measurements of temperature and ozone profiles showing approximately a 600 ppbv loss in ozone near 17.5 km, over the time frame of the aircraft campaign. Comparisons of ozone profiles from AROTAL are made with the SAGE III instrument.

  14. Could multiple voids explain the cosmic microwave background Cold Spot anomaly?

    DOE PAGES

    Naidoo, Krishna; Benoit-Levy, Aurelien; Lahav, Ofer

    2016-03-20

    Understanding the observed Cold Spot (CS) (temperature of ~ -150 mu K at its centre) on the Cosmic Microwave Background (CMB) is an outstanding problem. Explanations vary from assuming it is just a ≳ 3σ primordial Gaussian fluctuation to the imprint of a supervoid via the Integrated Sachs-Wolfe and Rees-Sciama (ISW+RS) effects. Since single spherical supervoids cannot account for the full profile, the ISW+RS of multiple line-of-sight voids is studied here to mimic the structure of the cosmic web. Two structure configurations are considered. The first, through simulations of 20 voids, produces a central mean temperature of ~-50 mu K.more » In this model the central CS temperature lies at ~ 2σ but fails to explain the CS hot ring. An alternative multi-void model (using more pronounced compensated voids) produces much smaller temperature profiles, but contains a prominent hot ring. Arrangements containing closely placed voids at low redshift are found to be particularly well suited to produce CS-like profiles. We then measure the significance of the CS if CS-like profiles (which are fitted to the ISW+RS of multi-void scenarios) are removed. Furthermore, the CS tension with the LCDM model can be reduced dramatically for an array of temperature profiles smaller than the CS itself.« less

  15. Boron depth profiles and residual damage following rapid thermal annealing of low-temperature BSi molecular ion implantation in silicon

    NASA Astrophysics Data System (ADS)

    Liang, J. H.; Wang, S. C.

    2007-08-01

    The influence of substrate temperature on both the implantation and post-annealing characteristics of molecular-ion-implanted 5 × 1014 cm-2 77 keV BSi in silicon was investigated in terms of boron depth profiles and damage microstructures. The substrate temperatures under investigation consisted of room temperature (RT) and liquid nitrogen temperature (LT). Post-annealing treatments were performed using rapid thermal annealing (RTA) at 1050 °C for 25 s. Boron depth profiles and damage microstructures in both the as-implanted and as-annealed specimens were determined using secondary ion mass spectrometry (SIMS) and transmission electron microscopy (TEM), respectively. The as-implanted results revealed that, compared to the RT specimen, the LT specimen yields a shallower boron depth profile with a reduced tail into the bulk. An amorphous layer containing a smooth amorphous-to-crystalline (a/c) interface is evident in the LT specimen while just the opposite is true in the as-implanted RT one. The as-annealed results illustrated that the extension of the boron depth profile into the bulk via transient-enhanced diffusion (TED) in the LT specimen is less than it is in the RT one. Only residual defects are visible in the LT specimen while two clear bands of dislocation loops appear in the RT one.

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

    Naidoo, Krishna; Benoit-Levy, Aurelien; Lahav, Ofer

    Understanding the observed Cold Spot (CS) (temperature of ~ -150 mu K at its centre) on the Cosmic Microwave Background (CMB) is an outstanding problem. Explanations vary from assuming it is just a ≳ 3σ primordial Gaussian fluctuation to the imprint of a supervoid via the Integrated Sachs-Wolfe and Rees-Sciama (ISW+RS) effects. Since single spherical supervoids cannot account for the full profile, the ISW+RS of multiple line-of-sight voids is studied here to mimic the structure of the cosmic web. Two structure configurations are considered. The first, through simulations of 20 voids, produces a central mean temperature of ~-50 mu K.more » In this model the central CS temperature lies at ~ 2σ but fails to explain the CS hot ring. An alternative multi-void model (using more pronounced compensated voids) produces much smaller temperature profiles, but contains a prominent hot ring. Arrangements containing closely placed voids at low redshift are found to be particularly well suited to produce CS-like profiles. We then measure the significance of the CS if CS-like profiles (which are fitted to the ISW+RS of multi-void scenarios) are removed. Furthermore, the CS tension with the LCDM model can be reduced dramatically for an array of temperature profiles smaller than the CS itself.« less

  17. VLSI Design of Trusted Virtual Sensors.

    PubMed

    Martínez-Rodríguez, Macarena C; Prada-Delgado, Miguel A; Brox, Piedad; Baturone, Iluminada

    2018-01-25

    This work presents a Very Large Scale Integration (VLSI) design of trusted virtual sensors providing a minimum unitary cost and very good figures of size, speed and power consumption. The sensed variable is estimated by a virtual sensor based on a configurable and programmable PieceWise-Affine hyper-Rectangular (PWAR) model. An algorithm is presented to find the best values of the programmable parameters given a set of (empirical or simulated) input-output data. The VLSI design of the trusted virtual sensor uses the fast authenticated encryption algorithm, AEGIS, to ensure the integrity of the provided virtual measurement and to encrypt it, and a Physical Unclonable Function (PUF) based on a Static Random Access Memory (SRAM) to ensure the integrity of the sensor itself. Implementation results of a prototype designed in a 90-nm Complementary Metal Oxide Semiconductor (CMOS) technology show that the active silicon area of the trusted virtual sensor is 0.86 mm 2 and its power consumption when trusted sensing at 50 MHz is 7.12 mW. The maximum operation frequency is 85 MHz, which allows response times lower than 0.25 μ s. As application example, the designed prototype was programmed to estimate the yaw rate in a vehicle, obtaining root mean square errors lower than 1.1%. Experimental results of the employed PUF show the robustness of the trusted sensing against aging and variations of the operation conditions, namely, temperature and power supply voltage (final value as well as ramp-up time).

  18. VLSI Design of Trusted Virtual Sensors

    PubMed Central

    2018-01-01

    This work presents a Very Large Scale Integration (VLSI) design of trusted virtual sensors providing a minimum unitary cost and very good figures of size, speed and power consumption. The sensed variable is estimated by a virtual sensor based on a configurable and programmable PieceWise-Affine hyper-Rectangular (PWAR) model. An algorithm is presented to find the best values of the programmable parameters given a set of (empirical or simulated) input-output data. The VLSI design of the trusted virtual sensor uses the fast authenticated encryption algorithm, AEGIS, to ensure the integrity of the provided virtual measurement and to encrypt it, and a Physical Unclonable Function (PUF) based on a Static Random Access Memory (SRAM) to ensure the integrity of the sensor itself. Implementation results of a prototype designed in a 90-nm Complementary Metal Oxide Semiconductor (CMOS) technology show that the active silicon area of the trusted virtual sensor is 0.86 mm2 and its power consumption when trusted sensing at 50 MHz is 7.12 mW. The maximum operation frequency is 85 MHz, which allows response times lower than 0.25 μs. As application example, the designed prototype was programmed to estimate the yaw rate in a vehicle, obtaining root mean square errors lower than 1.1%. Experimental results of the employed PUF show the robustness of the trusted sensing against aging and variations of the operation conditions, namely, temperature and power supply voltage (final value as well as ramp-up time). PMID:29370141

  19. Soil Water and Temperature System (SWATS) Instrument Handbook

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

    Cook, David R.

    2016-04-01

    The soil water and temperature system (SWATS) provides vertical profiles of soil temperature, soil-water potential, and soil moisture as a function of depth below the ground surface at hourly intervals. The temperature profiles are measured directly by in situ sensors at the Central Facility and many of the extended facilities of the U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility Southern Great Plains (SGP) site. The soil-water potential and soil moisture profiles are derived from measurements of soil temperature rise in response to small inputs of heat. Atmospheric scientists use the data in climate models tomore » determine boundary conditions and to estimate the surface energy flux. The data are also useful to hydrologists, soil scientists, and agricultural scientists for determining the state of the soil.« less

  20. Temperature profile of graphite surface burning in a stream of oxygen

    NASA Technical Reports Server (NTRS)

    Kisch, D.

    1978-01-01

    Using methods for the objective measurement of the spectrum line reversal temperature in burning gases, the temperature profile at a graphite surface burning in a stream of oxygen was measured. From the behavior of the reversal temperature, it follows that particles in long-lived, high-energy states are present in the burning gas, and these bring about an overexcitation of the atomic species emitting the reversal line. Qualitative measurements show that a temperature maximum occurs at the expected distance of 1-2 mm from the graphite surface.

  1. Measurements of temperature profiles at the exit of small rockets.

    PubMed

    Griggs, M; Harshbarger, F C

    1966-02-01

    The sodium line reversal technique was used to determine the reversal temperature profile across the exit of small rockets. Measurements were made on one 73-kg thrust rocket, and two 23-kg thrust rockets with different injectors. The large rocket showed little variation of reversal temperature across the plume. However, the 23-kg rockets both showed a large decrease of reversal temperature from the axis to the edge of the plume. In addition, the sodium line reversal technique of temperature measurement was compared with an infrared technique developed in these laboratories.

  2. PARRoT- a homology-based strategy to quantify and compare RNA-sequencing from non-model organisms.

    PubMed

    Gan, Ruei-Chi; Chen, Ting-Wen; Wu, Timothy H; Huang, Po-Jung; Lee, Chi-Ching; Yeh, Yuan-Ming; Chiu, Cheng-Hsun; Huang, Hsien-Da; Tang, Petrus

    2016-12-22

    Next-generation sequencing promises the de novo genomic and transcriptomic analysis of samples of interests. However, there are only a few organisms having reference genomic sequences and even fewer having well-defined or curated annotations. For transcriptome studies focusing on organisms lacking proper reference genomes, the common strategy is de novo assembly followed by functional annotation. However, things become even more complicated when multiple transcriptomes are compared. Here, we propose a new analysis strategy and quantification methods for quantifying expression level which not only generate a virtual reference from sequencing data, but also provide comparisons between transcriptomes. First, all reads from the transcriptome datasets are pooled together for de novo assembly. The assembled contigs are searched against NCBI NR databases to find potential homolog sequences. Based on the searched result, a set of virtual transcripts are generated and served as a reference transcriptome. By using the same reference, normalized quantification values including RC (read counts), eRPKM (estimated RPKM) and eTPM (estimated TPM) can be obtained that are comparable across transcriptome datasets. In order to demonstrate the feasibility of our strategy, we implement it in the web service PARRoT. PARRoT stands for Pipeline for Analyzing RNA Reads of Transcriptomes. It analyzes gene expression profiles for two transcriptome sequencing datasets. For better understanding of the biological meaning from the comparison among transcriptomes, PARRoT further provides linkage between these virtual transcripts and their potential function through showing best hits in SwissProt, NR database, assigning GO terms. Our demo datasets showed that PARRoT can analyze two paired-end transcriptomic datasets of approximately 100 million reads within just three hours. In this study, we proposed and implemented a strategy to analyze transcriptomes from non-reference organisms which offers the opportunity to quantify and compare transcriptome profiles through a homolog based virtual transcriptome reference. By using the homolog based reference, our strategy effectively avoids the problems that may cause from inconsistencies among transcriptomes. This strategy will shed lights on the field of comparative genomics for non-model organism. We have implemented PARRoT as a web service which is freely available at http://parrot.cgu.edu.tw .

  3. Earth Adventure: Virtual Globe-based Suborbital Atmospheric Greenhouse Gases Exploration

    NASA Astrophysics Data System (ADS)

    Wei, Y.; Landolt, K.; Boyer, A.; Santhana Vannan, S. K.; Wei, Z.; Wang, E.

    2016-12-01

    The Earth Venture Suborbital (EVS) mission is an important component of NASA's Earth System Science Pathfinder program that aims at making substantial advances in Earth system science through measurements from suborbital platforms and modeling researches. For example, the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) project of EVS-1 collected measurements of greenhouse gases (GHG) on local to regional scales in the Alaskan Arctic. The Atmospheric Carbon and Transport - America (ACT-America) project of EVS-2 will provide advanced, high-resolution measurements of atmospheric profiles and horizontal gradients of CO2 and CH4.As the long-term archival center for CARVE and the future ACT-America data, the Oak Ridge National Laboratory Distributed Active Archive Center (ORNL DAAC) has been developing a versatile data management system for CARVE data to maximize their usability. One of these efforts is the virtual globe-based Suborbital Atmospheric GHG Exploration application. It leverages Google Earth to simulate the 185 flights flew by the C-23 Sherpa aircraft in 2012-2015 for the CARVE project. Based on Google Earth's 3D modeling capability and the precise coordinates, altitude, pitch, roll, and heading info of the aircraft recorded in every second during each flight, the application provides users accurate and vivid simulation of flight experiences, with an active 3D visualization of a C-23 Sherpa aircraft in view. This application provides dynamic visualization of GHG, including CO2, CO, H2O, and CH4 captured during the flights, at the same pace of the flight simulation in Google Earth. Photos taken during those flights are also properly displayed along the flight paths. In the future, this application will be extended to incorporate more complicated GHG measurements (e.g. vertical profiles) from the ACT-America project. This application leverages virtual globe technology to provide users an integrated framework to interactively explore information about GHG measurements and to link scientific measurements to the rich virtual planet environment provided by Google Earth. Positive feedbacks have been received from users. It provides a good example of extending basic data visualization into a knowledge discovery experience and maximizing the usability of Earth science observations.

  4. Thermodynamic and liquid profiling during the 2010 Winter Olympics

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

    Ware, R.; Cimini, D.; Campos, E.

    2013-10-01

    Tropospheric observations by a microwave profiling radiometer and six-hour radiosondes were obtained during the Alpine Venue of the 2010 Winter Olympic Games at Whistler, British Columbia, by Environment Canada. The radiometer provided continuous temperature, humidity and liquid (water) profiles during all weather conditions including rain, sleet and snow. Gridded analysis was provided by the U.S. National Oceanic and Atmospheric Administration. We compare more than two weeks of radiometer neural network and radiosonde temperature and humidity soundings including clear and precipitating conditions. Corresponding radiometer liquid and radiosonde wind soundings are shown. Close correlation is evident between radiometer and radiosonde temperature andmore » humidity profiles up to 10 km height and among southwest winds, liquid water and upper level thermodynamics, consistent with up-valley advection and condensation of moist maritime air. We compare brightness temperatures observed by the radiometer and forward-modeled from radiosonde and gridded analysis. Radiosonde-equivalent observation accuracy is demonstrated for radiometer neural network temperature and humidity retrievals up to 800 m height and for variational retrievals that combine radiometer and gridded analysis up to 10 km height« less

  5. Temperature distribution in an aircraft tire at low ground speeds

    NASA Technical Reports Server (NTRS)

    Mccarty, J. L.; Tanner, J. A.

    1983-01-01

    An experimental study was conducted to define temperature profiles of 22 x 5.5, type 7, bias ply aircraft tires subjected to freely rolling, yawed rolling, and light braking conditions. Temperatures along the inner wall of freely rolling tires were greater than those near the outer surface. The effect of increasing tire deflection was to increase the temperature within the shoulder and sidewall areas of the tire carcass. The effect of cornering and braking was to increase the treat temperature. For taxi operations at fixed yaw angles, temperature profiles were not symmetric. Increasing the ground speed produced only moderate increases in tread temperature, whereas temperatures in the carcass shoulder and sidewall were essentially unaffected.

  6. The Implications of 3D Thermal Structure on 1D Atmospheric Retrieval

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

    Blecic, Jasmina; Dobbs-Dixon, Ian; Greene, Thomas, E-mail: jasmina@nyu.edu

    Using the atmospheric structure from a 3D global radiation-hydrodynamic simulation of HD 189733b and the open-source Bayesian Atmospheric Radiative Transfer (BART) code, we investigate the difference between the secondary-eclipse temperature structure produced with a 3D simulation and the best-fit 1D retrieved model. Synthetic data are generated by integrating the 3D models over the Spitzer , the Hubble Space Telescope ( HST ), and the James Web Space Telescope ( JWST ) bandpasses, covering the wavelength range between 1 and 11 μ m where most spectroscopically active species have pronounced features. Using the data from different observing instruments, we present detailedmore » comparisons between the temperature–pressure profiles recovered by BART and those from the 3D simulations. We calculate several averages of the 3D thermal structure and explore which particular thermal profile matches the retrieved temperature structure. We implement two temperature parameterizations that are commonly used in retrieval to investigate different thermal profile shapes. To assess which part of the thermal structure is best constrained by the data, we generate contribution functions for our theoretical model and each of our retrieved models. Our conclusions are strongly affected by the spectral resolution of the instruments included, their wavelength coverage, and the number of data points combined. We also see some limitations in each of the temperature parametrizations, as they are not able to fully match the complex curvatures that are usually produced in hydrodynamic simulations. The results show that our 1D retrieval is recovering a temperature and pressure profile that most closely matches the arithmetic average of the 3D thermal structure. When we use a higher resolution, more data points, and a parametrized temperature profile that allows more flexibility in the middle part of the atmosphere, we find a better match between the retrieved temperature and pressure profile and the arithmetic average. The Spitzer and HST simulated observations sample deep parts of the planetary atmosphere and provide fewer constraints on the temperature and pressure profile, while the JWST observations sample the middle part of the atmosphere, providing a good match with the middle and most complex part of the arithmetic average of the 3D temperature structure.« less

  7. Extending MGS-TES Temperature Retrievals in the Martian Atmosphere up to 90 Km: Retrieval Approach and Results

    NASA Technical Reports Server (NTRS)

    Feofilov, A. G.; Kutepov, A. A.; Rezac, L.; Smith, M. D.

    2015-01-01

    This paper describes a methodology for performing a temperature retrieval in the Martian atmosphere in the 50-90 km altitude range using spectrally integrated 15 micrometers C02 limb emissions measured by the Thermal Emission Spectrometer (TES), the thermal infrared spectrometer on board the Mars Global Surveyor (MGS). We demonstrate that temperature retrievals from limb observations in the 75-90 km altitude range require accounting for the non-local thermodynamic equilibrium (non-LTE) populations of the C02(v2) vibrational levels. Using the methodology described in the paper, we have retrieved approximately 1200 individual temperature profiles from MGS TES limb observations in the altitude range between 60 and 90 km. 0ur dataset of retrieved temperature profiles is available for download in supplemental materials of this paper. The temperature retrieval uncertainties are mainly caused by radiance noise, and are estimated to be about 2 K at 60 km and below, 4 K at 70 km, 7 K at 80 km, 10 K at 85 km, and 20 K at 90 km. We compare the retrieved profiles to Mars Climate Database temperature profiles and find good qualitative agreement. Quantitatively, our retrieved profiles are in general warmer and demonstrate strong variability with the following values for bias and standard deviations (in brackets) compared to the Martian Year 24 dataset of the Mars Climate Database: 6 (+/-20) K at 60 km, 7.5 (+/-25) K at 65 km, 9 (+/-27) K at 70 km, 9.5 (+/-27) K at 75 km, 10 (+/-28) K at 80 km, 11 (+/-29) K at 85 km, and 11.5 (+/-31) K at 90 km. Possible reasons for the positive temperature bias are discussed. carbon dioxide molecular vibrations

  8. Parameter studies on the energy balance closure problem using large-eddy simulation

    NASA Astrophysics Data System (ADS)

    De Roo, Frederik; Banerjee, Tirtha; Mauder, Matthias

    2017-04-01

    The imbalance of the surface energy budget in eddy-covariance measurements is still a pending problem. A possible cause is the presence of land surface heterogeneity. Heterogeneities of the boundary layer scale or larger are most effective in influencing the boundary layer turbulence, and large-eddy simulations have shown that secondary circulations within the boundary layer can affect the surface energy budget. However, the precise influence of the surface characteristics on the energy imbalance and its partitioning is still unknown. To investigate the influence of surface variables on all the components of the flux budget under convective conditions, we set up a systematic parameter study by means of large-eddy simulation. For the study we use a virtual control volume approach, and we focus on idealized heterogeneity by considering spatially variable surface fluxes. The surface fluxes vary locally in intensity and these patches have different length scales. The main focus lies on heterogeneities of length scales of the kilometer scale and one decade smaller. For each simulation, virtual measurement towers are positioned at functionally different positions. We discriminate between the locally homogeneous towers, located within land use patches, with respect to the more heterogeneous towers, and find, among others, that the flux-divergence and the advection are strongly linearly related within each class. Furthermore, we seek correlators for the energy balance ratio and the energy residual in the simulations. Besides the expected correlation with measurable atmospheric quantities such as the friction velocity, boundary-layer depth and temperature and moisture gradients, we have also found an unexpected correlation with the temperature difference between sonic temperature and surface temperature. In additional simulations with a large number of virtual towers, we investigate higher order correlations, which can be linked to secondary circulations. In a companion presentation (EGU2017-2130) these correlations are investigated and confirmed with the help of micrometeorological measurements from the TERENO sites where the effects of landscape scale surface heterogeneities are deemed to be important.

  9. Air-condition Control System of Weaving Workshop Based on LabVIEW

    NASA Astrophysics Data System (ADS)

    Song, Jian

    The project of air-condition measurement and control system based on LabVIEW is put forward for the sake of controlling effectively the environmental targets in the weaving workshop. In this project, which is based on the virtual instrument technology and in which LabVIEW development platform by NI is adopted, the system is constructed on the basis of the virtual instrument technology. It is composed of the upper PC, central control nodes based on CC2530, sensor nodes, sensor modules and executive device. Fuzzy control algorithm is employed to achieve the accuracy control of the temperature and humidity. A user-friendly man-machine interaction interface is designed with virtual instrument technology at the core of the software. It is shown by experiments that the measurement and control system can run stably and reliably and meet the functional requirements for controlling the weaving workshop.

  10. Multi-layer thermoelectric-temperature-mapping microbial incubator designed for geo-biochemistry applications.

    PubMed

    Wu, Jin-Gen; Liu, Man-Chi; Tsai, Ming-Fei; Yu, Wei-Shun; Chen, Jian-Zhang; Cheng, I-Chun; Lin, Pei-Chun

    2012-04-01

    We demonstrate a novel, vertical temperature-mapping incubator utilizing eight layers of thermoelectric (TE) modules mounted around a test tube. The temperature at each layer of the TE module is individually controlled to simulate the vertical temperature profile of geo-temperature variations with depth. Owing to the constraint of non-intrusion to the filled geo-samples, the temperature on the tube wall is adopted for measurement feedback. The design considerations for the incubator include spatial arrangement of the energy transfer mechanism, heating capacity of the TE modules, minimum required sample amount for follow-up instrumental or chemical analysis, and the constraint of non-intrusion to the geo-samples during incubation. The performance of the incubator is experimentally evaluated with two tube conditions and under four preset temperature profiles. Test tubes are either empty or filled with quartz sand, which has comparable thermal properties to the materials in the geo-environment. The applied temperature profiles include uniform, constant temperature gradient, monotonic-increasing parabolic, and parabolic. The temperature on the tube wall can be controlled between 20 °C and 90 °C with an averaged root mean squared error of 1 °C. © 2012 American Institute of Physics

  11. A thermal profile method to identify potential ground-water discharge areas and preferred salmonid habitats for long river reaches

    USGS Publications Warehouse

    Vaccaro, J.J.; Maloy, K.J.

    2006-01-01

    The thermal regime of riverine systems is a major control on aquatic ecosystems. Ground water discharge is an important abiotic driver of the aquatic ecosystem because it provides preferred thermal structure and habitat for different types of fish at different times in their life history. In large diverse river basins with an extensive riverine system, documenting the thermal regime and ground-water discharge is difficult and problematic. A method was developed to thermally profile long (5-25 kilometers) river reaches by towing in a Lagrangian framework one or two probes that measure temperature, depth, and conductivity. One probe is towed near the streambed and, if used, a second probe is towed near the surface. The probes continuously record data at 1-3-second intervals while a Global Positioning System logs spatial coordinates. The thermal profile provides valuable information about spatial and temporal variations in habitat, and, notably, indicates ground-water discharge areas. This method was developed and tested in the Yakima River Basin, Washington, in summer 2001 during low flows in an extreme drought year. The temperature profile comprehensively documents the longitudinal distribution of a river's temperature regime that cannot be captured by fixed station data. The example profile presented exhibits intra-reach diversity that reflects the many factors controlling the temperature of a parcel of water as it moves downstream. Thermal profiles provide a new perspective on riverine system temperature regimes that represent part of the aquatic habitat template for lotic community patterns.

  12. Low-temperature plasma technology as part of a closed-loop resource management system

    NASA Technical Reports Server (NTRS)

    Hetland, Melanie D.; Rindt, John R.; Jones, Frank A.; Sauer, Randal S.

    1990-01-01

    The results of this testing indicate that the agitated low-temperature plasma reactor system successfully converted carbon, hydrogen, and nitrogen into gaseous products at residence times that were about ten times shorter than those achieved by stationary processing. The inorganic matrix present was virtually unchanged by the processing technique. It was concluded that this processing technique is feasible for use as part of a close-looped processing resource management system.

  13. Eliminating the Cuspidal Temperature Profile of a Non-equilibrium Chain

    NASA Astrophysics Data System (ADS)

    Cândido, Michael M.; M. Morgado, Welles A.; Duarte Queirós, Sílvio M.

    2017-06-01

    In 1967, Z. Rieder, J. L. Lebowitz, and E. Lieb (RLL) introduced a model of heat conduction on a crystal that became a milestone problem of non-equilibrium statistical mechanics. Along with its inability to reproduce Fourier's law—which subsequent generalizations have been trying to amend—the RLL model is also characterized by awkward cusps at the ends of the non-equilibrium chain, an effect that has endured all these years without a satisfactory answer. In this paper, we first show that such trait stems from the insufficiency of pinning interactions between the chain and the substrate. Assuming the possibility of pinning the chain, the analysis of the temperature profile in the space of parameters reveals that for a proper combination of the border and bulk pinning values, the temperature profile may shift twice between the RLL cuspidal behavior and the expected monotonic local temperature evolution along the system, as a function of the pinning. At those inversions, the temperature profile along the chain is characterized by perfect plateaux: at the first threshold, the cumulants of the heat flux reach their maxima and the vanishing of the two-point velocity correlation function for all sites of the chain so that the system behaves similarly to a "phonon box." On the other hand, at the second change of the temperature profile, we still have the vanishing of the two-point correlation function but only for the bulk, which explains the emergence of the temperature plateau and thwarts the reaching of the maximal values of the cumulants of the heat flux.

  14. A framework for different levels of integration of computational models into web-based virtual patients.

    PubMed

    Kononowicz, Andrzej A; Narracott, Andrew J; Manini, Simone; Bayley, Martin J; Lawford, Patricia V; McCormack, Keith; Zary, Nabil

    2014-01-23

    Virtual patients are increasingly common tools used in health care education to foster learning of clinical reasoning skills. One potential way to expand their functionality is to augment virtual patients' interactivity by enriching them with computational models of physiological and pathological processes. The primary goal of this paper was to propose a conceptual framework for the integration of computational models within virtual patients, with particular focus on (1) characteristics to be addressed while preparing the integration, (2) the extent of the integration, (3) strategies to achieve integration, and (4) methods for evaluating the feasibility of integration. An additional goal was to pilot the first investigation of changing framework variables on altering perceptions of integration. The framework was constructed using an iterative process informed by Soft System Methodology. The Virtual Physiological Human (VPH) initiative has been used as a source of new computational models. The technical challenges associated with development of virtual patients enhanced by computational models are discussed from the perspectives of a number of different stakeholders. Concrete design and evaluation steps are discussed in the context of an exemplar virtual patient employing the results of the VPH ARCH project, as well as improvements for future iterations. The proposed framework consists of four main elements. The first element is a list of feasibility features characterizing the integration process from three perspectives: the computational modelling researcher, the health care educationalist, and the virtual patient system developer. The second element included three integration levels: basic, where a single set of simulation outcomes is generated for specific nodes in the activity graph; intermediate, involving pre-generation of simulation datasets over a range of input parameters; advanced, including dynamic solution of the model. The third element is the description of four integration strategies, and the last element consisted of evaluation profiles specifying the relevant feasibility features and acceptance thresholds for specific purposes. The group of experts who evaluated the virtual patient exemplar found higher integration more interesting, but at the same time they were more concerned with the validity of the result. The observed differences were not statistically significant. This paper outlines a framework for the integration of computational models into virtual patients. The opportunities and challenges of model exploitation are discussed from a number of user perspectives, considering different levels of model integration. The long-term aim for future research is to isolate the most crucial factors in the framework and to determine their influence on the integration outcome.

  15. A Framework for Different Levels of Integration of Computational Models Into Web-Based Virtual Patients

    PubMed Central

    Narracott, Andrew J; Manini, Simone; Bayley, Martin J; Lawford, Patricia V; McCormack, Keith; Zary, Nabil

    2014-01-01

    Background Virtual patients are increasingly common tools used in health care education to foster learning of clinical reasoning skills. One potential way to expand their functionality is to augment virtual patients’ interactivity by enriching them with computational models of physiological and pathological processes. Objective The primary goal of this paper was to propose a conceptual framework for the integration of computational models within virtual patients, with particular focus on (1) characteristics to be addressed while preparing the integration, (2) the extent of the integration, (3) strategies to achieve integration, and (4) methods for evaluating the feasibility of integration. An additional goal was to pilot the first investigation of changing framework variables on altering perceptions of integration. Methods The framework was constructed using an iterative process informed by Soft System Methodology. The Virtual Physiological Human (VPH) initiative has been used as a source of new computational models. The technical challenges associated with development of virtual patients enhanced by computational models are discussed from the perspectives of a number of different stakeholders. Concrete design and evaluation steps are discussed in the context of an exemplar virtual patient employing the results of the VPH ARCH project, as well as improvements for future iterations. Results The proposed framework consists of four main elements. The first element is a list of feasibility features characterizing the integration process from three perspectives: the computational modelling researcher, the health care educationalist, and the virtual patient system developer. The second element included three integration levels: basic, where a single set of simulation outcomes is generated for specific nodes in the activity graph; intermediate, involving pre-generation of simulation datasets over a range of input parameters; advanced, including dynamic solution of the model. The third element is the description of four integration strategies, and the last element consisted of evaluation profiles specifying the relevant feasibility features and acceptance thresholds for specific purposes. The group of experts who evaluated the virtual patient exemplar found higher integration more interesting, but at the same time they were more concerned with the validity of the result. The observed differences were not statistically significant. Conclusions This paper outlines a framework for the integration of computational models into virtual patients. The opportunities and challenges of model exploitation are discussed from a number of user perspectives, considering different levels of model integration. The long-term aim for future research is to isolate the most crucial factors in the framework and to determine their influence on the integration outcome. PMID:24463466

  16. Temperature compensation analysis of liquid lens for variable-focus control

    NASA Astrophysics Data System (ADS)

    Chen, Shu-Jung; Tai, Tsai-Lin; Shen, Chih-Hsiung

    2006-01-01

    In this work, a fabrication and temperature compensation analysis and electrowetting for the liquid lenses is proposed. The unique capability of controlling the lens profile during the electrowetting fabrication processes is successfully demonstrated for different ambient temperature environment. For a lens fabricated on a hydrophobic Teflon layer, it is found that when the applied voltage is increased, the focal length increases, and the curvature decreases. One challenge for the liquid lens is operating temperature range. Due to the environment temperature change, the ability of controlling the lens profile is analyzed and measured. The description of change in contact angle corresponding to the variation of ambient temperature is derived. Based on this description, we firstly derive the control of voltage vs. temperature for a fixed dioptric power. The control of lens during a focusing action was studied by observation of the image formed by the light through the transparent bottom of ITO glass. Under several conditions of ambient temperature change, capability of controlling the lens profile for a fixed focus is successfully demonstrated by experiments.

  17. A novel resource sharing algorithm based on distributed construction for radiant enclosure problems

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

    Finzell, Peter; Bryden, Kenneth M.

    This study demonstrates a novel approach to solving inverse radiant enclosure problems based on distributed construction. Specifically, the problem of determining the temperature distribution needed on the heater surfaces to achieve a desired design surface temperature profile is recast as a distributed construction problem in which a shared resource, temperature, is distributed by computational agents moving blocks. The sharing of blocks between agents enables them to achieve their desired local state, which in turn achieves the desired global state. Each agent uses the current state of their local environment and a simple set of rules to determine when to exchangemore » blocks, each block representing a discrete unit of temperature change. This algorithm is demonstrated using the established two-dimensional inverse radiation enclosure problem. The temperature profile on the heater surfaces is adjusted to achieve a desired temperature profile on the design surfaces. The resource sharing algorithm was able to determine the needed temperatures on the heater surfaces to obtain the desired temperature distribution on the design surfaces in the nine cases examined.« less

  18. A novel resource sharing algorithm based on distributed construction for radiant enclosure problems

    DOE PAGES

    Finzell, Peter; Bryden, Kenneth M.

    2017-03-06

    This study demonstrates a novel approach to solving inverse radiant enclosure problems based on distributed construction. Specifically, the problem of determining the temperature distribution needed on the heater surfaces to achieve a desired design surface temperature profile is recast as a distributed construction problem in which a shared resource, temperature, is distributed by computational agents moving blocks. The sharing of blocks between agents enables them to achieve their desired local state, which in turn achieves the desired global state. Each agent uses the current state of their local environment and a simple set of rules to determine when to exchangemore » blocks, each block representing a discrete unit of temperature change. This algorithm is demonstrated using the established two-dimensional inverse radiation enclosure problem. The temperature profile on the heater surfaces is adjusted to achieve a desired temperature profile on the design surfaces. The resource sharing algorithm was able to determine the needed temperatures on the heater surfaces to obtain the desired temperature distribution on the design surfaces in the nine cases examined.« less

  19. SolarSyngas: Results from a virtual institute developing materials and key components for solar thermochemical fuel production

    NASA Astrophysics Data System (ADS)

    Roeb, Martin; Steinfeld, Aldo; Borchardt, Günter; Feldmann, Claus; Schmücker, Martin; Sattler, Christian; Pitz-Paal, Robert

    2016-05-01

    The Helmholtz Virtual Institute (VI) SolarSynGas brings together expertise from solar energy research and materials science to develop metal oxide based redox materials and to integrate them in a suitable way into related process technologies for two-step thermochemical production of hydrogen and carbon monoxide from water and CO2. One of the foci of experimental investigation was exploring the impact of doping on the feasibility of ceria-based materials - mainly by Zr-doping. The results indicate that a certain Zr-content enhances the reducibility and therefore the splitting performance. Increasing the Zr-content to x = 0.15 improved the specific CO2-splitting performance by 50% compared to pure ceria. This finding agrees with theoretical studies attributing the improvements to lattice modification caused by the introduction of Zr4+. Thermogravimetric relaxation experiments and equilibrium oxygen isotope exchange experiments with subsequent depth profiling analysis were carried out on ceria. As a result the reduction reaction of even dense samples of pure ceria with a grain size of about 20 µm is surface reaction controlled. The structure of the derived expression for the apparent activation energy suggests that the chemical surface exchange coefficient should show only a very weak dependence on temperature for ceria doped with lower valence cations. A solar receiver reactor exhibiting a foam-type reticulated porous ceramics made of ceria was tested. It could be shown that applying dual-scale porosity to those foams with mm-size pores for effective radiative heat transfer during reduction and μm-size pores within its struts for enhanced kinetics during oxidation allows enhancing the performance of the reactor significantly. Also a particle process concept applying solid-solid heat recovery from redox particles in a high temperature solar thermochemical process was analysed that uses ceramic spheres as solid heat transfer medium. This concept can be implemented into any particle reactor and offers sufficiently high heat recovery rates and thus high overall system efficiencies. A detailed model to calculate the performance of the concept in consideration of temperature dependent material data and several other influencing factors was developed. It was found that the molar flow ratio needs to be optimized regarding the contact time and the heat recovery rate only increases slightly over a contact time of τ=10s. The system reaches a heat recovery rate over 70% in case of six stages, connected in a quasi-counter-current principle.

  20. Climate Golden Age or Greenhouse Gas Dark Age Legacy?

    NASA Astrophysics Data System (ADS)

    Carter, P.

    2016-12-01

    Relying on the IPCC Assessments, this paper assesses legacy from total committed global warming over centuries, correlated with comprehensive projected impacts. Socio-economic inertia, climate system inertia, atmospheric greenhouse gas (GHG) concentrations, amplifying feedback emissions, and unmasking of cooling aerosols are determinants. Stabilization of global temperature (and ocean acidification for CO2) requires emissions of "long lived greenhouse gases" to be "about zero," including feedbacks. "The feedback … is positive" this century; many large feedback sources tend to be self- and inter-reinforcing. Only timely total conversion of all fossil fuel power to clean, virtually zero-carbon renewable power can achieve virtual zero carbon emissions. This results in multiple, increasing benefits for the entire world population of today's and all future generations, as laid out here. Conversions of methane- and nitrous oxide-emitting sources have large benefits. Without timely conversion to virtual zero emissions, the global climate and ocean disruptions are predicted to become progressively more severe and practically irreversible. "Continued emission of greenhouse gases will increase the likelihood of severe, pervasive and irreversible impacts for people and ecosystems." Crop yields in all main food-producing regions are projected to decline progressively with rising temperature (as proxy to multiple adverse effects) (AR5). Ocean heating, acidification, and de-oxygenation are projected to increase under all scenarios, as is species extinction. The legacy for humanity depends on reducing long-lived global emissions fast enough to virtual zero. Today's surface warming with unprecedented and accelerating atmospheric GHG concentrations requires an immediate response. The only IPCC scenario to possibly meet this and not exceed 2ºC by and after 2100 is the best-case RCP2.6, which requires CO2 eq. emissions to peak right away and decline at the latest by 2020.

  1. Validation and Inter-Comparison of Limb Sounding Profiles from MRO/MCS and MGS/TES

    NASA Astrophysics Data System (ADS)

    Shirley, J. H.; McConnochie, T. M.; Kass, D. M.; Kleinböhl, A.; Schofield, J. T.; Heavens, N. G.; McCleese, D. J.; Benson, J.; Hinson, D. P.; Bandfield, J. L.

    2014-07-01

    Nighttime atmospheric temperatures in northern middle latitudes during Mars' aphelion season obtained by MGS/TES and MRO/MCS are compared with MGS radio science results. Profile mean Δ Ts of <= 2 K demonstrate consistency of retrieved temperatures.

  2. An Experimental Investigation Into the Temperature Profile of a Compliant Foil Air Bearing

    NASA Technical Reports Server (NTRS)

    Radil, Kevin; Zeszotek, Michelle

    2004-01-01

    A series of tests was performed to determine the internal temperature profile in a compliant bump-type foil journal air bearing operating at room temperature under various speeds and load conditions. The temperature profile was collected by instrumenting a foil bearing with nine, type K thermocouples arranged in the center and along the bearing s edges in order to measure local temperatures and estimate thermal gradients in the axial and circumferential directions. To facilitate the measurement of maximum temperatures from viscous shearing in the air film, the thermocouples were tack welded to the backside of the bumps that were in direct contact with the top foil. The mating journal was coated with a high temperature solid lubricant that, together with the bearing, underwent high temperature start-stop cycles to produce a smooth, steady-state run-in surface. Tests were conducted at speeds from 20 to 50 krpm and loads ranging from 9 to 222 N. The results indicate that, over the conditions tested, both journal rotational speed and radial load are responsible for heat generation with speed playing a more significant role in the magnitude of the temperatures. The temperature distribution was nearly symmetric about the bearing center at 20 and 30 krpm but became slightly skewed toward one side at 40 and 50 krpm. Surprisingly, the maximum temperatures did not occur at the bearing edge where the minimum film thickness is expected but rather in the middle of the bearing where analytical investigations have predicted the air film to be much thicker. Thermal gradients were common during testing and were strongest in the axial direction from the middle of the bearing to its edges, reaching 3.78 8C/mm. The temperature profile indicated the circumferential thermal gradients were negligible.

  3. Multi-Dimensional, Non-Pyrolyzing Ablation Test Problems

    NASA Technical Reports Server (NTRS)

    Risch, Tim; Kostyk, Chris

    2016-01-01

    Non-pyrolyzingcarbonaceous materials represent a class of candidate material for hypersonic vehicle components providing both structural and thermal protection system capabilities. Two problems relevant to this technology are presented. The first considers the one-dimensional ablation of a carbon material subject to convective heating. The second considers two-dimensional conduction in a rectangular block subject to radiative heating. Surface thermochemistry for both problems includes finite-rate surface kinetics at low temperatures, diffusion limited ablation at intermediate temperatures, and vaporization at high temperatures. The first problem requires the solution of both the steady-state thermal profile with respect to the ablating surface and the transient thermal history for a one-dimensional ablating planar slab with temperature-dependent material properties. The slab front face is convectively heated and also reradiates to a room temperature environment. The back face is adiabatic. The steady-state temperature profile and steady-state mass loss rate should be predicted. Time-dependent front and back face temperature, surface recession and recession rate along with the final temperature profile should be predicted for the time-dependent solution. The second problem requires the solution for the transient temperature history for an ablating, two-dimensional rectangular solid with anisotropic, temperature-dependent thermal properties. The front face is radiatively heated, convectively cooled, and also reradiates to a room temperature environment. The back face and sidewalls are adiabatic. The solution should include the following 9 items: final surface recession profile, time-dependent temperature history of both the front face and back face at both the centerline and sidewall, as well as the time-dependent surface recession and recession rate on the front face at both the centerline and sidewall. The results of the problems from all submitters will be collected, summarized, and presented at a later conference.

  4. The generalization of upper atmospheric wind and temperature based on the Voigt line shape profile.

    PubMed

    Zhang, Chunmin; He, Jian

    2006-12-25

    The principle of probing the upper atmospheric wind field, which is the Voigt profile spectral line shape, is presented for the first time. By the Fourier Transform of Voigt profile, with the Imaging Spectroscope and the Doppler effect of electromagnetic wave, the distribution and calculation formulae of the velocity field, temperature field, and pressure field of the upper atmosphere wind field are given. The probed source is the two major aurora emission lines originated from the metastable O(1S) and O(1D) at 557.7nm and 630.0nm. From computer simulation and error analysis, the Voigt profile, which is the correlation of the Gaussian profile and Lorentzian profile, is closest to the actual airglow emission lines.

  5. Evaluation and optimization of lidar temperature analysis algorithms using simulated data

    NASA Technical Reports Server (NTRS)

    Leblanc, Thierry; McDermid, I. Stuart; Hauchecorne, Alain; Keckhut, Philippe

    1998-01-01

    The middle atmosphere (20 to 90 km altitude) ha received increasing interest from the scientific community during the last decades, especially since such problems as polar ozone depletion and climatic change have become so important. Temperature profiles have been obtained in this region using a variety of satellite-, rocket-, and balloon-borne instruments as well as some ground-based systems. One of the more promising of these instruments, especially for long-term high resolution measurements, is the lidar. Measurements of laser radiation Rayleigh backscattered, or Raman scattered, by atmospheric air molecules can be used to determine the relative air density profile and subsequently the temperature profile if it is assumed that the atmosphere is in hydrostatic equilibrium and follows the ideal gas law. The high vertical and spatial resolution make the lidar a well adapted instrument for the study of many middle atmospheric processes and phenomena as well as for the evaluation and validation of temperature measurements from satellites, such as the Upper Atmosphere Research Satellite (UARS). In the Network for Detection of Stratospheric Change (NDSC) lidar is the core instrument for measuring middle atmosphere temperature profiles. Using the best lidar analysis algorithm possible is therefore of crucial importance. In this work, the JPL and CNRS/SA lidar analysis software were evaluated. The results of this evaluation allowed the programs to be corrected and optimized and new production software versions were produced. First, a brief description of the lidar technique and the method used to simulate lidar raw-data profiles from a given temperature profile is presented. Evaluation and optimization of the JPL and CNRS/SA algorithms are then discussed.

  6. New Thermal Taste Actuation Technology for Future Multisensory Virtual Reality and Internet.

    PubMed

    Karunanayaka, Kasun; Johari, Nurafiqah; Hariri, Surina; Camelia, Hanis; Bielawski, Kevin Stanley; Cheok, Adrian David

    2018-04-01

    Today's virtual reality (VR) applications such as gaming, multisensory entertainment, remote dining, and online shopping are mainly based on audio, visual, and touch interactions between humans and virtual worlds. Integrating the sense of taste into VR is difficult since humans are dependent on chemical-based taste delivery systems. This paper presents the 'Thermal Taste Machine', a new digital taste actuation technology that can effectively produce and modify thermal taste sensations on the tongue. It modifies the temperature of the surface of the tongue within a short period of time (from 25°C to 40 °C while heating, and from 25°C to 10 °C while cooling). We tested this device on human subjects and described the experience of thermal taste using 20 known (taste and non-taste) sensations. Our results suggested that rapidly heating the tongue produces sweetness, fatty/oiliness, electric taste, warmness, and reduces the sensibility for metallic taste. Similarly, cooling the tongue produced mint taste, pleasantness, and coldness. By conducting another user study on the perceived sweetness of sucrose solutions after the thermal stimulation, we found that heating the tongue significantly enhances the intensity of sweetness for both thermal tasters and non-thermal tasters. Also, we found that faster temperature rises on the tongue produce more intense sweet sensations for thermal tasters. This technology will be useful in two ways: First, it can produce taste sensations without using chemicals for the individuals who are sensitive to thermal taste. Second, the temperature rise of the device can be used as a way to enhance the intensity of sweetness. We believe that this technology can be used to digitally produce and enhance taste sensations in future virtual reality applications. The key novelties of this paper are as follows: 1. Development of a thermal taste actuation technology for stimulating the human taste receptors, 2. Characterization of the thermal taste produced by the device using taste-related sensations and non-taste related sensations, 3. Research on enhancing the intensity for sucrose solutions using thermal stimulation, 4. Research on how different speeds of heating affect the intensity of sweetness produced by thermal stimulation.

  7. Boundary layer temperature measurements of a noctual urban boundary layer

    NASA Astrophysics Data System (ADS)

    Holloway, Simon; Ricketts, Hugo; Vaughan, Geraint

    2018-04-01

    A low-power lidar system based in Manchester, United Kingdom has been developed to measure temperature profiles in the nocturnal urban boundary layer. The lidar transmitter uses a 355nm diode-pumped solid state Nd:YAG laser and two narrow-band interference filters in the receiver filter out rotational Raman lines that are dependent on temperature. The spectral response of the lidar is calibrated using a monochromator. Temperature profiles measured by the system are calibrated by comparison to co-located radiosondes.

  8. Comparison of modeled and experimental PV array temperature profiles for accurate interpretation of module performance and degradation

    NASA Astrophysics Data System (ADS)

    Elwood, Teri; Simmons-Potter, Kelly

    2017-08-01

    Quantification of the effect of temperature on photovoltaic (PV) module efficiency is vital to the correct interpretation of PV module performance under varied environmental conditions. However, previous work has demonstrated that PV module arrays in the field are subject to significant location-based temperature variations associated with, for example, local heating/cooling and array edge effects. Such thermal non-uniformity can potentially lead to under-prediction or over-prediction of PV array performance due to an incorrect interpretation of individual module temperature de-rating. In the current work, a simulated method for modeling the thermal profile of an extended PV array has been investigated through extensive computational modeling utilizing ANSYS, a high-performance computational fluid dynamics (CFD) software tool. Using the local wind speed as an input, simulations were run to determine the velocity at particular points along modular strings corresponding to the locations of temperature sensors along strings in the field. The point velocities were utilized along with laminar flow theories in order to calculate Nusselt's number for each point. These calculations produced a heat flux profile which, when combined with local thermal and solar radiation profiles, were used as inputs in an ANSYS Thermal Transient model that generated a solar string operating temperature profile. A comparison of the data collected during field testing, and the data fabricated by ANSYS simulations, will be discussed in order to authenticate the accuracy of the model.

  9. Simulated X-ray galaxy clusters at the virial radius: Slopes of the gas density, temperature and surface brightness profiles

    NASA Astrophysics Data System (ADS)

    Roncarelli, M.; Ettori, S.; Dolag, K.; Moscardini, L.; Borgani, S.; Murante, G.

    2006-12-01

    Using a set of hydrodynamical simulations of nine galaxy clusters with masses in the range 1.5 × 1014 < Mvir < 3.4 × 1015Msolar, we have studied the density, temperature and X-ray surface brightness profiles of the intracluster medium in the regions around the virial radius. We have analysed the profiles in the radial range well above the cluster core, the physics of which are still unclear and matter of tension between simulated and observed properties, and up to the virial radius and beyond, where present observations are unable to provide any constraints. We have modelled the radial profiles between 0.3R200 and 3R200 with power laws with one index, two indexes and a rolling index. The simulated temperature and [0.5-2] keV surface brightness profiles well reproduce the observed behaviours outside the core. The shape of all these profiles in the radial range considered depends mainly on the activity of the gravitational collapse, with no significant difference among models including extraphysics. The profiles steepen in the outskirts, with the slope of the power-law fit that changes from -2.5 to -3.4 in the gas density, from -0.5 to -1.8 in the gas temperature and from -3.5 to -5.0 in the X-ray soft surface brightness. We predict that the gas density, temperature and [0.5-2] keV surface brightness values at R200 are, on average, 0.05, 0.60, 0.008 times the measured values at 0.3R200. At 2R200, these values decrease by an order of magnitude in the gas density and surface brightness, by a factor of 2 in the temperature, putting stringent limits on the detectable properties of the intracluster-medium (ICM) in the virial regions.

  10. Identifying web usage behavior of bank customers

    NASA Astrophysics Data System (ADS)

    Araya, Sandro; Silva, Mariano; Weber, Richard

    2002-03-01

    The bank Banco Credito e Inversiones (BCI) started its virtual bank in 1996 and its registered customers perform currently more than 10,000 Internet transactions daily, which typically cause les than 10% of traditional transaction costs. Since most of the customers are still not registered for online banking, one of the goals of the virtual bank is to increase then umber of registered customers. Objective of the presented work was to identify customers who are likely to perform online banking but still do not use this medium for their transactions. This objective has been reached by determining profiles of registered customers who perform many transactions online. Based on these profiles the bank's Data Warehouse is explored for twins of these heavy users that are still not registered for online banking. We applied clustering in order to group the registered customers into five classes. One of these classes contained almost 30% of all registered customers and could clearly be identified as class of heavy users. Next a neural network assigned online customers to the previously found five classes. Applying the network trained on online customers to all the bank customers identified twins of heavy users that, however had not performed online transactions so far. A mailing to these candidates informing about the advantages of online banking doubled the number of registrations compared to previous campaigns.

  11. Measuring centimeter-resolution air temperature profiles above land and water using fiber-optic Distributed Temperature Sensing

    NASA Astrophysics Data System (ADS)

    Sigmund, Armin; Pfister, Lena; Olesch, Johannes; Thomas, Christoph K.

    2016-04-01

    The precise determination of near-surface air temperature profiles is of special importance for the characterization of airflows (e.g. cold air) and the quantification of sensible heat fluxes according to the flux-gradient similarity approach. In contrast to conventional multi-sensor techniques, measuring temperature profiles using fiber-optic Distributed Temperature Sensing (DTS) provides thousands of measurements referenced to a single calibration standard at much reduced costs. The aim of this work was to enhance the vertical resolution of Raman scatter DTS measurements up to the centimeter-scale using a novel approach for atmospheric applications: the optical fiber was helically coiled around a meshed fabric. In addition to testing the new fiber geometry, we quantified the measurement uncertainty and demonstrated the benefits of the enhanced-resolution profiles. The fiber-optic cable was coiled around a hollow column consisting of white reinforcing fabric supported by plexiglass rings every meter. Data from two columns of this type were collected for 47 days to measure air temperature vertically over 3.0 and 5.1 m over a gently inclined meadow and over and in a small lake, respectively. Both profiles had a vertical resolution of 1 cm in the lower section near the surface and 5 cm in the upper section with an along-fiber instrument-specific averaging of 1.0 m and a temporal resolution of 30 s. Measurement uncertainties, especially from conduction between reinforcing fabric and fiber-optic cable, were estimated by modeling the fiber temperature via a detailed energy balance approach. Air temperature, wind velocity and radiation components were needed as input data and measured separately. The temperature profiles revealed valuable details, especially in the lowest 1 m above surface. This was best demonstrated for nighttime observations when artefacts due to solar heating did not occur. For example, the dynamics of a cold air layer was detected in a clear night with weak wind. In the same night temperature gradients up to 30 K m-1 were determined above the meadow. The water was up to 13 K warmer than the air in this night resulting in a sharp and strong temperature decrease at the water surface and a moderate decrease with gradients up to -9 K m-1 in the air above. The plexiglass rings caused some obvious artefacts and affected data was removed and replaced by linear interpolation. According to the uncertainty estimation performed to date, conduction between fabric and fiber increased fiber temperatures by approximately 0.005 K at 2 m height on a sunny day with weak wind. This effect was deemed negligible as it reflected less than 1 % of the total heating compared to that in the air. The maximum absolute error was approximately 0.9 K at 2 m height on the same day. Ongoing work will demonstrate potential benefits of the enhanced-resolution profiles by quantitatively comparing measured and interpolated temperature profiles with varying resolution (as well as sensible heat fluxes computed according to flux-gradient-similarity).

  12. Multiple neutral density measurements in the lower thermosphere with cold-cathode ionization gauges

    NASA Astrophysics Data System (ADS)

    Lehmacher, G. A.; Gaulden, T. M.; Larsen, M. F.; Craven, J. D.

    2013-01-01

    Cold-cathode ionization gauges were used for rocket-borne measurements of total neutral density and temperature in the aurorally forced lower thermosphere between 90 and 200 km. A commercial gauge was adapted as a low-cost instrument with a spherical antechamber for measurements in molecular flow conditions. Three roll-stabilized payloads on different trajectories each carried two instruments for measurements near the ram flow direction along the respective upleg and downleg segments of a flight path, and six density profiles were obtained within a period of 22 min covering spatial separations up to 200 km. The density profiles were integrated below 125 km to yield temperatures. The mean temperature structure was similar for all six profiles with two mesopause minima near 110 and 101 km, however, for the downleg profiles, the upper minimum was warmer and the lower minimum was colder by 20-30 K indicating significant variability over horizontal scales of 100-200 km. The upper temperature minimum coincided with maximum horizontal winds speeds, exceeding 170 m/s.

  13. Vertical temperature and density patterns in the Arctic mesosphere analyzed as gravity waves

    NASA Technical Reports Server (NTRS)

    Eberstein, I. J.; Theon, J. S.

    1975-01-01

    Rocket soundings conducted from high latitude sites in the Arctic mesosphere are described. Temperature and wind profiles and one density profile were observed independently to obtain the thermodynamic structure, the wind structure, and their interdependence in the mesosphere. Temperature profiles from all soundings were averaged, and a smooth curve (or series of smooth curves) drawn through the points. A hydrostatic atmosphere based on the average, measured temperature profile was computed, and deviations from the mean atmosphere were analyzed in terms of gravity wave theory. The vertical wavelengths of the deviations were 10-20 km, and the wave amplitudes slowly increased with height. The experimental data were matched by calculated gravity waves having a period of 15-20 minutes and a horizontal wavelength of 60-80 km. The wind measurements are consistent with the thermodynamic measurements. The results also suggest that gravity waves travel from East to West with a horizontal phase velocity of approximately 60 m sec-1.

  14. High Spectral Resolution Lidar for atmospheric temperature profiling.

    NASA Astrophysics Data System (ADS)

    Razenkov, I.; Eloranta, E. W.

    2017-12-01

    The High Spectral Resolution Lidar (HSRL) designed at the University of Wisconsin-Madison is equipped with two iodine absorption filters with different line widths (1.8 GHz and 2.85 GHz). The filters are implemented to discriminate between Mie and Rayleigh backscattering and to resolve temperature sensitive changes in Rayleigh spectrum for atmospheric temperature profile measurements. This measurement capability makes the instrument intrinsically and absolutely calibrated. HSRL has a shared transmitter-receiver telescope and operates in the eye-safe mode with the product of laser average power and telescope aperture less than 0.025 𝑊𝑚2 at 532 nm. With this low-power prototype instrument we have achieved temperature profile measurements extending above tropopause with a time resolution of several hours. Further instrument optimizations will reduce systematic measurement errors and will improve a signal-to-noise ratio providing temperature data comparable to a standard radiosonde with higher time resolution.

  15. A methodology for using borehole temperature-depth profiles under ambient, single and cross-borehole pumping conditions to estimate fracture hydraulic properties

    NASA Astrophysics Data System (ADS)

    Klepikova, Maria V.; Le Borgne, Tanguy; Bour, Olivier; Davy, Philippe

    2011-09-01

    SummaryTemperature profiles in the subsurface are known to be sensitive to groundwater flow. Here we show that they are also strongly related to vertical flow in the boreholes themselves. Based on a numerical model of flow and heat transfer at the borehole scale, we propose a method to invert temperature measurements to derive borehole flow velocities. This method is applied to an experimental site in fractured crystalline rocks. Vertical flow velocities deduced from the inversion of temperature measurements are compared with direct heat-pulse flowmeter measurements showing a good agreement over two orders of magnitudes. Applying this methodology under ambient, single and cross-borehole pumping conditions allows us to estimate fracture hydraulic head and local transmissivity, as well as inter-borehole fracture connectivity. Thus, these results provide new insights on how to include temperature profiles in inverse problems for estimating hydraulic fracture properties.

  16. Temperature-Dependent Kinetic Prediction for Reactions Described by Isothermal Mathematics

    DOE PAGES

    Dinh, L. N.; Sun, T. C.; McLean, W.

    2016-09-12

    Most kinetic models are expressed in isothermal mathematics. In addition, this may lead unaware scientists either to the misconception that classical isothermal kinetic models cannot be used for any chemical process in an environment with a time-dependent temperature profile or, even worse, to a misuse of them. In reality, classical isothermal models can be employed to make kinetic predictions for reactions in environments with time-dependent temperature profiles, provided that there is a continuity/conservation in the reaction extent at every temperature–time step. In this article, fundamental analyses, illustrations, guiding tables, and examples are given to help the interested readers using eithermore » conventional isothermal reacted fraction curves or rate equations to make proper kinetic predictions for chemical reactions in environments with temperature profiles that vary, even arbitrarily, with time simply by the requirement of continuity/conservation of reaction extent whenever there is an external temperature change.« less

  17. The effect of virtual bidding on forward premiums in the New York wholesale energy market

    NASA Astrophysics Data System (ADS)

    Knudsen, Andrew D.

    In many parts of the United States, the power industry has been deregulated and replaced with regional wholesale energy markets, where utilities purchase electricity from generators at competitive market rates for subsequent distribution to customers. Numerous studies have shown that in each of these markets, the price of energy purchased in the Day Ahead (futures) market exceeds the price in the Real Time (spot) market on average. The existence of this "forward premium" is evidence of market inefficiency and may indicate participants' aversion to risk in the Real Time market or the exercise of market power by generators. To address this inefficiency, the New York Independent System Operator introduced a virtual bidding system within its wholesale market, which permitted participants to engage in purely financial transactions and hedge their exposure to risk. The new policy was expected to promote price convergence by allowing bidders to arbitrage expected differences between Day Ahead and Real Time prices. This study examines whether the presence of virtual bidding was associated with a change in the mean value and magnitude of forward premiums in the NYISO energy market. The study applies a GARCH model to hourly pricing data from 2001 to 2009, controlling for temperature and economic activity. The results indicate that prior to 2005, virtual bidding was associated with significantly lower and less volatile forward premiums in New York's five most congested zones but with increased premiums in the remaining less congested zones. However, when the entire period from 2001 to 2009 is examined, the results suggest that prices have become significantly more divergent in the presence of virtual bidding. Closer examination of the data reveals a dramatic increase in forward premium volatility across all zones beginning in 2005 that is not accounted for by temperature or economic activity and may have biased the results. This study attempts to account for this unexplained shift in price behavior by limiting the analysis to off-peak hours and by substituting an adjusted measure of forward premium, but neither approach yields results consistent with the pre-2005 effects. Further study is needed to identify the potential causes of the sudden increase in forward premium volatility and isolate the effect of virtual bidding on NYISO price convergence.

  18. A virtual laboratory for the simulation of sustainable energy systems in a low energy building: A case study

    NASA Astrophysics Data System (ADS)

    Breen, M.; O'Donovan, A.; Murphy, M. D.; Delaney, F.; Hill, M.; Sullivan, P. D. O.

    2016-03-01

    The aim of this paper was to develop a virtual laboratory simulation platform of the National Building Retrofit Test-bed at the Cork Institute of Technology, Ireland. The building in question is a low-energy retrofit which is provided with electricity by renewable systems including photovoltaics and wind. It can be thought of as a living laboratory, as a number of internal and external building factors are recorded at regular intervals during human occupation. The analysis carried out in this paper demonstrated that, for the period from April to September 2015, the electricity provided by the renewable systems did not consistently match the building’s electricity requirements due to differing load profiles. It was concluded that the use of load shifting techniques may help to increase the percentage of renewable energy utilisation.

  19. Surgery-first approach using a three-dimensional virtual setup and surgical simulation for skeletal Class III correction

    PubMed Central

    Im, Joon; Kang, Sang Hoon; Lee, Ji Yeon; Kim, Moon Key

    2014-01-01

    A 19-year-old woman presented to our dental clinic with anterior crossbite and mandibular prognathism. She had a concave profile, long face, and Angle Class III molar relationship. She showed disharmony in the crowding of the maxillomandibular dentition and midline deviation. The diagnosis and treatment plan were established by a three-dimensional (3D) virtual setup and 3D surgical simulation, and a surgical wafer was produced using the stereolithography technique. No presurgical orthodontic treatment was performed. Using the surgery-first approach, Le Fort I maxillary osteotomy and mandibular bilateral intraoral vertical ramus osteotomy setback were carried out. Treatment was completed with postorthodontic treatment. Thus, symmetrical and balanced facial soft tissue and facial form as well as stabilized and well-balanced occlusion were achieved. PMID:25473649

  20. Project-focused activity and knowledge tracker: a unified data analysis, collaboration, and workflow tool for medicinal chemistry project teams.

    PubMed

    Brodney, Marian D; Brosius, Arthur D; Gregory, Tracy; Heck, Steven D; Klug-McLeod, Jacquelyn L; Poss, Christopher S

    2009-12-01

    Advances in the field of drug discovery have brought an explosion in the quantity of data available to medicinal chemists and other project team members. New strategies and systems are needed to help these scientists to efficiently gather, organize, analyze, annotate, and share data about potential new drug molecules of interest to their project teams. Herein we describe a suite of integrated services and end-user applications that facilitate these activities throughout the medicinal chemistry design cycle. The Automated Data Presentation (ADP) and Virtual Compound Profiler (VCP) processes automate the gathering, organization, and storage of real and virtual molecules, respectively, and associated data. The Project-Focused Activity and Knowledge Tracker (PFAKT) provides a unified data analysis and collaboration environment, enhancing decision-making, improving team communication, and increasing efficiency.

  1. Bayesian Models Leveraging Bioactivity and Cytotoxicity Information for Drug Discovery

    PubMed Central

    Ekins, Sean; Reynolds, Robert C.; Kim, Hiyun; Koo, Mi-Sun; Ekonomidis, Marilyn; Talaue, Meliza; Paget, Steve D.; Woolhiser, Lisa K.; Lenaerts, Anne J.; Bunin, Barry A.; Connell, Nancy; Freundlich, Joel S.

    2013-01-01

    SUMMARY Identification of unique leads represents a significant challenge in drug discovery. This hurdle is magnified in neglected diseases such as tuberculosis. We have leveraged public high-throughput screening (HTS) data, to experimentally validate virtual screening approach employing Bayesian models built with bioactivity information (single-event model) as well as bioactivity and cytotoxicity information (dual-event model). We virtually screen a commercial library and experimentally confirm actives with hit rates exceeding typical HTS results by 1-2 orders of magnitude. The first dual-event Bayesian model identified compounds with antitubercular whole-cell activity and low mammalian cell cytotoxicity from a published set of antimalarials. The most potent hit exhibits the in vitro activity and in vitro/in vivo safety profile of a drug lead. These Bayesian models offer significant economies in time and cost to drug discovery. PMID:23521795

  2. Position specific interaction dependent scoring technique for virtual screening based on weighted protein--ligand interaction fingerprint profiles.

    PubMed

    Nandigam, Ravi K; Kim, Sangtae; Singh, Juswinder; Chuaqui, Claudio

    2009-05-01

    The desire to exploit structural information to aid structure based design and virtual screening led to the development of the interaction fingerprint for analyzing, mining, and filtering the binding patterns underlying the complex 3D data. In this paper we introduce a new approach, weighted SIFt (or w-SIFt), extending the concept of SIFt to capture the relative importance of different binding interactions. The methodology presented here for determining the weights in w-SIFt involves utilizing a dimensionality reduction technique for eliminating linear redundancies in the data followed by a stochastic optimization. We find that the relative weights of the fingerprint bits provide insight into what interactions are critical in determining inhibitor potency. Moreover, the weighted interaction fingerprint can serve as an interpretable position dependent scoring function for ligand protein interactions.

  3. Effect of Internal Solitary Waves on Underwater Acoustic Propagation

    DTIC Science & Technology

    2010-01-01

    and 760 m from an expendable bathyther- mograph and one temperature profile below 760 m from the Navy’s Gen- eralized Digital Environment Model ( GDEM ...To calculate sound speed, the GDEM (average of July and August) salinity profile (nearest to CMB) was used. The sound speeds calculated from the GDEM ...from the GDEM sa- linity profile and 424 temperature pro- files generated the range-dependent SSPs (Figure 6). Comparison of the acoustic propagation

  4. Evapotranspiration and microclimate at a low-level radioactive-waste disposal site in northwestern Illinois

    USGS Publications Warehouse

    Healy, R.W.; DeVries, M.P.; Sturrock, Alex M.

    1989-01-01

    From July 1982 through June 1984, a study was made of the evapotranspiration and microclimate at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Vegetation at the site consists of mixed pasture grasses, primarily awnless brome (Bromus inermis) and red clover (Trifoleum pratense). Three methods were used to estimate evapotranspiration: (1) an energy budget with the Bowen ratio, (2) an aerodynamic profile, and (3) a soil-based water budget. For the aerodynamic-profile method, sensible-heat flux was estimated by a profile equation and evapotranspiration was then calculated as the residual in the energy-balance equation. Estimates by the energy-budget and aerodynamic-profile methods were computed from hourly data and then summed by days and months. Yearly estimates (for March through November) by these methods were in close agreement: 648 and 626 millimeters, respectively. Daily estimates reach a maximum of about 6 millimeters. The water-budget method produced only monthly estimates based on weekly or biweekly soil-moisture content measurements. The yearly evapotranspiration estimated by this method (which actually included only the months of April through October) was 655 millimeters. The March-through-November average for the three methods of 657 millimeters was equivalent to 70 percent of total precipitation. Continuous measurements were made of incoming and reflected shortwave radiation, incoming and emitted longwave radiation, net radiation, soil-heat flux, soil temperature, horizontal windspeed, and wet- and dry-bulb air temperature. Windspeed and air temperature were measured at heights of 0.5 and 2.0 meters (and also at 1.0 meter after September 1983). Soilmoisture content of the soil zone was measured with a gamma-attenuation gage. Annual precipitation (938 millimeters) and average temperature (10.8 degrees Celsius) at the Sheffield site were virtually identical to long-term averages from nearby National Weather Service stations. Solar radiation averaged 65 percent of that normally expected under clear skies. Net radiation averaged 70.1 watts per square meter and was highest in July and negative during some winter months. Wind direction varied but was predominately south-southeasterly. Wind speed at the 2-meter height averaged 3.5 meters per second and was slightly higher in winter months than the rest of the year. The amount of water stored within the soil zone was greatest in early spring and least in late summer. Seasonal and diurnal trends of evapotranspiration rates mirrored those of net radiation; July was usually the month with the highest evapotranspiration rate. The ratio of sensible- to latentheat fluxes (commonly called the Bowen ratio) for the 2-year study period was 0.38, as averaged from the three methods. Monthly Bowen ratios fluctuated somewhat but averaged about 0.35 for late spring through summer. In fall, the ratio declined to zero or to slightly negative values. When the ratio was negative, the latent-heat flux was slightly greater than the net radiation because of additional energy supplied by' the cooling soil and air. Evapotranspiration calculated by the three methods averaged 75 percent of potential evapotranspiration, as estimated by the Penman equation. There was no apparent seasonal trend in the relation between actual and potential evapotranspiration rates.

  5. How shorter black carbon lifetime alters its climate effect.

    PubMed

    Hodnebrog, Øivind; Myhre, Gunnar; Samset, Bjørn H

    2014-09-25

    Black carbon (BC), unlike most aerosol types, absorbs solar radiation. However, the quantification of its climate impact is uncertain and presently under debate. Recently, attention has been drawn both to a likely underestimation of global BC emissions in climate models, and an overestimation of BC at high altitudes. Here we show that doubling present day BC emissions in a model simulation, while reducing BC lifetime based on observational evidence, leaves the direct aerosol effect of BC virtually unchanged. Increased emissions, together with increased wet removal that reduces the lifetime, yields modelled BC vertical profiles that are in strongly improved agreement with recent aircraft observations. Furthermore, we explore the consequences of an altered BC profile in a global circulation model, and show that both the vertical profile of BC and rapid climate adjustments need to be taken into account in order to assess the total climate impact of BC.

  6. Water Plume Temperature Measurements by an Unmanned Aerial System (UAS)

    PubMed Central

    DeMario, Anthony; Lopez, Pete; Plewka, Eli; Wix, Ryan; Xia, Hai; Zamora, Emily; Gessler, Dan; Yalin, Azer P.

    2017-01-01

    We report on the development and testing of a proof of principle water temperature measurement system deployed on an unmanned aerial system (UAS), for field measurements of thermal discharges into water. The primary elements of the system include a quad-copter UAS to which has been integrated, for the first time, both a thermal imaging infrared (IR) camera and an immersible probe that can be dipped below the water surface to obtain vertical water temperature profiles. The IR camera is used to take images of the overall water surface to geo-locate the plume, while the immersible probe provides quantitative temperature depth profiles at specific locations. The full system has been tested including the navigation of the UAS, its ability to safely carry the sensor payload, and the performance of both the IR camera and the temperature probe. Finally, the UAS sensor system was successfully deployed in a pilot field study at a coal burning power plant, and obtained images and temperature profiles of the thermal effluent. PMID:28178215

  7. Water Plume Temperature Measurements by an Unmanned Aerial System (UAS).

    PubMed

    DeMario, Anthony; Lopez, Pete; Plewka, Eli; Wix, Ryan; Xia, Hai; Zamora, Emily; Gessler, Dan; Yalin, Azer P

    2017-02-07

    We report on the development and testing of a proof of principle water temperature measurement system deployed on an unmanned aerial system (UAS), for field measurements of thermal discharges into water. The primary elements of the system include a quad-copter UAS to which has been integrated, for the first time, both a thermal imaging infrared (IR) camera and an immersible probe that can be dipped below the water surface to obtain vertical water temperature profiles. The IR camera is used to take images of the overall water surface to geo-locate the plume, while the immersible probe provides quantitative temperature depth profiles at specific locations. The full system has been tested including the navigation of the UAS, its ability to safely carry the sensor payload, and the performance of both the IR camera and the temperature probe. Finally, the UAS sensor system was successfully deployed in a pilot field study at a coal burning power plant, and obtained images and temperature profiles of the thermal effluent.

  8. A simple algorithm for beam profile diagnostics using a thermographic camera

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

    Katagiri, Ken; Hojo, Satoru; Honma, Toshihiro

    2014-03-15

    A new algorithm for digital image processing apparatuses is developed to evaluate profiles of high-intensity DC beams from temperature images of irradiated thin foils. Numerical analyses are performed to examine the reliability of the algorithm. To simulate the temperature images acquired by a thermographic camera, temperature distributions are numerically calculated for 20 MeV proton beams with different parameters. Noise in the temperature images which is added by the camera sensor is also simulated to account for its effect. Using the algorithm, beam profiles are evaluated from the simulated temperature images and compared with exact solutions. We find that niobium ismore » an appropriate material for the thin foil used in the diagnostic system. We also confirm that the algorithm is adaptable over a wide beam current range of 0.11–214 μA, even when employing a general-purpose thermographic camera with rather high noise (ΔT{sub NETD} ≃ 0.3 K; NETD: noise equivalent temperature difference)« less

  9. Remote Water Temperature Measurements Based on Brillouin Scattering with a Frequency Doubled Pulsed Yb:doped Fiber Amplifier

    PubMed Central

    Schorstein, Kai; Popescu, Alexandru; Göbel, Marco; Walther, Thomas

    2008-01-01

    Temperature profiles of the ocean are of interest for weather forecasts, climate studies and oceanography in general. Currently, mostly in situ techniques such as fixed buoys or bathythermographs deliver oceanic temperature profiles. A LIDAR method based on Brillouin scattering is an attractive alternative for remote sensing of such water temperature profiles. It makes it possible to deliver cost-effective on-line data covering an extended region of the ocean. The temperature measurement is based on spontaneous Brillouin scattering in water. In this contribution, we present the first water temperature measurements using a Yb:doped pulsed fiber amplifier. The fiber amplifier is a custom designed device which can be operated in a vibrational environment while emitting narrow bandwidth laser pulses. The device shows promising performance and demonstrates the feasibility of this approach. Furthermore, the current status of the receiver is briefly discussed; it is based on an excited state Faraday anomalous dispersion optical filter. PMID:27873842

  10. Temperature and pressure effects on capacitance probe cryogenic liquid level measurement accuracy

    NASA Technical Reports Server (NTRS)

    Edwards, Lawrence G.; Haberbusch, Mark

    1993-01-01

    The inaccuracies of liquid nitrogen and liquid hydrogen level measurements by use of a coaxial capacitance probe were investigated as a function of fluid temperatures and pressures. Significant liquid level measurement errors were found to occur due to the changes in the fluids dielectric constants which develop over the operating temperature and pressure ranges of the cryogenic storage tanks. The level measurement inaccuracies can be reduced by using fluid dielectric correction factors based on measured fluid temperatures and pressures. The errors in the corrected liquid level measurements were estimated based on the reported calibration errors of the temperature and pressure measurement systems. Experimental liquid nitrogen (LN2) and liquid hydrogen (LH2) level measurements were obtained using the calibrated capacitance probe equations and also by the dielectric constant correction factor method. The liquid levels obtained by the capacitance probe for the two methods were compared with the liquid level estimated from the fluid temperature profiles. Results show that the dielectric constant corrected liquid levels agreed within 0.5 percent of the temperature profile estimated liquid level. The uncorrected dielectric constant capacitance liquid level measurements deviated from the temperature profile level by more than 5 percent. This paper identifies the magnitude of liquid level measurement error that can occur for LN2 and LH2 fluids due to temperature and pressure effects on the dielectric constants over the tank storage conditions from 5 to 40 psia. A method of reducing the level measurement errors by using dielectric constant correction factors based on fluid temperature and pressure measurements is derived. The improved accuracy by use of the correction factors is experimentally verified by comparing liquid levels derived from fluid temperature profiles.

  11. Synthetic temperature profiles derived from Geosat altimetry: Comparison with air-dropped expendable bathythermograph profiles

    NASA Astrophysics Data System (ADS)

    Carnes, Michael R.; Mitchell, Jim L.; de Witt, P. Webb

    1990-10-01

    Synthetic temperature profiles are computed from altimeter-derived sea surface heights in the Gulf Stream region. The required relationships between surface height (dynamic height at the surface relative to 1000 dbar) and subsurface temperature are provided from regression relationships between dynamic height and amplitudes of empirical orthogonal functions (EOFs) of the vertical structure of temperature derived by de Witt (1987). Relationships were derived for each month of the year from historical temperature and salinity profiles from the region surrounding the Gulf Stream northeast of Cape Hatteras. Sea surface heights are derived using two different geoid estimates, the feature-modeled geoid and the air-dropped expendable bathythermograph (AXBT) geoid, both described by Carnes et al. (1990). The accuracy of the synthetic profiles is assessed by comparison to 21 AXBT profile sections which were taken during three surveys along 12 Geosat ERM ground tracks nearly contemporaneously with Geosat overflights. The primary error statistic considered is the root-mean-square (rms) difference between AXBT and synthetic isotherm depths. The two sources of error are the EOF relationship and the altimeter-derived surface heights. EOF-related and surface height-related errors in synthetic temperature isotherm depth are of comparable magnitude; each translates into about a 60-m rms isotherm depth error, or a combined 80 m to 90 m error for isotherms in the permanent thermocline. EOF-related errors are responsible for the absence of the near-surface warm core of the Gulf Stream and for the reduced volume of Eighteen Degree Water in the upper few hundred meters of (apparently older) cold-core rings in the synthetic profiles. The overall rms difference between surface heights derived from the altimeter and those computed from AXBT profiles is 0.15 dyn m when the feature-modeled geoid is used and 0.19 dyn m when the AXBT geoid is used; the portion attributable to altimeter-derived surface height errors alone is 0.03 dyn m less for each. In most cases, the deeper structure of the Gulf Stream and eddies is reproduced well by vertical sections of synthetic temperature, with largest errors typically in regions of high horizontal gradient such as across rings and the Gulf Stream front.

  12. Using Heat as a Tracer to Estimate Saline Groundwater Fluxes from the Deep Aquifer System to the Shallow Aquifers and the Rio Grande in the Mesilla Basin, New Mexico, USA

    NASA Astrophysics Data System (ADS)

    Pepin, J. D.; Robertson, A.; Ferguson, C.; Burns, E. R.

    2017-12-01

    Heat is used as a tracer to estimate vertical groundwater flow and associated saline fluxes from deep (greater than 1 km) parts of the Mesilla Basin regional aquifer to the Rio Grande. Profiles of temperature with depth below ground surface are used to locate groundwater upflow zones and to estimate associated salinity fluxes. The results of this study will inform understanding of the impact of deep saline groundwater on regional water supplies. The Mesilla Basin in southern New Mexico, Texas, and Chihuahua, Mexico was designated by the U.S. as a priority transboundary aquifer in part because of the presence of the Rio Grande within the basin. Declining water levels, deteriorating water quality in both the aquifer and the river, and increasing use of water resources on both sides of the international border raise concerns about the sustainability of regional water supplies. The Rio Grande chloride concentration increases by about 130% (120 ppm to 280 ppm) as the river traverses the Mesilla Basin. Previous research attributed this reduction in water quality to the upwelling of deep sedimentary brines and geothermal waters within the basin. However, the spatial distribution of these upflow zones and their groundwater flow rates are poorly understood. Temperature profiles from 374 existing boreholes within the Mesilla Basin indicate that temperature-profile shape is affected by heat advection in the basin. Three distinct geothermal upflow zones were identified along regional fault zones in the study area based on the temperature profiles. Groundwater in these zones is considered thermal, having temperatures greater than 50°C at depths of less than 200 m. Identification of upflow-zone profiles combines analysis of temperature profiles, lithologic records, well-completion data, and profile derivatives. The Bredehoeft and Papadopulos (1965) one-dimensional heat-transport analytical solution will be applied to upflow-zone profiles to estimate the corresponding vertical groundwater flow rates. Temperature, heat flow, and salinity maps will be constructed to approximate the areal extents of identified upflow zones. These areal estimates will then be combined with the 1D vertical groundwater flow calculations and salinity data to quantify volumetric salinity fluxes to the shallow aquifer system and Rio Grande.

  13. Study of Mesobeta Basin Flows by Remote Sensing

    NASA Astrophysics Data System (ADS)

    Cuxart, J.; Cunillera, J.; Jiménez, M. A.; Martínez, D.; Molinos, F.; Palau, J. L.

    2012-04-01

    If no well-defined synoptic pressure gradients exist over a basin, flows can develop at a variety of scales, the main generators of circulations being spatial thermal differences. These dynamics are studied for the eastern Ebro basin, at the north-eastern part of the Iberian Peninsula, almost isolated from the surrounding areas by mountain ranges. The main tool for the study is the new RASS-Sodar by Scintec, the WindRASS, which combines sound and radio waves to provide profiles of wind and virtual temperature up to 360 m above the ground in the present configuration. One year of operation shows that low-level jets are found routinely, their maximum speed being at a height below 500 m above ground level. The jets are from a constant direction for several hours over the whole observed column, with rapid transitions between these periods. They allow for efficient heat transport at the basin scale and are good producers of vertical mixing due to the strong wind shear. In summer the irrigated plain has larger thermal contrast with the dry slopes, and the winds are stronger than in winter, when katabatic flows can develop at night and usually radiation fog appears and may last for days.

  14. Crystal Growth Control

    NASA Technical Reports Server (NTRS)

    Duval, Walter M. B.; Batur, Celal; Bennett, Robert J.

    1997-01-01

    We present an innovative design of a vertical transparent multizone furnace which can operate in the temperature range of 25 C to 750 C and deliver thermal gradients of 2 C/cm to 45 C/cm for the commercial applications to crystal growth. The operation of the eight zone furnace is based on a self-tuning temperature control system with a DC power supply for optimal thermal stability. We show that the desired thermal profile over the entire length of the furnace consists of a functional combination of the fundamental thermal profiles for each individual zone obtained by setting the set-point temperature for that zone. The self-tuning system accounts for the zone to zone thermal interactions. The control system operates such that the thermal profile is maintained under thermal load, thus boundary conditions on crystal growth ampoules can be predetermined prior to crystal growth. Temperature profiles for the growth of crystals via directional solidification, vapor transport techniques, and multiple gradient applications are shown to be easily implemented. The unique feature of its transparency and ease of programming thermal profiles make the furnace useful for scientific and commercial applications for the determination of process parameters to optimize crystal growth conditions.

  15. The Design of a Transparent Vertical Multizone Furnace: Application to Thermal Field Tuning and Crystal Growth

    NASA Technical Reports Server (NTRS)

    Duvual, Walter M. B.; Batur, Celal; Bennett, Robert J.

    1998-01-01

    We present an innovative design of a vertical transparent multizone furnace which can operate in the temperature range of 25 C to 750 C and deliver thermal gradients of 2 C/cm to 45 C/cm for the commercial applications to crystal growth. The operation of the eight zone furnace is based on a self-tuning temperature control system with a DC power supply for optimal thermal stability. We show that the desired thermal profile over the entire length of the furnace consists of a functional combination of the fundamental thermal profiles for each individual zone obtained by setting the set-point temperature for that zone. The self-tuning system accounts for the zone to zone thermal interactions. The control system operates such that the thermal profile is maintained under thermal load, thus boundary conditions on crystal growth ampoules can be predetermined prior to crystal growth. Temperature profiles for the growth of crystals via directional solidification, vapor transport techniques, and multiple gradient applications are shown to be easily implemented. The unique feature of its transparency and ease of programming thermal profiles make the furnace useful in scientific and commercial applications for determining the optimized process parameters for crystal growth.

  16. Analyzed DTS Data, Guelph, ON Canada

    DOE Data Explorer

    Coleman, Thomas

    2015-07-01

    Analyzed DTS datasets from active heat injection experiments in Guelph, ON Canada is included. A .pdf file of images including borehole temperature distributions, temperature difference distributions, temperature profiles, and flow interpretations is included as the primary analyzed dataset. Analyzed data used to create the .pdf images are included as a matlab data file that contains the following 5 types of data: 1) Borehole Temperature (matrix of temperature data collected in the borehole), 2) Borehole Temperature Difference (matrix of temperature difference above ambient for each test), 3) Borehole Time (time in both min and sec since the start of a DTS test), 4) Borehole Depth (channel depth locations for the DTS measurements), 5) Temperature Profiles (ambient, active, active off early time, active off late time, and injection).

  17. BELINDA: Broadband Emission Lidar with Narrowband Determination of Absorption. A new concept for measuring water vapor and temperature profiles

    NASA Technical Reports Server (NTRS)

    Theopold, F. A.; Weitkamp, C.; Michaelis, W.

    1992-01-01

    We present a new concept for differential absorption lidar measurements of water vapor and temperature profiles. The idea is to use one broadband emission laser and a narrowband filter system for separation of the 'online' and 'offline' return signals. It is shown that BELINDA offers improvements as to laser emission shape and stability requirements, background suppression, and last and most important a significant reduction of the influence of Rayleigh scattering. A suitably designed system based on this concept is presented, capable of measuring water vapor or temperature profiles throughout the planetary boundary layer.

  18. Recent climate variations in Chile: constraints from borehole temperature profiles

    NASA Astrophysics Data System (ADS)

    Pickler, Carolyne; Gurza Fausto, Edmundo; Beltrami, Hugo; Mareschal, Jean-Claude; Suárez, Francisco; Chacon-Oecklers, Arlette; Blin, Nicole; Cortés Calderón, Maria Teresa; Montenegro, Alvaro; Harris, Rob; Tassara, Andres

    2018-04-01

    We have compiled, collected, and analyzed 31 temperature-depth profiles from boreholes in the Atacama Desert in central and northern Chile. After screening these profiles, we found that only nine profiles at four different sites were suitable to invert for ground temperature history. For all the sites, no surface temperature variations could be resolved for the period 1500-1800. In the northern coastal region of Chile, there is no perceptible temperature variation at all from 1500 to present. In the northern central Chile region, between 26 and 28° S, the data suggest a cooling from ≈ 1850 to ≈ 1980 followed by a 1.9 K warming starting ≈ 20-40 years BP. This result is consistent with the ground surface temperature histories for Peru and the semiarid regions of South America. The duration of the cooling trend is poorly resolved and it may coincide with a marked short cooling interval in the 1960s that is found in meteorological records. The total warming is greater than that inferred from proxy climate reconstructions for central Chile and southern South America, and by the PMIP3-CMIP5 surface temperature simulations for the north-central Chile grid points. The differences among different climate reconstructions, meteorological records, and models are likely due to differences in spatial and temporal resolution among the various data sets and the models.

  19. Twilight and nighttime ionospheric temperatures from oxygen wavelengths 6300 and 5577 spectral line profiles

    NASA Technical Reports Server (NTRS)

    Feibelman, W. A.; Hake, R. D., Jr.; Sipler, D. P.; Biondi, M. A.

    1971-01-01

    Fabry-Perot interferometer measurements of atomic oxygen 6300 A and 5577 A line profiles from twilight and nightglow are used to determine the neutral temperatures in F2 and E regions of the earth's ionosphere. The exospheric temperatures T sub n (infinity) determined from the 6300 A profiles are usually somewhat higher than those calculated from Jacchia's model, with differences as large as approximately 300 K noted when T sub n (infinity) = 1500 to 1600 K. The post-sunset and pre-dawn rate of change of T sub n (infinity) is often substantially larger than the Jacchia prediction. The 5577 A (E-region) measured temperatures range from 200 to 220 K on quiet nights to 500 to 600 K during geomagnetic storms.

  20. Heat Exchange with Air and Temperature Profile of a Moving Oversize Tire

    NASA Astrophysics Data System (ADS)

    Grinchuk, P. S.; Fisenko, S. P.

    2016-11-01

    A one-dimensional mathematical model of heat transfer in a tire with account for the deformation energy dissipation and heat exchange of a moving tire with air has been developed. The mean temperature profiles are calculated and transition to a stationary thermal regime is considered. The influence of the rate of energy dissipation and of effective thermal conductivity of rubber on the temperature field is investigated quantitatively.

  1. Cooperative Lamb shift and superradiance in an optoelectronic device

    NASA Astrophysics Data System (ADS)

    Frucci, G.; Huppert, S.; Vasanelli, A.; Dailly, B.; Todorov, Y.; Beaudoin, G.; Sagnes, I.; Sirtori, C.

    2017-04-01

    When a single excitation is shared between a large number of two-level systems, a strong enhancement of the spontaneous emission appears. This phenomenon is known as superradiance. This enhanced rate can be accompanied by a shift of the emission frequency, the cooperative Lamb shift, issued from the exchange of virtual photons between the emitters. In this work we present a semiconductor optoelectronic device allowing the observation of these two phenomena at room temperature. We demonstrate experimentally and theoretically that plasma oscillations in spatially separated quantum wells interact through real and virtual photon exchange. This gives rise to a superradiant mode displaying a large cooperative Lamb shift.

  2. Virtual Instrument for Determining Rate Constant of Second-Order Reaction by pX Based on LabVIEW 8.0.

    PubMed

    Meng, Hu; Li, Jiang-Yuan; Tang, Yong-Huai

    2009-01-01

    The virtual instrument system based on LabVIEW 8.0 for ion analyzer which can measure and analyze ion concentrations in solution is developed and comprises homemade conditioning circuit, data acquiring board, and computer. It can calibrate slope, temperature, and positioning automatically. When applied to determine the reaction rate constant by pX, it achieved live acquiring, real-time displaying, automatical processing of testing data, generating the report of results; and other functions. This method simplifies the experimental operation greatly, avoids complicated procedures of manual processing data and personal error, and improves veracity and repeatability of the experiment results.

  3. Vibrons in finite size molecular lattices: a route for high-fidelity quantum state transfer at room temperature.

    PubMed

    Pouthier, Vincent

    2012-11-07

    A communication protocol is proposed in which vibron-mediated quantum state transfer takes place in a molecular lattice. We consider two distant molecular groups grafted on each side of the lattice. These groups form two quantum computers where vibrational qubits are implemented and received. The lattice defines the communication channel along which a vibron delocalizes and interacts with a phonon bath. Using quasi-degenerate perturbation theory, vibron-phonon entanglement is taken into account through the effective Hamiltonian concept. A vibron is thus dressed by a virtual phonon cloud whereas a phonon is clothed by virtual vibronic transitions. It is shown that three quasi-degenerate dressed states define the relevant paths followed by a vibron to tunnel between the computers. When the coupling between the computers and the lattice is judiciously chosen, constructive interference takes place between these paths. Phonon-induced decoherence is minimized and a high-fidelity quantum state transfer occurs over a broad temperature range.

  4. Evaluation of the separation performance of polyvinylpyrrolidone as a virtual stationary phase for chromatographic NMR.

    PubMed

    Huang, Shaohua; Wu, Rui; Bai, Zhengwu; Yang, Ying; Li, Suying; Dou, Xiaowei

    2014-09-01

    Polyvinylpyrrolidone (PVP) was used as a virtual stationary phase to separate p-xylene, benzyl alcohol, and p-methylphenol by the chromatographic NMR technique. The effects of concentration and weight-average molecular weight (Mw) of PVP, solvent viscosity, solvent polarity, and sample temperature on the resolution of these components were investigated. It was found that both higher PVP concentration and higher PVP Mw caused the increase of diffusion resolution for the three components. Moreover, the diffusion resolution did not change at viscosity-higher solvents. Moreover, the three components showed different resolution at different solvents. As temperature increased, the diffusion resolution between p-xylene and benzyl alcohol gradually increased, and the one between p-xylene and p-methylphenol slightly increased from 278 to 298 K and then decreased above 298 K. It was also found that the polarity of the analytes played an important role for the separation by affecting the diffusion coefficient. Copyright © 2014 John Wiley & Sons, Ltd.

  5. RF current profile control studies in the alcator C-mod tokamak

    NASA Astrophysics Data System (ADS)

    Bonoli, P. T.; Porkolab, M.; Wukitch, S. J.; Bernabei, S.; Kaita, R.; Mikkelsen, D.; Phillips, C. K.; Schilling, G.

    1999-09-01

    Time dependent calculations of lower hybrid (LH) current profile control in Alcator C-Mod have been done using the TRANSP [1], FPPRF [2], and LSC [3] codes. Up to 3 MW of LH current drive power was applied in plasmas with high power ICRF minority heating (PICH=1.8-3 MW) and fast current ramp up. Using the experimentally measured temperature profiles, off-axis current generation resulted in nonmonotonic q-profiles with qmin~=1.6. Self-consistent effects of off-axis electron heating by the LH power were also included in the analysis and significant broadening of the electron temperature profile was found with qmin>~2 and a larger shear reversal radius.

  6. One-dimensional scanning of moisture in heated porous building materials with NMR.

    PubMed

    van der Heijden, G H A; Huinink, H P; Pel, L; Kopinga, K

    2011-02-01

    In this paper we present a new dedicated NMR setup which is capable of measuring one-dimensional moisture profiles in heated porous materials. The setup, which is placed in the bore of a 1.5 T whole-body scanner, is capable of reaching temperatures up to 500 °C. Moisture and temperature profiles can be measured quasi simultaneously with a typical time resolution of 2-5 min. A methodology is introduced for correcting temperature effects on NMR measurements at these elevated temperatures. The corrections are based on the Curie law for paramagnetism and the observed temperature dependence of the relaxation mechanisms occurring in porous materials. Both these corrections are used to obtain a moisture content profile from the raw NMR signal profile. To illustrate the methodology, a one-sided heating experiment of concrete with a moisture content in equilibrium with 97% RH is presented. This kind of heating experiment is of particular interest in the research on fire spalling of concrete, since it directly reveals the moisture and heat transport occurring inside the concrete. The obtained moisture profiles reveal a moisture peak building up behind the boiling front, resulting in a saturated layer. To our knowledge the direct proof of the formation of a moisture peak and subsequent moisture clogging has not been reported before. Copyright © 2010 Elsevier Inc. All rights reserved.

  7. Modelling the influence of elevation and snow regime on winter stream temperature in the rain-on-snow zone

    NASA Astrophysics Data System (ADS)

    Leach, J.; Moore, D.

    2015-12-01

    Winter stream temperature of coastal mountain catchments influences fish growth and development. Transient snow cover and advection associated with lateral throughflow inputs are dominant controls on stream thermal regimes in these regions. Existing stream temperature models lack the ability to properly simulate these processes. Therefore, we developed and evaluated a conceptual-parametric catchment-scale stream temperature model that includes the role of transient snow cover and lateral advection associated with throughflow. The model provided reasonable estimates of observed stream temperature at three test catchments. We used the model to simulate winter stream temperature for virtual catchments located at different elevations within the rain-on-snow zone. The modelling exercise examined stream temperature response associated with interactions between elevation, snow regime, and changes in air temperature. Modelling results highlight that the sensitivity of winter stream temperature response to changes in climate may be dependent on catchment elevation and landscape position.

  8. Low-threshold high-T/0/ constricted double heterojunction AlGaAs diode lasers

    NASA Technical Reports Server (NTRS)

    Botez, D.; Connolly, J. C.

    1980-01-01

    Constricted double heterojunction diode lasers of relatively low CW thresholds (28-40 mA) are obtained by growing structures that maximize the amount of current flow into the lasing spot. These values are obtained while still using standard 10 microns wide oxide-defined stripe contacts. Over the 20-70 C temperature interval, threshold current temperature coefficients as high as 320 C and a virtually constant external differential quantum efficiency, are found.

  9. Room Temperature Electroluminescence from Tensile-Strained Si0.13Ge0.87/Ge Multiple Quantum Wells on a Ge Virtual Substrate

    PubMed Central

    Lin, Guangyang; Chen, Ningli; Zhang, Lu; Huang, Zhiwei; Huang, Wei; Wang, Jianyuan; Xu, Jianfang; Chen, Songyan; Li, Cheng

    2016-01-01

    Direct band electroluminescence (EL) from tensile-strained Si0.13Ge0.87/Ge multiple quantum wells (MQWs) on a Ge virtual substrate (VS) at room temperature is reported herein. Due to the competitive result of quantum confinement Stark effect and bandgap narrowing induced by tensile strain in Ge wells, electroluminescence from Γ1-HH1 transition in 12-nm Ge wells was observed at around 1550 nm. As injection current density increases, additional emission shoulders from Γ2-HH2 transition in Ge wells and Ge VS appeared at around 1300–1400 nm and 1600–1700 nm, respectively. The peak energy of EL shifted to the lower energy side superquadratically with an increase of injection current density as a result of the Joule heating effect. During the elevation of environmental temperature, EL intensity increased due to a reduction of energy between L and Γ valleys of Ge. Empirical fitting of the relationship between the integrated intensity of EL (L) and injection current density (J) with L~Jm shows that the m factor increased with injection current density, suggesting higher light emitting efficiency of the diode at larger injection current densities, which can be attributed to larger carrier occupations in the Γ valley and the heavy hole (HH) valance band at higher temperatures. PMID:28773923

  10. Room Temperature Electroluminescence from Tensile-Strained Si0.13Ge0.87/Ge Multiple Quantum Wells on a Ge Virtual Substrate.

    PubMed

    Lin, Guangyang; Chen, Ningli; Zhang, Lu; Huang, Zhiwei; Huang, Wei; Wang, Jianyuan; Xu, Jianfang; Chen, Songyan; Li, Cheng

    2016-09-27

    Direct band electroluminescence (EL) from tensile-strained Si 0.13 Ge 0.87 /Ge multiple quantum wells (MQWs) on a Ge virtual substrate (VS) at room temperature is reported herein. Due to the competitive result of quantum confinement Stark effect and bandgap narrowing induced by tensile strain in Ge wells, electroluminescence from Γ1-HH1 transition in 12-nm Ge wells was observed at around 1550 nm. As injection current density increases, additional emission shoulders from Γ2-HH2 transition in Ge wells and Ge VS appeared at around 1300-1400 nm and 1600-1700 nm, respectively. The peak energy of EL shifted to the lower energy side superquadratically with an increase of injection current density as a result of the Joule heating effect. During the elevation of environmental temperature, EL intensity increased due to a reduction of energy between L and Γ valleys of Ge. Empirical fitting of the relationship between the integrated intensity of EL ( L ) and injection current density ( J ) with L ~ J m shows that the m factor increased with injection current density, suggesting higher light emitting efficiency of the diode at larger injection current densities, which can be attributed to larger carrier occupations in the Γ valley and the heavy hole (HH) valance band at higher temperatures.

  11. RECOZ data reduction and analysis: Programs and procedures

    NASA Technical Reports Server (NTRS)

    Reed, E. I.

    1984-01-01

    The RECOZ data reduction programs transform data from the RECOZ photometer to ozone number density and overburden as a function of altitude. Required auxiliary data are the altitude profile versus time and for appropriate corrections to the ozone cross sections and scattering effects, air pressure and temperature profiles. Air temperature and density profiles may also be used to transform the ozone density versus geometric altitude to other units, such as to ozone partial pressure or mixing ratio versus pressure altitude. There are seven programs used to accomplish this: RADAR, LISTRAD, RAW OZONE, EDIT OZONE, MERGE, SMOOTH, and PROFILE.

  12. The Baryonic and Dark Matter Distributions in Abell 401

    NASA Astrophysics Data System (ADS)

    Nevalainen, J.; Markevitch, M.; Forman, W.

    1999-11-01

    We combine spatially resolved ASCA temperature data with ROSAT imaging data to constrain the total mass distribution in the cluster A401, assuming that the cluster is in hydrostatic equilibrium, but without the assumption of gas isothermality. We obtain a total mass within the X-ray core (290 h-150 kpc) of 1.2+0.1-0.5×1014 h-150 Msolar at the 90% confidence level, 1.3 times larger than the isothermal estimate. The total mass within r500 (1.7 h-150 Mpc) is M500=0.9+0.3-0.2×1015 h-150 Msolar at 90% confidence, in agreement with the optical virial mass estimate, and 1.2 times smaller than the isothermal estimate. Our M500 value is 1.7 times smaller than that estimated using the mass-temperature scaling law predicted by simulations. The best-fit dark matter density profile scales as r-3.1 at large radii, which is consistent with the Navarro, Frenk & White (NFW) ``universal profile'' as well as the King profile of the galaxy density in A401. From the imaging data, the gas density profile is shallower than the dark matter profile, scaling as r-2.1 at large radii, leading to a monotonically increasing gas mass fraction with radius. Within r500 the gas mass fraction reaches a value of fgas=0.21+0.06-0.05 h-3/250 (90% confidence errors). Assuming that fgas (plus an estimate of the stellar mass) is the universal value of the baryon fraction, we estimate the 90% confidence upper limit of the cosmological matter density to be Ωm<0.31, in conflict with an Einstein-deSitter universe. Even though the NFW dark matter density profile is statistically consistent with the temperature data, its central temperature cusp would lead to convective instability at the center, because the gas density does not have a corresponding peak. One way to reconcile a cusp-shaped total mass profile with the observed gas density profile, regardless of the temperature data, is to introduce a significant nonthermal pressure in the center. Such a pressure must satisfy the hydrostatic equilibrium condition without inducing turbulence. Alternately, significant mass drop-out from the cooling flow would make the temperature less peaked and the NFW profile acceptable. However, the quality of data is not adequate to test this possibility.

  13. The thermal structure of Titan’s upper atmosphere, I: Temperature profiles from Cassini INMS observations

    NASA Astrophysics Data System (ADS)

    Snowden, D.; Yelle, R. V.; Cui, J.; Wahlund, J.-E.; Edberg, N. J. T.; Ågren, K.

    2013-09-01

    We derive vertical temperature profiles from Ion Neutral Mass Spectrometer (INMS) N2 density measurements from 32 Cassini passes. We find that the average temperature of Titan’s thermosphere varies significantly from pass-to-pass between 112 and 175 K. The temperatures from individual temperature profiles also varies considerably, with many passes exhibiting wave-like temperature perturbations and large temperature gradients. Wave-like temperature perturbations have wavelengths between 150 and 420 km and amplitudes between 3% and 22% and vertical wave power spectra of the INMS data and HASI data have a slope between -2 and -3, which is consistent with vertically propagating atmospheric waves. The lack of a strong correlation between temperature and latitude, longitude, solar zenith angle, or local solar time indicates that the thermal structure of Titan’s thermosphere is not primarily determined by the absorption of solar EUV flux. At N2 densities greater than 108 cm-3, Titan’s thermosphere is colder when Titan is observed in Saturn’s magnetospheric lobes compared to Saturn’s plasma sheet as proposed by Westlake et al. (Westlake, J.H. et al. [2011]. J. Geophys. Res. 116, A03318. http://dx.doi.org/10.1029/2010JA016251). This apparent correlation suggests that magnetospheric particle precipitation causes the temperature variability in Titan’s thermosphere; however, at densities smaller than 108 cm-3 the lobe passes are hotter than the plasma sheet passes and we find no correlation between the temperature of Titan’s thermosphere and ionospheric signatures of enhanced particle precipitation, which suggests that the correlation is not indicative of a physical connection. The temperature of Titan’s thermosphere also may have decreased by ∼10 K around mid-2007. Finally, we classify the vertical temperature profiles to show which passes are hot and cold and which passes have the largest temperature variations. In a companion paper (Part II), we estimate the strength of energy sources and sinks in Titan’s thermosphere.

  14. Pulsed photothermal depth profiling of tattoos undergoing laser removal treatment

    NASA Astrophysics Data System (ADS)

    Milanic, Matija; Majaron, Boris

    2012-02-01

    Pulsed photothermal radiometry (PPTR) allows noninvasive determination of temperature depth profiles induced by pulsed laser irradiation of strongly scattering biological tissues and organs, including human skin. In present study, we evaluate the potential of this technique for investigational characterization and possibly quantitative evaluation of laser tattoo removal. The study involved 5 healthy volunteers (3 males, 2 females), age 20-30 years, undergoing tattoo removal treatment using a Q-switched Nd:YAG laser. There were four measurement and treatment sessions in total, separated by 2-3 months. Prior to each treatment, PPTR measurements were performed on several tattoo sites and one nearby healthy site in each patient, using a 5 ms Nd:YAG laser at low radiant exposure values and a dedicated radiometric setup. The laser-induced temperature profiles were then reconstructed by applying a custom numerical code. In addition, each tatoo site was documented with a digital camera and measured with a custom colorimetric system (in tristimulus color space), providing an objective evaluation of the therapeutic efficacy to be correlated with our PPTR results. The results show that the laser-induced temperature profile in untreated tattoos is invariably located at a subsurface depth of 300 μm. In tattoo sites that responded well to laser therapy, a significant drop of the temperature peak was observed in the profiles obtained from PPTR record. In several sites that appeared less responsive, as evidenced by colorimetric data, a progressive shift of the temperature profile deeper into the dermis was observed over the course of consecutive laser treatments, indicating that the laser tattoo removal was efficient.

  15. Molecular Mechanisms Regulating Temperature Compensation of the Circadian Clock.

    PubMed

    Narasimamurthy, Rajesh; Virshup, David M

    2017-01-01

    An approximately 24-h biological timekeeping mechanism called the circadian clock is present in virtually all light-sensitive organisms from cyanobacteria to humans. The clock system regulates our sleep-wake cycle, feeding-fasting, hormonal secretion, body temperature, and many other physiological functions. Signals from the master circadian oscillator entrain peripheral clocks using a variety of neural and hormonal signals. Even centrally controlled internal temperature fluctuations can entrain the peripheral circadian clocks. But, unlike other chemical reactions, the output of the clock system remains nearly constant with fluctuations in ambient temperature, a phenomenon known as temperature compensation. In this brief review, we focus on recent advances in our understanding of the posttranslational modifications, especially a phosphoswitch mechanism controlling the stability of PER2 and its implications for the regulation of temperature compensation.

  16. Integrated modeling of temperature and rotation profiles in JET ITER-like wall discharges

    NASA Astrophysics Data System (ADS)

    Rafiq, T.; Kritz, A. H.; Kim, Hyun-Tae; Schuster, E.; Weiland, J.

    2017-10-01

    Simulations of 78 JET ITER-like wall D-D discharges and 2 D-T reference discharges are carried out using the TRANSP predictive integrated modeling code. The time evolved temperature and rotation profiles are computed utilizing the Multi-Mode anomalous transport model. The discharges involve a broad range of conditions including scans over gyroradius, collisionality, and values of q95. The D-T reference discharges are selected in anticipation of the D-T experimental campaign planned at JET in 2019. The simulated temperature and rotation profiles are compared with the corresponding experimental profiles in the radial range from the magnetic axis to the ρ = 0.9 flux surface. The comparison is quantified by calculating the RMS deviations and Offsets. Overall, good agreement is found between the profiles produced in the simulations and the experimental data. It is planned that the simulations obtained using the Multi-Mode model will be compared with the simulations using the TGLF model. Research supported in part by the US, DoE, Office of Sciences.

  17. In Vivo Simulator for Microwave Treatment

    NASA Technical Reports Server (NTRS)

    Arndt, G. Dickey (Inventor); Carl, James R. (Inventor); Raffoul, George W. (Inventor); Karasack, Vincent G. (Inventor); Pacifico, Antonio (Inventor); Pieper, Carl F. (Inventor)

    2001-01-01

    Method and apparatus are provided for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue to treat ventricular tachycardia and other arrhythmias while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna is effective for this purpose over a bandwidth of about 6 GHz. A computer simulation provides initial screening capabilities for an antenna such as antenna. frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In operation, microwave energy between about 1 GHz and 12 GHz is applied to monopole microwave radiator having a surface wave limiter. A test setup provides physical testing of microwave radiators to determine the temperature profile created in actual heart tissue or ersatz heart tissue. Saline solution pumped over the heart tissue with a peristaltic pump simulates blood flow. Optical temperature sensors disposed at various tissue depths within the heart tissue detect the temperature profile without creating any electromagnetic interference. The method may be used to produce a desired temperature profile in other body tissues reachable by catheter such as tumors and the like.

  18. Transcatheter Antenna For Microwave Treatment

    NASA Technical Reports Server (NTRS)

    Arndt, G. Dickey (Inventor); Carl, James R. (Inventor); Raffoul, George W. (Inventor); Karasack, Vincent G. (Inventor); Pacifico, Antonio (Inventor); Pieper, Carl F. (Inventor)

    2000-01-01

    Method and apparatus are provided for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue to treat ventricular tachycardia and other arrhythmias while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In operation, microwave energy between about 1 Gigahertz and 12 Gigahertz is applied to monopole microwave radiation having a surface wave limiter. A test setup provides physical testing of microwave radiators to determine the temperature profile created in actual heart tissue or ersatz heart tissue. Saline solution pumped over the heart tissue with a peristaltic pump simulates blood flow. Optical temperature sensors disposed at various tissue depths within the heart tissue detect the temperature profile without creating any electromagnetic interference. The method may he used to produce a desired temperature profile in other body tissues reachable by catheter such as tumors and the like.

  19. Microwave Treatment for Cardiac Arrhythmias

    NASA Technical Reports Server (NTRS)

    Arndt, G. Dickey (Inventor); Carl, James R. (Inventor); Raffoul, George W. (Inventor); Pacifico, Antonio (Inventor)

    1999-01-01

    Method and apparatus are provided for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue to treat ventricular tachycardia and other arrhythmias while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In operation, microwave energy between about 1 Gigahertz and 12 Gigahertz is applied to monopole microwave radiator having a surface wave limiter. A test setup provides physical testing of microwave radiators to determine the temperature profile created in actual heart tissue or ersatz heart tissue. Saline solution pumped over the heart tissue with a peristaltic pump simulates blood flow. Optical temperature sensors disposed at various tissue depths within the heart tissue detect the temperature profile without creating any electromagnetic interference. The method may be used to produce a desired temperature profile in other body tissues reachable by catheter such as tumors and the like.

  20. Modeling and life prediction methodology for Titanium Matrix Composites subjected to mission profiles

    NASA Technical Reports Server (NTRS)

    Mirdamadi, M.; Johnson, W. S.

    1994-01-01

    Titanium matrix composites (TMC) are being evaluated as structural materials for elevated temperature applications in future generation hypersonic vehicles. In such applications, TMC components are subjected to complex thermomechanical loading profiles at various elevated temperatures. Therefore, thermomechanical fatigue (TMF) testing, using a simulated mission profile, is essential for evaluation and development of life prediction methodologies. The objective of the research presented in this paper was to evaluate the TMF response of the (0/90)2s SCS-6/Timetal-21S subjected to a generic hypersonic flight profile and its portions with a temperature ranging from -130 C to 816 C. It was found that the composite modulus, prior to rapid degradation, had consistent values for all the profiles tested. A micromechanics based analysis was used to predict the stress-strain response of the laminate and of the constituents in each ply during thermomechanical loading conditions by using only constituent properties as input. The fiber was modeled as elastic with transverse orthotropic and temperature dependent properties. The matrix was modeled using a thermoviscoplastic constitutive relation. In the analysis, the composite modulus degradation was assumed to result from matrix cracking and was modeled by reducing the matrix modulus. Fatigue lives of the composite subjected to the complex generic hypersonic flight profile were well correlated using the predicted stress in 0 degree fibers.

  1. Preliminary analysis of hot spot factors in an advanced reactor for space electric power systems

    NASA Technical Reports Server (NTRS)

    Lustig, P. H.; Holms, A. G.; Davison, H. W.

    1973-01-01

    The maximum fuel pin temperature for nominal operation in an advanced power reactor is 1370 K. Because of possible nitrogen embrittlement of the clad, the fuel temperature was limited to 1622 K. Assuming simultaneous occurrence of the most adverse conditions a deterministic analysis gave a maximum fuel temperature of 1610 K. A statistical analysis, using a synthesized estimate of the standard deviation for the highest fuel pin temperature, showed probabilities of 0.015 of that pin exceeding the temperature limit by the distribution free Chebyshev inequality and virtually nil assuming a normal distribution. The latter assumption gives a 1463 K maximum temperature at 3 standard deviations, the usually assumed cutoff. Further, the distribution and standard deviation of the fuel-clad gap are the most significant contributions to the uncertainty in the fuel temperature.

  2. Study of ion-ion plasma formation in negative ion sources by a three-dimensional in real space and three-dimensional in velocity space particle in cell model

    NASA Astrophysics Data System (ADS)

    Nishioka, S.; Goto, I.; Miyamoto, K.; Hatayama, A.; Fukano, A.

    2016-01-01

    Recently, in large-scale hydrogen negative ion sources, the experimental results have shown that ion-ion plasma is formed in the vicinity of the extraction hole under the surface negative ion production case. The purpose of this paper is to clarify the mechanism of the ion-ion plasma formation by our three dimensional particle-in-cell simulation. In the present model, the electron loss along the magnetic filter field is taken into account by the " √{τ///τ⊥ } model." The simulation results show that the ion-ion plasma formation is due to the electron loss along the magnetic filter field. Moreover, the potential profile for the ion-ion plasma case has been looked into carefully in order to discuss the ion-ion plasma formation. Our present results show that the potential drop of the virtual cathode in front of the plasma grid is large when the ion-ion plasma is formed. This tendency has been explained by a relationship between the virtual cathode depth and the net particle flux density at the virtual cathode.

  3. Utilizing neuronavigation for virtual electrode representation and safe resection following SEEG; a technical report.

    PubMed

    Brandmeir, Nicholas; Sather, Michael

    2018-02-20

    One of the most effective treatments for epilepsy is resection, but it remains underutilized. Efforts must be made to increase the ease, safety, and efficacy of epilepsy resection to improve utilization. Studies have shown an improved risk profile of stereoelectroencephalography (SEEG) over subdural grids (SDG) for invasive monitoring. One limitation to increased adoption of SEEG at epilepsy centers is the theoretical difficulty of planning a delayed resection once electrodes are removed. Our objective was to develop and present a technique using readily available neuronavigation technology to guide a cortical, non-lesional epilepsy resection with co-registration of imaging during invasive monitoring to imaging in an explanted patient, allowing for virtual visualization of electrodes. An example case taking advantage of the technique described above as an adjunct for an anatomically guided resection is presented with technical details and images. Intraoperative neuronavigation was successfully used to virtually represent previously removed SEEG electrodes and accuracy could be easily verified by examining scars on the scalp, bone, dura and pia. The simple technique presented can be a useful adjunct to resection following SEEG. This may help increase the adoption of SEEG, even when resection is planned.

  4. An optical fiber expendable seawater temperature/depth profile sensor

    NASA Astrophysics Data System (ADS)

    Zhao, Qiang; Chen, Shizhe; Zhang, Keke; Yan, Xingkui; Yang, Xianglong; Bai, Xuejiao; Liu, Shixuan

    2017-10-01

    Marine expendable temperature/depth profiler (XBT) is a disposable measuring instrument which can obtain temperature/depth profile data quickly in large area waters and mainly used for marine surveys, scientific research, military application. The temperature measuring device is a thermistor in the conventional XBT probe (CXBT)and the depth data is only a calculated value by speed and time depth calculation formula which is not an accurate measurement result. Firstly, an optical fiber expendable temperature/depth sensor based on the FBG-LPG cascaded structure is proposed to solve the problems of the CXBT, namely the use of LPG and FBG were used to detect the water temperature and depth, respectively. Secondly, the fiber end reflective mirror is used to simplify optical cascade structure and optimize the system performance. Finally, the optical path is designed and optimized using the reflective optical fiber end mirror. The experimental results show that the sensitivity of temperature and depth sensing based on FBG-LPG cascade structure is about 0.0030C and 0.1%F.S. respectively, which can meet the requirements of the sea water temperature/depth observation. The reflectivity of reflection mirror is in the range from 48.8% to 72.5%, the resonant peak of FBG and LPG are reasonable and the whole spectrum are suitable for demodulation. Through research on the optical fiber XBT (FXBT), the direct measurement of deep-sea temperature/depth profile data can be obtained simultaneously, quickly and accurately. The FXBT is a new all-optical seawater temperature/depth sensor, which has important academic value and broad application prospect and is expected to replace the CXBT in the future.

  5. Combustion studies of coal derived solid fuels by thermogravimetric analysis. III. Correlation between burnout temperature and carbon combustion efficiency

    USGS Publications Warehouse

    Rostam-Abadi, M.; DeBarr, J.A.; Chen, W.T.

    1990-01-01

    Burning profiles of 35-53 ??m size fractions of an Illinois coal and three partially devolatilized coals prepared from the original coal were obtained using a thermogravimetric analyzer. The burning profile burnout temperatures were higher for lower volatile fuels and correlated well with carbon combustion efficiencies of the fuels when burned in a laboratory-scale laminar flow reactor. Fuels with higher burnout temperatures had lower carbon combustion efficiencies under various time-temperature conditions in the laboratory-scale reactor. ?? 1990.

  6. Azimuthally averaged radial S(sub 100 microns)/S(sub 60 microns) dust color temperatures in spiral galaxies

    NASA Technical Reports Server (NTRS)

    Devereux, Nick A.

    1994-01-01

    The IRAS S(sub 100 micron)/S(sub 60 micron) dust color temperature profiles are presented for two nearby spiral galaxies M 101 and M 81. The radial dust temperature profiles provided an important constraint on the origin of the far-infrared luminosity. The observed dust temperature is compared with that expected for diffuse interstellar dust heated by the general interstellar radiation field within each galaxy. The implications for the contribution of cirrus to the far-infrared luminosity of M 101 and M 81 are discussed.

  7. Water-level sensor and temperature-profile detector

    DOEpatents

    Not Available

    1981-01-29

    A temperature profile detector is described which comprises a surrounding length of metal tubing and an interior electrical conductor both constructed of high temperature high electrical resistance materials. A plurality of gas-filled expandable bellows made of electrically conductive material are positioned at spaced locations along a length of the conductors. The bellows are sealed and contain a predetermined volume of a gas designed to effect movement of the bellows from an open circuit condition to a closed circuit condition in response to monitored temperature changes sensed by each bellows.

  8. Water level sensor and temperature profile detector

    DOEpatents

    Tokarz, Richard D.

    1983-01-01

    A temperature profile detector comprising a surrounding length of metal tubing and an interior electrical conductor both constructed of high temperature high electrical resistance materials. A plurality of gas-filled expandable bellows made of electrically conductive material is electrically connected to the interior electrical conductor and positioned within the length of metal tubing. The bellows are sealed and contain a predetermined volume of a gas designed to effect movement of the bellows from an open circuit condition to a closed circuit condition in response to monitored temperature changes sensed by each bellows.

  9. NIMBUS-5 sounder data processing system. Part 2: Results

    NASA Technical Reports Server (NTRS)

    Smith, W. L.; Woolf, H. M.; Hayden, C. M.; Shen, W. C.

    1975-01-01

    The Nimbus-5 spacecraft carries infrared and microwave radiometers for sensing the temperature distribution of the atmosphere. Methods developed for obtaining temperature profiles from the combined set of infrared and microwave radiation measurements are described. Algorithms used to determine (a) vertical temperature and water vapor profiles, (b) cloud height, fractional coverage, and liquid water content, (c) surface temperature, and (d) total outgoing longwave radiation flux are described. Various meteorological results obtained from the application of the Nimbus-5 sounding data processing system during 1973 and 1974 are presented.

  10. The power of vertical geolocation of atmospheric profiles from GNSS radio occultation.

    PubMed

    Scherllin-Pirscher, Barbara; Steiner, Andrea K; Kirchengast, Gottfried; Schwärz, Marc; Leroy, Stephen S

    2017-02-16

    High-resolution measurements from Global Navigation Satellite System (GNSS) radio occultation (RO) provide atmospheric profiles with independent information on altitude and pressure. This unique property is of crucial advantage when analyzing atmospheric characteristics that require joint knowledge of altitude and pressure or other thermodynamic atmospheric variables. Here we introduce and demonstrate the utility of this independent information from RO and discuss the computation, uncertainty, and use of RO atmospheric profiles on isohypsic coordinates-mean sea level altitude and geopotential height-as well as on thermodynamic coordinates (pressure and potential temperature). Using geopotential height as vertical grid, we give information on errors of RO-derived temperature, pressure, and potential temperature profiles and provide an empirical error model which accounts for seasonal and latitudinal variations. The observational uncertainty of individual temperature/pressure/potential temperature profiles is about 0.7 K/0.15%/1.4 K in the tropopause region. It gradually increases into the stratosphere and decreases toward the lower troposphere. This decrease is due to the increasing influence of background information. The total climatological error of mean atmospheric fields is, in general, dominated by the systematic error component. We use sampling error-corrected climatological fields to demonstrate the power of having different and accurate vertical coordinates available. As examples we analyze characteristics of the location of the tropopause for geopotential height, pressure, and potential temperature coordinates as well as seasonal variations of the midlatitude jet stream core. This highlights the broad applicability of RO and the utility of its versatile vertical geolocation for investigating the vertical structure of the troposphere and stratosphere.

  11. Analysis of temperature profiles for investigating stream losses beneath ephemeral channels

    USGS Publications Warehouse

    Constantz, Jim; Stewart, Amy E.; Niswonger, Richard G.; Sarma, Lisa

    2002-01-01

    Continuous estimates of streamflow are challenging in ephemeral channels. The extremely transient nature of ephemeral streamflows results in shifting channel geometry and degradation in the calibration of streamflow stations. Earlier work suggests that analysis of streambed temperature profiles is a promising technique for estimating streamflow patterns in ephemeral channels. The present work provides a detailed examination of the basis for using heat as a tracer of stream/groundwater exchanges, followed by a description of an appropriate heat and water transport simulation code for ephemeral channels, as well as discussion of several types of temperature analysis techniques to determine streambed percolation rates. Temperature‐based percolation rates for three ephemeral stream sites are compared with available surface water estimates of channel loss for these sites. These results are combined with published results to develop conclusions regarding the accuracy of using vertical temperature profiles in estimating channel losses. Comparisons of temperature‐based streambed percolation rates with surface water‐based channel losses indicate that percolation rates represented 30% to 50% of the total channel loss. The difference is reasonable since channel losses include both vertical and nonvertical component of channel loss as well as potential evapotranspiration losses. The most significant advantage of the use of sediment‐temperature profiles is their robust and continuous nature, leading to a long‐term record of the timing and duration of channel losses and continuous estimates of streambed percolation. The primary disadvantage is that temperature profiles represent the continuous percolation rate at a single point in an ephemeral channel rather than an average seepage loss from the entire channel.

  12. Upper-Ocean Variability in the Arctic’s Amundsen and Nansen Basins

    DTIC Science & Technology

    2017-05-01

    collect vertical profiles of ocean temperature, salinity and horizontal velocity at few- hour interval as well as sample for specified time periods...deployed for the MIZ program - specifically, vertical temperature, salinity and velocity profiles were collected every 3 hours in the upper 250m of the...the system), this ITP-V returned 5+ months of upper ocean temperature, salinity , velocity and turbulence data from the Makarov Basin, a region of

  13. Measuring temperature and field profiles in heat assisted magnetic recording

    NASA Astrophysics Data System (ADS)

    Hohlfeld, J.; Zheng, X.; Benakli, M.

    2015-08-01

    We introduce a theoretical and experimental framework that enables quantitative measurements of the temperature and magnetic field profiles governing the thermo-magnetic write process in heat assisted magnetic recording. Since our approach allows the identification of the correct temperature dependence of the magneto-crystalline anisotropy field in the vicinity of the Curie point as well, it provides an unprecedented experimental foundation to assess our understanding of heat assisted magnetic recording.

  14. Assimilation of NUCAPS Retrieved Profiles in GSI for Unique Forecasting Applications

    NASA Technical Reports Server (NTRS)

    Berndt, Emily Beth; Zavodsky, Bradley; Srikishen, Jayanthi; Blankenship, Clay

    2015-01-01

    Hyperspectral IR profiles can be assimilated in GSI as a separate observation other than radiosondes with only changes to tables in the fix directory. Assimilation of profiles does produce changes to analysis fields and evidenced by: Innovations larger than +/-2.0 K are present and represent where individual profiles impact the final temperature analysis.The updated temperature analysis is colder behind the cold front and warmer in the warm sector. The updated moisture analysis is modified more in the low levels and tends to be drier than the original model background Analysis of model output shows: Differences relative to 13-km RAP analyses are smaller when profiles are assimilated with NUCAPS errors. CAPE is under-forecasted when assimilating NUCAPS profiles, which could be problematic for severe weather forecasting Refining the assimilation technique to incorporate an error covariance matrix and creating a separate GSI module to assimilate satellite profiles may improve results.

  15. System and method for glass processing and temperature sensing

    DOEpatents

    Shepard, Chester L.; Cannon, Bret D.; Khaleel, Mohammad A.

    2004-09-28

    Techniques for measuring the temperature at various locations through the thickness of glass products and to control the glass processing operation with the sensed temperature information are disclosed. Fluorescence emission of iron or cerium in glass is excited and imaged onto segmented detectors. Spatially resolved temperature data are obtained through correlation of the detected photoluminescence signal with location within the glass. In one form the detected photoluminescence is compared to detected scattered excitation light to determine temperature. Stress information is obtained from the time history of the temperature profile data and used to evaluate the quality of processed glass. A heating or cooling rate of the glass is also controlled to maintain a predetermined desired temperature profile in the glass.

  16. Bacterial symbionts, Buchnera, and starvation on wing dimorphism in English grain aphid, Sitobion avenae (F.) (Homoptera: Aphididae)

    USDA-ARS?s Scientific Manuscript database

    Wing dimorphism in aphids can be affected by multiple cues including both biotic (nutrition, crowding, interspecific interactions, the presence of natural enemies, maternal and transgenerational effects, and alarm pheromone) and abiotic factors (temperature, humidity, and photoperiod). Virtually al...

  17. Temperature structure of the Uranian upper atmosphere

    NASA Technical Reports Server (NTRS)

    Elliot, J. L.; Dunham, E.

    1979-01-01

    The temperature structure of the upper atmosphere of Uranus at two locations on the planet was determined from observations of the occultation of the star SAO158687 by Uranus on 10 March 1977, carried out at the Kuiper Airborne Observatory. The temperature-pressure relationships obtained from the immersion and emersion data for 7280 A channel show peak-to-peak variations of 45 K for immersion and 35 K for emersion. The mean temperature for both immersion and emersion profiles is about 100 K, which shows that Uranus has a temperature inversion between 0.001 mbar and the 100 mbar level probed by IR measurements. Both profiles show wavelike temperature variations, which may be due to dynamical or photochemical processes.

  18. Temperature determination of shock layer using spectroscopic techniques

    NASA Technical Reports Server (NTRS)

    Akundi, Murty A.

    1989-01-01

    Shock layer temperature profiles are obtained through analysis of radiation from shock layers produced by a blunt body inserted in an arc jet flow. Spectral measurements of N2(+) have been made at 0.5 inch, 1.0 inch, and 1.4 inches from the blunt body. A technique is developed to measure the vibrational and rotational temperatures of N2(+). Temperature profiles from the radiation layers show a high temperature near the shock front and decreasing temperature near the boundary layer. Precise temperature measurements could not be made using this technique due to the limited resolution. Use of a high resolution grating will help to make a more accurate temperature determination. Laser induced fluorescence technique is much better since it gives the scope for selective excitation and a better spacial resolution.

  19. A new temperature profiling probe for investigating groundwater-surface water interaction

    USGS Publications Warehouse

    Naranjo, Ramon C.; Robert Turcotte,

    2015-01-01

    Measuring vertically nested temperatures at the streambed interface poses practical challenges that are addressed here with a new discrete subsurface temperature profiling probe. We describe a new temperature probe and its application for heat as a tracer investigations to demonstrate the probe's utility. Accuracy and response time of temperature measurements made at 6 discrete depths in the probe were analyzed in the laboratory using temperature bath experiments. We find the temperature probe to be an accurate and robust instrument that allows for easily installation and long-term monitoring in highly variable environments. Because the probe is inexpensive and versatile, it is useful for many environmental applications that require temperature data collection for periods of several months in environments that are difficult to access or require minimal disturbance.

  20. [Self-perception and life satisfaction in video game addiction in young adolescents (11-14 years old)].

    PubMed

    Gaetan, S; Bonnet, A; Pedinielli, J-L

    2012-12-01

    Video games are part of our society's major entertainments. This is now a global industry that covers the preferential activity of adolescents. But for some, the practice goes beyond a game and becomes an addictive functioning. Clinical practice is then faced with a new problem. It is important to understand the special bond that develops between a player and his/her video game in order to understand the addictive process. The game consists of a virtual world, a graphical construction that is a simulation of reality and which reinvents the laws that govern it. It also consists of a character embodied by the player who controls it: the avatar. Through the virtual world and avatar, the game offers the player a virtual personification that matches his/her expectations and projected ideal. The avatar allows the subject to compensate, or even to modify some aspects of the Self and thus enhance his/her perception of him/herself; the virtual life become more satisfying than real life. The aim of this research is to propose, from the study of the relationship between psychosocial variables (self-perception and life satisfaction) and the adolescent's practice of video games, elements of construction of an explanatory model of video gambling addiction. The population of this research is composed of 74 adolescents aged 11-14 years (m(age)=12.78 and SD=0.921). Fourteen are identified as addicted to video games by the results of the Game Addiction Scale. The quantitative methodology allows measurement of the different psychosocial variables which appear important in the addictive process. The instruments used are: the Game Addiction Scale, the Self-Perception Profile and the Satisfaction with Life Scale. The results show that adolescents addicted to video games see their virtual and current Self as being less proficient than other teenagers. Furthermore, teenagers addicted to video games see their virtual Self as more proficient and adapted to the environment than their current Self. Moreover, adolescents addicted perceive their lives as less satisfying than others'. Hence, virtual life is perceived as more satisfying than real life among teenagers addicted to video games. Finally, this virtual experience is thus one of the factors that explain the addiction to video games. Through the game, the teenager can "live" a new version of him/herself, becoming secondarily alienating. The virtual world supplants real life and becomes the source of a clash of identity. Copyright © 2012 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

  1. Profiles of second- to fourth-order moments of turbulent temperature fluctuations in the convective boundary layer: first measurements with rotational Raman lidar

    NASA Astrophysics Data System (ADS)

    Behrendt, A.; Wulfmeyer, V.; Hammann, E.; Muppa, S. K.; Pal, S.

    2015-05-01

    The rotational Raman lidar (RRL) of the University of Hohenheim (UHOH) measures atmospheric temperature profiles with high resolution (10 s, 109 m). The data contain low-noise errors even in daytime due to the use of strong UV laser light (355 nm, 10 W, 50 Hz) and a very efficient interference-filter-based polychromator. In this paper, the first profiling of the second- to fourth-order moments of turbulent temperature fluctuations is presented. Furthermore, skewness profiles and kurtosis profiles in the convective planetary boundary layer (CBL) including the interfacial layer (IL) are discussed. The results demonstrate that the UHOH RRL resolves the vertical structure of these moments. The data set which is used for this case study was collected in western Germany (50°53'50.56'' N, 6°27'50.39'' E; 110 m a.s.l.) on 24 April 2013 during the Intensive Observations Period (IOP) 6 of the HD(CP)2 (High-Definition Clouds and Precipitation for advancing Climate Prediction) Observational Prototype Experiment (HOPE). We used the data between 11:00 and 12:00 UTC corresponding to 1 h around local noon (the highest position of the Sun was at 11:33 UTC). First, we investigated profiles of the total noise error of the temperature measurements and compared them with estimates of the temperature measurement uncertainty due to shot noise derived with Poisson statistics. The comparison confirms that the major contribution to the total statistical uncertainty of the temperature measurements originates from shot noise. The total statistical uncertainty of a 20 min temperature measurement is lower than 0.1 K up to 1050 m a.g.l. (above ground level) at noontime; even for single 10 s temperature profiles, it is smaller than 1 K up to 1020 m a.g.l. Autocovariance and spectral analyses of the atmospheric temperature fluctuations confirm that a temporal resolution of 10 s was sufficient to resolve the turbulence down to the inertial subrange. This is also indicated by the integral scale of the temperature fluctuations which had a mean value of about 80 s in the CBL with a tendency to decrease to smaller values towards the CBL top. Analyses of profiles of the second-, third-, and fourth-order moments show that all moments had peak values in the IL around the mean top of the CBL which was located at 1230 m a.g.l. The maximum of the variance profile in the IL was 0.39 K2 with 0.07 and 0.11 K2 for the sampling error and noise error, respectively. The third-order moment (TOM) was not significantly different from zero in the CBL but showed a negative peak in the IL with a minimum of -0.93 K3 and values of 0.05 and 0.16 K3 for the sampling and noise errors, respectively. The fourth-order moment (FOM) and kurtosis values throughout the CBL were not significantly different to those of a Gaussian distribution. Both showed also maxima in the IL but these were not statistically significant taking the measurement uncertainties into account. We conclude that these measurements permit the validation of large eddy simulation results and the direct investigation of turbulence parameterizations with respect to temperature.

  2. Gravity wave momentum flux estimation from CRISTA satellite data

    NASA Astrophysics Data System (ADS)

    Ern, M.; Preusse, P.; Alexander, M. J.; Offermann, D.

    2003-04-01

    Temperature altitude profiles measured by the CRISTA satellite were analyzed for gravity waves (GWs). Amplitudes, vertical and horizontal wavelengths of GWs are retrieved by applying a combination of maximum entropy method (MEM) and harmonic analysis (HA) to the temperature height profiles and subsequently comparing the so retrieved GW phases of adjacent altitude profiles. From these results global maps of the absolute value of the vertical flux of horizontal momentum have been estimated. Significant differences between distributions of the temperature variance and distributions of the momentum flux exist. For example, global maps of the momentum flux show a pronounced northward shift of the equatorial maximum whereas temperature variance maps of the tropics/subtropics are nearly symmetric with respect to the equator. This indicates the importance of the influence of horizontal and vertical wavelength distribution on global structures of the momentum flux.

  3. A Technique for Transient Thermal Testing of Thick Structures

    NASA Technical Reports Server (NTRS)

    Horn, Thomas J.; Richards, W. Lance; Gong, Leslie

    1997-01-01

    A new open-loop heat flux control technique has been developed to conduct transient thermal testing of thick, thermally-conductive aerospace structures. This technique uses calibration of the radiant heater system power level as a function of heat flux, predicted aerodynamic heat flux, and the properties of an instrumented test article. An iterative process was used to generate open-loop heater power profiles prior to each transient thermal test. Differences between the measured and predicted surface temperatures were used to refine the heater power level command profiles through the iteration process. This iteration process has reduced the effects of environmental and test system design factors, which are normally compensated for by closed-loop temperature control, to acceptable levels. The final revised heater power profiles resulted in measured temperature time histories which deviated less than 25 F from the predicted surface temperatures.

  4. Eigenmode electric field profiles in cylindrical plasmas

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

    Litwin, C.; Hershkowitz, N.

    Electric field profiles of plasma column eigenmodes in the ion-cyclotron range of frequencies are discussed. Step and parabolic density profiles are compared. The role of temperature and Alfven resonance is analyzed.

  5. An Orbital "Virtual Radar" from TRMM Passive Microwave and Lightning Observations

    NASA Technical Reports Server (NTRS)

    Boccippio, Dennis J.

    2004-01-01

    The retrieval of vertical structure from joint passive microwave and lightning observations is demonstrated. Three years of data from the TRMM (Tropical Rainfall Measuring Mission) are used as a training dataset for regression and classification neural networks; the TMI (TRMM Microwave Imager) and LIS (Lightning Imaging Sensor) provide the inputs, the PR (Precipitation Radar) provides the training targets. Both vertical reflectivity profile categorization (into 9 convective, 7 stratiform, 2 mixed and 6 anvil types) and geophysical parameters (surface rainfall, vertically integrated liquid (VIL), ice water content (IWC) and echo tops) are retrieved. Retrievals are successful over both land and ocean surfaces. The benefit of using lightning observations as inputs to these retrievals is quantitatively demonstrated; lightning essentially provides an additional convective/stratiform discriminator, and is most important for isolation of midlevel (tops in the mixed phase region) convective profile types (this is because high frequency passive microwave observations already provide good convective/stratiform discrimination for deep convective profiles). This is highly relevant as midlevel convective profiles account for an extremely large fraction of tropical rainfall, and yet are most difficult to discriminate from comparable-depth stratiform profile types using passive microwave observations alone.

  6. Simultaneous Retrieval of Temperature, Water Vapor and Ozone Atmospheric Profiles from IASI: Compression, De-noising, First Guess Retrieval and Inversion Algorithms

    NASA Technical Reports Server (NTRS)

    Aires, F.; Rossow, W. B.; Scott, N. A.; Chedin, A.; Hansen, James E. (Technical Monitor)

    2001-01-01

    A fast temperature water vapor and ozone atmospheric profile retrieval algorithm is developed for the high spectral resolution Infrared Atmospheric Sounding Interferometer (IASI) space-borne instrument. Compression and de-noising of IASI observations are performed using Principal Component Analysis. This preprocessing methodology also allows, for a fast pattern recognition in a climatological data set to obtain a first guess. Then, a neural network using first guess information is developed to retrieve simultaneously temperature, water vapor and ozone atmospheric profiles. The performance of the resulting fast and accurate inverse model is evaluated with a large diversified data set of radiosondes atmospheres including rare events.

  7. Stress studies in EFG

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A computer code which can account for plastic deformation effects on stress generated in silicon sheet grown at high speeds is fully operative. Stress and strain rate distributions are presented for two different sheet temperature profiles. The calculations show that residual stress levels are very sensitive to details of the cooling profile in a sheet with creep. Experimental work has been started in several areas to improve understanding of ribbon temperature profiles and stress distributions associated with a 10 cm wide ribbon cartridge system.

  8. Review of Nimbus-5 Microwave Spectrometer results. [atmospheric temperature profile measurement

    NASA Technical Reports Server (NTRS)

    Staelin, D. H.

    1974-01-01

    Nimbus-E Microwave Spectrometer (NEMS) data are analyzed, especially those obtained from the 53.65, 54.9, and 58.8 GHz channels, corresponding to sensing at 4, 11, and 18 km respectively. The observations permit highly precise horizontal temperature profiles to be established and are hardly affected by clouds. The sensings of the 54.9 GHz channel unambiguously delineate wave structure on the equator. Horizontal water vapor profiles are derived from the 22.235 and 31.4 GHz channel data.

  9. Using Hierarchical Virtual Screening To Combat Drug Resistance of the HIV-1 Protease.

    PubMed

    Li, Nan; Ainsworth, Richard I; Ding, Bo; Hou, Tingjun; Wang, Wei

    2015-07-27

    Human immunodeficiency virus (HIV) protease inhibitors (PIs) are important components of highly active anti-retroviral therapy (HAART) that block the catalytic site of HIV protease, thus preventing maturation of the HIV virion. However, with two decades of PI prescriptions in clinical practice, drug-resistant HIV mutants have now been found for all of the PI drugs. Therefore, the continuous development of new PI drugs is crucial both to combat the existing drug-resistant HIV strains and to provide treatments for future patients. Here we purpose an HIV PI drug design strategy to select candidate PIs with binding energy distributions dominated by interactions with conserved protease residues in both wild-type and various drug-resistant mutants. On the basis of this strategy, we have constructed a virtual screening pipeline including combinatorial library construction, combinatorial docking, MM/GBSA-based rescoring, and reranking on the basis of the binding energy distribution. We have tested our strategy on lopinavir by modifying its two functional groups. From an initial 751 689 candidate molecules, 18 candidate inhibitors were selected using the pipeline for experimental validation. IC50 measurements and drug resistance predictions successfully identified two ligands with both HIV protease inhibitor activity and an improved drug resistance profile on 2382 HIV mutants. This study provides a proof of concept for the integration of MM/GBSA energy analysis and drug resistance information at the stage of virtual screening and sheds light on future HIV drug design and the use of virtual screening to combat drug resistance.

  10. Prospective performance evaluation of selected common virtual screening tools. Case study: Cyclooxygenase (COX) 1 and 2.

    PubMed

    Kaserer, Teresa; Temml, Veronika; Kutil, Zsofia; Vanek, Tomas; Landa, Premysl; Schuster, Daniela

    2015-01-01

    Computational methods can be applied in drug development for the identification of novel lead candidates, but also for the prediction of pharmacokinetic properties and potential adverse effects, thereby aiding to prioritize and identify the most promising compounds. In principle, several techniques are available for this purpose, however, which one is the most suitable for a specific research objective still requires further investigation. Within this study, the performance of several programs, representing common virtual screening methods, was compared in a prospective manner. First, we selected top-ranked virtual screening hits from the three methods pharmacophore modeling, shape-based modeling, and docking. For comparison, these hits were then additionally predicted by external pharmacophore- and 2D similarity-based bioactivity profiling tools. Subsequently, the biological activities of the selected hits were assessed in vitro, which allowed for evaluating and comparing the prospective performance of the applied tools. Although all methods performed well, considerable differences were observed concerning hit rates, true positive and true negative hits, and hitlist composition. Our results suggest that a rational selection of the applied method represents a powerful strategy to maximize the success of a research project, tightly linked to its aims. We employed cyclooxygenase as application example, however, the focus of this study lied on highlighting the differences in the virtual screening tool performances and not in the identification of novel COX-inhibitors. Copyright © 2015 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

  11. Interpreting Observations of Large-Scale Traveling Ionospheric Disturbances by Ionospheric Sounders

    NASA Astrophysics Data System (ADS)

    Pederick, L. H.; Cervera, M. A.; Harris, T. J.

    2017-12-01

    From July to October 2015, the Australian Defence Science and Technology Group conducted an experiment during which a vertical incidence sounder (VIS) was set up at Alice Springs Airport. During September 2015 this VIS observed the passage of many large-scale traveling ionospheric disturbances (TIDs). By plotting the measured virtual heights across multiple frequencies as a function of time, the passage of the TID can be clearly displayed. Using this plotting method, we show that all the TIDs observed during the campaign by the VIS at Alice Springs show an apparent downward phase progression of the crests and troughs. The passage of the TID can be more clearly interpreted by plotting the true height of iso-ionic contours across multiple plasma frequencies; the true heights can be obtained by inverting each ionogram to obtain an electron density profile. These plots can be used to measure the vertical phase speed of a TID and also reveal a time lag between events seen in true height compared to virtual height. To the best of our knowledge, this style of analysis has not previously been applied to other swept-frequency sounder observations. We develop a simple model to investigate the effect of the passage of a large-scale TID on a VIS. The model confirms that for a TID with a downward vertical phase progression, the crests and troughs will appear earlier in virtual height than in true height and will have a smaller apparent speed in true height than in virtual height.

  12. Validation of science virtual test to assess 8th grade students' critical thinking on living things and environmental sustainability theme

    NASA Astrophysics Data System (ADS)

    Rusyati, Lilit; Firman, Harry

    2017-05-01

    This research was motivated by the importance of multiple-choice questions that indicate the elements and sub-elements of critical thinking and implementation of computer-based test. The method used in this research was descriptive research for profiling the validation of science virtual test to measure students' critical thinking in junior high school. The participant is junior high school students of 8th grade (14 years old) while science teacher and expert as the validators. The instrument that used as a tool to capture the necessary data are sheet of an expert judgment, sheet of legibility test, and science virtual test package in multiple choice form with four possible answers. There are four steps to validate science virtual test to measure students' critical thinking on the theme of "Living Things and Environmental Sustainability" in 7th grade Junior High School. These steps are analysis of core competence and basic competence based on curriculum 2013, expert judgment, legibility test and trial test (limited and large trial test). The test item criterion based on trial test are accepted, accepted but need revision, and rejected. The reliability of the test is α = 0.747 that categorized as `high'. It means the test instruments used is reliable and high consistency. The validity of Rxy = 0.63 means that the validity of the instrument was categorized as `high' according to interpretation value of Rxy (correlation).

  13. Well-posed two-temperature constitutive equations for stable dense fluid shock waves using molecular dynamics and generalizations of Navier-Stokes-Fourier continuum mechanics.

    PubMed

    Hoover, Wm G; Hoover, Carol G

    2010-04-01

    Guided by molecular dynamics simulations, we generalize the Navier-Stokes-Fourier constitutive equations and the continuum motion equations to include both transverse and longitudinal temperatures. To do so we partition the contributions of the heat transfer, the work done, and the heat flux vector between the longitudinal and transverse temperatures. With shockwave boundary conditions time-dependent solutions of these equations converge to give stationary shockwave profiles. The profiles include anisotropic temperature and can be fitted to molecular dynamics results, demonstrating the utility and simplicity of a two-temperature description of far-from-equilibrium states.

  14. Climatology and trends of mesospheric (58-90) temperatures based upon 1982-1986 SME limb scattering profiles

    NASA Technical Reports Server (NTRS)

    Clancy, R. Todd; Rusch, David W.

    1989-01-01

    Atmospheric temperature profiles for the altitude range 58-90 km were calculated using data on global UV limb radiances from the SME satellite. The major elements of this climatology include a high vertical resolution (about 4 km) and the coverage of the 70-90 km altitude region. The analysis of this extensive data set provides a global definition of mesospheric-lower thermospheric temperature trends over the 1982-1986 period. The observations suggest a pattern of 1-2 K/year decreases in temperatures at 80-90-km altitudes accompanied by 0.5-1.5 K/year increases in temperatures at 65-80-km altitudes.

  15. Seasonal Variations in the CO Line Profile and the Retrieved Thermal/Pressure Structures in the Atmosphere of Mars

    NASA Astrophysics Data System (ADS)

    Khayat, Alain; Villanueva, G. L.; Mumma, M. J.; Riesen, T. E.; Tokunaga, A. T.

    2013-10-01

    We report retrievals of temperature vertical profiles up to 100 km over Tharsis and Syrtis regions on Mars obtained by inverting the strong rotational (3-2) line of carbon monoxide (CO) at 346 GHz. Observations of CO were made from mid Northern Spring to early Northern Summer on Mars (Ls= 36°-108°, 23 Nov, 2011 - 13 May, 2012) using the Caltech Submillimeter Observatory's (CSO) high-resolution heterodyne receiver (Barney) on top of Mauna Kea, Hawai'i. The temperature profiles were derived using our radiative transfer model that considers the latest spectroscopic constants for CO collisionally broadened by CO2. We observe notable changes of the line profile for different dates, which are directly related to seasonal variations in the thermal/pressure structure of the atmosphere. The seasonal variability of the martian CO line profile, the extracted temperature profiles, and comparisons with modeled profiles from the Mars Climate Database (Lewis et al, 1999) will be presented. We gratefully acknowledge support from the NASA Planetary Astronomy Program , NASA Astrobiology Institute, Planetary Atmospheres programs. This material is based upon work at the Caltech Submillimeter Observatory, which is operated by the California Institute of Technology under cooperative agreement with the National Science Foundation, grant number AST-0838261.

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

    Gitti, Myriam; Nulsen, Paul E. J.; David, Laurence P.

    We present the results of a Chandra study of the Hydra A galaxy cluster, where a powerful active galactic nucleus (AGN) outburst created a large-scale cocoon shock. We investigated possible azimuthal variations in shock strength and shape, finding indications for a weak shock with a Mach number in the range {approx}1.2-1.3. We measured the temperature change across the shock front. However, the detection of a temperature rise in the regions immediately inside of the front is complicated by the underlying temperature profile of the cluster atmosphere. We measured the global temperature profile of the cluster up to 700 kpc, whichmore » represents the farthest measurement obtained with Chandra for this cluster. A 'plateau' in the temperature profile in the range {approx}70-150 kpc indicates the presence of cool gas, which is likely the result of uplift of material by the AGN outburst. After masking the cool filaments visible in the hardness ratio map, the plateau disappears and the temperature profile recovers a typical shape with a peak around 190 kpc, just inside the shock front. However, it is unlikely that such a temperature feature is produced by the shock as it is consistent with the general shape of the temperature profiles observed for relaxed galaxy clusters. We studied the spectral properties of the cool filaments finding evidence that {approx}10{sup 11} M{sub sun} of low-entropy material has been dredged up by the rising lobes from the central 30 kpc to the observed current position of 75-150 kpc. The energy required to lift the cool gas is {approx}> 2.2 x 10{sup 60} erg, which is comparable to the work required to inflate the cavities and is {approx}25% of the total energy of the large-scale shock. Our results show that the AGN feedback in Hydra A is acting not only by directly heating the gas, but also by removing a substantial amount of potential fuel for the supermassive black hole.« less

  17. Automated Protocol for Large-Scale Modeling of Gene Expression Data.

    PubMed

    Hall, Michelle Lynn; Calkins, David; Sherman, Woody

    2016-11-28

    With the continued rise of phenotypic- and genotypic-based screening projects, computational methods to analyze, process, and ultimately make predictions in this field take on growing importance. Here we show how automated machine learning workflows can produce models that are predictive of differential gene expression as a function of a compound structure using data from A673 cells as a proof of principle. In particular, we present predictive models with an average accuracy of greater than 70% across a highly diverse ∼1000 gene expression profile. In contrast to the usual in silico design paradigm, where one interrogates a particular target-based response, this work opens the opportunity for virtual screening and lead optimization for desired multitarget gene expression profiles.

  18. Retrieving cloudy atmosphere parameters from RPG-HATPRO radiometer data

    NASA Astrophysics Data System (ADS)

    Kostsov, V. S.

    2015-03-01

    An algorithm for simultaneously determining both tropospheric temperature and humidity profiles and cloud liquid water content from ground-based measurements of microwave radiation is presented. A special feature of this algorithm is that it combines different types of measurements and different a priori information on the sought parameters. The features of its use in processing RPG-HATPRO radiometer data obtained in the course of atmospheric remote sensing experiments carried out by specialists from the Faculty of Physics of St. Petersburg State University are discussed. The results of a comparison of both temperature and humidity profiles obtained using a ground-based microwave remote sensing method with those obtained from radiosonde data are analyzed. It is shown that this combined algorithm is comparable (in accuracy) to the classical method of statistical regularization in determining temperature profiles; however, this algorithm demonstrates better accuracy (when compared to the method of statistical regularization) in determining humidity profiles.

  19. Transport Studies in Alcator C-Mod ITB Plasmas

    NASA Astrophysics Data System (ADS)

    Fiore, C. L.; Bonoli, P. T.; Ernst, D.; Greenwald, M. J.; Ince-Cushman, A.; Lin, L.; Marmar, E. S.; Porkolab, M.; Rice, J. E.; Wukitch, S.; Rowan, W.; Bespamyatnov, I.; Phillips, P.

    2008-11-01

    Internal transport barriers occur in C-Mod plasmas that have off-axis ICRF heating and also in Ohmic H-mode plasmas. These ITBs are marked by highly peaked density and pressure profiles, as they rely on a reduction of particle and thermal flux in the barrier region which allows the neoclassical pinch to peak the central density without reducing the central temperature. Enhancement of several core diagnostics has resulted in increased understanding of C-Mod ITBs. Ion temperature profile measurements have been obtained using an innovative design for x-ray crystal spectrometry and clearly show a barrier forming in the ion temperature profile. The phase contrast imaging (PCI) provides limited localization of the ITB related fluctuations that increase in strength as the central density increases. Simulation of triggering conditions, integrated simulations with fluctuation measurements, parametric studies, and transport implications of fully ionized boron impurity profiles in the plasma are under study. A summary of these results will be presented.

  20. Variations in Temperature at the Base of the Lithosphere Beneath the Archean Superior Province, Canada

    NASA Astrophysics Data System (ADS)

    Mareschal, J.; Jaupart, C. P.

    2013-12-01

    Most of the variations in surface heat flux in stable continents are caused by variations in crustal heat production, with an almost uniform heat flux at the base of the crust ( 15+/-3 mW/m2). Such relatively small differences in Moho heat flux cannot be resolved by heat flow data alone, but they lead to important lateral variations in lithospheric temperatures and thicknesses. In order to better constrain temperatures in the lower lithosphere, we have combined surface heat flow and heat production data from the southern Superior Province in Canada with vertical shear wave velocity profiles obtained from surface wave inversion. We use the Monte-Carlo method to generate lithospheric temperature profiles from which shear wave velocity can be calculated for a given mantle composition. We eliminate thermal models which yield lithospheric and sub-lithospheric velocities that do not fit the shear wave velocity profile. Surface heat flux being constrained, the free parameters of the thermal model are: the mantle heat flux, the mantle heat production, the crustal differentiation index (ratio of surface to bulk crustal heat production) and the temperature of the mantle isentrope. Two conclusions emerge from this study. One is that, for some profiles, the vertical variations in shear wave velocities cannot be accounted for by temperature alone but also require compositional changes within the lithosphere. The second is that there are long wavelength horizontal variations in mantle temperatures (~80-100K) at the base of the lithosphere and in the mantle below

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