Science.gov

Sample records for heat transmission

  1. Transient analysis of heat transmission systems

    NASA Astrophysics Data System (ADS)

    Phetteplace, G. E.

    1981-12-01

    This report develops a method of analysis for heat transmission systems operating under district heating load conditions. The method accounts for the effects of heat source and load characteristics. The use of thermal energy storage systems is outlined and advantages are given. The transmission model itself considers the following technical aspects: (1) frictional pressure losses in piping system, (2) pump characteristics, (3) pump driver characteristics, and (4) heat losses from the buried piping. The capital costs considered are the piping system and necessary pumps. Operation and maintenance costs include cost of heat loss and cost of pumping energy input. Allowances are also made for system maintenance and repair over the assumed lifetime.

  2. Heat Transmission Properties of Insulating and Building Materials

    National Institute of Standards and Technology Data Gateway

    SRD 81 NIST Heat Transmission Properties of Insulating and Building Materials (Web, free access)   NIST has accumulated a valuable and comprehensive collection of thermal conductivity data. Version 1.0 of the database includes data for over 2000 measurements, covering several categories of materials including concrete, fiberboard, plastics, thermal insulation, and rubber.

  3. Specific features of waveguide heating due to transmission of high-power microwave signals

    NASA Astrophysics Data System (ADS)

    Kudryavtsev, I. V.; Gotselyuk, O. B.; Novikov, E. S.; Demin, V. G.

    2017-01-01

    Waveguide heating due to transmission of microwave signals is studied. Mathematical models are developed to evaluate heat liberation, and differential equations of thermal balance are derived with allowance for different working conditions of waveguides. The results prove the necessity of the further study of the effect of heat liberation in waveguides on strength and functional characteristics.

  4. Implementation of transmission functions for an optimized three-terminal quantum dot heat engine.

    PubMed

    Schiegg, Christian H; Dzierzawa, Michael; Eckern, Ulrich

    2017-03-01

    We consider two modifications of a recently proposed three-terminal quantum dot heat engine. First, we investigate the necessity of the thermalization assumption, namely that electrons are always thermalized by inelastic processes when traveling across the cavity where the heat is supplied. Second, we analyze various arrangements of tunneling-coupled quantum dots in order to implement a transmission function that is superior to the Lorentzian transmission function of a single quantum dot. We show that the maximum power of the heat engine can be improved by about a factor of two, even for a small number of dots, by choosing an optimal structure.

  5. Implementation of transmission functions for an optimized three-terminal quantum dot heat engine

    NASA Astrophysics Data System (ADS)

    Schiegg, Christian H.; Dzierzawa, Michael; Eckern, Ulrich

    2017-03-01

    We consider two modifications of a recently proposed three-terminal quantum dot heat engine. First, we investigate the necessity of the thermalization assumption, namely that electrons are always thermalized by inelastic processes when traveling across the cavity where the heat is supplied. Second, we analyze various arrangements of tunneling-coupled quantum dots in order to implement a transmission function that is superior to the Lorentzian transmission function of a single quantum dot. We show that the maximum power of the heat engine can be improved by about a factor of two, even for a small number of dots, by choosing an optimal structure.

  6. Broadband asymmetric acoustic transmission in a single medium by an array of heat sources

    NASA Astrophysics Data System (ADS)

    Guan, Yi-Jun; Sun, Hong-Xiang; Xia, Jian-Ping; Yuan, Shou-Qi

    2017-04-01

    We report the realization of a broadband asymmetric acoustic transmission with six different-temperature heat sources in air. This exotic effect arises from the desired refractive index in propagation paths induced from heat sources of different temperatures and asymmetrical distribution, which avoids acoustic impedance differences between the heat sources and air and has no reflection energy loss. In addition, the influence of the viscosity of air, the thermal convection, and the temperature and length of the heat sources on the asymmetric transmission effect is investigated in detail. The results show that the proposed device has the advantages of broad bandwidth, high transmission contrast, and simple structure, which enable it to provide more schemes for sound manipulation. It has excellent potential applications in acoustic devices.

  7. Heat transmission between a profiled nanowire and a thermal bath

    SciTech Connect

    Blanc, Christophe; Heron, Jean-Savin; Fournier, Thierry; Bourgeois, Olivier

    2014-07-28

    Thermal transport through profiled and abrupt contacts between a nanowire and a reservoir has been investigated by thermal conductance measurements. It is demonstrated that above 1 K the transmission coefficients are identical between abrupt and profiled junctions. This shows that the thermal transport is principally governed by the nanowire itself rather than by the resistance of the thermal contact. These results are perfectly compatible with the previous theoretical models. The thermal conductance measured at sub-Kelvin temperatures is discussed in relation to the universal value of the quantum of thermal conductance.

  8. A comparison of analytical approaches for wellbore heat transmission in layered formations

    SciTech Connect

    Wu, Yu-Shu.

    1988-08-01

    This report presents an analytical method for determining wellbore heat transmission during liquid or gas flow along the tubing. The mathematical model describes the heat transfer between the flowing fluid in the wellbore and in the surrounding formation as one whole physical system. The transient heat transfer equations in the two regions with coupling at the sandface are solved simultaneously. Non-homogeneous formations are treated which consist of several layers with different physical properties and arbitrary initial temperature distributions in the vertical direction. Closed form analytical solutions are obtained in real space and in Laplace space, which can be used to calculate the temperature distribution along the wellbore and in the formation, and to evaluate heat transfer rate and cumulative heat exchange between wellbore and formation. A more accurate formula is given for the widely-used transient heat conduction function f(t{sub D}) of thermal resistance. 14 refs., 12 figs., 1 tab.

  9. Parvovirus B19 transmission by heat-treated clotting factor concentrates.

    PubMed

    Blümel, Johannes; Schmidt, Ivo; Effenberger, Wolfgang; Seitz, Holger; Willkommen, Hannelore; Brackmann, Hans Herrmann; Löwer, Johannes; Eis-Hübinger, Anna Maria

    2002-11-01

    Human parvovirus B19 (B19) DNA can be frequently detected in plasma-derived coagulation factor concentrates. The production of some clotting factor products includes heat treatment steps for virus inactivation, but the effectiveness of such steps for B19 inactivation is unclear. Moreover, detailed transmission case reports including DNA sequence analysis and quantification of B19 DNA from contaminated heat-treated blood components have not been provided so far. Therefore, the correlation between B19 DNA in blood components and infectivity remains unclear. Asymptomatic B19 infections of two patients with hemophilia A were detected by anti-B19 seroconversion after administration of B19-contaminated heat-treated clotting factors. The suitability of nucleic acid sequence analysis for confirmation of B19 transmission was investigated. Furthermore, the B19 DNA level in blood components was determined and the drug administration was reviewed to calculate the amount of inoculated B19 DNA. Both B19 transmissions from clotting factor products could be confirmed by identical nucleic acid sequences of virus DNA from patients and blood components while sequences from unrelated controls could be differentiated. One patient received, for 4 days, a total of 180 mL vapor heat-treated prothrombin complex concentrate containing 8.6 x 10(6) genome equivalents per mL of B19 DNA. The other patient received 966 mL of low-contamination (4.0 x 10(3) genome equivalents/mL) dry heat-treated FVIII concentrate over a period of 52 days. B19 transmissions can be confirmed by nucleic acid sequencing. However, due to the low variability of the B19 genome, a large part of the B19 genome must be analyzed. The transmissions show that the applied heat treatment procedures were not sufficient to inactivate B19 completely.

  10. Local heating in biological body using wireless transmission power into small resonant devices driven by MRI

    NASA Astrophysics Data System (ADS)

    Nakano, Akitsugu; Nikawa, Yoshio

    2016-11-01

    MRI is applying an electromagnetic (EM) wave for imaging. In application of EM waves, the heating effect will be applicable such as hyperthermia for cancer treatment. This paper examines heating effects of the small resonant devices using Radio Frequency (RF) signal generated by MRI. A small resonant device which is inserted in the body absorbs RF power, and its temperature can be increased. By this method, better heating efficiency and higher transmission properties will be realized. With using a simulator, transmission properties from an RF coil of the MRI to the small resonant device including signal power density and the SAR pattern are evaluated. Transmission properties can be obtained as a parameter of winding number of solenoid coil. In addition, the small resonant device is made on a condition as same as simulation and performed the experiments and measured the temperature rise using an optical fiber thermometer. The experimental results agree well with the simulation. From the results, it is found that the small resonant device is applicable for heating in human body.

  11. Coastal ocean optical influences on solar transmission and radiant heating rate

    NASA Astrophysics Data System (ADS)

    Chang, Grace C.; Dickey, Tommy D.

    2004-01-01

    An extensive set of physical and optical measurements is utilized to characterize the processes and quantify parameters that contribute to the variability of solar transmission, sea surface albedo, and radiant heating rate (RHR). This study is among the first to utilize multidisciplinary observations coupled with radiative transfer simulations to investigate the impact of optical properties on solar transmission, albedo, and heating in nearshore coastal waters. The data were collected from a shallow-water coastal mooring as part of the Hyperspectral Coastal Ocean Dynamics Experiment (HyCODE) in summer 2001. Over the 41-day time series, the average loss in solar radiation was 274 W m-2 for mean surface radiation of 365 W m-2 (average solar transmission of 21%). Quantitative coherence and principle component analyses suggest that cloud cover, chlorophyll concentration (Chl), and colored dissolved organic matter (CDOM) have the greatest impacts on solar transmission variability on timescales of ˜1 week. Radiative transfer simulations show that Chl, absorption, and attenuation have the most significant impact on solar transmission, whereas solar angle and cloud cover greatly influence albedo.

  12. Thermographic determination of the sheath heat transmission coefficient in a high density plasma

    NASA Astrophysics Data System (ADS)

    van den Berg, M. A.; Bystrov, K.; Pasquet, R.; Zielinski, J. J.; De Temmerman, G.

    2013-07-01

    Experiments were performed in the Pilot-PSI linear plasma device, to determine the sheath heat transmission coefficients in a high recycling regime under various conditions of density (1-20 × 1020 m-3) and plasma composition (H2, Ar, N2) relevant for the ITER divertor plasma. The 2D surface temperature profile on a tungsten surface was measured with high spatial (0.33 mm) and temporal (200 Hz) resolution using an infrared camera. The target heat flux is calculated using a 2D axis-symmetric Ansys model, the heat transfer is determined from target calorimetry. The plasma parameters are measured with a high resolution Thomson scattering system located 17 mm away from the target surface. Radial profiles of the sheath heat transmission factors can thus be determined. Preliminary results show that γ varies between 4 and 40 depending on the plasma conditions and composition. The value derived from the heat flux calculated with Ansys is significantly lower than theory predicts.

  13. In situ transmission electron microscopy of individual carbon nanotetrahedron/nanoribbon structures in Joule heating

    SciTech Connect

    Masuda, Yusuke; Yoshida, Hideto; Takeda, Seiji; Kohno, Hideo

    2014-08-25

    Collapse of a carbon nanotube results in the formation of a nanoribbon, and a switching of the collapse direction yields a nanotetrahedron in the middle of a nanoribbon. Here, we report in-situ transmission electron microscopy observations of the behavior of carbon nanotetrahedron/nanoribbon structures during Joule heating to reveal their thermal stability. In addition, we propose that the observed process is related to the formation process of the structure.

  14. Interplay of electron heating and saturable absorption in ultrafast extreme ultraviolet transmission of condensed matter

    NASA Astrophysics Data System (ADS)

    Di Cicco, Andrea; Hatada, Keisuke; Giangrisostomi, Erika; Gunnella, Roberto; Bencivenga, Filippo; Principi, Emiliano; Masciovecchio, Claudio; Filipponi, Adriano

    2014-12-01

    High intensity pulses obtained by modern extreme ultraviolet (EUV) and x-ray photon sources allows the observation of peculiar phenomena in condensed matter. Experiments performed at the Fermi@Elettra FEL-1 free-electron-laser source at 23.7, 33.5, and 37.5 eV on Al thin films, for an intermediate-fluence range up to about 20 J /cm2, show evidence for a nonmonotonic EUV transmission trend. A decreasing transmission up to about 5 -10 J /cm2 is followed by an increase at higher fluence, associated with saturable absorption effects. The present findings are interpreted within a simplified three-channel model, showing that an account of the interplay between ultrafast electron heating and saturation effects is required to explain the observed transmission trend.

  15. Transmission line component testing for the ITER Ion Cyclotron Heating and Current Drive System

    NASA Astrophysics Data System (ADS)

    Goulding, Richard; Bell, G. L.; Deibele, C. E.; McCarthy, M. P.; Rasmussen, D. A.; Swain, D. W.; Barber, G. C.; Barbier, C. N.; Cambell, I. H.; Moon, R. L.; Pesavento, P. V.; Fredd, E.; Greenough, N.; Kung, C.

    2014-10-01

    High power RF testing is underway to evaluate transmission line components for the ITER Ion Cyclotron Heating and Current Drive System. The transmission line has a characteristic impedance Z0 = 50 Ω and a nominal outer diameter of 305 mm. It is specified to carry up to 6 MW at VSWR = 1.5 for 3600 s pulses, with transient voltages up to 40 kV. The transmission line is actively cooled, with turbulent gas flow (N2) used to transfer heat from the inner to outer conductor, which is water cooled. High voltage and high current testing of components has been performed using resonant lines generating steady state voltages of 35 kV and transient voltages up to 60 kV. A resonant ring, which has operated with circulating power of 6 MW for 1 hr pulses, is being used to test high power, low VSWR operation. Components tested to date include gas barriers, straight sections of various lengths, and 90 degree elbows. Designs tested include gas barriers fabricated from quartz and aluminum nitride, and transmission lines with quartz and alumina inner conductor supports. The latest results will be presented. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.

  16. Tetrahedral node for Transmission-Line Modeling (TLM) applied to Bio-heat Transfer.

    PubMed

    Milan, Hugo F M; Gebremedhin, Kifle G

    2016-12-01

    Transmission-Line Modeling (TLM) is a numerical method used to solve complex and time-domain bio-heat transfer problems. In TLM, parallelepipeds are used to discretize three-dimensional problems. The drawback in using parallelepiped shapes is that instead of refining only the domain of interest, a large additional domain would also have to be refined, which results in increased computational time and memory space. In this paper, we developed a tetrahedral node for TLM applied to bio-heat transfer that does not have the drawback associated with the parallelepiped node. The model includes heat source, blood perfusion, boundary conditions and initial conditions. The boundary conditions could be adiabatic, temperature, heat flux, or convection. The predicted temperature and heat flux were compared against results from an analytical solution and the results agreed within 2% for a mesh size of 69,941 nodes and a time step of 5ms. The method was further validated against published results of maximum skin-surface temperature difference in a breast with and without tumor and the results agreed within 6%. The published results were obtained from a model that used parallelepiped TLM node. An open source software, TLMBHT, was written using the theory developed herein and is available for download free-of-charge. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Assessment of impact of advanced energy transmission fluids on district heating and cooling systems (Phase 1)

    SciTech Connect

    Kasza, K.E.; Chen, M.M.

    1987-09-01

    Argonne National Laboratory (ANL), under sponsorship of the US Department of Energy (DOE) Office of Buildings and Community Systems, has embarked upon a comprehensive, long-range program to develop high-performance advanced energy transmission fluids for use in district heating and cooling (DHC) systems. ANL has the lead technical role in this DOE program. These advanced fluids will substantially reduce flow frictional losses and enhance energy transfer. In system enhancement scoping studies conducted by ANL, the fluids yielded potentially significant upfront capital equipment cost reductions by allowing the use of smaller pipes, pumps, heat exchangers, and storage tanks as well as reductions in operational costs. This report presents the first-phase results of assessment of impact of the advanced fluids on DHC systems. Future reports will focus on assessment of impact on hardware performance, capital eqiupment, and operation costs. 9 refs., 30 figs., 2 tab.

  18. Design of plate directional heat transmission structure based on layered thermal metamaterials

    SciTech Connect

    Sun, L. K.; Yu, Z. F.; Huang, J.

    2016-02-15

    Invisibility cloaks based on transformation optics are often closed structures; however, such a structure limits the kinds of objects that can be placed in the cloak. In this work, we adopt a transformation thermodynamics approach to design an “open cloak”, called a plate directional heat transmission structure, which is capable of guiding heat fluxes to the flank region of the metamaterial device. The most fascinating and unique feature of the device is that the lower surface can remain at a lower temperature compared with the SiO{sub 2} aerogel thermal insulation material. Our results are expected to markedly enhance capabilities in thermal protection, thermal-energy utilization, and domains beyond. In addition to the theoretical analysis, the present design is demonstrated in numerical simulations based on finite element calculations.

  19. Triangular node for Transmission-Line Modeling (TLM) applied to bio-heat transfer.

    PubMed

    Milan, Hugo F M; Gebremedhin, Kifle G

    2016-12-01

    Transmission-Line Modeling (TLM) is a numerical method used to solve complex and time-domain bio-heat transfer problems. In TLM, rectangles are used to discretize two-dimensional problems. The drawback in using rectangular shapes is that instead of refining only the domain of interest, a large additional domain will also be refined in the x and y axes, which results in increased computational time and memory space. In this paper, we developed a triangular node for TLM applied to bio-heat transfer that does not have the drawback associated with the rectangular nodes. The model includes heat source, blood perfusion (advection), boundary conditions and initial conditions. The boundary conditions could be adiabatic, temperature, heat flux, or convection. A matrix equation for TLM, which simplifies the solution of time-domain problems or solves steady-state problems, was also developed. The predicted results were compared against results obtained from the solution of a simplified two-dimensional problem, and they agreed within 1% for a mesh length of triangular faces of 59µm±9µm (mean±standard deviation) and a time step of 1ms. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Sura heating facility transmissions to the CASSIOPE/e-POP satellite

    NASA Astrophysics Data System (ADS)

    James, H. G.; Frolov, V. L.; Andreeva, E. S.; Padokhin, A. M.; Siefring, C. L.

    2017-02-01

    Throughout a nighttime pass of the CASSIOPE satellite at an altitude of about 1300 km above the Sura heating facility, transmission of O-mode radiation from Sura to the enhanced Polar Outflow Probe (e-POP) Radio Receiver Instrument on CASSIOPE was maintained. Also, during this pass, continuous VHF/UHF transmission from the e-POP Coherent Electromagnetic Radio Tomography radio beacon to three coordinated ground receivers in the Sura vicinity was achieved. Tomography of the VHF/UHF received wave data based on total electron content permitted the two-dimensional distribution of ionospheric ambient electron plasma frequency fpe to be determined in the latitude-altitude space between Sura and CASSIOPE. The foF2 values about 0.1 MHz above the Sura pump frequency of 4.3 MHz were measured by the tomography. We examine the question of whether the observations can be explained on the basis of classic propagation in a smooth ionosphere. Tracing of rays from Sura toward CASSIOPE orbital locations finds most rays reflected away from the topside by the patchy ionospheric structure in bottomside fpe. It is concluded that O-mode ducting in underdense field-aligned irregularities is responsible for maintaining the transionospheric transmission across the 2 min pass. O- to Z-mode "radio-window" conversion in the F region bottomside is not required to explain these data.

  1. Solid-State Radio Frequency Plasma Heating Using a Nonlinear Transmission Line

    NASA Astrophysics Data System (ADS)

    Miller, Kenneth; Ziemba, Timothy; Prager, James; Slobodov, Ilia

    2015-11-01

    Radio Frequency heating systems are rarely used by the small-scale validation platform experiments due to the high cost and complexity of these systems, which typically require high power gyrotrons or klystrons, associated power supplies, waveguides and vacuum systems. The cost and complexity of these systems can potentially be reduced with a nonlinear transmission line (NLTL) based system. In the past, NLTLs have lacked a high voltage driver that could produce long duration high voltage pulses with fast rise times at high pulse repetition frequency. Eagle Harbor Technologies, Inc. (EHT) has created new high voltage nanosecond pulser, which combined with NLTL technology will produce a low-cost, fully solid-state architecture for the generation of the RF frequencies (0.5 to 10 GHz) and peak power levels (~ 10 MW) necessary for plasma heating and diagnostic systems for the validation platform experiments within the fusion science community. The proposed system does not require the use of vacuum tube technology, is inherently lower cost, and is more robust than traditional high power RF heating schemes. Design details and initial bench testing results for the new RF system will be presented. This work is supported under DOE Grant # DE-SC0013747.

  2. In situ transmission electron microscopy investigation of the interfacial reaction between Ni and Al during rapid heating in a nanocalorimeter

    SciTech Connect

    Grapes, Michael D. E-mail: david.lavan@nist.gov; LaGrange, Thomas; Reed, Bryan W.; Campbell, Geoffrey H.; Woll, Karsten; LaVan, David A. E-mail: david.lavan@nist.gov; Weihs, Timothy P. E-mail: david.lavan@nist.gov

    2014-11-01

    The Al/Ni formation reaction is highly exothermic and of both scientific and technological significance. In this report, we study the evolution of intermetallic phases in this reaction at a heating rate of 830 K/s. 100-nm-thick Al/Ni bilayers were deposited onto nanocalorimeter sensors that enable the measurement of temperature and heat flow during rapid heating. Time-resolved transmission electron diffraction patterns captured simultaneously with thermal measurements allow us to identify the intermetallic phases present and reconstruct the phase transformation sequence as a function of time and temperature. The results show a mostly unaltered phase transformation sequence compared to lower heating rates.

  3. Hydralazine-enhanced selective heating of transmissible venereal tumor implants in dogs.

    PubMed

    Voorhees, W D; Babbs, C F

    1982-10-01

    This study was designed to test the hypothesis that vasodilator drugs can enhance selective heating of solid tumors by producing a favorable redistribution of blood flow between tumor and normal tissues. Subcutaneous transmissible venereal tumor implants were heated by inductive diathermy using Helmholtz coils in 8 dogs. The temperature rise in tumor and adjacent muscle was measured before and after giving hydralazine (0.5 mg/kg i.v.). Blood flow to the tumors and underlying muscle was measured with radioactive tracer microspheres. Before hydralazine treatment mean muscle blood flow was about one-third tumor blood flow (0.11 +/- 0.02 vs 0.28 +/- 0.09 ml/min/g), and tumor and normal muscle temperatures were not significantly different (40.0 +/- 0.6 vs 39.7 +/- 0.1 degrees C). After hydralazine tumor blood flow decreased and muscle blood flow increased in every dog, and selective heating of the tumors became possible. Muscle blood flow averaged 0.67 +/- 0.13 ml/min/g, 17 times greater than tumor blood flow, which decreased to 0.04 +/- 0.02 ml/min/g. Core tumor temperature was 48.0 +/- 0.9 vs 38.5 +/- 0.5 degrees C for underlying muscle. Blood pressure was maintained at 80 +/- 5.7 mmHg. These results demonstrate that adjuvant treatment with vasodilators is a promising technique to increase the temperature difference between tumors and surrounding normal tissues during local heat therapy.

  4. Thermal preconditioning and heat-shock protein 72 preserve synaptic transmission during thermal stress.

    PubMed

    Kelty, Jonathan D; Noseworthy, Peter A; Feder, Martin E; Robertson, R Meldrum; Ramirez, Jan-Marino

    2002-01-01

    As with other tissues, exposing the mammalian CNS to nonlethal heat stress (i.e., thermal preconditioning) increases levels of heat-shock proteins (Hsps) such as Hsp70 and enhances the viability of neurons under subsequent stress. Using a medullary slice preparation from a neonatal mouse, including the site of the neural network that generates respiratory rhythm (the pre-Bötzinger complex), we show that thermal preconditioning has an additional fundamental effect, protection of synaptic function. Relative to 30 degrees C baseline, initial thermal stress (40 degrees C) greatly increased the frequency of synaptic currents recorded without pharmacological manipulation by approximately 17-fold (p < 0.01) and of miniature postsynaptic currents (mPSCs) elicited by GABA (20-fold) glutamate (10-fold), and glycine (36-fold). Thermal preconditioning (15 min at 40 degrees C) eliminated the increase in frequency of overall synaptic transmission during acute thermal stress and greatly attenuated the frequency increases of GABAergic, glutamatergic, and glycinergic mPSCs (for each, p < 0.05). Moreover, without thermal preconditioning, incubation of slices in solution containing inducible Hsp70 (Hsp72) mimicked the effect of thermal preconditioning on the stress-induced release of neurotransmitter. That preconditioning and exogenous Hsp72 can affect and preserve normal physiological function has important therapeutic implications.

  5. High-power microwave transmission and launching systems for fusion plasma heating systems

    SciTech Connect

    Bigelow, T.S.

    1989-01-01

    Microwave power in the 30- to 300-GHz frequency range is becoming widely used for heating of plasma in present-day fusion energy magnetic confinement experiments. Microwave power is effective in ionizing plasma and heating electrons through the electron cyclotron heating (ECH) process. Since the power is absorbed in regions of the magnetic field where resonance occurs and launching antennas with narrow beam widths are possible, power deposition location can be highly controlled. This is important for maximizing the power utilization efficiency and improving plasma parameters. Development of the gyrotron oscillator tube has advanced in recent years so that a 1-MW continuous-wave, 140-GHz power source will soon be available. Gyrotron output power is typically in a circular waveguide propagating a circular electric mode (such as TE/sub 0,2/) or a whispering-gallery mode (such as TE/sub 15,2/), depending on frequency and power level. An alternative high-power microwave source currently under development is the free-electron laser (FEL), which may be capable of generating 2-10 MW of average power at frequencies of up to 500 GHz. The FEL has a rectangular output waveguide carrying the TE/sub 0,1/ mode. Because of its higher complexity and cost, the high-average-power FEL is not yet as extensively developed as the gyrotron. In this paper, several types of operating ECH transmission systems are discussed, as well systems currently being developed. The trend in this area is toward higher power and frequency due to the improvements in plasma density and temperature possible. Every system requires a variety of components, such as mode converters, waveguide bends, launchers, and directional couplers. Some of these components are discussed here, along with ongoing work to improve their performance. 8 refs.

  6. Transmission

    SciTech Connect

    Sugano, K.

    1988-12-27

    A transmission is described which consists of: an input shaft; an output shaft; a first planetary gear set including a first sun gear selectively connectable by a first clutch to the input shaft, a first carrier selectively connectable by a second clutch to the input shaft and a first ring gear connected to the output shaft. The first sun gear selectively held stationary by a first brake, the first carrier is allowed to rotate in the same forward direction as the input shaft when the second clutch is engaged, but prevented from rotating in a reverse direction opposite to the forward direction by a first one-way clutch, the first carrier being selectively held stationary by a second brake; a second planetary gear set including a second sun gear connected to the input shaft, a second carrier connected to the first ring gear and also the the output shaft, and a second ring gear.

  7. Transmission electron microscopy study of Listeria monocytogenes serotype 1/2a cells exposed to sublethal heat stress and carvacrol

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to investigate the morphological changes that occurred in Listeria monocytogenes serotype 1/2a cells as visualized by transmission electron microscopy (TEM) after exposure to sublethal heat stress at 48°C for 60 min and in combination with lethal concentration of carv...

  8. Transmission line model for strained quantum well lasers including carrier transport and carrier heating effects.

    PubMed

    Xia, Mingjun; Ghafouri-Shiraz, H

    2016-03-01

    This paper reports a new model for strained quantum well lasers, which are based on the quantum well transmission line modeling method where effects of both carrier transport and carrier heating have been included. We have applied this new model and studied the effect of carrier transport on the output waveform of a strained quantum well laser both in time and frequency domains. It has been found that the carrier transport increases the turn-on, turn-off delay times and damping of the quantum well laser transient response. Also, analysis in the frequency domain indicates that the carrier transport causes the output spectrum of the quantum well laser in steady state to exhibit a redshift which has a narrower bandwidth and lower magnitude. The simulation results of turning-on transients obtained by the proposed model are compared with those obtained by the rate equation laser model. The new model has also been used to study the effects of pump current spikes on the laser output waveforms properties, and it was found that the presence of current spikes causes (i) wavelength blueshift, (ii) larger bandwidth, and (iii) reduces the magnitude and decreases the side-lobe suppression ratio of the laser output spectrum. Analysis in both frequency and time domains confirms that the new proposed model can accurately predict the temporal and spectral behaviors of strained quantum well lasers.

  9. Transmission electron microscopy assisted in-situ joule heat dissipation study of individual InAs nanowires

    SciTech Connect

    Xu, T. T.; Wei, X. L. E-mail: qingchen@pku.edu.cn; Shu, J. P.; Chen, Q. E-mail: qingchen@pku.edu.cn

    2013-11-04

    Managing heat transport at nanoscale is an important and challenging task for nanodevice applications and nanostructure engineering. Herein, through in-situ engineering nanowire (NW)-electrode contacts with electron beam induced carbon deposition in a transmission electron microscope, Joule heat dissipation along individual suspended Indium Arsenide NWs is well managed to obtain pre-designed temperature profiles along NWs. The temperature profiles are experimentally determined by the breakdown site of NWs under Joule heating and breakdown temperature measurement. A model with NW-electrode contacts being well considered is proposed to describe heat transport along a NW. By fitting temperature profiles with the model, thermal conductance at NW-electrode contacts is obtained. It is found that, the temperature profile along a specific NW is mainly governed by the relative thermal conductance at the two NW-electrode contacts, which is engineered in experiments.

  10. High-power microwave transmission systems for electron-cyclotron-resonance plasma heating

    SciTech Connect

    Vernon, R.J.

    1991-08-01

    This progress report is for the sixth year of a grant from the US Department of Energy for the design, development, and fabrication of ECRH transmission and mode conversion systems to transport microwave power from a gyrotron to a magnetically confined plasma. The design and low-power testing of new and improved components for such systems and development of underlying theory is the focus of this project. Devising and improving component testing and diagnostic techniques is also an important part of this effort. The development of possible designs for sections of gyrotrons themselves, such as tapers or Vlasov-type launchers, in support of the Varian gyrotron development program is also considered when appropriate. We also provide support to other groups working on ECR heating of magnetically confined plasmas such as the groups at General Atomics, the University of Texas at Austin, and Lawrence Livermore National Laboratory. During the last year, we designed and had fabricated a two-dimensional Vlasov antenna system for a 110 GHz TE{sub 15,2} mode gyrotron for possible use at General Atomics. The system included the launcher section, a visor, main reflector, and focusing reflector. Programs to generate the tool-path profiles to cut the General Atomics'' Vlasov components on a milling machine were developed. We have also developed state-of-the art theory and programs for three-dimensional whispering-gallery-mode Vlasov antenna systems. A design for a 110 GHz TE{sub 01}-TE{sub 15,2} mode converter system for cold testing WGM Vlasov antenna systems was developed and is currently being fabricated also.

  11. Experimental study on heat transmission to the vestibule during CO2 laser use in revision stapes surgery.

    PubMed

    Szymański, M; Morshed, K; Mills, R

    2007-01-01

    We studied the transmission of heat to the vestibule during revision stapes surgery with a piston in situ, using a CO2 laser, in an in vitro model. A type K thermocouple was placed around the medial end of stainless steel and fluoroplastic wire pistons in a 'vestibule' filled with saline. The effect of laser hits on fluoroplastic wire and stainless steel stapes prostheses was investigated. The effect of introducing a vein graft to seal the stapedotomy was also examined. Greater temperature rises occurred with stainless steel than with fluoroplastic wire pistons. The addition of the vein graft reduced heat transmission. Application of the CO2 laser to fluoroplastic wire pistons, using the power settings suggested by the manufacturer, is not likely to damage the inner-ear structures. Application of 6 W laser energy to stainless steel pistons can potentially disturb the inner-ear function.

  12. Transmission grating streaked spectrometer for the diagnosis of soft x-ray emission from ultrahigh intensity laser heated targets

    SciTech Connect

    Eagleton, R.T.; James, S.F.

    2004-10-01

    A free-standing gold transmission grating with a period of 5000 A has been coupled to a soft x-ray sensitive streak camera with a limiting temporal resolution of 10 ps. The streak camera is equipped with a caesium iodide transmission photocathode and observations have been made in the 10-100 A regime. For a small source (200 {mu}m diameter) the spectral resolution is predicted to be around 2.5 A. This has been confirmed by examination of the Lyman-{alpha} line in hydrogen-like laser heated boron. A recorded linewidth of 2.44 A is demonstrated. The instrument has been used to diagnose the soft x-ray emission from a plastic (CH) foil target heated by an ultra-intense (2x10{sup 20} W cm{sup -2}) laser pulse.

  13. Transmission grating streaked spectrometer for the diagnosis of soft x-ray emission from ultrahigh intensity laser heated targets

    NASA Astrophysics Data System (ADS)

    Eagleton, R. T.; James, S. F.

    2004-10-01

    A free-standing gold transmission grating with a period of 5000 Å has been coupled to a soft x-ray sensitive streak camera with a limiting temporal resolution of 10 ps. The streak camera is equipped with a caesium iodide transmission photocathode and observations have been made in the 10-100 Å regime. For a small source (200 μm diameter) the spectral resolution is predicted to be around 2.5 Å. This has been confirmed by examination of the Lyman-α line in hydrogen-like laser heated boron. A recorded linewidth of 2.44 Å is demonstrated. The instrument has been used to diagnose the soft x-ray emission from a plastic (CH) foil target heated by an ultra-intense (2×1020 W cm-2) laser pulse.

  14. Radiation Heat Measurement on Thermally-Isolated Double-Pipe for DC Superconducting Power Transmission

    NASA Astrophysics Data System (ADS)

    Hamabe, M.; Nasu, Y.; Ninomiya, A.; Ishiguro, Y.; Kusaka, S.; Yamaguchi, S.

    2008-03-01

    Multilayer insulator (MLI) is a strong tool for use as a radiation heat shield, though the use of MLI has disadvantages in construction and evacuation for a long superconducting power cable. We have proposed the "MLI-free" radiation heat shielding for DC superconducting power cable and have measured the radiation heat transfer for thermally-isolated double-pipes with different surfaces. Here, Zn coating, MLI, and Al-foil sheet were tested. Consequently, from the radiation heat of 9.7 W/m for bare stainless-steel pipe, Zn-coated stainless-steel surface reduced to 2.6 W/m, whereas the use of MLI reduced to 0.2 W/m. It is expected that the simultaneous use of Zn coating and MLI can reduce the number of total MLI sheets to reduce the evacuation time.

  15. The use of CO(2) laser in revision stapes surgery: experimental studies on heat transmission to the vestibule.

    PubMed

    Szymański, Marcin; Morshed, Kamal; Mills, Robert P

    2007-01-01

    The aim of the study was to assess the effect of CO(2) laser on stapes prostheses and measure the heat transmission to the vestibule in experiment model. CO(2) laser was applied on two types of prostheses with power settings (2 and 6W; 0.05 s). Transmission of heat to the 'vestibule' was measured using type K thermocouple and DC-80 data logger during application of the laser on prostheses using a training model of temporal bone. Application of the laser on stainless steel prosthesis did not have any effect on the structure of the prosthesis. The use of the laser on the fluoroplastic-wire piston caused melting and produced holes in the piston. Greater temperature rises occurred with stainless steel than with the fluoroplastic-wire piston. Application of CO(2) laser on stainless steel pistons with 6W can produce inner ear trauma. The use of the laser on fluoroplastic-wire piston is not likely to irritate the inner ear.

  16. Effects of VLF heating of ionosphere on the transmission cone of MF waves propagating from ground to space

    NASA Astrophysics Data System (ADS)

    Lefeuvre, F.; Pincon, J.; Parrot, M.

    2012-12-01

    Global maps of VLF-MF waves observed by the low-altitude (~700 km) DEMETER satellite (Parrot et al., 2009) have pointed out localized enhancements of wave energy above the most powerful VLF transmitters and their conjugate regions, both in the 18-25 kHz frequency range (VLF transmitters) and in the 2.-2.5 MHz frequency range (emissions associated with lightning discharges). Under hypothesis made for the computation of the refractive index by the Appleton-Hartree formula, simulations are conducted to estimate the effect of VLF heating on the transmission cone of MF waves propagating from ground to space. The method used consists in the computation of the vertical variations of the Real part of the refractive index n and of the α attenuation factor (α = ω. Imag(n)/c), with an IRI electron density profile derived from the geophysical parameters of a DEMETER orbit and an hybrid collision frequency model taking into account of theoretical and experimental data. Half-angles of the transmission cone are estimated: first, at the X=1 (X=fpe2/f2) low altitude boundary (where Ordinary mode waves may be converted into Extraordinary mode waves), and second, at the high-altitude X=1 boundary (where Extraordinary mode waves may be converted into Ordinary mode waves). It is shown that enhancements in the collision frequencies, produced by VLF heating at altitudes where the product of the collision frequency ν by the electronic density Ne is maximum (i.e. at altitudes including the low-altitude and the high-altitude X=1 boundaries), open the half angle of the transmission cones for MF waves which cross the ionosphere, and so explain enhancements of wave energy observed in the 2. - 2.5 MHz band above the powerful VLF transmitters and their conjugate regions.

  17. Hydraulic transmissivity and heat exchange efficiency of open fractures: a model based on lowpass filtered apertures

    NASA Astrophysics Data System (ADS)

    Neuville, Amélie; Toussaint, Renaud; Schmittbuhl, Jean

    2011-09-01

    Natural open joints in rocks commonly present multiscale self-affine apertures. This geometrical complexity affects fluid transport and heat exchange between the flowing fluid and the surrounding rock. In particular, long range correlations of self-affine apertures induce strong channelling of the flow which influences both mass and heat advection. A key question is to find a geometrical model of the complex aperture that describes at best the macroscopic properties (hydraulic conductivity, heat exchange) with the smallest number of parameters. Solving numerically the Stokes and heat equations with a lubrication approximation, we show that a low pass filtering of the aperture geometry provides efficient estimates of the effective hydraulic and thermal properties (apertures). A detailed study of the influence of the bandwidth of the lowpass filtering on these transport properties is also performed. For instance, keeping the information of amplitude only of the largest Fourier length scales allows us to reach already an accuracy of 9 per cent on the hydraulic and the thermal apertures.

  18. Investigating Metal-Enrichment, Tidal Heating, and Clouds in the Emission and Transmission Spectra of GJ 436b

    NASA Astrophysics Data System (ADS)

    Morley, Caroline; Knutson, Heather; Line, Michael R.; Fortney, Jonathan J.; Marley, Mark S.; Teal, Dillon; Lupu, Roxana E.

    2016-10-01

    One of the legacies of the Kepler mission is the preponderance of planets between Earth and Neptune in radius; a major goal of atmospheric studies is to characterize planets spanning this size range. What is the range of compositions of these objects, and does these compositions correlate with planet mass (or some other property)? Do they have clouds and/or hazes in their atmospheres? How do atmospheric dynamics shape our observations? The Neptune-mass GJ 436b is one of the most-studied transiting exoplanets to date, with repeated measurements of both its thermal emission and transmission spectra. I will discuss new observations of GJ 436b's thermal emission at 3.6 and 4.5 μm, which reduce the uncertainties in estimates of GJ 436b's flux at those wavelengths and demonstrate consistency between Spitzer observations spanning more than 7 years. For the first time, we analyze the Spitzer thermal emission photometry and Hubble WFC3 transmission spectrum in tandem. I will show how we use a powerful dual-pronged modeling approach, comparing these data to both self-consistent and retrieval models. We vary the metallicity, intrinsic luminosity from tidal heating, disequilibrium chemistry, and heat redistribution. We also study the potential effect of both clouds and photochemical hazes on the spectra, but do not find strong evidence for either. The self-consistent and retrieval modeling combine to suggest that GJ 436b has a high atmospheric metallicity, with best fits at or above several hundred times solar metallicity, tidal heating warming its interior with best-fit intrinsic effective effective temperatures around 300-350 K, and disequilibrium chemistry. We suggest that Neptune-mass planets may be a more diverse class than previously imagined, with a range of metal-enhancements spanning over an order of magnitude from 50-100 to perhaps over 1000× solar metallicity. High fidelity observations with instruments like JWST will be critical for characterizing this diversity.

  19. Focused Ion Beam Preparation of Specimens for Micro-Electro-Mechanical System-based Transmission Electron Microscopy Heating Experiments.

    PubMed

    Vijayan, Sriram; Jinschek, Joerg R; Kujawa, Stephan; Greiser, Jens; Aindow, Mark

    2017-08-01

    Micro-electro-mechanical systems (MEMS)-based heating holders offer exceptional control of temperature and heating/cooling rates for transmission electron microscopy experiments. The use of such devices is relatively straightforward for nano-particulate samples, but the preparation of specimens from bulk samples by focused ion beam (FIB) milling presents significant challenges. These include: poor mechanical integrity and site selectivity of the specimen, ion beam damage to the specimen and/or MEMS device during thinning, and difficulties in transferring the specimen onto the MEMS device. Here, we describe a novel FIB protocol for the preparation and transfer of specimens from bulk samples, which involves a specimen geometry that provides mechanical support to the electron-transparent region, while maximizing the area of that region and the contact area with the heater plate on the MEMS chip. The method utilizes an inclined stage block that minimizes exposure of the chip to the ion beam during milling. This block also allows for accurate and gentle placement of the FIB-cut specimen onto the chip by using simultaneous electron and ion beam imaging during transfer. Preliminary data from Si and Ag on Si samples are presented to demonstrate the quality of the specimens that can be obtained and their stability during in situ heating experiments.

  20. A MEMS-based heating holder for the direct imaging of simultaneous in-situ heating and biasing experiments in scanning/transmission electron microscopes.

    PubMed

    Mele, Luigi; Konings, Stan; Dona, Pleun; Evertz, Francis; Mitterbauer, Christoph; Faber, Pybe; Schampers, Ruud; Jinschek, Joerg R

    2016-04-01

    The introduction of scanning/transmission electron microscopes (S/TEM) with sub-Angstrom resolution as well as fast and sensitive detection solutions support direct observation of dynamic phenomena in-situ at the atomic scale. Thereby, in-situ specimen holders play a crucial role: accurate control of the applied in-situ stimulus on the nanostructure combined with the overall system stability to assure atomic resolution are paramount for a successful in-situ S/TEM experiment. For those reasons, MEMS-based TEM sample holders are becoming one of the preferred choices, also enabling a high precision in measurements of the in-situ parameter for more reproducible data. A newly developed MEMS-based microheater is presented in combination with the new NanoEx™-i/v TEM sample holder. The concept is built on a four-point probe temperature measurement approach allowing active, accurate local temperature control as well as calorimetry. In this paper, it is shown that it provides high temperature stability up to 1,300°C with a peak temperature of 1,500°C (also working accurately in gaseous environments), high temperature measurement accuracy (<4%) and uniform temperature distribution over the heated specimen area (<1%), enabling not only in-situ S/TEM imaging experiments, but also elemental mapping at elevated temperatures using energy-dispersive X-ray spectroscopy (EDS). Moreover, it has the unique capability to enable simultaneous heating and biasing experiments.

  1. Filters Reduce the Risk of Bacterial Transmission from Contaminated Heated Humidifiers Used with CPAP for Obstructive Sleep Apnea

    PubMed Central

    Ortolano, Girolamo A.; Schaffer, Jeffrey; McAlister, Morven B.; Stanchfield, Ilia; Hill, Elizabeth; Vandenburgh, Liliana; Lewis, Michelle; John, Shirnett; Canonica, Francis P.; Cervia, Joseph S.

    2007-01-01

    Rationale: The treatment of choice for obstructive sleep apnea (OSA) is nasal continuous positive airway pressure (nCPAP) during sleep, but dryness of the upper airway compromises compliance. Heated humidifiers may mitigate such noncompliance; however, recent observations suggest that their use, particularly if not cleaned, increases the risk of respiratory infections. Humidifier water may be contaminated, but the long-held view that passive humidifiers cannot aerosolize water may obscure the perception of risk of infection. Objectives: This study challenges the long-held view that “passover” humidifiers do not aerosolize water. With such evidence, this study characterizes the performance of filters to reduce the potential risk of contamination. Methods: Heated humidifier water contaminated with bacteria was studied under conditions simulating week-long use of nCPAP for OSA. Results: Bacteria were recovered in 9 of 11 tests from the breathing tubes of CPAP devices fitted with heated humidifiers with water contaminated with Brevundimonas diminuta or Serratia marcescens. Recoverable bacteria ranged from tens to thousands of colony forming units when tested at air flow rates of 60 liters per minute for 90 minutes. Neither organism was recovered from the circuit tubing when a hydrophobic breathing-circuit filter was positioned between the humidifier and face-mask tubing with a commercially available nCPAP machine tested under simulated-use conditions. Conclusion: Data suggest that patients with OSA being treated with nCPAP fitted with humidifiers may be aerosolizing bacteria, putting them at risk for developing respiratory infections and that the use of a hydrophobic filter may attenuate the passage of microbes from contaminated humidifier water. Citation: Ortolano GA; Schaffer J; McAlister MB et al. Filters reduce the risk of bacterial transmission from contaminated heated humidifiers used with CPAP for obstructive sleep apnea. J Clin Sleep Med 2007;3(7):700–705

  2. Transmission of heat to the vestibule during revision stapes surgery using a KTP laser: an in vitro study.

    PubMed

    Szymanski, Marcin; Mills, Robert; Abel, Eric

    2003-05-01

    The transmission of heat to the vestibule during revision stapes surgery with a piston in situ has been studied using a KTP laser in an in vitro model. A type K thermocouple was placed around the medial of each piston tested in a 'vestibule' filled with saline. The effect of laser hits on fluoroplastic, fluoroplastic-wire and stainless steel stapes prostheses was investigated. The effect of adding blood to the operative field, of introducing a vein graft to seal the stapedotomy and of vaporizing soft tissue in the oval window were also examined. Greater temperature rises occurred with stainless steel than with the other piston types and smaller rises occurred when there was a vein graft in situ. The maximum temperature rise recorded was 2.6 degrees C. We conclude that the use of the KTP laser to clear soft tissue from the oval window is safe when operated at the power levels recommended by the manufacturer.

  3. Effect of heating on the stability of amyloid A (AA) fibrils and the intra- and cross-species transmission of AA amyloidosis.

    PubMed

    Ogawa, Saki; Murakami, Tomoaki; Inoshima, Yasuo; Ishiguro, Naotaka

    2015-01-01

    Amyloid A (AA) amyloidosis is a protein misfolding disease characterized by extracellular deposition of AA fibrils. AA fibrils are found in several tissues from food animals with AA amyloidosis. For hygienic purposes, heating is widely used to inactivate microbes in food, but it is uncertain whether heating is sufficient to inactivate AA fibrils and prevent intra- or cross-species transmission. We examined the effect of heating (at 60 °C or 100 °C) and autoclaving (at 121 °C or 135 °C) on murine and bovine AA fibrils using Western blot analysis, transmission electron microscopy (TEM), and mouse model transmission experiments. TEM revealed that a mixture of AA fibrils and amorphous aggregates appeared after heating at 100 °C, whereas autoclaving at 135 °C produced large amorphous aggregates. AA fibrils retained antigen specificity in Western blot analysis when heated at 100 °C or autoclaved at 121 °C, but not when autoclaved at 135 °C. Transmissible pathogenicity of murine and bovine AA fibrils subjected to heating (at 60 °C or 100 °C) was significantly stimulated and resulted in amyloid deposition in mice. Autoclaving of murine AA fibrils at 121 °C or 135 °C significantly decreased amyloid deposition. Moreover, amyloid deposition in mice injected with murine AA fibrils was more severe than that in mice injected with bovine AA fibrils. Bovine AA fibrils autoclaved at 121 °C or 135 °C did not induce amyloid deposition in mice. These results suggest that AA fibrils are relatively heat stable and that similar to prions, autoclaving at 135 °C is required to destroy the pathogenicity of AA fibrils. These findings may contribute to the prevention of AA fibril transmission through food materials to different animals and especially to humans.

  4. Combining nanocalorimetry and dynamic transmission electron microscopy for in situ characterization of materials processes under rapid heating and cooling

    SciTech Connect

    Grapes, Michael D.; LaGrange, Thomas; Reed, Bryan W.; Campbell, Geoffrey H.; Friedman, Lawrence H.; LaVan, David A.; Weihs, Timothy P.

    2014-08-15

    Nanocalorimetry is a chip-based thermal analysis technique capable of analyzing endothermic and exothermic reactions at very high heating and cooling rates. Here, we couple a nanocalorimeter with an extremely fast in situ microstructural characterization tool to identify the physical origin of rapid enthalpic signals. More specifically, we describe the development of a system to enable in situ nanocalorimetry experiments in the dynamic transmission electron microscope (DTEM), a time-resolved TEM capable of generating images and electron diffraction patterns with exposure times of 30 ns–500 ns. The full experimental system consists of a modified nanocalorimeter sensor, a custom-built in situ nanocalorimetry holder, a data acquisition system, and the DTEM itself, and is capable of thermodynamic and microstructural characterization of reactions over a range of heating rates (10{sup 2} K/s–10{sup 5} K/s) accessible by conventional (DC) nanocalorimetry. To establish its ability to capture synchronized calorimetric and microstructural data during rapid transformations, this work describes measurements on the melting of an aluminum thin film. We were able to identify the phase transformation in both the nanocalorimetry traces and in electron diffraction patterns taken by the DTEM. Potential applications for the newly developed system are described and future system improvements are discussed.

  5. Combining nanocalorimetry and dynamic transmission electron microscopy for in situ characterization of materials processes under rapid heating and cooling.

    PubMed

    Grapes, Michael D; LaGrange, Thomas; Friedman, Lawrence H; Reed, Bryan W; Campbell, Geoffrey H; Weihs, Timothy P; LaVan, David A

    2014-08-01

    Nanocalorimetry is a chip-based thermal analysis technique capable of analyzing endothermic and exothermic reactions at very high heating and cooling rates. Here, we couple a nanocalorimeter with an extremely fast in situ microstructural characterization tool to identify the physical origin of rapid enthalpic signals. More specifically, we describe the development of a system to enable in situ nanocalorimetry experiments in the dynamic transmission electron microscope (DTEM), a time-resolved TEM capable of generating images and electron diffraction patterns with exposure times of 30 ns-500 ns. The full experimental system consists of a modified nanocalorimeter sensor, a custom-built in situ nanocalorimetry holder, a data acquisition system, and the DTEM itself, and is capable of thermodynamic and microstructural characterization of reactions over a range of heating rates (10(2) K/s-10(5) K/s) accessible by conventional (DC) nanocalorimetry. To establish its ability to capture synchronized calorimetric and microstructural data during rapid transformations, this work describes measurements on the melting of an aluminum thin film. We were able to identify the phase transformation in both the nanocalorimetry traces and in electron diffraction patterns taken by the DTEM. Potential applications for the newly developed system are described and future system improvements are discussed.

  6. Convective Heat Transfer Coefficients of Automatic Transmission Fluid Jets with Implications for Electric Machine Thermal Management: Preprint

    SciTech Connect

    Bennion, Kevin; Moreno, Gilberto

    2015-09-29

    Thermal management for electric machines (motors/ generators) is important as the automotive industry continues to transition to more electrically dominant vehicle propulsion systems. Cooling of the electric machine(s) in some electric vehicle traction drive applications is accomplished by impinging automatic transmission fluid (ATF) jets onto the machine's copper windings. In this study, we provide the results of experiments characterizing the thermal performance of ATF jets on surfaces representative of windings, using Ford's Mercon LV ATF. Experiments were carried out at various ATF temperatures and jet velocities to quantify the influence of these parameters on heat transfer coefficients. Fluid temperatures were varied from 50 degrees C to 90 degrees C to encompass potential operating temperatures within an automotive transaxle environment. The jet nozzle velocities were varied from 0.5 to 10 m/s. The experimental ATF heat transfer coefficient results provided in this report are a useful resource for understanding factors that influence the performance of ATF-based cooling systems for electric machines.

  7. a High-Power Microwave Transmission and Launching System for Plasma Heating on the Ornl ATF Experiment.

    NASA Astrophysics Data System (ADS)

    Bigelow, Timothy Stuart

    1990-01-01

    A high power microwave transmission and launching system has been developed for Electron Cyclotron Heating (ECH) of plasmas in the Advanced Toroidal Facility (ATF) fusion confinement experiment at Oak Ridge National Laboratory. Microwave power is generated by two 53 GHz, 200 KW cw gyrotron tubes. A waveguide transmission and launching system for each tube has been designed and built with the goal of depositing the maximum amount of power at the center of the plasma. Centralized deposition of the microwave power is possible at high frequencies by use of a launcher with a narrow radiated beamwidth and carefully controlled polarization to couple to electrons at the cyclotron resonant surface. In order for the transmission systems to operate at this high frequency and power level, highly over-moded waveguides have been used to reduce losses and arcing. To produce a narrow, polarized beam, the waveguide system was designed for minimum parasitic mode conversion so that the launcher can operate with nearly a single input mode. Several waveguide components were developed for the waveguide system including: a waveguide mode analyzing directional coupler, a rippled-wall mode converter, improved miter bends, and vacuum pumpout sections. To determine the mode purity of these components and efficiency of the system, laboratory measurement techniques for over-moded waveguide component evaluation were developed. A polarization controlled beam launcher was developed which launches a ~ 12 cm (-20 dB) beamwidth linearly polarized beam. The plane of polarization can be rotated to allow optimum coupling to either extra-ordinary or ordinary plasma waves. The transmission and launching system performed reliably. Modeling of electromagnetic wave propagation in the ATF plasma and measurement of beam absorption and plasma parameters were performed to determine the overall effectiveness of the ECH system. A coupled-mode wave propagation code was written to investigate the effect of magnetic

  8. Far-field optical degradation due to near-field transmission through a turbulent heated jet.

    PubMed

    Cicchiello, J M; Jumper, E J

    1997-09-01

    When a laser beam traverses an optically active, turbulent flow field, the laser wave front is aberrated by the flow. Density variations in a heated two-dimensional jet, for example, correspond to index-of-refraction variations, and this modulation of the index in the fluid can imprint an optical phase disturbance, or phase error, onto the laser wave front. Adaptive-optic systems seek to correct the phase error of the wave front, and thus restore the integrity of the far-field irradiance pattern. Given a near-field spatial mapping of a phase disturbance, the far-field irradiance pattern of the affected wave front can be calculated with Fourier-optics techniques. A Fourier-optics computer code was used to study the far-field irradiance patterns arising from actual time-varying measurements of a fluid-induced phase error. The time-averaged Strehl ratio was studied to provide insight into the spatial and temporal design requirements for adaptive-optic systems applied to the time series of near-field spatial phase-error maps.

  9. Manufacture, solar transmission, and heat transfer characteristics of large-celled honeycomb transparent insulation

    SciTech Connect

    Hollands, K.G.T. ); Iynkaran, K. ); Ford, C. ); Platzer, W.J. )

    1992-11-01

    A method for manufacturing thin-walled (about 20 {mu}m wall thickness), large-celled (about 10 mm hydraulic diameter of cell) honeycomb from FEP plastic is described. The honeycomb manufacturing method uses heat-sealing to join adjacent strips of plastic along thin lines. The honeycomb is sized to be just small enough to suppress convection, but in itself it provides little radiant suppression, so it is intended to be used in conjunction with low emissivity surfaces at one or both of its bounding faces to provide the necessary radiant reduction. In addition to the method for manufacture, measurements of the honeycomb's thermal conductance and solar transmittance are also reported. Mounted adjacent to a face with a thermal emittance of 0.1, a 40 mm deep honeycomb achieved thermal conductance values ranging from 1.4 to 2.4 W/m{sup 2} K when the temperature difference ranged from 10 to 80 K and the mean temperature from 290 to 360 K. At an angle of incidence of 45{degree}, the honeycomb achieved a solar transmittance of 92%.

  10. Investigation of Parallel Radiofrequency Transmission for the Reduction of Heating in Long Conductive Leads in 3 Tesla Magnetic Resonance Imaging

    PubMed Central

    McElcheran, Clare E.; Yang, Benson; Anderson, Kevan J. T.; Golenstani-Rad, Laleh; Graham, Simon J.

    2015-01-01

    Deep Brain Stimulation (DBS) is increasingly used to treat a variety of brain diseases by sending electrical impulses to deep brain nuclei through long, electrically conductive leads. Magnetic resonance imaging (MRI) of patients pre- and post-implantation is desirable to target and position the implant, to evaluate possible side-effects and to examine DBS patients who have other health conditions. Although MRI is the preferred modality for pre-operative planning, MRI post-implantation is limited due to the risk of high local power deposition, and therefore tissue heating, at the tip of the lead. The localized power deposition arises from currents induced in the leads caused by coupling with the radiofrequency (RF) transmission field during imaging. In the present work, parallel RF transmission (pTx) is used to tailor the RF electric field to suppress coupling effects. Electromagnetic simulations were performed for three pTx coil configurations with 2, 4, and 8-elements, respectively. Optimal input voltages to minimize coupling, while maintaining RF magnetic field homogeneity, were determined for all configurations using a Nelder-Mead optimization algorithm. Resulting electric and magnetic fields were compared to that of a 16-rung birdcage coil. Experimental validation was performed with a custom-built 4-element pTx coil. In simulation, 95-99% reduction of the electric field at the tip of the lead was observed between the various pTx coil configurations and the birdcage coil. Maximal reduction in E-field was obtained with the 8-element pTx coil. Magnetic field homogeneity was comparable to the birdcage coil for the 4- and 8-element pTx configurations. In experiment, a temperature increase of 2±0.15°C was observed at the tip of the wire using the birdcage coil, whereas negligible increase (0.2±0.15°C) was observed with the optimized pTx system. Although further research is required, these initial results suggest that the concept of optimizing pTx to reduce DBS

  11. Propagation of Torsional Alfvén Waves from the Photosphere to the Corona: Reflection, Transmission, and Heating in Expanding Flux Tubes

    NASA Astrophysics Data System (ADS)

    Soler, Roberto; Terradas, Jaume; Oliver, Ramón; Ballester, José Luis

    2017-05-01

    It has been proposed that Alfvén waves play an important role in the energy propagation through the solar atmospheric plasma and its heating. Here we theoretically investigate the propagation of torsional Alfvén waves in magnetic flux tubes expanding from the photosphere up to the low corona and explore the reflection, transmission, and dissipation of wave energy. We use a realistic variation of the plasma properties and the magnetic field strength with height. Dissipation by ion-neutral collisions in the chromosphere is included using a multifluid partially ionized plasma model. Considering the stationary state, we assume that the waves are driven below the photosphere and propagate to the corona, while they are partially reflected and damped in the chromosphere and transition region. The results reveal the existence of three different propagation regimes depending on the wave frequency: low frequencies are reflected back to the photosphere, intermediate frequencies are transmitted to the corona, and high frequencies are completely damped in the chromosphere. The frequency of maximum transmissivity depends on the magnetic field expansion rate and the atmospheric model, but is typically in the range of 0.04-0.3 Hz. Magnetic field expansion favors the transmission of waves to the corona and lowers the reflectivity of the chromosphere and transition region compared to the case with a straight field. As a consequence, the chromospheric heating due to ion-neutral dissipation systematically decreases when the expansion rate of the magnetic flux tube increases.

  12. Current conflicts in U.S. Electric transmission planning, cost allocation and renewable energy policies: More heat than light?

    SciTech Connect

    Bloom, David; Forrester, J. Paul; Klugman, Nadav

    2010-12-15

    To surmount obstacles to expanding and upgrading the nation's transmission system that are impeding development of the renewables sector, it is critical that these issues be resolved quickly and on a consistent rather than ad hoc basis. (author)

  13. Forward and Inverse Modeling of the Emission and Transmission Spectrum of GJ 436b: Investigating Metal Enrichment, Tidal Heating, and Clouds

    NASA Astrophysics Data System (ADS)

    Morley, Caroline V.; Knutson, Heather; Line, Michael; Fortney, Jonathan J.; Thorngren, Daniel; Marley, Mark S.; Teal, Dillon; Lupu, Roxana

    2017-02-01

    The Neptune-mass GJ 436b is one of the most studied transiting exoplanets with repeated measurements of its thermal emission and transmission spectra. We build on previous studies to answer outstanding questions about this planet, including its potentially high metallicity and tidal heating of its interior. We present new observations of GJ 436b’s thermal emission at 3.6 and 4.5 μm, which reduce uncertainties in estimates of GJ 436b’s flux at those wavelengths and demonstrate consistency between Spitzer observations spanning more than 7 yr. We analyze the Spitzer thermal emission photometry and Hubble WFC3 transmission spectrum. We use a dual-pronged modeling approach of both self-consistent and retrieval models. We vary the metallicity, intrinsic luminosity from tidal heating, disequilibrium chemistry, and heat redistribution. We also study clouds and photochemical hazes, but do not find strong evidence for either. The self-consistent and retrieval models combine to suggest that GJ 436b has a high atmospheric metallicity, with best fits at or above several hundred times solar metallicity, tidal heating warming its interior with best-fit intrinsic effective temperatures around 300–350 K, and disequilibrium chemistry. High metal enrichments (>600× solar) occur from the accretion of rocky, rather than icy, material. Assuming the interior temperature Tint ∼ 300–350 K, we find a dissipation factor Q‧ ∼ 2 × 105–106, larger than Neptune’s Q‧, implying a long tidal circularization timescale for the orbit. We suggest that Neptune-mass planets may be more diverse than imagined, with metal enhancements spanning several orders of magnitude, to perhaps over 1000× solar metallicity. High-fidelity observations with instruments like the James Webb Space Telescope will be critical for characterizing this diversity.

  14. In situ heating transmission electron microscopy observation of nanoeutectic lamellar structure in Sn-Ag-Cu alloy on Au under-bump metallization.

    PubMed

    Seo, Jong-Hyun; Yoon, Sang-Won; Kim, Kyou-Hyun; Chang, Hye-Jung; Lee, Kon-Bae; Seong, Tae-Yeon; Fleury, Eric; Ahn, Jae-Pyoung

    2013-08-01

    We investigated the microstructural evolution of Sn(96.4)Ag(2.8)Cu(0.8) solder through in situ heating transmission electron microscopy observations. As-soldered bump consisted of seven layers, containing the nanoeutectic lamella structure of AuSn and Au₅Sn phases, and the polygonal grains of AuSn₂ and AuSn₄, on Au-plated Cu bond pads. Here, we found that there are two nanoeutectic lamellar layers with lamella spacing of 40 and 250 nm. By in situ heating above 140°C, the nanoeutectic lamella of AuSn and Au₅Sn was decomposed with structural degradation by sphering and coarsening processes of the lamellar interface. At the third layer neighboring to the lamella layer, on the other hand, Au₅Sn particles with a zig-zag shape in AuSn matrix became spherical and were finally dissipated in order to minimize the interface energy between two phases. In the other layers except both lamella layers, polycrystal grains of AuSn₂ and AuSn₄ grew by normal grain growth during in situ heating. The high interface energy of nanoeutectic lamella and polygonal nanograins, which are formed by rapid solidification, acted as a principal driving force on the microstructural change during the in situ heating.

  15. Enhanced geothermal systems (EGS) with CO2 as heat transmission fluid--A scheme for combining recovery of renewable energy with geologic storage of CO2

    SciTech Connect

    Pruess, K.; Spycher, N.

    2009-05-01

    It has been suggested that enhanced geothermal systems (EGS) may be operated with supercritical CO{sub 2} instead of water as heat transmission fluid (D.W. Brown, 2000). Such a scheme could combine recovery of geothermal energy with simultaneous geologic storage of CO{sub 2}, a greenhouse gas. At geothermal temperature and pressure conditions of interest, the flow and heat transfer behavior of CO{sub 2} would be considerably different from water, and chemical interactions between CO{sub 2} and reservoir rocks would also be quite different from aqueous fluids. This paper summarizes our research to date into fluid flow and heat transfer aspects of operating EGS with CO{sub 2}. (Chemical aspects of EGS with CO{sub 2} are discussed in a companion paper; Xu and Pruess, 2010.) Our modeling studies indicate that CO{sub 2} would achieve heat extraction at larger rates than aqueous fluids. The development of an EGS-CO{sub 2} reservoir would require replacement of the pore water by CO{sub 2} through persistent injection. We find that in a fractured reservoir, CO{sub 2} breakthrough at production wells would occur rapidly, within a few weeks of starting CO{sub 2} injection. Subsequently a two-phase water-CO{sub 2} mixture would be produced for a few years,followed by production of a single phase of supercritical CO{sub 2}. Even after single-phase production conditions are reached,significant dissolved water concentrations will persist in the CO{sub 2} stream for many years. The presence of dissolved water in the production stream has negligible impact on mass flow and heat transfer rates.

  16. Transmission eigenvalues

    NASA Astrophysics Data System (ADS)

    Cakoni, Fioralba; Haddar, Houssem

    2013-10-01

    iterative least square method to identify the spherically stratified index of refraction from transmission eigenvalues. On the characterization of transmission eigenvalues in terms of far-field measurements, a promising new result is obtained by Kirsch and Lechleiter [21] showing how one can identify the transmission eigenvalues using the eigenvalues of the scattering operator which are available in terms of measured scattering data. In the paper by Kleefeld [22], an accurate method for computing transmission eigenvalues based on a surface integral formulation of the interior transmission problem and numerical methods for nonlinear eigenvalue problems is proposed and numerically validated for the scalar problem in three dimensions. On the other hand, the paper by Sun and Xu [23] investigates the computation of transmission eigenvalues for Maxwell's equations using a standard iterative method associated with a variational formulation of the interior transmission problem with an emphasis on the effect of anisotropy on transmission eigenvalues. From the perspective of using transmission eigenvalues in non-destructive testing, the paper by Cakoni and Moskow [24] investigates the asymptotic behavior of transmission eigenvalues with respect to small inhomogeneities. The paper by Nakamura and Wang [25] investigates the linear sampling method for the time dependent heat equation and analyses the interior transmission problem associated with this equation. Finally, in the paper by Finch and Hickmann [26], the spectrum of the interior transmission problem is related to the unique determination of the acoustic properties of a body in thermoacoustic imaging. We hope that this collection of papers will stimulate further research in the rapidly growing area of transmission eigenvalues and inverse scattering theory.

  17. Numerical analysis of the transmission efficiency of heat-drawn and chemically etched scanning near-field optical microscopes.

    PubMed

    Moar, P; Ladouceur, F; Cahill, L

    2000-04-20

    The scanning near-field optical microscope (SNOM) has been tested experimentally for a wide variety of applications, but, to date, there has been little work done on the numerical or analytical modeling of the optical field as it propagates throughout the SNOM probe. Therefore, the fabrication on the probes relies more on trial and error than on clear design principles. An algorithm has been developed for the study and optimization of the geometry of SNOM probes fabricated by the heat-drawn and the one-step chemically etched methods. The algorithm uses the finite-difference beam propagation method (FD-BPM) to model the field evolution throughout the SNOM structure.

  18. Heat-precipitation allows the efficient purification of a functional plant-derived malaria transmission-blocking vaccine candidate fusion protein.

    PubMed

    Beiss, Veronique; Spiegel, Holger; Boes, Alexander; Kapelski, Stephanie; Scheuermayer, Matthias; Edgue, Gueven; Sack, Markus; Fendel, Rolf; Reimann, Andreas; Schillberg, Stefan; Pradel, Gabriele; Fischer, Rainer

    2015-07-01

    Malaria is a vector-borne disease affecting more than two million people and accounting for more than 600,000 deaths each year, especially in developing countries. The most serious form of malaria is caused by Plasmodium falciparum. The complex life cycle of this parasite, involving pre-erythrocytic, asexual and sexual stages, makes vaccine development cumbersome but also offers a broad spectrum of vaccine candidates targeting exactly those stages. Vaccines targeting the sexual stage of P. falciparum are called transmission-blocking vaccines (TBVs). They do not confer protection for the vaccinated individual but aim to reduce or prevent the transmission of the parasite within a population and are therefore regarded as an essential tool in the fight against the disease. Malaria predominantly affects large populations in developing countries, so TBVs need to be produced in large quantities at low cost. Combining the advantages of eukaryotic expression with a virtually unlimited upscaling potential and a good product safety profile, plant-based expression systems represent a suitable alternative for the production of TBVs. We report here the high level (300 μg/g fresh leaf weight (FLW)) transient expression in Nicotiana benthamiana leaves of an effective TBV candidate based on a fusion protein F0 comprising Pfs25 and the C0-domain of Pfs230, and the implementation of a simple and cost-effective heat treatment step for purification that yields intact recombinant protein at >90% purity with a recovery rate of >70%. The immunization of mice clearly showed that antibodies raised against plant-derived F0 completely blocked the formation of oocysts in a malaria transmission-blocking assay (TBA) making F0 an interesting TBV candidate or a component of a multi-stage malaria vaccine cocktail.

  19. Novel device to conduct flash-heat treatment in efforts to reduce mother-to-child HIV transmission in low-resource areas.

    PubMed

    Suresh, Aneesha; Harn, Cassandra; Pollack, Erica; Kroon, Max; Poluta, Mladen; Kelso, David; Glucksberg, Matthew

    2012-01-01

    The objective of this design project was to create a device to prevent mother-to-child transmission (MTCT) of HIV through breast milk in preterm infants. Our team created a robust and intuitive device which utilizes Flash Heat Treatment (FHT), an established method to inactivate HIV. The FHT method heats jarred breast milk in boiling water for a short amount of time, enough to denature HIV reverse transcriptase while preserving the nutritional value of breast milk. Thorough observation of users and available resources in Cape Town, South Africa enabled establishment of a design that can be used in urban/peri-urban areas. User research conveyed that low cost and effortless household adaptability were the most important elements of the design. As a result, a modified electric kettle was designed to function as a breast milk pasteurization device. Published data illustrating temperature curves during FHT with corresponding virology tests on the pasteurized milk were used to verify whether the device is likely to function effectively. Experimental results indicate that the device matches the required temperature profile. After virology experimentation is complete, the new device may be incorporated into hospitals as well as households in the Cape Town area, and may be expanded to other low resource periurban/urban areas as well.

  20. Quantitative transmission electron microscopy analysis of multi-variant grains in present L1{sub 0}-FePt based heat assisted magnetic recording media

    SciTech Connect

    Ho, Hoan; Zhu, Jingxi; Kulovits, Andreas; Laughlin, David E.; Zhu, Jian-Gang

    2014-11-21

    We present a study on atomic ordering within individual grains in granular L1{sub 0}-FePt thin films using transmission electron microscopy techniques. The film, used as a medium for heat assisted magnetic recording, consists of a single layer of FePt grains separated by non-magnetic grain boundaries and is grown on an MgO underlayer. Using convergent-beam techniques, diffraction patterns of individual grains are obtained for a large number of crystallites. The study found that although the majority of grains are ordered in the perpendicular direction, more than 15% of them are multi-variant, or of in-plane c-axis orientation, or disordered fcc. It was also found that these multi-variant and in-plane grains have always grown across MgO grain boundaries separating two or more MgO grains of the underlayer. The in-plane ordered portion within a multi-variant L1{sub 0}-FePt grain always lacks atomic coherence with the MgO directly underneath it, whereas, the perpendicularly ordered portion is always coherent with the underlying MgO grain. Since the existence of multi-variant and in-plane ordered grains are severely detrimental to high density data storage capability, the understanding of their formation mechanism obtained here should make a significant impact on the future development of hard disk drive technology.

  1. Energy filtering transmission electron microscopy immunocytochemistry and antigen retrieval of surface layer proteins from Tannerella forsythensis using microwave or autoclave heating with citraconic anhydride

    PubMed Central

    2012-01-01

    Tannerella forsythensis (Bacteroides forsythus), an anaerobic Gram-negative species of bacteria that plays a role in the progression of periodontal disease, has a unique bacterial protein profile. It is characterized by two unique protein bands with molecular weights of more than 200 kDa. It also is known to have a typical surface layer (S-layer) consisting of regularly arrayed subunits outside the outer membrane. We examined the relationship between high molecular weight proteins and the S-layer using electron microscopic immunolabeling with chemical fixation and an antigen retrieval procedure consisting of heating in a microwave oven or autoclave with citraconic anhydride. Immunogold particles were localized clearly at the outermost cell surface. We also used energy-filtering transmission electron microscopy (EFTEM) to visualize 3, 3′-diaminobenzidine tetrahydrochloride (DAB) reaction products after microwave antigen retrieval with 1% citraconic anhydride. The three-window method for electron spectroscopic images (ESI) of nitrogen by the EFTEM reflected the presence of moieties demonstrated by the DAB reaction with horseradish peroxidase (HRP)-conjugated secondary antibodies instead of immunogold particles. The mapping patterns of net nitrogen were restricted to the outermost cell surface. PMID:22984898

  2. Energy filtering transmission electron microscopy immunocytochemistry and antigen retrieval of surface layer proteins from Tannerella forsythensis using microwave or autoclave heating with citraconic anhydride.

    PubMed

    Moriguchi, K; Mitamura, Y; Iwami, J; Hasegawa, Y; Higuchi, N; Murakami, Y; Maeda, H; Yoshimura, F; Nakamura, H; Ohno, N

    2012-11-01

    Tannerella forsythensis (Bacteroides forsythus), an anaerobic Gram-negative species of bacteria that plays a role in the progression of periodontal disease, has a unique bacterial protein profile. It is characterized by two unique protein bands with molecular weights of more than 200 kDa. It also is known to have a typical surface layer (S-layer) consisting of regularly arrayed subunits outside the outer membrane. We examined the relationship between high molecular weight proteins and the S-layer using electron microscopic immunolabeling with chemical fixation and an antigen retrieval procedure consisting of heating in a microwave oven or autoclave with citraconic anhydride. Immunogold particles were localized clearly at the outermost cell surface. We also used energy-filtering transmission electron microscopy (EFTEM) to visualize 3, 3'-diaminobenzidine tetrahydrochloride (DAB) reaction products after microwave antigen retrieval with 1% citraconic anhydride. The three-window method for electron spectroscopic images (ESI) of nitrogen by the EFTEM reflected the presence of moieties demonstrated by the DAB reaction with horseradish peroxidase (HRP)-conjugated secondary antibodies instead of immunogold particles. The mapping patterns of net nitrogen were restricted to the outermost cell surface.

  3. Abnormal cubic-tetragonal phase transition of barium strontium titanate nanoparticles studied by in situ Raman spectroscopy and transmission electron microscopy heating experiments

    SciTech Connect

    Zhang, Yin; Chen, Chen; Gao, Ran; Xia, Feng; Li, YueSheng; Che, Renchao

    2015-11-02

    Phase stability of the ferroelectric materials at high temperature is extremely important to their device performance. Ba{sub x}Sr{sub 1−x}TiO{sub 3} (BST) nanoparticles with different Sr contents (x = 1, 0.91, 0.65, 0.4, and 0) are prepared by a facile hydrothermal method. Using Raman spectroscopy and transmission electron microscopy (TEM) analyses under in situ heating conditions (up to 300 °C), the phase transitions of BST nanoparticles between 25 °C and 280 °C are comprehensively investigated. The original Curie temperature of BST nanoparticles decreases abruptly with the increase in Sr content, which is more obvious than in the bulk or film material. Besides, an abnormal phase transition from cubic to tetragonal structure is observed from BST nanoparticles and the transition temperature rises along with the increase in Sr content. Direct TEM evidences including a slight lattice distortion have been provided. Differently, BaTiO{sub 3} nanoparticles remained in the tetragonal phase during the above temperature ranges.

  4. Quantitative transmission electron microscopy analysis of multi-variant grains in present L10-FePt based heat assisted magnetic recording media

    NASA Astrophysics Data System (ADS)

    Ho, Hoan; Zhu, Jingxi; Kulovits, Andreas; Laughlin, David E.; Zhu, Jian-Gang

    2014-11-01

    We present a study on atomic ordering within individual grains in granular L10-FePt thin films using transmission electron microscopy techniques. The film, used as a medium for heat assisted magnetic recording, consists of a single layer of FePt grains separated by non-magnetic grain boundaries and is grown on an MgO underlayer. Using convergent-beam techniques, diffraction patterns of individual grains are obtained for a large number of crystallites. The study found that although the majority of grains are ordered in the perpendicular direction, more than 15% of them are multi-variant, or of in-plane c-axis orientation, or disordered fcc. It was also found that these multi-variant and in-plane grains have always grown across MgO grain boundaries separating two or more MgO grains of the underlayer. The in-plane ordered portion within a multi-variant L10-FePt grain always lacks atomic coherence with the MgO directly underneath it, whereas, the perpendicularly ordered portion is always coherent with the underlying MgO grain. Since the existence of multi-variant and in-plane ordered grains are severely detrimental to high density data storage capability, the understanding of their formation mechanism obtained here should make a significant impact on the future development of hard disk drive technology.

  5. Automated manual transmission controller

    DOEpatents

    Lawrie, Robert E.; Reed, Jr., Richard G.; Bernier, David R.

    1999-12-28

    A powertrain system for a hybrid vehicle. The hybrid vehicle includes a heat engine, such as a diesel engine, and an electric machine, which operates as both an electric motor and an alternator, to power the vehicle. The hybrid vehicle also includes a manual-style transmission configured to operate as an automatic transmission from the perspective of the driver. The engine and the electric machine drive an input shaft which in turn drives an output shaft of the transmission. In addition to driving the transmission, the electric machine regulates the speed of the input shaft in order to synchronize the input shaft during either an upshift or downshift of the transmission by either decreasing or increasing the speed of the input shaft. When decreasing the speed of the input shaft, the electric motor functions as an alternator to produce electrical energy which may be stored by a storage device. Operation of the transmission is controlled by a transmission controller which receives input signals and generates output signals to control shift and clutch motors to effect smooth launch, upshift shifts, and downshifts of the transmission, so that the transmission functions substantially as an automatic transmission from the perspective of the driver, while internally substantially functioning as a manual transmission.

  6. Multistage Planetary Power Transmissions

    NASA Technical Reports Server (NTRS)

    Hadden, G. B.; Dyba, G. J.; Ragen, M. A.; Kleckner, R. J.; Sheynin, L.

    1986-01-01

    PLANETSYS simulates thermomechanical performance of multistage planetary performance of multistage planetary power transmission. Two versions of code developed, SKF version and NASA version. Major function of program: compute performance characteristics of planet bearing for any of six kinematic inversions. PLANETSYS solves heat-balance equations for either steadystate or transient thermal conditions, and produces temperature maps for mechanical system.

  7. A laboratory study examining the impact of linen use on low-air-loss support surface heat and water vapor transmission rates.

    PubMed

    Williamson, Rachel; Lachenbruch, Charlie; VanGilder, Catherine

    2013-08-01

    Layers of linens are frequently placed under patients to manage moisture and/or assist with positioning immobile patients, including persons placed on a therapeutic surface because they are at risk for developing pressure ulcers. Because skin microclimate is believed to affect pressure ulcer risk, some therapeutic surfaces are designed to manage skin temperature and humidity (microclimate management). The purpose of this study was to measure the effects of linens and underpads on a low-air-loss (LAL) surface's ability to disperse heat and evaporate moisture. Underpads and transfer sheet combinations (grouped by three common linen functions: immobility, moisture management, and immobility and moisture management) were tested using the sweating guarded hot plate method, which allows for the measurement of the evaporative capacity (g H2O/m2*hour) and the total rate of heat withdrawal (Watts/m2) associated with nine different linen configurations placed on the support surface. Total heat withdrawal and evaporative capacity of the LAL surface with a fitted sheet only was used for comparison (P <0.05) Compared with fitted sheet only, heat withdrawal was significantly reduced by five of eight combinations, and evaporative moisture reduction was significantly reduced by six of eight linen combinations (P <0.05). All combinations that included plastic-containing underpads significantly reduced the surface's ability to dissipate heat and evaporate moisture, and use of the maximum number of layers (nine) reduced heat withdrawal to the level of a static, nonLAL surface. The results of this study suggest that putting additional linens or underpads on LAL surfaces may adversely affect skin temperature and moisture, thereby reducing the pressure ulcer prevention potential of these surfaces. Additional studies to examine the effect of linens and underpads as well as microclimate management strategies on pressure ulcer risk are needed.

  8. Heat- and electron-beam-induced transport of gold particles into silicon oxide and silicon studied by in situ high-resolution transmission electron microscopy.

    PubMed

    Biskupek, Johannes; Kaiser, Ute; Falk, Fritz

    2008-06-01

    In this study, we describe the transport of gold (Au) nanoparticles from the surface into crystalline silicon (Si) covered by silicon oxide (SiO(2)) as revealed by in situ high-resolution transmission electron microscopy. Complete crystalline Au nanoparticles sink through the SiO(2) layer into the Si substrate when high-dose electron irradiation is applied and temperature is raised above 150 degrees C. Above temperatures of 250 degrees C, the Au nanoparticles finally dissolve into fragments accompanied by crystallization of the amorphized Si substrate around these fragments. The transport process is explained by a wetting process followed by Stokes motion. Modelling this process yields boundaries for the interface energies involved.

  9. AQUIFER TRANSMISSIVITY

    EPA Science Inventory

    Evaluation of groundwater resources requires the knowledge of the capacity of aquifers to store and transmit ground water. This requires estimates of key hydraulic parameters, such as the transmissivity, among others. The transmissivity T (m2/sec) is a hydrauli...

  10. Automatic transmission

    SciTech Connect

    Miura, M.; Aoki, H.

    1988-02-02

    An automatic transmission is described comprising: an automatic transmission mechanism portion comprising a single planetary gear unit and a dual planetary gear unit; carriers of both of the planetary gear units that are integral with one another; an input means for inputting torque to the automatic transmission mechanism, clutches for operatively connecting predetermined ones of planetary gear elements of both of the planetary gear units to the input means and braking means for restricting the rotation of predetermined ones of planetary gear elements of both of the planetary gear units. The clutches are disposed adjacent one another at an end portion of the transmission for defining a clutch portion of the transmission; a first clutch portion which is attachable to the automatic transmission mechanism portion for comprising the clutch portion when attached thereto; a second clutch portion that is attachable to the automatic transmission mechanism portion in place of the first clutch portion for comprising the clutch portion when so attached. The first clutch portion comprising first clutch for operatively connecting the input means to a ring gear of the single planetary gear unit and a second clutch for operatively connecting the input means to a single gear of the automatic transmission mechanism portion. The second clutch portion comprising a the first clutch, the second clutch, and a third clutch for operatively connecting the input member to a ring gear of the dual planetary gear unit.

  11. AQUIFER TRANSMISSIVITY

    EPA Science Inventory

    Evaluation of groundwater resources requires the knowledge of the capacity of aquifers to store and transmit ground water. This requires estimates of key hydraulic parameters, such as the transmissivity, among others. The transmissivity T (m2/sec) is a hydrauli...

  12. Automated manual transmission clutch controller

    DOEpatents

    Lawrie, Robert E.; Reed, Jr., Richard G.; Rausen, David J.

    1999-11-30

    A powertrain system for a hybrid vehicle. The hybrid vehicle includes a heat engine, such as a diesel engine, and an electric machine, which operates as both an electric motor and an alternator, to power the vehicle. The hybrid vehicle also includes a manual-style transmission configured to operate as an automatic transmission from the perspective of the driver. The engine and the electric machine drive an input shaft which in turn drives an output shaft of the transmission. In addition to driving the transmission, the electric machine regulates the speed of the input shaft in order to synchronize the input shaft during either an upshift or downshift of the transmission by either decreasing or increasing the speed of the input shaft. When decreasing the speed of the input shaft, the electric motor functions as an alternator to produce electrical energy which may be stored by a storage device. Operation of the transmission is controlled by a transmission controller which receives input signals and generates output signals to control shift and clutch motors to effect smooth launch, upshift shifts, and downshifts of the transmission, so that the transmission functions substantially as an automatic transmission from the perspective of the driver, while internally substantially functioning as a manual transmission.

  13. Quantifying Transmission.

    PubMed

    Woolhouse, Mark

    2017-07-01

    Transmissibility is the defining characteristic of infectious diseases. Quantifying transmission matters for understanding infectious disease epidemiology and designing evidence-based disease control programs. Tracing individual transmission events can be achieved by epidemiological investigation coupled with pathogen typing or genome sequencing. Individual infectiousness can be estimated by measuring pathogen loads, but few studies have directly estimated the ability of infected hosts to transmit to uninfected hosts. Individuals' opportunities to transmit infection are dependent on behavioral and other risk factors relevant given the transmission route of the pathogen concerned. Transmission at the population level can be quantified through knowledge of risk factors in the population or phylogeographic analysis of pathogen sequence data. Mathematical model-based approaches require estimation of the per capita transmission rate and basic reproduction number, obtained by fitting models to case data and/or analysis of pathogen sequence data. Heterogeneities in infectiousness, contact behavior, and susceptibility can have substantial effects on the epidemiology of an infectious disease, so estimates of only mean values may be insufficient. For some pathogens, super-shedders (infected individuals who are highly infectious) and super-spreaders (individuals with more opportunities to transmit infection) may be important. Future work on quantifying transmission should involve integrated analyses of multiple data sources.

  14. Power transmission

    SciTech Connect

    Yale, O.S.

    1989-12-12

    This patent describes a power transmission. It comprises: in combination, a master gear having at least one annular tooth set, means for drivingly engaging the master gear with a power source, driven shaft, a yoke member attached to the shaft and including a screw pump housing extending radially with respect to the shaft with a pair of ports in spaced relation, a pump screw rotatable in the housing and a pump gear attached to the screw and engaging the annular tooth set, and a casing for transmission fluid. The pump housing being located for immersion in the fluid.

  15. HIV Transmission

    MedlinePlus

    ... Abroad Treatment Basic Statistics Get Tested Find an HIV testing site near you. Enter ZIP code or city Follow HIV/AIDS CDC HIV CDC HIV/AIDS See RSS | ... on HIV Syndicated Content Website Feedback HIV/AIDS HIV Transmission Language: English (US) Español (Spanish) Recommend ...

  16. Television Transmission Technology

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The VKP-7990 Multistage Depressed Collector (MDC) Klystron is a result of cooperative development by Varian Associates, Inc., the National Association of Broadcasters, Lewis Research Center, the Public Broadcasting System and TV transmitter manufacturers. The effort was initiated to make power amplifying devices with efficiencies comparable to VHF available to UHF operators. The klystron is a vacuum tube used to generate and amplify ultrahigh frequencies but at low efficiencies because most of the energy is dissipated as waste heat. Lewis had earlier developed the MDC to enhance the efficiency of communications satellite transmissions. Varian Microwave Power Tube Products, which has since become Communications and Power Industries, and Lewis combined the MDC and the klystron, resulting in a product which increases efficiency by recovering some of the residual energy that normally would be lost as heat. The MDC klystron cuts the electric power consumption of UHF-TV transmitters in half; there are 90 units in operation in 36 UHF-TV stations.

  17. Rotorcraft transmission

    NASA Technical Reports Server (NTRS)

    Coy, John J.

    1987-01-01

    The NASA Lewis Research Center and the U.S. Army Aviation Systems Command share an interest in advancing the technology for helicopter propulsion systems. In particular, this presentation outlines that portion of the program that applies to the drive train and its various mechanical components. The major goals of the program are to increase the life, reliability, and maintainability; reduce the weight, noise, and vibration; and maintain the relatively high mechanical efficiency of the gear train. The current activity emphasizes noise reduction technology and analytical code development followed by experimental verification. Selected significant advances in technology for transmissions are reviewed, including advanced configurations and new analytical tools. Finally, the plan for transmission research in the future is presented.

  18. Heat pipe array heat exchanger

    DOEpatents

    Reimann, Robert C.

    1987-08-25

    A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

  19. Automatic transmission

    SciTech Connect

    Miki, N.

    1988-10-11

    This patent describes an automatic transmission including a fluid torque converter, a first gear unit having three forward-speed gears and a single reverse gear, a second gear unit having a low-speed gear and a high-speed gear, and a hydraulic control system, the hydraulic control system comprising: a source of pressurized fluid; a first shift valve for controlling the shifting between the first-speed gear and the second-speed gear of the first gear unit; a second shift valve for controlling the shifting between the second-speed gear and the third-speed gear of the first gear unit; a third shift valve equipped with a spool having two positions for controlling the shifting between the low-speed gear and the high-speed gear of the second gear unit; a manual selector valve having a plurality of shift positions for distributing the pressurized fluid supply from the source of pressurized fluid to the first, second and third shift valves respectively; first, second and third solenoid valves corresponding to the first, second and third shift valves, respectively for independently controlling the operation of the respective shift valves, thereby establishing a six forward-speed automatic transmission by combining the low-speed gear and the high-speed gear of the second gear unit with each of the first-speed gear, the second speed gear and the third-speed gear of the first gear unit; and means to fixedly position the spool of the third shift valve at one of the two positions by supplying the pressurized fluid to the third shift valve when the manual selector valve is shifted to a particular shift position, thereby locking the second gear unit in one of low-speed gear and the high-speed gear, whereby the six forward-speed automatic transmission is converted to a three forward-speed automatic transmission when the manual selector valve is shifted to the particular shift position.

  20. Automatic transmission

    SciTech Connect

    Ohkubo, M.

    1988-02-16

    An automatic transmission is described combining a stator reversing type torque converter and speed changer having first and second sun gears comprising: (a) a planetary gear train composed of first and second planetary gears sharing one planetary carrier in common; (b) a clutch and requisite brakes to control the planetary gear train; and (c) a speed-increasing or speed-decreasing mechanism is installed both in between a turbine shaft coupled to a turbine of the stator reversing type torque converter and the first sun gear of the speed changer, and in between a stator shaft coupled to a reversing stator and the second sun gear of the speed changer.

  1. Transmission Investment: A Primer

    SciTech Connect

    McGarvey, Joe

    2006-10-15

    This primer highlights recent trends in transmission investment, summarizes the division of jurisdictional authority over transmission, and presents four alternative models for transmission ownership. (author)

  2. Automatic transmission

    SciTech Connect

    Aoki, H.

    1989-03-21

    An automatic transmission is described, comprising: a torque converter including an impeller having a connected member, a turbine having an input member and a reactor; and an automatic transmission mechanism having first to third clutches and plural gear units including a single planetary gear unit with a ring gear and a dual planetary gear unit with a ring gear. The single and dual planetary gear units have respective carriers integrally coupled with each other and respective sun gears integrally coupled with each other, the input member of the turbine being coupled with the ring gear of the single planetary gear unit through the first clutch, and being coupled with the sun gear through the second clutch. The connected member of the impeller is coupled with the ring gear of the dual planetary gear of the dual planetary gear unit is made to be and ring gear of the dual planetary gear unit is made to be restrained as required, and the carrier is coupled with an output member.

  3. Vented transmission

    SciTech Connect

    Nguyen, T.H.

    1990-01-29

    This patent describes a vented transmission. It comprises: a housing; a rotary input to the housing; a rotary output from the housing; transmission means within the housing interconnecting the input and the output and including a hollow, rotary shaft journaled within the housing; a vent tube having a first end extending into one end of the hollow shaft and a second end in fluid communication with the exterior of the housing; a shoulder within the hollow shaft and intermediate the ends of the vent tube and defining of relatively smaller diameter section near the first end of the vent tube that is within the hollow shaft and a relatively large diameter section nearer the second end of the vent tube; at least one aperture extending through the hollow shaft from the large diameter section immediately adjacent the shoulder; and a labyrinth seal at the interface of the vent tube and the large diameter section at a location between the aperture (s) and the second end of the vent tube.

  4. Gear transmission

    SciTech Connect

    Takami, A.

    1987-08-11

    A gear transmission is provided with a first rotary shaft, a first non-circular gear fixed thereto, a second rotary shaft, and a second non-circular gear fixed thereto, the first non-circular gear and the second non-circular gear being continuously engageably rotated, thereby transmitting a rotational driving force between the first rotary shaft and the second rotary shaft. The gear transmission is characterized in that when the absolute value vertical bar..omega..2/..omega..1vertical bar of a ratio of an angular velocity of ..omega..2 of the second rotary shaft with respect to an angular velocity of ..omega..1 of the first rotary shaft is represented by F(theta) as the function of the angular displacement theta of the first rotary shaft, an engageably rotary portion where a differential value K given in a differential equation as to the angular displacement thetaK=d log F(theta)/dtheta presents a positive or negative constant value in continuation is provided in the shape of intermeshing pitch curves of the first non-circular gear and the second non-circular gear.

  5. Automatic transmission

    SciTech Connect

    Meyman, U.

    1987-03-10

    An automatic transmission is described comprising wheel members each having discs defining an inner space therebetween; turnable blades and vane members located in the inner space between the discs of at least one of the wheel members, the turnable blades being mechanically connected with the vane members. Each of the turnable blades has an inner surface and an outer surface formed by circular cylindrical surfaces having a common axis, each of the turnable blades being turnable about the common axis of the circular cylindrical surfaces forming the inner and outer surfaces of the respective blade; levers turnable about the axes and supporting the blades; the discs having openings extending coaxially with the surfaces which describe the blades. The blades are partially received in the openings of the discs; and a housing accommodating the wheel members and the turnable blades and the vane members.

  6. Automatic transmission

    SciTech Connect

    Hamane, M.; Ohri, H.

    1989-03-21

    This patent describes an automatic transmission connected between a drive shaft and a driven shaft and comprising: a planetary gear mechanism including a first gear driven by the drive shaft, a second gear operatively engaged with the first gear to transmit speed change output to the driven shaft, and a third gear operatively engaged with the second gear to control the operation thereof; centrifugally operated clutch means for driving the first gear and the second gear. It also includes a ratchet type one-way clutch for permitting rotation of the third gear in the same direction as that of the drive shaft but preventing rotation in the reverse direction; the clutch means comprising a ratchet pawl supporting plate coaxially disposed relative to the drive shaft and integrally connected to the third gear, the ratchet pawl supporting plate including outwardly projection radial projections united with one another at base portions thereof.

  7. Planetary transmission

    SciTech Connect

    Nerstad, K.A.; Windish, W.E.

    1987-04-21

    A planetary transmission is described comprising: an input shaft; a first planetary gear set having a first sun gear driven by the input shaft, a first planet carrier serving as the output, a first ring gear, and first brake means for selectively holding the fist ring gear stationary; a second planetary gear set having a second sun gear driven by the input shaft, a second planet carrier connected for joint rotation to the first ring gear, a second ring gear, and second brake means for selectively holding the second ring gear stationary; a third planetary gear set having a third sun gear connected for joint rotation to the second planet carrier, a third planet carrier connected for joint rotation to the second ring gear, a third ring gear, and third brake means for selectively holding the third ring gear stationary; and clutch means for connecting the third sun gear to the input shaft and providing a direct drive mode of operation.

  8. Overdrive transmission

    SciTech Connect

    Miller, G.F.

    1986-02-04

    This patent describes an overdrive transmission device for use with a motor vehicle. It consists of: a housing; a driving shaft rotatably mounted within the housing; a planetary gear-train; a driven shaft rotatably mounted in the housing and driven by the planetary gear train; and, a device for selectively connecting the planetary gear carrier to the housing or to the driven shaft for rotation; a hydraulically actuated piston adapted to forcibly contact the clutch friction members of the second clutch; a source of working fluid; a pump in fluid flow communication with the source of working fluid; a first valve downstream of the pump and in fluid flow communication with the pump and the hydraulically activated piston.

  9. Phasing transmission

    SciTech Connect

    Himmelein, M.K.; Haaser, J.D.

    1992-06-23

    This patent describes a mechanical power transmission. It comprises a pair of axially aligned rotatable shaft members, a motor member, having a motor housing of thin axial width located within the central housing, fixed to one of the shaft members and axially aligned to rotate wherewith, and a harmonic drive member of thin axial width positioned within the central housing in axial alignment between the motor member and the remaining shaft member, a circular spline fixed to the motor housing for rotation therewith, a flex spline engaged with the dynamic spline and the circular spline, and a wave generator in communication with the flex spline and a wave generator in communication with the flex spline and engaged with the center shaft of the motor member.

  10. Hydromechanical transmission

    DOEpatents

    Orshansky, Jr. deceased, Elias; Weseloh, William E.

    1978-01-01

    A power transmission having three planetary assemblies, each having its own carrier and its own planet, sun, and ring gears. A speed-varying module is connected in driving relation to the input shaft and in driving relationship to the three sun gears, all of which are connected together. The speed-varying means may comprise a pair of hydraulic units hydraulically interconnected so that one serves as a pump while the other serves as a motor and vice versa, one of the units having a variable stroke and being connected in driving relation to the input shaft, the other unit, which may have a fixed stroke, being connected in driving relation to the sun gears. The input shaft also drives the carrier of the third planetary assembly. A brake grounds the first carrier in the first range and in reverse and causes drive to be delivered to the output through the first ring gear in a hydrostatic mode. The carrier of the third planetary assembly drives the ring gear of the second planetary assembly, and a first clutching means connects the second carrier with the output in a second range, the brake for grounding the first carrier then being released. A second clutching means enables the third ring gear to drive the output shaft in a third range.

  11. Flywheel electric transmission apparatus

    SciTech Connect

    Bock, D.H.

    1982-01-05

    In a preferred embodiment, the flywheel electric transmission system is made up of three electric machines and a flywheel and is adapted for use in an automobile. The first electric machine is driven or energized by a prime mover such as a heat engine and is selectively clutched to the second machine. The flywheel and the armatures for both the first and second machines rotate as a unit. The third machine is connected to the second machine through gearing and, under the control of a computer, supplies excess electrical power to or consumes excess electrical power from the first and second machines that are functioning as either a motor or generator as required. In a second embodiment, the energy source is a battery pack.

  12. 24 CFR 3280.506 - Heat loss/heat gain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.506 Heat... assure uniform heat transmission in manufactured homes, cavities in exterior walls, floors, and ceilings shall be provided with thermal insulation. (c) Manufactured homes designed for Uo Value Zone 3 shall...

  13. Power transmission

    SciTech Connect

    Ordo, J.P.; Raszkowski, J.A.; Klemen, D.

    1991-04-23

    This patent describes a transmission. It comprises a housing having first and second end covers; an input shaft rotatably mounted in the first end cover; an output shaft rotatably supported on the input shaft and in the second end cover; first and second countershafts rotatably supported in the end covers for rotation on respective axis parallel with the input shaft and the output shaft; a first head gear continuously rotatable with the input shaft; second and third head gears meshing with the first head gear and continuously rotatable with the first and second countershafts respectively; ratio gears rotatably supported on each of the countershafts including a first ratio gear on the first countershaft and a second ratio gear on the second countershaft; reverse gear means including a first ratio gear on the first countershaft and a second ratio gear on the second countershaft; reverse gear means including a first member rotatable with the first ratio gear means including a first member rotatable with the first ratio gear and a second member rotatably supported on the second countershaft; synchronizer clutch means selectively and alternatively connectible with the second ratio gear and the second member of the reverse gear means; output gear means drivingly connected with the output shaft and including a first ratio output gear meshing with the second ratio gear; first selectively engageable friction clutch means for connecting the first ratio gear with the first countershaft for completing a low forward drive ratio between the input and output shafts; and second selectively engageable friction clutch means for selectively connecting the synchronizer clutch means to the second countershaft and cooperating therewith to selectively alternatively complete a reverse drive ratio between the input shaft and the output shaft and another forward drive ratio between the input and output shafts.

  14. Automatic transmission

    SciTech Connect

    Miura, M.; Inuzuka, T.

    1986-08-26

    1. An automatic transmission with four forward speeds and one reverse position, is described which consists of: an input shaft; an output member; first and second planetary gear sets each having a sun gear, a ring gear and a carrier supporting a pinion in mesh with the sun gear and ring gear; the carrier of the first gear set, the ring gear of the second gear set and the output member all being connected; the ring gear of the first gear set connected to the carrier of the second gear set; a first clutch means for selectively connecting the input shaft to the sun gear of the first gear set, including friction elements, a piston selectively engaging the friction elements and a fluid servo in which hydraulic fluid is selectively supplied to the piston; a second clutch means for selectively connecting the input shaft to the sun gear of the second gear set a third clutch means for selectively connecting the input shaft to the carrier of the second gear set including friction elements, a piston selectively engaging the friction elements and a fluid servo in which hydraulic fluid is selectively supplied to the piston; a first drive-establishing means for selectively preventing rotation of the ring gear of the first gear set and the carrier of the second gear set in only one direction and, alternatively, in any direction; a second drive-establishing means for selectively preventing rotation of the sun gear of the second gear set; and a drum being open to the first planetary gear set, with a cylindrical intermediate wall, an inner peripheral wall and outer peripheral wall and forming the hydraulic servos of the first and third clutch means between the intermediate wall and the inner peripheral wall and between the intermediate wall and the outer peripheral wall respectively.

  15. Automated manual transmission shift sequence controller

    DOEpatents

    Lawrie, Robert E.; Reed, Richard G.; Rausen, David J.

    2000-02-01

    A powertrain system for a hybrid vehicle. The hybrid vehicle includes a heat engine, such as a diesel engine, and an electric machine, which operates as both, an electric motor and an alternator, to power the vehicle. The hybrid vehicle also includes a manual-style transmission configured to operate as an automatic transmission from the perspective of the driver. The engine and the electric machine drive an input shaft which in turn drives an output shaft of the transmission. In addition to driving the transmission, the electric machine regulates the speed of the input shaft in order to synchronize the input shaft during either an upshift or downshift of the transmission by either decreasing or increasing the speed of the input shaft. When decreasing the speed of the input shaft, the electric motor functions as an alternator to produce electrical energy which may be stored by a storage device. Operation of the transmission is controlled by a transmission controller which receives input signals and generates output signals to control shift and clutch motors to effect smooth launch, upshift shifts, and downshifts of the transmission, so that the transmission functions substantially as an automatic transmission from the perspective of the driver, while internally substantially functioning as a manual transmission.

  16. Automated manual transmission mode selection controller

    DOEpatents

    Lawrie, Robert E.

    1999-11-09

    A powertrain system for a hybrid vehicle. The hybrid vehicle includes a heat engine, such as a diesel engine, and an electric machine, which operates as both an electric motor and an alternator, to power the vehicle. The hybrid vehicle also includes a manual-style transmission configured to operate as an automatic transmission from the perspective of the driver. The engine and the electric machine drive an input shaft which in turn drives an output shaft of the transmission. In addition to driving the transmission, the electric machine regulates the speed of the input shaft in order to synchronize the input shaft during either an upshift or downshift of the transmission by either decreasing or increasing the speed of the input shaft. When decreasing the speed of the input shaft, the electric motor functions as an alternator to produce electrical energy which may be stored by a storage device. Operation of the transmission is controlled by a transmission controller which receives input signals and generates output signals to control shift and clutch motors to effect smooth launch, upshift shifts, and downshifts of the transmission, so that the transmission functions substantially as an automatic transmission from the perspective of the driver, while internally substantially functioning as a manual transmission.

  17. Heat Islands

    EPA Pesticide Factsheets

    EPA's Heat Island Effect Site provides information on heat islands, their impacts, mitigation strategies, related research, a directory of heat island reduction initiatives in U.S. communities, and EPA's Heat Island Reduction Program.

  18. Heat accumulator

    SciTech Connect

    Bracht, A.

    1981-09-29

    A heat accumulator comprises a thermally-insulated reservoir full of paraffin wax mixture or other flowable or meltable heat storage mass, heat-exchangers immersed in the mass, a heat-trap connected to one of the heat-exchangers, and a heat user connected to the other heat-exchanger. Pumps circulate fluids through the heat-trap and the heat-using means and the respective heat-exchangers, and a stirrer agitates and circulates the mass, and the pumps and the stirrer and electric motors driving these devices are all immersed in the mass.

  19. Survey of Transmission Cost Allocation Methodologies for Regional Transmission Organizations

    SciTech Connect

    Fink, S.; Porter, K.; Mudd, C.; Rogers, J.

    2011-02-01

    The report presents transmission cost allocation methodologies for reliability transmission projects, generation interconnection, and economic transmission projects for all Regional Transmission Organizations.

  20. Earth-coupled heat pump

    NASA Astrophysics Data System (ADS)

    Edwards, J. A.

    1981-08-01

    The object of the research work was to demonstrate that a water source heat pump could be used with an earth-coupled heat exchanger which was buried in an absorption field of a domestic sewage disposal system to provide the heating and cooling requirements for residential use in an energy efficient fashion. The system consists of a 3 ton heat pump (nominal rating of 34,000 Btu/hr), a closed-loop heat exchanger which was fabricated from 200 feet of 2 inch diameter cast iron soil pipe, and a calorimeter house which had heat transmission characteristics similar to a 100 sq ft house. The earth-coupled heat exchanger was connected to the water side heat exchanger of the heat pump. Water was circulated through the heat exchanger coil in the earth and through the water side heat exchanger of the heat pump. The earth served as the energy source (for heating) or sink (for cooling) for the heat pump.

  1. Heat pumps

    NASA Astrophysics Data System (ADS)

    Gilli, P. V.

    1982-11-01

    Heat pumps for residential/commercial space heating and hot tap water make use of free energy of direct or indirect solar heat and save from about 40 to about 70 percent of energy if compared to a conventional heating system with the same energy basis. In addition, the electrically driven compressor heat pump is able to substitute between 40% (bivalent alternative operation) to 100% (monovalent operation) of the fuel oil of an oilfired heating furnace. For average Central European conditions, solar space heating systems with high solar coverage factor show the following sequence of increasing cost effectiveness: pure solar systems (without heat pumps); heat pump assisted solar systems; solar assisted heat pump systems; subsoil/water heat pumps; air/water heat pumps; air/air heat pumps.

  2. Heat Without Heat

    NASA Astrophysics Data System (ADS)

    Lubkin, Elihu

    1997-04-01

    Logic of the Second Law of Thermodynamics demands acquisition of naked entropy. Accordingly, the leanest liaison between systems is not a diathermic membrane, it is a purely informational tickler, leaking no appreciable energy. The subsystem here is a thermodynamic universe, which gets `heated' entropically, yet without gaining calories. Quantum Mechanics graciously supports that(Lubkin, E. and Lubkin, T., International Journal of Theoretical Physics,32), 933-943 (1993) (at a cost of about 1 bit) through entanglement---across this least permeable of membranes---with what is beyond that universe. Heat without heat(Also v. forthcoming Proceedings of the 4th Drexel University Conference of September 1994) is the aspirin for Boltzmann's headache, conserving entropy in mechanical isolation, even while increasing entropy in thermodynamic isolation.

  3. Heat Pipes

    ERIC Educational Resources Information Center

    Lewis, J.

    1975-01-01

    Describes the construction, function, and applications of heat pipes. Suggests using the heat pipe to teach principles related to heat transfer and gives sources for obtaining instructional kits for this purpose. (GS)

  4. Heat Stress

    MedlinePlus

    ... Work in the Heat: Why Acclimatization Matters The natural adaptation to the heat takes time, and from a management perspective, it may require careful planning. NIOSH Science Blog: Extreme Heat – Are you prepared for summer ...

  5. Manual with auxiliary transmission

    SciTech Connect

    Nishimura, S.

    1987-06-23

    This patent describes a vehicular transmission of the type in which a manual transmission has two parallel shafts. One shaft is connected through a transmission clutch to an engine in which manual transmission is connected in series to an auxiliary transmission having high and low speed transmission lines. The auxiliary transmission has a high speed transmission line equipped with a hydraulic clutch and a low speed transmission line equipped with a one-way clutch for allowing the overrun of the output side of the low speed transmission line so that the low speed transmission line is established when the hydraulic clutch is released. The high speed transmission is established when the hydraulic clutch is applied. A sleeve shaft is on one of the two shafts. A transmission gear mechanism connects the sleeve shaft to the other shaft. One shaft has an extension with a fixed gear. A coacting gear is fixed on the sleeve shaft, the hydraulic clutch and coacting gear positioned on the extension of one shaft, an idle gear mechanism in meshing engagement with both the coacting gear and the fixed gear. The idle gear mechanism has a low speed transmission line one-way clutch, and the hydraulic clutch is operable to connect and disconnect the sleeve shaft to and from the one shaft.

  6. EC Transmission Line Materials

    SciTech Connect

    Bigelow, Tim S

    2012-05-01

    The purpose of this document is to identify materials acceptable for use in the US ITER Project Office (USIPO)-supplied components for the ITER Electron cyclotron Heating and Current Drive (ECH&CD) transmission lines (TL), PBS-52. The source of material property information for design analysis shall be either the applicable structural code or the ITER Material Properties Handbook. In the case of conflict, the ITER Material Properties Handbook shall take precedence. Materials selection, and use, shall follow the guidelines established in the Materials Assessment Report (MAR). Materials exposed to vacuum shall conform to the ITER Vacuum Handbook. [Ref. 2] Commercial materials shall conform to the applicable standard (e.g., ASTM, JIS, DIN) for the definition of their grade, physical, chemical and electrical properties and related testing. All materials for which a suitable certification from the supplier is not available shall be tested to determine the relevant properties, as part of the procurement. A complete traceability of all the materials including welding materials shall be provided. Halogenated materials (example: insulating materials) shall be forbidden in areas served by the detritiation systems. Exceptions must be approved by the Tritium System and Safety Section Responsible Officers.

  7. Virus transmission via food.

    PubMed

    Cliver, D O

    1997-01-01

    Viruses are transmitted to humans via foods as a result of direct or indirect contamination of the foods with human faeces. Viruses transmitted by a faecal-oral route are not strongly dependent on foods as vehicles of transmission, but viruses are important among agents of foodborne disease. Vehicles are most often molluscs from contaminated waters, but many other foods are contaminated directly by infected persons. The viruses most often foodborne are the hepatitis A virus and the Norwalk-like gastroenteritis viruses. Detection methods for these viruses in foods are very difficult and costly; the methods are not routine. Indicators that would rapidly and reliably suggest the presence of viral contamination of foods are still being sought. Contamination can be prevented by keeping faeces out of food or by treating vehicles such as water in order to inactivate virus that might be carried to food in this way. Virus cannot multiply in food, but can usually be inactivated by adequate heating. Other methods of inactivating viruses within a food are relatively unreliable, but viruses in water and on exposed surfaces can be inactivated with ultraviolet light or with strong oxidizing agents.

  8. Transmission diamond imaging detector

    SciTech Connect

    Smedley, John Pinelli, Don; Gaoweia, Mengjia; Muller, Erik; Ding, Wenxiang; Zhou, Tianyi; Bohon, Jen

    2016-07-27

    Many modern synchrotron techniques are trending toward use of high flux beams and/or beams which require enhanced stability and precise understanding of beam position and intensity from the front end of the beamline all the way to the sample. For high flux beams, major challenges include heat load management in optics (including the vacuum windows) and a mechanism of real-time volumetric measurement of beam properties such as flux, position, and morphology. For beam stability in these environments, feedback from such measurements directly to control systems for optical elements or to sample positioning stages would be invaluable. To address these challenges, we are developing diamond-based instrumented vacuum windows with integrated volumetric x-ray intensity, beam profile and beam-position monitoring capabilities. A 50 µm thick single crystal diamond has been lithographically patterned to produce 60 µm pixels, creating a >1kilopixel free-standing transmission imaging detector. This device, coupled with a custom, FPGA-based readout, has been used to image both white and monochromatic x-ray beams and capture the last x-ray photons at the National Synchrotron Light Source (NSLS). This technology will form the basis for the instrumented end-station window of the x-ray footprinting beamline (XFP) at NSLS-II.

  9. Zika and Sexual Transmission

    MedlinePlus

    ... Address What's this? Submit What's this? Submit Button Zika and Sexual Transmission Language: English Español Português ... 1 page] Portuguese [PDF - 1 page] Basics of Zika Virus and Sex Transmission Zika can be passed ...

  10. Automatic transmission adapter kit

    SciTech Connect

    Stich, R.L.; Neal, W.D.

    1987-02-10

    This patent describes, in a four-wheel-drive vehicle apparatus having a power train including an automatic transmission and a transfer case, an automatic transmission adapter kit for installation of a replacement automatic transmission of shorter length than an original automatic transmission in the four-wheel-drive vehicle. The adapter kit comprises: an extension housing interposed between the replacement automatic transmission and the transfer case; an output shaft, having a first end which engages the replacement automatic transmission and a second end which engages the transfer case; first sealing means for sealing between the extension housing and the replacement automatic transmission; second sealing means for sealing between the extension housing and the transfer case; and fastening means for connecting the extension housing between the replacement automatic transmission and the transfer case.

  11. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Comfort heat gain. 3280.507 Section... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss...

  12. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Comfort heat gain. 3280.507 Section... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss...

  13. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Comfort heat gain. 3280.507 Section... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss...

  14. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Comfort heat gain. 3280.507 Section... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss...

  15. Effects of the distribution density of a biomass combined heat and power plant network on heat utilisation efficiency in village-town systems.

    PubMed

    Zhang, Yifei; Kang, Jian

    2017-11-01

    The building of biomass combined heat and power (CHP) plants is an effective means of developing biomass energy because they can satisfy demands for winter heating and electricity consumption. The purpose of this study was to analyse the effect of the distribution density of a biomass CHP plant network on heat utilisation efficiency in a village-town system. The distribution density is determined based on the heat transmission threshold, and the heat utilisation efficiency is determined based on the heat demand distribution, heat output efficiency, and heat transmission loss. The objective of this study was to ascertain the optimal value for the heat transmission threshold using a multi-scheme comparison based on an analysis of these factors. To this end, a model of a biomass CHP plant network was built using geographic information system tools to simulate and generate three planning schemes with different heat transmission thresholds (6, 8, and 10 km) according to the heat demand distribution. The heat utilisation efficiencies of these planning schemes were then compared by calculating the gross power, heat output efficiency, and heat transmission loss of the biomass CHP plant for each scenario. This multi-scheme comparison yielded the following results: when the heat transmission threshold was low, the distribution density of the biomass CHP plant network was high and the biomass CHP plants tended to be relatively small. In contrast, when the heat transmission threshold was high, the distribution density of the network was low and the biomass CHP plants tended to be relatively large. When the heat transmission threshold was 8 km, the distribution density of the biomass CHP plant network was optimised for efficient heat utilisation. To promote the development of renewable energy sources, a planning scheme for a biomass CHP plant network that maximises heat utilisation efficiency can be obtained using the optimal heat transmission threshold and the nonlinearity

  16. Data transmission element for downhole drilling components

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Fox, Joe; Sneddon, Cameron; Briscoe, Michael

    2006-01-31

    A robust data transmission element for transmitting information between downhole components, such as sections of drill pipe, in the presence of hostile environmental conditions, such as heat, dirt, rocks, mud, fluids, lubricants, and the like. The data transmission element components include a generally U-shaped annular housing, a generally U-shaped magnetically conductive, electrically insulating element such as ferrite, and an insulated conductor. Features on the magnetically conducting, electrically insulating element and the annular housing create a pocket when assembled. The data transmission element is filled with a polymer to retain the components within the annular housing by filling the pocket with the polymer. The polymer can bond with the annular housing and the insulated conductor but preferably not the magnetically conductive, electrically insulating element. A data transmission element is mounted within a recess proximate a mating surface of a downhole drilling component, such as a section of drill pipe.

  17. Bordetella pertussis transmission.

    PubMed

    Trainor, Elizabeth A; Nicholson, Tracy L; Merkel, Tod J

    2015-11-01

    Bordetella pertussis and B. bronchiseptica are Gram-negative bacterial respiratory pathogens. Bordetella pertussis is the causative agent of whooping cough and is considered a human-adapted variant of B. bronchiseptica. Bordetella pertussis and B. bronchiseptica share mechanisms of pathogenesis and are genetically closely related. However, despite the close genetic relatedness, these Bordetella species differ in several classic fundamental aspects of bacterial pathogens such as host range, pathologies and persistence. The development of the baboon model for the study of B. pertussis transmission, along with the development of the swine and mouse model for the study of B. bronchiseptica, has enabled the investigation of different aspects of transmission including the route, attack rate, role of bacterial and host factors, and the impact of vaccination on transmission. This review will focus on B. pertussis transmission and how animal models of B. pertussis transmission and transmission models using the closely related B. bronchiseptica have increased our understanding of B. pertussis transmission.

  18. Heat exchanger

    DOEpatents

    Daman, Ernest L.; McCallister, Robert A.

    1979-01-01

    A heat exchanger is provided having first and second fluid chambers for passing primary and secondary fluids. The chambers are spaced apart and have heat pipes extending from inside one chamber to inside the other chamber. A third chamber is provided for passing a purge fluid, and the heat pipe portion between the first and second chambers lies within the third chamber.

  19. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Heat Pipes were originally developed by NASA and the Los Alamos Scientific Laboratory during the 1960s to dissipate excessive heat build- up in critical areas of spacecraft and maintain even temperatures of satellites. Heat pipes are tubular devices where a working fluid alternately evaporates and condenses, transferring heat from one region of the tube to another. KONA Corporation refined and applied the same technology to solve complex heating requirements of hot runner systems in injection molds. KONA Hot Runner Systems are used throughout the plastics industry for products ranging in size from tiny medical devices to large single cavity automobile bumpers and instrument panels.

  20. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Phoenix Refrigeration Systems, Inc.'s heat pipe addition to the Phoenix 2000, a supermarket rooftop refrigeration/air conditioning system, resulted from the company's participation in a field test of heat pipes. Originally developed by NASA to control temperatures in space electronic systems, the heat pipe is a simple, effective, heat transfer system. It has been used successfully in candy storage facilities where it has provided significant energy savings. Additional data is expected to fully quantify the impact of the heat pipes on supermarket air conditioning systems.

  1. Method for controlling exhaust gas heat recovery systems in vehicles

    DOEpatents

    Spohn, Brian L.; Claypole, George M.; Starr, Richard D

    2013-06-11

    A method of operating a vehicle including an engine, a transmission, an exhaust gas heat recovery (EGHR) heat exchanger, and an oil-to-water heat exchanger providing selective heat-exchange communication between the engine and transmission. The method includes controlling a two-way valve, which is configured to be set to one of an engine position and a transmission position. The engine position allows heat-exchange communication between the EGHR heat exchanger and the engine, but does not allow heat-exchange communication between the EGHR heat exchanger and the oil-to-water heat exchanger. The transmission position allows heat-exchange communication between the EGHR heat exchanger, the oil-to-water heat exchanger, and the engine. The method also includes monitoring an ambient air temperature and comparing the monitored ambient air temperature to a predetermined cold ambient temperature. If the monitored ambient air temperature is greater than the predetermined cold ambient temperature, the two-way valve is set to the transmission position.

  2. Transmission Planning Analysis Tool

    SciTech Connect

    2015-06-23

    Developed to solve specific problem: Assist transmission planning for regional transfers in interconnected power systems. This work was originated in a study for the U.S. Department of State, to recommend transmission reinforcements for the Central American regional system that interconnects 6 countries. Transmission planning analysis is currently performed by engineers with domainspecific and systemspecific knowledge without a unique methodology. The software codes of this disclosure assists engineers by defining systematic analysis procedures to help identify weak points and make decisions on transmission planning of regional interconnected power systems. Transmission Planning Analysis Tool groups PSS/E results of multiple AC contingency analysis and voltage stability analysis and QV analysis of many scenarios of study and arrange them in a systematic way to aid power system planning engineers or transmission operators in effective decision]making process or in the off]line study environment.

  3. Series Transmission Line Transformer

    DOEpatents

    Buckles, Robert A.; Booth, Rex; Yen, Boris T.

    2004-06-29

    A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

  4. Understanding Ebola Virus Transmission

    PubMed Central

    Judson, Seth; Prescott, Joseph; Munster, Vincent

    2015-01-01

    An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fill these voids in our knowledge about the transmission of Ebola virus. PMID:25654239

  5. Understanding ebola virus transmission.

    PubMed

    Judson, Seth; Prescott, Joseph; Munster, Vincent

    2015-02-03

    An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fill these voids in our knowledge about the transmission of Ebola virus.

  6. Fluctuation of heat current in Josephson junctions

    SciTech Connect

    Virtanen, P.; Giazotto, F.

    2015-02-15

    We discuss the statistics of heat current between two superconductors at different temperatures connected by a generic weak link. As the electronic heat in superconductors is carried by Bogoliubov quasiparticles, the heat transport fluctuations follow the Levitov–Lesovik relation. We identify the energy-dependent quasiparticle transmission probabilities and discuss the resulting probability density and fluctuation relations of the heat current. We consider multichannel junctions, and find that heat transport in diffusive junctions is unique in that its statistics is independent of the phase difference between the superconductors.

  7. Transmission Line Security Monitor

    ScienceCinema

    None

    2016-07-12

    The Transmission Line Security Monitor is a multi-sensor monitor that mounts directly on high-voltage transmission lines to detect, characterize and communicate terrorist activity, human tampering and threatening conditions around support towers. For more information about INL's critical infrastructure protection research, visit http://www.facebook.com/idahonationallaboratory.

  8. Transmission Line Security Monitor

    SciTech Connect

    2011-01-01

    The Transmission Line Security Monitor is a multi-sensor monitor that mounts directly on high-voltage transmission lines to detect, characterize and communicate terrorist activity, human tampering and threatening conditions around support towers. For more information about INL's critical infrastructure protection research, visit http://www.facebook.com/idahonationallaboratory.

  9. Data Transmission Concepts.

    ERIC Educational Resources Information Center

    Christenson, Chris

    1995-01-01

    Introduces some basic concepts related to the transmission of data from a computer to its peripherals to help distance educators make decisions regarding computer equipment purchases for their institutions. The following data transmission concepts are described: cables, serial and parallel, synchronous and asynchronous, bandwidth, and analog and…

  10. Passenger car transmissions

    SciTech Connect

    Not Available

    1990-01-01

    This book is organized under the following headings. The Mercedes-Benz 5-speed automatic transmission targets and comparison of concepts. 1991 model year Chrysler mini-van all wheel drive vehicle. Mesh stiffness and transmission error of spur and helical gears. High precision cutting tool system for the manufacture of world class powertrain components.

  11. Heating apparatus

    SciTech Connect

    Woo, C.G.

    1991-07-30

    This patent describes a heating apparatus. It comprises a housing, means for introducing water to a plurality of water conduits of the housing, a fireplace compartment disposed within the housing, the fireplace compartment being provided with a burner, a fin coil member disposed in the upper portion of the housing and communicating with the room environment for heat emitting, the fin coil member containing a serpentine configured fin coils disposed therein for absorbing heat from the water disposed in the water conduits, a heat chamber containing the water conduits, the heat chamber connected at one end to the fireplace compartment and at the other end to a chimney disposed at the middle of the the fireplace compartment for circulating hot combustion gases therethrough and for heating the water disposed in the water conduits, the combustion gases being vented from the chimney, and at least four turbo fans communicating with the heat chamber for blowing air across the fin coil member so as to heat the air and discharge it to the room environment, and reduce noise pollution of the heating apparatus.

  12. Automatic transmission control method

    SciTech Connect

    Hasegawa, H.; Ishiguro, T.

    1989-07-04

    This patent describes a method of controlling an automatic transmission of an automotive vehicle. The transmission has a gear train which includes a brake for establishing a first lowest speed of the transmission, the brake acting directly on a ring gear which meshes with a pinion, the pinion meshing with a sun gear in a planetary gear train, the ring gear connected with an output member, the sun gear being engageable and disengageable with an input member of the transmission by means of a clutch. The method comprises the steps of: detecting that a shift position of the automatic transmission has been shifted to a neutral range; thereafter introducing hydraulic pressure to the brake if present vehicle velocity is below a predetermined value, whereby the brake is engaged to establish the first lowest speed; and exhausting hydraulic pressure from the brake if present vehicle velocity is higher than a predetermined value, whereby the brake is disengaged.

  13. Van der Waals Force Assisted Heat Transfer

    NASA Astrophysics Data System (ADS)

    Sasihithlu, K.; Pendry, J. B.; Craster, R. V.

    2017-02-01

    Phonons (collective atomic vibrations in solids) are more effective in transporting heat than photons. This is the reason why the conduction mode of heat transport in nonmetals (mediated by phonons) is dominant compared to the radiation mode of heat transport (mediated by photons). However, since phonons are unable to traverse a vacuum gap (unlike photons), it is commonly believed that two bodies separated by a gap cannot exchange heat via phonons. Recently, a mechanism was proposed [J. B. Pendry, K. Sasihithlu, and R. V. Craster, Phys. Rev. B 94, 075414 (2016)] by which phonons can transport heat across a vacuum gap - through the Van der Waals interaction between two bodies with gap less than the wavelength of light. Such heat transfer mechanisms are highly relevant for heating (and cooling) of nanostructures; the heating of the flying heads in magnetic storage disks is a case in point. Here, the theoretical derivation for modelling phonon transmission is revisited and extended to the case of two bodies made of different materials separated by a vacuum gap. Magnitudes of phonon transmission, and hence the heat transfer, for commonly used materials in the micro- and nano-electromechanical industry are calculated and compared with the calculation of conduction heat transfer through air for small gaps as well as the heat transfer calculation due to photon exchange.

  14. Heat Problems.

    ERIC Educational Resources Information Center

    Connors, G. Patrick

    Heat problems and heat cramps related to jogging can be caused by fluid imbalances, medications, dietary insufficiency, vomiting or diarrhea, among other factors. If the condition keeps reoccurring, the advice of a physician should be sought. Some preventive measures that can be taken include: (1) running during the cooler hours of the day; (2)…

  15. Heat Problems.

    ERIC Educational Resources Information Center

    Connors, G. Patrick

    Heat problems and heat cramps related to jogging can be caused by fluid imbalances, medications, dietary insufficiency, vomiting or diarrhea, among other factors. If the condition keeps reoccurring, the advice of a physician should be sought. Some preventive measures that can be taken include: (1) running during the cooler hours of the day; (2)…

  16. Heat transfer in microwave heating

    NASA Astrophysics Data System (ADS)

    Peng, Zhiwei

    Heat transfer is considered as one of the most critical issues for design and implement of large-scale microwave heating systems, in which improvement of the microwave absorption of materials and suppression of uneven temperature distribution are the two main objectives. The present work focuses on the analysis of heat transfer in microwave heating for achieving highly efficient microwave assisted steelmaking through the investigations on the following aspects: (1) characterization of microwave dissipation using the derived equations, (2) quantification of magnetic loss, (3) determination of microwave absorption properties of materials, (4) modeling of microwave propagation, (5) simulation of heat transfer, and (6) improvement of microwave absorption and heating uniformity. Microwave heating is attributed to the heat generation in materials, which depends on the microwave dissipation. To theoretically characterize microwave heating, simplified equations for determining the transverse electromagnetic mode (TEM) power penetration depth, microwave field attenuation length, and half-power depth of microwaves in materials having both magnetic and dielectric responses were derived. It was followed by developing a simplified equation for quantifying magnetic loss in materials under microwave irradiation to demonstrate the importance of magnetic loss in microwave heating. The permittivity and permeability measurements of various materials, namely, hematite, magnetite concentrate, wüstite, and coal were performed. Microwave loss calculations for these materials were carried out. It is suggested that magnetic loss can play a major role in the heating of magnetic dielectrics. Microwave propagation in various media was predicted using the finite-difference time-domain method. For lossy magnetic dielectrics, the dissipation of microwaves in the medium is ascribed to the decay of both electric and magnetic fields. The heat transfer process in microwave heating of magnetite

  17. Tractor Transmissions. A Teaching Reference.

    ERIC Educational Resources Information Center

    American Association for Agricultural Engineering and Vocational Agriculture, Athens, GA.

    The manual was developed as a reference for teaching students about transmissions in farm tractors. The manual is divided into five sections: (1) transmission history, (2) gears and bearings in transmission, (3) sliding-gear transmissions, (4) planetary gearing, and (5) glossary. The working principles of the sliding-gear transmission, the most…

  18. Hybrid geared traction transmissions

    NASA Technical Reports Server (NTRS)

    Nasvytis, A. L.; White, G.

    1983-01-01

    The basic configuration of geared traction drives, geometric and structural factors to be considered in their construction, and current work on hybrid helicopter transmissions rated at 500 and 3000 hp are discussed.

  19. Down hole transmission system

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy

    2007-07-24

    A transmission system in a downhole component comprises a data transmission element in both ends of the downhole component. Each data transmission element houses an electrically conducting coil in a MCEI circular trough. The electrically conducting coil comprises at least two generally fractional loops. In the preferred embodiment, the transmission elements are connected by an electrical conductor. Preferably, the electrical conductor is a coaxial cable. Preferably, the MCEI trough comprises ferrite. In the preferred embodiment, the fractional loops are connected by a connecting cable. In one aspect of the present invention, the connecting cable is a pair of twisted wires. In one embodiment the connecting cable is a shielded pair of twisted wires. In another aspect of the present invention, the connecting cable is a coaxial cable. The connecting cable may be disposed outside of the MCEI circular trough.

  20. Downhole transmission system

    DOEpatents

    Hall, David R [Provo, UT; Fox, Joe [Spanish Fork, UT

    2008-01-15

    A transmission system in a downhole component comprises a data transmission element in both ends of the downhole component. Each data transmission element houses an electrically conducting coil in a MCEI circular trough. An electrical conductor connects both the transmission elements. The electrical conductor comprises at least three electrically conductive elements insulated from each other. In the preferred embodiment the electrical conductor comprises an electrically conducting outer shield, an electrically conducting inner shield and an electrical conducting core. In some embodiments of the present invention, the electrical conductor comprises an electrically insulating jacket. In other embodiments, the electrical conductor comprises a pair of twisted wires. In some embodiments, the electrical conductor comprises semi-conductive material.

  1. Pregnancy & perinatal transmission update.

    PubMed

    Denison, R

    1998-09-01

    According to a June 1998 report from UNAIDS, the majority of children infected with HIV acquired it from their mothers during or near birth. One way to prevent perinatal transmission of HIV is to increase prevention efforts for women. Other ways to prevent perinatal transmission include using AZT treatment, avoiding breastfeeding, and choosing a C-section delivery instead of a vaginal delivery. One important study, called the Thai study, promoted a shorter course of AZT therapy that was less expensive, more accessible, and still prevented transmission in many cases. Several reasons are cited for why some women continue breastfeeding, despite the increased risk of transmitting HIV to their babies. An important factor in preventing perinatal transmission is the overall health of the mother, and her ability to maintain her health and treatment regimen while caring for a newborn.

  2. Multiplex television transmission system

    NASA Technical Reports Server (NTRS)

    Reed, W. R.

    1967-01-01

    Time-multiplexing system enables several cameras to share a single commercial television transmission channel. This system is useful in industries for visually monitoring several operating areas or instrument panels from a remote location.

  3. Continuously Variable Transmission

    NASA Technical Reports Server (NTRS)

    Grana, D. C.

    1985-01-01

    Chain slides along two cones, in novel transmission concept. Transmission includes chain drive between two splined shafts. Chain sprockets follow surfaces of two cones. As one chain sprocket moves toward smaller diameter other chain sprocket moves toward larger diameter, thereby changing "gear" ratio. Movement initiated by tension applied to chain by planetary gear mechanism. Device positive, simple, and efficient over wide range of speed ratios.

  4. Datacast: The transmission system

    NASA Astrophysics Data System (ADS)

    Chambers, J. P.

    1988-03-01

    The BBC Datacast service allows one-way transmission of general data services for public service data broadcasting or for commercial purposes using the existing teletext system as the carrier. Such uses were anticipated when the 1976 UK teletext specification was written, so Datacast can co-exist with the normal teletext service (Ceefax) without problems. This Report provides a detailed specification of the Datacast transmission standard.

  5. Heat collector

    DOEpatents

    Merrigan, Michael A.

    1984-01-01

    A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

  6. Heat collector

    DOEpatents

    Merrigan, M.A.

    1981-06-29

    A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

  7. 77 FR 6554 - Zephyr Power Transmission, LLC; Pathfinder Power Transmission, LLC; Duke-American Transmission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-08

    ... Energy Regulatory Commission Zephyr Power Transmission, LLC; Pathfinder Power Transmission, LLC; Duke-American Transmission Company, LLC; Notice of Petition for Declaratory Order Take notice that on January 30... (Commission), 18 CFR 381.302, Zephyr Power Transmission, LLC (Zephyr), Pathfinder Power Transmission, LLC...

  8. Multistate differential transmission

    SciTech Connect

    Whalen, B.

    1987-09-01

    A multistate transmission is described having an input shaft and an output shaft comprising: a. planetary gear train means having a ring gear, planetary gears with planetary gear carrier, and a sun gear, the planetary gear train means connected to the output shaft; b. first bypass means connecting the input shaft to the planetary gear train means; c. differential transmission means for receiving its input from the input shaft and having means to adjust the torque and speed output infinitely variable over its range of operation for each state of the transmission; d. power return means for receiving the output of the differential transmission means; e. means including clutch operated speed reversing means for interconnecting the sun gear in the planetary gear train means with the power return means; f. the power return means including a first gear to receive the output of the differential transmission means; g. first multispeed transmission means connecting the means for supporting the carrier shaft to the first bypass means.

  9. National transmission grid study

    SciTech Connect

    Abraham, Spencer

    2003-05-31

    The National Energy Policy Plan directed the U.S. Department of Energy (DOE) to conduct a study to examine the benefits of establishing a national electricity transmission grid and to identify transmission bottlenecks and measures to address them. DOE began by conducting an independent analysis of U.S. electricity markets and identifying transmission system bottlenecks using DOE’s Policy Office Electricity Modeling System (POEMS). DOE’s analysis, presented in Section 2, confirms the central role of the nation’s transmission system in lowering costs to consumers through increased trade. More importantly, DOE’s analysis also confirms the results of previous studies, which show that transmission bottlenecks and related transmission system market practices are adding hundreds of millions of dollars to consumers’ electricity bills each year. A more detailed technical overview of the use of POEMS is provided in Appendix A. DOE led an extensive, open, public input process and heard a wide range of comments and recommendations that have all been considered.1 More than 150 participants registered for three public workshops held in Detroit, MI (September 24, 2001); Atlanta, GA (September 26, 2001); and Phoenix, AZ (September 28, 2001).

  10. Lubricant Effects on Efficiency of a Helicopter Transmission

    NASA Technical Reports Server (NTRS)

    Mitchell, A. M.; Coy, J. J.

    1982-01-01

    Eleven different lubricants were used in efficiency tests conducted on the OH-58A helicopter main transmission using the NASA Lewis Research Center's 500 hp torque regenerative helicopter transmission test stand. Tests were run at oil-in temperatures of 355 K and 372 K. The efficiency was calculated from a heat balance on the water running through an oil to water heat exchanger which the transmission was heavily insulated. Results show an efficiency range from 98.3% to 98.8% which is a 50% variation relative to the losses associated with the maximum efficiency measured. For a given lubricant, the efficiency increased as temperature increased and viscosity decreased. There were two exceptions which could not be explained. Between lubricants, efficiency was not correlated with viscosity. There were relatively large variations in efficiency with the different lubricants whose viscosity generally fell in the 5 to 7 centistoke range. The lubricants had no significant effect on the vibration signature of the transmission.

  11. Corrosive resistant heat exchanger

    DOEpatents

    Richlen, Scott L.

    1989-01-01

    A corrosive and errosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is conveyed through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium.

  12. Resistance heating elements with specific heating profiles

    NASA Technical Reports Server (NTRS)

    Hirschberg, M. H.

    1976-01-01

    Bundled, interrupted, resistance heating elements provide specific heating profiles. Design allows for easily tailored lengths and locations of "hot sections" and larger surface areas for heat radiation.

  13. HEAT EXCHANGER

    DOEpatents

    Fox, T.H. III; Richey, T. Jr.; Winders, G.R.

    1962-10-23

    A heat exchanger is designed for use in the transfer of heat between a radioactive fiuid and a non-radioactive fiuid. The exchanger employs a removable section containing the non-hazardous fluid extending into the section designed to contain the radioactive fluid. The removable section is provided with a construction to cancel out thermal stresses. The stationary section is pressurized to prevent leakage of the radioactive fiuid and to maintain a safe, desirable level for this fiuid. (AEC)

  14. Diaphragm Stirling engine heat-actuated heat pump development

    NASA Astrophysics Data System (ADS)

    Ackermann, R. A.; Swenson, P.

    A power module, consisting of a free displacer, resonant Stirling engine, hydraulic transmission, and resonant Rankine refrigerant (F-22) compressor, embodies several innovative concepts in free-piston Stirling engine heat pump design that will advance the state of the art of this technology. Progress is reported in three areas of the program. A compressor/engine matching analysis and a stability analysis show that the power module, which is representative of a two-degree-of-freedom resonant system, can operate stably over the full range of heat pump conditions. A compressor design evolved that has met criteria for performance and cost. Tests employing a hydraulic simulator test rig show that the transmission losses are less than had been predicted, and that properly designed and fabricated diaphragms can attain long life.

  15. Modular Heat Exchanger With Integral Heat Pipe

    NASA Technical Reports Server (NTRS)

    Schreiber, Jeffrey G.

    1992-01-01

    Modular heat exchanger with integral heat pipe transports heat from source to Stirling engine. Alternative to heat exchangers depending on integrities of thousands of brazed joints, contains only 40 brazed tubes.

  16. Infinitely variable steering transmission

    SciTech Connect

    Reed, B.O.

    1989-04-04

    A steering transmission is described comprising: first and second drive units each driven at a substantially constant speed for producing respective first and second unidirectional, continuous outputs infinitely variable between a minimum speed and a maximum speed; a first output planetary gear drivingly connected to a first transmission output; a second output planetary gear set drivingly connected to a second transmission output; an input gear set; means interconnecting the first and second output planetary gear sets; means connecting the first drive unit to the first output planetary gear set; means applying the second drive unit output to the second output planetary gear set; means applying a substantially constant speed input to the input gear set; means for selectively conditioning the input gear set to drive the one output planetary gear set at a speed having a first predetermined fixed ratio to the constant speed input, whereby to operate the transmission in one speed range; and means for selectively applying the first drive unit output to second output planetary gear set, whereby to operate the transmission in another speed range different from the one speed range.

  17. Torque feedback transmission

    SciTech Connect

    Whalen, B.L.

    1987-01-20

    This patent describes an infinitely variable transmission of inline configuration for interconnecting a primer mover with a load for clutch free operation in a range of speed including hydraulic neutral comprising: a. planetary gear train means having a ring gear, planetary gears supported by a planetary gear carrier, and a sun gear, the sun gear being connected mechanically to the load, output shaft means for joining the sun gear to the load; b. variable torque feedback means comprising (i) a variable displacement hydraulic motor whose rotor shaft is in line with the output shaft means and drivingly connected to the prime mover and the planetary gear carrier during the full range of operation of the transmission, and (ii) a fixed displacement hydraulic pump connected hydraulically to the motor, the rotor shaft of the pump being connected mechanically to the ring gear and being axially displaced from the output shaft means; c. means for adjusting the displacement volume within the hydraulic motor for controlling the torque feedback in the transmission to provide infinitely variable coupling between the prime mover and the load over the full range of the transmission including hydraulic neutral; d. a speed reducer between the primer mover and the motor rotor shaft and a speed multiplier between the sun gear and the load; and e. mechanical transmission assembly means between the speed multiplier and the load in line with the motor rotor shaft and the output shaft means for providing selection of drive, reverse, park, and neutral.

  18. Contrast Transmission In Rain

    NASA Astrophysics Data System (ADS)

    Winchester, L. W., Jr.; Gimmestad, G. G.; Jackovich, J. E.

    1983-09-01

    While the propagation of visible and infrared radiation in adverse weather has been studied by many investigators, the effect of rain on contrast transmission or visual range have received little attention. A theoretical and experimental program examining contrast transmission in adverse weather will be described in this paper. Measurements of contrast transmission were made using bar targets consisting of parallel flourescent light bulbs. The bulb spacing is four times the bulb diameter. Data is obtained by photographing the target from a distance of two hundred meters using a camera fitted with an eight-hundred millimeter lens under both clear and obscured conditions. The negatives are then analyzed using a microdensitometer and contrast is defined by C = (I MAX - i MAX + i MIN)-1 where I-MAX and I-MIN are the intensity maximum and minimum, respectively. In addition to contrast measurements, simultaneous measurements of atmospheric transmission, snow particle phase function, and all relevant weather parameters are made. A computer model, based on scattering theory, has been developed for predicting contrast transmission. The model computes zero, first and second order scattering contributions in a three-dimensional atmosphere using phase function computations based on Mie theory.

  19. Chromospheric Heating

    NASA Astrophysics Data System (ADS)

    Musielak, Z. E.

    2002-05-01

    It is now well-established that the Sun and all other late-type stars show chromospheric activity, which is typically identified with the presence of emission in the cores of Ca II and Mg II spectral lines. This activity varies significantly for a given spectral type and a star is more active when a larger portion of its surface is covered by magnetic fields. For stars of very low activity, a minimum core emission flux ("basal flux") has been observed. To explain the required heating and the observed range of activity, two classes of heating mechanisms have been considered: (1) dissipation of acoustic and magnetic waves generated in stellar convection zones; and (2) dissipation of currents generated by photospheric motions of surface magnetic fields. I will review both classes of heating mechanisms and discuss recent results which demonstrate that theoretical models of stellar chromospheres based on the wave heating (1) can explain the "basal flux" and the observed Ca II emission in most stars but cannot account for the observed Mg II emission in active stars. I will also present theoretical arguments which imply that the base of stellar chromospheres is heated by acoustic waves, the heating of the middle and upper chromospheric layers is dominated by magnetic waves associated with magnetic flux tubes, and that other non-wave (2) heating mechanisms are required to explain the structure of the highest layers of stellar chromospheres in active stars. This work was supported by NSF under grant ATM-0087184, NATO under grant CRG-910058 and The Alexander von Humboldt Foundation.

  20. Magnetar Heating

    NASA Astrophysics Data System (ADS)

    Beloborodov, Andrei M.; Li, Xinyu

    2016-12-01

    We examine four candidate mechanisms that could explain the high surface temperatures of magnetars. (1) Heat flux from the liquid core heated by ambipolar diffusion. It could sustain the observed surface luminosity {{\\mathscr{L}}}s≈ {10}35 erg s-1 if core heating offsets neutrino cooling at a temperature {T}{core}\\gt 6× {10}8 K. This scenario is viable if the core magnetic field exceeds 1016 G and the heat-blanketing envelope of the magnetar has a light-element composition. However, we find that the lifetime of such a hot core should be shorter than the typical observed lifetime of magnetars. (2) Mechanical dissipation in the solid crust. This heating can be quasi-steady, powered by gradual (or frequent) crustal yielding to magnetic stresses. We show that it obeys a strong upper limit. As long as the crustal stresses are fostered by the field evolution in the core or Hall drift in the crust, mechanical heating is insufficient to sustain persistent {{\\mathscr{L}}}s≈ {10}35 erg s-1. The surface luminosity is increased in an alternative scenario of mechanical deformations triggered by external magnetospheric flares. (3) Ohmic dissipation in the crust, in volume or current sheets. This mechanism is inefficient because of the high conductivity of the crust. Only extreme magnetic configurations with crustal fields B\\gt {10}16 G varying on a 100 meter scale could provide {{\\mathscr{L}}}s≈ {10}35 erg s-1. (4) Bombardment of the stellar surface by particles accelerated in the magnetosphere. This mechanism produces hot spots on magnetars. Observations of transient magnetars show evidence of external heating.

  1. Small passenger car transmission test: Mercury Lynx ATX transmission

    NASA Technical Reports Server (NTRS)

    Bujold, M. P.

    1981-01-01

    The testing of a Mercury Lynx automatic transmission is reported. The transmission was tested in accordance with a passenger car automatic transmission test code (SAE J65lb) which required drive performance, coast performance, and no load test conditions. Under these conditions, the transmission attained maximum efficiencies in the mid-ninety percent range both for drive performance test and coast performance tests. The torque, speed, and efficiency curves are presented, which provide the complete performance characteristics for the Mercury Lynx automatic transmission.

  2. Small passenger car transmission test: Dodge Omni A-404 transmission

    NASA Technical Reports Server (NTRS)

    Bujold, M. P.

    1980-01-01

    The small passenger car transmission test was initiated to supply electric vehicle manufacturers with technical information regarding the performance of commercially available transmissions. This transmission was tested in accordance with a passenger car automatic transmission test code (SAE J65lb) which required drive performance, coast performance, and no load test conditions. Under these test conditions, the transmission attained maximum efficiencies in the mid eighty percent range for both drive performance test and coast performance tests.

  3. Disease transmission in horses.

    PubMed

    Samper, Juan C; Tibary, Ahmed

    2006-08-01

    Bacterial, viral and protozoal infections may cause severe reproductive losses. The present paper reviews the risk factors, clinical signs and preventive measures for the most important venereal or potential sexually transmitted diseases in horses. The stallion and use of semen for artificial insemination represent major risk factors for the transmission of bacterial contaminants of the penis, including Streptococcus equi subspecies zooepidemicus, Pseudomonas aeruginosa and Klebsiella pneumoniae, known to cause endometritis and infertility in the mare. The role of the stallion in disease transmission is also due to the non-clinical manifestation of diseases such as contagious equine metritis and equine viral arteritis. Dourine has been eradicated from many countries, but continues to be a problem in other areas of the globe. Strategies for the prevention of introduction and transmission of diseases in breeding operation are discussed.

  4. Aerosol Transmission of Filoviruses.

    PubMed

    Mekibib, Berhanu; Ariën, Kevin K

    2016-05-23

    Filoviruses have become a worldwide public health concern because of their potential for introductions into non-endemic countries through international travel and the international transport of infected animals or animal products. Since it was first identified in 1976, in the Democratic Republic of Congo (formerly Zaire) and Sudan, the 2013-2015 western African Ebola virus disease (EVD) outbreak is the largest, both by number of cases and geographical extension, and deadliest, recorded so far in medical history. The source of ebolaviruses for human index case(s) in most outbreaks is presumptively associated with handling of bush meat or contact with fruit bats. Transmission among humans occurs easily when a person comes in contact with contaminated body fluids of patients, but our understanding of other transmission routes is still fragmentary. This review deals with the controversial issue of aerosol transmission of filoviruses.

  5. Automotive transmission linkage system

    SciTech Connect

    Yen, F.Y.; Ardayfio, D.D.

    1990-10-02

    This patent describes a system for converting a manual multi-speed transmission to operate as an automatic-manual transmission, the system being disposed within a vehicle, the transmission having a conventional gearshift lever and a clutch pedal. It comprises: a gearshift position selection panel, the panel being located apart from the gearshift lever, the panel enabling a driver to select the desired gear position of the gearshift lever by manipulating the panel without the necessity of the driver handling the gearshift lever; a controller which transforms the gearshift selection of the driver to an output signal, the signal corresponding to the gearshift position selected by the driver; and actuating means for mechanically repositioning the gearshift lever automatically in accordance with the output signal.

  6. Aerosol Transmission of Filoviruses

    PubMed Central

    Mekibib, Berhanu; Ariën, Kevin K.

    2016-01-01

    Filoviruses have become a worldwide public health concern because of their potential for introductions into non-endemic countries through international travel and the international transport of infected animals or animal products. Since it was first identified in 1976, in the Democratic Republic of Congo (formerly Zaire) and Sudan, the 2013–2015 western African Ebola virus disease (EVD) outbreak is the largest, both by number of cases and geographical extension, and deadliest, recorded so far in medical history. The source of ebolaviruses for human index case(s) in most outbreaks is presumptively associated with handling of bush meat or contact with fruit bats. Transmission among humans occurs easily when a person comes in contact with contaminated body fluids of patients, but our understanding of other transmission routes is still fragmentary. This review deals with the controversial issue of aerosol transmission of filoviruses. PMID:27223296

  7. Sheath energy transmission in a collisional plasma with collisionless sheath

    SciTech Connect

    Tang, Xian-Zhu Guo, Zehua

    2015-10-15

    Sheath energy transmission governs the plasma energy exhaust onto a material surface. The ion channel is dominated by convection, but the electron channel has a significant thermal conduction component, which is dominated by the Knudsen layer effect in the presence of an absorbing wall. First-principle kinetic simulations reveal a robustly supersonic sheath entry flow. The ion sheath energy transmission and the sheath potential are accurately predicted by a sheath model of truncated bi-Maxwellian electron distribution. The electron energy transmission is further enhanced by a parallel heat flux of the perpendicular degrees of freedom.

  8. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Bobs Candies, Inc. produces some 24 million pounds of candy a year, much of it 'Christmas candy.' To meet Christmas demand, it must produce year-round. Thousands of cases of candy must be stored a good part of the year in two huge warehouses. The candy is very sensitive to temperature. The warehouses must be maintained at temperatures of 78-80 degrees Fahrenheit with relative humidities of 38- 42 percent. Such precise climate control of enormous buildings can be very expensive. In 1985, energy costs for the single warehouse ran to more than $57,000 for the year. NASA and the Florida Solar Energy Center (FSEC) were adapting heat pipe technology to control humidity in building environments. The heat pipes handle the jobs of precooling and reheating without using energy. The company contacted a FSEC systems engineer and from that contact eventually emerged a cooperative test project to install a heat pipe system at Bobs' warehouses, operate it for a period of time to determine accurately the cost benefits, and gather data applicable to development of future heat pipe systems. Installation was completed in mid-1987 and data collection is still in progress. In 1989, total energy cost for two warehouses, with the heat pipes complementing the air conditioning system was $28,706, and that figures out to a cost reduction.

  9. Heat Pipes

    NASA Astrophysics Data System (ADS)

    1990-01-01

    Bobs Candies, Inc. produces some 24 million pounds of candy a year, much of it 'Christmas candy.' To meet Christmas demand, it must produce year-round. Thousands of cases of candy must be stored a good part of the year in two huge warehouses. The candy is very sensitive to temperature. The warehouses must be maintained at temperatures of 78-80 degrees Fahrenheit with relative humidities of 38- 42 percent. Such precise climate control of enormous buildings can be very expensive. In 1985, energy costs for the single warehouse ran to more than 57,000 for the year. NASA and the Florida Solar Energy Center (FSEC) were adapting heat pipe technology to control humidity in building environments. The heat pipes handle the jobs of precooling and reheating without using energy. The company contacted a FSEC systems engineer and from that contact eventually emerged a cooperative test project to install a heat pipe system at Bobs' warehouses, operate it for a period of time to determine accurately the cost benefits, and gather data applicable to development of future heat pipe systems. Installation was completed in mid-1987 and data collection is still in progress. In 1989, total energy cost for two warehouses, with the heat pipes complementing the air conditioning system was 28,706, and that figures out to a cost reduction.

  10. Transmission line capital costs

    SciTech Connect

    Hughes, K.R.; Brown, D.R.

    1995-05-01

    The displacement or deferral of conventional AC transmission line installation is a key benefit associated with several technologies being developed with the support of the U.S. Department of Energy`s Office of Energy Management (OEM). Previous benefits assessments conducted within OEM have been based on significantly different assumptions for the average cost per mile of AC transmission line. In response to this uncertainty, an investigation of transmission line capital cost data was initiated. The objective of this study was to develop a database for preparing preliminary estimates of transmission line costs. An extensive search of potential data sources identified databases maintained by the Bonneville Power Administration (BPA) and the Western Area Power Administration (WAPA) as superior sources of transmission line cost data. The BPA and WAPA data were adjusted to a common basis and combined together. The composite database covers voltage levels from 13.8 to 765 W, with cost estimates for a given voltage level varying depending on conductor size, tower material type, tower frame type, and number of circuits. Reported transmission line costs vary significantly, even for a given voltage level. This can usually be explained by variation in the design factors noted above and variation in environmental and land (right-of-way) costs, which are extremely site-specific. Cost estimates prepared from the composite database were compared to cost data collected by the Federal Energy Regulatory Commission (FERC) for investor-owned utilities from across the United States. The comparison was hampered because the only design specifications included with the FERC data were voltage level and line length. Working within this limitation, the FERC data were not found to differ significantly from the composite database. Therefore, the composite database was judged to be a reasonable proxy for estimating national average costs.

  11. Heterosexual transmission of HIV.

    PubMed

    Johnson, A M; Laga, M

    1988-01-01

    Recent developments concerning heterosexual transmission of HIV (review of 1988 literature only) suggest improved understanding of the pattern of spread and role of risk behaviors and biological cofactors in its transmission. 3 distinct patterns if HIV infection are known: heterosexual spread in sub-Saharan Africa and the Caribbean, spread primarily among homosexuals and injecting drug users in Europe, North American and much of Latin America and Australia, and both homosexual and heterosexual transmission in Asia, the Pacific, the Middle East and Eastern Europe, where prevalence is low. In Africa an estimated 80% of cases are acquired heterosexually. Important risk factors are number of sex partners, sex with prostitutes, being a prostitute, being a sex partner of an infected person, and having a history of other sexually transmitted diseases. Prevalence rates have risen rapidly in Zaire and Kenya. In Africa, acquisition of HIV is related to sexual activity only. In contrast, in the U.S., heterosexual cases make up only 4% of all cases, and in Europe only 6%. Data on types of sexual transmission of HIV are mounting, in aggregate suggestive of a marked heterogeneity in infectivity and possibly susceptibility between individuals. Among couples where the man is positive, in some places individuals appear to be highly infective, notably those from Kinshasa, Zaire and Haiti, while other series of discordant couples the receptive partner remained seronegative for several years. Transmission from women to men appears to be less efficient than from men to women, as has been observed with other STDs such as gonorrhea. Biological cofactors implicated in enhanced HIV transmission appear to be advanced CDC Stage IV AIDS disease, with low T-helper lymphocyte counts and high antigenemia; concomitant STDS, especially those with genital ulceration; lack of circumcision; oral contraceptive use; practice of anal intercourse; inconsistent or no use of condoms. Theoretical models for

  12. Advanced rotorcraft transmission program

    NASA Technical Reports Server (NTRS)

    Bill, Robert C.

    1990-01-01

    The Advanced Rotorcraft Transmission (ART) program is an Army-funded, joint Army/NASA program to develop and demonstrate lightweight, quiet, durable drivetrain systems for next generation rotorcraft. ART addresses the drivetrain requirements of two distinct next generation aircraft classes: Future Air Attack Vehicle, a 10,000 to 20,000 lb. aircraft capable of undertaking tactical support and air-to-air missions; and Advanced Cargo Aircraft, a 60,000 to 80,000 lb. aircraft capable of heavy life field support operations. Both tiltrotor and more conventional helicopter configurations are included in the ART program. Specific objectives of ART include reduction of drivetrain weight by 25 percent compared to baseline state-of-the-art drive systems configured and sized for the next generation aircraft, reduction of noise level at the transmission source by 10 dB relative to a suitably sized and configured baseline, and attainment of at least a 5000 hr mean-time-between-removal. The technical approach for achieving the ART goals includes application of the latest available component, material, and lubrication technology to advanced concept drivetrains that utilize new ideas in gear configuration, transmission layout, and airframe/drivetrain integration. To date, candidate drivetrain systems were carried to a conceptual design stage, and tradeoff studies were conducted resulting in selection of an ART transmission configuration for each of the four contractors. The final selection was based on comparative weight, noise, and reliability studies. A description of each of the selected ART designs is included. Preliminary design of each of the four selected ART transmission was completed, as have mission impact studies wherein comparisons of aircraft mission performance and life cycle costs are undertaken for the next generation aircraft with ART and with the baseline transmission.

  13. Licklider Transmission Protocol Implementation

    NASA Technical Reports Server (NTRS)

    Burleigh, Scott C.; Krupiarz, Chris

    2011-01-01

    This software is an implementation of the Licklider Transmission Protocol (LTP), a communications protocol intended to support the Bundle Protocol in Delay-Tolerant Network (DTN) operations. LTP is designed to provide retransmission-based reliability over links characterized by extremely long message round-trip times and/or frequent interruptions in connectivity. Communication in interplanetary space is the most prominent example of this sort of environment, and LTP is principally aimed at supporting long-haul reliable transmission over deep-space RF links. Like any reliable transport service employing ARQ (Automatic Repeat re-Quests), LTP is stateful. In order to assure the reception of a block of data it has sent, LTP must retain for possible retransmission all portions of that block which might not have been received yet. In order to do so, it must keep track of which portions of the block are known to have been received so far, and which are not, together with any additional information needed for purposes of retransmitting part, or all, of the block. Long round-trip times mean substantial delay between the transmission of a block of data and the reception of an acknowledgement from the block s destination, signaling arrival of the block. If LTP postponed transmission of additional blocks of data until it received acknowledgement of the arrival of all prior blocks, valuable opportunities to use what little deep space transmission bandwidth is available would be forever lost. For this reason, LTP is based in part on a notion of massive state retention. Any number of requested transmission conversations (sessions) may be concurrently in flight at various displacements along the link between two LTP engines, and the LTP engines must necessarily retain transmission status and retransmission resources for all of them. Moreover, if any of the data of a given block are lost en route, it will be necessary to retain the state of that transmission during an additional

  14. Printed circuit dispersive transmission line

    DOEpatents

    Ikezi, Hiroyuki; Lin-Liu, Yuh-Ren; DeGrassie, John S.

    1991-01-01

    A printed circuit dispersive transmission line structure is disclosed comprising an insulator, a ground plane formed on one surface of the insulator, a first transmission line formed on a second surface of the insulator, and a second transmission line also formed on the second surface of the insulator and of longer length than the first transmission line and periodically intersecting the first transmission line. In a preferred embodiment, the transmission line structure exhibits highly dispersive characteristics by designing the length of one of the transmission line between two adjacent periodic intersections to be longer than the other.

  15. Printed circuit dispersive transmission line

    DOEpatents

    Ikezi, H.; Lin-Liu, Y.R.; DeGrassie, J.S.

    1991-08-27

    A printed circuit dispersive transmission line structure is disclosed comprising an insulator, a ground plane formed on one surface of the insulator, a first transmission line formed on a second surface of the insulator, and a second transmission line also formed on the second surface of the insulator and of longer length than the first transmission line and periodically intersecting the first transmission line. In a preferred embodiment, the transmission line structure exhibits highly dispersive characteristics by designing the length of one of the transmission line between two adjacent periodic intersections to be longer than the other. 5 figures.

  16. HEAT GENERATION

    DOEpatents

    Imhoff, D.H.; Harker, W.H.

    1963-12-01

    Heat is generated by the utilization of high energy neutrons produced as by nuclear reactions between hydrogen isotopes in a blanket zone containing lithium, a neutron moderator, and uranium and/or thorium effective to achieve multtplicatton of the high energy neutron. The rnultiplied and moderated neutrons produced react further with lithium-6 to produce tritium in the blanket. Thermal neutron fissionable materials are also produced and consumed in situ in the blanket zone. The heat produced by the aggregate of the various nuclear reactions is then withdrawn from the blanket zone to be used or otherwise disposed externally. (AEC)

  17. Chromospheric heating

    NASA Technical Reports Server (NTRS)

    Kalkofen, Wolfgang

    1989-01-01

    The solar chromosphere is identified with the atmosphere inside magnetic flux tubes. Between the temperature minimum and the 7000 K level, the chromosphere in the bright points of the quiet sun is heated by large-amplitude, long-period, compressive waves with periods mainly between 2 and 4 minutes. These waves do not observe the cutoff condition according to which acoustic waves with periods longer than 3 minutes do not propagate vertically in the upper solar photosphere. It is concluded that the long-period waves probably supply all the energy required for the heating of the bright points in the quiet solar chromosphere.

  18. Renewable Heating and Cooling

    EPA Pesticide Factsheets

    Renewable heating and cooling is a set of alternative resources and technologies that can be used in place of conventional heating and cooling technologies for common applications such as water heating, space heating, space cooling and process heat.

  19. Automatic Transmission Vehicle Injuries

    PubMed Central

    Fidler, Malcolm

    1973-01-01

    Four drivers sustained severe injuries when run down by their own automatic cars while adjusting the carburettor or throttle linkages. The transmission had been left in the “Drive” position and the engine was idling. This accident is easily avoidable. PMID:4695693

  20. Transmission planning in China

    SciTech Connect

    Dong, Jun; Zhang, Jing

    2009-07-15

    Though China is well along in restructuring its power markets, it still has some way to travel before economic considerations receive adequate weight in transmission planning decisions. Adoption of more sophisticated tools such as multi-agent modeling will help China continue in its progress in achieving this. (author)

  1. Categories and Music Transmission

    ERIC Educational Resources Information Center

    Gatien, Greg

    2009-01-01

    Lucy Green's (2008) "Music, Informal Learning, and the School: A New Classroom Pedagogy" gives rise to an interesting corollary. Does the manner of music's transmission inform one's understanding of a musical category? While categories of music can be difficult to define according to strict musical characteristics, a better understanding of…

  2. Autonomous data transmission apparatus

    DOEpatents

    Kotlyar, O.M.

    1997-03-25

    A autonomous borehole data transmission apparatus is described for transmitting measurement data from measuring instruments at the downhole end of a drill string by generating pressure pulses utilizing a transducer longitudinally responsive to magnetic field pulses caused by electrical pulses corresponding to the measured downhole parameters. 4 figs.

  3. Facsimile Transmission Standards

    DTIC Science & Technology

    1993-10-01

    transmettre les cartes tactiques et les compte rendu de situation. La presente note technique expose les 6lements nec~ssaires A la transmission de t~l6copies...Group MI machines introduced digital scanning techniques in which the single photoelectric cell was replaced with a Charged Coupled Device (CCD) array

  4. Continuously variable transmission

    SciTech Connect

    Itoh, H.; Okada, M.

    1986-11-25

    This patent describes a continuously variable transmission for transmitting a torque from an engine to a final reduction gear, comprising: an input shaft connected with the engine at one end thereof; a continuously variable transmission means having a driving pulley with a fixed member and a movable member, the movable member being actuated by an hydraulic cylinder to form a V-shaped opening between the fixed member and movable member, a driven pulley with another fixed member and another movable member. The other movable member is similarly actuated by another hydraulic cylinder to form another V-shaped opening between the other fixed member and the other movable member, and a belt member spanning the pulleys provides for a continuously variable transmission ratio; a planetary gear unit including a sun gear, a plurality of pinion gears which mesh with the sun gear and are connected with the driven pulley and a ring gear which meshes with the plurality of pinion gears; and a rotation transmitting means for transmitting rotation of the input shaft to the planetary gear unit. The rotation transmitting means is provided between the input shaft and the planetary gear unit and includes a shaft connected with the sun gear of the planetary gear unit and a first gear connected with the input shaft. The first gear is located between the engine and the continuously variable transmission means.

  5. Laser power transmission

    NASA Technical Reports Server (NTRS)

    Conway, Edmund J.

    1992-01-01

    An overview of previous studies related to laser power transmission is presented. Particular attention is given to the use of solar pumped lasers for space power applications. Three general laser mechanisms are addressed: photodissociation lasing driven by sunlight, photoexcitation lasing driven directly by sunlight, and photoexcitation lasing driven by thermal radiation.

  6. Automatic transmission line monitor

    NASA Technical Reports Server (NTRS)

    Parsons, W. E.; Richards, L. O.

    1971-01-01

    Monitor improves complex network reliability in computer data links and command transmission lines. System evaluates circuit performance against preselected criteria, identifies and stores data indicating out-of-tolerance conditions, conducts closed loop testing, and provides for operation under command of digital computer that determines restoration priorities.

  7. Autonomous data transmission apparatus

    DOEpatents

    Kotlyar, Oleg M.

    1997-01-01

    A autonomous borehole data transmission apparatus for transmitting measurement data from measuring instruments at the downhole end of a drill string by generating pressure pulses utilizing a transducer longitudinally responsive to magnetic field pulses caused by electrical pulses corresponding to the measured downhole parameters.

  8. Categories and Music Transmission

    ERIC Educational Resources Information Center

    Gatien, Greg

    2009-01-01

    Lucy Green's (2008) "Music, Informal Learning, and the School: A New Classroom Pedagogy" gives rise to an interesting corollary. Does the manner of music's transmission inform one's understanding of a musical category? While categories of music can be difficult to define according to strict musical characteristics, a better understanding of…

  9. Dilemmas of Cultural Transmission

    ERIC Educational Resources Information Center

    Kováts-Németh, Mária

    2016-01-01

    The fundamental problem of the 21st century is that in the modern civilization "the transmission of values is not stable." There is nothing, except for the natural sense of justice and some legal traditions, which would exercise selective power on social behavior. At a critical time in 1949 Albert Szent-Györgyi drew the attention to the…

  10. Borehole data transmission apparatus

    DOEpatents

    Kotlyar, O.M.

    1993-03-23

    A borehole data transmission apparatus is described whereby a centrifugal pump impeller(s) is used to provide a turbine stage having substantial pressure characteristics in response to changing rotational speed of a shaft for the pressure pulsing of data from the borehole through the drilling mud to the surface of the earth.

  11. Borehole data transmission apparatus

    DOEpatents

    Kotlyar, Oleg M.

    1993-01-01

    A borehole data transmission apparatus whereby a centrifugal pump impeller(s) is used to provide a turbine stage having substantial pressure characteristics in response to changing rotational speed of a shaft for the pressure pulsing of data from the borehole through the drilling mud to the surface of the earth.

  12. Development of Dynamically Optimized Wireless Transmission System for Wireless Sensor Networks in Highrise Apartment Building Heating Systems / Optimizētas Dinamiskās Bezvadu Sensoru Tīklu Pārraides Risinājuma Izstrāde Daudzstāvu Ēku Apkures Sistēmas Parametru Izgūšanai Un Vadībai

    NASA Astrophysics Data System (ADS)

    Isakovs, V.; Kondratjevs, K.; Kunicina, N.; Freliha, B.; Zabasta, A.

    2015-08-01

    Smart meters will be at the centre of the integrated solutions, including interaction with other networks in the next decade. The developed solution for multi-apartment building ventilation and heating parameter monitoring aims to increase energy efficiency and optimal control of the existing system. Dynamic control of heat and ventilation systems, heat loss detection, calculation and mitigation, and individual heat energy accounting are difficult tasks to accomplish. This article deals with the data transmission system using battery powered ISM band radio transmitters. The temperature measurement sensors with cumulative temperature reading are used as sensor part for this solution. The offered approach to monitoring system is used for overall building and individual apartment monitoring. Data coding and antenna designs are explained for this particular application. Daudzstāvu ēkas, kuras nav sākotnēji plānotas integrācijai ar ēku vadības sistēmām, rada kompleksu problemātisko vidi modernizācijai. Vadu sensoru sistēmu uzstādīšana šādās ēkās kļūst nepraktiska vai pat neiespējama. Šī iemesla dēļ ir nepieciešamas efektīvas bezvadu sensoru sistēmas, kas spētu nodrošināt mērījumu nogādi, ņemot vērā daudzstāvu ēku specifiku. Rakstā tiek piedāvāts bezvadu sensoru tīkla risinājums efektīvai datu pārraidei siltumapgādes sistēmas parametru izgūšanai. Tiek izstrādāta un aprobēta specializētā virziena antena efektīvai radio telegrammu savākšanai no dzīvokļiem, nogādājot mērījumus datu koncentratoros. Ziņojumu telegrammu efektīvai pārraidei tiek piedāvāta datu kodēšanas kumulatīvā metode. Piedāvātais risinājums pielietojams gan jaunām, gan esošām ēkām. Izgūtie dati ir pielietojami siltuma apgādes sistēmas uzraudzībai, regulēšanai, kā arī individuālā siltuma patēriņa tarifikācijai.

  13. District heating/cooling feasibility study for Jamestown, New York

    SciTech Connect

    Oliker, I.; Buffa, W.; Harms, R.; Preston, E.

    1982-12-01

    The report describes the results of a district heating feasibility study for Jamestown, New York based on the use of a power plant located within the city limits. Several options for the extraction of heat from the power plant were developed, with heat balances presented, based on the development of a hot water district heating system. The geography and climate of the area are discussed, as well as the primary potential heat district. The heat load assessment was based on fuel consumption data collected from a sampling of various types of structures and operations. The report presents the methodology in detail, along with block-by-block results including heated floor space, total annual fuel consumed, and peak heat rate demands. A transmission and distribution system was then developed for delivering heat from the power plant to the district heating customers.

  14. Infrared heating

    USDA-ARS?s Scientific Manuscript database

    IR heating was first industrially used in the 1930s for automotive curing applications and rapidly became a widely applied technology in the manufacturing industry. Contrarily, a slower pace in the development of IR technologies for processing foods and agricultural products was observed, due to lim...

  15. Heat exchanger

    DOEpatents

    Wolowodiuk, Walter

    1976-01-06

    A heat exchanger of the straight tube type in which different rates of thermal expansion between the straight tubes and the supply pipes furnishing fluid to those tubes do not result in tube failures. The supply pipes each contain a section which is of helical configuration.

  16. Flash Heating

    NASA Astrophysics Data System (ADS)

    Taylor, G. J.

    2000-03-01

    Meteorites contain millimeter-sized objects called chondrules. They were melted in the solar nebula, the cloud of gas and dust in which the Sun and planets formed. Numerous experiments on rock powders have been done to understand the melting process and the cooling rates chondrules experienced. Most meteorite specialists believe that chondrules formed by flash heating, with almost instantaneous melting, though the length of time they remained molten is uncertain. Can conventional laboratory furnaces heat rock powders rapidly enough to flash melt them? Susan Maharaj and Roger Hewins (Rutgers University, New Brunswick) tested this idea by inserting tiny wires of pure elements (which have precise melting temperatures) into compressed rock powders about 3.5 mm in diameter, and placing the samples into a furnace heated to a range of temperatures. They found that at 1600 C, a sample took only six seconds to reach 1538 C. When placed into a furnace at 1500 C, samples took ten seconds to reach 1495 C. This shows that the flash heating process can be studied in conventional laboratory furnaces.

  17. Examination of heat storage in soil

    NASA Astrophysics Data System (ADS)

    Jaeger, F.; Reichert, J.; Herz, H.

    1981-11-01

    The performance of a heat storage system, based on soil storage by spherical temperature stratification, was assessed and compared to conventional hot water systems for usage in single family houses heated by solar energy. A heat conduction code was used in combination with a simulation model for solar room heating systems in order to evaluate the dependence of storage performance on soil materials, heat transfer parameters, and storage size. Results show that the initially suggested storage scheme should be supplemented with insulation in order to perform somewhat better than hot water storage. A more definite assessment requires further studies on transmission losses, heat capacity enlargement, and mechanical stability and aging properties of insulation materials.

  18. Bayonet heat exchangers in heat-assisted Stirling heat pump

    SciTech Connect

    Yagyu, S.; Fukuyama, Y.; Morikawa, T.; Isshiki, N.; Satoh, I.; Corey, J.; Fellows, C.

    1998-07-01

    The Multi-Temperature Heat Supply System is a research project creating a city energy system with lower environmental load. This system consists of a gas-fueled internal combustion engine and a heat-assisted Stirling heat pump utilizing shaft power and thermal power in a combination of several cylinders. The heat pump is mainly driven by engine shaft power and is partially assisted by thermal power from engine exhaust heat source. Since this heat pump is operated by proportioning the two energy sources to match the characteristics of the driving engine, the system is expected to produce cooling and heating water at high COP. This paper describes heat exchanger development in the project to develop a heat-assisted Stirling heat pump. The heat pump employs the Bayonet type heat exchangers (BHX Type I) for supplying cold and hot water and (BHX Type II) for absorbing exhaust heat from the driving engine. The heat exchanger design concepts are presented and their heat transfer and flow loss characteristics in oscillating gas flow are investigated. The main concern in the BHX Type I is an improvement of gas side heat transfer and the spirally finned tubes were applied to gas side of the heat exchanger. For the BHX Type II, internal heat transfer characteristics are the main concern. Shell-and-tube type heat exchangers are widely used in Stirling machines. However, since brazing is applied to the many tubes for their manufacturing processes, it is very difficult to change flow passages to optimize heat transfer and loss characteristics once they have been made. The challenge was to enhance heat transfer on the gas side to make a highly efficient heat exchanger with fewer parts. It is shown that the Bayonet type heat exchanger can have good performance comparable to conventional heat exchangers.

  19. Laser power transmission.

    NASA Technical Reports Server (NTRS)

    Ahlstrom, H. G.; Christiansen, W. H.; Hertzberg, A.

    1971-01-01

    Description of studies which have led to the design of a conceptual device in which the limitation of transforming heat into coherent radiation can be examined. By exploring the basic thermodynamic relationships controlling the operation of this device, it is concluded that a closed-cycle gasdynamic laser is possible in which all of the shaft energy supplied can be turned into laser radiation. Hence, it is possible in principle to convert heat into coherent radiation with approximately the same efficiency with which heat may be converted into electricity. By modifying the closed-cycle-gasdynamic-laser system, this system can be operated in reverse and the incoming radiation may be used to pump the gas in the loop so that shaft power can be extracted. By carefully controlling the temperature distribution in this machine, laser energy can be converted into useful shaft energy with an efficiency approaching 1 .

  20. [Transmission and prevention].

    PubMed

    Reboulot, B

    1992-01-01

    This work provides an overview of current knowledge of AIDS transmission and attitudes toward prevention in France. Most HIV infections are transmitted sexually. AIDS became established in the homosexual community in California because of mutual infection by members of the community with large numbers of sexual partners. The possibility of heterosexual transmission was not immediately recognized by all observers. Different publications estimate the risk of seroconversion after 1 episode of heterosexual coitus at between 1:100 and 1:1000/ Heterosexual transmission is bidirectional, but male-female transmission appears easier. Factors favoring transmission identified in AFrican studies include multiple partners, sexually transmitted diseases, anal penetration, relations during menstruation, and age. No epidemiologic study has concluded that kissing with mutual salivary contact can lead to infection, but oral-genital sex may pose a risk. As of October 1991, 966 cases of posttransfusion AIDS had been diagnosed in France, and an estimated 6000-9000 HIV seropositive persons were infected through transfusion. 239 AIDS cases were reported in hemophiliacs and others with coagulation disorders. 1200 of 3500 French hemophiliacs receiving transfusions before 1985 are seropositive. The risk of developing AIDS from a transfusions in France is currently estimated at 1/250,000. HIV transmission among drug addicts results from sharing contaminated needles and syringes. The risk of infection for health workers treating those who are HIV positive appears small; only about 30 documented cases have been reported worldwide, including 3 of 10,000 cases in France. The risk that an infected mother will have a seropositive baby is estimated at 25% in France. The number of seropositive women in the world is estimated at over 3 million, with 80% in sub-Saharan Africa. As of October 1991, 16,0000-36,000 seropositive women and 1500 seropositive children were estimated to live in France

  1. Decontamination measures to prevent mechanical transmission of viroids

    USDA-ARS?s Scientific Manuscript database

    With seed-borne and ease in mechanical transmission, an increasing number of viroid outbreaks have been reported in recent years. Such major surge in viroid epidemics is likely enhanced by the intensive ‘hands-on’ activities in greenhouse tomato production. Although viroids are resilient to heat tre...

  2. Advanced transmission studies

    NASA Technical Reports Server (NTRS)

    Coy, John J.; Bill, Robert C.

    1988-01-01

    The NASA Lewis Research Center and the U.S. Army Aviation Systems Command share an interest in advancing the technology for helicopter propulsion systems. In particular, this paper presents highlights from that portion of the program in drive train technology and the related mechanical components. The major goals of the program are to increase the life, reliability, and maintainability; reduce the weight, noise, and vibration; and maintain the relatively high mechanical efficiency of the gear train. The current activity emphasizes noise reduction technology and analytical code development followed by experimental verification. Selected significant advances in technology for transmissions are reviewed, including advanced configurations and new analytical tools. Finally, the plan for future transmission research is presented.

  3. Data transmission networks

    NASA Technical Reports Server (NTRS)

    Alexovich, Robert

    1990-01-01

    A task order was written by the High Resolution, High Frame Rate Video Technology (HHVT) project engineers to investigate data compression techniques that could be applied to the HHVT system, and both existing and planned downlink/uplink capabilities of the Space Shuttle and Space Station Freedom. The following tasks were included: (1) Investigate signal channel availability and determine both the maximum possible data rate and the average data rate; (2) Identify time blocks for HHVT video transmission assuming time sharing and interruptions in the communication links; (3) Determine the bit error rates to be expected; and (4) Define the transmit and receive interfaces. A summary chart of the data transmission capabilities for Tracking and Data Relay Satellite System (TDRSS), the Space Shuttle, Space Station Freedom, Spacelab, and USLab are also presented.

  4. Continuously variable transmission

    SciTech Connect

    Tatara, Y.; Okawa, S.; Matsui, H.; Nakawaki, Y.

    1987-04-28

    A continuously variable transmission means is described for motor vehicles including a driving pulley with a fixed member and a movable member. The movable member is actuated by a hydraulic cylinder to form a V-shaped opening, a driven pulley with another fixed member and another movable member. Another movable member is actuated by another hydraulic cylinder to form another V-shaped opening, and a flexible endless member spans the driving and driven pulleys. The continuously variable transmission means comprises such items as: a first output shaft; a first gear; a second gear; a reverse gear; a second output shaft; a third gear; a jaw clutch mounted; a first one-way clutch; a fourth gear; a hydraulic clutch means; and a second one-way clutch.

  5. Drill string transmission line

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Bradford, Kline; Fox, Joe

    2006-03-28

    A transmission line assembly for transmitting information along a downhole tool comprising a pin end, a box end, and a central bore traveling between the pin end and the box end, is disclosed in one embodiment of the invention as including a protective conduit. A transmission line is routed through the protective conduit. The protective conduit is routed through the central bore and the ends of the protective conduit are routed through channels formed in the pin end and box end of the downhole tool. The protective conduit is elastically forced into a spiral or other non-linear path along the interior surface of the central bore by compressing the protective conduit to a length within the downhole tool shorter than the protective conduit.

  6. Sixteen speed powershift transmission

    SciTech Connect

    McAskill, J.P.

    1991-06-25

    This patent describes a transmission. It includes a transmission housing; a first shaft rotatably mounted in the housing and having a third gear fixed for rotation therewith and fourth and fifth gears rotatably mounted thereto, the fourth and fifth gears meshing with the first and second gears, respectively; first and second clutch means for selectively fixing the fourth and fifth gears, respectively, for rotation with the second shaft; a third shaft rotatably mounted in the housing and having a sixth gear fixed for rotation therewith and seventh and eighth gears rotatably mounted thereto, the seventh and eighth gears meshing with the first and second gears, respectively; third and fourth clutch means for selectively fixing the seventh and eighth gears respectively, for rotation with the third shaft.

  7. Advanced Rotorcraft Transmission Program

    NASA Technical Reports Server (NTRS)

    Bill, Robert C.

    1990-01-01

    The U.S. Army/NASA Advanced Rotorcraft Transmission (ART) program is charged with developing and demonstrating a light, quiet, and durable drivetrain for next-generation rotorcraft in two classes: a 10,000-20,000 Future Attack Air Vehicle capable of both tactical ground support and air-to-air missions, and a 60,000-80,000 lb Advanced Cargo Aircraft, for heavy-lift field-support operations. Specific ART objectives encompass a 25-percent reduction in drivetrain weight, a 10-dB noise level reduction at the transmission source, and the achievement of a 5000-hr MTBF. Four candidate drivetrain systems have been carried to a conceptual design stage, together with projections of their mission performance and life-cycle costs.

  8. Drive transmission means

    SciTech Connect

    Marsh, M. R.

    1985-01-15

    This invention provides apparatus for use in a drive transmission system comprising a pump adapted to perform work on a medium and means repetitively and automatically to unload the pump. When connected with a flywheel driven by a prime mover an embodiment alternately performs work and then is unloaded to permit acceleration of the flywheel. In use in a driven transmission system there is provided a flywheel driven by an engine, a pump driven by the flywheel, powered by the pump, and means repetitively to unload the pump permitting the engine to accelerate the flywheel and compensation means to power the hydraulic motor while the pump is unloaded. The pump is preferably a rotary positive displacement pump having relief galleries eliminating the seal between pumping elements driving each cycle.

  9. Geothermal district heating systems

    NASA Astrophysics Data System (ADS)

    Budney, G. S.; Childs, F.

    1982-06-01

    Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.

  10. Small passenger car transmission test; Chevrolet LUV transmission

    NASA Technical Reports Server (NTRS)

    Bujold, M. P.

    1980-01-01

    A 1978 Chevrolet LUV manual transmission tested per the applicable portions of a passenger car automatic transmission test code (SAE J65lb) which required drive performance, coast performance, and no load test conditions. Under these test conditions, the transmission attained maximum efficiencies in the upper ninety percent range for both drive performance tests and coast performance tests. The major results of this test (torque, speed, and efficiency curves) are presented. Graphs map the complete performance characteristics for the Chevrolet LUV transmission.

  11. Small passenger car transmission test; Ford C4 transmission

    NASA Technical Reports Server (NTRS)

    Bujold, M. P.

    1980-01-01

    A 1979 Ford C4 automatic transmission was tested per a passenger car automatic transmission test code (SAE J651b) which required drive performance, coast performance, and no load test conditions. Under these test conditions, the transmission attained maximum efficiencies in the mid-eighty percent range for both drive performance tests and coast performance tests. The major results of this test (torque, speed, and efficiency curves) are presented. Graphs map the complete performance characteristics for the Ford C4 transmission.

  12. Facsimile transmission standards

    NASA Astrophysics Data System (ADS)

    Mudry, Andrew; Poulin, Brad

    1993-10-01

    Modern tactical communications systems are becoming increasingly compatible with existing civilian systems. This compatibility allows the military to take advantage of the equipment available commercially and spare the expense of developing costly customized systems. It also increases the interoperability of various communications systems employed by allies involved in multinational operations. Finally, the compatibility allows the military to augment its telecommunications assets with existing commercial equipment and networks during times of conflict. One civilian communication standard that has recently been adopted by the military for tactical communications is that of facsimile. Facsimile is now commonly used on the battlefield for the transmission of tactical maps and situation reports. This technical note examines the requirements for facsimile transmission. An overview of the various facsimile standards are given, followed by a detailed description of the most commonly used standard; CCITT Group III. The Group III specifications are a composite of various CCITT modulation and encoding standards. These consist of V.21, V.27ter, and V.29 modulations, as well as T.4 image encoding standards, and T.30 signalling specifications. Each of these standards is described in the context of facsimile transmissions. A complete description of the handshaking which occurs between the facsimile transmitter and receiver is given.

  13. Compact change speed transmission

    SciTech Connect

    Iwanaga, K.; Yamaguchi, T.

    1989-06-06

    A change speed transmission is described comprising: a stationary part; an input member; an output member; first and second planetary gear sets; clutch and brake means for selectively controlling the first and second planetary gear sets to provide a plurality of forward speed rations and a reverse speed ratio between the input and output member; the clutch and brake means including a first clutch, a first one-way clutch, and a second one-way clutch which, when the first clutch is engaged, provide a path of transmission of reaction to the stationary part thereby establishing a path of transmission of torque through at least a part of the first and second planetary gear sets to achieve a predetermined one speed ratio of the forward speed ratios; the clutch and brake means including also a brake and a second slutch which, when both of the brake and the second clutch are engaged, hinder the action of the second one-way clutch and that of the first one-way clutch, respectively, thereby providing engine braking during running with the predetermined one speed ratio; the first clutch including means forming a drum-shaped member disposed radially outwardly of and receiving at least one of the first and second planetary gear sets, and an actuating piston of the first clutch; and the second clutch including an actuating piston slidably disposed within the actuating piston of the first clutch.

  14. Geothermal heating

    SciTech Connect

    Aureille, M.

    1982-01-01

    The aim of the study is to demonstrate the viability of geothermal heating projects in energy and economic terms and to provide nomograms from which an initial estimate may be made without having to use data-processing facilities. The effect of flow rate and temperature of the geothermal water on drilling and on the network, and the effect of climate on the type of housing are considered.

  15. Heat pump

    SciTech Connect

    Apte, A.J.

    1982-11-30

    A single working fluid heat pump system having a turbocompressor with a first fluid input for the turbine and a second fluid input for the compressor, and a single output volute or mixing chamber for combining the working fluid output flows of the turbine and the compressor. The system provides for higher efficiency than single fluid systems whose turbine and compressor are provided with separate output volutes.

  16. Intercultural Transmission of Values: The Role of Transmission Belts.

    ERIC Educational Resources Information Center

    Schonpflug, Ute

    2001-01-01

    Explored the effect of "transmission belts" (conditions favorable to cultural transmission within particular socioeconomic and cultural contexts) on the similarity of values between Turkish fathers and their sons. Data from father-son dyads in Germany indicated that transmission of values related to the collective value categories of…

  17. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1979-01-01

    An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchangers and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

  18. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1982-01-01

    An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchanges and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

  19. Experimental metrology to obtain thermal phonon transmission coefficients at solid interfaces

    NASA Astrophysics Data System (ADS)

    Hua, Chengyun; Chen, Xiangwen; Ravichandran, Navaneetha K.; Minnich, Austin J.

    2017-05-01

    Interfaces play an essential role in phonon-mediated heat conduction in solids, impacting applications ranging from thermoelectric waste heat recovery to heat dissipation in electronics. From the microscopic perspective, interfacial phonon transport is described by transmission coefficients that link vibrational modes in the materials composing the interface. However, direct experimental determination of these coefficients is challenging because most experiments provide a mode-averaged interface conductance that obscures the microscopic detail. Here, we report a metrology to extract thermal phonon transmission coefficients at solid interfaces using ab initio phonon transport modeling and a thermal characterization technique, time-domain thermoreflectance. In combination with transmission electron microscopy characterization of the interface, our approach allows us to link the atomic structure of an interface to the spectral content of the heat crossing it. Our work provides a useful perspective on the microscopic processes governing interfacial heat conduction.

  20. Heat transport in active harmonic chains

    SciTech Connect

    Zheng, Mei C.; Ellis, Fred M.; Kottos, Tsampikos; Fleischmann, Ragnar; Geisel, Theo; Prosen, Tomaz

    2011-08-15

    We show that a harmonic lattice model with amplifying and attenuating elements, when coupled to two thermal baths, exhibits unique heat transport properties. Some of these novel features include anomalous nonequilibrium steady-state heat currents, negative differential thermal conductance, as well as nonreciprocal heat transport. We find that when these elements are arranged in a PT-symmetric manner, the domain of existence of the nonequilibrium steady state is maximized. We propose an electronic experimental setup based on resistive-inductive-capacitive (RLC) transmission lines, where our predictions can be tested.

  1. Sound and heat revolutions in phononics.

    PubMed

    Maldovan, Martin

    2013-11-14

    The phonon is the physical particle representing mechanical vibration and is responsible for the transmission of everyday sound and heat. Understanding and controlling the phononic properties of materials provides opportunities to thermally insulate buildings, reduce environmental noise, transform waste heat into electricity and develop earthquake protection. Here I review recent progress and the development of new ideas and devices that make use of phononic properties to control both sound and heat. Advances in sonic and thermal diodes, optomechanical crystals, acoustic and thermal cloaking, hypersonic phononic crystals, thermoelectrics, and thermocrystals herald the next technological revolution in phononics.

  2. Heat-Exchanger/Heat-Pipe Interface

    NASA Technical Reports Server (NTRS)

    Snyder, H. J.; Van Hagan, T. H.

    1987-01-01

    Monolithic assembly reliable and light in weight. Heat exchanger and evaporator ends of heat pipes integrated in monolithic halves welded together. Interface assembly connects heat exchanger of furnace, reactor, or other power source with heat pipes carrying heat to radiator or power-consuming system. One of several concepts proposed for nuclear power supplies aboard spacecraft, interface useful on Earth in solar thermal power systems, heat engines, and lightweight cooling systems.

  3. Heat-Transfer Coupling For Heat Pipes

    NASA Technical Reports Server (NTRS)

    Nesmith, Bill J.

    1991-01-01

    Proposed welded heat-transfer coupling joins set of heat pipes to thermoelectric converter. Design avoids difficult brazing operation. Includes pair of mating flanged cups. Upper cup integral part of housing of thermoelectric converter, while lower cup integral part of plate supporting filled heat pipes. Heat pipes prefilled. Heat of welding applied around periphery of coupling, far enough from heat pipes so it would not degrade working fluid or create excessive vapor pressure in the pipes.

  4. Hydride heat pump with heat regenerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative hydride heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system. A series of at least four canisters containing a lower temperature performing hydride and a series of at least four canisters containing a higher temperature performing hydride is provided. Each canister contains a heat conductive passageway through which a heat transfer fluid is circulated so that sensible heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  5. Heat pipe waste heat recovery boilers

    NASA Astrophysics Data System (ADS)

    Littwin, D. A.; McCurley, J.

    The use of heat pipes as transport devices in waste heat recovery boilers is examined. Test results show that heat pipes can efficiently extract heat from the hot gas stream and transfer it inside the pressure vessel for the steam generation process. The benefits of incorporating heat pipes into the design of waste heat recovery boilers include a highly compact package, a significant reduction in thermally induced stresses, double isolation of the steam from the heat source, an extended surface for improved efficiency in heat extraction, improved circulation and stability in the boiling regime, easy cleaning, individually replaceable tubes, and low flue gas pressure drop.

  6. Heating systems for heating subsurface formations

    DOEpatents

    Nguyen, Scott Vinh [Houston, TX; Vinegar, Harold J [Bellaire, TX

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  7. Transmission speed sensor arrangement

    SciTech Connect

    Nogle, T.D.

    1986-05-06

    In an engine driven vehicle having an engine extending transversely with respect to the vehicle at one end thereof, a pair of wheels at the same end of the vehicle, and automatic drive transmission means connecting the engine to the wheels, the automatic drive transmission means includes a housing attached to the vehicle. The housing has a torque converter section, a speed change section adjacent the torque converter section, and a differential and transfer section; the engine having a crankshaft, a torque converter in the torque converter section of the housing rotatable on the same axis as the crankshaft and adapted to be driven by the engine crankshaft, the torque converter drivingly connected to one outer end of a transmission input shaft, the input shaft having its other inner end located about midway through the speed change section, a speed change section output shaft mounted coaxial with the input shaft in the speed change section with its inner end adjacent the input shaft inner end and its outer free end extending beyond the speed change section, an output gear having peripheral teeth formed thereon, the output gear connected on the output shaft outer free end such that the output shaft and the output gear rotate on the input shaft axis, a transfer shaft having a transfer gear engaged with the output gear, the output shaft having a bore extending axially therethrough, the improvement wherein; a speed sensor shaft having a speed sensor wheel with peripheral teeth formed thereon fixed on the free outer end thereof, means journally supporting the speed shaft concentrically within the output shaft bore such that the speed wheel is axially spaced closely adjacent to the output gear.

  8. Planetary Transmission Diagnostics

    NASA Technical Reports Server (NTRS)

    Lewicki, David G. (Technical Monitor); Samuel, Paul D.; Conroy, Joseph K.; Pines, Darryll J.

    2004-01-01

    This report presents a methodology for detecting and diagnosing gear faults in the planetary stage of a helicopter transmission. This diagnostic technique is based on the constrained adaptive lifting algorithm. The lifting scheme, developed by Wim Sweldens of Bell Labs, is a time domain, prediction-error realization of the wavelet transform that allows for greater flexibility in the construction of wavelet bases. Classic lifting analyzes a given signal using wavelets derived from a single fundamental basis function. A number of researchers have proposed techniques for adding adaptivity to the lifting scheme, allowing the transform to choose from a set of fundamental bases the basis that best fits the signal. This characteristic is desirable for gear diagnostics as it allows the technique to tailor itself to a specific transmission by selecting a set of wavelets that best represent vibration signals obtained while the gearbox is operating under healthy-state conditions. However, constraints on certain basis characteristics are necessary to enhance the detection of local wave-form changes caused by certain types of gear damage. The proposed methodology analyzes individual tooth-mesh waveforms from a healthy-state gearbox vibration signal that was generated using the vibration separation (synchronous signal-averaging) algorithm. Each waveform is separated into analysis domains using zeros of its slope and curvature. The bases selected in each analysis domain are chosen to minimize the prediction error, and constrained to have the same-sign local slope and curvature as the original signal. The resulting set of bases is used to analyze future-state vibration signals and the lifting prediction error is inspected. The constraints allow the transform to effectively adapt to global amplitude changes, yielding small prediction errors. However, local wave-form changes associated with certain types of gear damage are poorly adapted, causing a significant change in the

  9. Heat exchanger

    DOEpatents

    Brackenbury, Phillip J.

    1986-04-01

    A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively.

  10. Dynamically prioritized progressive transmission

    NASA Astrophysics Data System (ADS)

    Blanford, Ronald

    1992-04-01

    Retrieval of image data from a centralized database may be subject to bandwidth limitations, whether due to a low-bandwidth communications link or to contention from simultaneous accesses over a high-bandwidth link. Progressive transmission can alleviate this problem by encoding image data so that any prefix of the data stream approximates the complete image at a coarse level of resolution. The longer the prefix, the finer the resolution. In many cases, as little at 1 percent of the image data may be sufficient to decide whether to discard the image, to permit the retrieval to continue, or to restrict retrieval to a subsection of the image. Our approach treats resolution not as a fixed attribute of the image, but rather as a resource which may be allocated to portions of the image at the direction of a user-specified priority function. The default priority function minimizes error by allocating more resolution to regions of high variance. The user may also point to regions of interest requesting priority transmission. More advanced target recognition strategies may be incorporated at the user's discretion. Multispectral imagery is supported. The user engineering implications are profounded. There is immediate response to a query that might otherwise take minutes to complete. The data is transmitted in small increments so that no single user dominates the communications bandwidth. The user-directed improvement means that bandwidth is focused on interesting information. The user may continue working with the first coarse approximations while further image data is still arriving. The algorithm has been implemented in C on Sun, Silicon Graphics, and NeXT workstations, and in Lisp on a Symbolics. Transmission speeds reach as high as 60,000 baud using a Sparc or 68040 processor when storing data to memory; somewhat less if also updating a graphical display. The memory requirements are roughly five bytes per image pixel. Both computational and memory costs may be reduced

  11. Conventional transmission electron microscopy

    PubMed Central

    Winey, Mark; Meehl, Janet B.; O'Toole, Eileen T.; Giddings, Thomas H.

    2014-01-01

    Researchers have used transmission electron microscopy (TEM) to make contributions to cell biology for well over 50 years, and TEM continues to be an important technology in our field. We briefly present for the neophyte the components of a TEM-based study, beginning with sample preparation through imaging of the samples. We point out the limitations of TEM and issues to be considered during experimental design. Advanced electron microscopy techniques are listed as well. Finally, we point potential new users of TEM to resources to help launch their project. PMID:24482357

  12. Frictionless continuously variable transmission

    SciTech Connect

    Korban, J.F.; Korban, N.F.

    1989-07-25

    This patent describes an infinitely variable speed transmission. It comprises: an input shaft; a drive plate having a plurality of radial slots therein, the drive plate fixed to the input shaft; an output shaft parallel to the input shaft; a bevel gear fixed to the output shaft; a plurality if independently rotatable sprocketed pinions freely rotatable about and meshing with the bevel gear. The pinions also engaging the drive plate by projections from the pinions slidably mounted in the radial slots in the drive plate; and clutching means for selectively locking and unlocking the pinions in sequence to effect driving of the bevel gear.

  13. Offset Waveguide Transmission Measurements

    NASA Technical Reports Server (NTRS)

    Cravey, Robin

    1997-01-01

    This report describes measurements to determine transmission losses in S-band (2.60-3.95 GHz) waveguide sections due to misalignment of the sections relative to each other. The experiments were performed in support of the Hydrostar program to determine the feasibility of using deployable waveguide sections in a large space radiometer. The waveguide sections would possibly be hinged and folded for launch, then deployed in space to form long sections of waveguide. Since very low losses are required for radiometer applications, the effects of potential misalignment after deployment of the waveguide sections may be significant. These measurements were performed in the Electromagnetic Properties Measurement Laboratory in the Electromagnetics Research Branch.

  14. Regenerative Hydride Heat Pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1992-01-01

    Hydride heat pump features regenerative heating and single circulation loop. Counterflow heat exchangers accommodate different temperatures of FeTi and LaNi4.7Al0.3 subloops. Heating scheme increases efficiency.

  15. The Born transmission eigenvalue problem

    NASA Astrophysics Data System (ADS)

    Cakoni, Fioralba; Colton, David; Rezac, Jacob D.

    2016-10-01

    In this paper we study the distribution of transmission eigenvalues in the complex plane for obstacles whose contrast is small in magnitude. We use a first order approximation of the refractive index to derive and study an approximate interior transmission problem. In the case of spherically stratified media, we prove existence and discreteness of transmission eigenvalues and derive a condition under which the complex part of transmission eigenvalues cannot lie in a strip parallel to the real axis. For obstacles with general shape, we demonstrate that if transmission eigenvalues exist then they form a discrete set.

  16. Household Transmission of Influenza Virus.

    PubMed

    Tsang, Tim K; Lau, Lincoln L H; Cauchemez, Simon; Cowling, Benjamin J

    2016-02-01

    Human influenza viruses cause regular epidemics and occasional pandemics with a substantial public health burden. Household transmission studies have provided valuable information on the dynamics of influenza transmission. We reviewed published studies and found that once one household member is infected with influenza, the risk of infection in a household contact can be up to 38%, and the delay between onset in index and secondary cases is around 3 days. Younger age was associated with higher susceptibility. In the future, household transmission studies will provide information on transmission dynamics, including the correlation of virus shedding and symptoms with transmission, and the correlation of new measures of immunity with protection against infection.

  17. [Oral transmission of Chagas' disease].

    PubMed

    Toso M, Alberto; Vial U, Felipe; Galanti, Norbel

    2011-02-01

    The traditional transmission pathways of Chagas' disease are vectorial, transfusional, transplacental and organ transplantation. However, oral transmission is gaining importance. The first evidence of oral transmission was reported in Brazil in 1965. Nowadays the oral route is the transmission mode in 50% of cases in the Amazon river zone. Oral infection is produced by the ingestion of infected triatomine bugs or their feces, undercooked meat from infested host animals and food contaminated with urine or anal secretion of infected marsupials. Therefore travelers to those zones should be advised about care to be taken with ingested food. In Chile, this new mode of transmission should be considered in public health policies.

  18. Colorado Electrical Transmission Grid

    DOE Data Explorer

    Zehner, Richard E.

    2012-02-01

    Citation Information: Originator: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Originator: Xcel Energy Publication Date: 2012 Title: Colorado XcelEnergy NonXcel Transmission Network Edition: First Publication Information: Publication Place: Earth Science & Observation Center, Cooperative Institute for Research in Environmental Science (CIRES), University of Colorado, Boulder Publisher: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Description: This layer contains transmission network of Colorado Spatial Domain: Extent: Top: 4540689.017558 m Left: 160606.141934 m Right: 758715.946645 m Bottom: 4098910.893397m Contact Information: Contact Organization: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Contact Person: Khalid Hussein Address: CIRES, Ekeley Building Earth Science & Observation Center (ESOC) 216 UCB City: Boulder State: CO Postal Code: 80309-0216 Country: USA Contact Telephone: 303-492-6782 Spatial Reference Information: Coordinate System: Universal Transverse Mercator (UTM) WGS’1984 Zone 13N False Easting: 500000.00000000 False Northing: 0.00000000 Central Meridian: -105.00000000 Scale Factor: 0.99960000 Latitude of Origin: 0.00000000 Linear Unit: Meter Datum: World Geodetic System ’1984 (WGS ’1984) Prime Meridian: Greenwich Angular Unit: Degree Digital Form: Format Name: Shapefile

  19. Transmissible encephalopathies in animals.

    PubMed Central

    Kimberlin, R H

    1990-01-01

    Scrapie in sheep and goats is the best known of the transmissible encephalopathies of animals. The combination of maternal transmission of infection and long incubation periods effectively maintains the infection in flocks. A single sheep gene (Sip) controls both experimental and natural scrapie and the discovery of allelic markers could enable the use of sire selection in the control of the natural disease. Studies of experimental rodent scrapie show that neuroinvasion occurs by spread of infection from visceral lymphoreticular tissues along nerve fibers to mid-thoracic cord. The slowness of scrapie is due to restrictions on replication and cell-to-cell spread of infection affecting neuroinvasion and subsequent neuropathogenesis. Probably both stages in mice are controlled by Sinc gene, the murine equivalent of Sip. The glycoprotein PrP may be the normal product of Sinc gene. Posttranslationally modified PrP forms the disease specific "scrapie associated fibrils" and may also be a constituent of the infectious agent. Scrapie-like diseases have been reported in mink and several species of ruminants including cattle. All of them may be caused by the recycling of scrapie infected sheep material in animal feed. The human health implications are discussed. PMID:2407328

  20. Transmission shift mechanism

    SciTech Connect

    Smith, R.R.

    1989-06-20

    This patent describes a mechanism for selecting the gear of an automatic transmission in a vehicle. The mechanism consists of: a pressure source; a gear selection valve having an inlet means for receiving fluid from the pressure source, first outlet ports, and second outlet ports; a manual override means for opening and blocking communication between the pressure source and the first ports and for simultaneously opening and blocking communication between the pressure source and the second outlet ports; a port selector means within the valve for controlling flow through the second ports, the port selector means being movable to a plurality of positions, each position permitting a selected second outlet port to open; a selector control mans for moving the port selector means from one position to another, the selector control means including a planetary gear set connected by an input shaft to the transmission and connected to a vehicle load by an output shaft, the planetary gear set having a ring gear whose angular position is a function of reaction torque imposed by the load on the output shaft, the selector control means further including an arm assembly connected between the ring gear and the port selector means so that the position of the port selector means is a function of the reaction torque on the output shaft.

  1. Simplified power shift transmission

    SciTech Connect

    Michael, R.A.

    1987-04-21

    A multi-speed transmission is described for transferring power between a first shaft and a second shaft, the transmission comprising: a compound planetary assembly including a sun gear, a ring gear concentric with the sun gear, a reaction gear concentric with the ring gear, a planetary gear carrier rotatably supporting first and second sets of planet gears, the first planet gear set intermeshing with the ring gear. The sun gear and the second planet gear set intermesh with the first planet gear set and the reaction gear, means for selectively coupling the first shaft with the sun gear and the reaction gear, and means for selectively preventing rotation of the ring gear, and reaction gear and the planetary carrier; a simple planetary assembly comprising a sun gear component concentric with the sun gear of the compound planetary assembly, a ring gear component concentric with both of the sun gears, and a planetary gear carrier component rotatably supporting a set of planet gears, the planet gear set meshing with the sun gear and the ring gear of the simple planetary.

  2. Automatic transmission structure

    SciTech Connect

    Iwase, Y.; Morisawa, K.

    1987-03-24

    An automatic transmission is described comprising: an output shaft of the transmission including a stepped portion; a parking gear spline-connected with the output shaft on a first side of the stepped portion; a plurality of governor values mounted on a rear side of the parking gear and radially disposed around the output shaft on the first side of the stepped portion; a speed meter drive gear spline-connected with the output shaft on a second side of the stepped portion and on a rear side of the governor valves; and an annular spacer fitted on the output shaft on the second side of the stepped portion between the governor valves and the speed meter drive gear to abut on each of the governor valves and the speed meter drive gear. The annular member is constructed separately from the speed meter drive gear and has an outer diameter larger than an outer diameter of the speed meter drive gear thereby resulting in a contact area between the annular space and the speed meter drive gear which is smaller than a contact area between the annular spacer and the rear side of the governor valves; the drive gear being axially secured relative to the output shaft by a bearing thereby enabling a fixed axial positioning of the annular spacer on the output shaft.

  3. Broadband transmission EPR spectroscopy.

    PubMed

    Hagen, Wilfred R

    2013-01-01

    EPR spectroscopy employs a resonator operating at a single microwave frequency and phase-sensitive detection using modulation of the magnetic field. The X-band spectrometer is the general standard with a frequency in the 9-10 GHz range. Most (bio)molecular EPR spectra are determined by a combination of the frequency-dependent electronic Zeeman interaction and a number of frequency-independent interactions, notably, electron spin - nuclear spin interactions and electron spin - electron spin interactions, and unambiguous analysis requires data collection at different frequencies. Extant and long-standing practice is to use a different spectrometer for each frequency. We explore the alternative of replacing the narrow-band source plus single-mode resonator with a continuously tunable microwave source plus a non-resonant coaxial transmission cell in an unmodulated external field. Our source is an arbitrary wave digital signal generator producing an amplitude-modulated sinusoidal microwave in combination with a broadband amplifier for 0.8-2.7 GHz. Theory is developed for coaxial transmission with EPR detection as a function of cell dimensions and materials. We explore examples of a doublet system, a high-spin system, and an integer-spin system. Long, straigth, helical, and helico-toroidal cells are developed and tested with dilute aqueous solutions of spin label hydroxy-tempo. A detection limit of circa 5 µM HO-tempo in water at 800 MHz is obtained for the present setup, and possibilities for future improvement are discussed.

  4. Transmission shift control assembly

    SciTech Connect

    Dzioba, D.L.

    1989-04-18

    This patent describes a transmission shift control assembly mounted on a steering column having a longitudinal axis comprising: bracket means secured to the steering column; transmission shift cable means having a portion secured to the bracket means and a portion linearly movable relative to the secured portion; mounting means on the bracket cable drive arm means having an axis and being rotatably mounted on the rotary axis on the mounting means oblique to the longitudinal axis and including a cable connecting portion secured to the movable portion of the cable means and lever mounting means adjacent the mounting means; operator control means including lever means, pin means for pivotally mounting the lever means on the lever mounting means on an axis substantially perpendicular to the rotary axis and positioning arm means formed on the lever means and extending from the pin means; and detent gate means disposed on the bracket means in position to abut the positioning arm means for limiting the extent of pivotal movement of the lever means.

  5. Heat pipe methanator

    DOEpatents

    Ranken, William A.; Kemme, Joseph E.

    1976-07-27

    A heat pipe methanator for converting coal gas to methane. Gravity return heat pipes are employed to remove the heat of reaction from the methanation promoting catalyst, transmitting a portion of this heat to an incoming gas pre-heat section and delivering the remainder to a steam generating heat exchanger.

  6. Latent Heat in Soil Heat Flux Measurements

    USDA-ARS?s Scientific Manuscript database

    The surface energy balance includes a term for soil heat flux. Soil heat flux is difficult to measure because it includes conduction and convection heat transfer processes. Accurate representation of soil heat flux is an important consideration in many modeling and measurement applications. Yet, the...

  7. Segmented heat exchanger

    DOEpatents

    Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

    2010-12-14

    A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

  8. Dual source heat pump

    DOEpatents

    Ecker, Amir L.; Pietsch, Joseph A.

    1982-01-01

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

  9. Heat recovery method

    SciTech Connect

    Richarts, F.

    1985-04-16

    Heat is recovered by combining a heat transfer system including heat exchangers interconnected in a circulatory system, with a heat pump system. The heat pump system is preferably operated in accordance with the Lorenz-Principle. It is not necessary to divide the heat carrier circuit of the heat pump into two or three separate circulatory circuits. The heat carrier circuit of the heat pump can thus continue to operate unchanged even if the heat pump is switched off. For this purpose the warm heat carrier coming from a discharge fluid cooler, is heated further in a condenser of the heat pump and the cold heat carrier coming from a preheater or cooler group, is cooled further in an evaporator of the heat pump.

  10. A solar heating system with annual storage

    NASA Astrophysics Data System (ADS)

    Lazzari, F.; Raffellini, G.

    1981-07-01

    A solar heated house with long term storage capability, built in Trento, Italy, is described. The one story house was built from modular components and has a total heated volume of 1130 cu m. Flat plate solar collectors with a water-antifreeze medium are located beneath the lawn, and six cylindrical underground tanks holding 130 cu m of water heated by thermal energy from the collectors are situated under the garden. The house walls have an 8 cm cavity filled with 5 cm of formaldehyde foam, yielding a heat transmission (U) of 0.37 W/sq m/deg C. The roof and ceilings are insulated with fiberglass and concrete, producing U-values of 0.46 W/sq m/deg C and 0.57 W/sq m/deg C, respectively. Heat pumps using 6 kW move thermal energy between the house and the tanks. Direct hot water heating occurs in the summer, and direct home heating when the stored water temperature exceeds 32 C. A computer model was developed which traces the annual heat flow and it is shown that the system supplies all heating requirements for the house, with electrical requirements equal to 20 percent of the annual house needs.

  11. Pressure transmission area and maximum pressure transmission of different thermoplastic resin denture base materials under impact load.

    PubMed

    Nasution, Hubban; Kamonkhantikul, Krid; Arksornnukit, Mansuang; Takahashi, Hidekazu

    2017-06-09

    The purposes of the present study were to examine the pressure transmission area and maximum pressure transmission of thermoplastic resin denture base materials under an impact load, and to evaluate the modulus of elasticity and nanohardness of thermoplastic resin denture base. Three injection-molded thermoplastic resin denture base materials [polycarbonate (Basis PC), ethylene propylene (Duraflex), and polyamide (Valplast)] and one conventional heat-polymerized acrylic resin (PMMA, SR Triplex Hot) denture base, all with a mandibular first molar acrylic resin denture tooth set in were evaluated (n=6). Pressure transmission area and maximum pressure transmission of the specimens under an impact load were observed by using pressure-sensitive sheets. The modulus of elasticity and nanohardness of each denture base (n=10) were measured on 15×15×15×3mm(3) specimen by using an ultramicroindentation system. The pressure transmission area, modulus of elasticity, and nanohardness data were statistically analyzed with 1-way ANOVA, followed by Tamhane or Tukey HSD post hoc test (α=.05). The maximum pressure transmission data were statistically analyzed with Kruskal-Wallis H test, followed by Mann-Whitney U test (α=.05). Polymethyl methacrylate showed significantly larger pressure transmission area and higher maximum pressure transmission than the other groups (P<.001). Significant differences were found in modulus of elasticity and nanohardness among the four types of denture bases (P<.001). Pressure transmission area and maximum pressure transmission varied among the thermoplastic resin denture base materials. Differences in the modulus of elasticity and nanohardness of each type of denture base were demonstrated. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  12. Small passenger car transmission test: Mercury Lynx ATX transmission

    SciTech Connect

    Bujold, M P

    1981-09-01

    The small passenger car transmission test was initiated to supply electric vehicle manufacturers with technical information regarding the performance of commercially available transmissions. This information would enable EV manufacturers to design a more energy efficient vehicle. With this information the manufacturers would be able to estimate vehicle driving range as well as speed and torque requirements for specific road load performance characteristics. This report covers the 1981 Mercury Lynx ATX transaxle. This transmission was tested per a passenger car automatic transmission test code (SAE J65lb) which required drive performance, coast performance, and no load test conditions. Under these test conditions the transmission attained maximum efficiencies in the 93% range for drive performance tests. The major results of this test are the torque, speed and efficiency curves which are located in the data section of this report. These graphs map performance characteristics for the Mercury Lynx ATX transmission.

  13. Small passenger car transmission test-Chevrolet 200 transmission

    NASA Technical Reports Server (NTRS)

    Bujold, M. P.

    1980-01-01

    The small passenger car transmission was tested to supply electric vehicle manufacturers with technical information regarding the performance of commerically available transmissions which would enable them to design a more energy efficient vehicle. With this information the manufacturers could estimate vehicle driving range as well as speed and torque requirements for specific road load performance characteristics. A 1979 Chevrolet Model 200 automatic transmission was tested per a passenger car automatic transmission test code (SAE J651b) which required drive performance, coast performance, and no load test conditions. The transmission attained maximum efficiencies in the mid-eighty percent range for both drive performance tests and coast performance tests. Torque, speed and efficiency curves map the complete performance characteristics for Chevrolet Model 200 transmission.

  14. Molecular Detection and Phonon Filtering in Heat-Transfer Spectroscopy

    NASA Astrophysics Data System (ADS)

    Walczak, Kamil; Yerkes, Kirk

    2014-03-01

    We examine heat transport carried by acoustic phonons in the systems composed of nanoscale chains of masses coupled to two thermal baths of different temperatures. Thermal conductance is obtained by using linearized Landauer formula for heat flux with phonon transmission probability calculated within atomistic Green's functions (AGF) method. AGF formalism is extended onto dissipative chains of masses with harmonic coupling beyond nearest-neighbor approximation, while atomistic description of heat reservoirs is also included into computational scheme. The resonant structure of phonon transmission spectrum is analyzed with respect to reservoir-dimensionality effects, molecular damping, and mass-to-mass harmonic coupling. Analysis of transmission zeros (antiresonances) and their accompanied Fano-shape resonances are discussed as a result of interference effects between different vibrational modes. Specifically, we show that the heat-transfer-based characterization method may be used to identify individual molecules or filter out specific phonon modes from the whole frequency spectrum. This work is supported by AFOSR grant.

  15. The automated command transmission

    NASA Astrophysics Data System (ADS)

    Inoue, Y.; Satoh, S.

    A technique for automated command transmission (ACT) to GEO-stationed satellites is presented. The system is intended for easing the command center workload. The ACT system determines the relation of the commands to on-board units, connects the telemetry with on-board units, defines the control path on the spacecraft, identifies the correspondence of back-up units to primary units, and ascertains sunlight or eclipse conditions. The system also has the address of satellite and command decoders, the ID and content for the mission command sequence, group and inhibit codes, a listing of all available commands, and restricts the data to a command sequence. Telemetry supplies data for automated problem correction. All other missions operations are terminated during system recovery data processing after a crash. The ACT system is intended for use with the GMS spacecraft.

  16. Transmission seal development

    NASA Technical Reports Server (NTRS)

    Brien, M.

    1977-01-01

    An experimental evaluation was performed on a high-speed (72.9 m/s, 14,349 ft/min) transmission seal of the synergistic type. During testing of the seal, oil leakage occurred at positive bearing cavity pressures. Modifications were made in an attempt to eliminate the leakage but none were completely successful. Leakage appears to be the result of questionable positioning of the sealing elements resulting in inadequate shaft contact by the oil side sealing element. This condition may be related to the nonsymmetrical shape of the elastomeric retainer and to dimensional changes caused by swelling of the elastomeric retainer from exposure to the sealed fluid. Indications of a speed dependent leakage characteristic were also observed.

  17. Nonlinear transmission sputtering

    NASA Astrophysics Data System (ADS)

    Bitensky, I. S.; Sigmund, P.

    1996-05-01

    General expressions have been derived for the nonlinear yield of transmission sputtering for an incident polyatomic ion under the assumption that the molecule breaks up on entering the target and that sputter yields are enhanced due to proximity of atomic trajectories. Special attention is given to the case of negligible Coulomb explosion where projectile atoms penetrate independently. For weakly overlapping trajectories, the yield enhancement factor of a polyatomic molecule can be expressed by that of a diatom, amended with a correction for triple correlations if necessary. This expression is in good agreement with recent experimental findings on phenylalanine targets. Pertinent results on multiple scattering of atomic ions are reviewed and applied to independently-moving fragment atoms. The merits of measurements at variable layer thickness in addition to variable projectile energy are mentioned.

  18. Astrocytes Potentiate Synaptic Transmission

    NASA Astrophysics Data System (ADS)

    Nadkarni, Suhita

    2005-03-01

    A recent experimental study shows that astrocytes, a subtype of glia, are able to influence the spontaneous activity in the brain via calcium dependent glutamate release. We model the coupling mechanism between an astrocyte and a neuron based on experimental data. This coupling is dynamic and bi-directional, such that the modulations in intracellular calcium concentrations in astrocytes affect neuronal excitability and vice versa via a glutamatergic pathway. We demonstrate through simple neural-glial circuits that increases in the intracellular calcium concentration in astrocytes nearby can enhance spontaneous activity in a neuron, a significant mechanism said to be involved in plasticity and learning. The pattern of this marked increase in spontaneous firing rate in our model quantitatively follows that observed in the experiment. Further, depending on the type of synaptic connections diverging from the neuron, it can either inhibit or excite the ensuing dynamics and potentiate synaptic transmission, thus reinstating the integral role played by astrocytes in normal neuronal dynamics.

  19. 2D divertor heat flux distribution using a 3D heat conduction solver in National Spherical Torus Experiment.

    PubMed

    Gan, K F; Ahn, J-W; Park, J-W; Maingi, R; McLean, A G; Gray, T K; Gong, X; Zhang, X D

    2013-02-01

    The divertor heat flux footprint in tokamaks is often observed to be non-axisymmetric due to intrinsic error fields, applied 3D magnetic fields or during transients such as edge localized modes. Typically, only 1D radial heat flux profiles are analyzed; however, analysis of the full 2D divertor measurements provides opportunities to study the asymmetric nature of the deposited heat flux. To accomplish this an improved 3D Fourier analysis method has been successfully applied in a heat conduction solver (TACO) to determine the 2D heat flux distribution at the lower divertor surface in the National Spherical Torus Experiment (NSTX) tokamak. This advance enables study of helical heat deposition onto the divertor. In order to account for heat transmission through poorly adhered surface layers on the divertor plate, a heat transmission coefficient, defined as the surface layer thermal conductivity divided by the thickness of the layer, was introduced to the solution of heat conduction equation. This coefficient is denoted as α and a range of values were tested in the model to ensure a reliable heat flux calculation until a specific value of α led to the constant total deposited energy in the numerical solution after the end of discharge. A comparison between 1D heat flux profiles from TACO and from a 2D heat flux calculation code, THEODOR, shows good agreement. Advantages of 2D heat flux distribution over the conventional 1D heat flux profile are also discussed, and examples of 2D data analysis in the study of striated heat deposition pattern as well as the toroidal degree of asymmetry of peak heat flux and heat flux width are demonstrated.

  20. Broadband Transmission EPR Spectroscopy

    PubMed Central

    Hagen, Wilfred R.

    2013-01-01

    EPR spectroscopy employs a resonator operating at a single microwave frequency and phase-sensitive detection using modulation of the magnetic field. The X-band spectrometer is the general standard with a frequency in the 9–10 GHz range. Most (bio)molecular EPR spectra are determined by a combination of the frequency-dependent electronic Zeeman interaction and a number of frequency-independent interactions, notably, electron spin – nuclear spin interactions and electron spin – electron spin interactions, and unambiguous analysis requires data collection at different frequencies. Extant and long-standing practice is to use a different spectrometer for each frequency. We explore the alternative of replacing the narrow-band source plus single-mode resonator with a continuously tunable microwave source plus a non-resonant coaxial transmission cell in an unmodulated external field. Our source is an arbitrary wave digital signal generator producing an amplitude-modulated sinusoidal microwave in combination with a broadband amplifier for 0.8–2.7 GHz. Theory is developed for coaxial transmission with EPR detection as a function of cell dimensions and materials. We explore examples of a doublet system, a high-spin system, and an integer-spin system. Long, straigth, helical, and helico-toroidal cells are developed and tested with dilute aqueous solutions of spin label hydroxy-tempo. A detection limit of circa 5 µM HO-tempo in water at 800 MHz is obtained for the present setup, and possibilities for future improvement are discussed. PMID:23555819

  1. Laptop image transmission equipment

    NASA Astrophysics Data System (ADS)

    Mocenter, Michael M.

    1991-12-01

    Imagery and other visual information have become a critical element in planning and performing modern military operations. The effectiveness of this imagery information is often directly tied to the time it takes to get from the collector of this imagery to the user of the imagery. Hard copy distribution of annotated imagery to the tactical commander is hampered by the lack of effective communications paths, and the tactical use of hand held imagery is restricted by the lack of film processing facilities. The military has begun to rely on electronic imagery and digital communications technology for answers, with some success. The new obstacles created by applied electronic imagery are interoperability standards and effective use of communications bandwidth in a tactical environment. New technological developments in computer hardware/software have changed this situation by allowing for the gathering, dissemination, and transfer of near-real-time information to various intelligence audiences at any location. The Naval Air Development Center (NAVAIRDEVCEN) has coupled commercial-off-the-shelf (COTS) technology with National Image Transmission Formats (NITF) Standards to develop a Secondary Imagery Dissemination System (SIDS) package that is designed to meet the flexibility challenge of the tactical military environment. This tailorable SIDS package is called Laptop Image Transmission Equipment (LITE). The LITE system is an extension of the Navy's existing Fleet Imagery Support Terminal (FIST) into the man-portable tactical environment. As such, LITE development is focused on developing flexible imagery input (from sources such as filmless cameras) and connectivity to tactical communications paths and ruggedization/miniaturization issues. The LITE system, in prototype form, has already found application through operational use in special operations, counter narcotics operations, and classic air/ground/sea military operations. This paper provides an overview of the

  2. Technology of optical azimuth transmission

    NASA Astrophysics Data System (ADS)

    Lu, Honggang; Hu, Chunsheng; Wang, Xingshu; Gao, Yang

    2012-11-01

    It often needs transfer a reference from one place to another place in aerospace and guided missile launching. At first, principles of several typical optical azimuth transmission methods are presented. Several typical methods are introduced, such as Theodolite (including gyro-theodolite) collimation method, Camera series method, Optical apparatus for azimuth method and polarization modulated light transmission method. For these typical azimuth transmission methods, their essential theories are elaborated. Then the devices, the application fields and limitations of these typical methods' are presented. Theodolite (including gyro-theodolite) collimation method is used in the ground assembly of spacecraft. Camera series method and optical apparatus for azimuth method are used in azimuth transmission between different decks of ship. Polarization modulated light transmission method is used in azimuth transmission of rocket and guided missile. At the last, the further developments of these methods are discussed.

  3. Handbook on heat exchangers

    NASA Astrophysics Data System (ADS)

    Bazhan, Pavel I.; Kanevets, Georgii E.; Seliverstov, Vladimir M.

    Essential data on heat exchange equipment used in ship, locomotive, automotive, and aircraft powerplants are presented in a systematic manner. The data cover the principal types and technical and performance characteristics of heat exchangers, fundamentals of the theory of heat exchange, calculation of heat transfer coefficients for different types of heat exchange apparatus, optimization of heat exchangers, computer-aided design of heat exchange equipment, testing techniques, and test result processing.

  4. Thulium-170 heat source

    SciTech Connect

    Walter, C.E.; Van Konynenburg, R.; Van Sant, J.H.

    1992-01-21

    This patent describes an isotopic heat source. It comprises; at least one isotopic fuel stack, comprising alternating layers of: thulium oxide; and a low atomic weight diluent for thulium oxide; a heat block defining holes into which the fuel stacks can be placed; at least one heat pipe for heat removal, with the heat pipe being positioned in the heat block in thermal connection with the fuel stack; and a structural container surrounding the heat block.

  5. Nonazeotropic Heat Pump

    NASA Technical Reports Server (NTRS)

    Ealker, David H.; Deming, Glenn

    1991-01-01

    Heat pump collects heat from water circulating in heat-rejection loop, raises temperature of collected heat, and transfers collected heat to water in separate pipe. Includes sealed motor/compressor with cooling coils, evaporator, and condenser, all mounted in outer housing. Gradients of temperature in evaporator and condenser increase heat-transfer efficiency of vapor-compression cycle. Intended to recover relatively-low-temperature waste heat and use it to make hot water.

  6. Dielectric Nonlinear Transmission Line (Postprint)

    DTIC Science & Technology

    2011-12-01

    Technical Paper 3. DATES COVERED (From - To) 2011 4. TITLE AND SUBTITLE Dielectric Nonlinear Transmission Line (POSTPRINT) 5a. CONTRACT NUMBER...14. ABSTRACT A parallel plate nonlinear transmission line (NLTL) was constructed. Periodic loading of nonlinear dielectric slabs provides the...846-9101 Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. 239.18 Dielectric Nonlinear Transmission Line David M. French, Brad W. Hoff

  7. High heat flux single phase heat exchanger

    NASA Technical Reports Server (NTRS)

    Valenzuela, Javier A.; Izenson, Michael G.

    1990-01-01

    This paper presents the results obtained to date in a program to develop a high heat flux, single-phase heat exchanger for spacecraft thermal management. The intended application is a net generation interface heat exchanger to couple the crew module water thermal bus to the two-phase ammonia main thermal bus in the Space Station Freedom. The large size of the interface heat exchanger is dictated by the relatively poor water-side heat transfer characteristics. The objective of this program is to develop a single-phase heat transfer approach which can achieve heat fluxes and heat transfer coefficients comparable to those of the evaporation ammonia side. A new heat exchanger concept has been developed to meet these objecties. The main feature of this heat exchanger is that it can achieve very high heat fluxes with a pressure drop one to two orders of magnitude lower than those of previous microchannel or jet impingement high heat flux heat exchangers. This paper describes proof-of-concept experiments performed in air and water and presents analytical model of the heat exchanger.

  8. High heat flux single phase heat exchanger

    NASA Technical Reports Server (NTRS)

    Valenzuela, Javier A.; Izenson, Michael G.

    1990-01-01

    This paper presents the results obtained to date in a program to develop a high heat flux, single-phase heat exchanger for spacecraft thermal management. The intended application is a net generation interface heat exchanger to couple the crew module water thermal bus to the two-phase ammonia main thermal bus in the Space Station Freedom. The large size of the interface heat exchanger is dictated by the relatively poor water-side heat transfer characteristics. The objective of this program is to develop a single-phase heat transfer approach which can achieve heat fluxes and heat transfer coefficients comparable to those of the evaporation ammonia side. A new heat exchanger concept has been developed to meet these objecties. The main feature of this heat exchanger is that it can achieve very high heat fluxes with a pressure drop one to two orders of magnitude lower than those of previous microchannel or jet impingement high heat flux heat exchangers. This paper describes proof-of-concept experiments performed in air and water and presents analytical model of the heat exchanger.

  9. Multi-speed powershift transmission

    SciTech Connect

    Horsch, J.

    1989-08-22

    This patent describes a multi-speed powershift transmission for connection to a driven power shift. The transmission comprising: a speed transmission assembly including a speed input section connectable to the power shaft for selectively producing either of at least two forward input speed ratios having a relatively small speed ratio differential therebetween; a speed output section for selectively producing any one of at least three equally different forward output speed ratios and at least one reverse speed ratio. The input section comprising a pair of clutch operated drive gears mounted on a speed input shaft and hydraulically actuated in an alternative manner. The output section comprising a plurality of driven gears including a reverse gear mounted on a common speed output shaft, each driven gear having a hydraulically actuated clutch for connecting a selected driven gear to the speed output shaft; and a cluster gear assembly interconnecting the input and output section. The cluster gear assembly being selectively driven by either of the clutch operated drive gears, and a range transmission assembly for selectively producing any one of at least three equally different forward speed ranges. The range transmission assembly including a range input shaft which is operably coupled to the speed output shaft of the speed transmission assembly, a transmission output shaft, and a plurality of hydraulic clutch actuated gears interposed between the range input shaft and the transmissions output shaft and a master clutch assembly selectively interconnecting the speed and range transmission assemblies.

  10. Airborne transmission of Bordetella pertussis.

    PubMed

    Warfel, Jason M; Beren, Joel; Merkel, Tod J

    2012-09-15

    Pertussis is a contagious, acute respiratory illness caused by the bacterial pathogen Bordetella pertussis. Although it is widely believed that transmission of B. pertussis occurs via aerosolized respiratory droplets, no controlled study has ever documented airborne transmission of pertussis. We set out to determine if airborne transmission occurs between infected and naive animals, utilizing the baboon model of pertussis. Our results showed that 100% of exposed naive animals became infected even when physical contact was prevented, demonstrating that pertussis transmission occurs via aerosolized respiratory droplets.

  11. Solar heating

    SciTech Connect

    Resnick, M.; Startevant, R.C.

    1985-01-22

    A solar heater has an outlet conduit above an inlet conduit intercoupling a solar heating chamber with the inside of a building through a window opening. In one form the solar collecting chamber is outside the building below the window and the outlet conduit and inlet conduit are contiguous and pass through the window opening between the windowsill and the lower sash. In another form of the invention the solar collecting chambers are located beside each side of the window and joined at the top by the outlet conduit that passes through an opening between the upper window sash and the top of the window frame and at the bottom by an inlet conduit that passes through an opening between the lower sash and the windowsill. The outlet conduit carries photoelectric cells that provide electrical energy for driving a squirrel-cage fan in the outlet conduit through a mercury switch seated on a damper actuated by a bimetallic coil that closes the damper when the temperature in the outlet conduit goes below a predetermined temperature.

  12. Multiple source heat pump

    DOEpatents

    Ecker, Amir L.

    1983-01-01

    A heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating a fluid in heat exchange relationship with a refrigerant fluid, at least three refrigerant heat exchangers, one for effecting heat exchange with the fluid, a second for effecting heat exchange with a heat exchange fluid, and a third for effecting heat exchange with ambient air; a compressor for compressing the refrigerant; at least one throttling valve connected at the inlet side of a heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circuit and pump for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and directional flow of refrigerant therethrough for selecting a particular mode of operation. Also disclosed are a variety of embodiments, modes of operation, and schematics therefor.

  13. Heat powered refrigeration compressor

    NASA Astrophysics Data System (ADS)

    Goad, R. R.

    This prototype will be of similar capacity as the compressor that will eventually be commercially produced. This unit can operate on almost any moderate temperature water heat source. This heat source could include such applications as industrial waste heat, solar, wood burning stove, resistance electrical heat produced by a windmill, or even perhaps heat put out by the condenser of another refrigeration system.

  14. Heat pipe technology

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A bibliography of heat pipe technology to provide a summary of research projects conducted on heat pipes is presented. The subjects duscussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design and fabrication, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.

  15. Heated tool for autoclaves

    NASA Technical Reports Server (NTRS)

    Serafini, T. T.; Vanucci, R. D.; Cavano, P. J.; Winters, W. E.

    1980-01-01

    Components made of composite materials are heated in autoclaves by employing electrical resistance heating blankets, thus avoiding need to heat entire autoclave volume. Method provides not only significant energy savings compared to heating entire pressure vessel but offers time savings in accelerated heat-up and cool-down cycles.

  16. Transmissive Microshutter Arrays

    NASA Astrophysics Data System (ADS)

    Kutyrev, A. S.; Moseley, H. S.; Fettig, R. K.; Kuhn, J. L.; Woodgate, B. E.; Kimble, R. A.; Orloff, J. H.

    1999-12-01

    We report further progress on the development of a two-dimensional array of microshutters, which can be used as a high efficiency, high contrast field selection device for a multi-object spectrometer for the Next Generation Space Telescope (NGST). The device is a close packed array of shutters, with a typical size of 100 microns square and an area filling factor of up to 80%. Each shutter, made of single crystal silicon or silicon nitride with an appropriate optical coating, pivots on a torsion flexure along one edge. Each of the shutters is individually selectable. Although these devices can be used as reflection devices, their primary mode of operation is in transmission, which provides the minimum possible level of scattered light. An original double-shutter mechanism is employed for actuation. Small shutter arrays have been built using a Focus Ion Beam milling machine is a 3 x 3 double shutter actuation with a micro-manipulator under electron microscope observation has been demonstrated. An important aspect of this study has been to demonstrate the reliability of the structures over its expected lifetime. We analyzed stiffness, strength and fatigue issues of two good candidate materials, single crystal silicon and silicon nitride. Both appear to be suitable from the mechanical point of view. This project is supported by NASA grants.

  17. Transmission of digital data

    USGS Publications Warehouse

    Showen, Charles R.

    1971-01-01

    The Geological Survey, Water Resources Division, established a pilot project to evaluate equipment that would transmit date recorded on 16-channel paper tapes over voice-grade telephone lines from field offices to the Washington, D.C., Automatic Data Processing Unit (A.D.P. Unit). Such equipment would allow computer-processed data for current-purpose hydrologic data stations to be made available in a more timely manner. The specifications for the equipment were prepared in March 1970; invitations to bid were solicited, a contract was awarded and the equipment was delivered in November 1970. The equipment included two reader/transmitter units, and one receiver/recorder unit. The reader/transmitter units transmit manually entered fixed information, i.e. station number, beginning date and time, and ending date and time, and photoelectrically read and transmit the 16-channel paper tape data. The receiver/recorder unit records the transmitted information on IBM-compatible magnetic tape. This report summarizes the information gained from a year of pilot operation of the equipment, with and without a computer terminal at the field level, and makes recommendations for establishing a data-transmission system in the Water Resources Division.

  18. Multi-speed transmission

    SciTech Connect

    Ashikawa, N.; Nakayama, H.; Sumi, M.

    1986-12-02

    This patent describes a multi-speed transmission having forward speed gear trains and at least one reverse speed gear train, comprising, a pair of parallel fork shafts, one the shaft being fixed, the other the shaft being slidable along its axial direction, means to selectively engage the gear trains and means to retain the selective engagement means in the selected position. The means selectively engages the gear trains including a first shift fork connected to the fixed fork shaft so as to slide to either side of its disengaged neutral position, a second shift fork connected to the slideable fork shaft so as to slide to either side of its disengaged neutral position, and a third shift fork connected to the slidable fork shaft so as to slide in one direction by motion of the slideable fork shaft to only one side of its disengaged neutral position. Also included is a reverse shift fork connected to the slideable fork shaft and adapted to be actuated by motion of the slideable fork shaft in a direction opposite to the direction of the motion which engages the third shift fork.

  19. Electronically controlled automatic transmission

    SciTech Connect

    Ohkubo, M.; Shiba, H.; Nakamura, K.

    1989-03-28

    This patent describes an electronically controlled automatic transmission having a manual valve working in connection with a manual shift lever, shift valves operated by solenoid valves which are driven by an electronic control circuit previously memorizing shift patterns, and a hydraulic circuit controlled by these manual valve and shift valves for driving brakes and a clutch in order to change speed. Shift patterns of 2-range and L-range, in addition to a shift pattern of D-range, are memorized previously in the electronic control circuit, an operation switch is provided which changes the shift pattern of the electronic control circuit to any shift pattern among those of D-range, 2-range and L-range at time of the manual shift lever being in a D-range position, a releasable lock mechanism is provided which prevents the manual shift lever from entering 2-range and L-range positions, and the hydraulic circuit is set to a third speed mode when the manual shift lever is in the D-range position. The circuit is set to a second speed mode when it is in the 2-range position, and the circuit is set to a first speed mode when it is in the L-range position, respectively, in case where the shift valves are not working.

  20. Energy Corner: Heat Reclamation Rescues Wasted Heat.

    ERIC Educational Resources Information Center

    Daugherty, Thomas

    1982-01-01

    Heat reclamation systems added to pre-existing central heating systems provide maximum savings at minimum cost. The benefits of a particular appliance marketed under the brand name "Energizer" are discussed. (Author/MLF)

  1. Energy Corner: Heat Reclamation Rescues Wasted Heat.

    ERIC Educational Resources Information Center

    Daugherty, Thomas

    1982-01-01

    Heat reclamation systems added to pre-existing central heating systems provide maximum savings at minimum cost. The benefits of a particular appliance marketed under the brand name "Energizer" are discussed. (Author/MLF)

  2. Mass transfer effects on the transmission of bubble screens

    NASA Astrophysics Data System (ADS)

    Fuster, Daniel; Bergamasco, Luca

    2016-11-01

    In this work we investigate, theoretically and numerically, the reflection and transmission properties of bubble screens excited by pressure wave pulses. We use modified expressions for the bubble resonance frequency and the damping factor in order to capture the influence of mass transfer on the reflection-transmission coefficients. In addition to the influence of variables such as the bubble radius and the averaged inter-bubble distance, the analysis reveals that in conditions close to the saturation line there exists a regime where the heat transport surrounding the bubble plays an important role on the bubble's response also influencing the reflection properties of the bubble screen. The linear analysis allows us to predict the critical vapor content beyond which liquid heat's transport controls the dynamic response of the bubbles. Numerical simulations show that these effects become especially relevant in the nonlinear regime. ANR Cachmap.

  3. Direct current power transmission systems

    SciTech Connect

    Padiyar, K.R.

    1991-01-01

    This book represents text on HVDC transmission available. It deals with the various aspects of the state of the art in HVDC transmission technology. This book presents many aspects of interactions of AC/DC systems. Modeling and analysis of DC systems are also discussed in detail.

  4. Hendra virus ecology and transmission.

    PubMed

    Field, Hume E

    2016-02-01

    Hendra virus causes acute and highly fatal infection in horses and humans. Pteropid bats (flying-foxes) are the natural host of the virus, with age and species being risk factors for infection. Urine is the primary route of excretion in flying-foxes, with viral RNA more frequently detected in Pteropus alecto and P. conspicillatus than other species. Infection prevalence in flying-foxes can vary between and within years, with a winter peak of excretion occurring in some regions. Vertical transmission and recrudescing infection has been reported in flying-foxes, but horizontal transmission is evidently the primary mode of transmission. The most parsimonious mode of flying-fox to horse transmission is equine contact (oro-nasal, conjunctival) with infected flying-fox urine, either directly, or via urine-contaminated pasture or surfaces. Horse to horse transmission is inefficient, requiring direct contact with infected body fluids. Flying-fox to human transmission has not been recorded; all human cases have been associated with close and direct contact with infected horses. Canine cases (subclinical) have also been limited to equine case properties. Notwithstanding the recent availability of an effective vaccine for horses, a comprehensive understanding of Hendra virus ecology and transmission is essential to limit inter-species transmission.

  5. A Quantitative Transmission Line Experiment

    ERIC Educational Resources Information Center

    Johnston, D. C.; Silbernagel, B. G.

    1969-01-01

    Describes modifications of a commercially available strip-type transmission line, which makes possible reproducible measurements of standing waves on the line. Experimental data yield values for the characteristic impedance, phase velocity and line wavelength of radiation in the transmission line, and the dielectric constant of material in the…

  6. Automatic transmission for motor vehicles

    SciTech Connect

    Miura, M.; Sakakibara, S.

    1989-06-27

    An automatic transmission for a motor vehicle is described, comprising: a transmission housing; a hydraulic torque converter having rotational axes, an input shaft, an output shaft and a direct coupling clutch for directly coupling the input shaft to the output shaft; an auxiliary transmission mechanism provided coaxially with the hydraulic torque converter and having an input shaft, an output shaft with an input end and an output end and an overdrive mechanism of planetary gear type having a reduction ratio smaller than 1, the input shaft and the output shaft of the auxiliary transmission being located close to and on the side of the hydraulic torque converter with respect to the auxiliary transmission, respectively, and being coupled with a planetary gear carrier and a ring gear of the overdrive mechanism, respectively, a one-way clutch being provided between the planetary gear carrier and a sun gear of the overdrive mechanism, a clutch being provided between the planetary gear carrier and a position radially and outwardly of the one-way clutch for engaging the disengaging the planetary carrier and the sun gear, a brake being provided between the transmission housing and the sun gear and positioned radially and outwardly of the clutch for controlling engagement of the sun gear with a stationary portion of the transmission housing, and the output end of the output shaft being disposed between the auxiliary transmission mechanism and the hydraulic torque converter.

  7. A Quantitative Transmission Line Experiment

    ERIC Educational Resources Information Center

    Johnston, D. C.; Silbernagel, B. G.

    1969-01-01

    Describes modifications of a commercially available strip-type transmission line, which makes possible reproducible measurements of standing waves on the line. Experimental data yield values for the characteristic impedance, phase velocity and line wavelength of radiation in the transmission line, and the dielectric constant of material in the…

  8. HVDC power transmission technology assessment

    SciTech Connect

    Hauth, R.L.; Tatro, P.J.; Railing, B.D.; Johnson, B.K.; Stewart, J.R.; Fink, J.L.

    1997-04-01

    The purpose of this study was to develop an assessment of the national utility system`s needs for electric transmission during the period 1995-2020 that could be met by future reduced-cost HVDC systems. The assessment was to include an economic evaluation of HVDC as a means for meeting those needs as well as a comparison with competing technologies such as ac transmission with and without Flexible AC Transmission System (FACTS) controllers. The role of force commutated dc converters was to be assumed where appropriate. The assessment begins by identifying the general needs for transmission in the U.S. in the context of a future deregulated power industry. The possible roles for direct current transmission are then postulated in terms of representative scenarios. A few of the scenarios are illustrated with the help of actual U.S. system examples. non-traditional applications as well as traditional applications such as long lines and asynchronous interconnections are discussed. The classical ``break-even distance`` concept for comparing HVDC and ac lines is used to assess the selected scenarios. The impact of reduced-cost converters is reflected in terms of the break-even distance. This report presents a comprehensive review of the functional benefits of HVDC transmission and updated cost data for both ac and dc system components. It also provides some provocative thoughts on how direct current transmission might be applied to better utilize and expand our nation`s increasingly stressed transmission assets.

  9. Absorption heat pump system

    DOEpatents

    Grossman, Gershon

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  10. Absorption heat pump system

    DOEpatents

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  11. Heat Wave Safety Checklist

    MedlinePlus

    ... heat has caused more deaths than all other weather events, including floods. A heat wave is a ... care for heat- related emergencies … ❏ Listen to local weather forecasts and stay aware of upcoming temperature changes. ❏ ...

  12. Extreme Heat Guidebook

    EPA Pesticide Factsheets

    The 'Climate Change and Extreme Heat: What You Can Do to Prepare' handbook explains the connection between climate change and extreme heat events, and outlines actions citizens can take to protect their health during extreme heat.

  13. Babies and heat rashes

    MedlinePlus

    Heat rashes and babies; Prickly heat rash; Red miliaria ... To avoid heat rash , keep your baby cool and dry during warm weather. Some helpful suggestions: During the hot season, dress your baby in lightweight, soft, cotton clothing. Cotton ...

  14. Nonlinear transmission line based electron beam driver

    SciTech Connect

    French, David M.; Hoff, Brad W.; Tang Wilkin; Heidger, Susan; Shiffler, Don; Allen-Flowers, Jordan

    2012-12-15

    Gated field emission cathodes can provide short electron pulses without the requirement of laser systems or cathode heating required by photoemission or thermionic cathodes. The large electric field requirement for field emission to take place can be achieved by using a high aspect ratio cathode with a large field enhancement factor which reduces the voltage requirement for emission. In this paper, a cathode gate driver based on the output pulse train from a nonlinear transmission line is experimentally demonstrated. The application of the pulse train to a tufted carbon fiber field emission cathode generates short electron pulses. The pulses are approximately 2 ns in duration with emission currents of several mA, and the train contains up to 6 pulses at a frequency of 100 MHz. Particle-in-cell simulation is used to predict the characteristic of the current pulse train generated from a single carbon fiber field emission cathode using the same technique.

  15. Solar Power Satellite Microwave Power Transmission System Description Executive Summary

    NASA Technical Reports Server (NTRS)

    Woodcock, G. R.

    1980-01-01

    The history of the concept of microwave power beaming to Earth is reviewed with emphasis on transmission frequency selection. Constraints on the system power level results from (1) required rejection of waste heat resulting from inefficiencies in the cover conversion of dc electric power to microwave power; (2) the rf power intensity in the ionosphere; and (3) the effect of sidelobe level on aperture illumination factors. Transmitter arrangement, the power distribution system, attitude control, subarrays, waveguides, and alignment are discussed.

  16. Regional Transmission Projects: Finding Solutions

    SciTech Connect

    The Keystone Center

    2005-06-15

    The Keystone Center convened and facilitated a year-long Dialogue on "Regional Transmission Projects: Finding Solutions" to develop recommendations that will help address the difficult and contentious issues related to expansions of regional electric transmission systems that are needed for reliable and economic transmission of power within and across regions. This effort brought together a cross-section of affected stakeholders and thought leaders to address the problem with the collective wisdom of their experience and interests. Transmission owners sat at the table with consumer advocates and environmental organizations. Representatives from regional transmission organizations exchanged ideas with state and federal regulators. Generation developers explored common interests with public power suppliers. Together, the Dialogue participants developed consensus solutions about how to begin unraveling some of the more intractable issues surrounding identification of need, allocation of costs, and reaching consensus on siting issues that can frustrate the development of regional transmission infrastructure. The recommendations fall into three broad categories: 1. Recommendations on appropriate institutional arrangements and processes for achieving regional consensus on the need for new or expanded transmission infrastructure 2. Recommendations on the process for siting of transmission lines 3. Recommendations on the tools needed to support regional planning, cost allocation, and siting efforts. List of Dialogue participants: List of Dialogue Participants: American Electric Power American Transmission Company American Wind Energy Association California ISO Calpine Corporation Cinergy Edison Electric Institute Environmental Defense Federal Energy Regulatory Commission Great River Energy International Transmission Company ISO-New England Iowa Public Utility Board Kanner & Associates Midwest ISO National Association of Regulatory Utility Commissioners National Association

  17. Energy Transmission and Infrastructure

    SciTech Connect

    Mathison, Jane

    2012-12-31

    The objective of Energy Transmission and Infrastructure Northern Ohio (OH) was to lay the conceptual and analytical foundation for an energy economy in northern Ohio that will: • improve the efficiency with which energy is used in the residential, commercial, industrial, agricultural, and transportation sectors for Oberlin, Ohio as a district-wide model for Congressional District OH-09; • identify the potential to deploy wind and solar technologies and the most effective configuration for the regional energy system (i.e., the ratio of distributed or centralized power generation); • analyze the potential within the district to utilize farm wastes to produce biofuels; • enhance long-term energy security by identifying ways to deploy local resources and building Ohio-based enterprises; • identify the policy, regulatory, and financial barriers impeding development of a new energy system; and • improve energy infrastructure within Congressional District OH-09. This objective of laying the foundation for a renewable energy system in Ohio was achieved through four primary areas of activity: 1. district-wide energy infrastructure assessments and alternative-energy transmission studies; 2. energy infrastructure improvement projects undertaken by American Municipal Power (AMP) affiliates in the northern Ohio communities of Elmore, Oak Harbor, and Wellington; 3. Oberlin, OH-area energy assessment initiatives; and 4. a district-wide conference held in September 2011 to disseminate year-one findings. The grant supported 17 research studies by leading energy, policy, and financial specialists, including studies on: current energy use in the district and the Oberlin area; regional potential for energy generation from renewable sources such as solar power, wind, and farm-waste; energy and transportation strategies for transitioning the City of Oberlin entirely to renewable resources and considering pedestrians, bicyclists, and public transportation as well as drivers

  18. Heat pump systems

    SciTech Connect

    Sauer, H.J.; Howell, R.H.

    1983-01-01

    This book was written as a reference and textbook on heat pumps. Economics, thermodynamics, heat transfer, design, selection, and operating practices are covered in detail. Specific methods, and solutions rather than broad generalizations are emphasized. Includes problems, bibliographies, and a subject index. For applied science collections in public, college and appropriate special libraries. Contents: Thermodynamics, Heat pump systems and applications. Heat pump components. Heating and cooling loads. Energy use determination. Reliability, maintenance, and service. Advances in heat pumps. Appendices. Index.

  19. Woven heat exchanger

    DOEpatents

    Piscitella, R.R.

    1984-07-16

    This invention relates to a heat exchanger for waste heat recovery from high temperature industrial exhaust streams. In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  20. Multi-ratio transmission

    SciTech Connect

    Polak, J.C.

    1987-07-14

    A preselected multi-ratio power transmission is described comprising: input means for transmitting drive forces; output means; first, second and third friction clutch means each selectively engageable with the input means for accepting drive forces. First input gear means drivingly connects with the first friction clutch means; second input gear means drivingly connects with the second friction clutch means; third input gear means drivingly connects with the third clutch means; first output gear means drivingly connects with the first input gear means; second output gear means drivingly connects with the first and second input gear means; third output means drivingly connects between the third input gear means and the output means; and one double-acting synchronizer clutch for selectively engaging the first output gear means with the output means and alternately the second output gear means with the output means. The first friction clutch means and the one double-acting synchronizer clutch cooperates during engagement to establish two forward drive ratios between the input and output means. The second friction clutch means and the one double-acting synchronizer clutch cooperates during engagement to establish two other forward drive ratios between the input and output means. The third friction clutch means is engageable to provide another forward drive ratio between the input means and the output means; and the one double-acting synchronizer clutch is relieved of transmitting drive forces during the engagement of the third friction clutch means and being manipulable for alternate connection with either the first output gear or the second output gear while the third friction clutch means is engaged.

  1. [Mentalization and attachment transmission].

    PubMed

    Böhmann, Johann; Fritsch, Sophia; Lück, Monika; Stumpe, Anna; Taubner, Svenja; Vesterling, Christina

    2014-01-01

    The present study was investigating the predictive role of maternal mentalizing and general as well as depressive symptom burden for attachment security at the end of the first year on a sample of 44 mother-child-dyads from a low-risk community study. Maternal mentalizing was assessed in a multidimensional way as Reflective Functioning (off-line) and Mind-Mindedness (on-line). The design was longitudinal measuring maternal Mind-Mindedness from a videotaped mother-child-play-interaction at the age of three months. General and depressive symptom burden was assessed using the SCL-90-R when the children were nine months old. Maternal attachment and Reflective-Functioning, using the Adult-Attachment-Interview, as well as children's attachment behavior, using the Strange-Situation-Test, were investigated at the age of twelve months. Secure maternal attachment was associated with higher Reflective Functioning, higher frequency of Mind-Mindedness and lower general and depressive symptom burden. A moderation-analysis showed a statistical trend (p = .08) that the interaction of the frequency of mind-related comments, general symptom severity and maternal attachment has a predictive value for infantile attachment security. Results can be tentatively interpreted that mothers with insecure attachment who had a lower general symptom burden and who related to their three-months old babies with a high frequency of mind-related-comments were more likely to have securely attached children. Thus, results may serve as a groundwork for projects aiming to prevent the transmission of insecure attachment by strengthening maternal Mind-Mindedness and working on the reduction of maternal general symptom burden.

  2. Transmission gearing arrangement

    SciTech Connect

    Klemen, D.

    1987-08-04

    A gearing arrangement is described for an automotive power transmission comprising: an input shaft and an output shaft; first, second, and third simple planetary gear sets. Each has a sun gear, a ring gear, and a planet gears meshing with the sun and the ring gears and rotatably supported on a planet carrier; means rigidly interconnecting the ring gear of the third gear set and the carrier of the second gear set; means rigidly interconnecting the ring gear of the second gear set and the carrier of the first gear set; means rigidly connecting the output shaft and the carrier of the third gear set; a first intermediate shaft rigidly interconnecting the sun gears of the second and the third gear sets for unitary rotation; a second intermediate shaft rigidly connected to the carrier of the second gear set; a third intermediate shaft continuously connected to the input shaft and to the sun gear of the first gear set; first, second, and third brake means operative to selectively brake rotation of the ring gears of the first, the second, and the third gear sets, respectively; a first rotating clutch selectively operable to connect the input shaft and the first intermediate shaft for unitary rotation; a second rotating clutch selectively operable to connect the input shaft and the second intermediate shaft for unitary rotation; a fourth simple planetary gear set including a sun gear and a ring gear and planet gears meshing with the sun and the ring gears and rotatably supported on a planet carrier; means rigidly connecting the sun gear of the fourth gear set to the third intermediate shaft; means rigidly connecting the ring gear of the fourth gear set to the carrier of the first gear set; and a fourth brake means selectively operable to brake the carrier of the fourth gear set. The nine forward ratios are obtainable while preserving a single transition shifting over the entire nine forward ratios.

  3. Multistate differential transmission

    SciTech Connect

    Whalen, B.L.

    1989-05-30

    This patent describes a multistate transmission suitable for a colinear configuration having a stationary housing and an input shaft and an output shaft comprising: a first pair of planetary gear trains comprising a first common ring gear having a torque reducing gear train consisting of a sun gear and a planetary gears connected by way of a carrier to the output shaft and a reversing planetary gear train consisting of a sun gear and planetary gears; a second pair of planetary a trains comprising a second common ring gear having a torque reducing gear train consisting of a sun gear and planetary gears connected by way of a carrier to the sun gear in the reversing planetary gear train in the first pair of planetary gear trains and a reversing planetary gear train consisting of a sun gear and planetary gears; carrier means connecting the sun gears in the first pair of planetary gear trains to the housing through a free wheeling clutch to provide for rotation in one direction only and to one side of a first operational clutch. The other side of the clutch is connected to the sun gear in the reversing planetary gear train in the first pair of planetary gear trains; means connecting the planetary gears in the reversing mechanism of the second pair of planetary gear trains to the housing through a second operational clutch and to one side of a third operational clutch. The other side of the third operational clutch is connected to the sun gear in the reversing planetary gear grain in the second pair of planetary gear trains.

  4. Transmission line matrix modelling of thermal injuries to skin.

    PubMed

    Aliouat Bellia, S; Saidane, A; Hamou, A; Benzohra, M; Saiter, J M

    2008-08-01

    A numerical model based on the transmission line matrix method is presented for the quantitative prediction of skin burn resulting from exposure of a specific region of human skin surface to a high temperature heat source. Transient temperatures were numerically estimated by Pennes' bioheat equation, and the damage function denoting the extent of burn was calculated using the Arrhenius assumptions for protein damage rate. A two-dimensional transmission line matrix model was used to predict the effects of exposure time and structure thicknesses on the transient temperature distribution and damage extent. Compared with other numerical sources the transmission line matrix results revealed good agreement, suggesting that this method may be an effective tool for the thermal diagnostic of burns.

  5. Heat dissipation in atomic-scale junctions.

    PubMed

    Lee, Woochul; Kim, Kyeongtae; Jeong, Wonho; Zotti, Linda Angela; Pauly, Fabian; Cuevas, Juan Carlos; Reddy, Pramod

    2013-06-13

    Atomic and single-molecule junctions represent the ultimate limit to the miniaturization of electrical circuits. They are also ideal platforms for testing quantum transport theories that are required to describe charge and energy transfer in novel functional nanometre-scale devices. Recent work has successfully probed electric and thermoelectric phenomena in atomic-scale junctions. However, heat dissipation and transport in atomic-scale devices remain poorly characterized owing to experimental challenges. Here we use custom-fabricated scanning probes with integrated nanoscale thermocouples to investigate heat dissipation in the electrodes of single-molecule ('molecular') junctions. We find that if the junctions have transmission characteristics that are strongly energy dependent, this heat dissipation is asymmetric--that is, unequal between the electrodes--and also dependent on both the bias polarity and the identity of the majority charge carriers (electrons versus holes). In contrast, junctions consisting of only a few gold atoms ('atomic junctions') whose transmission characteristics show weak energy dependence do not exhibit appreciable asymmetry. Our results unambiguously relate the electronic transmission characteristics of atomic-scale junctions to their heat dissipation properties, establishing a framework for understanding heat dissipation in a range of mesoscopic systems where transport is elastic--that is, without exchange of energy in the contact region. We anticipate that the techniques established here will enable the study of Peltier effects at the atomic scale, a field that has been barely explored experimentally despite interesting theoretical predictions. Furthermore, the experimental advances described here are also expected to enable the study of heat transport in atomic and molecular junctions--an important and challenging scientific and technological goal that has remained elusive.

  6. Regenerative adsorbent heat pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  7. 47 CFR 25.212 - Narrowband analog transmissions, digital transmissions, and video transmissions in the GSO Fixed...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... transmissions, and video transmissions in the GSO Fixed-Satellite Service. 25.212 Section 25.212... Technical Standards § 25.212 Narrowband analog transmissions, digital transmissions, and video transmissions... narrowband and/or wideband digital services, including digital video services, if the maximum input spectral...

  8. 47 CFR 25.212 - Narrowband analog transmissions, digital transmissions, and video transmissions in the GSO Fixed...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... transmissions, and video transmissions in the GSO Fixed-Satellite Service. 25.212 Section 25.212... Technical Standards § 25.212 Narrowband analog transmissions, digital transmissions, and video transmissions... narrowband and/or wideband digital services, including digital video services, if the maximum input spectral...

  9. NWCC Transmission Case Study III

    SciTech Connect

    Terry Allison, Steve Wiese

    2000-03-01

    OAK-B135 Transmission System Improvements for Wind Energy Development in the Upper Midwest and Great Plains: Opportunities and Obstacles. This case study set out to ascertain the validity of three assumptions from the perspectives of stakeholders involved in wind energy and transmission issues in the Upper Midwest and Great Plains. The assumptions, and the stakeholders' reactions to each, are summarized below: Assumption 1--Transmission system improvements would provide significant benefits to the electricity network and its customers. Respondents acknowledge the potential for overall system benefits in the form of reduced line losses, improved grid stability and reliability, and enhanced ability to conduct spot market transactions. They also agree that these benefits relate to specific regional needs. However, there is disagreement over the extent of other benefits such as efficiency gains and cost savings from reduced line losses. Further, environmental and community interest groups point out that none of these benefits are realized without significant financial, environmental and social costs. Assumption 2--The benefits of transmission improvements would be helpful, but not confined, to wind power. All respondents agree that wind energy could benefit from transmission system improvements. But they also acknowledge, reluctantly, in the case of environmental stakeholders, that the benefits of an improved transmission system cannot be limited to environmentally preferable forms of generation. Some environmental and community advocate respondents also feel that transmission system improvement projects can be avoided altogether through energy conservation and efficiency measures, and by substituting wind energy for fossil generation. Assumption 3--Transmission alliances among stakeholders within and external to the wind community can provide benefits in the public interest. The fractured, multi-jurisdictional governance of the regional transmission system, and the

  10. Tonic cholinergic inhibition of spinal mechanical transmission.

    PubMed

    Zhuo, M; Gebhart, G F

    1991-08-01

    The present study examined the role of spinal cholinergic modulation of spinal mechanical and thermal transmission. Intrathecal administration of the cholinergic muscarinic receptor antagonists atropine or scopolamine in awake rats produced a dose-dependent decrease in the nociceptive mechanical withdrawal threshold of the rat tail. Pirenzepine, a selective muscarinic receptor type 1 antagonist, produced a similar effect at greater doses while mecamylamine, a nicotinic receptor antagonist, was without effect. The nociceptive tail flick (TF) reflex evoked by noxious heating was unaffected by the above drugs. Intrathecal administration of the cholinesterase inhibitor physostigmine produced a rapid, reversible and significant increase in the mechanical withdrawal threshold; TF latency was increased slightly but not significantly. Intrathecal administration of morphine, carbachol or clonidine all produced dose-dependent increases in TF latency; morphine and carbachol, but not clonidine, also increased the mechanical withdrawal threshold significantly. Intrathecal pretreatment with atropine reversed carbachol-produced increases in TF latency and the mechanical withdrawal threshold but did not affect increases in TF latency produced by intrathecal morphine or clonidine. The morphine-produced increase in the mechanical withdrawal threshold, however, was shifted rightward in a parallel fashion by intrathecal pretreatment with atropine. Intrathecal pretreatment with yohimbine did not affect the inhibitory effect of carbachol on either TF latency or the mechanical withdrawal threshold. These results suggest that a tonic, endogenous cholinergic muscarinic influence in the spinal cord, independent of spinal adrenergic mechanisms, modulates spinal mechanical transmission.

  11. Household transmission of SARS, 2003

    PubMed Central

    Wilson-Clark, Samantha D.; Deeks, Shelley L.; Gournis, Effie; Hay, Karen; Bondy, Susan; Kennedy, Erin; Johnson, Ian; Rea, Elizabeth; Kuschak, Theodore; Green, Diane; Abbas, Zahid; Guarda, Brenda

    2006-01-01

    Background In the 2003 outbreak in Toronto (in Ontario, Canada) of severe acute respiratory syndrome (SARS), about 20% of cases resulted from household transmission. The purpose of our study was to determine characteristics associated with the transmission of SARS within households. Methods A retrospective cohort of SARS-affected households was studied to determine risk factors for household transmission. Questionnaires addressed characteristics of the index case, the household and behaviours among household members. Potential risk factors for secondary transmission of infection were assessed in regression models appropriate to the outcome (secondary cases) and nonindependence of household members. Results The 74 households that participated included 18 secondary cases and 158 uninfected household members in addition to the 74 index cases. The household secondary attack rate was 10.2% (95% confidence interval [CI] 6.7%–23.5%). There was a linear association between the time the index patient spent at home after symptom onset and the secondary attack rate. Infected health care workers who were index cases had lower rates of household transmission. Interpretation SARS transmission in households is complex and increases with the length of time an ill person spends at home. Risk of transmission was lower when the index case was a health care worker. Rapid case identification is the public health measure most useful in minimizing exposure in the home. PMID:17098951

  12. Biology of HIV Mucosal Transmission

    PubMed Central

    Wu, Li

    2008-01-01

    Purpose of review HIV-1 mucosal transmission plays a critical role in HIV-1 infection and AIDS pathogenesis. This review summarizes the latest advances in biological studies of HIV-1 mucosal transmission, highlighting the implications of these studies in the development of microbicides to prevent HIV-1 transmission. Recent findings New studies of initial HIV-1 infection using improved culture models updated the current view of mucosal transmission. Mechanistic studies enhanced our understanding of cell-cell transmission of HIV-1 mediated by the major target cells, including dendritic cells, CD4+ T cells, and macrophages. Increasing evidence indicated the significance of host factors and immune responses in HIV-1 mucosal infection and transmission. Summary Recent progress in HIV-1 mucosal infection and transmission enriches our knowledge of virus-host interactions and viral pathogenesis. Functional studies of HIV-1 interactions with host cells can provide new insights into the design of more effective approaches to combat HIV-1 infection and AIDS. PMID:18802490

  13. The evolution of transmission mode

    PubMed Central

    Forbes, Mark R.; Hauffe, Heidi C.; Kallio, Eva R.; Okamura, Beth; Sait, Steven M.

    2017-01-01

    This article reviews research on the evolutionary mechanisms leading to different transmission modes. Such modes are often under genetic control of the host or the pathogen, and often in conflict with each other via trade-offs. Transmission modes may vary among pathogen strains and among host populations. Evolutionary changes in transmission mode have been inferred through experimental and phylogenetic studies, including changes in transmission associated with host shifts and with evolution of the unusually complex life cycles of many parasites. Understanding the forces that determine the evolution of particular transmission modes presents a fascinating medley of problems for which there is a lack of good data and often a lack of conceptual understanding or appropriate methodologies. Our best information comes from studies that have been focused on the vertical versus horizontal transmission dichotomy. With other kinds of transitions, theoretical approaches combining epidemiology and population genetics are providing guidelines for determining when and how rapidly new transmission modes may evolve, but these are still in need of empirical investigation and application to particular cases. Obtaining such knowledge is a matter of urgency in relation to extant disease threats. This article is part of the themed issue ‘Opening the black box: re-examining the ecology and evolution of parasite transmission’. PMID:28289251

  14. Endoscopic transmission of Helicobacter pylori.

    PubMed

    Tytgat, G N

    1995-01-01

    The contamination of endoscopes and biopsy forceps with Helicobacter pylori occurs readily after endoscopic examination of H. pylori-positive patients. Unequivocal proof of iatrogenic transmission of the organism has been provided. Estimates for transmission frequency approximate to 4 per 1000 endoscopies when the infection rate in the endoscoped population is about 60%. Iatrogenic transmission has also been shown to be the cause of the so-called 'acute mucosal lesion' syndrome in Japan. Traditional cleaning and alcohol rinsing is insufficient to eliminate endoscope/forceps contamination. Only meticulous adherence to disinfection recommendations guarantees H. pylori elimination.

  15. Electrical transmission line diametrical retainer

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Sneddon, Cameron; Briscoe, Michael; Fox, Joe

    2004-12-14

    The invention is a mechanism for retaining an electrical transmission line. In one embodiment of the invention it is a system for retaining an electrical transmission line within down hole components. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string. The system also includes a coaxial cable running between the first and second end of a drill pipe, the coaxial cable having a conductive tube and a conductive core within it. The invention allows the electrical transmission line to with stand the tension and compression of drill pipe during routine drilling cycles.

  16. Midwest Transmission Workshop I Summary

    SciTech Connect

    Kevin Bryan

    2001-05-01

    OAK-B135 The meeting was opened with a review of the purposes of the workshop: (1) Present and discuss key studies and assessments of transmission upgrades, additions and related issues for the upper Midwest, including work that addresses the full range of views on these topics; (2) Understand the various transmission issues in the upper Midwest and discuss options for addressing the issues; and (3) Identify the decision makers and entities that need to play an active role if transmission issues are to be resolved, and agree on next steps for engaging these individuals and organizations through education, outreach, and information dissemination.

  17. Hidden hazards of HCV transmission.

    PubMed

    Pondé, Robério Amorim de Almeida

    2011-02-01

    Hepatitis C virus infection is a global health problem that has important epidemiological and clinical consequences. It has been well established that exposure to infected blood is the main risk factor for HCV transmission. However, in 20% of cases the agent transmission occurs by unknown route or in the presence of an unidentified source of infection. Understanding of the epidemiology of HCV is needed to help us define future control and preventive strategies. Herein, we discuss about diagnosis of HCV infection and hepatitis C surveillance in the context of its transmission.

  18. Load Distribution in Transmissions "Split"

    NASA Technical Reports Server (NTRS)

    Krantz, Timothy L.; Delgado, Irebert R.

    1998-01-01

    The transmission system of a helicopter must meet particularly critical requirements. It must transmit engine power to the rotor, at the same time ensuring a typical speed reduction of 60 to 1. It must also be safe, reliable, light, and reach a high level of performance while, at the same time, it must produce few vibrations and little noise. Helicopter transmissions have achieved high-level performances thanks to the combination of analyses, experiments, and the application of practical field experience. However, the new generation of helicopters will require transmission systems that are even safer, lighter, less noisy, and more reliable.

  19. The evolution of plant virus transmission pathways

    Treesearch

    Frédéric M. Hamelin; Linda J.S. Allen; Holly R. Prendeville; M. Reza Hajimorad; Michael J. Jeger

    2016-01-01

    The evolution of plant virus transmission pathways is studied through transmission via seed, pollen, oravector. We address the questions: under what circumstances does vector transmission make pollen transmission redundant? Can evolution lead to the coexistence of multiple virus transmission pathways? We restrict the analysis to an annual plant population in which...

  20. Intertwined arbovirus transmission activity: reassessing the transmission cycle paradigm

    PubMed Central

    Diaz, Luis A.; Flores, Fernando S.; Quaglia, Agustín; Contigiani, Marta S.

    2013-01-01

    Arboviruses are emerging/reemerging infectious agents worldwide. The factors within this scenario include vector and host population fluctuations, climatic changes, anthropogenic activities that disturb ecosystems, an increase in international flights, human mobility, and genetic mutations that allow spill-over phenomenon. Arboviruses are maintained by biologic transmission among vectors and hosts. Sometimes this biological transmission is specific and includes one vector and host species such as Chikungunya (CHIKV), Dengue (DENV), and urban Yellow Fever (YFV). However, most of the arboviruses are generalist and they use many vectors and hosts species. From this perspective, arboviruses are maintained through a transmission network rather than a transmission cycle. This allows us to understand the complexity and dynamics of the transmission and maintenance of arboviruses in the ecosystems. The old perspective that arboviruses are maintained in close and stable transmission cycles should be modified by a new more integrative and dynamic idea, representing the real scenario where biological interactions have a much broader representation, indicating the constant adaptability of the biological entities. PMID:23335900

  1. Odontoblast TRP channels and thermo/mechanical transmission.

    PubMed

    Son, A R; Yang, Y M; Hong, J H; Lee, S I; Shibukawa, Y; Shin, D M

    2009-11-01

    Odontoblasts function as mechanosensory receptors because of the expression of mechanosensitive channels in these cells. However, it is unclear if odontoblasts direct the signal transmission evoked by heat/cold or osmotic changes. This study investigated the effects of heat/cold or osmotic changes on calcium signaling and the functional expression of the thermo/mechanosensitive transient receptor potential (TRP) channels in primary cultured mouse odontoblastic cells, with the use of RT-PCR, fluorometric calcium imaging, and electrophysiology. TRPV1, TRPV2, TRPV3, TRPV4, and TRPM3 mRNA was expressed, but TRPM8 and TRPA1 mRNA was not. The receptor-specific stimulation of TRPV1-3 (heat-sensing receptors) and TRPV4/ TRPM3 (mechanic receptors) caused increases in the intracellular calcium concentration. Moreover, the channel activities of TRPV1-4 and TRPM3 were confirmed by a whole-cell patch-clamp technique. These results suggest that primary cultured mouse odontoblasts express heat/mechanosensitive TRP channels and play a role in the underlying mechanisms of thermo/mechanosensitive sensory transmission.

  2. Graphene oxide reduction by microwave heating

    SciTech Connect

    Longo, Angela; Carotenuto, Gianfranco

    2016-05-18

    The possibility to prepare thermal reduced graphene oxide (Tr-GO) colloidal suspensions by microwave heating of graphene oxide (GO) suspensions in N-methyl-2-pyrrolidone (NMP) has been investigated. According to transmission electron microscopy (TEM) and absorption and emission spectroscopy characterization, such a type of thermal reduction does not lead to graphene quantum dots formation because only mono-functional oxygen-containing groups are removed.

  3. Direct fired heat exchanger

    DOEpatents

    Reimann, Robert C.; Root, Richard A.

    1986-01-01

    A gas-to-liquid heat exchanger system which transfers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine, to a liquid, generally an absorbent solution. The heat exchanger system is in a counterflow fluid arrangement which creates a more efficient heat transfer.

  4. Rotary magnetic heat pump

    DOEpatents

    Kirol, Lance D.

    1988-01-01

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation.

  5. Solar Heating Equipment

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Solar Unlimited, Inc.'s suncatcher line includes a variety of solar arrays, derived from NASA's satellite program: water heating only, partial home heating, or water and whole house central heating. Solar Unlimited developed a set of vigorous requirements to avoid problems common to solar heating technologies.

  6. Woven heat exchanger

    DOEpatents

    Piscitella, Roger R.

    1987-01-01

    In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  7. Nature's Heat Exchangers.

    ERIC Educational Resources Information Center

    Barnes, George

    1991-01-01

    Discusses the heat-transfer systems of different animals. Systems include heat conduction into the ground, heat transferred by convection, heat exchange in lizards, fish and polar animals, the carotid rete system, electromagnetic radiation from animals and people, and plant and animal fiber optics. (MDH)

  8. Solar heat pump

    NASA Astrophysics Data System (ADS)

    Hermanson, R.

    Brief discussions of the major components of a solar powered, chemical ground source heat pump are presented. The components discussed are the solar collectors and the chemical heat storage battery. Sodium sulfide is the medium used for heat storage. Catalog information which provides a description of all of the heat pump systems is included.

  9. Nature's Heat Exchangers.

    ERIC Educational Resources Information Center

    Barnes, George

    1991-01-01

    Discusses the heat-transfer systems of different animals. Systems include heat conduction into the ground, heat transferred by convection, heat exchange in lizards, fish and polar animals, the carotid rete system, electromagnetic radiation from animals and people, and plant and animal fiber optics. (MDH)

  10. REACH. Heating Units.

    ERIC Educational Resources Information Center

    Stanfield, Carter; And Others

    As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized units in the area of heating. The instructional units focus on electric heating systems, gas heating systems, and oil burning systems. Each unit follows a typical format that includes a unit…

  11. REACH. Heating Units.

    ERIC Educational Resources Information Center

    Stanfield, Carter; And Others

    As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized units in the area of heating. The instructional units focus on electric heating systems, gas heating systems, and oil burning systems. Each unit follows a typical format that includes a unit…

  12. Woven heat exchanger

    DOEpatents

    Piscitella, Roger R.

    1987-05-05

    In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  13. Rotary magnetic heat pump

    DOEpatents

    Kirol, L.D.

    1987-02-11

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

  14. Transmission of Information: An Overview.

    ERIC Educational Resources Information Center

    Thoma, George R.

    1981-01-01

    Outlines the basic principles underlying the transmission of information, including analog and digital modulation, limitations to communications, configurations of communications networks, optical fiber cables, and earth satellites. Six references are cited. (FM)

  15. Automatic transmission for electric wheelchairs.

    PubMed

    Reswick, J B

    1985-07-01

    A new infinitely variable automatic transmission called the RESATRAN that automatically changes its speed ratio in response to load torque being transmitted is presented. A prototype has been built and tested on a conventional three-wheeled electric motor propelled wheelchair. It is shown theoretically that more than 50 percent reduction in power during hill climbing may be expected when a transmission-equipped wheelchair is compared to a direct-drive vehicle operating at the same voltage. It is suggested that with such a transmission, wheelchairs can use much smaller motors and associated electronic controls, while at the same time gaining in efficiency that results in longer operating distances for the same battery charge. Design details of the transmission and test results are presented. These results show a substantial reduction in operating current and increased distance of operation over a test course.

  16. Cultural transmission of civic attitudes.

    PubMed

    Miles-Touya, Daniel; Rossi, Máximo

    2016-01-01

    In this empirical paper we attempt to measure the separate influence on civic engagement of educational attainment and cultural transmission of civic attitudes. Unlike most of the previous empirical works on this issue, we are able to approximate the cultural transmission of civic attitudes. We observe that civic returns to education are overstated when the transmission of civic attitudes is ignored. Moreover, the transmission of civic attitudes significantly enhances civic involvement and reinforces civic returns to education. Our findings are in line with the proposals of civic virtue theorists or grass movements who suggest that citizenship education should be included in the compulsory school curricula since, if not, families or local communities will only transmit their particular view of the world.

  17. Transmission of Information: An Overview.

    ERIC Educational Resources Information Center

    Thoma, George R.

    1981-01-01

    Outlines the basic principles underlying the transmission of information, including analog and digital modulation, limitations to communications, configurations of communications networks, optical fiber cables, and earth satellites. Six references are cited. (FM)

  18. Light aircraft sound transmission study

    NASA Technical Reports Server (NTRS)

    Heitman, K.; Bernhard, R. J.

    1983-01-01

    The plausibility of using the two microphone sound intensity technique to study noise transmission into light aircraft was investigated. In addition, a simple model to predict the interior sound pressure level of the cabin was constructed.

  19. Modeling the Transmission of Sound.

    ERIC Educational Resources Information Center

    Palmer, David H.

    2003-01-01

    Introduces a functional model of sound transmission through solids and gases. Describes procedures of an activity to model how sound travels faster through solid materials than gases. Use dominoes to represent the particles of solids and gases. (KHR)

  20. Fomite transmission in head lice.

    PubMed

    Burkhart, Craig N; Burkhart, Craig G

    2007-06-01

    Control of various infestations requires an accurate understanding of transmission. After thousands of years of lice infestation, scientific documentation of indirect contact transmission has been substantiated. Lice can be transferred in the egg, instar, and adult stages. Lice have now been shown in the laboratory to be readily dislodged by air movements such as blow-drying one's hair, combing, and toweling. Moreover, passive transfer to adjoining fabric is also frequently observed. Louse transmission by fomites occurs more frequently than has been commonly believed. Close proximity suffices to increase the likeliness of a new infestation. Thus louse control measures should take account of fomite transmission and include screening of all individuals within an infested person's immediate circle of contact, laundering of everything within the infested individuals' bed or quarantining of such material for 10 days, thorough vacuuming of floors, carpets, upholstery, with a standard vacuum cleaner.

  1. Hybrid-Vehicle Transmission System

    NASA Technical Reports Server (NTRS)

    Lupo, G.; Dotti, G.

    1985-01-01

    Continuously-variable transmission system for hybrid vehicles couples internal-combustion engine and electric motor section, either individually or in parallel, to power vehicle wheels during steering and braking.

  2. Transmission series power flow control

    SciTech Connect

    Nelson, R.J.; Bian, J.; Williams, S.L.

    1995-01-01

    This paper presents the characteristics of two gate turn-off (GTO) thyristor voltage-sourced inverter based series power flow control devices, namely the Series Power Flow Controller (SPFC) and the Unified Power Flow Controller (UPFC). These devices represent series extensions of the STATCON, an inverter-based shunt device developed under a tailored collaboration by EPRI, TVA and the Westinghouse Science and Technology Center, which will soon be placed in service on the TVA 161kV transmission system for transmission voltage control. Operation of the SPFC and UPFC is illustrated through the use of easily-constructed circle diagrams on the P-Q plane. The circle diagrams provide the transmission planning engineer with a simple means to assess the performance of these devices on the transmission system. A concluding example illustrates that the UPFC provides a level of power now control which is unattainable with more conventional devices.

  3. Transmission series power flow control

    SciTech Connect

    Nelson, R.J.; Bian, J.; Williams, S.L.

    1994-12-31

    This paper presents the characteristics of two gate turn-off (GTO) thyristor voltage-sourced inverter-based series power flow control devices, namely the Series Power Flow Controller (SPFC) and the Unified Power Flow Controller (UPFC). These devices represent series extensions of the STATCON, an inverter-based shunt device developed under a tailored collaboration by EPRI, TVA and the Westinghouse Science and Technology Center, which will soon be placed in service on the TVA 161kV transmission system for transmission voltage control. Operation of the SPFC and UPFC is illustrated through the use of easily-constructed circle diagrams on the P-Q plane. The circle diagrams provide the transmission planning engineer with a simple means to assess the performance of these devices on the transmission system. A concluding example illustrates that the UPFC provides a level of power flow control which is unattainable with more conventional devices.

  4. Hybrid-Vehicle Transmission System

    NASA Technical Reports Server (NTRS)

    Lupo, G.; Dotti, G.

    1985-01-01

    Continuously-variable transmission system for hybrid vehicles couples internal-combustion engine and electric motor section, either individually or in parallel, to power vehicle wheels during steering and braking.

  5. Heat Pipe Planets

    NASA Technical Reports Server (NTRS)

    Moore, William B.; Simon, Justin I.; Webb, A. Alexander G.

    2014-01-01

    When volcanism dominates heat transport, a terrestrial body enters a heat-pipe mode, in which hot magma moves through the lithosphere in narrow channels. Even at high heat flow, a heat-pipe planet develops a thick, cold, downwards-advecting lithosphere dominated by (ultra-)mafic flows and contractional deformation at the surface. Heat-pipes are an important feature of terrestrial planets at high heat flow, as illustrated by Io. Evidence for their operation early in Earth's history suggests that all terrestrial bodies should experience an episode of heat-pipe cooling early in their histories.

  6. District heating/cooling feasibility study for Jamestown, New York

    SciTech Connect

    Oliker, I.; Buffa, W.; Harms, R.; Preston, E.

    1982-12-01

    The results of the District Heating/Cooling Feasibility Study for Jamestown, NY are presented. The heat source for the system is a power plant located within the city limits. Several options for the extraction of heat from the power plant are developed and heat balances are presented. The options are based on the development of a hot water district heating system. The geography and climate of the area are discussed and the primary potential district heat district is described. The heat load assessment was based on fuel consumption data collected from a sampling of various types of structures and operations. The methodology is presented in detail followed by the block-by-block results which include the heated floor space, the annual total fuel consumed, the annual fuel consumed for comfort use, and the peak heat rate demands. The heating fuel demand and consumption for most of the major industries in the city is presented. A transmission and distribution system is developed to deliver heat from the power plant to the district heating customers. The piping design is described and the proposed pipe routing for the primary district is presented. Cost estimates are presented for the different district heating options developed. The cost of heat from the Jamestown district heating system has been determined using the required revenue approach to determine the minimum rate the utility must charge for district heat in order to break even. An analysis has also been performed to determine the maximum allowable charge for district heat that would allow consumers to recover their retrofit expenses in a five year period.

  7. Diversified transmission multichannel detection system

    SciTech Connect

    Tournois, P.; Engelhard, P.

    1984-07-03

    A detection system for imaging by sonar or radar signals. The system associates diversified transmissions with an interferometric base. This base provides an angular channel formation means and each signal formed in this way is processed by matched filtering in a circuit containing copy signals characterizing the space coloring obtained by the diversified transmission means. The invention is particularly applicable to side or front looking detection sonars.

  8. Free-Space Power Transmission

    NASA Technical Reports Server (NTRS)

    1989-01-01

    NASA Lewis Research Center organized a workshop on technology availability for free-space power transmission (beam power). This document contains a collection of viewgraph presentations that describes the effort by academia, industry, and the national laboratories in the area of high-frequency, high-power technology applicable to free-space power transmission systems. The areas covered were rectenna technology, high-frequency, high-power generation (gyrotrons, solar pumped lasers, and free electron lasers), and antenna technology.

  9. Thulium-170 heat source

    DOEpatents

    Walter, Carl E.; Van Konynenburg, Richard; VanSant, James H.

    1992-01-01

    An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.

  10. Heat Treating Apparatus

    DOEpatents

    De Saro, Robert; Bateman, Willis

    2002-09-10

    Apparatus for heat treating a heat treatable material including a housing having an upper opening for receiving a heat treatable material at a first temperature, a lower opening, and a chamber therebetween for heating the heat treatable material to a second temperature higher than the first temperature as the heat treatable material moves through the chamber from the upper to the lower opening. A gas supply assembly is operatively engaged to the housing at the lower opening, and includes a source of gas, a gas delivery assembly for delivering the gas through a plurality of pathways into the housing in countercurrent flow to movement of the heat treatable material, whereby the heat treatable material passes through the lower opening at the second temperature, and a control assembly for controlling conditions within the chamber to enable the heat treatable material to reach the second temperature and pass through the lower opening at the second temperature as a heated material.

  11. Integrated heat pump system

    SciTech Connect

    Reedy, W.R.

    1988-03-01

    An integrated heat pump and hot water system is described that includes: a heat pump having an indoor heat exchanger and an outdoor heat exchanger that are selectively connected to the suction line and the discharge line respectively of a compressor by a flow reversing means, and to each other by a liquid line having an expansion device mounted therein, whereby heating and cooling is provided to an indoor comfort zone by cycling the flow reversing means, a refrigerant to water heat exchanger having a hot water flow circuit in heat transfer relation with a first refrigerant condensing circuit and a second refrigerant evaporating circuit, a connection mounted in the liquid between the indoor heat exchanger and the expansion device, control means for regulating the flow of refrigerant through the refrigerant to water heat exchanger to selectively transfer heat into and out of the hot water flow circuit.

  12. Advanced Rotorcraft Transmission (ART) program

    NASA Technical Reports Server (NTRS)

    Heath, Gregory F.; Bossler, Robert B., Jr.

    1993-01-01

    Work performed by the McDonnell Douglas Helicopter Company and Lucas Western, Inc. within the U.S. Army/NASA Advanced Rotorcraft Transmission (ART) Program is summarized. The design of a 5000 horsepower transmission for a next generation advanced attack helicopter is described. Government goals for the program were to define technology and detail design the ART to meet, as a minimum, a weight reduction of 25 percent, an internal noise reduction of 10 dB plus a mean-time-between-removal (MTBR) of 5000 hours compared to a state-of-the-art baseline transmission. The split-torque transmission developed using face gears achieved a 40 percent weight reduction, a 9.6 dB noise reduction and a 5270 hour MTBR in meeting or exceeding the above goals. Aircraft mission performance and cost improvements resulting from installation of the ART would include a 17 to 22 percent improvement in loss-exchange ratio during combat, a 22 percent improvement in mean-time-between-failure, a transmission acquisition cost savings of 23 percent of $165K, per unit, and an average transmission direct operating cost savings of 33 percent, or $24K per flight hour. Face gear tests performed successfully at NASA Lewis are summarized. Also, program results of advanced material tooth scoring tests, single tooth bending tests, Charpy impact energy tests, compact tension fracture toughness tests and tensile strength tests are summarized.

  13. Essays on electricity transmission investment and financial transmission rights

    NASA Astrophysics Data System (ADS)

    Shang, Wenzhuo

    The U.S. electric power industry has been going through fundamental restructuring and realignment since the 1990's. Many issues and problems have emerged during the transition, and both economists and engineers have been looking for the solutions fervently. In this dissertation, which consists primarily of three essays, we apply economics theory and techniques to the power industry and address two related issues, transmission investment and financial transmission rights (FTRs). The first essay takes the decentralized perspective and investigates the efficiency attribute of market-based transmission investment under perfect competition. We clarify, for the first time, the nature of the externality created by loop flows that causes transmission investment to be inefficient. Our findings have important implications for better understanding of transmission market design and creating incentives for efficient transmission investment. In the second essay, we define several rules for allocating transmission investment cost within the framework of cooperative game theory. These rules provide fair, stable or efficient cost allocations in theory and are good benchmarks against which the allocation mechanism in practice can be compared and improved upon. In the last essay, we make exploratory efforts in analyzing and assessing empirically the performance of the Midwest independent system operator (MISO) FTR auction market. We reveal some stylized facts about this young market and find that it is not efficient under the risk-neutrality assumption. We also point out and correct the drawbacks in previous related work and suggest about more complete empirical work in future. In all, this dissertation makes both theoretic and empirical analysis of the two hot issues related to the power industry and comes up with findings that have important implications for the development of this industry.

  14. Industrial heat exchangers

    SciTech Connect

    Hayes, A.J.; Liang, W.W.; Richlen, S.L.; Tabb, E.S.

    1985-01-01

    This book presents the papers given at a symposium on the use of heat exchangers in the industrial plants. Topics considered include the US DOE and GRI research programs, advanced fixed boundary heat exchanger technology, commercial heat exchanger applications, thermo-hydraulic performance of heat-transfer equipment, field tests, the corrosion of heat exchanger materials, economics, cost benefit analysis, payback, and advanced assembly and materials.

  15. Thermoelectric heat exchange element

    DOEpatents

    Callas, James J.; Taher, Mahmoud A.

    2007-08-14

    A thermoelectric heat exchange module includes a first substrate including a heat receptive side and a heat donative side and a series of undulatory pleats. The module may also include a thermoelectric material layer having a ZT value of 1.0 or more disposed on at least one of the heat receptive side and the heat donative side, and an electrical contact may be in electrical communication with the thermoelectric material layer.

  16. Fundamentals of heat measurement. [heat flux transducers

    NASA Technical Reports Server (NTRS)

    Gerashchenko, O. A.

    1979-01-01

    Various methods and devices for obtaining experimental data on heat flux density over wide ranges of temperature and pressure are examined. Laboratory tests and device fabrication details are supplemented by theoretical analyses of heat-conduction and thermoelectric effects, providing design guidelines and information relevant to further research and development. A theory defining the measure of correspondence between transducer signal and the measured heat flux is established for individual (isolated) heat flux transducers subject to space and time-dependent loading. An analysis of the properties of stacked (series-connected) transducers of various types (sandwich-type, plane, and spiral) is used to derive a similarity theory providing general governing relationships. The transducers examined are used in 36 types of derivative devices involving direct heat loss measurements, heat conduction studies, radiation pyrometry, calorimetry in medicine and industry and nuclear reactor dosimetry.

  17. Heat cascading regenerative sorption heat pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1995-01-01

    A simple heat cascading regenerative sorption heat pump process with rejected or waste heat from a higher temperature chemisorption circuit (HTCC) powering a lower temperature physisorption circuit (LTPC) which provides a 30% total improvement over simple regenerative physisorption compression heat pumps when ammonia is both the chemisorbate and physisorbate, and a total improvement of 50% or more for LTPC having two pressure stages. The HTCC contains ammonia and a chemisorbent therefor contained in a plurality of canisters, a condenser-evaporator-radiator system, and a heater, operatively connected together. The LTPC contains ammonia and a physisorbent therefor contained in a plurality of compressors, a condenser-evaporator-radiator system, operatively connected together. A closed heat transfer circuit (CHTC) is provided which contains a flowing heat transfer liquid (FHTL) in thermal communication with each canister and each compressor for cascading heat from the HTCC to the LTPC. Heat is regenerated within the LTPC by transferring heat from one compressor to another. In one embodiment the regeneration is performed by another CHTC containing another FHTL in thermal communication with each compressor. In another embodiment the HTCC powers a lower temperature ammonia water absorption circuit (LTAWAC) which contains a generator-absorber system containing the absorbent, and a condenser-evaporator-radiator system, operatively connected together. The absorbent is water or an absorbent aqueous solution. A CHTC is provided which contains a FHTL in thermal communication with the generator for cascading heat from the HTCC to the LTAWAC. Heat is regenerated within the LTAWAC by transferring heat from the generator to the absorber. The chemical composition of the chemisorbent is different than the chemical composition of the physisorbent, and the absorbent. The chemical composition of the FHTL is different than the chemisorbent, the physisorbent, the absorbent, and ammonia.

  18. Dynamic simulation for distortion image with turbulence atmospheric transmission effects

    NASA Astrophysics Data System (ADS)

    Du, Huijie; Fei, Jindong; Qing, Duzheng; Zhao, Hongming; Yu, Hong; Cheng, Chen

    2013-09-01

    The imaging through atmospheric turbulence is an inevitable problem encountered by infrared imaging sensors working in the turbulence atmospheric environment. Before light-rays enter the window of the imaging sensors, the atmospheric turbulence will randomly interfere with the transmission of the light waves came from the objects, causing the distribution of image intensity values on the focal plane to diffuse, the peak value to decrease, the image to get blurred, and the pixels to deviate, and making image identification very difficult. Owing to the fact of the long processing time and that the atmospheric turbulent flow field is unknown and hard to be described by mathematical models, dynamic simulation for distortion Image with turbulence atmospheric transmission effects is much more difficult and challenging in the world. This paper discusses the dynamic simulation for distortion Image of turbulence atmospheric transmission effect. First of all, with the data and the optical transmission model of the turbulence atmospheric, the ray-tracing method is applied to obtain the propagation path of optical ray which propagates through the high-speed turbulent flow field, and then to calculate the OPD from the reference wave to the reconverted wave front and obtain the point spread function (PSF). Secondly, infrared characteristics models of typical scene were established according to the theory of infrared physics and heat conduction, and then the dynamic infrared image was generated by OpenGL. The last step is to obtain the distortion Image with turbulence atmospheric transmission effects .With the data of atmospheric transmission computation, infrared simulation image of every frame was processed according to the theory of image processing and the real-time image simulation, and then the dynamic distortion simulation images with effects of blurring, jitter and shifting were obtained. Above-mentioned simulation method can provide the theoretical bases for recovering

  19. Heat pump augmentation of nuclear process heat

    SciTech Connect

    Koutz, S.L.

    1986-03-18

    A system is described for increasing the temperature of a working fluid heated by a nuclear reactor. The system consists of: a high temperature gas cooled nuclear reactor having a core and a primary cooling loop through which a coolant is circulated so as to undergo an increase in temperature, a closed secondary loop having a working fluid therein, the cooling and secondary loops having cooperative association with an intermediate heat exchanger adapted to effect transfer of heat from the coolant to the working fluid as the working fluid passes through the intermediate heat exchanger, a heat pump connected in the secondary loop and including a turbine and a compressor through which the working fluid passes so that the working fluid undergoes an increase in temperature as it passes through the compressor, a process loop including a process chamber adapted to receive a process fluid therein, the process chamber being connected in circuit with the secondary loop so as to receive the working fluid from the compressor and transfer heat from the working fluid to the process fluid, a heat exchanger for heating the working fluid connected to the process loop for receiving heat therefrom and for transferring heat to the secondary loop prior to the working fluid passing through the compressor, the secondary loop being operative to pass the working fluid from the process chamber to the turbine so as to effect driving relation thereof, a steam generator operatively associated with the secondary loop so as to receive the working fluid from the turbine, and a steam loop having a feedwater supply and connected in circuit with the steam generator so that feedwater passing through the steam loop is heated by the steam generator, the steam loop being connected in circuit with the process chamber and adapted to pass steam to the process chamber with the process fluid.

  20. Heat Pipe Technology

    NASA Astrophysics Data System (ADS)

    1981-01-01

    The heat pipe, a sealed chamber whose walls are lined with a "wick," a thin capillary network containing a working fluid in liquid form was developed for a heat distribution system for non-rotating satellites. Use of the heat pipe provides a continuous heat transfer mechanism. "Heat tubes" that improve temperature control in plastics manufacturing equipment incorporated the heat pipe technology. James M. Stewart, an independent consultant, patented the heat tubes he developed and granted a license to Kona Corporation. The Kona Nozzle for heaterless injection molding gets heat for its operation from an external source and has no internal heating bands, reducing machine maintenance and also eliminating electrical hazards associated with heater bands. The nozzles are used by Eastman Kodak, Bic Pen Corporation, Polaroid, Tupperware, Ford Motor Company, RCA, and Western Electric in the molding of their products.

  1. Enhancement of heat transfer

    NASA Astrophysics Data System (ADS)

    Nakayama, W.

    Recent publications on enhancement of heat transfer are reviewed, emphasizing the effects of roughness elements, fins, and porous surfaces. Enhancement of forced convective heat transfer on roughened surfaces, performance evaluation of enhanced surfaces, viscous flows in cooled tubes and tubes with swirlers, and active methods of enhancement are addressed. Aspects of pool boiling heat transfer are considered, including nucleate boiling heat transfer on rough surfaces and porous surfaces, and maximum and minimum heat fluxes. Evaporative heat transfer is discussed for thin-film evaporation on structured surfaces and liquid spray cooling of a heated surface. Condensation heat transfer on external surfaces is covered, including filmwise condensation on vertical finned and fluted surfaces and on horizontal tubes. In-tube boiling and condensation are treated, discussing their enhancement by fins and inserts, as well as critical heat flux in coiled, rifled, and corrugated tubes.

  2. Heat Pipe Technology

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The heat pipe, a sealed chamber whose walls are lined with a "wick," a thin capillary network containing a working fluid in liquid form was developed for a heat distribution system for non-rotating satellites. Use of the heat pipe provides a continuous heat transfer mechanism. "Heat tubes" that improve temperature control in plastics manufacturing equipment incorporated the heat pipe technology. James M. Stewart, an independent consultant, patented the heat tubes he developed and granted a license to Kona Corporation. The Kona Nozzle for heaterless injection molding gets heat for its operation from an external source and has no internal heating bands, reducing machine maintenance and also eliminating electrical hazards associated with heater bands. The nozzles are used by Eastman Kodak, Bic Pen Corporation, Polaroid, Tupperware, Ford Motor Company, RCA, and Western Electric in the molding of their products.

  3. Development of Heat-resistant XLPE Cable and Accessories

    NASA Astrophysics Data System (ADS)

    Yamada, Hiroyuki; Nakagawa, Shinichi; Murata, Yoshinao; Kishi, Kouji; Katakai, Shoshi

    We have developed heat-resistant XLPE cable and accessories that can be operated at 105°C as the maximum permissible conductor temperature in normal operation. Through this cable system, greater transmission capacity can be achieved using existing cable ducts and without increasing the conductor size of the cable. We have developed heat-resistant XLPE insulation material which has a higher melting point than that of conventional XLPE. The breakdown strength of heat-resistant XLPE cable at 105°C is almost the same as that of conventional XLPE cable at 90°C. The heat deformation of the new cable at 105°C is almost the same as that of conventional XLPE cable at 90°C. Conventional self-pressurized rubber joints can be applied to heat-resistant cable lines with the new waterproof joint compound with low heat resistivity.

  4. Radio frequency heating for in-situ remediation of DNAPL

    SciTech Connect

    Kasevich, R.S.

    1996-08-01

    In-situ radio frequency (RF) heating technology for treating soils contaminated with dense nonaqueous phase liquids (DNAPLs) is described. RF imparts heat to non-conducting materials through the application of carefully controlled RF transmissions, improving contaminant flow characteristics and facilitating separation and removal from subsurface soils. The paper outlines advantages and limitations of RF remediation, process operations, general technology considerations, low permeability media considerations, commercial availability, and costs. Two case histories of RF remediation are briefly summarized. 13 refs., 10 figs.

  5. Heterogeneity in schistosomiasis transmission dynamics.

    PubMed

    Mari, Lorenzo; Ciddio, Manuela; Casagrandi, Renato; Perez-Saez, Javier; Bertuzzo, Enrico; Rinaldo, Andrea; Sokolow, Susanne H; De Leo, Giulio A; Gatto, Marino

    2017-11-07

    Simple models of disease propagation often disregard the effects of transmission heterogeneity on the ecological and epidemiological dynamics associated with host-parasite interactions. However, for some diseases like schistosomiasis, a widespread parasitic infection caused by Schistosoma worms, accounting for heterogeneity is crucial to both characterize long-term dynamics and evaluate opportunities for disease control. Elaborating on the classic Macdonald model for macroparasite transmission, we analyze families of models including explicit descriptions of heterogeneity related to differential transmission risk within a community, water contact patterns, the distribution of the snail host population, human mobility, and the seasonal fluctuations of the environment. Through simple numerical examples, we show that heterogeneous multigroup communities may be more prone to schistosomiasis than homogeneous ones, that the availability of multiple water sources can hinder parasite transmission, and that both spatial and temporal heterogeneities may have nontrivial implications for disease endemicity. Finally, we discuss the implications of heterogeneity for disease control. Although focused on schistosomiasis, results from this study may apply as well to other parasitic infections with complex transmission cycles, such as cysticercosis, dracunculiasis and fasciolosis. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Heat transfer system

    DOEpatents

    Not Available

    1980-03-07

    A heat transfer system for a nuclear reactor is described. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  7. Heat transfer system

    DOEpatents

    McGuire, Joseph C.

    1982-01-01

    A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  8. Wound tube heat exchanger

    DOEpatents

    Ecker, Amir L.

    1983-01-01

    What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.

  9. Flexible Heating Head

    NASA Technical Reports Server (NTRS)

    Fox, Robert L.; Johnson, Samuel D.; Coultrip, Robert H.; Phillips, W. Morris

    1994-01-01

    United States Air Force is investigating method of repairing aircraft by use of adhesive bonding with induction heating to cure adhesive. Fast-acting and reliable induction heating device that is lightweight, portable, and easy to use needed for such applications. Newly developed flexible heating head lightweight and conforms to complex, curved surfaces. Incorporates principles and circuitry of toroid joining gun described in "Toroid Joining Gun for Fittings and Couplings" (LAR-14278). Concentrates heat in local area through induction heating. Flexible heating head contains tank circuit, connected via cable to source of power.

  10. Flexible Heating Head

    NASA Technical Reports Server (NTRS)

    Fox, Robert L.; Johnson, Samuel D.; Coultrip, Robert H.; Phillips, W. Morris

    1994-01-01

    United States Air Force is investigating method of repairing aircraft by use of adhesive bonding with induction heating to cure adhesive. Fast-acting and reliable induction heating device that is lightweight, portable, and easy to use needed for such applications. Newly developed flexible heating head lightweight and conforms to complex, curved surfaces. Incorporates principles and circuitry of toroid joining gun described in "Toroid Joining Gun for Fittings and Couplings" (LAR-14278). Concentrates heat in local area through induction heating. Flexible heating head contains tank circuit, connected via cable to source of power.

  11. Microscale Regenerative Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

    2006-01-01

    The device described herein is designed primarily for use as a regenerative heat exchanger in a miniature Stirling engine or Stirling-cycle heat pump. A regenerative heat exchanger (sometimes called, simply, a "regenerator" in the Stirling-engine art) is basically a thermal capacitor: Its role in the Stirling cycle is to alternately accept heat from, then deliver heat to, an oscillating flow of a working fluid between compression and expansion volumes, without introducing an excessive pressure drop. These volumes are at different temperatures, and conduction of heat between these volumes is undesirable because it reduces the energy-conversion efficiency of the Stirling cycle.

  12. Analysis of wafer heating in 14nm DUV layers

    NASA Astrophysics Data System (ADS)

    Subramany, Lokesh; Chung, Woong Jae; Samudrala, Pavan; Gao, Haiyong; Aung, Nyan; Gomez, Juan Manuel; Minghetti, Blandine; Lee, Shawn

    2016-03-01

    To further shrink the contact and trench dimensions, Negative Tone Development (NTD) has become the de facto process at these layers. The NTD process uses a positive tone resist and an organic solvent-based negative tone developer which leads to improved image contrast, larger process window and smaller Mask Error Enhancement Factor (MEEF)[1]. The NTD masks have high transmission values leading to lens heating and as observed here wafer heating as well. Both lens and wafer heating will contribute to overlay error, however the effects of lens heating can be mitigated by applying lens heating corrections while no such corrections exist for wafer heating yet. Although the magnitude of overlay error due to wafer heating is low relative to lens heating; ever tightening overlay requirements imply that the distortions due to wafer heating will quickly become a significant part of the overlay budget. In this work the effects, analysis and observations of wafer heating on contact and metal layers of the 14nm node are presented. On product wafers it manifests as a difference in the scan up and scan down signatures between layers. An experiment to further understand wafer heating is performed with a test reticle that is used to monitor scanner performance.

  13. In-volume heating using high-power laser diodes

    NASA Astrophysics Data System (ADS)

    Denisenkov, Valentin S.; Kiyko, Vadim V.; Vdovin, Gleb V.

    2015-03-01

    High-power lasers are useful instruments suitable for applications in various fields; the most common industrial applications include cutting and welding. We propose a new application of high-power laser diodes as in-bulk heating source for food industry. Current heating processes use surface heating with different approaches to make the heat distribution more uniform and the process more efficient. High-power lasers can in theory provide in-bulk heating which can sufficiently increase the uniformity of heat distribution thus making the process more efficient. We chose two media (vegetable fat and glucose) for feasibility experiments. First, we checked if the media have necessary absorption coefficients on the wavelengths of commercially available laser diodes (940-980 nm). This was done using spectrophotometer at 700-1100 nm which provided the dependences of transmission from the wavelength. The results indicate that vegetable fat has noticeable transmission dip around 925 nm and glucose has sufficient dip at 990 nm. Then, after the feasibility check, we did numerical simulation of the heat distribution in bulk using finite elements method. Based on the results, optimal laser wavelength and illuminator configuration were selected. Finally, we carried out several pilot experiments with high-power diodes heating the chosen media.

  14. Midwest Transmission Workshop III Summary

    SciTech Connect

    Kevin Bryan

    2003-03-12

    OAK-B135 On March 12-13, 2002, the National Wind Coordinating Committee (NWCC), in cooperation with regional stakeholders, held a two-day workshop: Planning for Electrical Transmission Needs in the Upper Midwest. The workshop was the outgrowth of an effort to develop a forum and process for consideration of transmission options that strives for equitable allocation of benefits and impacts among all affected parties. The goal of this workshop was to provide a catalyst for an enhanced, inclusive process for transmission planning with participation of and acceptance by all affected stakeholders. Participants in the meeting included representatives of state and regional regulatory agencies, utilities and power generators, the wind industry, environmental and landowner interests, and other interested parties (see Attachment A for a list of meeting participants).

  15. Clustering, climate and dengue transmission.

    PubMed

    Junxiong, Pang; Yee-Sin, Leo

    2015-06-01

    Dengue is currently the most rapidly spreading vector-borne disease, with an increasing burden over recent decades. Currently, neither a licensed vaccine nor an effective anti-viral therapy is available, and treatment largely remains supportive. Current vector control strategies to prevent and reduce dengue transmission are neither efficient nor sustainable as long-term interventions. Increased globalization and climate change have been reported to influence dengue transmission. In this article, we reviewed the non-climatic and climatic risk factors which facilitate dengue transmission. Sustainable and effective interventions to reduce the increasing threat from dengue would require the integration of these risk factors into current and future prevention strategies, including dengue vaccination, as well as the continuous support and commitment from the political and environmental stakeholders.

  16. Transmission lines emulating moving media

    NASA Astrophysics Data System (ADS)

    Vehmas, J.; Hrabar, S.; Tretyakov, S.

    2014-09-01

    In this paper, we show how the electromagnetic phenomena in moving magnetodielectric media can be emulated using artificial composite structures at rest. In particular, we introduce nonreciprocal periodically loaded transmission lines, which support waves obeying the same rules as plane electromagnetic waves in moving media. Because the actual physical structure is at rest, in these transmission lines there are no fundamental limitations on the velocity values, which may take values larger than the speed of light or even complex values (considering complex amplitudes in the time-harmonic regime). An example circuit of a unit cell of a ‘moving’ transmission line is presented and analyzed both numerically and experimentally. The special case of a composite right-/left- handed host line is also studied numerically. Besides the fundamental interest, the study is relevant for potential applications in realizing engineered materials for various transformations of electromagnetic fields.

  17. Remote control apparatus for transmission

    SciTech Connect

    Ebina, A.

    1989-01-10

    A remote control apparatus for a transmission is described, comprising: means for sending a signal representing an operation state of a change lever; auxiliary power means, remote-controlled by the change lever, for changing a gear position of the transmission and sending a signal representing the gear position; and control means for controlling an operation of the auxiliary power means in accordance with the change lever operation state signal and gear position signal, the control means being provided with neutral position holding means comprises signal transmission delay means. This comprises means for detecting that the shift path on which the striker presently exists is different from the shift path instructed according to the change lever operating signal, then detecting that the striker has reached the first neutral position according to the neutral position signal and generating a neutral position detection signal.

  18. Plasmodium vivax Transmission in Africa

    PubMed Central

    Howes, Rosalind E.; Reiner Jr., Robert C.; Battle, Katherine E.; Longbottom, Joshua; Mappin, Bonnie; Ordanovich, Dariya; Tatem, Andrew J.; Drakeley, Chris; Gething, Peter W.; Zimmerman, Peter A.; Smith, David L.; Hay, Simon I.

    2015-01-01

    Malaria in sub-Saharan Africa has historically been almost exclusively attributed to Plasmodium falciparum (Pf). Current diagnostic and surveillance systems in much of sub-Saharan Africa are not designed to identify or report non-Pf human malaria infections accurately, resulting in a dearth of routine epidemiological data about their significance. The high prevalence of Duffy negativity provided a rationale for excluding the possibility of Plasmodium vivax (Pv) transmission. However, review of varied evidence sources including traveller infections, community prevalence surveys, local clinical case reports, entomological and serological studies contradicts this viewpoint. Here, these data reports are weighted in a unified framework to reflect the strength of evidence of indigenous Pv transmission in terms of diagnostic specificity, size of individual reports and corroboration between evidence sources. Direct evidence was reported from 21 of the 47 malaria-endemic countries studied, while 42 countries were attributed with infections of visiting travellers. Overall, moderate to conclusive evidence of transmission was available from 18 countries, distributed across all parts of the continent. Approximately 86.6 million Duffy positive hosts were at risk of infection in Africa in 2015. Analysis of the mechanisms sustaining Pv transmission across this continent of low frequency of susceptible hosts found that reports of Pv prevalence were consistent with transmission being potentially limited to Duffy positive populations. Finally, reports of apparent Duffy-independent transmission are discussed. While Pv is evidently not a major malaria parasite across most of sub-Saharan Africa, the evidence presented here highlights its widespread low-level endemicity. An increased awareness of Pv as a potential malaria parasite, coupled with policy shifts towards species-specific diagnostics and reporting, will allow a robust assessment of the public health significance of Pv, as well

  19. Plasmodium vivax Transmission in Africa.

    PubMed

    Howes, Rosalind E; Reiner, Robert C; Battle, Katherine E; Longbottom, Joshua; Mappin, Bonnie; Ordanovich, Dariya; Tatem, Andrew J; Drakeley, Chris; Gething, Peter W; Zimmerman, Peter A; Smith, David L; Hay, Simon I

    2015-11-01

    Malaria in sub-Saharan Africa has historically been almost exclusively attributed to Plasmodium falciparum (Pf). Current diagnostic and surveillance systems in much of sub-Saharan Africa are not designed to identify or report non-Pf human malaria infections accurately, resulting in a dearth of routine epidemiological data about their significance. The high prevalence of Duffy negativity provided a rationale for excluding the possibility of Plasmodium vivax (Pv) transmission. However, review of varied evidence sources including traveller infections, community prevalence surveys, local clinical case reports, entomological and serological studies contradicts this viewpoint. Here, these data reports are weighted in a unified framework to reflect the strength of evidence of indigenous Pv transmission in terms of diagnostic specificity, size of individual reports and corroboration between evidence sources. Direct evidence was reported from 21 of the 47 malaria-endemic countries studied, while 42 countries were attributed with infections of visiting travellers. Overall, moderate to conclusive evidence of transmission was available from 18 countries, distributed across all parts of the continent. Approximately 86.6 million Duffy positive hosts were at risk of infection in Africa in 2015. Analysis of the mechanisms sustaining Pv transmission across this continent of low frequency of susceptible hosts found that reports of Pv prevalence were consistent with transmission being potentially limited to Duffy positive populations. Finally, reports of apparent Duffy-independent transmission are discussed. While Pv is evidently not a major malaria parasite across most of sub-Saharan Africa, the evidence presented here highlights its widespread low-level endemicity. An increased awareness of Pv as a potential malaria parasite, coupled with policy shifts towards species-specific diagnostics and reporting, will allow a robust assessment of the public health significance of Pv, as well

  20. Intercultural Transmission and Intergenerational Transmission in Immigrant Families.

    ERIC Educational Resources Information Center

    Nauck, Bernhard

    2001-01-01

    Examined the impact of intergenerational transmission processes on the intercultural contact and ethnic identification of second generation adolescents from five migrant groups in Germany, distinguishing four possible outcomes of intercultural contact (integration, assimilation, segregation, and marginalization). Data from interviews with same-sex…

  1. Electrical Transmission on the Lunar Surface. Part 1; DC Transmission

    NASA Technical Reports Server (NTRS)

    Gordon, Lloyd B.

    2001-01-01

    This report summarizes a portion of the results from a grant at Auburn University to study the electrical and thermal energy management for lunar facilities. Over the past year (June 1989 to May 1990) the following topics have been investigated: June 1989 to November 1989 - Literature survey, assessment of lunar power needs, and overview study of the requirements of a lunar power system; November 1989 to April 1990 - Develop models for the study of dc electrical power transmission lines for the lunar surface; March 1990 to May 1990 - Develop models for the study of ac electrical power transmission lines for the lunar surface. Because of the large amount of information in the model development and application to a wide parameter space this report is being bound separately. This report specifically contains the model development and parameter study for dc electrical power transmission lines. The end of the funding year (May 1990) will conclude with an annual report including the literature survey, the overview of the requirements of a lunar power system, and summaries of the dc and ac models of electrical transmission lines.

  2. Intercultural Transmission and Intergenerational Transmission in Immigrant Families.

    ERIC Educational Resources Information Center

    Nauck, Bernhard

    2001-01-01

    Examined the impact of intergenerational transmission processes on the intercultural contact and ethnic identification of second generation adolescents from five migrant groups in Germany, distinguishing four possible outcomes of intercultural contact (integration, assimilation, segregation, and marginalization). Data from interviews with same-sex…

  3. Equalization of data transmission cable

    NASA Technical Reports Server (NTRS)

    Zobrist, G. W.

    1975-01-01

    The paper describes an equalization approach utilizing a simple RLC network which can obtain a maximum slope of -12dB/octave for reshaping the frequency characteristics of a data transmission cable, so that data may be generated and detected at the receiver. An experimental procedure for determining equalizer design specifications using distortion analysis is presented. It was found that for lengths of 16 PEV-L cable of up to 5 miles and data transmission rates of up to 1 Mbs, the equalization scheme proposed here is sufficient for generation of the data with acceptable error rates.

  4. Power transmission line monitoring system

    SciTech Connect

    Seppa, T.O.

    1993-08-17

    A method for monitoring the sag of an overhead power transmission line comprising the steps of: measuring the tension of the power line; producing an electrical signal representative of the tension measurement; processing said electrical signal in accordance with a predetermined tension-sag relationship to produce a second signal which is a function of sag of the power line; transmitting said second electrical signal to a distant location in a predetermined transmission mode; receiving the second signal at the distant location whereby current in the power line is adjusted in accordance with the received second signal.

  5. Electromagnetic Transmission Through Resonant Structures

    NASA Astrophysics Data System (ADS)

    Young, Steven M.

    Electromagnetic resonators store energy in the form of oscillatory electric and magnetic fields and gradually exchange that energy by coupling with their environment. This coupling process can have profound effects on the transmission and reflection properties of nearby interfaces, with rapid transitions from high transmittance to high reflectance over narrow frequency ranges, and has been exploited to design useful optical components such as spectral filters and dielectric mirrors. This dissertation includes analytic, numeric, and experimental investigations of three different electromagnetic resonators, each based on a different method of confining electromagnetic fields near the region of interest. First, we show that a structure with two parallel conducting plates, each containing a subwavelength slit, supports a localized resonant mode bound to the slits and therefore exhibits (in the absence of nonradiative losses), perfect resonant transmission over a narrow frequency range. In practice, the transmission is limited by conduction losses in the sidewalls; nevertheless, experimental results at 10 GHz show a narrowband transmission enhancement by a factor of 104 compared to the non-resonant transmission, with quality factor (ratio of frequency to peak width) Q ~ 3000. Second, we describe a narrowband transmission filter based on a single-layer dielectric grating. We use a group theory analysis to show that, due to their symmetry, several of the grating modes cannot couple to light at normal incidence, while several others have extremely large coupling. We then show how selectively breaking the system symmetry using off-normal light incidence can produce transmission peaks by enabling weak coupling to some of the previously protected modes. The narrowband filtering capabilities are validated by an experimental demonstration in the long wavelength infrared, showing transmission peaks of quality factor Q ~ 100 within a free-spectral range of 8-15 mum. Third, we

  6. Transmission degradation and preservation for tapered optical fibers in rubidium vapor.

    PubMed

    Lai, Meimei; Franson, James D; Pittman, Todd B

    2013-04-20

    The use of subwavelength diameter tapered optical fibers (TOFs) in warm rubidium vapor has recently been identified as a promising system for realizing ultralow-power nonlinear optical effects. However, at the relatively high atomic densities needed for many of these experiments, rubidium atoms accumulating on the TOF surface can cause a significant loss of overall transmission through the fiber. Here we report direct measurements of the time scale associated with this transmission degradation for various rubidium density conditions. Transmission is affected almost immediately after the introduction of rubidium vapor into the system, and declines rapidly as the density is increased. More significantly, we show how a heating element designed to raise the TOF temperature can be used to reduce this transmission loss and dramatically extend the effective TOF transmission lifetime.

  7. 47 CFR 80.89 - Unauthorized transmissions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Unauthorized transmissions. 80.89 Section 80.89... transmissions. Stations must not: (a) Engage in superfluous radio-communication. (b) Use telephony on 243 MHz... transmission of distress, alarm, urgency, or safety signals or messages, or to test transmissions. (e)...

  8. 40 CFR 86.128-79 - Transmissions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Transmissions. 86.128-79 Section 86...-Duty Vehicles; Test Procedures § 86.128-79 Transmissions. (a) All test conditions, except as noted... automatic transmissions in “Drive” and the wheels braked; manual transmissions shall be in gear with...

  9. 47 CFR 80.89 - Unauthorized transmissions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Unauthorized transmissions. 80.89 Section 80.89... transmissions. Stations must not: (a) Engage in superfluous radio-communication. (b) Use telephony on 243 MHz... transmission of distress, alarm, urgency, or safety signals or messages, or to test transmissions. (e)...

  10. 40 CFR 86.128-79 - Transmissions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Transmissions. 86.128-79 Section 86...-Duty Vehicles; Test Procedures § 86.128-79 Transmissions. (a) All test conditions, except as noted... automatic transmissions in “Drive” and the wheels braked; manual transmissions shall be in gear with...

  11. 47 CFR 80.89 - Unauthorized transmissions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Unauthorized transmissions. 80.89 Section 80.89... transmissions. Stations must not: (a) Engage in superfluous radio-communication. (b) Use telephony on 243 MHz... transmission of distress, alarm, urgency, or safety signals or messages, or to test transmissions. (e)...

  12. 40 CFR 86.128-79 - Transmissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Transmissions. 86.128-79 Section 86...-Duty Vehicles; Test Procedures § 86.128-79 Transmissions. (a) All test conditions, except as noted... automatic transmissions in “Drive” and the wheels braked; manual transmissions shall be in gear with...

  13. 47 CFR 80.89 - Unauthorized transmissions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Unauthorized transmissions. 80.89 Section 80.89... transmissions. Stations must not: (a) Engage in superfluous radio-communication. (b) Use telephony on 243 MHz... transmission of distress, alarm, urgency, or safety signals or messages, or to test transmissions. (e)...

  14. Omega time transmissions and receiving requirements

    NASA Technical Reports Server (NTRS)

    Chi, A. R.; Fletcher, L. A.; Casselman, C. J.

    1971-01-01

    A short history is given of the development of dual VLF time transmission techniques. The theory of time recovery from the relative phase of the dual frequency transmission is presented. The transmission and receiving requirements for cycle identification and cycle ambiguity resolution are described. Finally, an experiment to test the capability of time transmission of the OMEGA system is proposed

  15. Radial heat flux transformer

    NASA Technical Reports Server (NTRS)

    Basiulis, A.; Buzzard, R. J.

    1971-01-01

    Unit moves heat radially from small diameter shell to larger diameter shell, or vice versa, with negligible temperature drop, making device useful wherever heating or cooling of concentrically arranged materials, substances, and structures is desired.

  16. Monogroove liquid heat exchanger

    NASA Technical Reports Server (NTRS)

    Brown, Richard F. (Inventor); Edelstein, Fred (Inventor)

    1990-01-01

    A liquid supply control is disclosed for a heat transfer system which transports heat by liquid-vapor phase change of a working fluid. An assembly (10) of monogroove heat pipe legs (15) can be operated automatically as either heat acquisition devices or heat discharge sources. The liquid channels (27) of the heat pipe legs (15) are connected to a reservoir (35) which is filled and drained by respective filling and draining valves (30, 32). Information from liquid level sensors (50, 51) on the reservoir (35) is combined (60) with temperature information (55) from the liquid heat exchanger (12) and temperature information (56) from the assembly vapor conduit (42) to regulate filling and draining of the reservoir (35), so that the reservoir (35) in turn serves the liquid supply/drain needs of the heat pipe legs (15), on demand, by passive capillary action (20, 28).

  17. An electrohydrodynamic heat pipe

    NASA Technical Reports Server (NTRS)

    Jones, T. B.

    1972-01-01

    Dielectric liquid for transfer of heat provides liquid flow from the condenser section to the evaporator section in conventional heat pipes. Working fluid is guided or pumped by an array of wire electrodes connected to a high-voltage source.

  18. Fusion heating technology

    SciTech Connect

    Cole, A.J.

    1982-06-01

    John Lawson established the criterion that in order to produce more energy from fusion than is necessary to heat the plasma and replenish the radiation losses, a minimum value for both the product of plasma density and confinement time t, and the temperature must be achieved. There are two types of plasma heating: neutral beam and electromagnetic wave heating. A neutral beam system is shown. Main development work on negative ion beamlines has focused on the difficult problem of the production of high current sources. The development of a 30 keV-1 ampere multisecond source module is close to being accomplished. In electromagnetic heating, the launcher, which provides the means of coupling the power to the plasma, is most important. The status of heating development is reviewed. Electron cyclotron resonance heating (ECRH), lower hybrid heating (HHH), and ion cyclotron resonance heating (ICRH) are reviewed.

  19. Cold Climate Heat Pump

    DTIC Science & Technology

    2013-08-01

    central heating , cooling, and air conditioning (HVAC) system . Both buildings had two zones for heating and cooling, which allowed for a direct...section calls for improved efficiency of mechanical systems as well as an increase of renewable resource usage. Current heating technologies in cold... heated refrigerant is injected into a mixing chamber between the two compressors. The injection leads to a gain in performance of the system through

  20. Compact, super heat exchanger

    NASA Technical Reports Server (NTRS)

    Fortini, A.; Kazaroff, J. M.

    1980-01-01

    Heat exchanger uses porous media to enhance heat transfer through walls of cooling channels, thereby lowering wall temperature. Porous media within cooling channel increases internal surface area from which heat can be transferred to coolant. Comparison data shows wall has lower temperature and coolant has higher temperature when porous medium is used within heat exchanger. Media can be sintered powedered metal, metal fibers, woven wire layers, or any porous metal having desired permeability and porosity.

  1. Compact, super heat exchanger

    NASA Technical Reports Server (NTRS)

    Fortini, A.; Kazaroff, J. M.

    1980-01-01

    Heat exchanger uses porous media to enhance heat transfer through walls of cooling channels, thereby lowering wall temperature. Porous media within cooling channel increases internal surface area from which heat can be transferred to coolant. Comparison data shows wall has lower temperature and coolant has higher temperature when porous medium is used within heat exchanger. Media can be sintered powedered metal, metal fibers, woven wire layers, or any porous metal having desired permeability and porosity.

  2. Solar heat receiver

    DOEpatents

    Hunt, A.J.; Hansen, L.J.; Evans, D.B.

    1982-09-29

    A receiver is described for converting solar energy to heat a gas to temperatures from 700 to 900/sup 0/C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  3. Solar heat receiver

    DOEpatents

    Hunt, Arlon J.; Hansen, Leif J.; Evans, David B.

    1985-01-01

    A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  4. Abrasion resistant heat pipe

    DOEpatents

    Ernst, D.M.

    1984-10-23

    A specially constructed heat pipe is described for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  5. Abrasion resistant heat pipe

    DOEpatents

    Ernst, Donald M.

    1984-10-23

    A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  6. Champagne Heat Pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    2004-01-01

    The term champagne heat pump denotes a developmental heat pump that exploits a cycle of absorption and desorption of carbon dioxide in an alcohol or other organic liquid. Whereas most heat pumps in common use in the United States are energized by mechanical compression, the champagne heat pump is energized by heating. The concept of heat pumps based on other absorption cycles energized by heat has been understood for years, but some of these heat pumps are outlawed in many areas because of the potential hazards posed by leakage of working fluids. For example, in the case of the water/ammonia cycle, there are potential hazards of toxicity and flammability. The organic-liquid/carbon dioxide absorption/desorption cycle of the champagne heat pump is similar to the water/ammonia cycle, but carbon dioxide is nontoxic and environmentally benign, and one can choose an alcohol or other organic liquid that is also relatively nontoxic and environmentally benign. Two candidate nonalcohol organic liquids are isobutyl acetate and amyl acetate. Although alcohols and many other organic liquids are flammable, they present little or no flammability hazard in the champagne heat pump because only the nonflammable carbon dioxide component of the refrigerant mixture is circulated to the evaporator and condenser heat exchangers, which are the only components of the heat pump in direct contact with air in habitable spaces.

  7. Liquid heat capacity lasers

    DOEpatents

    Comaskey, Brian J.; Scheibner, Karl F.; Ault, Earl R.

    2007-05-01

    The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.

  8. Heat pipes. [technology utilization

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The development and use of heat pipes are described, including space requirements and contributions. Controllable heat pipes, and designs for automatically maintaining a selected constant temperature, are discussed which would add to the versatility and usefulness of heat pipes in industrial processing, manufacture of integrated circuits, and in temperature stabilization of electronics.

  9. Heat-related illness.

    PubMed

    Atha, Walter F

    2013-11-01

    Environmental exposure to high temperatures can result in abnormalities ranging from mild heat exhaustion to heat stroke with multiorgan system failure. An understanding of the mechanisms of thermoregulation and how those mechanisms fail with extreme heat stress is critical for management of the patient with elevated body temperature in the emergency department.

  10. Heat Recovery System

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Ball Metal's design of ducting and controls for series of roof top heat exchangers was inspired by Tech Briefs. Heat exchangers are installed on eight press and coating lines used to decorate sheet metal. The heat recovery system provides an estimated energy savings of more than $250,000 per year.

  11. Liquid heat capacity lasers

    DOEpatents

    Comaskey, Brian J.; Scheibner, Karl F.; Ault, Earl R.

    2007-05-01

    The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.

  12. HEAT TRANSFER MEANS

    DOEpatents

    Fraas, A.P.; Wislicenus, G.F.

    1961-07-11

    A heat exchanger is adapted to unifomly cool a spherical surface. Equations for the design of a spherical heat exchanger hav~g tubes with a uniform center-to-center spining are given. The heat exchanger is illustrated in connection with a liquid-fueled reactor.

  13. Electric heating pad burns.

    PubMed

    Bill, T J; Edlich, R F; Himel, H N

    1994-01-01

    Patients with sensory deficits are especially prone to heating pad burns. Two cases are reported of patients with anesthetic skin who received partial and full-thickness burns of their feet from an electric heating pad. These burn injuries could have been prevented if the patients understood the potential hazard of heating pads.

  14. Orion Heat Shield

    NASA Image and Video Library

    2015-05-06

    ENGINEERS FROM AMES RESEARCH CENTER AND MARSHALL SPACE FLIGHT CENTER REMOVE AVCOAT SEGMENTS FROM THE SURFACE OF THE ORION HEAT SHIELD, THE PROTECTIVE SHELL DESIGNED TO HELP THE NEXT GENERATION CREW MODULE WITHSTAND THE HEAT OF ATMOSPHERIC REENTRY. THE HEAT SHIELD FLEW TO SPACE DURING THE EFT-1 FULL SCALL FLIGHT TEST OF ORION IN DECEMBER 2014

  15. Geothermal heat in a heat pump use

    NASA Astrophysics Data System (ADS)

    Pavlova, A.; Hansen, J.; Obermeyer, H.; Pavlova, I.

    2016-09-01

    The considered innovative technology proposes to use alternative energy sources for the process efficiency in low-height construction. The world economy depends on price rises for energy sources and the danger of environmental pollution increases. Geothermal energy is the basic resource saving and environmentally safe renewable heat source that is characterized by inexhaustibility, permanent all the-year-round use, universal prevalence of resources and the ability to replace considerable volumes of traditional energy carriers. The expediency and power efficiency to apply a heat pump with the use of geothermal heat is proved for low-height construction.

  16. Heat pipes for industrial waste heat recovery

    SciTech Connect

    Merrigan, M.A.

    1981-01-01

    Development work on the high temperature ceramic recuperator at Los Alamos National Laboratory is described and involved material investigations, fabrication methods development, compatibility tests, heat pipe operation, and the modeling of application conditions based on current industrial usage. Solid ceramic heat pipes, ceramic coated refractory pipes, and high-temperature oxide protected metallic pipes have been investigated. Economic studies of the use of heat-pipe based recuperators in industrial furnaces have been conducted and payback periods determined as a function of material, fabrication, and installation cost.

  17. High heat flux loop heat pipes

    NASA Technical Reports Server (NTRS)

    North, Mark T.; Sarraf, David B.; Rosenfeld, John H.; Maidanik, Yuri F.; Vershinin, Sergey

    1997-01-01

    Loop heat pipes (LHPs) can transport very large thermal power loads over long distances, through flexible, small diameter tubes against gravitational heads. In order to overcome the evaporator limit of LHPs, which is of about 0.07 MW/sq m, work was carried out to improve the efficiency by threefold to tenfold. The vapor passage geometry for the high heat flux conditions is shown. A bidisperse wick material within the circumferential vapor passages was used. Along with heat flux enhancement, several underlying issues were demonstrated, including the fabrication of bidisperse powder with controlled properties and the fabrication of a device geometry capable of replacing vapor passages with bidisperse powder.

  18. A corrosive resistant heat exchanger

    DOEpatents

    Richlen, S.L.

    1987-08-10

    A corrosive and erosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is pumped through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium. 3 figs., 3 tabs.

  19. Progressive transmission and compression images

    NASA Technical Reports Server (NTRS)

    Kiely, A. B.

    1996-01-01

    We describe an image data compression strategy featuring progressive transmission. The method exploits subband coding and arithmetic coding for compression. We analyze the Laplacian probability density, which closely approximates the statistics of individual subbands, to determine a strategy for ordering the compressed subband data in a way that improves rate-distortion performance. Results are presented for a test image.

  20. The transmission of oak wilt.

    Treesearch

    J.N. Gibbs; D.W. French

    1980-01-01

    Provides an up-to-date review of factors affecting the transmission of oak wilt, Ceratocystis fagacearum. Discusses the history and severity of the disease, the saprophytic existence of the fungus in the dying tree, seasonal susceptibility of trees to infection, overland and underground spread, the role of animals and insects as vectors or tree wounders, and the...

  1. Power superconducting power transmission cable

    DOEpatents

    Ashworth, Stephen P.

    2003-01-01

    The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

  2. Power superconducting power transmission cable

    DOEpatents

    Ashworth, Stephen P.

    2003-06-10

    The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

  3. Norovirus transmission on cruise ship.

    PubMed

    Isakbaeva, Elmira T; Widdowson, Marc-Alain; Beard, R Suzanne; Bulens, Sandra N; Mullins, James; Monroe, Stephan S; Bresee, Joseph; Sassano, Patricia; Cramer, Elaine H; Glass, Roger I

    2005-01-01

    An outbreak of norovirus gastroenteritis affected passengers on two consecutive cruises of ship X and continued on 4 subsequent cruises despite a 1-week sanitization. We documented transmission by food and person-to-person contact; persistence of virus despite sanitization onboard, including introductions of new strains; and seeding of an outbreak on land.

  4. Atlas Transmission Line Breakdown Analysis

    DTIC Science & Technology

    1999-06-01

    The Atlas facility will use 24 radially converging, vertically oriented and tapered, oil insulated, triplate transmission lines between the Marx ...taper from a height of 1.75 m at the Marx end to 0.32 m at the output end. The aluminum conductors, held together by 20 insulating spacers, are

  5. Tornadoes and transmission reliability planning

    SciTech Connect

    Teles, J.E.; Anderson, S.W.; Landgren, G.L.

    1980-01-01

    The objective of this paper is to introduce an analytical approach for predicting overhead transmission line outages that are caused by tornadoes. The method is presently being used to determine the effects of tornadoes on various right-of-way configurations associated with a generating station project or the supply to a major substation. 2 refs.

  6. Chemical heat pump

    DOEpatents

    Greiner, Leonard

    1980-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer. The heat pump part of the system heats or cools a house or other structure through a combination of evaporation and absorption or, conversely, condensation and desorption, in a pair of containers. A set of automatic controls change the system for operation during winter and summer months and for daytime and nighttime operation to satisfactorily heat and cool a house during an entire year. The absorber chamber is subjected to solar heating during regeneration cycles and is covered by one or more layers of glass or other transparent material. Daytime home air used for heating the home is passed at appropriate flow rates between the absorber container and the first transparent cover layer in heat transfer relationship in a manner that greatly reduce eddies and resultant heat loss from the absorbant surface to ambient atmosphere.

  7. A numerical study of EGS heat extraction process based on a thermal non-equilibrium model for heat transfer in subsurface porous heat reservoir

    NASA Astrophysics Data System (ADS)

    Chen, Jiliang; Jiang, Fangming

    2016-02-01

    With a previously developed numerical model, we perform a detailed study of the heat extraction process in enhanced or engineered geothermal system (EGS). This model takes the EGS subsurface heat reservoir as an equivalent porous medium while it considers local thermal non-equilibrium between the rock matrix and the fluid flowing in the fractured rock mass. The application of local thermal non-equilibrium model highlights the temperature-difference heat exchange process occurring in EGS reservoirs, enabling a better understanding of the involved heat extraction process. The simulation results unravel the mechanism of preferential flow or short-circuit flow forming in homogeneously fractured reservoirs of different permeability values. EGS performance, e.g. production temperature and lifetime, is found to be tightly related to the flow pattern in the reservoir. Thermal compensation from rocks surrounding the reservoir contributes little heat to the heat transmission fluid if the operation time of an EGS is shorter than 15 years. We find as well the local thermal equilibrium model generally overestimates EGS performance and for an EGS with better heat exchange conditions in the heat reservoir, the heat extraction process acts more like the local thermal equilibrium process.

  8. Radiant heat transfer of bicycle helmets and visors.

    PubMed

    Brühwiler, Paul A

    2008-08-01

    Twenty-six bicycle helmets and their associated visors were characterized for radiant heat transfer using a thermal manikin headform in a climate chamber to assess their ability to protect the wearer from heating by the sun. A single configuration for applied radiant flow of 9.3 W was used to assess the roles of the forward and upper vents and the visor. The helmets shielded 50-75% of the radiant heating without a visor and 65-85% with one. Twenty-three visors were shown to result in a relevant reduction of radiant heating of the face (>0.5 W), with 15 reaching approximately 1 W. Heating of the visor and/or helmet and subsequent heating of the air flowing into the helmet was nevertheless found to be a relevant effect in many cases, suggesting that simple measures like reflective upper surfaces could noticeably improve the radiant heat rejection without changing the helmet structure. The forward vents in the helmets that allow the transmission of radiant heat are often important for forced convection, so that minimizing radiant heating geneally reduces the maximization of forced convective heat loss for current helmets.

  9. Absorption heat pump system

    DOEpatents

    Grossman, Gershon; Perez-Blanco, Horacio

    1984-01-01

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  10. Urban heat island

    NASA Technical Reports Server (NTRS)

    Kim, Hongsuk H.

    1991-01-01

    The phenomenon of urban heat island was investigated by the use of LANDSAT Thematic Mapper data sets collected over the metropolitan area of Washington DC (U.S.). By combining the retrieved spectral albedos and temperatures, urban modification on radiation budgets of five surface categories were analyzed. The surface radiation budget imagery of the area show that urban heating is attributable to a large heat flux from the rapidly heating surfaces of asphalt, bare soil and short grass. In summer, symptoms of diurnal heating begin to appear by mid morning and can be about 10 degrees warmer than nearby woodlands in summer.

  11. Urban heat island

    NASA Technical Reports Server (NTRS)

    Kim, Hongsuk H.

    1991-01-01

    The phenomenon of urban heat island was investigated by the use of LANDSAT Thematic Mapper data sets collected over the metropolitan area of Washington DC (U.S.). By combining the retrieved spectral albedos and temperatures, urban modification on radiation budgets of five surface categories were analyzed. The surface radiation budget imagery of the area show that urban heating is attributable to a large heat flux from the rapidly heating surfaces of asphalt, bare soil and short grass. In summer, symptoms of diurnal heating begin to appear by mid morning and can be about 10 degrees warmer than nearby woodlands in summer.

  12. Practical heat treating

    SciTech Connect

    Boyer, H.E.

    1984-01-01

    This book presents the heat treating technology. Fundamental information is provided by first explaining briefly the principles of the heat treatment of steel and the concepts of hardness and hardenability. Next, consideration is given to furnaces and related equipment. The major portion of the book, however, is devoted to a discussion of the commonly used heat treatments for carbon and alloy steels, tool steels, stainless steels and cast irons. Sample treatments are given in detail for many of the commercially important and commonly specified grades. Chapters on case hardening procedures, flame and induction heating and the heat treating of non-ferrous alloys complete the book.

  13. "E" Heating Head

    NASA Technical Reports Server (NTRS)

    Fox, Robert L.; Swaim, Robert J.; Johnson, Samuel D.; Coultrip, Robert H.; Phillips, W. Morris; Copeland, Carl E.

    1994-01-01

    Two separate areas heated inductively for adhesive bonding in single operation. "E" heating head developed to satisfy need for fast-acting and reliable induction heating device. Used in attaching "high-hat" stiffeners to aircraft panels. Incorporates principles and circuitry of toroid joining gun. Width and length configured to provide variously sized heat zones, depending on bonding requirements. Lightweight, portable and provides rapid, reliable heating of dual areas in any environment. Well suited for flight-line and depot maintenance, and battlefield repair. Also useful in automotive assembly lines to strengthen automobile panels.

  14. Heat pipe investigations

    NASA Technical Reports Server (NTRS)

    Marshburn, J. P.

    1972-01-01

    The OAO-C spacecraft has three circular heat pipes, each of a different internal design, located in the space between the spacecraft structural tube and the experiment tube, which are designed to isothermalize the structure. Two of the pipes are used to transport high heat loads, and the third is for low heat loads. The test problems deal with the charging of the pipes, modifications, the mobile tilt table, the position indicator, and the heat input mechanisms. The final results showed that the techniques used were adequate for thermal-vacuum testing of heat pipes.

  15. "E" Heating Head

    NASA Technical Reports Server (NTRS)

    Fox, Robert L.; Swaim, Robert J.; Johnson, Samuel D.; Coultrip, Robert H.; Phillips, W. Morris; Copeland, Carl E.

    1994-01-01

    Two separate areas heated inductively for adhesive bonding in single operation. "E" heating head developed to satisfy need for fast-acting and reliable induction heating device. Used in attaching "high-hat" stiffeners to aircraft panels. Incorporates principles and circuitry of toroid joining gun. Width and length configured to provide variously sized heat zones, depending on bonding requirements. Lightweight, portable and provides rapid, reliable heating of dual areas in any environment. Well suited for flight-line and depot maintenance, and battlefield repair. Also useful in automotive assembly lines to strengthen automobile panels.

  16. Heat Rash (Prickly Heat or Miliaria)

    MedlinePlus

    ... dressed too warmly or has a fever. Tropical climates. Hot, humid weather can cause heat rash. Physical ... rash include: Age. Newborns are most susceptible. Tropical climates. People living in the tropics are far more ...

  17. Nonlinear transmission of an intense terahertz field through monolayer graphene

    SciTech Connect

    Hafez, H. A.; Ibrahim, A.; Ozaki, T.; Al-Naib, I.; Dignam, M. M.; Oguri, K.; Sekine, Y.; Hibino, H.; Cooke, D. G.; Tanaka, S.; Komori, F.

    2014-11-15

    We report nonlinear terahertz (THz) effects in monolayer graphene, giving rise to transmission enhancement of a single-cycle THz pulse when the incident THz peak electric field is increased. This transmission enhancement is attributed to reduced photoconductivity, due to saturation effects in the field-induced current and increased intraband scattering rates arising from transient heating of electrons. We have developed a tight-binding model of the response using the length gauge interaction Hamiltonian that provides good qualitative agreement. The model fully accounts for the nonlinear response arising from the linear dispersion energy spectrum in graphene. The results reveal a strong dependence of the scattering time on the THz field, which is at the heart of the observed nonlinear response.

  18. Broadband transmission spectroscopy in tissue: application to radiofrequency tissue fusion

    NASA Astrophysics Data System (ADS)

    Floume, Timmy; Syms, Richard R. A.; Darzi, Ara W.; Hanna, George B.

    2009-05-01

    Radiofrequency tissue fusion consists in heating apposed tissue faces, which results in their sealing. Tissue transformations must be controlled to obtain reliable reproducible seal. In this paper we demonstrate how to extract information on the two main tissue transformations, thermal damage and dehydration, from continuous wave transmission spectra. A fibre based near infrared transmission spectroscopy system is presented and described theoretically. Show demonstrate that such system can be fully modeled using ray optics considerations for the coupling of the light into optical fibers, and MC simulations of light propagation in tissue. We then develop an algorithm based on the absolute measurement of attenuation and the modified Beer Lambert Law that enables the extraction of absolute tissue hydration and information on the degree of thermal damage, via scattering losses. We also discuss the basis and limit of absolute measurement during broadband submicronic tissue transmittance spectroscopy.

  19. Transmission of electrons inside the cryogenic pumps of ITER injector

    SciTech Connect

    Veltri, P. Sartori, E.

    2016-02-15

    Large cryogenic pumps are installed in the vessel of large neutral beam injectors (NBIs) used to heat the plasma in nuclear fusion experiments. The operation of such pumps can be compromised by the presence of stray secondary electrons that are generated along the beam path. In this paper, we present a numerical model to analyze the propagation of the electrons inside the pump. The aim of the study is to quantify the power load on the active pump elements, via evaluation of the transmission probabilities across the domain of the pump. These are obtained starting from large datasets of particle trajectories, obtained by numerical means. The transmission probability of the electrons across the domain is calculated for the NBI of the ITER and for its prototype Megavolt ITer Injector and Concept Advancement (MITICA) and the results are discussed.

  20. The thermal performance of heat pipes with localized heat input

    NASA Technical Reports Server (NTRS)

    Cao, Yiding; Faghri, Amir; Mahefkey, E. T.

    1989-01-01

    The performance of heat pipes with localized heat input including the effects of axial and circumferential heat conduction under high and low working temperatures is investigated. The numerical results show that when heat pipes are spot heated, the peak temperature of the wall is greatly reduced and the surface can be protected from being burned out by the high heat flux. The boiling limitation becomes the most important limitation for this type of heat pipe. Numerical results for block heating a heat pipe with low working temperatures indicate a good agreement with existing experimental data. It is also shown that most of the input heat passes through the wall beneath the heated block.

  1. Flexible heating head for induction heating

    NASA Technical Reports Server (NTRS)

    Fox, Robert L. (Inventor); Johnson, Samuel D. (Inventor); Coultrip, Robert H. (Inventor); Phillips, W. Morris (Inventor)

    1993-01-01

    An induction heating head includes a length of wire having first and second opposite ends and being wound in a flat spiral shape to form an induction coil, a capacitor connected to the first and second ends of the wire, the induction coil and capacitor defining a tank circuit, and a flexible, elastomeric body molded to encase the induction coil. When a susceptor is placed in juxtaposition to the body, and the tank circuit is powered, the susceptor is inductively heated.

  2. Heat pipe cooling system with sensible heat sink

    NASA Technical Reports Server (NTRS)

    Silverstein, Calvin C.

    1988-01-01

    A heat pipe cooling system which employs a sensible heat sink is discussed. With this type of system, incident aerodynamic heat is transported via a heat pipe from the stagnation region to the heat sink and absorbed by raising the temperature of the heat sink material. The use of a sensible heat sink can be advantageous for situations where the total mission heat load is limited, as it is during re-entry, and a suitable radiation sink is not available.

  3. Heat pump apparatus

    DOEpatents

    Nelson, Paul A.; Horowitz, Jeffrey S.

    1983-01-01

    A heat pump apparatus including a compact arrangement of individual tubular reactors containing hydride-dehydride beds in opposite end sections, each pair of beds in each reactor being operable by sequential and coordinated treatment with a plurality of heat transfer fluids in a plurality of processing stages, and first and second valves located adjacent the reactor end sections with rotatable members having multiple ports and associated portions for separating the hydride beds at each of the end sections into groups and for simultaneously directing a plurality of heat transfer fluids to the different groups. As heat is being generated by a group of beds, others are being regenerated so that heat is continuously available for space heating. As each of the processing stages is completed for a hydride bed or group of beds, each valve member is rotated causing the heat transfer fluid for the heat processing stage to be directed to that bed or group of beds. Each of the end sections are arranged to form a closed perimeter and the valve member may be rotated repeatedly about the perimeter to provide a continuous operation. Both valves are driven by a common motor to provide a coordinated treatment of beds in the same reactors. The heat pump apparatus is particularly suitable for the utilization of thermal energy supplied by solar collectors and concentrators but may be used with any source of heat, including a source of low-grade heat.

  4. Heat tube device

    NASA Technical Reports Server (NTRS)

    Khattar, Mukesh K. (Inventor)

    1990-01-01

    The present invention discloses a heat tube device through which a working fluid can be circulated to transfer heat to air in a conventional air conditioning system. The heat tube device is disposable about a conventional cooling coil of the air conditioning system and includes a plurality of substantially U-shaped tubes connected to a support structure. The support structure includes members for allowing the heat tube device to be readily positioned about the cooling coil. An actuatable adjustment device is connected to the U-shaped tubes for allowing, upon actuation thereof, for the heat tubes to be simultaneously rotated relative to the cooling coil for allowing the heat transfer from the heat tube device to air in the air conditioning system to be selectively varied.

  5. Nanofluid heat capacities

    NASA Astrophysics Data System (ADS)

    Starace, Anne K.; Gomez, Judith C.; Wang, Jun; Pradhan, Sulolit; Glatzmaier, Greg C.

    2011-12-01

    Significant increases in the heat capacity of heat transfer fluids are needed not only to reduce the costs of liquid heating and cooling processes, but also to bring clean energy producing technologies like concentrating solar power (CSP) to price parity with conventional energy generation. It has been postulated that nanofluids could have higher heat capacities than conventional fluids. In this work, nano- and micron-sized particles were added to five base fluids (poly-α olefin, mineral oil, ethylene glycol, a mixture of water and ethylene glycol, and calcium nitrate tetrahydrate), and the resulting heat capacities were measured and compared with those of the neat base fluids and the weighted average of the heat capacities of the components. The particles used were inert metals and metal oxides that did not undergo any phase transitions over the temperature range studied. In the nanofluids studied here, we found no increase in heat capacity upon the addition of the particles larger than the experimental error.

  6. Deployable Heat Pipe Radiator

    NASA Technical Reports Server (NTRS)

    Edelstein, F.

    1975-01-01

    A 1.2- by 1.8-m variable conductance heat pipe radiator was designed, built, and tested. The radiator has deployment capability and can passively control Freon-21 fluid loop temperatures under varying loads and environments. It consists of six grooved variable conductance heat pipes attached to a 0.032-in. aluminum panel. Heat is supplied to the radiator via a fluid header or a single-fluid flexible heat pipe header. The heat pipe header is an artery design that has a flexible section capable of bending up to 90 degrees. Radiator loads as high as 850 watts were successfully tested. Over a load variation of 200 watts, the outlet temperature of the Freon-21 fluid varied by 7 F. An alternate control system was also investigated which used a variable conductance heat pipe header attached to the heat pipe radiator panel.

  7. Miniature Heat Pipes

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Small Business Innovation Research contracts from Goddard Space Flight Center to Thermacore Inc. have fostered the company work on devices tagged "heat pipes" for space application. To control the extreme temperature ranges in space, heat pipes are important to spacecraft. The problem was to maintain an 8-watt central processing unit (CPU) at less than 90 C in a notebook computer using no power, with very little space available and without using forced convection. Thermacore's answer was in the design of a powder metal wick that transfers CPU heat from a tightly confined spot to an area near available air flow. The heat pipe technology permits a notebook computer to be operated in any position without loss of performance. Miniature heat pipe technology has successfully been applied, such as in Pentium Processor notebook computers. The company expects its heat pipes to accommodate desktop computers as well. Cellular phones, camcorders, and other hand-held electronics are forsible applications for heat pipes.

  8. Active microchannel heat exchanger

    DOEpatents

    Tonkovich, Anna Lee Y [Pasco, WA; Roberts, Gary L [West Richland, WA; Call, Charles J [Pasco, WA; Wegeng, Robert S [Richland, WA; Wang, Yong [Richland, WA

    2001-01-01

    The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The microchannel heat exchanger has (a) an exothermic reaction chamber; (b) an exhaust chamber; and (c) a heat exchanger chamber in thermal contact with the exhaust chamber, wherein (d) heat from the exothermic reaction chamber is convected by an exothermic reaction exhaust through the exhaust chamber and by conduction through a containment wall to the working fluid in the heat exchanger chamber thereby raising a temperature of the working fluid. The invention is particularly useful as a liquid fuel vaporizer and/or a steam generator for fuel cell power systems, and as a heat source for sustaining endothermic chemical reactions and initiating exothermic reactions.

  9. Ceramic heat recuperators for industrial heat recovery

    SciTech Connect

    Not Available

    1980-05-01

    Results are presented from a continuing program whose purpose is to demonstrate the technical and economic feasibility of using ceramic heat recuperators for industrial heat recovery. The information presented can be used by engineers in industry to evaluate their specific furnace applications and to estimate the technical requirements and economic benefits from the use of ceramic heat recuperators. Chapter 2 presents methods that can be used to estimate the amount of energy savings by recuperation. Chapter 3 gives a brief background in heat exchanger design theory so that the reader can understand the procedures involved in designing and sizing heat exchangers for a given application. The specific GTE core design and the recuperator fabrication, housing and installation are discussed in Chapter 4. The demonstration project results are presented in Chapter 5. Each demonstration is described and the results, economics and problem areas discussed. The Appendices provide details that will allow the engineer in industry to select a core, size a heat exchanger, calculate the performance, determine energy saved and estimate the economics of using a ceramic recuperator for a specific industrial application. (LCL)

  10. Gas storage and transmission systems

    SciTech Connect

    Creed, M.R.; Gilmour, R.B.

    1982-02-16

    According to this scheme, associated gas that has been liquefied on an offshore platform or barge and transported under pressure (to reduce cooling requirements) could be received by a land terminal for storage under atmospheric pressure and subsequent vaporization. The pressurized LNG, having a temperature above its ambient-pressure bubble point, passes from the carrier through a heat exchanger where it cools to its ambient-pressure liquefaction temperature; it then flows through a pressure-reduction valve before entering the storage tank. Meanwhile, LNG from the storage tank is pumped up to pipeline pressure and passed through a second heat exchanger for warming before entering the baseload vaporizer. A nitrogen refrigerant circuit acts as the heat-exchange medium between the two exchangers.

  11. Absorption heat pumps

    NASA Astrophysics Data System (ADS)

    Huhtinen, M.; Heikkilae, M.; Andersson, R.

    1987-03-01

    The aim of the study was to analyze the technical and economic feasibility of absorption heat pumps in Finland. The work was done as a case study: the technical and economic analyses have been carried out for six different cases, where in each the suitable size and type of the heat pump plant and the auxiliary components and connections were specified. The study also detailed the costs concerning the procurement, installation and test runs of the machinery, as well as the savings in energy costs incurred by the introduction of the plant. Conclusions were drawn of the economic viability of the applications studied. The following cases were analyzed: heat recovery from flue gases and productin of district heat in plants using peat, natural gas, and municipal wastes as a fuel. Heat recovery in the pulp and paper industry for the upgrading of pressure of secondary steam and for the heating of white liquor and combustion and drying the air. Heat recovery in a peat-fulled heat and power plant from flue gases that have been used for the drying of peat. According to the study, the absorption heat pump suits best to the production of district heat, when the heat source is the primary energy is steam produced by the boiler. Included in the flue as condensing is the purification of flue gases. Accordingly, benefit is gained on two levels in thick applications. In heat and power plants the use of absorption heat pumps is less economical, due to the fact that the steam used by the pump reduces the production of electricity, which is rated clearly higher than heat.

  12. 24 CFR 3280.506 - Heat loss/heat gain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Heat loss/heat gain. 3280.506... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat loss/heat gain shall be determined by methods outlined in...

  13. 24 CFR 3280.506 - Heat loss/heat gain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Heat loss/heat gain. 3280.506... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat loss/heat gain shall be determined by methods outlined in...

  14. Akranes and Borgarfjordur district heating system

    SciTech Connect

    Ragnarsson, A.; Hrolfsson, I.

    1998-12-01

    Akranes and Borgarnes are two towns in the western part of Iceland, about 100 km north of Reykjavik. Geothermal investigations for Akranes started as early as around 1950; but in spite of several attempts, a geothermal field, which could be utilized economically, was not found for a long period. After the increase in oil prices in the early 1970s, further studies were carried out. On the basis of the results of those studies, it was decided to build a combined district heating system for Akranes, Borgarnes, Hvanneyri (agricultural school) and some farms in the Borgarfjordur region. The water is piped from the hot spring Deildartunga, which is one of the largest hot springs in the world. Besides that, the system utilizes two wells at the farm Baer. The utilization of the hot spring makes the system different from most other district heating systems in Iceland, which are based on water from wells. Akranes and Borgarfjordur District Heating System was established in 1979. Before that time, space heating in this area was both by oil (93%) and electricity (7%). The system has now been split into three companies: one that is responsible for all the hot water production and transmission, and one district heating system for each of the two communities.

  15. Transmission and transmission control device for providing downshifting

    SciTech Connect

    Ito, H.; Akashi, T.

    1986-11-18

    This patent describes a transmission for a vehicle, comprising a transmission mechanism, and an automatic control device; the transmission mechanism comprising: an input shaft; an output shaft, a first on-off clutch; a second on-off clutch; a first one way clutch; a second one way clutch; a first gear train having a first reduction gear ratio; a second gear train having a second reduction gear ratio smaller than the first reduction gear ratio; a third gear train having a third reduction gear ratio smaller than the second reduction gear ratio; and a fourth gear train having a fourth reduction gear ratio smaller than the third reduction gear ratio. A first synchronizer connects the input shaft and the output shaft via a series connection of the first on-off clutch, the first one way clutch, and the first gear train when the first synchronizer is shifted to a first side of a neutral position thereof so as to transmit rotational power from the input shaft to the output shaft in a normal rotational direction at a first speed stage and which connects the input shaft and the output shaft via series connection of the first on-off clutch.

  16. The evolution of plant virus transmission pathways.

    PubMed

    Hamelin, Frédéric M; Allen, Linda J S; Prendeville, Holly R; Hajimorad, M Reza; Jeger, Michael J

    2016-05-07

    The evolution of plant virus transmission pathways is studied through transmission via seed, pollen, or a vector. We address the questions: under what circumstances does vector transmission make pollen transmission redundant? Can evolution lead to the coexistence of multiple virus transmission pathways? We restrict the analysis to an annual plant population in which reproduction through seed is obligatory. A semi-discrete model with pollen, seed, and vector transmission is formulated to investigate these questions. We assume vector and pollen transmission rates are frequency-dependent and density-dependent, respectively. An ecological stability analysis is performed for the semi-discrete model and used to inform an evolutionary study of trade-offs between pollen and seed versus vector transmission. Evolutionary dynamics critically depend on the shape of the trade-off functions. Assuming a trade-off between pollen and vector transmission, evolution either leads to an evolutionarily stable mix of pollen and vector transmission (concave trade-off) or there is evolutionary bi-stability (convex trade-off); the presence of pollen transmission may prevent evolution of vector transmission. Considering a trade-off between seed and vector transmission, evolutionary branching and the subsequent coexistence of pollen-borne and vector-borne strains is possible. This study contributes to the theory behind the diversity of plant-virus transmission patterns observed in nature.

  17. Transmission electron microscopy of electrospun GaN nanofibers

    NASA Astrophysics Data System (ADS)

    Robles-García, Joshua L.; Meléndez, Anamaris; Yates, Douglas; Santiago-Avilés, Jorge J.; Ramos, Idalia; Campo, Eva M.

    2011-06-01

    We have reported earlier progress in producing polycrystalline wurtzite-polymorph and photo-conductive GaN nanofibers by electrospinning. This paper shows grain stacking during heat treatment and suggests the need to understand nucleation and grain growth following electrospinning. Transmission Electron Microscopy (TEM) analysis of GaN shows brittle fibers, grain stacking, and unfinished grain nucleation. X-Ray Diffraction analysis confirmed dominant hexagonal 101-wurtzite preferential overall orientation and the incipient grains are of high crystalline quality as seen by high resolution TEM.

  18. Life cycle assessment of base-load heat sources for district heating system options

    SciTech Connect

    Ghafghazi, Saeed; Sowlati, T.; Sokhansanj, Shahabaddine; Melin, Staffan

    2011-03-01

    Purpose There has been an increased interest in utilizing renewable energy sources in district heating systems. District heating systems are centralized systems that provide heat for residential and commercial buildings in a community. While various renewable and conventional energy sources can be used in such systems, many stakeholders are interested in choosing the feasible option with the least environmental impacts. This paper evaluates and compares environmental burdens of alternative energy source options for the base load of a district heating center in Vancouver, British Columbia (BC) using the life cycle assessment method. The considered energy sources include natural gas, wood pellet, sewer heat, and ground heat. Methods The life cycle stages considered in the LCA model cover all stages from fuel production, fuel transmission/transportation, construction, operation, and finally demolition of the district heating system. The impact categories were analyzed based on the IMPACT 2002+ method. Results and discussion On a life-cycle basis, the global warming effect of renewable energy options were at least 200 kgeqCO2 less than that of the natural gas option per MWh of heat produced by the base load system. It was concluded that less than 25% of the upstream global warming impact associated with the wood pellet energy source option was due to transportation activities and about 50% of that was resulted from wood pellet production processes. In comparison with other energy options, the wood pellets option has higher impacts on respiratory of inorganics, terrestrial ecotoxicity, acidification, and nutrification categories. Among renewable options, the global warming impact of heat pump options in the studied case in Vancouver, BC, were lower than the wood pellet option due to BC's low carbon electricity generation profile. Ozone layer depletion and mineral extraction were the highest for the heat pump options due to extensive construction required for these

  19. Integrated self-cleaning window assembly for optical transmission in combustion environments

    DOEpatents

    Kass, Michael D [Oak Ridge, TN

    2007-07-24

    An integrated window design for optical transmission in combustion environments is described. The invention consists of an integrated optical window design that prevents and removes the accumulation of carbon-based particulate matter and gaseous hydrocarbons through a combination of heat and catalysis. These windows will enable established optical technologies to be applied to combustion environments and their exhaust systems.

  20. Vegetation clearance distances to prevent wildland fire caused damage to telecommunication and power transmission infrastructure (2)

    Treesearch

    B. W. Butler; T. Wallace; J. Hogge

    2015-01-01

    Towers and poles supporting power transmission and telecommunication lines have collapsed due to heating from wildland fires. Such occurrences have led to interruptions in power or communication in large municipal areas with associated social and political implications as well as increased immediate danger to humans. Vegetation clearance standards for overhead...

  1. Vegetation clearance distances to prevent wildland fire caused damage to telecommunication and power transmission infrastructure

    Treesearch

    B. W. Butler; J. Webb; J. Hogge; T. Wallace

    2015-01-01

    Towers and poles supporting power transmission and telecommunication lines have collapsed due to heating from wildland fires. Such occurrences have led to interruptions in power or communication in large municipal areas with associated social and political implications as well as increased immediate danger to humans. Unfortunately, no studies address the question of...

  2. Insights into heat transfer mechanisms of biased CNTs

    NASA Astrophysics Data System (ADS)

    Voskanian, Norvik; Olsson, Eva; Cumings, John

    There has been considerable interest in studying carbon nanotubes for thermal management applications and as components of electronic devices. For typical conductors, the electrical current results in temperature increase, but for the case of carbon nanotubes (CNTs) supported on SiN membranes, it has been shown that the traditional joule heating mechanisms are supplemented by remote heating of the substrate. Using a thermal imaging technique based on Transmission Electron Microscopy, we demonstrate further evidence of this remote heating mechanism which suggests a non-equilibrium state between the electron temperature and phonon temperature of the CNT. We quantify the amount of remote heating as a ratio, β, between the power dissipation directly in the SiN divide by the total power applied. We find that initially β is high, but at higher applied voltage bias, β decreases, presumably because more hot electrons are available to scatter off carbon optical phonons, producing an increasing amount of traditional Joule heating.

  3. Light bulb heat exchanger for magnetohydrodynamic generator applications - Preliminary evaluation

    NASA Technical Reports Server (NTRS)

    Smith, J. M.; Hwang, C. C.; Seikel, G. R.

    1974-01-01

    The light-bulb heat-exchanger concept is investigated as a possible means of using a combustion heat source to supply energy to an inert gas MHD power generator system. In this concept, combustion gases flow through a central passage which consists of a duct with transparent walls through which heat is transferred by radiation to a radiation receiver which in turn heats the inert gas by convection. The effects of combustion-gas emissivity, transparent-wall-transmissivity, radiation-receiver emissivity, and the use of fins in the inert gas coolant passage are studied. The results indicate that inert gas outlet temperatures of 2500 K are possible for combustion temperatures of 3200 K and that sufficient energy can be transferred from the combustion gas to reduce its temperature to approximately 2000 K. At this temperature more conventional heat exchangers can be used.

  4. Heat treating carbon nanofibers for optimal composite performance

    SciTech Connect

    Howe, Jane Y; Tibbetts, Gary G.; Kwag, C; Lake, Max L

    2006-01-01

    Partial graphitization of carbon nanofibers by high-temperature heat treatment can give improved composite properties. The intrinsic electrical conductivity of the bulk carbon nanofibers measured under compression is maximized by giving the fibers an initial heat treatment at 1500 C. Similarly, for carbon nanofiber/polypropylene composites containing up to 12 vol% fiber, initial fiber heat treatments near 1500 C give tensile modulus and strength superior even to composites made from fibers graphitized at 2900 C. However, optimum composite conductivity is obtained with a somewhat lower heat-treatment temperature, near 1300 C. Transmission electron microscopy (TEM) along with x-ray diffraction (XRD) explains these results, showing that heat treating the fibers alters the exterior planes from continuous, coaxial, and poorly crystallized to discontinuous nested conical crystallites inclined at about 25 to the fiber axis.

  5. Sound transmission through a high-temperature acoustic probe tube

    NASA Technical Reports Server (NTRS)

    Parrott, Tony L.; Zorumski, William E.

    1990-01-01

    An investigation was conducted of acoustic transmission through a tube subjected to an intense thermal gradient along its axis. The results are of interest in the interpretation of acoustic data from probe tube configurations designed to measure fluctuating pressures in high temperature environments. The measured transfer function across a localized heated region in the tube was compared to a computed transfer function based on a theoretical analysis of propagation through strong temperature gradients. Over the frequency range 0.4 kHz to 6.0 kHz, generally good agreement was obtained between the measured and calculated attenuation across the heated region with some discrepancy occurring at the attenuation minima. Agreement between measured and calculated phase difference was excellent to within the measurement resolution.

  6. Diode laser satellite systems for beamed power transmission

    NASA Technical Reports Server (NTRS)

    Williams, M. D.; Kwon, J. H.; Walker, G. H.; Humes, D. H.

    1990-01-01

    A power system composed of an orbiting laser satellite and a surface-based receiver/converter is described. Power is transmitted from the satellite to the receiver/converter by laser beam. The satellite components are: (1) solar collector; (2) blackbody; (3) photovoltaic cells; (4) heat radiators; (5) laser system; and (6) transmission optics. The receiver/converter components are: receiver dish; lenticular lens; photocells; and heat radiator. Although the system can be adapted to missions at many locations in the solar system, only two are examined here: powering a lunar habitat; and powering a lunar rover. Power system components are described and their masses, dimensions, operating powers, and temperatures, are estimated using known or feasible component capabilities. The critical technologies involved are discussed and other potential missions are mentioned.

  7. Sound transmission through a high-temperature acoustic probe tube

    NASA Technical Reports Server (NTRS)

    Parrott, Tony L.; Zorumski, William E.

    1990-01-01

    An investigation was conducted of acoustic transmission through a tube subjected to an intense thermal gradient along its axis. The results are of interest in the interpretation of acoustic data from probe tube configurations designed to measure fluctuating pressures in high temperature environments. The measured transfer function across a localized heated region in the tube was compared to a computed transfer function based on a theoretical analysis of propagation through strong temperature gradients. Over the frequency range 0.4 kHz to 6.0 kHz, generally good agreement was obtained between the measured and calculated attenuation across the heated region with some discrepancy occurring at the attenuation minima. Agreement between measured and calculated phase difference was excellent to within the measurement resolution.

  8. Transmission electron microscopy analysis of hydroxyapatite nanocrystals from cattle bones

    SciTech Connect

    Patel, Sangeeta; Wei, Shanghai; Han, Jie; Gao, Wei

    2015-11-15

    In this present study, hydroxyapatite which was obtained from cattle bones has been heat treated at temperature 400 °C and 600 °C. The microstructure after the treatment has been studied in detail using Transmission electron microscopy (TEM) and X-ray diffraction techniques. The TEM results indicate that natural bone consists of collagen and hydroxyapatite nano-crystals which are needle shaped. The heat treatment influences the crystallinity and growth of these hydroxyapatite nano-crystals known as ‘crystal maturation’ or ‘crystal ageing’. - Highlights: • Hydroxyapatite is obtained from cattle bones. • Material has been characterised using XRD and TEM. • Crystal growth and orientation has been studied in detail.

  9. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1983-01-01

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  10. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1977-01-01

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  11. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1983-06-21

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  12. Lunar base heat pump

    NASA Technical Reports Server (NTRS)

    Goldman, Jeffrey H.; Tetreault, R.; Fischbach, D.; Walker, D.

    1994-01-01

    A heat pump is a device which elevates the temperature of a heat flow by a means of an energy input. By doing this, the heat pump can cause heat to transfer faster from a warm region to a cool region, or it can cause heat to flow from a cool region to a warmer region. The second case is the one which finds vast commercial applications such as air conditioning, heating, and refrigeration. Aerospace applications of heat pumps include both cases. The NASA Johnson Space Center is currently developing a Life Support Systems Integration Facility (LSSIF, previously SIRF) to provide system-level integration, operational test experience, and performance data that will enable NASA to develop flight-certified hardware for future planetary missions. A high lift heat pump is a significant part of the TCS hardware development associated with the LSSIF. The high lift heat pump program discussed here is being performed in three phases. In Phase 1, the objective is to develop heat pump concepts for a lunar base, a lunar lander, and for a ground development unit for the SIRF. In Phase 2, the design of the SIRF ground test unit is being performed, including identification and evaluation of safety and reliability issues. In Phase 3, the SIRF unit will be manufactured, tested, and delivered to the NASA Johnson Space Center.

  13. Heat strain in cold.

    PubMed

    Rintamäki, Hannu; Rissanen, Sirkka

    2006-07-01

    In spite of increased environmental cold stress, heat strain is possible also in a cold environment. The body heat balance depends on three factors: environmental thermal conditions, metabolic heat production and thermal insulation of clothing and other protective garments. As physical exercise may increase metabolic heat production from rest values by ten times or even more, the required thermal insulation of clothing may vary accordingly. However, in most outdoor work, and often in indoor cold work, too, the thermal insulation of clothing is impractical, difficult or impossible to adjust according to the changes in physical activity. This is especially true with whole body covering garments like chemical protective clothing. As a result of this imbalance, heat strain may develop. In cold all the signs of heat strain (core temperature above 38 degrees C, warm or hot thermal sensations, increased cutaneous circulation and sweating) may not be present at the same time. Heat strain in cold may be whole body heat strain or related only to torso or core temperature. Together with heat strain in torso or body core, there can be at the same time even cold strain in peripheral parts and/or superficial layers of the body. In cold environment both the preservation of insulation and facilitation of heat loss are important. Development of clothing design is still needed to allow easy adjustments of thermal insulation.

  14. Optimization of Heat Exchangers

    SciTech Connect

    Ivan Catton

    2010-10-01

    The objective of this research is to develop tools to design and optimize heat exchangers (HE) and compact heat exchangers (CHE) for intermediate loop heat transport systems found in the very high temperature reator (VHTR) and other Generation IV designs by addressing heat transfer surface augmentation and conjugate modeling. To optimize heat exchanger, a fast running model must be created that will allow for multiple designs to be compared quickly. To model a heat exchanger, volume averaging theory, VAT, is used. VAT allows for the conservation of mass, momentum and energy to be solved for point by point in a 3 dimensional computer model of a heat exchanger. The end product of this project is a computer code that can predict an optimal configuration for a heat exchanger given only a few constraints (input fluids, size, cost, etc.). As VAT computer code can be used to model characteristics )pumping power, temperatures, and cost) of heat exchangers more quickly than traditional CFD or experiment, optimization of every geometric parameter simultaneously can be made. Using design of experiment, DOE and genetric algorithms, GE, to optimize the results of the computer code will improve heat exchanger disign.

  15. Silicon Heat Pipe Array

    NASA Technical Reports Server (NTRS)

    Yee, Karl Y.; Ganapathi, Gani B.; Sunada, Eric T.; Bae, Youngsam; Miller, Jennifer R.; Beinsford, Daniel F.

    2013-01-01

    Improved methods of heat dissipation are required for modern, high-power density electronic systems. As increased functionality is progressively compacted into decreasing volumes, this need will be exacerbated. High-performance chip power is predicted to increase monotonically and rapidly with time. Systems utilizing these chips are currently reliant upon decades of old cooling technology. Heat pipes offer a solution to this problem. Heat pipes are passive, self-contained, two-phase heat dissipation devices. Heat conducted into the device through a wick structure converts the working fluid into a vapor, which then releases the heat via condensation after being transported away from the heat source. Heat pipes have high thermal conductivities, are inexpensive, and have been utilized in previous space missions. However, the cylindrical geometry of commercial heat pipes is a poor fit to the planar geometries of microelectronic assemblies, the copper that commercial heat pipes are typically constructed of is a poor CTE (coefficient of thermal expansion) match to the semiconductor die utilized in these assemblies, and the functionality and reliability of heat pipes in general is strongly dependent on the orientation of the assembly with respect to the gravity vector. What is needed is a planar, semiconductor-based heat pipe array that can be used for cooling of generic MCM (multichip module) assemblies that can also function in all orientations. Such a structure would not only have applications in the cooling of space electronics, but would have commercial applications as well (e.g. cooling of microprocessors and high-power laser diodes). This technology is an improvement over existing heat pipe designs due to the finer porosity of the wick, which enhances capillary pumping pressure, resulting in greater effective thermal conductivity and performance in any orientation with respect to the gravity vector. In addition, it is constructed of silicon, and thus is better

  16. "Bottle-Brush" Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Tward, E.; Gatewood, J. R.

    1982-01-01

    Heat exchanger consists of a metal tube with wires extending inward from wall. Conduction of heat along wires improves heat transfer to gas or other filling. Fluid is heated throughout the cross section of tube. Suggested applications are refrigerators, heat engines, thermal instrumentation, and heat switches.

  17. Development of large rotorcraft transmissions

    NASA Technical Reports Server (NTRS)

    Samanich, N. E.; Drago, R. J.; Mack, J. C.

    1984-01-01

    The U.S. Army Heavy Lift Helicopter (HLH) represents a large rotorcraft which was developed by an American aerospace company. In the early 1970's with the HLH Advanced Technology Components (ATC) program, the development of large rotorcraft transmission and drive systems was started. Failures in the spiral bevel gearing were experienced in tests because the employed method of analysis had not considered the effect of rim bending. Consequently, new gears with strengthened rims were designed and fabricated. For a more accurate prediction of the load capacity of the gears, an extensive Finite Element Method (FEM) system was developed. The U.S. Army's XCH-62 HLH aft rotor transmission was finally successfully tested at full design torque and speed. A description of the test program is provided, and the analytical program is discussed. The analytical phase includes the development of a preprocessing program which aids in the review of calculated FEM stresses.

  18. Automatic transmission for a vehicle

    SciTech Connect

    Moroto, S.; Sakakibara, S.

    1986-12-09

    An automatic transmission is described for a vehicle, comprising: a coupling means having an input shaft and an output shaft; a belt type continuously-variable speed transmission system having an input pulley mounted coaxially on a first shaft, an output pulley mounted coaxially on a second shaft and a belt extending between the first and second pulleys to transfer power, each of the first and second pulleys having a fixed sheave and a movable sheave. The first shaft is disposed coaxially with and rotatably coupled with the output shaft of the coupling means, the second shaft being disposed side by side and in parallel with the first shaft; a planetary gear mechanism; a forward-reverse changeover mechanism and a low-high speed changeover mechanism.

  19. Transmission of influenza A viruses.

    PubMed

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-05-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to 'novel' viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages.

  20. Transmission of Influenza A Viruses

    PubMed Central

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to ‘novel’ viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

  1. Defect tolerant transmission lithography mask

    DOEpatents

    Vernon, Stephen P.

    2000-01-01

    A transmission lithography mask that utilizes a transparent substrate or a partially transparent membrane as the active region of the mask. A reflective single layer or multilayer coating is deposited on the membrane surface facing the illumination system. The coating is selectively patterned (removed) to form transmissive (bright) regions. Structural imperfections and defects in the coating have negligible effect on the aerial image of the mask master pattern since the coating is used to reflect radiation out of the entrance pupil of the imaging system. Similarly, structural imperfections in the clear regions of the membrane have little influence on the amplitude or phase of the transmitted electromagnetic fields. Since the mask "discards," rather than absorbs, unwanted radiation, it has reduced optical absorption and reduced thermal loading as compared to conventional designs. For EUV applications, the mask circumvents the phase defect problem, and is independent of the thermal load during exposure.

  2. Contraband detection using neutron transmission

    NASA Astrophysics Data System (ADS)

    Miller, Thomas G.; Van Staagen, P. K.; Gibson, Blake C.; Orthel, John L.; Krauss, Ronald A.

    1997-02-01

    A neutron transmission spectrometer, the multi-dimensional neutron radiometer (MDNR) has been used to determine the presence of contraband substances in sealed containers. A pulsed 'white' neutron source was created by allowing a pulsed beam of 5.5 MeV deuterons to impinge on a thick beryllium target. The neutron intensity was measured from about 0.75 MeV to about 4 MeV, first with the sample out of the beam and then with the sample in the beam, to determine the neutron attenuation. Both collimated beam and cone beam geometries were employed. The collimated beam experiments have been used to determine the presence of contraband with a high degree of accuracy. The present work describes a neural network computer simulation and real-time data reduction program for contraband detection using neutron transmission.

  3. Cultural transmission of social essentialism

    PubMed Central

    Rhodes, Marjorie; Leslie, Sarah-Jane; Tworek, Christina M.

    2012-01-01

    Social essentialism entails the belief that certain social categories (e.g., gender, race) mark fundamentally distinct kinds of people. Essentialist beliefs have pernicious consequences, supporting social stereotyping and contributing to prejudice. How does social essentialism develop? In the studies reported here, we tested the hypothesis that generic language facilitates the cultural transmission of social essentialism. Two studies found that hearing generic language about a novel social category diverse for race, ethnicity, age, and sex led 4-y-olds and adults to develop essentialist beliefs about that social category. A third study documented that experimentally inducing parents to hold essentialist beliefs about a novel social category led them to produce more generic language when discussing the category with their children. Thus, generic language facilitates the transmission of essentialist beliefs about social categories from parents to children. PMID:22869722

  4. Transmission optical coherence tomography sensing

    NASA Astrophysics Data System (ADS)

    Trull, A. K.; van der Horst, J.; Bijster, J. G.; Kalkman, J.

    2016-04-01

    We demonstrate that Fourier-domain transmission OCT is a versatile tool to measure optical material properties of turbid media. We develop an analytical expression for the transmission OCT signal. Based on this analysis we determine the group refractive index, group velocity dispersion, absorption coefficient, and scattering coefficient. The optical dispersion is accurately measured for glasses, liquids, and water/glucose mixtures. The optical attenuation is measured in the spatial domain and compared to Mie calculations combined with concentration dependent scattering effects. In the wave vector domain the spectral dependence of the optical attenuation is measured and compared to literature values. The developed technique can be used for optical sensing of attenuation and dispersion.

  5. Advanced Rotorcraft Transmission program summary

    NASA Astrophysics Data System (ADS)

    Bossler, Robert B., Jr.; Heath, Gregory F.

    1992-07-01

    The current status of the Advanced Rotorcraft Transmission (ART) program is reviewed. The discussion includes a general configuration and face gear description, weight analysis, stress analysis, reliability analysis, acoustic analysis, face gear testing, and planned torque split testing. Design descriptions include the face gear webs sized for equal stiffness, a positive engagement clutch, the lubrication system, and a high contact ratio planetary. Test results for five gear materials and three housing materials are presented.

  6. High efficiency ground data transmission

    NASA Technical Reports Server (NTRS)

    Dickinson, W. B.

    1973-01-01

    It is demonstrated that state-of-the-art communications technology can be implemented and reliably operated on a global basis to increase the transmission rates and efficiencies on circuits with bandwidths greater than the typical speech channel. Optimization is affected by optimum clock recovery procedures, multilevel pulse amplitude modulation, single sideband amplitude modulation, transversal filter equalizers, data scrambling, and active compensation for phase instability.

  7. Midwest Transmission Workshop II Summary

    SciTech Connect

    Kevin Bryan

    2002-12-05

    OAK-B135 After introductions of all participants, Abby Arnold, RESOLVE, reviewed the purpose of the meeting and the agenda. The purpose of the workshop was to share the results of the Midwest Independent System Operator (MISO) scenario development for wind and other fuel sources and the corresponding implications for transmission throughout the MISO control area. The workshop agenda is included in Attachment A.

  8. Investigation of polycapillary structures transmission

    NASA Astrophysics Data System (ADS)

    Chertov, Yuri P.

    2002-07-01

    For technological proces of polycapillary produciotn and for their further use it is necessary to know x-ray radiation transmission by polycapillary structures and its dependence on quanta energy. For this purpose special installation was assembled, technique was worked out and measurements were carried out. This paper incldues a description of the set-up, details the process of measurement and covers the outcome results.

  9. Immunology of naturally transmissible tumours.

    PubMed

    Siddle, Hannah V; Kaufman, Jim

    2015-01-01

    Naturally transmissible tumours can emerge when a tumour cell gains the ability to pass as an infectious allograft between individuals. The ability of these tumours to colonize a new host and to cross histocompatibility barriers contradicts our understanding of the vertebrate immune response to allografts. Two naturally occurring contagious cancers are currently active in the animal kingdom, canine transmissible venereal tumour (CTVT), which spreads among dogs, and devil facial tumour disease (DFTD), among Tasmanian devils. CTVT are generally not fatal as a tumour-specific host immune response controls or clears the tumours after transmission and a period of growth. In contrast, the growth of DFTD tumours is not controlled by the Tasmanian devil's immune system and the disease causes close to 100% mortality, severely impacting the devil population. To avoid the immune response of the host both DFTD and CTVT use a variety of immune escape strategies that have similarities to many single organism tumours, including MHC loss and the expression of immunosuppressive cytokines. However, both tumours appear to have a complex interaction with the immune system of their respective host, which has evolved over the relatively long life of these tumours. The Tasmanian devil is struggling to survive with the burden of this disease and it is only with an understanding of how DFTD passes between individuals that a vaccine might be developed. Further, an understanding of how these tumours achieve natural transmissibility should provide insights into general mechanisms of immune escape that emerge during tumour evolution. © 2014 The Authors. Immunology published by John Wiley & Sons Ltd.

  10. Transmission risk of human trichinellosis.

    PubMed

    Takumi, Katsuhisa; Teunis, Peter; Fonville, Manoj; Vallee, Isabelle; Boireau, Pascal; Nöckler, Karsten; van der Giessen, Joke

    2009-02-23

    Trichinella is a food-borne parasitic zoonoses and human cases are still reported in Europe mainly due to the consumption of pig meat originating from small backyard farms. Infections originating from industrialized pig farming have not been reported for decades in Europe, due to control measures to prevent the transmission of Trichinella from wildlife by indoor housing and good management practices. Therefore, risk-based monitoring programs might replace individual carcass control in industrialized pig farming as described in EU legislation SANCO 2075/2005. Transmission of Trichinella species between wildlife and the risk that may pose to humans via consumption of contaminated pork meat has not been studied quantitatively. One pathway by which human trichinellosis can occur is the rat-pig-human route. To evaluate the transmission risk though this pathway the dose responses of rat, pig, and human were studied. Experimental T. spiralis infection was performed in rats with doses of as few as 10 parasites and the data set was analysed using a newly developed dose response model that describes larvae per gram (LPG). Experimental T. spiralis infection in pig was analysed in a similar way. Furthermore nine published outbreaks of human trichinellosis were analysed to determine the dose response in humans. The risk of human trichinellosis via the rat-pig-human transmission was simulated by the Monte Carlo method. A pair of female and male parasites representing the lowest infection pressure from the environment, led to the probability of human trichinellosis by consumption of 100g of raw pork meat equal to 5% via the studied rat-pig-human pathway. In the absence of rodent control near the farm, a low infection pressure from wildlife presents a relatively high risk of human trichinellosis via consumption of uncooked pork meat.

  11. Light aircraft sound transmission study

    NASA Technical Reports Server (NTRS)

    Atwal, M.; David, J.; Heitman, K.; Crocker, M. J.

    1983-01-01

    The revived interest in the design of propeller driven aircraft is based on increasing fuel prices as well as on the need for bigger short haul and commuter aircraft. A major problem encountered with propeller driven aircraft is propeller and exhaust noise that is transmitted through the fuselage sidewall structure. Part of the work which was conducted during the period April 1 to August 31, 1983, on the studies of sound transmission through light aircraft walls is presented.

  12. Exoplanet transmission spectroscopy using KMOS

    NASA Astrophysics Data System (ADS)

    Parviainen, Hannu; Aigrain, Suzanne; Thatte, Niranjan; Barstow, Joanna K.; Evans, Thomas M.; Gibson, Neale

    2015-11-01

    KMOS (K-Band Multi Object Spectrograph) is a novel integral field spectrograph installed in the Very Large Telescope's (VLT's) ANTU unit. The instrument offers an ability to observe 24 2.8 arcsec × 2.8 arcsec subfields positionable within a 7.2 arcmin patrol field, each subfield producing a spectrum with a 14 × 14-pixel spatial resolution. The main science drivers for KMOS are the study of galaxies, star formation, and molecular clouds, but its ability to simultaneously measure spectra of multiple stars makes KMOS an interesting instrument for exoplanet atmosphere characterization via transmission spectroscopy. We set to test whether transmission spectroscopy is practical with KMOS, and what are the conditions required to achieve the photometric precision needed, based on observations of a partial transit of WASP-19b, and full transits of GJ 1214b and HD 209458b. Our analysis uses the simultaneously observed comparison stars to reduce the effects from instrumental and atmospheric sources, and Gaussian processes to model the residual systematics. We show that KMOS can, in theory, deliver the photometric precision required for transmission spectroscopy. However, this is shown to require (a) pre-imaging to ensure accurate centring and (b) a very stable night with optimal observing conditions (seeing ˜0.8 arcsec). Combining these two factors with the need to observe several transits, each with a sufficient out-of-transit baseline (and with the fact that similar or better precision can be reached with telescopes and instruments with smaller pressure), we conclude that transmission spectroscopy is not the optimal science case to take advantage of the abilities offered by KMOS and VLT.

  13. Monitoring Atmospheric Transmission with FLAME

    NASA Astrophysics Data System (ADS)

    Zimmer, Peter C.; McGraw, J. T.; Zirzow, D. C.; Koppa, M.; Buttler-Pena, K.

    2014-01-01

    Calibration of ground-based observations in the optical and near-infrared requires precise and accurate understanding of atmospheric transmission, at least as precise and accurate as that required for the spectral energy distributions of science targets. Traditionally this has used the Langley extrapolation method, observing targets and calibrators over a range of airmass and extrapolating to zero airmass by assuming a plane-parallel homogeneous atmosphere. The technique we present uses direct measurements of the atmosphere to derive the transmission along the line of sight to science targets at a few well-chosen wavelengths. The Facility Lidar Atmospheric Monitor of Extinction (FLAME) is a 0.5m diameter three Nd:YAG wavelength (355nm, 532nm & 1064nm) elastic backscatter lidar system. Laser pulses are transmitted into the atmosphere in the direction of the science target. Photons scattered back toward the receiver by molecules, aerosols and clouds are collected and time-gated so that the backscatter intensity is measured as a function of range to the scattering volume. The system is housed in a mobile calibration lab, which also contains auxiliary instrumentation to provide a NIST traceable calibration of the transmitted laser power and receiver efficiency. FLAME was designed to create a million photons per minute signal from the middle stratosphere, where the atmosphere is relatively calm and dominated by molecules of the well-mixed atmosphere (O2 & N2). Routine radiosonde measurements of the density at these altitudes constrain the scattering efficiency in this region and, combined with calibration of the transmitter and receiver, the only remaining unknown quantity is the two-way transmission to the stratosphere. These measurements can inform atmospheric transmission models to better understand the complex and ever-changing observatory radiative transfer environment. FLAME is currently under active development and we present some of our ongoing measurements.

  14. Performance Study of OFDM Transmissions

    NASA Astrophysics Data System (ADS)

    Ledesma Goyzueta, Rodolfo

    2010-10-01

    The purpose of this study is to explore the important features of OFDM under different channel conditions and to analyze the outcomes. In order to procure this goal, multiple simulations are performed using GNU Octave. The simulations of OFDM transmissions are carried out under Additive White Gaussian Noise (AWGN) and/or Rayleigh fading. Besides, PACE is employed to mitigate the effects of Rayleigh fading.

  15. Advanced Rotorcraft Transmission program summary

    NASA Technical Reports Server (NTRS)

    Bossler, Robert B., Jr.; Heath, Gregory F.

    1992-01-01

    The current status of the Advanced Rotorcraft Transmission (ART) program is reviewed. The discussion includes a general configuration and face gear description, weight analysis, stress analysis, reliability analysis, acoustic analysis, face gear testing, and planned torque split testing. Design descriptions include the face gear webs sized for equal stiffness, a positive engagement clutch, the lubrication system, and a high contact ratio planetary. Test results for five gear materials and three housing materials are presented.

  16. High current pulse transmission cable

    SciTech Connect

    Parsons, W.M.

    1990-09-28

    This invention is comprised of a transmission cable for carrying high current pulses in which an even numbered plurality of electrical conductors surrounds a central ground conductor. Each electrical conductor is connected so that it at any instant in time it will carry current of opposite polarity to the polarity carried by adjacent conductors. This arrangement cancels practically all of the external fields generated by current in the conductors.

  17. Coiled transmission line pulse generators

    DOEpatents

    McDonald, Kenneth Fox

    2010-11-09

    Methods and apparatus are provided for fabricating and constructing solid dielectric "Coiled Transmission Line" pulse generators in radial or axial coiled geometries. The pour and cure fabrication process enables a wide variety of geometries and form factors. The volume between the conductors is filled with liquid blends of monomers, polymers, oligomers, and/or cross-linkers and dielectric powders; and then cured to form high field strength and high dielectric constant solid dielectric transmission lines that intrinsically produce ideal rectangular high voltage pulses when charged and switched into matched impedance loads. Voltage levels may be increased by Marx and/or Blumlein principles incorporating spark gap or, preferentially, solid state switches (such as optically triggered thyristors) which produce reliable, high repetition rate operation. Moreover, these Marxed pulse generators can be DC charged and do not require additional pulse forming circuitry, pulse forming lines, transformers, or an a high voltage spark gap output switch. The apparatus accommodates a wide range of voltages, impedances, pulse durations, pulse repetition rates, and duty cycles. The resulting mobile or flight platform friendly cylindrical geometric configuration is much more compact, light-weight, and robust than conventional linear geometries, or pulse generators constructed from conventional components. Installing additional circuitry may accommodate optional pulse shape improvements. The Coiled Transmission Lines can also be connected in parallel to decrease the impedance, or in series to increase the pulse length.

  18. Flavivirus transmission focusing on Zika.

    PubMed

    Vasilakis, Nikos; Weaver, Scott C

    2017-02-01

    Flaviviruses are among the most diverse viruses with over 85 species recognized. Taxonomically, this genus is one of the 4 recognized genera within the family Flaviviridae. Most flaviviruses of human public health significance, for example, dengue, yellow fever and Zika viruses, are arthropod-borne (arboviruses) and have two evolutionarily and ecologically distinct transmission cycles: a sylvatic transmission cycle, where the virus circulates between zoonotic vertebrate reservoir and amplification hosts and arboreal mosquitoes; and an urban transmission cycle, where the virus circulates between humans and peridomestic Aedes spp. mosquitoes. Zika virus (ZIKV), a flavivirus closely related to West Nile, dengue, Spondweni, Japanese encephalitis and yellow fever viruses, remained in obscurity since its discovery in 1947, but has recently emerged to cause a series of epidemics in the South Pacific, and most recently reaching nearly pandemic levels with its introduction in the Americas. Available epidemiologic and experimental evidence points to Aedes aegypti as the principal urban vector, possibly supplemented by Aedes albopictus in some locations. Unfortunately, the former is one of the most difficult mosquitoes to control owing to its highly anthropophilic behavior.

  19. Split torque transmission load sharing

    NASA Technical Reports Server (NTRS)

    Krantz, T. L.; Rashidi, M.; Kish, J. G.

    1992-01-01

    Split torque transmissions are attractive alternatives to conventional planetary designs for helicopter transmissions. The split torque designs can offer lighter weight and fewer parts but have not been used extensively for lack of experience, especially with obtaining proper load sharing. Two split torque designs that use different load sharing methods have been studied. Precise indexing and alignment of the geartrain to produce acceptable load sharing has been demonstrated. An elastomeric torque splitter that has large torsional compliance and damping produces even better load sharing while reducing dynamic transmission error and noise. However, the elastomeric torque splitter as now configured is not capable over the full range of operating conditions of a fielded system. A thrust balancing load sharing device was evaluated. Friction forces that oppose the motion of the balance mechanism are significant. A static analysis suggests increasing the helix angle of the input pinion of the thrust balancing design. Also, dynamic analysis of this design predicts good load sharing and significant torsional response to accumulative pitch errors of the gears.

  20. Heat transfer from oriented heat exchange areas

    NASA Astrophysics Data System (ADS)

    Vantuch, Martin; Huzvar, Jozef; Kapjor, Andrej

    2014-03-01

    This paper deals with the transfer of heat-driven heat transfer surface area in relation to the construction of the criterion equation for "n" horizontal pipe one about another. On the bases of theoretical models have been developed for calculating the thermal performance of natural convection by Churilla and Morgan, for various pipe diameters and temperatures. These models were compared with models created in CFD-Fluent Ansys the same boundary conditions. The aim of the analyse of heat and fluxional pipe fields "n" pipes one about another at natural convection is the creation of criterion equation on the basis of which the heat output of heat transfer from pipe oriented areas one above another with given spacing could be quantified. At presence a sum of criterion equations exists for simple geometrical shapes of individual oriented geometrical areas but the criterion equation which would consider interaction of fluxional field generated by free convection from multiple oriented areas is not mentioned in standardly accessible technical literature and other magazine publications.