Nugent, Paul W.; Shaw, Joseph A.; Pust, Nathan J.
2014-12-01
Advances in microbolometer long-wave infrared (LWIR) detectors have led to the common use of infrared cameras that operate without active temperature stabilization, but the response of these cameras varies with their own temperature. Therefore, obtaining quantitative data requires a calibration that compensates for these errors. This paper describes a method for stabilizing the camera's response through software processing of consecutive images of the scene and images of the camera's internal shutter. An image of the shutter is processed so that it appears as if it were viewed through the lens. The differences between the scene and the image of the shutter treated as an external blackbody are then related to the radiance or temperature of the objects in the scene. This method has been applied to two commercial LWIR cameras over a focal plane array temperature range of ±7.2°C, changing at a rate of up to ±0.5°C/min. During these tests, the rms variability of the camera output was reduced from ±4.0°C to ±0.26°C.
Liu, Changxu
2015-01-01
We investigate both theoretically and experimentally a new type of laser, which exploits a broadband light "condensation" process sustained by the stimulated amplification of an optical blackbody metamaterial. © 2014 Optical Society of America.
Stream Gauges and Satellite Measurements
Alsdorf, D. E.
2010-12-01
Satellite measurements should not be viewed as a replacement for stream gauges. However, occasionally it is suggested that because satellite-based measurements can provide river discharge, a motivation for satellite approaches is an increasing lack of stream gauges. This is an argument for more stream gauges, but not necessarily for satellite measurements. Rather, in-situ and spaceborne methods of estimating discharge are complementary. Stream gauges provide frequent measurements at one point in the river reach whereas satellites have the potential to measure throughout all reaches but at orbital repeat intervals of days to weeks. The Surface Water and Ocean Topography satellite mission (SWOT) is an opportunity to further develop these complements. The motivation for SWOT, and indeed for any satellite based method of estimating discharge, should not be as a replacement for stream gauges. Scientific and application uses should motivate the measurements. For example, understanding floods with their dynamic water surfaces are best sampled from remote platforms that provide water surface elevations throughout the floodwave. As another example, today’s water and energy balance models are giving outputs at increasing spatial resolution and are making use of water surface elevations throughout the modeled basin. These models require a similar resolution in the calibrating and validating observations. We should also be aware of practical limitations. In addition to providing spatially distributed hydrodynamic measurements on rivers, SWOT will be able to measure storage changes in the estimated 30 million lakes in the world that are larger than a hectare. Knowing the storage changes in these lakes is especially important in certain regions such as the Arctic but gauging even a small fraction of these is impractical. Another motivator for satellite methods is that even in the presence of stream gauges, discharge data is not always well shared throughout all countries
Spectral emissivity of surface blackbody calibrators
DEFF Research Database (Denmark)
Clausen, Sønnik
2007-01-01
The normal spectral emissivity of commercial infrared calibrators is compared with measurements of anodized aluminum samples and grooved aluminum surfaces coated with Pyromark. Measurements performed by FTIR spectroscopy in the wavelength interval from 2 to 20 mu m and at temperatures between 5...... in emissivity using similar materials can be reduced to 0.5-1% by optimizing the coating process and the surface geometry. Results are discussed and an equation for calculation of the equivalent blackbody surface temperature from FTIR spectra is presented, including reflected ambient radiation. It is in most...... cases necessary to correct temperature calibration results for calibrators calibrated at 8-14 mu m to obtain absolute accuracies of 0.1-1 degrees C in other spectral regions depending on the temperature. Uncertainties are discussed and equations are given for the correction of measured radiation...
Blackbody Radiation from Isolated Neptunes
Ginzburg, Sivan; Loeb, Abraham
2016-01-01
Recent analyses of the orbits of some Kuiper Belt objects hypothesize the presence of an undiscovered Neptune-size planet at a very large separation from the Sun. The energy budget of Neptunes on such distant orbits is dominated by the internal heat released by their cooling rather than solar irradiation (making them effectively "isolated"). The blackbody radiation that these planets emit as they cool may provide the means for their detection. Here we use an analytical toy model to study the cooling and radiation of isolated Neptunes. This model can translate a detection (or a null detection) to a constraint on the size and composition of the hypothesized "Planet Nine". Specifically, the thick gas atmosphere of Neptune-like planets serves as an insulating blanket which slows down their cooling. Therefore, a measurement of the blackbody temperature, $T_{\\rm eff}\\sim 50\\textrm{K}$, at which a Neptune emits can be used to estimate the mass of its atmosphere, $M_{\\rm atm}$. Explicitly, we find the relation $T_{\\r...
Blackbody Radiation from Isolated Neptunes
Ginzburg, Sivan; Sari, Re'em; Loeb, Abraham
2016-05-01
Recent analyses of the orbits of some Kuiper belt objects hypothesize the presence of an undiscovered Neptune-size planet at a very large separation from the Sun. The energy budget of Neptunes on such distant orbits is dominated by the internal heat released by their cooling rather than solar irradiation (making them effectively “isolated”). The blackbody radiation that these planets emit as they cool may provide the means for their detection. Here, we use an analytical toy model to study the cooling and radiation of isolated Neptunes. This model can translate a detection (or a null detection) to a constraint on the size and composition of the hypothesized “Planet Nine.” Specifically, the thick gas atmosphere of Neptune-like planets serves as an insulating blanket that slows down their cooling. Therefore, a measurement of the blackbody temperature, {T}{{eff}}˜ 50 {{K}}, at which a Neptune emits, can be used to estimate the mass of its atmosphere, {M}{{atm}}. Explicitly, we find the relation {T}{{eff}}\\propto {M}{{atm}}1/12. Despite this weak relation, a measurement of the flux at the Wien tail can constrain the atmospheric mass, at least to within a factor of a few, and provide useful limits to possible formation scenarios of these planets. Finally, we constrain the size and composition of Planet Nine by combining our model with the null results of recent all-sky surveys.
A pathway to generating Climate Data Records of sea-surface temperature from satellite measurements
Minnett, Peter J.; Corlett, Gary K.
2012-11-01
In addition to having known uncertainty characteristics, Climate Data Records (CDRs) of geophysical variables derived from satellite measurements must be of sufficient length to resolve signals that might reveal the signatures of climate change against a background of larger, unrelated variability. The length of the record requires using satellite measurements from many instruments over several decades, and the uncertainty requirement implies that a consistent approach be used to establish the errors in the satellite retrievals over the entire period. Retrieving sea-surface temperature (SST) from satellite is a relatively mature topic, and the uncertainties of satellite retrievals are determined by comparison with collocated independent measurements. To avoid the complicating effects of near-surface temperature gradients in the upper ocean, the best validating measurements are from ship-board radiometers that measure, at source, the surface emission that is measured in space, after modification by its propagation through the atmosphere. To attain sufficient accuracy, such ship-based radiometers must use internal blackbody calibration targets, but to determine the uncertainties in these radiometric measurements, i.e. to confirm that the internal calibration is effective, it is necessary to conduct verification of the field calibration using independent blackbodies with accurately known emissivity and at very accurately measured temperatures. This is a well-justifiable approach to providing the necessary underpinning of a Climate Data Record of SST.
Smerlak, Matteo
2010-01-01
We discuss carefully the blackbody approximation, stressing what it is (a limit case of radiative transfer), and what it is not (the assumption that the body is perfectly absorbing, i.e. black). Furthermore, we derive the Planck spectrum without enclosing the field in a box, as is done in most textbooks. Athough convenient, this trick conceals the nature of the idealization expressed in the concept of a blackbody: first, the most obvious examples of approximate blackbodies, stars, are definitely not enclosed in boxes; second, the Planck spectrum is continuous, while the stationary modes of radiation in a box are discrete. Our derivation, although technically less elementary, is conceptually more consistent, and brings the opportunity to introduce to students the important concept of local density of states, via the resolvent formalism.
Smerlak, Matteo
2011-09-01
We discuss carefully the blackbody approximation, stressing what it is (a limit case of radiative transfer), and what it is not (the assumption that the body is perfectly absorbing, namely black). Furthermore, we derive the Planck spectrum without enclosing the field in a box, as is done in most textbooks. Although convenient, this trick conceals the nature of the idealization expressed in the concept of a blackbody: first, the most obvious examples of approximate blackbodies, stars, are definitely not enclosed in boxes; second, the Planck spectrum is continuous, while the stationary modes of radiation in a box are discrete. Our derivation, although technically less elementary, is conceptually more consistent, and brings the opportunity to introduce to advanced undergraduate and graduate students the important concept of the local density of states via the resolvent formalism.
Blackbody Radiation in Optically Thick Gases?
Directory of Open Access Journals (Sweden)
Robitaille P.-M.
2014-07-01
Full Text Available In this work, the claim that optically thick gases can emit as blackbodies is refuted. The belief that such behavior exists results from an improper consideration of heat transfer and reflection. When heat is injected into a gas, the energy is primarily redistributed into translational degrees of freedom and is not used to drive emission. The average kinetic energy of the particles in the system simply increases and the temperature rises. In this respect, it is well-know that the emissivity of a gas can drop with increasing temperature. Once reflection and translation are properly considered, it is simple to understand why gases can never emit as blackbodies.
Blackbody Radiation from an Incandescent Lamp
Ribeiro, C. I.
2014-01-01
In this article we propose an activity aimed at introductory students to help them understand the Stefan-Boltzmann and Wien's displacement laws. It only requires simple materials that are available at any school: an incandescent lamp, a variable dc energy supply, and a computer to run an interactive simulation of the blackbody spectrum.…
Atomic clocks with suppressed blackbody radiation shift
Yudin, V I; Okhapkin, M V; Bagayev, S N; Tamm, Chr; Peik, E; Huntemann, N; Mehlstaubler, T E; Riehle, F
2011-01-01
We develop a nonstandard concept of atomic clocks where the blackbody radiation shift (BBRS) and its temperature fluctuations can be dramatically suppressed (by one to three orders of magnitude) independent of the environmental temperature. The suppression is based on the fact that in a system with two accessible clock transitions (with frequencies $\
Satellite measurements of formaldehyde from shipping emissions
Directory of Open Access Journals (Sweden)
T. Marbach
2009-04-01
Full Text Available International shipping is recognized as a pollution source of growing importance, in particular in the remote marine boundary layer. Nitrogen dioxide originating from ship emissions has previously been detected in satellite measurements. This study presents the first satellite measurements of formaldehyde (HCHO linked to shipping emissions as derived from observations made by the Global Ozone Monitoring Experiment (GOME instrument.
We analyzed enhanced HCHO tropospheric columns from shipping emissions over the Indian Ocean between Sri Lanka and Sumatra. This region offers good conditions in term of plume detection with the GOME instrument as all ship tracks follow a single narrow track in the same east-west direction as used for the GOME pixel scanning. The HCHO signal alone is weak but could be clearly seen in the high-pass filtered data. The line of enhanced HCHO in the Indian Ocean as seen in the 7-year composite of cloud free GOME observations clearly coincides with the distinct ship track corridor from Sri Lanka to Indonesia. The observed mean HCHO column enhancement over this shipping route is about 2.0×10^{15} molec/cm^{2}.
The observed HCHO pattern also agrees qualitatively well with results from the coupled earth system model ECHAM5/MESSy applied to atmospheric chemistry (EMAC. However, the modelled HCHO values over the ship corridor are two times lower than in the GOME high-pass filtered data. This might indicate that the used emission inventories are too low and/or that the in-plume chemistry taking place in the narrow path of the shipping lanes are not well represented at the rather coarse model resolution.
Blackbody for metrological control of ear thermometers
Cárdenas-García, D.; Méndez-Lango, E.
2013-09-01
Body temperature is an important parameter in medical practice, and most of health diagnoses are made based upon measured temperature values. Non-contact measurements are attractive to both patients and physicians, and ear thermometers (ET) are part of the set of infrared thermometers for medical applications. ETs sense the tympanic membrane temperature which best represents body temperature. They take advantage of the natural high effective emissivity cavity that is formed as radiation source. To calibrate or to check the performance of ETs, we designed a high-emissivity spherical cavity as a blackbody source which can be placed in a dry block oven. Although the blackbody cavity can have any shape, we decided to build it spherical because its effective emissivity can be easily calculated in a closed form. The cavity is made of Aluminum to take advantage of its high thermal conductivity while its inner side is covered with a black paint to increase the cavity effective emissivity. Based on paint emissivity measurements and the geometrical shape, we calculated that the cavity has an effective emissivity higher than 0.999. Blackbody temperature is measured with a calibrated contact thermometer placed inside the bottom wall of the cavity. We present the design of the cavity, the experimental setup, and results of three commercial ETs compared with this cavity.
mbb_emcee: Modified Blackbody MCMC
Conley, Alexander
2016-02-01
Mbb_emcee fits modified blackbodies to photometry data using an affine invariant MCMC. It has large number of options which, for example, allow computation of the IR luminosity or dustmass as part of the fit. Carrying out a fit produces a HDF5 output file containing the results, which can either be read directly, or read back into a mbb_results object for analysis. Upper and lower limits can be imposed as well as Gaussian priors on the model parameters. These additions are useful for analyzing poorly constrained data. In addition to standard Python packages scipy, numpy, and cython, mbb_emcee requires emcee (ascl:1303.002), Astropy (ascl:1304.002), h5py, and for unit tests, nose.
Numerical Models of Blackbody-Dominated GRBs
Cuesta-Martínez, Carlos F; Mimica, Petar; Thöne, Christina C; de Ugarte-Postigo, Antonio
2015-01-01
Blackbody-dominated (BBD) gamma-ray bursts (GRBs) are events characterized by the absence of a typical afterglow, long durations and the presence of a significant thermal component following the prompt gamma-ray emission. GRB 101225A (the `Christmas burst') is a prototype of this class. A plausible progenitor system for it, and for the BBD-GRBs, is the merger of a neutron star (NS) and a helium core of an evolved, massive star. Using relativistic hydrodynamic simulations we model the propagation of an ultrarelativistic jet through the enviroment created by such a merger and we compute the whole radiative signature, both thermal and non-thermal, of the jet dynamical evolution. We find that the thermal emission originates from the interaction between the jet and the hydrogen envelope ejected during the NS/He merger.
Comparison of Blackbodies for Calibration of Infrared Ear Thermometers
DEFF Research Database (Denmark)
Pušnik, Igor; Clausen, Sønnik; Favreau, Jacques-Olivier
2011-01-01
. To verify the accuracy of an IRET, a suitable blackbody (BB) is needed. Such a blackbody related to the EN standard, designed for the calibration of ear thermometers and immersed in a stirred water bath, was provided for the comparison by the pilot laboratory. The pilot provided also the transfer IRET...
Integration Of GPS And GLONASS Systems In Geodetic Satellite Measurements
Maciuk, Kamil
2015-12-01
The article shows the results of satellites measurements elaborations using GPS & GLONASS signals. The aim of this article is to define the influence of adding GLONASS signals on position determination accuracy. It especially concerns areas with big horizon coverages. Object of the study were analysis of DOP coefficients, code and RTK solutions, and usage of satellite techniques in levelling. The performed studies and analysis show that integrated GPS-GLONASS satellite measurements provide possibility to achieve better results than measurements using single navigation satellite system (GPS).
Determination of atmospheric aerosol properties over land using satellite measurements
Kokhanovsky, A.A.; Leeuw, G. de
2009-01-01
Mostly, aerosol properties are poorly understood because the aerosol properties are very sparse. The first workshop on the determination of atmospheric aerosol properties over land using satellite measurements is convened in Bremen, Germany. In this workshop, the topics of discussions included a var
Comparison of blackbodies for calibration of infrared ear thermometers
DEFF Research Database (Denmark)
Pusnik, Igor; Clausen, Sønnik; Favreau, Jacques-Olivier
2010-01-01
The article will present the results of the EURAMET project no. 927 "Comparison of blackbodies for calibration of infrared ear thermometers (IRETs)". For the comparison MIRS/UL-FE LMK was chosen as the pilot laboratory. The objective of the comparison was to determine the agreement of blackbodies...... this is the standard EN 12470-5, which is a harmonised standard and supports the Medical Device Directive (MDD). Other standards are ASTM standard, Designation E 1965 – 98 and the draft of Japan Industrial Standard JIS T 4207, 2005: Japanese Industrial Standard: “infrared ear thermometers.”. The International...... is required to be at the most ±0,07 °C. An example of a blackbody is presented in Annex C of the standard EN 12470-5. Such a blackbody related to this standard, designed for the calibration of ear thermometers and immersed in a stirred water bath, was provided for the comparison by the pilot laboratory...
MODIS On-board Blackbody Performance
Xiong, Xiaoxiong; Chen, N.; Wu, A.; Wenny, B.; Dodd, J.
2008-01-01
Currently, there are two MODIS instruments operated on-orbit: one on-board the Terra spacecraft launched in December 1999 and the other on-board the Aqua spacecraft launched in May 2002. MODIS is a scanning radiometer that has 16 thermal emissive bands (TEBs) in the MWIR and LWIR regions. The remaining spectral bands are in the VISINIR and SWIR regions. The TEBs have a total of 160 detectors (10 detectors per band), which are calibrated on-orbit using an on-board blackbody (BB). MODIS TEB calibration is performed via a quadratic algorithm with its linear calibration coefficients updated on a scan-by-scan basis using each detector's response to the BB. The offset and nonlinear terms of the quadratic calibration equation are stored in a look-up table (LUT). The LUT parameters are derived from pre-launch calibration and updated on-orbit from BB observations, as needed. Typically, the BB is set at a fixed temperature. Periodically, a warm-up and cool-down activity is performed, which enables the BB temperature to be varied from instrument ambient up to 315K. The temperature of the BB is measured each scan using 12 thermistors, which were fully characterized pre-launch with reference to the NIST temperature scale. This paper describes MODIS on-board BB operational activities and performance. The TEB detector response (short-term stability and long-term changes) and noise characterization results derived from BB observations and their impact on the TEB calibration uncertainty are also presented.
Effective temperature and exergy of monochromic blackbody radiation
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
A new parameter named monochromic effective temperature Tλ is proposed, which represents the thermodynamic quality of monochromic blackbody radiation. The exergy of the monochromic blackbody radiation is expressed by Tλ. The monochromic effective temperature equation is developed, which shows that the produci of Tλ and the wavelength is constant, which equals 5.33016×10-3 tion in photosynthesis can be explained by the results of this work.
The Next Generation Heated Halo for Blackbody Emissivity Measurement
Gero, P.; Taylor, J. K.; Best, F. A.; Revercomb, H. E.; Knuteson, R. O.; Tobin, D. C.; Adler, D. P.; Ciganovich, N. N.; Dutcher, S. T.; Garcia, R. K.
2011-12-01
The accuracy of radiance measurements from space-based infrared spectrometers is contingent on the quality of the calibration subsystem, as well as knowledge of its uncertainty. Future climate benchmarking missions call for measurement uncertainties better than 0.1 K (k=3) in radiance temperature for the detection of spectral climate signatures. Blackbody cavities impart the most accurate calibration for spaceborne infrared sensors, provided that their temperature and emissivity is traceably determined on-orbit. The On-Orbit Absolute Radiance Standard (OARS) has been developed at the University of Wisconsin to meet the stringent requirements of the next generation of infrared remote sensing instruments. It provides on-orbit determination of both traceable temperature and emissivity for calibration blackbodies. The Heated Halo is the component of the OARS that provides a robust and compact method to measure the spectral emissivity of a blackbody in situ. A carefully baffled thermal source is placed in front of a blackbody in an infrared spectrometer system, and the combined radiance of the blackbody and Heated Halo reflection is observed. Knowledge of key temperatures and the viewing geometry allow the blackbody cavity spectral emissivity to be calculated. We present the results from the Heated Halo methodology implemented with a new Absolute Radiance Interferometer (ARI), which is a prototype space-based infrared spectrometer designed for climate benchmarking that was developed under the NASA Instrument Incubator Program (IIP). We compare our findings to models and other experimental methods of emissivity determination.
Low-temperature blackbodies and facility for calibration of them
Morozova, Svetlana P.; Morozov, Pavel A.; Sapritsky, Victor I.; Lisiansky, Boris E.; Dovgilov, N. L.; Liang, Yanxi; Li, Yanmei; Yue, Wenlong
2002-09-01
The calibration of IR sensors, thermal imagers, instrumentation for remote earth sensing, signature recognition, and low background spacebome radiom-eters requires development of low- and near-ambient-temperature reference standard sources capable of operating in vacuum at low or medium background conditions. The paper contains the characteristics of blackbodies (BB), developed at the All-Russian Research Institute for Optical and Physical Measurements (VNIIOFI). A novel Medium Background Facility (MBF) intended for calibrating IR sources has been developed at VNIIOFI. The MBF used for the calibration under vacuum conditions (10-3 Pa) and medium background temperatures includes a Ga Fixed-Point Blackbody (29.76 °C), Variable Temperature Blackbody (-60 °C ~ +80 °C) and Filter Radiometer. A brief description of the operating principles and specifications of the MBF is presented. The results of a comparison of the Variable Temperature Blackbody and Ga Fixed Point Blackbody in the Medium Background Facility are given. The measurement uncertainties radiance temperature associated with spectral bandwidth are discussed.
Can a quantum critical state represent a blackbody?
Chakravarty, Sudip
2016-01-01
The blackbody theory of Planck played a seminal role in the development of quantum theory at the turn of the past century. A blackbody cavity is generally thought to be a collection of photons in thermal equilibrium; the radiation emitted is at all wavelengths, and the intensity follows a scaling law, which is Planck's characteristic distribution law. These photons arise from non-interacting normal modes. Here we suggest that certain quantum critical states when heated emit "radiation" at all wavelengths and satisfy all the criteria of a blackbody. An important difference is that the "radiation" does not necessarily consist of non-interacting photons, but also emergent relativistic bosons or fermions. The examples we provide include emergent relativistic fermions at a topological quantum critical point. This perspective on a quantum critical state may be illuminating in many unforeseen ways.
Thermodynamic properties of the blackbody radiation: A Kaniadakis approach
Lourek, Imene; Tribeche, Mouloud
2017-02-01
The thermodynamic properties of the blackbody radiation are revisited, for the first time, within the theoretical framework of the κ-statistics introduced by Kaniadakis. Using the κ-counterpart of the Bose-Einstein distribution, generalized expressions for the free energy, the entropy, the specific heat, and the pressure are obtained. All quantities are shown to recover their standard expressions in the limit κ → 0. The reexamination of the thermodynamic properties of the blackbody radiation shows that it emits more energy with an increase of the value of | κ | in comparison with the standard Planck radiation law. Moreover, the effects of the deformed Kaniadakis statistics are shown to be more appreciable for high temperatures. Our results could be used as a theoretical support for experimental studies implying blackbody radiation such as the study of microwave background radiation.
The Heated Halo for Space-Based Blackbody Emissivity Measurement
Gero, P.; Taylor, J. K.; Best, F. A.; Revercomb, H. E.; Garcia, R. K.; Adler, D. P.; Ciganovich, N. N.; Knuteson, R. O.; Tobin, D. C.
2012-12-01
The accuracy of radiance measurements with space-based infrared spectrometers is contingent on the quality of the calibration subsystem, as well as knowledge of its uncertainty. Upcoming climate benchmark missions call for measurement uncertainties better than 0.1 K (k=3) in radiance temperature for the detection of spectral climate signatures. Blackbody cavities impart the most accurate calibration for spaceborne infrared sensors, provided that their temperature and emissivity is traceably determined on-orbit. The On-Orbit Absolute Radiance Standard (OARS) has been developed at the University of Wisconsin and has undergone further refinement under the NASA Instrument Incubator Program (IIP) to meet the stringent requirements of the next generation of infrared remote sensing instruments. It provides on-orbit determination of both traceable temperature and emissivity for calibration blackbodies. The Heated Halo is the component of the OARS that provides a robust and compact method to measure the spectral emissivity of a blackbody in situ. A carefully baffled thermal source is placed in front of a blackbody in an infrared spectrometer system, and the combined radiance of the blackbody and Heated Halo reflection is observed. Knowledge of key temperatures and the viewing geometry allow the blackbody cavity spectral emissivity to be calculated. We present the results from the Heated Halo methodology implemented with a new Absolute Radiance Interferometer (ARI), which is a prototype space-based infrared spectrometer designed for climate benchmarking. We show the evolution of the technical readiness level of this technology and we compare our findings to models and other experimental methods of emissivity determination.
Thermodynamics of Phase Transitions of a Kerr Nonlinear Blackbody
Institute of Scientific and Technical Information of China (English)
CHENG Ze
2008-01-01
We study the thermodynamics of phase transitions of a blackbody whose interior is filled by a Kerr nonlinear crystal. There is a transition temperature To, above which the Kerr nonlinear blackbody is in the normal thermal radiation state, and below which it is in the squeezed thermal radiation state. At To, the Gibbs free energy of the two phases is continuous but the entropy density of the two phases is discontinuous. Hence, there is a jump in the entropy density and this leads to a latent heat density. The photon system undergoes a first-order phase transition from the normal to the squeezed thermal radiation state.
A regularized GMRES method for inverse blackbody radiation problem
Directory of Open Access Journals (Sweden)
Wu Jieer
2013-01-01
Full Text Available The inverse blackbody radiation problem is focused on determining temperature distribution of a blackbody from measured total radiated power spectrum. This problem consists of solving a first kind of Fredholm integral equation and many numerical methods have been proposed. In this paper, a regularized GMRES method is presented to solve the linear ill-posed problem caused by the discretization of such an integral equation. This method projects the orignal problem onto a lower dimensional subspaces by the Arnoldi process. Tikhonov regularization combined with GCV criterion is applied to stabilize the numerical iteration process. Three numerical examples indicate the effectiveness of the regularized GMRES method.
NOx emission trends in megacities derived from satellite measurements
Konovalov, Igor; Beekmann, Matthias; Richter, Andreas
2010-05-01
The effects of air pollutant emissions on both local air quality in megacities and composition of the atmosphere on regional and global scales are currently an important issue of atmospheric researches. In order to properly evaluate these effects, atmospheric models should be provided with accurate information on emissions of major air pollutants. However, such information is frequently very uncertain, as it is documented in literature. The quantification of emissions and related effects is an especially difficult task in the case of developing countries. Recently, it has been demonstrated that satellite measurements of nitrogen dioxide (NO2) can be used as a source of independent information on NOx emissions. In particular, the satellite measurements were used in our earlier studies to improve spatial allocation of NOx emissions, to estimate multi-annual changes of NOx emissions on regional scales and to validate data of traditional emission inventories (see Ref. 1, 2). The goals of the present study are (1) developing an efficient method for estimation of NOx emissions trend in megacity regions by using satellite measurements and an inverse modeling technique and (2) obtaining independent estimates of NOx emission trends in several megacities in Europe and the Middle East in the period from 1996 to 2008. The study is based on the synergetic use of the data for tropospheric NO2 column amounts derived from the long-term GOME and SCIAMACHY measurements and simulations performed by the CHIMERE chemistry transport model. We performed the analysis involving methods of different complexity ranging from estimation of linear trends in the tropospheric NO2 columns retrieved from satellite measurements to evaluation of nonlinear trends in NOx emission estimates obtained with the inverse modeling approach, which, in the given case, involves only very simple and transparent formulations. The most challenging part of the study is the nonlinear trend estimation, which is
Evaluation of Aerosol Properties in GCMs using Satellite Measurements
Wang, Y.; Jiang, J. H.; Su, H.; Zhang, H.
2015-12-01
Atmospheric aerosols from natural or anthropogenic sources have profound impacts on the regional and global climate. Currently the radiative forcing of aerosols predicted by global climate models remains highly uncertain, representing the largest uncertainty in climate predictions. The uncertainty mainly arises from the complicated aerosol chemical and physical properties, coarse emission inventories for pre-cursor gases as well as unrealistic representations of aerosol activation and cloud processing in global climate models. In this study, we will utilize multiple satellite measurements including MODIS, MISR and CALIPSO to quantitatively evaluate aerosol simulations from climate models. Our analyses show that the global means in AOD climatology from NCAR CAM5 and GFDL AM3 simulations are comparable with satellite measurements. However, the overall correlation coefficient between the AOD spatial patterns from CAM5 and satellite is only 0.4. Moreover, at finer scales, the magnitude of AOD in CAM5 is much lower than satellite measurements for most of the non-dust regions, especially over East Asia. GFDL AM3 shows better AOD simulations over East Asia. The underestimated AOD over remote maritime areas in CAM5 was attributed to the unrealistic wet removal processes in convective clouds of CAM5. Over continents, biases on AOD could stem from underestimations in the emissions inventory and unresolved sub-grid variations of relative humidity due to the model's coarse resolution. Uncertainty from emission inventory over developing countries in East Asia will be assessed using the newly updated Regional Emission inventory in Asia (REAS) and Multi-resolution Emission Inventory in China (MEIC) in the model simulations.
Satellite measurements of the earth's crustal magnetic field
Schnetzler, C. C.
1989-01-01
The literature associated with the Magsat mission has evaluated the capabilities and limitations of satellite measurements of the earth's crustal magnetic field, and demonstrated that there exists a 300-3000 km magnetic field, related to major features in the earth's crust, which is primarily caused by induction. Due to its scale and sensitivity, satellite data have been useful in the development of models for such large crustal features as subduction zones, submarine platforms, continental accretion boundaries, and rifts. Attention is presently given to the lack of agreement between laboratory and satellite estimates of lower crustal magnetization.
Blackbody radiation shift in 87Rb frequency standard
Safronova, M S; Safronova, U I
2010-01-01
The operation of atomic clocks is generally carried out at room temperature, whereas the definition of the second refers to the clock transition in an atom at absolute zero. This implies that the clock transition frequency should be corrected in practice for the effect of finite temperature of which the leading contributor is the blackbody radiation (BBR) shift. Experimental measurements of the BBR shifts are difficult. In this work, we have calculated the blackbody radiation shift of the ground-state hyperfine microwave transition in 87Rb using the relativistic all-order method and carried out detailed evaluation of the accuracy of our final value. Particular care is taken to accurately account for the contributions from highly-excited states. Our predicted value for the Stark coefficient, k_S=-1.240(4)\\times 10^{-10}\\text{Hz/(V/m)}^{2} is three times more accurate than the previous calculation [1].
Blackbody radiation shift in ^87Rb frequency standard
Safronova, Marianna; Safronova, U. I.
2010-03-01
The operation of atomic clocks is generally carried out at room temperature, whereas the definition of the second refers to the clock transition in an atom at absolute zero. This implies that the clock transition frequency should be corrected in practice for the effect of finite temperature of which the leading contributor is the blackbody radiation (BBR) shift. Experimental measurements of the BBR shifts are difficult. In this work, we have calculated the blackbody radiation shift of the ground-state hyperfine microwave transition in ^87Rb using the relativistic all-order method and evaluated the accuracy of our final value. Particular care is taken to accurately account for the contributions from highly-excited states. Various Rb atomic properties, including E1, E2, and E3 ground state polarizabilities, np and nd E1 polarizabilities, and hyperfine constants are also calculated. The results are compared with experiment and other theory where available.
Black-body radiation shift of the Ga$^{+}$ clock transition
Cheng, Yongjun
2013-01-01
The blackbody radiation shift of the Ga$^+$ $4s^2 \\ ^1S^e_0 \\to 4s4p \\ ^3P^o_0$ clock transition is computed to be $-$$0.0140 \\pm 0.0048$ Hz at 300 K. The small shift is consistent with the blackbody shifts of the clock transitions of other group III ions which are of a similar size. The polarizabilities of the Ga$^+$ $4s^2 \\ ^1S^e_0$, $4s4p \\ ^3P^o_0$, and $4s4p \\ ^1P^o_1$ states were computed using the configuration interaction method with an underlying semi-empirical core potential. A byproduct of the analysis involved large scale calculations of the low lying spectrum and oscillator strengths of the Ga$^{2+}$ ion.
Comparison of blackbodies for calibration of infrared ear thermometers
DEFF Research Database (Denmark)
Pusnik, Igor; Clausen, Sønnik; Favreau, Jacques-Olivier
2010-01-01
used for the calibration of IRETs among European national laboratories. To verify the accuracy of an IRET a suitable blackbody is needed. An essential requirement is related to accuracy. There are several standards in the world, which describe requirements for IRETs and a blackbody. In the EU...... this is the standard EN 12470-5, which is a harmonised standard and supports the Medical Device Directive (MDD). Other standards are ASTM standard, Designation E 1965 – 98 and the draft of Japan Industrial Standard JIS T 4207, 2005: Japanese Industrial Standard: “infrared ear thermometers.”. The International...... Organization for Standardization (ISO) is developing a new standard for clinical thermometers, which will include also IRETs. The basic requirement for accuracy in EN 12470-5 is that the maximum permissible error of IRET is ±0,2 °C in the range from 35,5 °C to 42,0 °C, while the uncertainty of a blackbody...
Satellite measurements of formaldehyde linked to shipping emissions
Directory of Open Access Journals (Sweden)
T. Wagner
2009-11-01
Full Text Available International shipping is recognized as a pollution source of growing importance, in particular in the remote marine boundary layer. Nitrogen dioxide originating from ship emissions has previously been detected in satellite measurements. This study presents the first satellite measurements of formaldehyde (HCHO linked to shipping emissions as derived from observations made by the Global Ozone Monitoring Experiment (GOME instrument.
We analyzed enhanced HCHO tropospheric columns from shipping emissions over the Indian Ocean between Sri Lanka and Sumatra. This region offers good conditions in term of plume detection with the GOME instrument as all ship tracks follow a single narrow track in the same east-west direction as used for the GOME pixel scanning. The HCHO signal alone is weak but could be clearly seen in the high-pass filtered data. The line of enhanced HCHO in the Indian Ocean as seen in the 7-year composite of cloud free GOME observations clearly coincides with the distinct ship track corridor from Sri Lanka to Indonesia. The observed mean HCHO column enhancement over this shipping route is about 2.0×10^{15} molec/cm^{2}.
Compared to the simultaneously observed NO_{2} values over the shipping route, those of HCHO are substantially higher; also the HCHO peaks are found at larger distance from the ship routes. These findings indicate that direct emissions of HCHO or degradation of emitted NMHC cannot explain the observed enhanced HCHO values. One possible reason might be increased CH_{4} degradation due to enhanced OH concentrations related to the ship emissions, but this source is probably too weak to fully explain the observed values.
The observed HCHO pattern also agrees qualitatively well with results from the coupled earth system model ECHAM5/MESSy applied to atmospheric chemistry (EMAC. However, the modelled HCHO values over the ship corridor are two times lower than in the
Global distribution of pauses observed with satellite measurements
Indian Academy of Sciences (India)
M Venkat Ratnam; P Kishore; Isabella Velicogna
2013-04-01
Several studies have been carried out on the tropopause, stratopause, and mesopause (collectively termed as ‘pauses’) independently; however, all the pauses have not been studied together. We present global distribution of altitudes and temperatures of these pauses observed with long-term space borne high resolution measurements of Global Positioning System (GPS) Radio Occultation (RO) and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) aboard Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics (TIMED) satellite. Here we study the commonality and differences observed in the variability of all the pauses. We also examined how good other datasets will represent these features among (and in between) different satellite measurements, re-analysis, and model data. Hemispheric differences observed in all the pauses are also reported. In addition, we show that asymmetries between northern and southern hemispheres continue up to the mesopause. We analyze inter and intra-seasonal variations and long-term trends of these pauses at different latitudes. Finally, a new reference temperature profile is shown from the ground to 110 km for tropical, mid-latitudes, and polar latitudes for both northern and southern hemispheres.
Air quality performed with satellite measurement within the QUITSAT project
Masieri, Samuele; Petritoli, Andrea; Premuda, Margarita; Kostadinov, Ivan; Bortoli, Daniele; Ravegnani, Fabrizio; Giovanelli, Giorgio
Ground pollutants monitoring, using satellite observation, represents an interesting and high potential approach to air quality that could be inserted into Global monitoring systems. The QUITSAT Italian pilot project (air QUality with Integration of ground based and SAtellite measurements and chemical Transport and multiphase model), funded by the Italian Space Agency (ASI), proposes a new approach producing some interesting results in this frame. The approach focuses in the integration of the satellite observations (ENVISAT/SCIAMACHY and AURA/OMI) with the outputs of the GAMES (Gas Aerosol Modelling Evaluation System) chemical transport model, to provide the evaluation of the tropospheric profiles of some atmo-spheric compounds such as NO2 , O3 , HCHO and SO2 . This activity appears to be very useful to retrieve the surface concentration of trace gases from tropospheric columns of atmospheric compounds obtained with satellite instrumentation. The comparison with the in situ analyzer network over the Po' Valley shows a good correlation between the two data set. The corre-spondence can be improved taking into account also concentration gradients between different stations, classifying the ground base stations according to their rural or urban characteristics and considering the general orography of the ground. Results and methodology are presented and discussed.
A history of slide rules for blackbody radiation computations
Johnson, R. Barry; Stewart, Sean M.
2012-10-01
During the Second World War the importance of utilizing detection devices capable of operating in the infrared portion of the electromagnetic spectrum was firmly established. Up until that time, laboriously constructed tables for blackbody radiation needed to be used in calculations involving the amount of radiation radiated within a given spectral region or for other related radiometric quantities. To rapidly achieve reasonably accurate calculations of such radiometric quantities, a blackbody radiation calculator was devised in slide rule form first in Germany in 1944 and soon after in England and the United States. In the immediate decades after its introduction, the radiation slide rule was widely adopted and recognized as a useful and important tool for engineers and scientists working in the infrared field. It reached its pinnacle in the United States in 1970 in a rule introduced by Electro Optical Industries, Inc. With the onset in the latter half of the 1970s of affordable, hand-held electronic calculators, the impending demise of the radiation slide rule was evident. No longer the calculational device of choice, the radiation slide rule all but disappeared within a few short years. Although today blackbody radiation calculations can be readily accomplished using anything from a programmable pocket calculator upwards, with each device making use of a wide variety of numerical approximations to the integral of Planck's function, radiation slide rules were in the early decades of infrared technology the definitive "workhorse" for those involved in infrared systems design and engineering. This paper presents a historical development of radiation slide rules with many versions being discussed.
Near-Blackbody Enclosed Particle-Receiver Development
Energy Technology Data Exchange (ETDEWEB)
Ma, Zhiwen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sakadjian, Bartev [Babcock and Wilcox Research Center, Charlotte, NC (United States)
2015-12-01
This 3-year project develops a technology using gas/solid, two-phase flow as a heat-transfer fluid and separated, stable, solid particles as a thermal energy storage (TES) medium for a concentrating solar power (CSP) plant, to address the temperature, efficiency, and cost barriers associated with current molten-salt CSP systems. This project focused on developing a near-blackbody particle receiver and an integrated fluidized-bed heat exchanger with auxiliary components to achieve greater than 20% cost reduction over current CSP plants, and to provide the ability to drive high-efficiency power cycles.
Equilibrium properties of blackbody radiation in Doubly Special Relativity
Chandra, Nitin; Vaibhav, Vinay
2016-01-01
Doubly Special Relativity (DSR) is an attempt to incorporate an observer independent energy/length scale in the relativistic theory. We study various thermodynamic properties of blackbody radiation in DSR. We find that the energy density, specific heat etc. follows usual acoustic phonon dynamics as has been well studied by Debye. Other thermodynamic quantities like pressure, entropy etc. has also been calculated. The usual Stefan-Boltzmann law gets modified. The phase-space measure is also expected to get modified for an exotic spacetime, which in turn leads to the modification of Planck energy density distribution and the Wien's displacement law.
Blackbody-induced radiative dissociation of cationic SF 6 clusters
DEFF Research Database (Denmark)
Toker, Jonathan; Rahinov, I.; Schwalm, D.;
2012-01-01
The stability of cationic SF5+(SF6)n−1 clusters was investigated by measuring their blackbody-induced radiative dissociation (BIRD) rates. The clusters were produced in a supersonic expansion ion source and stored in an electrostatic ion-beam trap at room temperature, where their abundances...... and lifetimes were measured. Using the “master equation” approach, relative binding energies of an SF6 unit in the clusters could be extracted from the storage-time dependence of the survival probabilities. The results allow for a deeper insight into the effect of a localized charge on the structure...... and stability of SF6-based clusters....
NIST Infrared Blackbody Calibration Support for Climate Change Research
Hanssen, L. M.; Zeng, J.; Mekhontsev, S.; Khromchenko, V.
2012-12-01
The National Institute of Technology (NIST) Sensor Science Division has established measurement capabilities in support of various existing and planned satellite programs, which monitor key parameters for the study of climate change, such as solar irradiance, earth radiance, and atmospheric effects. These capabilities include the characterization of infrared reference blackbody sources and cavity radiometers, as well as the materials used to coat the cavity surfaces. In order to accurately measure high levels of effective emissivity and absorptance of cavities, NIST has developed a laser- and integrating-sphere-based facility (the Complete Hemispherical Infrared Laser-based Reflectometer (CHILR)). The system is used for both radiometer and blackbody cavity characterization. Multiple laser sources with wavelengths ranging from 1.5 μm to 23 μm are used to perform reflectance (1 - emissivity (or absorptance)) measurements of radiometer cavities. Measurements have been performed for numerous instruments including the Internal Calibration Target (ICT)) blackbody source used for calibration of the Cross track Infrared Sounder (CrIS), and the Total Irradiance Monitor (TIM) instrument on the Solar Radiation and Climate Experiment (SORCE), both for the Joint Polar Satellite System (JPSS), as well as the Active Cavity Radiometer Irradiance Monitor (ACRIM) instrument, and blackbodies constructed for prototyping of an infrared instrument on the Climate Absolute Radiance and Refractivity Observatory (CLARREO). For a more comprehensive understanding of the measurement results, NIST has also measured samples of the coated surfaces of the cavities and associated baffles. This includes several types of reflectance measurements: specular, directional-hemispherical (diffuse), and bi-directional distribution function (BRDF). The first two are performed spectrally and provide information that enables estimation of the cavity performance where laser sources for CHILR are not available
Design and construction of a gallium fixed-point blackbody at CENAM
Energy Technology Data Exchange (ETDEWEB)
Cardenas G, D., E-mail: dcardena@cenam.mx [Centro Nacional de Metrologia, Km 4.5 Carretera a los Cues, El Marques, 76246 Santiago de Queretaro, Queretaro (Mexico)
2015-07-01
For temperatures below silver fixed-point defined by the International Temperature Scale of 1990, a transfer radiation thermometer can be calibrated using either of two calibration schemes: a variable temperature blackbody with a standard platinum resistance thermometer as a reference, or with a set of fixed-point blackbodies. CENAM is presently working with the first scheme, and it is developing fixed-point blackbodies to have the capability to work with the second scheme too. For this purpose a gallium fixed-point blackbody to calibrate CENAM transfer radiation thermometer was designed and constructed. The blackbody cavity has a cylinder-cone shape with effective emissivity equal to 0.9992±0.0004 in the 8 μm to 14 μm wavelength range. The radiance temperature of the gallium fixed-point blackbody was estimated to have and expanded uncertainty of 54 m K, with a coverage factor k = 2. (Author)
Optimising Blackbody Cavity Shape for Spatially Uniform Integrated Emissivity
Saunders, P.
2017-01-01
The emissivity of a blackbody cavity, as seen by a radiation thermometer viewing the cavity, depends on both the field of view of the thermometer and the distribution of local effective emissivity values within the field of view. For cylindro-conical cavities, the local effective emissivity generally attains a maximum value at the apex of the cone and drops along the conical section. Thus, radiation thermometers with different fields of view see different blackbody emissivity values. This impacts, particularly, on the calibration of wide-angle low-temperature radiation thermometers and thermal imaging systems where each pixel responds to a different radiance. The spatial uniformity of the effective emissivity profile depends principally on the cone angle, with a weaker dependence on the length-to-diameter ratio of the cavity, the intrinsic emissivity of the cavity surfaces, and the temperature gradient along the cavity. In this paper, a nonlinear least-squares method is used to determine the optimal cone angle as a function of the cavity parameters. It is concluded that full cone angles close to 160° provide the flattest effective emissivity profile across the conical section of the cavity for typical cavity parameters. A method is also described for calculating the value of integrated emissivity, which includes the umbral and penumbral regions seen by an imaging radiation thermometer.
Measurements of Martin-Puplett Interferometer Limitations using Blackbody Source
Energy Technology Data Exchange (ETDEWEB)
Evtushenko, Pavel E. [JLAB; Klopf, John M. [JLAB
2013-06-01
Frequency domain measurements with Martin-Puplett interferometer is one of a few techniques capable of bunch length measurements at the level of ~ 100 fs. As the bunch length becomes shorter, it is important to know and be able to measure the limitations of the instrument in terms of shortest measurable bunch length. In this paper we describe an experiment using a blackbody source with the modified Martin-Puplett interferometer that is routine- ly used for bunch length measurements at the JLab FEL, as a way to estimate the shortest, measurable bunch length. The limitation comes from high frequency cut-off of the wire-grid polarizer currently used and is estimated to be 50 fs RMS. The measurements are made with the same Golay cell detector that is used for beam measure- ments. We demonstrate that, even though the blackbody source is many orders of magnitude less bright than the coherent transition or synchrotron radiation, it can be used for the measurements and gives a very good signal to noise ratio in combination with lock-in detection. We also compare the measurements made in air and in vacuum to characterize the very strong effect of the atmospheric absorption.
Calibration and investigation of infrared camera systems applying blackbody radiation
Hartmann, Juergen; Fischer, Joachim
2001-03-01
An experimental facility is presented, which allows calibration and detailed investigation of infrared camera systems. Various blackbodies operating in the temperature range from -60 degree(s)C up to 3000 degree(s)C serve as standard radiation sources, enabling calibration of camera systems in a wide temperature and spectral range with highest accuracy. Quantitative results and precise long-term investigations, especially in detecting climatic trends, require accurate traceability to the International Temperature Scale of 1990 (ITS-90). For the used blackbodies the traceability to ITS- 90 is either realized by standard platinum resistance thermometers (in the temperature range below 962 degree(s)C) or by absolute and relative radiometry (in the temperature range above 962 degree(s)C). This traceability is fundamental for implementation of quality assurance systems and realization of different standardizations, for example according ISO 9000. For investigation of the angular and the temperature resolution our set-up enables minimum resolvable (MRTD) and minimum detectable temperature difference (MDTD) measurements in the various temperature ranges. A collimator system may be used to image the MRTD and MDTD targets to infinity. As internal calibration of infrared camera systems critically depends on the temperature of the surrounding, the calibration and investigation of the cameras is performed in a climate box, which allows a detailed controlling of the environmental parameters like humidity and temperature. Experimental results obtained for different camera systems are presented and discussed.
Blackbody radiation shift in the Rb87 frequency standard
Safronova, M. S.; Jiang, Dansha; Safronova, U. I.
2010-08-01
The operation of atomic clocks is generally carried out at room temperature, whereas the definition of the second refers to the clock transition in an atom at absolute zero. This implies that the clock transition frequency should be corrected in practice for the effect of finite temperature, of which the leading contributor is the blackbody radiation (BBR) shift. Experimental measurements of the BBR shifts are difficult. In this work, we have calculated the blackbody radiation shift of the ground-state hyperfine microwave transition in Rb87 using the relativistic all-order method and carried out a detailed evaluation of the accuracy of our final value. Particular care is taken to accurately account for the contributions from highly excited states. Our predicted value for the Stark coefficient, kS=-1.240(4)×10-10Hz/(V/m)2, is three times more accurate than the previous calculation [E. J. Angstman, V. A. Dzuba, and V. V. Flambaum, Phys. Rev. APLRAAN1050-294710.1103/PhysRevA.74.023405 74, 023405 (2006)].
Black-body anomaly: analysis of temperature offsets
Szopa, M.; Hofmann, R.; Giacosa, F.; Schwarz, M.
2008-04-01
Based on the postulate that photon propagation is governed by a dynamically broken SU(2) gauge symmetry (scale ˜10-4 eV) we make predictions for temperature offsets due to a low-temperature (a few times the present CMB temperature) spectral anomaly at low frequencies. Temperature offsets are extracted from least-square fits of the anomalous black-body spectra to their conventional counterparts. We discuss statistical errors, compare our results with those obtained from calibration data of the FIRAS instrument, and point out that our predicted offsets are screened by experimental errors given the frequency range used by FIRAS to perform their spectral fits. We also make contact with the WMAP observation by blueshifting their frequency bands. Although our results hint towards a strong dynamical component in the CMB dipole and an explanation of low-l suppression, it is important in view of its particle-physics implications that the above postulate be verified/falsified by an independent low-temperature black-body precision experiment.
Are GRB Blackbodies an Artifact of Spectral Evolution?
Burgess, J Michael
2014-01-01
The analysis of gamma-ray burst (GRB) spectra with multi-component emission models has become an important part of the field. In particular, multi-component analysis where one component is a blackbody representing emission from a photosphere has enabled both a more detailed understanding of the energy content of the jet as well as the ability to examine the dynamic structure of the outflow. While the existence of a blackbody-like component has been shown to be significant and not a byproduct of background fluctuations, it is very possible that it can be an artifact of spectral evolution of a single component that is being poorly resolved in time. Herein, this possibility is tested by simulating a single component evolving in time and then folding the spectra through the $Fermi$ detector response to generate time-tagged event Gamma-ray Burst Monitor (GBM) data. We then fit both the time integrated and resolved generated spectral data with a multi-component model using standard tools. It is found that in {\\it t...
Anomalously small blackbody radiation shift in Tl+ frequency standard
Zuhrianda, Z; Kozlov, M G
2012-01-01
The operation of atomic clocks is generally carried out at room temperature, whereas the definition of the second refers to the clock transition in an atom at absolute zero. This implies that the clock transition frequency should be corrected in practice for the effect of finite temperature of which the leading contributor is the blackbody radiation (BBR) shift. In the present work, we used configuration interaction + coupled-cluster method to evaluate polarizabilities of the $6s^2 ^1S_0$ and $6s6p ^3P_0$ states of Tl$^+$ ion; we find $\\alpha_0(^1S_0)=19.6$ a.u. and $\\alpha_0(^3P_0)=21.4$ a.u.. The resulting BBR shift of the $6s6p ^3P_0 - 6s^2 ^1S_0$ Tl$^+$ transition at $300 K$ is $\\Delta \
The isotropic blackbody CMB as evidence for a homogeneous universe
Clifton, Timothy; Bull, Philip
2011-01-01
The question of whether the Universe is spatially homogeneous and isotropic on the largest scales is of fundamental importance to cosmology, but has not yet been answered decisively. Surprisingly, neither an isotropic primary CMB nor combined observations of luminosity distances and galaxy number counts are sufficient to establish such a result. The inclusion of the Sunyaev-Zel'dovich effect in CMB observations, however, dramatically improves this situation. We show that even a solitary observer who sees an isotropic blackbody CMB can conclude that the universe is homogeneous and isotropic in their causal past when the Sunyaev-Zel'dovich effect is present. Critically, however, the CMB must either be viewed for an extended period of time, or CMB photons that have scattered more than once must be detected. This result provides a theoretical underpinning for testing the Cosmological Principle with observations of the CMB alone.
Miniature High Stability High Temperature Space Rated Blackbody Radiance Source
Jones, J. A.; Beswick, A. G.
1987-09-01
This paper presents the design and test performance of a conical cavity type blackbody radiance source that will meet the requirements of the Halogen Occultation Experiment (HALOE) on the NASA Upper Atmospheric Research Satellite program (UARS). Since a radiance source meeting the requirements of this experiment was unavailable in the commercial market, a development effort was undertaken by the HALOE Project. The blackbody radiance source operates in vacuum at 1300 K + 0.5 K over any 15-minute interval, uses less than 7.5 watts of power, maintains a 49°C outer case temperature, and fits within the 2.5 x 2.5 x 3.0 inch envelope allocated inside the HALOE instrument. Also, the unit operates in air, during ground testing of the HALOE instrument, where it uses 17 watts of power with an outer case temperature of 66°C. The thrust of this design effort was to minimize the heat losses, in order to keep the power usage under 7.5 watts, and to minimize the amount of silica in the materials. Silica in the presence of the platinum heater winding used in this design would cause the platinum to erode, changing the operating temperature set-point. The design required the development of fabrication techniques which would provide very small, close tolerance parts from extremely difficult-to-machine materials. Also, a space rated ceramic core and unique, low thermal conductance, ceramic-to-metal joint was developed, tested and incorporated in this design. The completed flight qualification hardware has undergone performance, environmental and life testing. The design configuration and test results are discussed in detail in this paper.
Breaking the black-body limit with resonant surfaces
Directory of Open Access Journals (Sweden)
Valagiannopoulos Constantinos A.
2017-01-01
Full Text Available The speed with which electromagnetic energy can be wirelessly transferred from a source to the user is a crucial indicator for the performance of a large number of electronic and photonic devices. We expect that energy transfer can be enhanced using special materials. In this paper, we determine the constituent parameters of a medium which can support theoretically infinite energy concentration close to its boundary; such a material combines properties of Perfectly Matched Layers (PML and Double-Negative (DNG media. It realizes conjugate matching with free space for every possible mode including, most importantly, all evanescent modes; we call this medium Conjugate Matched Layer (CML. Sources located outside such layer deliver power to the conjugate-matched body exceptionally effectively, impressively overcoming the black-body absorption limit which takes into account only propagating waves. We also expand this near-field concept related to the infinitely fast absorption of energy along the air-medium interface to enhance the far-field radiation. This becomes possible with the use of small particles randomly placed along the boundary; the induced currents due to the extremely high-amplitude resonating fields can play the role of emission “vessels”, by sending part of the theoretically unlimited near-field energy far away from the CML structure.
CMB all-scale blackbody distortions induced by linearizing temperature
Notari, Alessio; Quartin, Miguel
2016-08-01
Cosmic microwave background (CMB) experiments, such as WMAP and Planck, measure intensity anisotropies and build maps using a linearized formula for relating them to the temperature blackbody fluctuations. However, this procedure also generates a signal in the maps in the form of y -type distortions which is degenerate with the thermal Sunyaev Zel'dovich (tSZ) effect. These are small effects that arise at second order in the temperature fluctuations not from primordial physics but from such a limitation of the map-making procedure. They constitute a contaminant for measurements of our peculiar velocity, the tSZ and primordial y -distortions. They can nevertheless be well modeled and accounted for. We show that the distortions arise from a leakage of the CMB dipole into the y -channel which couples to all multipoles, mostly affecting the range ℓ≲400 . This should be visible in Planck's y -maps with an estimated signal-to-noise ratio of about 12. We note however that such frequency-dependent terms carry no new information on the nature of the CMB dipole. This implies that the real significance of Planck's Doppler coupling measurements is actually lower than reported by the collaboration. Finally, we quantify the level of contamination in tSZ and primordial y -type distortions and show that it is above the sensitivity of proposed next-generation CMB experiments.
Blackbody radiation: rosetta stone of heat bath models
O'Connell, R. F.
2007-06-01
The radiation field can be regarded as a collection of independent harmonic oscillators and, as such, constitutes a heat bath. Moreover, the known form of its interaction with charged particles provides a "rosetta stone" for deciding on and interpreting the correct interaction for the more general case of a quantum particle in an external potential and coupled to an arbitrary heat bath. In particular, combining QED with the machinery of stochastic physics, enables the usual scope of applications to be widened. We discuss blackbody radiation effects on: the equation of motion of a radiating electron (obtaining an equation of motion which is free from runaway solutions), anomalous diffusion, the spreading of a Gaussian wave packet, and decoherence effects due to zero-point oscillations. In addition, utilizing a formula we obtained for the free energy of an oscillator in a heat bath, enables us to determine all the quantum thermodynamic functions of interest (particularly in the areas of quantum information and nanophysics where small systems are involved) and from which we obtain temperature dependent Lamb shifts, quantum effects on the entropy at low temperature and implications for Nernst's law.
Black-Body Anomaly: Analysis of Temperature Offsets
Szopa, Michal; Giacosa, Francesco; Schwarz, Markus
2007-01-01
Based on the postulate that photon propagation is governed by a dynamically broken SU(2) gauge symmetry (scale $\\sim 10^{-4} $eV) we make predictions for temperature offsets due to a low-temperature (a few times the present CMB temperature) spectral anomaly at low frequencies. Temperature offsets are extracted from least-square fits of the anomalous black-body spectra to their conventional counterparts. We discuss statistical errors, compare our results with those obtained from calibration data of the FIRAS instrument, and point out that our predicted offsets are screened by experimental errors given the frequency range used by FIRAS to perform their spectral fits. We also make contact with the WMAP observation by blueshifting their frequency bands. Although our results hint towards a strong dynamical component in the CMB dipole and an explanation of low-$l$ suppression it is important in view of its particle-physics implications that the above postulate be verified/falsified by an independent low-temperature...
CMB all-scale blackbody distortions induced by linearizing temperature
Notari, Alessio
2016-01-01
Cosmic Microwave Background (CMB) experiments, such as WMAP and Planck, measure intensity anisotropies and build maps using a \\emph{linearized} formula for relating them to the temperature blackbody fluctuations. However such a procedure also generates a signal in the maps in the form of y-type distortions, and thus degenerate with the thermal SZ (tSZ) effect. These are small effects that arise at second-order in the temperature fluctuations not from primordial physics but from such a limitation of the map-making procedure. They constitute a contaminant for measurements of: our peculiar velocity, the tSZ and of primordial y-distortions, but they can nevertheless be well-modelled and accounted for. We show that the largest distortions arises at high ell from a leakage of the CMB dipole into the y-channel which couples to all multipoles, but mostly affects the range ell <~ 400. This should be visible in Planck's y-maps with an estimated signal-to-noise ratio of about 9. We note however that such frequency-de...
The Fermilab Large Cold Blackbody Test Stand for CMB R&D
Energy Technology Data Exchange (ETDEWEB)
Kubik, Donna [Fermilab; Butler, D. [Fermilab; DeJongh, F. [Fermilab; Korienek, J. [Fermilab; Lindenmeyer, C. [Fermilab; Montes, J. [Fermilab; Nguyen, H. [Fermilab; Wilson, J. [Fermilab
2012-03-18
The Fermilab Large Cold Blackbody Test Stand can be used to expose a microwave receiver and horn assembly to a large blackbody at cryogenic temperatures (as low as 20 K). The temperature of the blackbody can be varied while keeping the receiver temperature constant, facilitating Y-factor measurements of the receiver noise temperature and gain. The test stand has recently been used for studying a QUIET-I receiver module. The test stand will be used to measure both QUIET-I and prototype QUIET-II modules.
Onboard Blackbody Calibrator Component Development for IR Remote Sensing Instrumentation Project
National Aeronautics and Space Administration — We plan to develop a blackbody coated with Carbon nanotube materials that will able to operate in the temperature ranges need to calibrate a thermal infrared sensor...
Anomalously small blackbody radiation shift in the Tl+ frequency standard
Zuhrianda, Z.; Safronova, M. S.; Kozlov, M. G.
2012-02-01
The operation of atomic clocks is generally carried out at room temperature, whereas the definition of the second refers to the clock transition in an atom at absolute zero. This implies that the clock transition frequency should be corrected in practice for the effect of finite temperature of which the leading contributor is the blackbody radiation (BBR) shift. In the present work, we used configuration interaction + coupled-cluster method to evaluate polarizabilities of the 6s21S0 and 6s6p3P0 states of the Tl+ ion; we find α0(1S0)=19.6 a.u. and α0(3P0)=21.4 a.u. The resulting BBR shift of the 6s6p3P0-6s21S0 Tl+ transition at 300 K is ΔνBBR=-0.0157(16) Hz. This result demonstrates that near cancellation of the 1S0 and 3P0 state polarizabilities in divalent B+, Al+, and In+ ions of group IIIB [M. S. Safronova , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.107.143006 107, 143006 (2011)] continues for much heavier Tl+, leading to anomalously small BBR shift for this system. This calculation demonstrates that the BBR contribution to the fractional frequency uncertainty of the Tl+ frequency standard at 300 K is 1×10-18. We find that Tl+ has the smallest fractional BBR shift among all present or proposed frequency standards with the exception of Al+.
Was The Electromagnetic Spectrum A Blackbody Spectrum In The Early Universe?
Opher, Merav; Opher,Reuven
1997-01-01
It is assumed, in general, that the electromagnetic spectrum in the Primordial Universe was a blackbody spectrum in vacuum. We derive the electromagnetic spectrum, based on the Fluctuation-Dissipation Theorem that describes the electromagnetic fluctuations in a plasma. Our description includes thermal and collisional effects in a plasma. The electromagnetic spectrum obtained differs from the blackbody spectrum in vacuum at low frequencies. In particular, concentrating on the primordial nucleo...
Variable Temperature Blackbodies via Variable Conductance: Thermal Design, Modelling and Testing
Melzack, N.; Jones, E.; Peters, D. M.; Hurley, J. G.; Watkins, R. E. J.; Fok, S.; Sawyer, C.; Marchetaux, G.; Acreman, A.; Winkler, R.; Lowe, D.; Theocharous, T.; Montag, V.; Gibbs, D.; Pearce, A. B.; Bishop, G.; Newman, E.; Keen, S.; Stokes, J.; Pearce, A.; Stamper, R.; Cantell-Hynes, A.
2017-02-01
This paper presents the overall design for large (˜ 400 mm aperture) reference blackbody cavities currently under development at the Science and Technology Facilities Council Rutherford Appleton Laboratory Space Department (STFC RAL Space), in collaboration with the National Physical Laboratory (NPL). These blackbodies are designed to operate in vacuum over a temperature range from 160 K to 370 K, with an additional capability to operate at ˜ 100 K as a point of near-zero radiance. This is a challenging problem for a single blackbody. The novel thermal design presented in this paper enables one target that can physically achieve and operate successfully at both thermal extremes, whilst also meeting stringent temperature gradient requirements. The overall blackbody design is based upon a helium gas-gap heat switch and modified to allow for variable thermal conductance. The blackbody design consists of three main concentric cylinder components—an inner cavity (aluminium alloy), a radiation shield (aluminium) and an outer liquid nitrogen (LN2) jacket (stainless steel). The internal surface of the cavity is the effective radiating surface. There is a helium gas interspace surrounding the radiation shield and enclosed by the LN2 jacket and the inner cavity. The blackbodies are now at a mature stage of development. In this paper, the overall design, focusing upon the thermal design solution, is detailed. This paper will also concern the full-scale prototype breadboard model, for which results on thermal stability, spatial gradients and other sensitivities will be presented.
Energy Technology Data Exchange (ETDEWEB)
Parra, Felix I; Catto, Peter J [Plasma Science and Fusion Center, MIT, Cambridge, MA 02139 (United States)], E-mail: fparra@mit.edu, E-mail: catto@psfc.mit.edu
2009-06-15
We compare two different derivations of the gyrokinetic equation: the Hamiltonian approach in Dubin D H E et al (1983 Phys. Fluids 26 3524) and the recursive methodology in Parra F I and Catto P J (2008 Plasma Phys. Control. Fusion 50 065014). We prove that both approaches yield the same result at least to second order in a Larmor radius over macroscopic length expansion. There are subtle differences in the definitions of some of the functions that need to be taken into account to prove the equivalence.
Parra, Felix I.; Catto, Peter J.
2009-06-01
We compare two different derivations of the gyrokinetic equation: the Hamiltonian approach in Dubin D H E et al (1983 Phys. Fluids 26 3524) and the recursive methodology in Parra F I and Catto P J (2008 Plasma Phys. Control. Fusion 50 065014). We prove that both approaches yield the same result at least to second order in a Larmor radius over macroscopic length expansion. There are subtle differences in the definitions of some of the functions that need to be taken into account to prove the equivalence.
Lukasevich, V. I.; Kramarov, S. O.; Sokolov, Sergey V.
2015-01-01
It is solved a problem of a posteriori estimation of dynamically modified parameters of angular movement of the object by satellite measurements. There are shown advantages of application of the methods of stochastic non-linear dynamic filtration before single-stage measurements. It is represented an example, showing efficiency of proposed approach.
Boyer, Timothy H.
2016-11-01
Electromagnetism is a relativistic theory, and one must exercise care in coupling this theory with nonrelativistic classical mechanics and with nonrelativistic classical statistical mechanics. Indeed historically, both the blackbody radiation spectrum and diamagnetism within classical theory have been misunderstood because of two crucial failures: (1) the neglect of classical electromagnetic zero-point radiation, and (2) the use of erroneous combinations of nonrelativistic mechanics with relativistic electrodynamics. Here we review the treatment of classical blackbody radiation, and show that the presence of Lorentz-invariant classical electromagnetic zero-point radiation can explain both the Planck blackbody spectrum and Landau diamagnetism at thermal equilibrium within classical electromagnetic theory. The analysis requires that relativistic electromagnetism is joined appropriately with simple nonrelativistic mechanical systems which can be regarded as the zero-velocity limits of relativistic systems, and that nonrelativistic classical statistical mechanics is applied only in the low-frequency limit when zero-point energy makes no contribution.
Zhang, M.; Lin, W.; Klein, S.; J. Bacmeister; Bony, S.; Cederwall, R.; Del Genio, A; Hack, J.; Loeb, N.; Lohmann, U.; P. Minnis; Musat, I.; Pincus, R; Stier, P.; Suarez, M.
2005-01-01
To assess the current status of climate models in simulating clouds, basic cloud climatologies from ten atmospheric general circulation models are compared with satellite measurements from the International Satellite Cloud Climatology Project (ISCCP) and the Clouds and Earth's Radiant Energy System (CERES) program. An ISCCP simulator is employed in all models to facilitate the comparison. Models simulated a four-fold difference in high-top clouds. There are also, however, large uncertainties ...
Black-body radiation for twist-deformed space-time
Daszkiewicz, Marcin
2015-01-01
In this article we formally investigate the impact of twisted space-time on black-body radiation phenomena, i.e. we derive the $\\theta$-deformed Planck distribution function as well as we perform its numerical integration to the $\\theta$-deformed total radiation energy. In such a way we indicate that the space-time noncommutativity very strongly damps the black-body radiation process. Besides we provide for small parameter $\\theta$ the twisted counterparts of Rayleigh-Jeans and Wien distributions respectively.
Analysis of the blackbody-radiation shift in an ytterbium optical lattice clock
Xu, Yi-Lin; Xu, Xin-Ye
2016-10-01
We accurately evaluate the blackbody-radiation shift in a 171Yb optical lattice clock by utilizing temperature measurement and numerical simulation. In this work. three main radiation sources are considered for the blackbody-radiation shift, including the heated atomic oven, the warm vacuum chamber, and the room-temperature vacuum windows. The temperatures on the outer surface of the vacuum chamber are measured during the clock operation period by utilizing seven calibrated temperature sensors. Then we infer the temperature distribution inside the vacuum chamber by numerical simulation according to the measured temperatures. Furthermore, we simulate the temperature variation around the cold atoms while the environmental temperature is fluctuating. Finally, we obtain that the total blackbody-radiation shift is -1.289(7) Hz with an uncertainty of 1.25 × 10-17 for our 171Yb optical lattice clock. The presented method is quite suitable for accurately evaluating the blackbody-radiation shift of the optical lattice clock in the case of lacking the sensors inside the vacuum chamber. Project supported by the National Key Basic Research and Development Program of China (Grant No. 2012CB821302), the National Natural Science Foundation of China (Grant No. 11134003), the National High Technology Research and Development Program of China (Grant No. 2014AA123401), and the Shanghai Excellent Academic Leaders Program of China (Grant No. 12XD1402400).
Institute of Scientific and Technical Information of China (English)
孙贝
2013-01-01
Equivalence, a central and controversial issue in translation, has been studied, discussed and disputed by many scholars. For this reason, they employed various approaches and have yielded fruitful and remarkable theories. Three representative equivalence theories are selected in the thesis to elaborate equivalence:Nida’s reader-response based dynamic equivalence, Catford’s textual equivalence, Qiu Maoru’s empirical formula on equivalence. Equivalence is an applicable tool to analyze and evaluate translation.
Analysis of the role of urban vegetation in local climate of Budapest using satellite measurements
Pongracz, Rita; Bartholy, Judit; Dezso, Zsuzsanna; Fricke, Cathy
2016-08-01
Urban areas significantly modify the natural environment due to the concentrated presence of humans and the associated anthropogenic activities. In order to assess this effect, it is essential to evaluate the relationship between urban and vegetated surface covers. In our study we focused on the Hungarian capital, Budapest, in which about 1.7 million inhabitants are living nowadays. The entire city is divided by the river Danube into the hilly, greener Buda side on the west, and the flat, more densely built-up Pest side on the east. Most of the extended urban vegetation, i.e., forests are located in the western Buda side. The effects of the past changing of these green areas are analyzed using surface temperature data calculated from satellite measurements in the infrared channels, and NDVI (Normalized Difference Vegetation Index) derived from visible and near-infrared satellite measurements. For this purpose, data available from sensor MODIS (Moderate Resolution Imaging Spectroradiometer) of NASA satellites (i.e., Terra and Aqua) are used. First, the climatological effects of forests on the urban heat island intensity are evaluated. Then, we also aim to evaluate the relationship of surface temperature and NDVI in this urban environment with special focus on vegetation-related sections of the city where the vegetation cover either increased or decreased remarkably.
Entropy and complexity properties of the d-dimensional blackbody radiation
Toranzo, I V
2015-01-01
Space dimensionality is a crucial variable in the analysis of the structure and dynamics of natural systems and phenomena. The dimensionality effects of the blackbody radiation has been the subject of considerable research activity in recent years. These studies are still somewhat fragmentary, pos- ing formidable qualitative and quantitative problems for various scientific and technological areas. In this work we carry out an information-theoretical analysis of the spectral energy density of a d-dimensional blackbody at temperature T by means of various entropy-like quantities (disequilibrium, Shannon entropy, Fisher information) as well as by three (dimensionless) complexity measures (Cr\\'amer-Rao, Fisher-Shannon and LMC). All these frequency-functional quantities are calculated and discussed in terms of temperature and dimensionality. It is shown that all three measures of complexity have an universal character in the sense that they depend neither on temperature nor on the Planck and Boltzmann constants, b...
Radiative cooling of solar absorbers using a visibly transparent photonic crystal thermal blackbody.
Zhu, Linxiao; Raman, Aaswath P; Fan, Shanhui
2015-10-06
A solar absorber, under the sun, is heated up by sunlight. In many applications, including solar cells and outdoor structures, the absorption of sunlight is intrinsic for either operational or aesthetic considerations, but the resulting heating is undesirable. Because a solar absorber by necessity faces the sky, it also naturally has radiative access to the coldness of the universe. Therefore, in these applications it would be very attractive to directly use the sky as a heat sink while preserving solar absorption properties. Here we experimentally demonstrate a visibly transparent thermal blackbody, based on a silica photonic crystal. When placed on a silicon absorber under sunlight, such a blackbody preserves or even slightly enhances sunlight absorption, but reduces the temperature of the underlying silicon absorber by as much as 13 °C due to radiative cooling. Our work shows that the concept of radiative cooling can be used in combination with the utilization of sunlight, enabling new technological capabilities.
Amoroso, Richard
2004-05-01
A blackbody equilibrium cavity QED theory for CMBR as emission and non-Doppler redshift as absorption is formulated utilizing an advanced form of Einstein's steady state cosmology. This Continuous State Universe (CSU) is based on a highly ordered periodic superspace that includes an energy dependent spacetime metric. The formalism for the superspace is derived by extending the Wheeler-Feynman absorber theory of radiation to the topology of the 12D periodic superspace. A fundamental least unit contains a core of Dirac spherical rotation with an inherent continuous compactification and dimensional reduction. It is shown formally that parameters of this cosmology demonstrate blackbody equilibrium conditions compatible with modes of emission and absorption suitable for describing CMBR and non-Doppler redshift.
Yu, Zongfu; Zhang, Torbjorn Skauli Gang; Wang, Hailiang; Fan, Shanhui
2012-01-01
The understanding of far-field thermal radiation had directly led to the discovery of quantum mechanics a century ago, and is of great current practical importance for applications in energy conversions, radiative cooling, and thermal control. It is commonly assumed that for any macroscopic thermal emitter, its maximal emitted power within any given frequency range cannot exceed that of a blackbody with the same surface area. In contrast to such conventional wisdom, here we propose, and experimentally demonstrate, that the emitted power from a finite size macroscopic blackbody to far field vacuum can be significantly enhanced, within the constraint of the second law of thermodynamics. To achieve such an enhancement, the thermal body needs to have internal electromagnetic density of states (DOS) greater than that of vacuum, and one needs to provide a thermal extraction mechanism to enable the contributions of all internal modes to far field radiation.
Laser-trapping of Ra-225 and Ra-226 with repumping by room temperature blackbody radiation
Guest, J R; Bailey, K; Greene, J P; Holt, R J; Lu, Z T; O'Connor, T P; Potterveld, D H; Scielzo, N D
2007-01-01
We have demonstrated Zeeman slowing and capture of neutral Ra-225 and Ra-226 atoms in a magneto-optical trap (MOT). The intercombination transition 1S0-3P1 is the only quasi-cycling transition in radium and was used for laser-cooling and trapping. Repumping along the 3D1-1P1 transition extended the lifetime of the trap from milliseconds to seconds. Room-temperature blackbody radiation was demonstrated to provide repumping from the metastable 3P0 level. We measured the isotope shift and hyperfine splittings on the 3D1-1P1 transition with the laser-cooled atoms, and set a limit on the lifetime of the 3D1 level based on the measured blackbody repumping rate. Laser-cooled and trapped radium is an attractive system for studying fundamental symmetries.
Effective emissivity of a blackbody cavity formed by two coaxial tubes.
Mei, Guohui; Zhang, Jiu; Zhao, Shumao; Xie, Zhi
2014-04-10
A blackbody cavity is developed for continuously measuring the temperature of molten steel, which consists of a cylindrical outer tube with a flat bottom, a coaxial inner tube, and an aperture diaphragm. The ray-tracing approach based on the Monte Carlo method was applied to calculate the effective emissivity for the isothermal cavity with the diffuse walls. And the dependences of the effective emissivity on the inner tube relative length were calculated for various inner tube radii, outer tube lengths, and wall emissivities. Results indicate that the effective emissivity usually has a maximum corresponding to the inner tube relative length, which can be explained by the impact of the inner tube relative length on the probability of the rays absorbed after two reflections. Thus, these results are helpful to the optimal design of the blackbody cavity.
Janssen, R M J; de Visser, P J; Klapwijk, T M; Baselmans, J J A
2014-01-01
We have measured and compared the response of hybrid NbTiN-Al Microwave Kinetic Inductance Detectors (MKIDs) to changes in bath temperature and illumination by sub-mm radiation. We show that these two stimulants have an equivalent effect on the resonance feature of hybrid MKIDs. We determine an electrical NEP from the measured temperature responsivity, quasiparticle recombination time, superconducting transition temperature and noise spectrum, all of which can be measured in a dark environment. For the two hybrid NbTiN-Al MKIDs studied in detail the electrical NEP is within a factor of two of the optical NEP, which is measured directly using a blackbody source.
Fermi golden rule for $N$-body systems in a black-body radiation
Ostilli, Massimo
2016-01-01
We review the calculation of the Fermi golden rule for a system of $N$-body dipoles, magnetic or electric, weakly interacting with a black-body radiation. By using the magnetic or electric field-field correlation function evaluated in the 1960s for the black body radiation, we deduce a general formula for the transition rates and study its limiting, fully coherent or fully incoherent, regimes.
Ballistic Diffusion of a Charged Particle in a Blackbody Radiation Field
Institute of Scientific and Technical Information of China (English)
BAO Jing-Dong; BAI Zhan-Wu
2005-01-01
@@ The generalized Langevin equation is used to describe the motion of a charged particle interacting with a blackbody radiation field via dipole coupling. The exact expressions for the mean-square displacement and velocity of such a particle are obtained, which show a ballistic diffusion and a modified Kubo fluctuation-dissipation relation. In particular, a velocity-dependent coupling or force can induce this novel phenomenon.
Matsumoto, Takahiro; Koizumi, Tomoaki; Kawakami, Yasuyuki; Okamoto, Koichi; Tomita, Makoto
2013-12-16
We report the successful fabrication of a novel type of blackbody material based on a graphene nanostructure. We demonstrate that the graphene nanostructure not only shows a low reflectance comparable to that of a carbon nanotube array but also shows an extremely high heat resistance at temperatures greater than 2500 K. The graphene nanostructure, which has an emissivity higher than 0.99 over a wide range of wavelengths, behaves as a standard blackbody material; therefore, the radiation spectrum and the temperature can be precisely measured in a simple manner. Here, the spectral emissivities of tungsten and tantalum are experimentally obtained using this ideal blackbody material and are compared to previously reported spectra. We clearly demonstrate the existence of a temperature-independent fixed point of emissivity at a certain wavelength. Both the spectral emissivity as a function of temperature and the cross-over point in the emissivity spectrum are well described by the complex dielectric function based on the Lorentz-Drude model with the phonon-scattering effect.
Night sky brightness at sites from DMSP-OLS satellite measurements
Cinzano, P
2004-01-01
We apply the sky brightness modelling technique introduced and developed by Roy Garstang to high-resolution DMSP-OLS satellite measurements of upward artificial light flux and to GTOPO30 digital elevation data in order to predict the brightness distribution of the night sky at a given site in the primary astronomical photometric bands for a range of atmospheric aerosol contents. This method, based on global data and accounting for elevation, Earth curvature and mountain screening, allows the evaluation of sky glow conditions over the entire sky for any site in the World, to evaluate its evolution, to disentangle the contribution of individual sources in the surrounding territory, and to identify main contributing sources. Sky brightness, naked eye stellar visibility and telescope limiting magnitude are produced as 3-dimensional arrays whose axes are the position on the sky and the atmospheric clarity. We compared our results to available measurements.
Derived equivalence of algebras
Institute of Scientific and Technical Information of China (English)
杜先能
1997-01-01
The derived equivalence and stable equivalence of algebras RmA and RmB are studied It is proved, using the tilting complex, that RmA and RmB are derived-equivalent whenever algebras A and B are derived-equivalent
Estimation of fossil-fuel CO2 emissions using satellite measurements of "proxy" species
Konovalov, Igor B.; Berezin, Evgeny V.; Ciais, Philippe; Broquet, Grégoire; Zhuravlev, Ruslan V.; Janssens-Maenhout, Greet
2016-11-01
Fossil-fuel (FF) burning releases carbon dioxide (CO2) together with many other chemical species, some of which, such as nitrogen dioxide (NO2) and carbon monoxide (CO), are routinely monitored from space. This study examines the feasibility of estimation of FF CO2 emissions from large industrial regions by using NO2 and CO column retrievals from satellite measurements in combination with simulations by a mesoscale chemistry transport model (CTM). To this end, an inverse modeling method is developed that allows estimating FF CO2 emissions from different sectors of the economy, as well as the total CO2 emissions, in a given region. The key steps of the method are (1) inferring "top-down" estimates of the regional budget of anthropogenic NOx and CO emissions from satellite measurements of proxy species (NO2 and CO in the case considered) without using formal a priori constraints on these budgets, (2) the application of emission factors (the NOx-to-CO2 and CO-to-CO2 emission ratios in each sector) that relate FF CO2 emissions to the proxy species emissions and are evaluated by using data of "bottom-up" emission inventories, and (3) cross-validation and optimal combination of the estimates of CO2 emission budgets derived from measurements of the different proxy species. Uncertainties in the top-down estimates of the NOx and CO emissions are evaluated and systematic differences between the measured and simulated data are taken into account by using original robust techniques validated with synthetic data. To examine the potential of the method, it was applied to the budget of emissions for a western European region including 12 countries by using NO2 and CO column amounts retrieved from, respectively, the OMI and IASI satellite measurements and simulated by the CHIMERE mesoscale CTM, along with the emission conversion factors based on the EDGAR v4.2 emission inventory. The analysis was focused on evaluation of the uncertainty levels for the top-down NOx and CO emission
DEFF Research Database (Denmark)
Gonzalez Eiras, Martin; Niepelt, Dirk
2015-01-01
Traditional "economic equivalence'' results, like the Ricardian equivalence proposition, define equivalence classes over exogenous policies. We derive "politico-economic equivalence" conditions that apply in environments where policy is endogenous and chosen sequentially. A policy regime...... and a state are equivalent to another such pair if both pairs give rise to the same allocation in politico-economic equilibrium. The equivalence conditions help to identify factors that render institutional change non-neutral and to construct politico-economic equilibria in new policy regimes. We exemplify...... their use in the context of several applications, relating to social security reform, tax-smoothing policies and measures to correct externalities....
High accuracy correction of blackbody radiation shift in an optical lattice clock
Middelmann, Thomas; Lisdat, Christian; Sterr, Uwe
2012-01-01
We have determined the frequency shift that blackbody radiation is inducing on the $5s^2$ $^1$S$_0$ -- $5s5p$ $^3$P$_0$ clock transition in strontium. Previously its uncertainty limited the uncertainty of strontium lattice clocks to $1\\times10^{-16}$. Now the uncertainty associated to the black body radiation shift correction translates to $5\\times 10^{-18}$ relative frequency uncertainty at room temperature. Our evaluation is based on a measurement of the differential dc-polarizability of the two clock states and on a modeling of the dynamic contribution using this value and experimental data for other atomic properties.
Upper limits to near-field radiative heat transfer: generalizing the blackbody concept
Miller, Owen D.; Rodriguez, Alejandro W.; Johnson, Steven G.
2016-09-01
For 75 years it has been known that radiative heat transfer can exceed far-field blackbody rates when two bodies are separated by less than a thermal wavelength. Yet an open question has remained: what is the maximum achievable radiative transfer rate? Here we describe basic energy-conservation principles that answer this question, yielding upper bounds that depend on the temperatures, material susceptibilities, and separation distance, but which encompass all geometries. The simple structures studied to date fall far short of the bounds, offering the possibility for significant future enhancement, with ramifications for experimental studies as well as thermophotovoltaic applications.
The Planck Blackbody Spectrum Follows from the Structure of Relativistic Spacetime
Boyer, Timothy H
2016-01-01
Here we show that within classical physics, the Planck blackbody spectrum can be derived directly from the structure of relativistic spacetime. In noninertial frames, thermal radiation at positive temperature is connected directly to zero-point radiation whose spectrum follows from the geodesic structure of the spacetime. The connection between zero-point radiation and thermal radiation at postive temperature is through a time-dilating conformal transformation in the noninertial frame. Transferring the spectrum back to Minskowski spacetime, the Planck spectrum is obtained.
Matsumoto, Takahiro; Tomita, Makoto
2010-06-21
Using a selective emitter with high emissivity in the visible wavelength region and low emissivity in the infrared wavelength region, we reduced the infrared contribution to the blackbody radiation spectrum and shifted the peak emission to shorter wavelengths. We made precise measurements of thermal radiation loss. The conversion efficiency from input electric power to visible light radiation was quantitatively evaluated with high accuracy. Using the proposed selective emitter, the conversion efficiencies in excess of 95% could be produced. Our conclusions pave the way for the design of incandescent lamps with luminous efficiencies exceeding 400 lm/W.
Bastiaansen, W.G.M.; Cheema, M.J.M.; Immerzeel, W.W.; Miltenburg, I.J.; Pelgrum, H.
2012-01-01
The surface energy fluxes and related evapotranspiration processes across the Indus Basin were estimated for the hydrological year 2007 using satellite measurements. The new ETLook remote sensing model (version 1) infers information on actual Evaporation (E) and actual Transpiration (T) from combine
Penning de Vries, M. J. M.; Tuinder, O. N. E.; Wagner, T.; Fromm, M.
2012-04-01
The Wallow wildfire of 2011 was one of the most devastating fires ever in Arizona, burning over 2,000 km2 in the states of Arizona and New Mexico. The fire originated in the Bear Wallow Wilderness area in June, 2011, and raged for more than a month. The intense heat of the fire caused the formation of a pyro-convective cloud. The resulting smoke plume, partially located above low-lying clouds, was detected by several satellite instruments, including GOME-2 on June 2. The UV Aerosol Index, indicative of aerosol absorption, reached a maximum of 12 on that day, pointing to an elevated plume with moderately absorbing aerosols. We have performed extensive model calculations assuming different aerosol optical properties to determine the total aerosol optical depth of the plume. The plume altitude, needed to constrain the aerosol optical depth, was obtained from independent satellite measurements. The model results were compared with UV Aerosol Index and UV reflectances measured by the GOME-2 polarization measurement devices, which have a spatial resolution of roughly 10x40 km2. Although neither the exact aerosol optical properties nor optical depth can be obtained with this method, the range in aerosol optical depth values that we calculate, combined with the assumed specific extinction mass factor of 5 m2/kg lead us to a rough estimate of the smoke plume mass that cannot, at present, be assessed in another way.
Computer-aided evaluation of the railway track geometry on the basis of satellite measurements
Specht, Cezary; Koc, Władysław; Chrostowski, Piotr
2016-05-01
In recent years, all over the world there has been a period of intensive development of GNSS (Global Navigation Satellite Systems) measurement techniques and their extension for the purpose of their applications in the field of surveying and navigation. Moreover, in many countries a rising trend in the development of rail transportation systems has been noticed. In this paper, a method of railway track geometry assessment based on mobile satellite measurements is presented. The paper shows the implementation effects of satellite surveying railway geometry. The investigation process described in the paper is divided on two phases. The first phase is the GNSS mobile surveying and the analysis obtained data. The second phase is the analysis of the track geometry using the flat coordinates from the surveying. The visualization of the measured route, separation and quality assessment of the uniform geometric elements (straight sections, arcs), identification of the track polygon (main directions and intersection angles) are discussed and illustrated by the calculation example within the article.
Fishman, J. J.; Creilson, J. K.; Parker, P. A.; Ainsworth, E. A.; Vining, G. G.; Szarka, J. L.
2009-05-01
High concentrations of ground-level ozone are frequently measured over farmland regions in many parts of the world. Since laboratory data show that ozone can significantly impact crop productivity if levels above a threshold concentration are reached, there is a consensus that crop yield should be impacted now and that the effects will become even more detrimental as global background concentrations continue to rise, as suggested by the latest IPCC report. Using the long-term record of tropospheric ozone derived from satellite measurements (http://asd-www.larc.nasa.gov/TOR/data.html), we present a methodology that can be used to assess the impact of regional ozone pollution on crop productivity. In this study, we use soybean crop yield data during a 5-year period over the Midwest of the United States and analyze the results using multiple linear regression statistical models. The results are consistent with findings using conventional ground-based measurements and with results obtained from an open-air experimental facility SoyFACE (Soybean Free Air Concentration Enrichment) in central Illinois. Our analysis suggests that the cost to the farmers globally is substantial, and supports other studies that calculate an economic loss to the farming community of more than 10 billion dollars annually.
Mizyuk, Artem; Senderov, Maxim; Korotaev, Gennady
2016-04-01
Large number of numerical ocean models were implemented for the Black Sea basin during last two decades. They reproduce rather similar structure of synoptical variability of the circulation. Since 00-s numerical studies of the mesoscale structure are carried out using high performance computing (HPC). With the growing capacity of computing resources it is now possible to reconstruct the Black Sea currents with spatial resolution of several hundreds meters. However, how realistic these results can be? In the proposed study an attempt is made to understand which spatial scales are reproduced by ocean model in the Black Sea. Simulations are made using parallel version of NEMO (Nucleus for European Modelling of the Ocean). A two regional configurations with spatial resolutions 5 km and 2.5 km are described. Comparison of the SST from simulations with two spatial resolutions shows rather qualitative difference of the spatial structures. Results of high resolution simulation are compared also with satellite observations and observation-based products from Copernicus using spatial correlation and spectral analysis. Spatial scales of correlations functions for simulated and observed SST are rather close and differs much from satellite SST reanalysis. Evolution of spectral density for modelled SST and reanalysis showed agreed time periods of small scales intensification. Using of the spectral analysis for satellite measurements is complicated due to gaps. The research leading to this results has received funding from Russian Science Foundation (project № 15-17-20020)
Li, Zhanqing; Leighton, H. G.; Cess, Robert D.
1993-01-01
A parameterization that relates the reflected solar flux at the top of the atmosphere to the net solar flux at the surface in terms of only the column water vapor amount and the solar zenith angle was tested against surface observations. Net surface fluxes deduced from coincidental collocated satellite-measured radiances and from measurements from towers in Boulder during summer and near Saskatoon in winter have mean differences of about 2 W/sq m, regardless of whether the sky is clear or cloudy. Furthermore, comparisons between the net fluxes deduced from the parameterization and from surface measurements showed equally good agreement when the data were partitioned into morning and afternoon observations. This is in contrast to results from an empirical clear-sky algorithm that is unable to account adequately for the effects of clouds and that shows, at Boulder, a distinct morning to afternoon variation. It is also demonstrated that the parameterization may be applied to irradiances at the top of the atmosphere that have been temporally averaged. The good agreement between the results of the parameterization and surface measurements suggests that the algorithm is a useful tool for a variety of climate studies.
Sheridan P. J.; Andrews, E.; Ogren, J A.; Tackett, J. L.; Winker, D. M.
2012-01-01
Between June 2006 and September 2009, an instrumented light aircraft measured over 400 vertical profiles of aerosol and trace gas properties over eastern and central Illinois. The primary objectives of this program were to (1) measure the in situ aerosol properties and determine their vertical and temporal variability and (2) relate these aircraft measurements to concurrent surface and satellite measurements. Underflights of the CALIPSO satellite show reasonable agreement in a majority of retrieved profiles between aircraft-measured extinction at 532 nm (adjusted to ambient relative humidity) and CALIPSO-retrieved extinction, and suggest that routine aircraft profiling programs can be used to better understand and validate satellite retrieval algorithms. CALIPSO tended to overestimate the aerosol extinction at this location in some boundary layer flight segments when scattered or broken clouds were present, which could be related to problems with CALIPSO cloud screening methods. The in situ aircraft-collected aerosol data suggest extinction thresholds for the likelihood of aerosol layers being detected by the CALIOP lidar. These statistical data offer guidance as to the likelihood of CALIPSO's ability to retrieve aerosol extinction at various locations around the globe.
Li, Zhanqing; Leighton, H. G.; Cess, Robert D.
1993-01-01
A parameterization that relates the reflected solar flux at the top of the atmosphere to the net solar flux at the surface in terms of only the column water vapor amount and the solar zenith angle was tested against surface observations. Net surface fluxes deduced from coincidental collocated satellite-measured radiances and from measurements from towers in Boulder during summer and near Saskatoon in winter have mean differences of about 2 W/sq m, regardless of whether the sky is clear or cloudy. Furthermore, comparisons between the net fluxes deduced from the parameterization and from surface measurements showed equally good agreement when the data were partitioned into morning and afternoon observations. This is in contrast to results from an empirical clear-sky algorithm that is unable to account adequately for the effects of clouds and that shows, at Boulder, a distinct morning to afternoon variation, which is presumably due to the predominance of different cloud types throughout the day. It is also demonstrated that the parameterization may be applied to irradiances at the top of the atmosphere that have been temporally averaged by using the temporally averaged column water vapor amount and the temporally averaged cosine of the solar zenith angle. The good agreement between the results of the parameterization and surface measurements suggests that the algorithm is a useful tool for a variety of climate studies.
Equivalence principles and electromagnetism
Ni, W.-T.
1977-01-01
The implications of the weak equivalence principles are investigated in detail for electromagnetic systems in a general framework. In particular, it is shown that the universality of free-fall trajectories (Galileo weak equivalence principle) does not imply the validity of the Einstein equivalence principle. However, the Galileo principle plus the universality of free-fall rotation states does imply the Einstein principle.
Institute of Scientific and Technical Information of China (English)
李良杰
2013-01-01
There are many researches about translation theories and methods in western translation history. Equivalence in transla⁃tion has always been the central issue for discussion. This paper gives a general review and comment on equivalence in translation in terms of three representative translation theorists and their views about equivalence in translation.
Energy Technology Data Exchange (ETDEWEB)
Janssen, R. M. J., E-mail: r.m.j.janssen@tudelft.nl [Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628CJ Delft (Netherlands); Endo, A. [Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628CJ Delft (Netherlands); Department of Microelectronics, Faculty of Electrical Engineering, Mathematics and Computer Science (EEMCS), Delft University of Technology, Mekelweg 4, 2628 CD Delft (Netherlands); Visser, P. J. de [Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628CJ Delft (Netherlands); SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584CA Utrecht (Netherlands); Klapwijk, T. M. [Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628CJ Delft (Netherlands); Physics Department, Moscow State Pedagogical University, Moscow 119991 (Russian Federation); Baselmans, J. J. A. [SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584CA Utrecht (Netherlands)
2014-11-10
We have measured and compared the response of hybrid NbTiN-Al Microwave Kinetic Inductance Detectors (MKIDs) to changes in bath temperature and illumination by sub-mm radiation. We show that these two stimulants have an equivalent effect on the resonance feature of hybrid MKIDs. We determine an electrical noise equivalent power (NEP) from the measured temperature responsivity, quasiparticle recombination time, superconducting transition temperature, and noise spectrum, all of which can be measured in a dark environment. For the two hybrid NbTiN-Al MKIDs studied in detail, the electrical NEP is within a factor of two of the optical NEP, which is measured directly using a blackbody source.
Puertas-Centeno, D.; Toranzo, I. V.; Dehesa, J. S.
2017-04-01
We introduce a biparametric Fisher-Rényi complexity measure for general probability distributions and we discuss its properties. This notion, which is composed of two entropy-like components (the Rényi entropy and the biparametric Fisher information), generalizes the basic Fisher-Shannon measure and the previous complexity quantifiers of Fisher-Rényi type. Then, we illustrate the usefulness of this notion by carrying out a information-theoretical analysis of the spectral energy density of a d-dimensional blackbody at temperature T. It is shown that the biparametric Fisher-Rényi measure of this quantum system has a universal character in the sense that it does not depend on temperature nor on any physical constant (e.g. Planck constant, speed of light, Boltzmann constant), but only on the space dimensionality d. Moreover, it decreases when d is increasing, but exhibits a non trivial behavior for a fixed d and a varying parameter, which somehow brings up a non standard structure of the blackbody d-dimensional density distribution.
Mixing of blackbodies: entropy production and dissipation of sound waves in the early Universe
Khatri, Rishi; Chluba, Jens
2012-01-01
Mixing of blackbodies with different temperatures creates a spectral distortion which, at lowest order, is a y-type distortion, indistinguishable from the thermal y-type distortion produced by the scattering of CMB photons by hot electrons residing in clusters of galaxies. This process occurs in the radiation-pressure dominated early Universe, when the primordial perturbations excite standing sound waves on entering the sound horizon. Photons from different phases of the sound waves, having different temperatures, diffuse through the electron-baryon plasma and mix together. This diffusion, with the length defined by Thomson scattering, dissipates sound waves and creates spectral distortions in the CMB. Of the total dissipated energy, 2/3 raises the average temperature of the blackbody part of spectrum, while 1/3 creates a distortion of y-type. It is well known that at redshifts 10^5< z< 2x10^6, comptonization rapidly transforms y-distortions into a Bose-Einstein spectrum. The chemical potential of the B...
An Equivalent Gauge and the Equivalence Theorem
Wulzer, Andrea
2014-01-01
I describe a novel covariant formulation of massive gauge theories in which the longitudinal polarization vectors do not grow with the energy. Therefore in the present formalism, differently from the ordinary one, the energy and coupling power-counting is completely transparent at the level of individual Feynman diagrams, with obvious advantages both at the conceptual and practical level. Since power-counting is transparent, the high-energy limit of the amplitudes involving longitudinal particles is immediately taken, and the Equivalence Theorem is easily demonstrated at all orders in perturbation theory. Since the formalism makes the Equivalence Theorem self-evident, and because it is based on a suitable choice of the gauge, we can call it an "Equivalent Gauge".
Directory of Open Access Journals (Sweden)
M. Schroedter-Homscheidt
2010-11-01
Full Text Available Modelling of aerosol particles with chemical transport models is still based mainly on static emission databases while episodic emissions cannot be treated sufficiently. To overcome this situation, a coupling of chemical mass concentration modelling with satellite-based measurements relying on physical and optical principles has been developed. This study deals with the observation operator for a component-wise assimilation of satellite measurements. It treats aerosol particles classified into water soluble, water insoluble, soot, sea salt and mineral dust containing aerosol particles in the atmospheric boundary layer as separately assimilated aerosol components. It builds on a mapping of aerosol classes used both in observation and model space taking their optical and chemical properties into account. Refractive indices for primary organic carbon particles, anthropogenic particles, and secondary organic species have been defined based on a literature review. Together with a treatment of different size distributions in observations and model state, this allows transforming the background from mass concentrations into aerosol optical depths. A two-dimensional, variational assimilation is applied for component-wise aerosol optical depths. Error covariance matrices are defined based on a validation against AERONET sun photometer measurements. Analysis fields are assessed threefold: (1 through validation against AERONET especially in Saharan dust outbreak situations, (2 through comparison with the British Black Smoke and Sulphur Dioxide Network for soot-containing particles, and (3 through comparison with measurements of the water soluble components SO_{4}, NH_{4}, and NO_{3} conducted by the EMEP (European Monitoring and Evaluation Programme network. Separately, for the water soluble, the soot and the mineral dust aerosol components a bias reduction and subsequent a root mean square error reduction is observed in the
Bowie Lecture: The Record of Sea Level Change from Satellite Measurements: What Have We Learned?
Nerem, R. S.
2005-12-01
Over the last decade, satellite geodetic measurements together with in situ measurements, have revolutionized our understanding of present-day sea level change. This is important because sea level change can be used as one barometer of climate variations and because of the implications sea level change has for coastal populations. With measurements from satellite altimeter missions (TOPEX/Posiedon and Jason), satellite gravity missions (GRACE), and the Global Positioning System (GPS), we are now able to start asking some important questions with regards to global sea level change and its regional variations. What has been the rate of global mean sea level change over the last dozen years? Is this rate different from the historical rate observed by the tide gauges over the last century? What are the principal causes of the observed sea level change, and are they related to anthropogenic climate variations? The record of sea level change from satellite altimetry will be reviewed, its error sources and limitations discussed, and the results placed in context with other estimates of sea level change from tide gauges, in situ measurements, and global climate models. The much shorter, but just as important, record of ocean mass variations from satellite gravity measurements will be similarly reviewed. In addition, GPS measurements of the deformation of the solid Earth due to the melting of continental ice and what they tell us about sea level change will be discussed. A sea level change budget will be presented, both for the altimetric era and the last century, containing estimates of contributions from thermal expansion, ocean mass changes (melting ice, runoff, etc.), and other contributions to sea level change. Finally, the need for continuing the satellite measurements of sea level change will be discussed in the context of future missions and the scientific gain that would result.
Improving knowledge of the surface salinity annual cycle with Aquarius satellite measurements
Lagerloef, G. S. E.
2016-12-01
To improve knowledge of the ocean surface salinity annual cycle, and its link to global precipitation patterns, remains a key science measurement objective for satellites. The Aquarius satellite data are applied here to address this, and the analysis is not as straightforward as it may seem. Sensor calibration is considered carefully to ensure that seasonality in external calibration data sources do not alias the satellite measurements. For example, quasi-monthly calibration error signals were identified early in the Aquarius mission. Subsequently, Aquarius data processing has relied primarily on an ocean target calibration method, whereby the satellite observations were co-located with output from the US Navy operational HYCOM model to adjust for these quasi-monthly calibration drifts. It was later determined that HYCOM salinity fields are themselves adjusted with a climatological restoring term, that imprints the seasonal climatology signal on the sensor calibration. When that output is compared with a parallel Aquarius data processing that bypasses the HYCOM ocean target calibration, and substitutes a simulation of the sensor electronics, the globally averaged output show very different annual signals between these trials. A modified ocean-target calibration, that employs satellite data matched directly with the in situ observations, is presently being investigated. The methodology uses signal processing to separate the satellite-in situ differences related to the sensor calibration from geophysical error sources. This remains a work-in-progress, and the results, with any unresolved issues, will be discussed. The presentation will also provide a very brief summary of Aquarius scientific accomplishments, the final "legacy" data set production, and the program to continue salinity data processing from other satellites.
Ichoku, Charles; Giglio, Louis; Wooster, Martin J.; Remer, Lorraine A.
2008-01-01
Remote sensing is the most practical means of measuring energy release from large open-air biomass burning. Satellite measurement of fire radiative energy (FRE) release rate or power (FRP) enables distinction between fires of different strengths. Based on a 1-km resolution fire data acquired globally by the MODerate-resolution Imaging Spectro-radiometer (MODIS) sensor aboard the Terra and Aqua satellites from 2000 to 2006, instanteaneous FRP values ranged between 0.02 MW and 1866 MW, with global daily means ranging between 20 and 40 MW. Regionally, at the Aqua-MODIS afternoon overpass, the mean FRP values for Alaska, Western US, Western Australia, Quebec and the rest of Canada are significantly higher than these global means, with Quebec having the overall highest value of 85 MW. Analysis of regional mean FRP per unit area of land (FRP flux) shows that a peak fire season in certain regions, fires can be responsible for up to 0.2 W/m(sup 2) at peak time of day. Zambia has the highest regional monthly mean FRP flux of approximately 0.045 W/m(sup 2) at peak time of day and season, while the Middle East has the lowest value of approximately 0.0005 W/m(sup 2). A simple scheme based on FRP has been devised to classify fires into five categories, to facilitate fire rating by strength, similar to earthquakes and hurricanes. The scheme uses MODIS measurements of FRP at 1-km resolution as follows: catagory 1 (less than 100 MW), category 2 (100 to less than 500 MW), category 3 (500 to less than 1000 MW), category 4 (1000 to less than 1500 MW), catagory 5 (greater than or equal to 1500 MW). In most regions of the world, over 90% of fires fall into category 1, while only less than 1% fall into each of categories 3 to 5, although these proportions may differ significantly from day to day and by season. The frequency of occurence of the larger fires is region specific, and could not be explained by ecosystem type alone. Time-series analysis of the propertions of higher category
A new blackbody radiation law based on fractional calculus and its application to NASA COBE data
Biyajima, Minoru; Mizoguchi, Takuya; Suzuki, Naomichi
2015-12-01
By applying fractional calculus to the equation proposed by M. Planck in 1900, we obtain a new blackbody radiation law described by a Mittag-Leffler (ML) function. We have analyzed NASA COBE data by means of a non-extensive formula with a parameter (q - 1) , a formula proposed by Ertik et al. with a fractional parameter (α - 1) , and our new formula including a parameter (p - 1) , as well as the Bose-Einstein distribution with a dimensionless chemical potential μ. It can be said that one role of the fractional parameter (p - 1) is almost the same as that of chemical potential (μ) as well as that of the parameter (q - 1) in the non-extensive approach.
Energy Technology Data Exchange (ETDEWEB)
Boyer, Timothy H [Department of Physics, City College of the City University of New York, New York, NY 10031 (United States)
2005-02-25
The blackbody radiation problem within classical physics is reviewed. It is again suggested that conformal symmetry is the crucial unrecognized aspect, and that only scattering by classical electromagnetic systems will provide equilibrium at the Planck spectrum. It is pointed out that the several calculations of radiation scattering using nonlinear mechanical systems do not preserve the Boltzmann distribution under adiabatic change of a parameter, and this fact seems at variance with our expectations in connection with derivations of Wien's displacement theorem. By contrast, the striking properties of charged particle motion in a Coulomb potential or in a uniform magnetic field suggest the possibility that these systems will fit with classical thermal radiation. It may be possible to give a full scattering calculation in the case of cyclotron motion in order to provide the needed test of the connection between conformal symmetry and classical thermal radiation.
A simple blackbody simulator with several possibilities and applications on thermography
dos Santos, Laerte; Lemos, Alisson Maria; Abi-Ramia, Marco Antônio
2016-05-01
Originally designed to make the practical examination on thermography certification1 possible, the device presented in this paper has demonstrated to be a very useful and versatile didactic tool for training centers and educational institutions, it can also be used as a low cost blackbody simulator to verify calibration of radiometers. It is a simple device with several functionalities for studying and for applications on heat transfer and radiometry, among them the interesting ability to thermally simulate the surface of real objects. On that functionality, if the device is seen by a thermographic camera, it reproduces the surface apparent temperatures of the object that it is simulating, at the same time, if it is seen by a naked eye it shows a visible image of that same surface. This functionality makes the practical study in the classroom possible, from different areas such as electrical, mechanical, medical, building, veterinary, etc.
Manche, E P
1978-06-01
A new instrumental technique for the determination of thermoluminescent glow curves, especially useful for investigation at high temperatures, is described. Two samples, identical in all respects except that one is preheated, are simultaneously heated. The light outputs from the samples are individually modulated at two different frequencies, fed to a single photomultiplier tube the output of which is amplified by two lock-in amplifiers. The selectively amplified signals are further fed to a differential amplifier which cancels out the undesirable blackbody radiation to give a signal due only to the luminophor. This technique conveniently extends the temperature range of thermoluminescence and further allows high-temperature investigation of emissions in the red region of the spectrum.
Fiedler, Lars; Newman, Stuart; Bakan, Stephan
2005-09-01
The nonlinearity of a mercury cadmium telluride photoconductive detector, an integral part of a modified commercial interferometer used for airborne research, has been analyzed and evaluated against a number of correction schemes. A high-quality blackbody with accurate temperature control has been used as a stable and well-characterized radiation source. The detector nonlinearity was established as a function of scene temperature between 194 and 263 K. Second- and third-order corrections to the measured interferogram have been tested by analyzing the measured signal both within and outside the spectral response region of the detector. A combined correction scheme is proposed that best represents the real nonlinear response of the detector.
Isotropic blackbody cosmic microwave background radiation as evidence for a homogeneous universe.
Clifton, Timothy; Clarkson, Chris; Bull, Philip
2012-08-03
The question of whether the Universe is spatially homogeneous and isotropic on the largest scales is of fundamental importance to cosmology but has not yet been answered decisively. Surprisingly, neither an isotropic primary cosmic microwave background (CMB) nor combined observations of luminosity distances and galaxy number counts are sufficient to establish such a result. The inclusion of the Sunyaev-Zel'dovich effect in CMB observations, however, dramatically improves this situation. We show that even a solitary observer who sees an isotropic blackbody CMB can conclude that the Universe is homogeneous and isotropic in their causal past when the Sunyaev-Zel'dovich effect is present. Critically, however, the CMB must either be viewed for an extended period of time, or CMB photons that have scattered more than once must be detected. This result provides a theoretical underpinning for testing the cosmological principle with observations of the CMB alone.
Design and Calibration of a Cryogenic Blackbody Calibrator at Centimeter Wavelengths
Kogut, A J; Fixsen, D J; Limon, M; Mirel, P G A; Levin, S; Seiffert, M; Lubin, P M
2004-01-01
We describe the design and calibration of an external cryogenic blackbody calibrator used for the first two flights of the Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission (ARCADE) instrument. The calibrator consists of a microwave absorber weakly coupled to a superfluid liquid helium bath. Half-wave corrugations viewed 30 deg off axis reduce the return loss below -35 dB. Ruthenium oxide resistive thermometers embedded within the absorber monitor the temperature across the face of the calibrator. The thermal calibration transfers the calibration of a reference thermometer to the flight thermometers using the flight thermometer readout system. Data taken near the superfluid transition in 8 independent calibrations 4 years apart agree within 0.3 mK, providing an independent verification of the thermometer calibration at temperatures near that of the cosmic microwave background.
An atomic clock with $1\\times 10^{-18}$ room-temperature blackbody Stark uncertainty
Beloy, K; Phillips, N B; Sherman, J A; Schioppo, M; Lehman, J; Feldman, A; Hanssen, L M; Oates, C W; Ludlow, A D
2014-01-01
The Stark shift due to blackbody radiation (BBR) is the key factor limiting the performance of many atomic frequency standards, with the BBR environment inside the clock apparatus being difficult to characterize at a high level of precision. Here we demonstrate an in-vacuum radiation shield that furnishes a uniform, well-characterized BBR environment for the atoms in an ytterbium optical lattice clock. Operated at room temperature, this shield enables specification of the BBR environment to a corresponding fractional clock uncertainty contribution of $5.5 \\times 10^{-19}$. Combined with uncertainty in the atomic response, the total uncertainty of the BBR Stark shift is now $1\\times10^{-18}$. Further operation of the shield at elevated temperatures enables a direct measure of the BBR shift temperature dependence and demonstrates consistency between our evaluated BBR environment and the expected atomic response.
Institute of Scientific and Technical Information of China (English)
石雏凤
2009-01-01
Nida's translation theories, especially for his "Dynamic equivalence theory", are highly praised and adopted in Chinese translation circle. Howev-er, there are a lot of criticism and misunderstanding at the same time. This paper explores the issue on translation equivalence so as to benefit our translation studies on both theory and practice level.
Sister, Ilya; Leviatan, Yehuda; Schächter, Levi
2017-06-12
Planck's famous blackbody radiation law was derived under the assumption that the dimensions of the radiating body are significantly larger than the radiated wavelengths. What is unique about Planck's formula is the fact that it is independent of the exact loss mechanism and the geometry. Therefore, for a long period of time, it was regarded as a fundamental property of all materials. Deviations from its predictions were attributed to imperfections and referred to as the emissivity of the specific body, a quantity which was always assumed to be smaller than unity. Recent studies showed that the emission spectrum is affected by the geometry of the body and in fact, in a limited frequency range, the emitted spectrum may exceed Planck's prediction provided the typical size of the body is of the same order of magnitude as the emitted wavelength. For the investigation of the blackbody radiation from an arbitrarily shaped body, we developed a code which incorporates the fluctuation-dissipation theorem (FDT) and the source model technique (SMT). The former determines the correlation between the quasi-microscopic current densities in the body and the latter is used to solve the electromagnetic problem numerically. In this study we present the essence of combining the two concepts. We verify the validity of our code by comparing its results obtained for the case of a sphere against analytic results and discuss how the accuracy of the solution is assessed in the general case. Finally, we illustrate several configurations in which the emitted spectrum exceeds Planck's prediction as well as cases in which the geometrical resonances of the body are revealed.
Ostilli, Massimo; Presilla, Carlo
2017-06-01
We study the thermalization of an ensemble of N elementary, arbitrarily complex, quantum systems, mutually noninteracting but coupled as electric or magnetic dipoles to a blackbody radiation. The elementary systems can be all the same or belong to different species, distinguishable or indistinguishable, located at fixed positions or having translational degrees of freedom. Even if the energy spectra of the constituent systems are nondegenerate, as we suppose, the ensemble unavoidably presents degeneracies of the energy levels and/or of the energy gaps. We show that, due to these degeneracies, a thermalization analysis performed by the popular quantum optical master equation reveals a number of serious pathologies, possibly including a lack of ergodicity. On the other hand, a consistent thermalization scenario is obtained by introducing a Lindblad-based approach, in which the Lindblad operators, instead of being derived from a microscopic calculation, are established as the elements of an operatorial basis with squared amplitudes fixed by imposing a detailed balance condition and requiring their correspondence with the dipole transition rates evaluated under the first-order perturbation theory. Due to the above-mentioned degeneracies, this procedure suffers a basis arbitrariness, which, however, can be removed by exploiting the fact that the thermalization of an ensemble of noninteracting systems cannot depend on the ensemble size. As a result, we provide a clear-cut partitioning of the thermalization time into dissipation and decoherence times, for which we derive formulas giving the dependence on the energy levels of the elementary systems, the size N of the ensemble, and the temperature of the blackbody radiation.
Equivalence principles exotica
Institute of Scientific and Technical Information of China (English)
C.S. UNNIKRISHNAN; George T. GILLIES
2008-01-01
This is a short review of the different prin-ciples of equivalence stated and used in the context of the gravitational interaction. We emphasize the need for precision in stating and differentiating these different equivalence principles, especially in the context of preva-lent confusion regarding the applicability of the weak equivalence principle in quantum mechanics. We discuss several empirical results pertaining to the validity of the equivalence principle in exotic physical sitautions not di-rectly amenable to experimental tests. We conclude with a section on the physical basis of the universal validity of the equivalence principle, as manifest in the universality of free fall, and discuss its link to cosmic gravity.
Morozova, S. P.; Dunaev, A. Y.; Katysheva, A. A.; Sapritsky, V. I.; Parfentyev, N. A.; Ogarev, S. A.; Karpunin, D. N.
2017-05-01
The new stage of the development of space-borne information systems is the creation of the Global Earth Observation System. For the full functioning of such a system, it is necessary to provide the uniformity of measurements of all national systems as members of the global system, with high-quality measurement data. This requires the implementation of a high level of ground (prelaunch) calibration of Earth remote sensing instruments. To solve these problems, there were created calibration facilities on the basis of large vacuum chambers with vacuum reference radiation sources, including sources on the basis of black bodies with a wide aperture of 500 mm in the spectral range from 3 {μ}m to 14 {μ}m. Such a facility was created by FGUP "VNIIOFI" in cooperation with FGUP "TsNIIMash". The ground calibration of Earth remote sensing instruments is being carried out by using blackbody models as radiation sources with known spectral radiance. Facility for ground calibration of remote sensing devices on spectral radiance is based on the usage of a large-aperture blackbody (LABB) with 500 mm diameter and working temperature range from 213 K to 423 K, as a radiation source. This calibration setup comprises a set of reference blackbodies, such as a blackbody on the phase transition of Gallium, a variable-temperature blackbody with temperature range from 213 K to 423 K, a reference blackbody cooled with liquid nitrogen, and IR Fourier spectrometer utilized as a comparator to perform LABB calibration on spectral radiance. The second important characteristic of LABB is the uniformity of spectral radiance across the radiating aperture of this blackbody. The paper describes the device for measuring the spatial homogeneity of the radiation power of the LABB's radiating surface. This device is based on the use of two-color InSb-CdHgTe detector equipped with modulator and IR lens, which are mounted on a two-axis translation stage suitable for operation in vacuum and installed in the
Water heat pipe blackbody as a reference spectral radiance source between 50°C and 250°C
Noorma, M.; Mekhontsev, S.; Khromchenko, V.; Litorja, M.; Cagran, C.; Zeng, J.; Hanssen, L.
2006-04-01
Realization of a radiometric temperature scale for near ambient temperatures with accuracy at the 20 to 50 mK level is crucial for a number of demanding military and commercial applications. In support of such measurements, radiation sources with high stability and spatial uniformity must be developed as reference and working standards. Traditionally, the temperature scale, maintained at the National Institute of Standards and Technology (NIST), relies on water bath and oil bath blackbodies in this temperature range. Recently, a water heat pipe blackbody was used at NIST as a spectral radiance source in a spectral emissivity measurement facility. Now a new, more versatile high emissivity water heat pipe blackbody was designed and characterized to be used as a reference radiance source for the radiometric temperature scale realization between 50 °C and 250 °C. Furthermore, it will serve as a reference source for the infrared spectral radiance measurements between 2.5 μm and 20 μm. The calculated spectral emissivity of the painted copper alloy cavity was verified by reflectance measurements using a CO II laser at 10.6 μm wavelength. The spatial thermal uniformity and stability of the blackbody were characterized. Two independent realizations of the radiometric temperature scale were compared in order to verify the accuracy of the scale. Radiance temperature, calculated from the cavity temperature measured with a calibrated PRT contact thermometer and from the emissivity of the cavity, was compared to the radiance temperature, directly measured with a reference pyrometer, which was calibrated with a set of fixed point blackbodies. The difference was found to be within measurement uncertainties.
Kechris, Alexander S
2004-01-01
This volume provides a self-contained introduction to some topics in orbit equivalence theory, a branch of ergodic theory. The first two chapters focus on hyperfiniteness and amenability. Included here are proofs of Dye's theorem that probability measure-preserving, ergodic actions of the integers are orbit equivalent and of the theorem of Connes-Feldman-Weiss identifying amenability and hyperfiniteness for non-singular equivalence relations. The presentation here is often influenced by descriptive set theory, and Borel and generic analogs of various results are discussed. The final chapter is a detailed account of Gaboriau's recent results on the theory of costs for equivalence relations and groups and its applications to proving rigidity theorems for actions of free groups.
Measurement of the energy and power radiated by a pulsed blackbody x-ray source
Directory of Open Access Journals (Sweden)
H. C. Ives
2006-11-01
Full Text Available We have developed a diagnostic system that measures the spectrally integrated (i.e. the total energy and power radiated by a pulsed blackbody x-ray source. The total-energy-and-power (TEP diagnostic system is optimized for blackbody temperatures between 50 and 350 eV. The system can view apertured sources that radiate energies and powers as high as 2 MJ and 200 TW, respectively, and has been successfully tested at 0.84 MJ and 73 TW on the Z pulsed-power accelerator. The TEP system consists of two pinhole arrays, two silicon-diode detectors, and two thin-film nickel bolometers. Each of the two pinhole arrays is paired with a single silicon diode. Each array consists of a 38×38 square array of 10-μm-diameter pinholes in a 50-μm-thick tantalum plate. The arrays achromatically attenuate the x-ray flux by a factor of ∼1800. The use of such arrays for the attenuation of soft x rays was first proposed by Turner and co-workers [Rev. Sci. Instrum. 70, 656 (1999RSINAK0034-674810.1063/1.1149385]. The attenuated flux from each array illuminates its associated diode; the diode’s output current is recorded by a data-acquisition system with 0.6-ns time resolution. The arrays and diodes are located 19 and 24 m from the source, respectively. Because the diodes are designed to have an approximately flat spectral sensitivity, the output current from each diode is proportional to the x-ray power. The nickel bolometers are fielded at a slightly different angle from the array-diode combinations, and view (without pinhole attenuation the same x-ray source. The bolometers measure the total x-ray energy radiated by the source and—on every shot—provide an in situ calibration of the array-diode combinations. Two array-diode pairs and two bolometers are fielded to reduce random uncertainties. An analytic model (which accounts for pinhole-diffraction effects of the sensitivity of an array-diode combination is presented.
Directory of Open Access Journals (Sweden)
P. J. Sheridan
2012-12-01
Full Text Available Between June 2006 and September 2009, an instrumented light aircraft measured over 400 vertical profiles of aerosol and trace gas properties over eastern and central Illinois. The primary objectives of this program were to (1 measure the in situ aerosol properties and determine their vertical and temporal variability and (2 relate these aircraft measurements to concurrent surface and satellite measurements. The primary profile location was within 15 km of the NOAA/ESRL surface aerosol monitoring station near Bondville, Illinois. Identical instruments at the surface and on the aircraft ensured that the data from both platforms would be directly comparable and permitted a determination of how representative surface aerosol properties were of the lower column. Aircraft profiles were also conducted occasionally at two other nearby locations to increase the frequency of A-Train satellite underflights for the purpose of comparing in situ and satellite-retrieved aerosol data. Measurements of aerosol properties conducted at low relative humidity over the Bondville site compare well with the analogous surface aerosol data and do not indicate any major sampling issues or that the aerosol is radically different at the surface compared with the lowest flyby altitude of ~ 240 m above ground level. Statistical analyses of the in situ vertical profile data indicate that aerosol light scattering and absorption (related to aerosol amount decreases substantially with increasing altitude. Parameters related to the nature of the aerosol (e.g., single-scattering albedo, Ångström exponent, etc., however, are relatively constant throughout the mixed layer, and do not vary as much as the aerosol amount throughout the profile. While individual profiles often showed more variability, the median in situ single-scattering albedo was 0.93–0.95 for all sampled altitudes. Several parameters (e.g., submicrometer scattering fraction, hemispheric backscattering fraction, and
Sensitivity of blackbody effective emissivity to wavelength and temperature: By genetic algorithm
Ejigu, E. K.; Liedberg, H. G.
2013-09-01
A variable-temperature blackbody (VTBB) is used to calibrate an infrared radiation thermometer (pyrometer). The effective emissivity (ɛeff) of a VTBB is dependent on temperature and wavelength other than the geometry of the VTBB. In the calibration process the effective emissivity is often assumed to be constant within the wavelength and temperature range. There are practical situations where the sensitivity of the effective emissivity needs to be known and correction has to be applied. We present a method using a genetic algorithm to investigate the sensitivity of the effective emissivity to wavelength and temperature variation. Two matlab® programs are generated: the first to model the radiance temperature calculation and the second to connect the model to the genetic algorithm optimization toolbox. The effective emissivity parameter is taken as a chromosome and optimized at each wavelength and temperature point. The difference between the contact temperature (reading from a platinum resistance thermometer or liquid in glass thermometer) and radiance temperature (calculated from the ɛeff values) is used as an objective function where merit values are calculated and best fit ɛeff values selected. The best fit ɛeff values obtained as a solution show how sensitive they are to temperature and wavelength parameter variation. Uncertainty components that arise from wavelength and temperature variation are determined based on the sensitivity analysis. Numerical examples are considered for illustration.
De Lucas, Javier
2015-03-01
A simple geometrical model for calculating the effective emissivity in blackbody cylindrical cavities has been developed. The back ray tracing technique and the Monte Carlo method have been employed, making use of a suitable set of coordinates and auxiliary planes. In these planes, the trajectories of individual photons in the successive reflections between the cavity points are followed in detail. The theoretical model is implemented by using simple numerical tools, programmed in Microsoft Visual Basic for Application and Excel. The algorithm is applied to isothermal and non-isothermal diffuse cylindrical cavities with a lid; however, the basic geometrical structure can be generalized to a cylindro-conical shape and specular reflection. Additionally, the numerical algorithm and the program source code can be used, with minor changes, for determining the distribution of the cavity points, where photon absorption takes place. This distribution could be applied to the study of the influence of thermal gradients on the effective emissivity profiles, for example. Validation is performed by analyzing the convergence of the Monte Carlo method as a function of the number of trials and by comparison with published results of different authors.
de Martino, I; Atrio-Barandela, F; Ebeling, H; Kashlinsky, A; Kocevski, D; Martins, C J A P
2015-01-01
We constrain the deviation of adiabatic evolution of the Universe using the data on the Cosmic Microwave Background (CMB) temperature anisotropies measured by the {\\it Planck} satellite and a sample of 481 X-ray selected clusters with spectroscopically measured redshifts. To avoid antenna beam effects, we bring all the maps to the same resolution. We use a CMB template to subtract the cosmological signal while preserving the Thermal Sunyaev-Zeldovich (TSZ) anisotropies; next, we remove galactic foreground emissions around each cluster and we mask out all known point sources. If the CMB black-body temperature scales with redshift as $T(z)=T_0(1+z)^{1-\\alpha}$, we constrain deviations of adiabatic evolution to be $\\alpha=-0.007\\pm 0.013$, consistent with the temperature-redshift relation of the standard cosmological model. This result could suffer from a potential bias associated with the CMB template, that we quantify it to be less than $-0.02$, but is free from those biases associated with using TSZ selected ...
Uncertainty calculation of the effective emissivity of cylinder-conical blackbody cavities
De Lucas, Javier; Juan Segovia, José
2016-02-01
A numerical and geometrical model for calculating the local effective emissivity of isothermal blackbody cylinder-conical cavities with lid, assuming diffuse reflection, is described. This has been developed by generalizing previous models based on conical and cylindrical geometries. The model has been validated by determining the diffusely reflected photon trajectories and the corresponding experimental view factors between given pairs of surface elements. Differences compared to theoretical values, were subsequently analyzed in terms of the model’s intrinsic uncertainty. A well-defined numerical function that calculates the effective emissivity as a function of its natural variables, intrinsic emissivity and geometrical parameters, is established. In order to calculate the probability distribution of the output quantity, we use the Monte Carlo method for the propagation of the probability distributions that characterize our knowledge concerning the values of the influence variables. The model is applied to heat-pipe black bodies installed at our laboratory, previously characterized at the PTB. A comparison with published uncertainty results, obtained by applying classical uncertainty propagation techniques, is also made.
Current Conveyor Equivalent Circuits
Directory of Open Access Journals (Sweden)
Tejmal S. Rathore
2012-02-01
Full Text Available An equivalence between a class of (current conveyor CC II+ and CC II- circuits is established. CC IIequivalent circuit uses one extra element. However, under certain condition, the extra element can be eliminated. As an illustration of the application of this equivalence, minimal first and second order all-pass filters are derived. Incertain cases, it is possible to compensate the effect of the input resistor of CC at port X. At the end, an open problem of realizing an Nth order (N > 2 minimal all-pass filter is stated.
Mika, Monika; Kudach, Jakub
2014-06-01
The publication has a cognitive research character. It presents a comparative analysis of free Internet services in Poland and abroad, used to adjust the data obtained using satellite measurement techniques. The main aim of this work is to describe and compare free tools for satellite data processing and to examine them for possible use in the surveying works in Poland. Among the many European and global services three of them dedicated to satellite measurements were selected: ASG-EUPOS (Poland), APPS (USA) and CSRS (Canada). The publication contains the results of calculations using these systems. Calculations were based on RINEX files obtained via postprocessing service (ASG-EUPOS network) POZGEO D for 12 reference stations in the South Poland. In order to examine differences in results between the ASG-EUPOS, APPS and CSRS the transformation points coordinate to a single coordinate system ETRF 2000 (in force in Poland) was made. Studies have shown the possibility of the calculation in Poland (in postprocessing mode) using the analyzed applications with global coverage.
van der Wijk, V.; Bai, Shaoping; Ceccarelli, Marco
2015-01-01
In this paper it is shown how a general 2-DoF dyad can be designed mass equivalent to a general (1-DoF) link element. This is useful in the synthesis of balanced mechanisms, for instance to increase or reduce the number of DoFs of a balanced mechanism maintaining its balance. Also it can be used as
van der Wijk, V.
2015-01-01
In this paper it is shown how a general 3-DoF triad can be designed mass equivalent to a general (1-DoF) link element. This is useful in the synthesis of shaking force balanced and statically balanced mechanisms, for instance to add or remove a number of DoFs of a balanced mechanism maintaining its
Equivalence of Differential System
Institute of Scientific and Technical Information of China (English)
Zheng-xin Zhou
2004-01-01
Using refiecting function of Mironenko we construct some differential systems which are equivalent to the given differential system.This gives us an opportunity to find out the monodromic matrix of these periodi csystems which are not integrable in finite terms.
Konovalov, Igor B.; Beekmann, Matthias; Berezin, Evgeny V.; Formenti, Paola; Andreae, Meinrat O.
2017-04-01
Carbonaceous aerosol released into the atmosphere from open biomass burning (BB) is known to undergo considerable chemical and physical transformations (aging). However, there is substantial controversy about the nature and observable effects of these transformations. A shortage of consistent observational evidence on BB aerosol aging processes under different environmental conditions and at various temporal scales hinders development of their adequate representations in chemistry transport models (CTMs). In this study, we obtain insights into the BB aerosol dynamics by using available satellite measurements of aerosol optical depth (AOD) and carbon monoxide (CO). The basic concept of our method is to consider AOD as a function of the BB aerosol photochemical age (that is, the time period characterizing the exposure of BB aerosol emissions to atmospheric oxidation reactions) predicted by means of model tracers. We evaluate the AOD enhancement ratio (ER) defined as the ratio of optical depth of actual BB aerosol with respect to that of a modeled aerosol tracer that is assumed to originate from the same fires as the real BB aerosol but that is not affected by any aging processes. To limit possible effects of model transport errors, the AOD measurements are normalized to CO column amounts that are also retrieved from satellite measurements. The method is applied to the analysis of the meso- and synoptic-scale evolution of aerosol in smoke plumes from major wildfires that occurred in Siberia in summer 2012. AOD and CO retrievals from MODIS and IASI measurements, respectively, are used in combination with simulations performed with the CHIMERE CTM. The analysis indicates that aging processes strongly affected the evolution of BB aerosol in the situation considered, especially in dense plumes (with spatial average PM2. 5 concentration exceeding 100 µg m-3). For such plumes, the ER is found to increase almost 2-fold on the scale of ˜ 10 h of daytime aerosol evolution
From equivalence to adaptation
Directory of Open Access Journals (Sweden)
Paulina Borowczyk
2009-01-01
Full Text Available The aim of this paper is to illustrate in which cases the translators use the adaptation when they are confronted with a term related to sociocultural aspects. We will discuss the notions of equivalence and adaptation and their limits in the translation. Some samples from Arte TV news and from the American film Shrek translated into Polish, German and French will be provided as a support for this article.
Equivalence Relations of -Algebra Extensions
Indian Academy of Sciences (India)
Changguo Wei
2010-04-01
In this paper, we consider equivalence relations of *-algebra extensions and describe the relationship between the isomorphism equivalence and the unitary equivalence. We also show that a certain group homomorphism is the obstruction for these equivalence relations to be the same.
Energy Technology Data Exchange (ETDEWEB)
Cooper, P.W.
1994-07-01
The term ``TNT Equivalence`` is used throughout the explosives and related industries to compare the effects of the output of a given explosive to that of TNT. This is done for technical design reasons in scaling calculation such as for the prediction of blast waves, craters, and structural response, and is also used as a basis for government regulations controlling the shipping, handling and storage of explosive materials, as well as for the siting and design of explosive facilities. TNT equivalence is determined experimentally by several different types of tests, the most common of which include: plate dent, ballistic mortar, trauzl, sand crush, and air blast. All of these tests do not necessarily measure the same output property of the sample explosive. As examples of this, some tests depend simply upon the CJ pressure, some depend upon the PV work in the CJ zone and in the Taylor wave behind the CJ plane, some are functions of the total work which includes that from secondary combustion in the air mixing region of the fireball and are acutely effected by the shape of the pressure-time profile of the wave. Some of the tests incorporate systematic errors which are not readily apparent, and which have a profound effect upon skewing the resultant data. Further, some of the tests produce different TNT Equivalents for the same explosive which are a function of the conditions at which the test is run. This paper describes the various tests used, discusses the results of each test and makes detailed commentary on what the test is actually measuring, how the results may be interpreted, and if and how these results can be predicted by first principals based calculations. Extensive data bases are referred to throughout the paper and used in examples for each point in the commentaries.
Indian Academy of Sciences (India)
B K Sahoo
2014-08-01
We present here an overview of the role of the multipolar black-body radiation (BBR) shifts in the single ion atomic clocks to appraise the anticipated 10-18 uncertainty level. With an attempt to use the advanced technologies for reducing the instrumental uncertainties at the unprecedented low, it is essential to investigate contributions from the higher-order systematics to achieve the ambitious goal of securing the most precise clock frequency standard. In this context, we have analysed contributions to the BBR shifts from the multipolar polarizabilities in a few ion clocks.
Establishing Substantial Equivalence: Proteomics
Lovegrove, Alison; Salt, Louise; Shewry, Peter R.
Wheat is a major crop in world agriculture and is consumed after processing into a range of food products. It is therefore of great importance to determine the consequences (intended and unintended) of transgenesis in wheat and whether genetically modified lines are substantially equivalent to those produced by conventional plant breeding. Proteomic analysis is one of several approaches which can be used to address these questions. Two-dimensional PAGE (2D PAGE) remains the most widely available method for proteomic analysis, but is notoriously difficult to reproduce between laboratories. We therefore describe methods which have been developed as standard operating procedures in our laboratory to ensure the reproducibility of proteomic analyses of wheat using 2D PAGE analysis of grain proteins.
Stuttering Equivalence for Parity Games
Cranen, Sjoerd; Willemse, Tim A C
2011-01-01
We study the process theoretic notion of stuttering equivalence in the setting of parity games. We demonstrate that stuttering equivalent vertices have the same winner in the parity game. This means that solving a parity game can be accelerated by minimising the game graph with respect to stuttering equivalence. While, at the outset, it might not be clear that this strategy should pay off, our experiments using typical verification problems illustrate that stuttering equivalence speeds up solving parity games in many cases.
Directory of Open Access Journals (Sweden)
M. Beekmann
2013-01-01
Full Text Available Multi-annual satellite measurements of tropospheric NO2 columns are used for evaluation of CO2 emission changes in China in the period from 1996 to 2008. Indirect annual top-down estimates of CO2 emissions are derived from the satellite NO2 columns measurements by means of a simple inverse modeling procedure involving simulations performed with the CHIMERE mesoscale chemistry transport model and the CO2 to NOx emission ratios from the Emission Database for Global Atmospheric Research version 4.2 (EDGAR v4.2 global anthropogenic emission inventory. Exponential trends in the normalized time series of annual emission are evaluated separately for the periods from 1996 to 2001 and from 2001 to 2008. The results indicate that the both periods manifest strong positive trends in the CO2 emissions, and that the trend in the second period was significantly larger than the trend in the first period. Specifically, the trends in the first and second periods are estimated to be in the range from 3.7 to 8.0 and from 9.5 to 13.0 percent per year, respectively, taking into account both statistical and probable systematic uncertainties. Comparison of our top-down estimates of the CO2 emission changes with the corresponding bottom-up estimates provided by EDGAR v4.2 and Global Carbon Project (GCP emission inventories reveals that while acceleration of the CO2 emission growth in the considered period is a common feature of the both kinds of estimates, nonlinearity in the CO2 emission changes may be strongly exaggerated in the emission inventories. Specifically, the atmospheric NO2 observations do not confirm the existence of a sharp bend in the emission inventory data time series in the period from 2000 to 2002. A significant quantitative difference is revealed between the bottom-up and top-down estimates of the CO2 emission trend in the period from 1996 to 2001 (specifically, the trend was not positive according to the emission inventories, but is strongly
Basak, Rupal
2014-01-01
GRB~090618 is a bright GRB with multiple pulses. It shows evidence of a thermal emission in the initial pulses as well as in the early afterglow phase. We investigate the shape and evolution of the thermal component in the early afterglow/ late prompt emission phase using data from Swift/BAT, Swift/XRT, and Fermi/GBM detectors. An independent fit to the BAT and the XRT data reveals two correlated blackbodies with monotonically decreasing temperatures. Hence we investigated the combined data with a model consisting of two blackbodies and a power-law (2BBPL), a model suggested for several bright GRBs. We elicit the following interesting features of the 2BBPL model: a) the same model is applicable from the peak of the last pulse in the prompt emission to the afterglow emission, b) the ratio of temperatures and the fluxes of the two black bodies remain constant throughout the observations, c) the black body temperatures and fluxes show a monotonic decrease with time, with the fluxes dropping about a factor of two...
Directory of Open Access Journals (Sweden)
O. J. Marsh
2013-09-01
Full Text Available Ocean tides close to the grounding line of outlet glaciers around Antarctica have been shown to directly influence ice velocity, both linearly and non-linearly. These fluctuations can be significant and have the potential to affect satellite measurements of ice discharge, which assume displacement between satellite passes to be consistent and representative of annual means. Satellite observations of horizontal velocity variation in the grounding zone are also contaminated by vertical tidal effects, the importance of which is highlighted here in speckle tracking measurements. Eight TerraSAR-X scenes from the grounding zone of the Beardmore Glacier are analysed in conjunction with GPS measurements to determine short-term and decadal trends in ice velocity. Diurnal tides produce horizontal velocity fluctuations of >50% on the ice shelf, recorded in the GPS data 4 km downstream of the grounding line. This variability decreases rapidly to <5% only 15 km upstream of the grounding line. Daily fluctuations are smoothed to <1% in the 11-day repeat pass TerraSAR-X imagery, but fortnightly variations over this period are still visible and show that satellite-velocity measurements can be affected by tides over longer periods. The measured tidal displacement observed in radar look direction over floating ice also allows the grounding line to be identified, using differential speckle tracking where phase information cannot be easily unwrapped.
Why scalar-tensor equivalent theories are not physically equivalent?
Sk., Nayem
2016-01-01
Whether Jordan's and Einstein's frame descriptions of F(R) theory of gravity are physically equivalent, is a long standing debate. However, none questioned on true mathematical equivalence, since classical field equations may be translated from one frame to the other following a transformation relation. Nevertheless, true mathematical equivalence is only established, if all the mathematical results derived from one frame may be translated to the other. Here we show that, neither Noether equations, nor quantum equations may be translated from one frame to the other. The reason being the momenta can't be translated. This appears to be the cause for dynamical in-equivalence.
Directory of Open Access Journals (Sweden)
D. Molden
2012-11-01
Full Text Available Coping with the issue of water scarcity and growing competition for water among different sectors requires proper water management strategies and decision processes. A pre-requisite is a clear understanding of the basin hydrological processes, manageable and unmanageable water flows, the interaction with land use and opportunities to mitigate the negative effects and increase the benefits of water depletion on society. Currently, water professionals do not have a common framework that links hydrological flows to user groups of water and their benefits. The absence of a standard hydrological and water management summary is causing confusion and wrong decisions. The non-availability of water flow data is one of the underpinning reasons for not having operational water accounting systems for river basins in place. In this paper we introduce Water Accounting Plus (WA+, which is a new framework designed to provide explicit spatial information on water depletion and net withdrawal processes in complex river basins. The influence of land use on the water cycle is described explicitly by defining land use groups with common characteristics. Analogous to financial accounting, WA+ presents four sheets including (i a resource base sheet, (ii a consumption sheet, (iii a productivity sheet, and (iv a withdrawal sheet. Every sheet encompasses a set of indicators that summarize the overall water resources situation. The impact of external (e.g. climate change and internal influences (e.g. infrastructure building can be estimated by studying the changes in these WA+ indicators. Satellite measurements can be used for 3 out of the 4 sheets, but is not a precondition for implementing WA+ framework. Data from hydrological models and water allocation models can also be used as inputs to WA+.
Directory of Open Access Journals (Sweden)
P. Karimi
2013-07-01
Full Text Available Coping with water scarcity and growing competition for water among different sectors requires proper water management strategies and decision processes. A pre-requisite is a clear understanding of the basin hydrological processes, manageable and unmanageable water flows, the interaction with land use and opportunities to mitigate the negative effects and increase the benefits of water depletion on society. Currently, water professionals do not have a common framework that links depletion to user groups of water and their benefits. The absence of a standard hydrological and water management summary is causing confusion and wrong decisions. The non-availability of water flow data is one of the underpinning reasons for not having operational water accounting systems for river basins in place. In this paper, we introduce Water Accounting Plus (WA+, which is a new framework designed to provide explicit spatial information on water depletion and net withdrawal processes in complex river basins. The influence of land use and landscape evapotranspiration on the water cycle is described explicitly by defining land use groups with common characteristics. WA+ presents four sheets including (i a resource base sheet, (ii an evapotranspiration sheet, (iii a productivity sheet, and (iv a withdrawal sheet. Every sheet encompasses a set of indicators that summarise the overall water resources situation. The impact of external (e.g., climate change and internal influences (e.g., infrastructure building can be estimated by studying the changes in these WA+ indicators. Satellite measurements can be used to acquire a vast amount of required data but is not a precondition for implementing WA+ framework. Data from hydrological models and water allocation models can also be used as inputs to WA+.
Directory of Open Access Journals (Sweden)
J. P. Burrows
2010-09-01
Full Text Available Hazardous impact of air pollutant emissions from megacities on atmospheric composition on regional and global scales is currently an important issue in atmospheric research. However, the quantification of emissions and related effects is frequently a difficult task, especially in the case of developing countries, due to the lack of reliable data and information. This study examines possibilities to retrieve multi-annual NOx emissions changes in megacity regions from satellite measurements of nitrogen dioxide and to quantify them in terms of linear and nonlinear trends. By combining the retrievals of the GOME and SCIAMACHY satellite instrument data with simulations performed by the CHIMERE chemistry transport model, we obtain the time series of NOx emission estimates for the 12 largest urban agglomerations in Europe and the Middle East in the period from 1996 to 2008. We employ then a novel method allowing estimation of a nonlinear trend in a noisy time series of an observed variable. The method is based on the probabilistic approach and the use of artificial neural networks; it does not involve any quantitative a priori assumptions. As a result, statistically significant nonlinearities in the estimated NOx emission trends are detected in 5 megacities (Bagdad, Madrid, Milan, Moscow and Paris. Statistically significant upward linear trends are detected in Istanbul and Tehran, while downward linear trends are revealed in Berlin, London and the Ruhr agglomeration. The presence of nonlinearities in NOx emission changes in Milan, Paris and Madrid is confirmed by comparison of simulated NOx concentrations with independent air quality monitoring data. A good quantitative agreement between the linear trends in the simulated and measured near surface NOx concentrations is found in London.
Testing statistical hypotheses of equivalence
Wellek, Stefan
2010-01-01
Equivalence testing has grown significantly in importance over the last two decades, especially as its relevance to a variety of applications has become understood. Yet published work on the general methodology remains scattered in specialists' journals, and for the most part, it focuses on the relatively narrow topic of bioequivalence assessment.With a far broader perspective, Testing Statistical Hypotheses of Equivalence provides the first comprehensive treatment of statistical equivalence testing. The author addresses a spectrum of specific, two-sided equivalence testing problems, from the
Fisenko, Anatoliy I
2014-01-01
Using polylogarithm functions the exact analytical expressions for the radiative and thermodynamic properties of blackbody radiation, such as the Wien displacement law, Stefan-Boltzmann law, total energy density, number density of photons, Helmholtz free energy density, internal energy density, enthalpy density, entropy density, heat capacity at constant volume, and pressure in the finite range of frequencies are constructed. The obtained expressions allow us to tabulate these functions in various finite frequency bands at different temperatures for practical applications. As an example, the radiative and thermodynamic functions using experimental data for the monopole spectrum of the Cosmic Microwave Background (CMB) radiation measured by the COBE FIRAS instrument in the 60 - 600 GHz frequency interval at the temperature T = 2.725 K are calculated. The expressions obtained for the radiative and thermodynamic functions can be easily presented in wavelength and wavenumber domains.
Ustinov, Eugene A.
2006-01-01
In a recent publication (Ustinov, 2002), we proposed an analytic approach to evaluation of radiative and geophysical weighting functions for remote sensing of a blackbody planetary atmosphere, based on general linearization approach applied to the case of nadir viewing geometry. In this presentation, the general linearization approach is applied to the limb viewing geometry. The expressions, similar to those obtained in (Ustinov, 2002), are obtained for weighting functions with respect to the distance along the line of sight. Further on, these expressions are converted to the expressions for weighting functions with respect to the vertical coordinate in the atmosphere. Finally, the numerical representation of weighting functions in the form of matrices of partial derivatives of grid limb radiances with respect to the grid values of atmospheric parameters is used for a convolution with the finite field of view of the instrument.
Zhang, Lei; Hao, Jiaming; Ye, Huapeng; Yeo, Swee Ping; Qiu, Min; Zouhdi, Said; Qiu, Cheng-Wei
2013-03-01
We propose a counter-intuitive mechanism of constructing an ultrathin broadband transparent device with two perfect blackbodies. By introducing hybridization of plasmon modes, resonant modes with different symmetries coexist in this system. A broadband transmission spectrum in the near infrared regime is achieved through controlling their coupling strengths, which is governed by the thickness of high refractive index layer. Meanwhile, the transparency bandwidth is found to be tunable in a large range by varying the geometric dimension. More significantly, from the point view of applications, the proposed method of achieving broadband transparency can perfectly tolerate the misalignment and asymmetry of periodic nanoparticles on the top and bottom, which is empowered by the unique dual of coupling-in and coupling-out processes within the pair of blackbodies. Moreover, roughness has little influence on its transmission performance. According to the coupled mode theory, the distinguished transmittance performance is physically interpreted by the radiative decay rate of the entire system. In addition to the feature of uniquely robust broadband transparency, such a ultrathin seamless nanostructure (in the presence of a uniform silver layer) also provides polarization-independent and angle-independent operations. Therefore, it may power up a wide spectrum of exciting applications in thin film protection, touch screen techniques, absorber-emitter transformation, etc.We propose a counter-intuitive mechanism of constructing an ultrathin broadband transparent device with two perfect blackbodies. By introducing hybridization of plasmon modes, resonant modes with different symmetries coexist in this system. A broadband transmission spectrum in the near infrared regime is achieved through controlling their coupling strengths, which is governed by the thickness of high refractive index layer. Meanwhile, the transparency bandwidth is found to be tunable in a large range by
Saponification equivalent of dasamula taila.
Saxena, R B
1994-07-01
Saponification equivalent values of Dasamula taila are very useful for the technical and analytical work. It gives the mean molecular weight of the glycerides and acids present in Dasamula Taila. Saponification equivalent values of Dasamula taila are reported in different packings.
Kother, L. K.; Hammer, M. D.; Finlay, C. C.; Olsen, N.
2014-12-01
We present a technique for modelling the lithospheric magnetic field based on estimation of equivalent potential field sources. As a first demonstration we present an application to magnetic field measurements made by the CHAMP satellite during the period 2009-2010. Three component vector field data are utilized at all latitudes. Estimates of core and large-scale magnetospheric sources are removed from the satellite measurements using the CHAOS-4 model. Quiet-time and night-side data selection criteria are also employed to minimize the influence of the ionospheric field. The model for the remaining lithospheric magnetic field consists of magnetic point sources (monopoles) arranged in an icosahedron grid with an increasing grid resolution towards the airborne survey area. The corresponding source values are estimated using an iteratively reweighted least squares algorithm that includes model regularization (either quadratic or maximum entropy) and Huber weighting. Data error covariance matrices are implemented, accounting for the dependence of data error variances on quasi-dipole latitudes. Results show good consistency with the CM5 and MF7 models for spherical harmonic degrees up to n = 95. Advantages of the equivalent source method include its local nature and the ease of transforming to spherical harmonics when needed. The method can also be applied in local, high resolution, investigations of the lithospheric magnetic field, for example where suitable aeromagnetic data is available. To illustrate this possibility, we present preliminary results from a case study combining satellite measurements and local airborne scalar magnetic measurements of the Norwegian coastline.
Unitary equivalence of quantum walks
Energy Technology Data Exchange (ETDEWEB)
Goyal, Sandeep K., E-mail: sandeep.goyal@ucalgary.ca [School of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X54001, 4000 Durban (South Africa); Konrad, Thomas [School of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X54001, 4000 Durban (South Africa); National Institute for Theoretical Physics (NITheP), KwaZulu-Natal (South Africa); Diósi, Lajos [Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, H-1525 Budapest 114, P.O.B. 49 (Hungary)
2015-01-23
Highlights: • We have found unitary equivalent classes in coined quantum walks. • A single parameter family of coin operators is sufficient to realize all simple one-dimensional quantum walks. • Electric quantum walks are unitarily equivalent to time dependent quantum walks. - Abstract: A simple coined quantum walk in one dimension can be characterized by a SU(2) operator with three parameters which represents the coin toss. However, different such coin toss operators lead to equivalent dynamics of the quantum walker. In this manuscript we present the unitary equivalence classes of quantum walks and show that all the nonequivalent quantum walks can be distinguished by a single parameter. Moreover, we argue that the electric quantum walks are equivalent to quantum walks with time dependent coin toss operator.
Bastiaanssen, W. G. M.; Cheema, M. J. M.; Immerzeel, W. W.; Miltenburg, I. J.; Pelgrum, H.
2012-11-01
The surface energy fluxes and related evapotranspiration processes across the Indus Basin were estimated for the hydrological year 2007 using satellite measurements. The new ETLook remote sensing model (version 1) infers information on actual Evaporation (E) and actual Transpiration (T) from combined optical and passive microwave sensors, which can observe the land-surface even under persistent overcast conditions. A two-layer Penman-Monteith equation was applied for quantifying soil and canopy evaporation. The novelty of the paper is the computation of E and T across a vast area (116.2 million ha) by using public domain microwave data that can be applied under all weather conditions, and for which no advanced input data are required. The average net radiation for the basin was estimated as being 112 Wm-2. The basin average sensible, latent and soil heat fluxes were estimated to be 80, 32, and 0 Wm-2, respectively. The average evapotranspiration (ET) and evaporative fraction were 1.2 mm d-1 and 0.28, respectively. The basin wide ET was 496 ± 16.8 km3 yr-1. Monte Carlo analysis have indicated 3.4% error at 95% confidence interval for a dominant land use class. Results compared well with previously conducted soil moisture, lysimeter and Bowen ratio measurements at field scale (R2 = 0.70; RMSE = 0.45 mm d-1; RE = -11.5% for annual ET). ET results were also compared against earlier remote sensing and modeling studies for various regions and provinces in Pakistan (R2 = 0.76; RMSE = 0.29 mmd-1; RE = 6.5% for annual ET). The water balance for all irrigated areas together as one total system in Pakistan and India (26.02 million ha) show a total ET value that is congruent with the ET value from the ETLook surface energy balance computations. An unpublished validation of the same ETLook model for 23 jurisdictional areas covering the entire Australian continent showed satisfactory results given the quality of the watershed data and the diverging physiographic and climatic
Full Static Output Feedback Equivalence
Directory of Open Access Journals (Sweden)
Aristotle G. Yannakoudakis
2013-01-01
Full Text Available We present a constructive solution to the problem of full output feedback equivalence, of linear, minimal, time-invariant systems. The equivalence relation on the set of systems is transformed to another on the set of invertible block Bezout/Hankel matrices using the isotropy subgroups of the full state feedback group and the full output injection group. The transformation achieving equivalence is calculated solving linear systems of equations. We give a polynomial version of the results proving that two systems are full output feedback equivalent, if and only if they have the same family of generalized Bezoutians. We present a new set of output feedback invariant polynomials that generalize the breakaway polynomial of scalar systems.
Tissue Engineered Human Skin Equivalents
Directory of Open Access Journals (Sweden)
Zheng Zhang
2012-01-01
Full Text Available Human skin not only serves as an important barrier against the penetration of exogenous substances into the body, but also provides a potential avenue for the transport of functional active drugs/reagents/ingredients into the skin (topical delivery and/or the body (transdermal delivery. In the past three decades, research and development in human skin equivalents have advanced in parallel with those in tissue engineering and regenerative medicine. The human skin equivalents are used commercially as clinical skin substitutes and as models for permeation and toxicity screening. Several academic laboratories have developed their own human skin equivalent models and applied these models for studying skin permeation, corrosivity and irritation, compound toxicity, biochemistry, metabolism and cellular pharmacology. Various aspects of the state of the art of human skin equivalents are reviewed and discussed.
Morita Equivalence for Factorisable Semigroups
Institute of Scientific and Technical Information of China (English)
Yu Qun CHEN; K. P. SHUM
2001-01-01
Recall that the semigroups S and R are said to be strongly Morita equivalent if there exists a unitary Morita context (S,R,S PR,RQs, <, []) with < and [] surjective. For a factorisable semigroup S, we denote s = {(s1, s2) ∈ S× S | ss1 =ss2,s ∈ S}, S＇ = S/s and US-FAct= {sM ∈S- Act|SM = M and SHoms(S, M) ≌ M}. We show that, for factorisable semigroups S and R, the categories US-FAct and UR-FAct are equivalent if and only if the semigroups S＇ and R＇ are strongly Morita equivalent. Some conditions for a factorisable semigroup to be strongly Morita equivalent to a sandwich semigroup, local units semigroup, monoid and group separately are also given. Moreover, we show that a semigroup S is completely simple if and only if S is strongly Morita equivalent to a group and for any index set I, S SHoms(S,Ⅱi∈ S)→Ⅱi∈S, s t·f→(st)f is an S-isomorphism.
Safronova, U I; Johnson, W R
2016-01-01
Energy levels of 30 low-lying states of Lu2+ and allowed electric-dipole matrix elements between these states are evaluated using a relativistic all-order method in which all single, double and partial triple excitations of Dirac-Fock wave functions are included to all orders of perturbation theory. Matrix elements are critically evaluated for their accuracy and recommended values of the matrix elements are given together with uncertainty estimates. Line strengths, transition rates and lifetimes of the metastable 5d(3/2) and 5d(5/2) states are calculated. Recommended values are given for static polarizabilities of the 6s, 5d and 6p states and tensor polarizabilities of the 5d and 6p(3/2) states. Uncertainties of the polarizability values are estimated in all cases. The blackbody radiation shift of the 6s(1/2)-5d(5/2) transition frequency of the Lu2+ ion is calculated with the aid of the recommended scalar polarizabilities of the 6s(1/2) and 5d(5/2) states. Finally, A and B hyperfine constants are determined f...
Safronova, U. I.; Safronova, M. S.; Johnson, W. R.
2016-09-01
Energy levels of 30 low-lying states of Lu2 + and allowed electric-dipole matrix elements between these states are evaluated using a relativistic all-order method in which all single, double, and partial triple excitations of Dirac-Fock wave functions are included to all orders of perturbation theory. Matrix elements are critically evaluated for their accuracy and recommended values of the matrix elements are given together with uncertainty estimates. Line strengths, transition rates, and lifetimes of the metastable 5 d3 /2 and 5 d5 /2 states are calculated. Recommended values are given for static polarizabilities of the 6 s , 5 d , and 6 p states and tensor polarizabilities of the 5 d and 6 p3 /2 states. Uncertainties of the polarizability values are estimated in all cases. The blackbody radiation shift of the 6 s1 /2-5 d5 /2 transition frequency of the Lu2 + ion is calculated with the aid of the recommended scalar polarizabilities of the 6 s1 /2 and 5 d5 /2 states. Finally, A and B hyperfine constants are determined for states of 2+175Lu with n ≤9 . This work provides recommended values of transition matrix elements, polarizabilities, and hyperfine constants of Lu2 +, critically evaluated for accuracy, for benchmark tests of high-precision theoretical methodology and planning of future experiments.
Matching of equivalent field regions
DEFF Research Database (Denmark)
Appel-Hansen, Jørgen; Rengarajan, S.B.
2005-01-01
screen, having the same homogeneous medium on both sides and an impressed current on one aide, an alternative procedure is relevant. We make use of the fact that in the aperture the tangential component of the magnetic field due to the induced currents in the screen is zero. The use of such a procedure......In aperture problems, integral equations for equivalent currents are often found by enforcing matching of equivalent fields. The enforcement is made in the aperture surface region adjoining the two volumes on each side of the aperture. In the case of an aperture in a planar perfectly conducting...... shows that equivalent currents can be found by a consideration of only one of the two volumes into which the aperture plane divides the space. Furthermore, from a consideration of an automatic matching at the aperture, additional information about tangential as well as normal field components...
Teleparallel Equivalent of Lovelock Gravity
Gonzalez, P A
2015-01-01
There is a growing interest in modified gravity theories based on torsion due to these theories prove to exhibit interesting cosmological implications. In this work, inspired by the teleparallel formulation of General Relativity we present its extension to Lovelock Gravity known as the most natural extension of general relativity in higher-dimensional spacetimes. First, we review Teleparallel Equivalent of General Relativity and Teleparallel Equivalent of Gauss-Bonnet Gravity, and then we construct Teleparallel Equivalent of Lovelock Gravity. In order to achieve this goal we use the vielbein and the connection, without imposing the Weitzenb\\"ock connection. Then, we extract the teleparallel formulation of the theory by setting the curvature to be null.
Mathematically Equivalent, Computationally Non-equivalent Formulas and Software Comprehensibility
2016-06-07
and Software Comprehensibility Marvin J. Goldstein Surface Ship Sonar Department Approved for public release; distribution unlimited Report...equivalent Formulas and Software Comprehensibility 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Marvin Goldstein...13. SUPPLEMENTARY NOTES NUWC2015 14. ABSTRACT In the development of mathematical software , often the formula that defines the mathematical purpose
Teleparallel equivalent of Lovelock gravity
González, P. A.; Vásquez, Yerko
2015-12-01
There is a growing interest in modified gravity theories based on torsion, as these theories exhibit interesting cosmological implications. In this work inspired by the teleparallel formulation of general relativity, we present its extension to Lovelock gravity known as the most natural extension of general relativity in higher-dimensional space-times. First, we review the teleparallel equivalent of general relativity and Gauss-Bonnet gravity, and then we construct the teleparallel equivalent of Lovelock gravity. In order to achieve this goal, we use the vielbein and the connection without imposing the Weitzenböck connection. Then, we extract the teleparallel formulation of the theory by setting the curvature to null.
Acquired Equivalence Changes Stimulus Representations
Meeter, M.; Shohamy, D.; Myers, C. E.
2009-01-01
Acquired equivalence is a paradigm in which generalization is increased between two superficially dissimilar stimuli (or antecedents) that have previously been associated with similar outcomes (or consequents). Several possible mechanisms have been proposed, including changes in stimulus representations, either in the form of added associations or…
USEPA PATHOGEN EQUIVALENCY COMMITTEE RETREAT
The Pathogen Equivalency Committee held its retreat from September 20-21, 2005 at Hueston Woods State Park in College Corner, Ohio. This presentation will update the PEC’s membership on emerging pathogens, analytical methods, disinfection techniques, risk analysis, preparat...
Comments on field equivalence principles
DEFF Research Database (Denmark)
Appel-Hansen, Jørgen
1987-01-01
It is pointed Out that often-used arguments based on a short-circuit concept in presentations of field equivalence principles are not correct. An alternative presentation based on the uniqueness theorem is given. It does not contradict the results obtained by using the short-circuit concept...
National Research Council Canada - National Science Library
Carpentier, Franck; Smeets, Paul M; Barnes-Holmes, Dermot; Stewart, Ian
2004-01-01
... (equivalence-equivalence). Similar performances are required in classical analogies (a : b :: c : d). Therefore, some researchers have argued that equivalence-equivalence can serve as a behavior analytic model for analogical reasoning...
EQUIVALENCE VERSUS NON-EQUIVALENCE IN ECONOMIC TRANSLATION
Directory of Open Access Journals (Sweden)
Cristina, Chifane
2012-01-01
Full Text Available This paper aims at highlighting the fact that “equivalence” represents a concept worth revisiting and detailing upon when tackling the translation process of economic texts both from English into Romanian and from Romanian into English. Far from being exhaustive, our analysis will focus upon the problems arising from the lack of equivalence at the word level. Consequently, relevant examples from the economic field will be provided to account for the following types of non-equivalence at word level: culturespecific concepts; the source language concept is not lexicalised in the target language; the source language word is semantically complex; differences in physical and interpersonal perspective; differences in expressive meaning; differences in form; differences in frequency and purpose of using specific forms and the use of loan words in the source text. Likewise, we shall illustrate a number of translation strategies necessary to deal with the afore-mentioned cases of non-equivalence: translation by a more general word (superordinate; translation by a more neutral/less expressive word; translation by cultural substitution; translation using a loan word or loan word plus explanation; translation by paraphrase using a related word; translation by paraphrase using unrelated words; translation by omission and translation by illustration.
Equivalence problem for Bishop surfaces
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
The paper has two parts. We first briefly survey recent studies on the equivalence problem for real submanifolds in a complex space under the action of biholomorphic transformations. We will mainly focus on some of the recent studies of Bishop surfaces, which, in particular, includes the work of the authors. In the second part of the paper, we apply the general theory developed by the authors to explicitly classify an algebraic family of Bishop surfaces with a vanishing Bishop invariant. More precisely, we let M be a real submanifold of C 2 defined by an equation of the form w = zz + 2Re(z s + az s+1 ) with s≥ 3 and a a complex parameter. We will prove in the second part of the paper that for s≥ 4 two such surfaces are holomorphically equivalent if and only if the parameter differs by a certain rotation. When s = 3, we show that surfaces of this type with two different real parameters are not holomorphically equivalent.
Equivalent statistics and data interpretation.
Francis, Gregory
2016-10-14
Recent reform efforts in psychological science have led to a plethora of choices for scientists to analyze their data. A scientist making an inference about their data must now decide whether to report a p value, summarize the data with a standardized effect size and its confidence interval, report a Bayes Factor, or use other model comparison methods. To make good choices among these options, it is necessary for researchers to understand the characteristics of the various statistics used by the different analysis frameworks. Toward that end, this paper makes two contributions. First, it shows that for the case of a two-sample t test with known sample sizes, many different summary statistics are mathematically equivalent in the sense that they are based on the very same information in the data set. When the sample sizes are known, the p value provides as much information about a data set as the confidence interval of Cohen's d or a JZS Bayes factor. Second, this equivalence means that different analysis methods differ only in their interpretation of the empirical data. At first glance, it might seem that mathematical equivalence of the statistics suggests that it does not matter much which statistic is reported, but the opposite is true because the appropriateness of a reported statistic is relative to the inference it promotes. Accordingly, scientists should choose an analysis method appropriate for their scientific investigation. A direct comparison of the different inferential frameworks provides some guidance for scientists to make good choices and improve scientific practice.
21 CFR 26.9 - Equivalence determination.
2010-04-01
... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Equivalence determination. 26.9 Section 26.9 Food... Specific Sector Provisions for Pharmaceutical Good Manufacturing Practices § 26.9 Equivalence determination... document insufficient evidence of equivalence, lack of opportunity to assess equivalence or a determination...
1974-06-01
didiroinate solution, etc. Talk 7. Ham. of materials (Dirbaim mite) Raw tel 1,550 Gls 2,00O Chromium 3,100 Alumhinhim so Aluminium anodic oxide film...Zirconium Copper, Hard ............. 980 56 Nitidng te Is & T. ......... D6 21 Hafnium . Ann........... .............. 7 - Nickel-Base Supeallt&s 5.1’n Tr...55 so Heat Resistant Alloys (cast). Ht Tr .. 15]i 73 Leaded Commercial Bronze. Hailf Hard 55 - Vanadium & Hafnium . OW
at the indicated wavelength and temperature, Planck’s equation. This equation represents the monochromatic radiant intensity at a particular wavelength from a perfect radiator maintained at the indicated temperature.
On the Translation Equivalence of Literature Works
Institute of Scientific and Technical Information of China (English)
吴娟
2013-01-01
As for translation principle, people have different opinions. The principle of equivalent translation may be is one of the most reason-able ones in today's translation world in my eyes. This paper focuses on the possibility and thec ondition to be achieved the biggest equivalence of the semantic, pragmatic and culture in order to get the conclusion that the translation equivalence is the proper principle. Besides,this paper has also discussed the pragmatic equivalence and cultural equivalence.
On the Translation Equivalence of Literature Works
Institute of Scientific and Technical Information of China (English)
吴娟
2013-01-01
As for translation principle,people have different opinions.The principle of equivalent translation maybe is one of the most reasonable ones in today’s translation world in my eyes.This paper focuses on the possibility and the condition to be achieved the biggest equivalence of the semantic,pragmatic and culture in order to get the conclusion that the translation equivalence is the proper principle.Besides,this paper has also discussed the pragmatic equivalence and cultural equivalence.
On an equivalence of fuzzy subgroups III
Directory of Open Access Journals (Sweden)
V. Murali
2003-01-01
Full Text Available This paper is the third in a series of papers studying equivalence classes of fuzzy subgroups of a given group under a suitable equivalence relation. We introduce the notion of a pinned flag in order to study the operations sum, intersection and union, and their behavior with respect to the equivalence. Further, we investigate the extent to which a homomorphism preserves the equivalence. Whenever the equivalences are not preserved, we have provided suitable counterexamples.
Conformal dynamical equivalence and applications
Spyrou, N. K.
2011-02-01
The "Conformal Dynamical Equivalence" (CDE) approach is briefly reviewed, and some of its applications, at various astrophysical levels (Sun, Solar System, Stars, Galaxies, Clusters of Galaxies, Universe as a whole), are presented. According to the CDE approach, in both the Newtonian and general-relativistic theories of gravity, the isentropic hydrodynamic flows in the interior of a bounded gravitating perfect-fluid source are dynamically equivalent to geodesic motions in a virtual, fully defined fluid source. Equivalently, the equations of hydrodynamic motion in the former source are functionally similar to those of the geodesic motions in the latter, physically, fully defined source. The CDE approach is followed for the dynamical description of the motions in the fluid source. After an observational introduction, taking into account all the internal physical characteristics of the corresponding perfect-fluid source, and based on the property of the isentropic hydrodynamic flows (quite reasonable for an isolated physical system), we examine a number of issues, namely, (i) the classical Newtonian explanation of the celebrated Pioneer-Anomaly effect in the Solar System, (ii) the possibility of both the attractive gravity and the repulsive gravity in a non-quantum Newtonian framework, (iii) the evaluation of the masses - theoretical, dynamical, and missing - and of the linear dimensions of non-magnetized and magnetized large-scale cosmological structures, (iv) the explanation of the flat-rotation curves of disc galaxies, (v) possible formation mechanisms of winds and jets, and (vi) a brief presentation of a conventional approach - toy model to the dynamics of the Universe, characterized by the dominant collisional dark matter (with its subdominant luminous baryonic "contamination"), correctly interpreting the cosmological observational data without the need of the notions dark energy, cosmological constant, and universal accelerating expansion.
Equivalence principle in Chameleon models .
Kraiselburd, L.; Landau, S.; Salgado, M.; Sudarsky, D.
Most theories that predict time and/or space variation of fundamental constants also predict violations of the Weak Equivalence Principle (WEP). Khoury and Weltmann proposed the chameleon model in 2004 and claimed that this model avoids experimental bounds on WEP. We present a contrasting view based on an approximate calculation of the two body problem for the chameleon field and show that the force depends on the test body composition. Furthermore, we compare the prediction of the force on a test body with Eötvös type experiments and find that the chameleon field effect cannot account for current bounds.
Thermodynamic equivalence of spin systems
Energy Technology Data Exchange (ETDEWEB)
Beltman, J.M. (Katholieke Universiteit Nijmegen (Netherlands))
1975-01-01
The thermodynamic equilibrium properties of systems composed of classical spin /sup 1///sub 2/ particles (Ising spins) are studied. Given an interaction pattern between the Ising spins the main problem is to calculate the equilibrium state(s) of the system. The point put forward here is the existence of many thermodynamical equivalent spin coordinate systems. As a consequence of this phenomenon the interaction pattern of a system may be very intricate when described with respect to one spin coordinate system whereas it may become simple with respect to another one and vice versa. A systematic investigation of this phenomenon is made. (FR)
Blast Wave Characteristics and Equivalency
Sochet, Isabelle; Schneider, Helmut
2010-01-01
ISBN 978-5-94588-079-5; The characteristics of blast waves generated by detonation of gas clouds are studies theoretically and validated by both small-scale and large-scale experiments with ethylene-air mixtures of different equivalence ratio. The mixtures were confined in hemispherical or spherical balloons made from thin polyethylene foils of 0.75 m³ and 15 m³ in volume. The detonation of gas mixtures was initiated by a solid explosive. The characteristics of the blast wave in terms of over...
Equivalence Principle in Chameleon Models
Kraiselburd, Lucila; Salgado, Marcelo; Sudarsky, Daniel
2013-01-01
Most theories that predict time and/or space variation of fundamental constants also predict violations of the Weak Equivalence Principle (WEP). Khoury and Weltmann proposed the chameleon model in 2004 and claimed that this model avoids experimental bounds on WEP. We present a contrasting view based on an approximate calculation of the two body problem for the chameleon field and show that the force depends on the test body composition. Furthermore, we compare the prediction of the force on a test body with E\\"otv\\"os type experiments and find that the chameleon field effect cannot account for current bounds.
On Vasyliunas's equivalent conductivity formalism
Pontius, D. H., Jr.
1992-01-01
The Vasyliunas's (1972) equivalent conductivity formalism (ECF) for representing the coupling of the ionosphere and the magnetosphere is discussed, and a new, simpler, derivation is presented of the ECF, in which certain of the underlying assumptions and their implications are made transparent. The derivation presented indicates that the only role of the ions in the ECF is to insure quasi-neutrality. It is shown that the ECF is not as robust as usually assumed and that caution must be used to insure that reasonable results are obtained.
Schiller, Stephan; Bekbaev, Ashat K; Korobov, Vladimir I
2014-01-01
We calculate the DC Stark effect for three molecular hydrogen ions in the non-relativistic approximation. The effect is calculated both in dependence on the rovibrational state and in dependence on the hyperfine state. We discuss special cases and approximations. We also calculate the AC polarisabilities for several rovibrational levels, and therefrom evaluate accurately the black-body radiation shift, including the effects of excited electronic states. The results enable the detailed evaluation of certain systematic shifts of the transitions frequencies for the purpose of ultra-high-precision optical, microwave or radio-frequency spectroscopy in ion traps.
Schiller, S.; Bakalov, D.; Bekbaev, A. K.; Korobov, V. I.
2014-05-01
We calculate the dc Stark effect for three molecular hydrogen ions in the nonrelativistic approximation. The effect is calculated both in dependence on the rovibrational state and in dependence on the hyperfine state. We discuss special cases and approximations. We also calculate the ac polarizabilities for several rovibrational levels and therefrom evaluate accurately the blackbody radiation shift, including the effects of excited electronic states. The results enable the detailed evaluation of certain systematic shifts of the transitions frequencies for the purpose of ultrahigh-precision optical, microwave, or radio-frequency spectroscopy in ion traps.
Shalygin, V. A.; Vorobjev, L. E.; Firsov, D. A.; Sofronov, A. N.; Melentyev, G. A.; Lundin, W. V.; Nikolaev, A. E.; Sakharov, A. V.; Tsatsulnikov, A. F.
2011-04-01
The authors report on the observation and study of terahertz radiation emission from modulation-doped AlGaN/GaN heterostructure under conditions of heating of a two-dimensional electron gas in the lateral electric field. The experimental results are compared with the theoretical model of blackbody-like emission from hot two-dimensional electrons. Complementary transport measurements and a theoretical simulation were carried out to determine the dependence of effective electron temperature on electric field. The role of nonequilibrium optical phonon accumulation is discussed.
Einstein's equivalence principle in cosmology
Kopeikin, Sergei M
2013-01-01
We study physical consequences of the Einstein equivalence principle (EEP) for a Hubble observer in FLRW universe. We introduce the local inertial coordinates with the help of a special conformal transformation. The local inertial metric is Minkowski flat and materialized by a congruence of time-like geodesics of static observers. The static observers are equipped with the ideal clocks measuring the proper time that is synchronized with the clocks of the Hubble observer. The local inertial metric is used for physical measurements of spacetime intervals with the ideal clocks and rulers. The special conformal transformation preserves null geodesics but does not keep invariant time-like geodesics. Moreover, it makes the rate of the local time coordinate dependent on velocity of the particle which makes impossible to rich the uniform parameterization of the world lines of static observers and light geodesics with a single parameter - they differ by the conformal factor of FLRW metric. The most convenient way to s...
ROMANIC EQUIVALENTS FOR LATIN IDIOMS
Directory of Open Access Journals (Sweden)
Dr. Stefan DUMITRU
2010-11-01
Full Text Available In this study we set forth to present several of the most important aspects regarding the contrastive analysis of a well-defined number of Latin idioms in parallel with their Romanic counterparts (in French, Italian, Spanish and Romanian. Our intent was not to discover, in the Romanic space, all the equivalents of the phrases that form the corpus we work with, for reasons pertaining to material restrictions, but to discuss, based on a certain number of units, the different types of issues they may point to. The most important is to establish the relation between the idiomatic expressions in Latin and their correspondents in the above mentioned languages, regarding their inner form, their meaning and their structure.
Electroweak Vortices and Gauge Equivalence
MacDowell, Samuel W.; Törnkvist, Ola
Vortex configurations in the electroweak gauge theory are investigated. Two gauge-inequivalent solutions of the field equations, the Z and W vortices, have previously been found. They correspond to embeddings of the Abelian Nielsen-Olesen vortex solution into a U(1) subgroup of SU(2)×U(1). It is shown here that any electroweak vortex solution can be mapped into a solution of the same energy with a vanishing upper component of the Higgs field. The correspondence is a gauge equivalence for all vortex solutions except those for which the winding numbers of the upper and lower Higgs components add to zero. This class of solutions, which includes the W vortex, corresponds to a singular solution in the one-component gauge. The results, combined with numerical investigations, provide an argument against the existence of other vortex solutions in the gauge-Higgs sector of the Standard Model.
Expanding the Interaction Equivalency Theorem
Directory of Open Access Journals (Sweden)
Brenda Cecilia Padilla Rodriguez
2015-06-01
Full Text Available Although interaction is recognised as a key element for learning, its incorporation in online courses can be challenging. The interaction equivalency theorem provides guidelines: Meaningful learning can be supported as long as one of three types of interactions (learner-content, learner-teacher and learner-learner is present at a high level. This study sought to apply this theorem to the corporate sector, and to expand it to include other indicators of course effectiveness: satisfaction, knowledge transfer, business results and return on expectations. A large Mexican organisation participated in this research, with 146 learners, 30 teachers and 3 academic assistants. Three versions of an online course were designed, each emphasising a different type of interaction. Data were collected through surveys, exams, observations, activity logs, think aloud protocols and sales records. All course versions yielded high levels of effectiveness, in terms of satisfaction, learning and return on expectations. Yet, course design did not dictate the types of interactions in which students engaged within the courses. Findings suggest that the interaction equivalency theorem can be reformulated as follows: In corporate settings, an online course can be effective in terms of satisfaction, learning, knowledge transfer, business results and return on expectations, as long as (a at least one of three types of interaction (learner-content, learner-teacher or learner-learner features prominently in the design of the course, and (b course delivery is consistent with the chosen type of interaction. Focusing on only one type of interaction carries a high risk of confusion, disengagement or missed learning opportunities, which can be managed by incorporating other forms of interactions.
Equivalent damage of loads on pavements
CSIR Research Space (South Africa)
Prozzi, JA
2009-05-26
Full Text Available This report describes a new methodology for the determination of Equivalent Damage Factors (EDFs) of vehicles with multiple axle and wheel configurations on pavements. The basic premise of this new procedure is that "equivalent pavement response...
Discovering Classes of Strongly Equivalent Logic Programs
Chen, Y.; Lin, F.
2011-01-01
In this paper we apply computer-aided theorem discovery technique to discover theorems about strongly equivalent logic programs under the answer set semantics. Our discovered theorems capture new classes of strongly equivalent logic programs that can lead to new program simplification rules that preserve strong equivalence. Specifically, with the help of computers, we discovered exact conditions that capture the strong equivalence between a rule and the empty set, between two rules, between t...
Classroom Activities for Introducing Equivalence Relations
Brandt, Jim
2013-01-01
Equivalence relations and partitions are two interconnected ideas that play important roles in advanced mathematics. While students encounter the informal notion of equivalence in many courses, the formal definition of an equivalence relation is typically introduced in a junior level transition-to-proof course. This paper reports the results of a…
Equivalence Principle in Chameleon Models
Kraiselburd, Lucila; Salgado, Marcelo; Sudarsky, Daniel; Vucetich, Héctor
2015-01-01
Most theories that predict time and(or) space variation of fundamental constants also predict violations of the Weak Equivalence Principle (WEP). Khoury and Weltman proposed the chameleon model in 2004 and claimed that this model avoids experimental bounds on the WEP. In this paper we present a contrasting view based on the analysis of the force between two bodies induced by the chameleon field using a particular approach in which the field due to both the large and the small bodies is obtained by appropriate series expansions in the various regions of interest and the corresponding matching conditions. We found that resulting force depends on the test body\\'{}s composition even when the chameleon coupling constants $\\beta_{i}$ are universal. In particular, we compared the resulting differential acceleration of test bodies made of Be and Al with the corresponding bounds obtained from E\\"otv\\"os type experiments and find that the predictions of the chameleon model are, in general, various orders of magnitude a...
Testing the weak equivalence principle
Nobili, Anna M.; Comandi, Gian Luca; Pegna, Raffaello; Bramanti, Donato; Doravari, Suresh; Maccarone, Francesco; Lucchesi, David M.
2010-01-01
The discovery of Dark Energy and the fact that only about 5% of the mass of the universe can be explained on the basis of the current laws of physics have led to a serious impasse. Based on past history, physics might indeed be on the verge of major discoveries; but the challenge is enormous. The way to tackle it is twofold. On one side, scientists try to perform large scale direct observations and measurements - mostly from space. On the other, they multiply their efforts to put to the most stringent tests ever the physical theories underlying the current view of the physical world, from the very small to the very large. On the extremely small scale very exciting results are expected from one of the most impressive experiments in the history of mankind: the Large Hadron Collider. On the very large scale, the universe is dominated by gravity and the present impasse undoubtedly calls for more powerful tests of General Relativity - the best theory of gravity to date. Experiments testing the Weak Equivalence Principle, on which General Relativity ultimately lies, have the strongest probing power of them all; a breakthrough in sensitivity is possible with the “Galileo Galilei” (GG) satellite experiment to fly in low Earth orbit.
Equivalent Simplification Method of Micro-Grid
Directory of Open Access Journals (Sweden)
Cai Changchun
2013-09-01
Full Text Available The paper concentrates on the equivalent simplification method for the micro-grid system connection into distributed network. The equivalent simplification method proposed for interaction study between micro-grid and distributed network. Micro-grid network, composite load, gas turbine synchronous generation, wind generation are equivalent simplification and parallel connect into the point of common coupling. A micro-grid system is built and three phase and single phase grounded faults are performed for the test of the equivalent model of micro-grid. The simulation results show that the equivalent model of micro-grid is effective, and the dynamic of equivalent model is similar with the detailed model of micro-grid. The equivalent simplification method for the micro-grid network and distributed components is suitable for the study of micro-grid.
Pavolonis, Michael J.; Sieglaff, Justin; Cintineo, John
2015-08-01
While satellites are a proven resource for detecting and tracking volcanic ash and dust clouds, existing algorithms for automatically detecting volcanic ash and dust either exhibit poor overall skill or can only be applied to a limited number of sensors and/or geographic regions. As such, existing techniques are not optimized for use in real-time applications like volcanic eruption alerting and data assimilation. In an effort to significantly improve upon existing capabilities, the Spectrally Enhanced Cloud Objects (SECO) algorithm was developed. The SECO algorithm utilizes a combination of radiative transfer theory, a statistical model, and image processing techniques to identify volcanic ash and dust clouds in satellite imagery with a very low false alarm rate. This fully automated technique is globally applicable (day and night) and can be adapted to a wide range of low earth orbit and geostationary satellite sensors or even combinations of satellite sensors. The SECO algorithm consists of four primary components: conversion of satellite measurements into robust spectral metrics, application of a Bayesian method to estimate the probability that a given satellite pixel contains volcanic ash and/or dust, construction of cloud objects, and the selection of cloud objects deemed to have the physical attributes consistent with volcanic ash and/or dust clouds. The first two components of the SECO algorithm are described in this paper, while the final two components are described in a companion paper.
Davis, S. M.; Rosenlof, K. H.; Hurst, D. F.; Hassler, B.; Read, W. G.
2015-12-01
Vertical profiles of ozone and humidity from the upper troposphere to stratosphere have been retrieved from a number of limb sounding and solar occultation satellite instruments since the 1980's. In particular, measurements from the SAGE instruments, UARS MLS, UARS HALOE, and most recently Aura MLS, have provided overlapping data since 1984. In order to quantify interannual- to decadal-scale variability in water vapor and ozone, it is necessary to have a uniform and homogenous record over the period of interest. With this in mind, we merged the aforementioned satellite measurements to create the Stratospheric Water and Ozone Satellite Homogenized (SWOOSH) data set, which contains vertically resolved zonal-mean (2.5°) monthly-mean water vapor and ozone concentration at levels covering the stratosphere. In this presentation, we describe the process of merging the satellite data sets, which involves adjusting the data to a reference measurement using offsets calculated from coincident observations taken during instrument overlap periods. Uncertainties associated with individual measurement precision, geophysical variability, and the merging process are quantified and compared to one another. We show that while the SWOOSH data can be used to quantify interannual variability, quantifying long-term trends in SWOOSH is complicated by the various sources of uncertainty, as well as by potential drifts of individual instruments. The issue of satellite-derived trends is discussed in relation to the long-term record of balloon-borne frostpoint hygrometer measurements from Boulder, CO.
Metabolic equivalents during scooter exercise.
Kijima, Akira; Arimoto, Morio; Muramatsu, Shigeru
2007-06-01
The purpose of this study was to determine the metabolic equivalents (METs) for scooter exercise (riding a scooter, scootering) and to examine the energy expenditure and the heart rate response, so that the results can be used in health promotion activities. Eighteen young adults (10 males and 8 females) participated in scootering on a treadmill at three different speeds for six minutes each. Before, during, and after the exercise, pulmonary ventilation, oxygen uptake (VO(2)), carbon dioxide product, respiratory exchange ratio (R), and heart rate (HR) were measured. These measurements kept steady states from the 3rd to 6th minute of each different speed session. The MET values acquired during scootering at 80 m.min(-1), 110 m.min(-1), and 140 m.min(-1) were 3.9, 4.3, and 5.0, respectively. Calculated using VO(2) (ml.kg(-1).min(-1))x[4.0+R], the energy consumption for scootering at each speed was 67.0+/-10.6, 73.3+/-10.2, and 84.8+/-7.9 cal.kg(-1).min(-1), respectively. The regression equation between scootering speed (X, m.min(-1)) and VO(2) (Y, ml.kg(-1).min(-1)) is Y=0.062X+8.655, and the regression equation between HR (X, beats.min(-1)) and VO(2)reserve (Y, %) is Y=0.458X-11.264. These equations can be applied to both females and males. Thus, scootering at 80 to 140 m.min(-1) might not be sufficient to improve the cardiorespiratory fitness of young male adults similar to the participants, but it may contribute many healthy benefits to most female adults and even male adults, and improve their health and fitness at the faster speeds.
INVARIANTS UNDER STABLE EQUIVALENCES OF MORITA TYPE
Institute of Scientific and Technical Information of China (English)
Li Fang; Sun Longgang
2012-01-01
The aim of this article is to study some invariants of associative algebras under stable equivalences of Morita type.First of all,we show that,if two finite-dimensional selfinjective k-algebras are stably equivalent of Morita type,then their orbit algebras are isomorphic.Secondly,it is verified that the quasitilted property of an algebra is invariant under stable equivalences of Morita type.As an application of this result,it is obtained that if an algebra is of finite representation type,then its tilted property is invariant under stable equivalences of Morita type; the other application to partial tilting modules is given in Section 4. Finally,we prove that when two finite-dimensional k-algebras are stably equivalent of Morita type,their repetitive algebras are also stably equivalent of Morita type under certain conditions.
The Complexity of Identifying Large Equivalence Classes
DEFF Research Database (Denmark)
Skyum, Sven; Frandsen, Gudmund Skovbjerg; Miltersen, Peter Bro
1999-01-01
We prove that at least 3k−4/k(2k−3)(n/2) – O(k)equivalence tests and no more than 2/k (n/2) + O(n) equivalence tests are needed in the worst case to identify the equivalence classes with at least k members in set of n elements. The upper bound is an improvement by a factor 2 compared to known res...
Homogeneous Dielectric Equivalents of Composite Material Shields
Directory of Open Access Journals (Sweden)
P. Tobola
2009-04-01
Full Text Available The paper deals with the methodology of replacing complicated parts of an airplane skin by simple homogeneous equivalents, which can exhibit similar shielding efficiency. On one hand, the airplane built from the virtual homogeneous equivalents can be analyzed with significantly reduced CPU-time demands and memory requirements. On the other hand, the equivalent model can estimate the internal fields satisfactory enough to evaluate the electromagnetic immunity of the airplane.
Equivalent Simplification Method of Micro-Grid
Cai Changchun; Cao Xiangqin
2013-01-01
The paper concentrates on the equivalent simplification method for the micro-grid system connection into distributed network. The equivalent simplification method proposed for interaction study between micro-grid and distributed network. Micro-grid network, composite load, gas turbine synchronous generation, wind generation are equivalent simplification and parallel connect into the point of common coupling. A micro-grid system is built and three phase and single phase grounded faults are per...
equivalency/majorly/market share,etc.
Institute of Scientific and Technical Information of China (English)
张福基
1998-01-01
equivalency n. a level of achievement equivalent to completion of an educational or trainingprogram。同等学历(相当于完成某一教育或训练计划的学业成绩水平):a highschool equivalency certificate中学同等学历证书。注意不能用equivalence。majorly[’meid??li]adv.[1956
21 CFR 26.6 - Equivalence assessment.
2010-04-01
... OF PHARMACEUTICAL GOOD MANUFACTURING PRACTICE REPORTS, MEDICAL DEVICE QUALITY SYSTEM AUDIT REPORTS... Specific Sector Provisions for Pharmaceutical Good Manufacturing Practices § 26.6 Equivalence...
Approximate equivalence in von Neumann algebras
Institute of Scientific and Technical Information of China (English)
DING; Huiru; Don; Hadwin
2005-01-01
One formulation of D. Voiculescu's theorem on approximate unitary equivalence is that two unital representations π and ρ of a separable C*-algebra are approximately unitarily equivalent if and only if rank o π = rank o ρ. We study the analog when the ranges of π and ρ are contained in a von Neumann algebra R, the unitaries inducing the approximate equivalence must come from R, and "rank" is replaced with "R-rank" (defined as the Murray-von Neumann equivalence of the range projection).
Directory of Open Access Journals (Sweden)
C. Paton-Walsh
2010-06-01
Full Text Available In this paper we describe a new method for estimating trace gas emissions from large vegetation fires using satellite measurements of aerosol optical depth (AOD at 550 nm, combined with an atmospheric chemical transport model. The method uses a threshold value to screen out normal levels of AOD that may be caused by raised dust, sea salt aerosols or diffuse smoke transported from distant fires. Using this method we infer an estimated total emission of 15±5 Tg of carbon monoxide, 0.05±0.02 Tg of hydrogen cyanide, 0.11±0.03 Tg of ammonia, 0.25±0.07 Tg of formaldehyde, 0.03±0.01 of acetylene, 0.10±0.03 Tg of ethylene, 0.03±0.01 Tg of ethane, 0.21±0.06 Tg of formic acid and 0.28±0.09 Tg of methanol released to the atmosphere from the Canberra fires of 2003. An assessment of the uncertainties in the new method is made and we show that our estimate agrees (within expected uncertainties with estimates made using current conventional methods of multiplying together factors for the area burned, fuel load, the combustion efficiency and the emission factor for carbon monoxide. A simpler estimate derived directly from the satellite AOD measurements is also shown to be in agreement with conventional estimates, suggesting that the method may, under certain meteorological conditions, be applied without the complication of using a chemical transport model. The new method is suitable for estimating emissions from distinct large fire episodes and although it has some significant uncertainties, these are largely independent of the uncertainties inherent in conventional techniques. Thus we conclude that the new method is a useful additional tool for characterising emissions from vegetation fires.
Leigh, R. J.; Corlett, G. K.; Monks, P. S.
2003-04-01
Knowledge of stratospheric ozone trends is vital both for interpretation of the current record of surface temperature variation and for prediction of future patterns of climate evolution. Historically, data records from the TOMS satellite instruments and the Dobson ground-based networks have provided the premier standard for analysis, although recent work has invested much effort in deriving combined TOMS and GOME datasets. Despite problems of calibration and systematic uncertainties, the satellite data record has been valuable in demonstrating trends in total ozone as a function of latitude and month. Perhaps most critically, the trend analyses are complex, with disruption to the TOMS record due to the Mt. Pinatubo eruption (1991-93), and also a data gap (1994-96). Previous investigation in our department has shown systematic differences between comparable satellite measurements between 1996 and 1998. This poster presents results from an extended investigation into differences between total ozone measurements from TOVS, TOMS and GOME from 1996 to 2001. Such differences need to be quantified and understood in order to produce a reliable long-term record, and to provide a firm foundation that can be extended with data from new instruments such as SCIAMACHY, OMI and GOME-2, which so far will be the only instruments operating in the post-TOMS era. The new analyses over the 1996 2001 time period provide further evidence of regular systematic discrepancies of up to 30DU between co-located and concurrent measurements of total ozone from the three instruments. The increased time-series has permitted a more detailed study of the temporal periodicity and geographic patterns evident in the residuals. Specifically, effects due to clouds, topography, and albedo have been investigated, with initial results indicating a clear correlation between albedo and differences between measurements from all three instruments. Moreover, the effects instrument-specific problems encountered
Criteria equivalent to the Riemann Hypothesis
Cisło, J.; Wolf, M.
2008-11-01
We give a brief overview of a few criteria equivalent to the Riemann Hypothesis. Next we concentrate on the Riesz and Báez-Duarte criteria. We prove that they are equivalent and we provide some computer data to support them.
EQUIVALENT MODELS IN COVARIANCE STRUCTURE-ANALYSIS
LUIJBEN, TCW
1991-01-01
Defining equivalent models as those that reproduce the same set of covariance matrices, necessary and sufficient conditions are stated for the local equivalence of two expanded identified models M1 and M2 when fitting the more restricted model M0. Assuming several regularity conditions, the rank def
Galeazzi-equivalent lesions in adolescence.
Kamano, Masayuki; Honda, Yoshinobu
2002-07-01
Two cases of a Galeazzi-equivalent lesion in adolescence are described. Accurate diagnosis of the epiphyseal injury of the distal ulna, rigid fixation of the distal radius, and stabilization of the distal radioulnar joint are keys in obtaining a good result in the treatment of Galeazzi-equivalent lesion in adolescence.
Orientifold Planar Equivalence: The Chiral Condensate
DEFF Research Database (Denmark)
Armoni, Adi; Lucini, Biagio; Patella, Agostino
2008-01-01
The recently introduced orientifold planar equivalence is a promising tool for solving non-perturbative problems in QCD. One of the predictions of orientifold planar equivalence is that the chiral condensates of a theory with $N_f$ flavours of Dirac fermions in the symmetric (or antisymmetric...
Flow equivalence and isotopy for subshifts
DEFF Research Database (Denmark)
Boyle, Mike; Carlsen, Toke Meier; Eilers, Søren
2017-01-01
We study basic properties of flow equivalence on one-dimensional compact metric spaces with a particular emphasis on isotopy in the group of (self-) flow equivalences on such a space. In particular, we show that such an orbit-preserving map is not always an isotopy, but that this always is the ca...
The therapeutic equivalence of complex drugs
Schellekens, H.; Klinger, E.; Muehlebach, S.; Brin, J-F.; Storm, G.; Crommelin, D.J.A.
2011-01-01
When the patent of a small molecule drug expires generics may be introduced. They are considered therapeutically equivalent once pharmaceutical equivalence (i.e. identical active substances) and bioequivalence (i.e. comparable pharmacokinetics) have been established in a cross-over volunteer study.
A Discrete Equivalent of the Logistic Equation
Directory of Open Access Journals (Sweden)
Petropoulou EugeniaN
2010-01-01
Full Text Available A discrete equivalent and not analogue of the well-known logistic differential equation is proposed. This discrete equivalent logistic equation is of the Volterra convolution type, is obtained by use of a functional-analytic method, and is explicitly solved using the -transform method. The connection of the solution of the discrete equivalent logistic equation with the solution of the logistic differential equation is discussed. Also, some differences of the discrete equivalent logistic equation and the well-known discrete analogue of the logistic equation are mentioned. It is hoped that this discrete equivalent of the logistic equation could be a better choice for the modelling of various problems, where different versions of known discrete logistic equations are used until nowadays.
Calabi-Yau completions and orbifold equivalences
Carqueville, Nils
2015-01-01
Calabi-Yau algebras are particularly symmetric differential graded algebras. There is a construction due to Keller called `Calabi-Yau completion' which produces a canonical Calabi-Yau algebra from any homologically smooth dg algebra. Homologically smooth dg algebras also form a 2-category to which the construction of `equivariant completion' can be applied. In this theory two objects are called `orbifold equivalent' if there is a 1-morphism with invertible quantum dimensions between them. Any such relation entails a whole family of equivalences between categories. We show that Calabi-Yau completion and equivariant completion are compatible. More precisely, we prove that any orbifold equivalence between two homologically smooth and proper dg algebras lifts to an orbifold equivalence between their Calabi-Yau completions. As a corollary we obtain orbifold equivalences between Ginzburg algebras of Dynkin quivers.
Equivalence in Ventilation and Indoor Air Quality
Energy Technology Data Exchange (ETDEWEB)
Sherman, Max; Walker, Iain; Logue, Jennifer
2011-08-01
We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.
2012-10-05
... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent... methods for monitoring ambient air quality. SUMMARY: Notice is hereby given that the Environmental... in the ambient air. FOR FURTHER INFORMATION CONTACT: Robert Vanderpool, Human Exposure...
2013-11-12
... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of Five New Equivalent... of the designation of five new equivalent methods for monitoring ambient air quality. SUMMARY: Notice... measuring concentrations of PM 10-2.5 , two for measuring PM 2.5, and one for measuring NO 2 in the...
On Equivalence and Non-equivalence of Words and Phrases In Different Cultures
Institute of Scientific and Technical Information of China (English)
高新霞
2008-01-01
This paper is mainly focused on the study of the relationship among three concepts, namely, culture,psychological association and equivalence or non-equivalence of words and phrases with combination of Problems posed by my students and discuss three patterns of the relationship with an attempt to describe the importance of culture to equivalence.
Analytical and numerical construction of equivalent cables.
Lindsay, K A; Rosenberg, J R; Tucker, G
2003-08-01
The mathematical complexity experienced when applying cable theory to arbitrarily branched dendrites has lead to the development of a simple representation of any branched dendrite called the equivalent cable. The equivalent cable is an unbranched model of a dendrite and a one-to-one mapping of potentials and currents on the branched model to those on the unbranched model, and vice versa. The piecewise uniform cable, with a symmetrised tri-diagonal system matrix, is shown to represent the canonical form for an equivalent cable. Through a novel application of the Laplace transform it is demonstrated that an arbitrary branched model of a dendrite can be transformed to the canonical form of an equivalent cable. The characteristic properties of the equivalent cable are extracted from the matrix for the transformed branched model. The one-to-one mapping follows automatically from the construction of the equivalent cable. The equivalent cable is used to provide a new procedure for characterising the location of synaptic contacts on spinal interneurons.
Dinter, T.; Rozanov, V. V.; Burrows, J. P.; Bracher, A.
2015-01-01
The availability of light in the ocean is an important parameter for the determination of phytoplankton photosynthesis processes and primary production from satellite data. It is also a useful parameter for other applications, e.g. the determination of heat fluxes. In this study, a method was developed utilising the vibrational Raman scattering (VRS) effect of water molecules to determine the amount of photons available in the ocean water, which is expressed by the depth integrated scalar irradiance text-decoration:overline">E0. Radiative transfer simulations with the fully coupled ocean-atmosphere Radiative Transfer Model (RTM) SCIATRAN show clearly the relationship of text-decoration:overline">E0 to the strength of the VRS signal measured at the top of the atmosphere (TOA). Taking advantage of VRS structures in hyper-spectral satellite measurements a retrieval technique to derive text-decoration:overline"> E0 in the wavelength region from 390 to 444.5 nm was developed. This approach uses the Weighting Function Differential Optical Absorption Spectroscopy (WF-DOAS) technique, applied to TOA radiances, measured by the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY). Based on the approach of Vountas et al. (2007), where the DOAS method was used to fit modelled spectra of VRS, the method was improved by using the weighting function of VRS (VRS-WF) in the DOAS fit. This was combined with a look-up table (LUT) technique, where the text-decoration:overline"> E0 value was obtained for each VRS satellite fit directly. The VRS-WF and the LUT were derived from calculations with the RTM SCIATRAN (Rozanov et al., 2014). RTM simulations for different chlorophyll a concentrations and illumination conditions clearly show, that low fit factors of VRS retrieval results correspond to low amounts of light in the water column and vice versa. Exemplary, one month of SCIAMACHY data were processed and a global map of the depth integrated scalar
Analysis of affinely equivalent Boolean functions
Institute of Scientific and Technical Information of China (English)
MENG QingShu; ZHANG HuanGuo; YANG Min; WANG ZhangYi
2007-01-01
By some basic transforms and invariant theory, we give two results: 1) an algorithm,which can be used to judge if two Boolean functions are affinely equivalent and to obtain the equivalence relationship if they are equivalent. This is useful in studying Boolean functions and in engineering. For example, we classify all 8-variable homogeneous bent functions of degree 3 into two classes; 2) Reed-Muller codes R(4,6)/R(1,6), R(3,7)/R(1,7) are classified efficiently.
Antireflection design concepts with equivalent layers.
Schallenberg, Uwe B
2006-03-01
Some novel concepts of designing antireflection (AR) coatings with equivalent layers are presented. As an introduction, essential papers concerning thin-film optics and AR designs are cited, and the AR problem and a previously introduced AR-hard design type are discussed. Based on the known matrix formalism, a potential AR region, an equivalent stack index, and an equivalent substrate index are defined to use the theory of stop-band suppression as a starting point for the design of broadband AR coatings. The known multicycle AR design type is identified as a typical solution to the AR problem if the presented approach is used.
Institute of Scientific and Technical Information of China (English)
Chen Yu; Wen Yu-Mei; Li Ping
2006-01-01
The equivalent circuit with complex physical constants for a piezoelectric ceramic in thickness mode is established.In the equivalent circuit, electric components (equivalent circuit parameters) are connected to real and imaginary parts of complex physical coefficients of piezoelectric materials. Based on definitions of dissipation factors, three of them (dielectric, elastic and piezoelectric dissipation factors) are represented by equivalent circuit parameters. Since the equivalent circuit parameters are detectable, the dissipation factors can be easily obtained. In the experiments, the temperature and the stress responses of the three dissipation factors are measured.
Lexical Equivalence in Business English Translation
Institute of Scientific and Technical Information of China (English)
王淼
2009-01-01
Business English is English used in business contexts.It is a combination of knowledge in both business and language.Being faithful is of primary importance in business English translation,but a translation only faithful to the original is far from adequate if it is not appropriate to the original in style.Therefore,in doing business translation,the translators should always keep in mind the specific purposes and functions of the original texts and make attempts to render the closet natural equivalent in the target language.This article focuses on equivalence at lexical level in this chapter.Several major tendencies toward word choice are put forward and stylistic equivalence in each case is analyzed at some length.Three criteria are proposed here for choosing suitable words:preciseness,conciseness and gracefulness.If the three criteria are satisfied,stylistic equivalence will also be established.
Lexical Equivalence in Business English Translation
Institute of Scientific and Technical Information of China (English)
王淼
2009-01-01
Business English is English used in business contexts.It is a combination of knowledge in both business and language.Being faithful is ofprimary importance in business English Iranslation,but a translation only faithful to the original is far from adequate if it is not appropriate to the original in style.Therefore,in doing business translation,the translators should always keep in mind the specific purposes and functions ofthe original texts and make attempts to render the closet natural equivalent in the target language.This atticle focuses on equivalence at lexical level in this chapter.Several major tendencies toward word choice arc put forward and stylistic equivalence in each case is analyzed at some length.Three criteria are proposed here for choosing suitable words:preciseness,concise-ness and gracefulness.1fthe three criteria are satisfied,stylistic equivalence will also be established.
Equivalence Principle, Higgs Boson and Cosmology
Directory of Open Access Journals (Sweden)
Mauro Francaviglia
2013-05-01
Full Text Available We discuss here possible tests for Palatini f(R-theories together with their implications for different formulations of the Equivalence Principle. We shall show that Palatini f(R-theories obey the Weak Equivalence Principle and violate the Strong Equivalence Principle. The violations of the Strong Equivalence Principle vanish in vacuum (and purely electromagnetic solutions as well as on short time scales with respect to the age of the universe. However, we suggest that a framework based on Palatini f(R-theories is more general than standard General Relativity (GR and it sheds light on the interpretation of data and results in a way which is more model independent than standard GR itself.
Equivalence relations and the reinforcement contingency.
Sidman, M
2000-07-01
Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2-, 3-, 4-, 5-, or n-term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional discrimination, second-order conditional discrimination, and so on; and (b) equivalence relations that consist of ordered pairs of all positive elements that participate in the contingency. This conception of the origin of equivalence relations leads to a number of new and verifiable ways of conceptualizing equivalence relations and, more generally, the stimulus control of operant behavior. The theory is also capable of experimental disproof.
The effective theory of Borel equivalence relations
DEFF Research Database (Denmark)
Fokina, E.B.; Friedman, S.-D.; Törnquist, Asger Dag
2010-01-01
The study of Borel equivalence relations under Borel reducibility has developed into an important area of descriptive set theory. The dichotomies of Silver [20] and Harrington, Kechris and Louveau [6] show that with respect to Borel reducibility, any Borel equivalence relation strictly above...... under effectively Borel reducibility. The resulting structure is complex, even for equivalence relations with finitely many equivalence classes. However use of Kleene's O as a parameter is sufficient to restore the picture from the noneffective setting. A key lemma is that of the existence of two...... effectively Borel sets of reals, neither of which contains the range of the other under any effectively Borel function; the proof of this result applies Barwise compactness to a deep theorem of Harrington (see [5,16]) establishing for any recursive ordinal α the existence of Π singletons whose α...
Equivalent boundary integral equations for plane elasticity
Institute of Scientific and Technical Information of China (English)
胡海昌; 丁皓江; 何文军
1997-01-01
Indirect and direct boundary integral equations equivalent to the original boundary value problem of differential equation of plane elasticity are established rigorously. The unnecessity or deficiency of some customary boundary integral equations is indicated by examples and numerical comparison.
On the Notion of Equivalence in Translation
Institute of Scientific and Technical Information of China (English)
张颖
2016-01-01
Thanks to translations, varies cultures are allowed to exchange with one another. One the one hand, this has been promoting the studies of translation. On the other hand, this poses huge challenges on translators, because it is hard to define what is a good target translation when a source text is translated. There is a variety of standards to evaluate the quality of a translation, among which equivalence seems to be the most controversial one. On the analysis of studies on equivalence, this essay discusses the role of equivalence in the practice of translating with illustrations of Chinese-English and English-Chinese translation. Indeed, to translate a source text into a target one is based on the equivalence among languages. However, in the process of translating, it can be adjusted to some extent for the sake of the acceptability in the target culture.
interpratation: of equivalences and cultural untranslatability
African Journals Online (AJOL)
jgmweri
Interpretation: signs and meaning, diversity in language use, equivalences and ... movement of the hands, arms or body, and facial expressions to express ... people who belong to the same culture given the similar experiences they have gone.
ON THE EQUIVALENCE OF THE ABEL EQUATION
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
This article uses the reflecting function of Mironenko to study some complicated differential equations which are equivalent to the Abel equation. The results are applied to discuss the behavior of solutions of these complicated differential equations.
REFractions: The Representing Equivalent Fractions Game
Tucker, Stephen I.
2014-01-01
Stephen Tucker presents a fractions game that addresses a range of fraction concepts including equivalence and computation. The REFractions game also improves students' fluency with representing, comparing and adding fractions.
Equivalence relations and the reinforcement contingency.
Sidman, M
2000-01-01
Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2-, 3-, 4-, 5-, or n-term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional discrimination, second-order conditional discrimination, and so on; and (b) equivalence relations that consist of ordered pairs of all positive elements that...
Regional Differences in Equivalence Scales in Turkey
Directory of Open Access Journals (Sweden)
Gianni Betti
2017-03-01
Full Text Available Equivalence scales have a crucial role in poverty measurement. For Turkey, there are no available up-todate equivalence scales, representing Turkish data. There were no efforts for calculation of equivalence scales at the regional level. The aim of the paper is to calculate and propose an equivalence scale for Turkey and estimate regional differences. Besides the models with Engel method, different equivalence scales were estimated by Almost Ideal Demand System. The results of the first model of AIDS approach composed of 5 age groups, is proposed for Turkey, but for simplicity the results of the second AIDS model could be used as well. In this model, the equivalence scale for Turkey is calculated as 0.65 for each additional adult after the first one and 0.35 for each child. For regional equivalence scales, we use two methods and comare the results. In the first one, regressions were run for each region separately and in the second one, dummy variables introduced. The highest difference in the results of the two methods was observed in Istanbul region. The findings for the regional scales are less reliable as the household size is bigger. This limitation is due to the relatively small size of the data sets. Having surveys with higher sample sizes would enable better results. After getting the results some conclusions could be drawn especially with regard to child cost differences among regions. It was expected to have higher costs for children in poorer regions and the regional results have confirmed this hypothesis.
Zhang, Ping; Shu, Hua-lin; Yuan, Jin-bo; Shang, Juan-juan; Cui, Kai-feng; Chao, Si-jia; Wang, Shao-mao; Liu, Dao-xin; Huang, Xue-ren
2016-01-01
In this paper, blackbody radiation (BBR) temperature rise seen by the $^{40}$Ca$^+$ ion confined in a miniature Paul trap and its uncertainty have been evaluated via finite-element method (FEM) modelling. The FEM model was validated by comparing with thermal camera measurements, which were calibrated by PT1000 resistance thermometer, at several points on a dummy trap. The input modelling parameters were analyzed carefully in detail, and their contributions to the uncertainty of environment temperature were evaluated on the validated FEM model. The result shows that the temperature rise seen by $^{40}$Ca$^+$ ion is 1.72 K with an uncertainty of 0.46 K. It results in a contribution of 2.2 mHz to the systematic uncertainty of $^{40}$Ca$^+$ ion optical clock, corresponding to a fractional uncertainty 5.4$\\times$10$^{-18}$. This is much smaller than the uncertainty caused by the BBR shift coefficient, which is evaluated to be 4.8 mHz and at 10$^{-17}$ level in fractional frequency units.
Zhang, Ping; Cao, Jian; Shu, Hua-lin; Yuan, Jin-bo; Shang, Jun-juan; Cui, Kai-feng; Chao, Si-jia; Wang, Shao-mao; Liu, Dao-xin; Huang, Xue-ren
2017-01-01
In this paper, the blackbody radiation (BBR) temperature rise experienced by a 40Ca+ ion confined in a miniature Paul trap and its uncertainty have been evaluated via finite-element method (FEM) modelling. The FEM model was validated through comparisons with thermal camera measurements at several points on a dummy trap. Before the validation, the thermal camera was calibrated by using a PT1000 resistance thermometer. The input modelling parameters were analyzed carefully, and their contributions to the uncertainty of the trap environment temperature were evaluated using the validated FEM model. The result shows that the temperature rise experienced by the 40Ca+ ion is 1.72 K with an uncertainty of 0.46 K. It results in a contribution of 2.2 mHz to the systematic uncertainty of a 40Ca+ ion optical clock, corresponding to a fractional uncertainty 5.4 × 10-18. This is much smaller than the uncertainty caused by the BBR shift coefficient, which is evaluated to be 4.8 mHz and at the 10-17 level in fractional frequency units.
Koepferl, Christine M; Dale, James E
2016-01-01
We use a large data-set of realistic synthetic observations (PaperI) to assess how observational techniques affect the measurement of physical properties of star-forming regions. In this paper (PaperII), we explore the reliability of the measured total gas mass, dust surface density and dust temperature maps derived from modified blackbody fitting of synthetic Herschel observations. We found from our pixel-by-pixel analysis of the measured dust surface density and dust temperature a worrisome error spread especially close to star-formation sites and low-density regions, where for those "contaminated" pixels the surface densities can be under/overestimated by up to three orders of magnitude. In light of this, we recommend to treat the pixel-based results from this technique with caution in regions with active star formation. In regions of high background typical in the inner Galactic plane, we are not able to recover reliable surface density maps of individual synthetic regions, since low-mass regions are lost...
A Directional Dose Equivalent Monitor for Neutrons
Energy Technology Data Exchange (ETDEWEB)
D' Errico, F.; Alberts, W.G.; Curzio, G.; Matzke, M.; Nath, R.; Siebert, B.R.L
2001-07-01
A directional dose equivalent monitor is introduced which consists of a 30 cm diameter spherical phantom hosting a superheated drop detector embedded at a depth of 10 mm. The device relies on the similarity between the fluence response of neutron superheated drop detectors based on halocarbon-12 and the quality-factor-weighted kerma factor. This implies that these detectors can be used for in-phantom dosimetry and provide a direct reading of dose equivalent at depth. The directional dose equivalent monitor was characterised experimentally with fast neutron calibrations and numerically with Monte Carlo simulations. The fluence response was determined at angles of 0, 45, 90, 135 and 180 degrees for thermal to 20 MeV neutrons. The response of the device is closely proportional to the fluence-to-directional dose equivalent conversion coefficient, H'{sub F}(10;a,E). Therefore, our monitor is suitable for a direct measurement of neutron directional dose equivalent, H'(10), regardless of angle and energy distribution of the neutron fluence. (author)
System Equivalent for Real Time Digital Simulator
Lin, Xi
2011-07-01
The purpose of this research is to develop a method of making system equivalents for the Real Time Digital Simulator (RTDS), which should enhance its capability of simulating large power systems. The proposed equivalent combines a Frequency Dependent Network Equivalent (FDNE) for the high frequency electromagnetic transients and a Transient Stability Analysis (TSA) type simulation block for the electromechanical transients. The frequency dependent characteristic for FDNE is obtained by curve-fitting frequency domain admittance characteristics using the Vector Fitting method. An approach for approximating the frequency dependent characteristic of large power networks from readily available typical power-flow data is also introduced. A new scheme of incorporating TSA solution in RTDS is proposed. This report shows how the TSA algorithm can be adapted to a real time platform. The validity of this method is confirmed with examples, including the study of a multi in-feed HVDC system based network.
The New Wind Chill Equivalent Temperature Chart.
Osczevski, Randall; Bluestein, Maurice
2005-10-01
The formula used in the U.S. and Canada to express the combined effect of wind and low temperature on how cold it feels was changed in November 2001. Many had felt that the old formula for equivalent temperature, derived in the 1960s from Siple and Passel's flawed but quite useful Wind Chill Index, unnecessarily exaggerated the severity of the weather. The new formula is based on a mathematical model of heat flow from the upwind side of a head-sized cylinder moving at walking speed into the wind. The paper details the assumptions that were made in generating the new wind chill charts. It also points out weaknesses in the concept of wind chill equivalent temperature, including its steady-state character and a seemingly paradoxical effect of the internal thermal resistance of the cylinder on comfort and equivalent temperature. Some improvements and alternatives are suggested.
Fiscal adjustments in Europe and Ricardian equivalence
Directory of Open Access Journals (Sweden)
V. DE BONIS
1998-09-01
Full Text Available According to the ‘Ricardian’ equivalence hypothesis, consumption is dependent on permanent disposable income and current deficits are equivalent to future tax payments. This hypothesis is tested on 14 European countries in the 1990s. The relationships between private sector savings and general government deficit, and the GDP growth rate and the unemployment rate are determined. The results show the change in consumers' behaviour with respect to government deficit, and that expectations of an increase in future wealth are no longer associated with a decrease in deficit.
Equivalent circuit analysis of terahertz metamaterial filters
Zhang, Xueqian
2011-01-01
An equivalent circuit model for the analysis and design of terahertz (THz) metamaterial filters is presented. The proposed model, derived based on LMC equivalent circuits, takes into account the detailed geometrical parameters and the presence of a dielectric substrate with the existing analytic expressions for self-inductance, mutual inductance, and capacitance. The model is in good agreement with the experimental measurements and full-wave simulations. Exploiting the circuit model has made it possible to predict accurately the resonance frequency of the proposed structures and thus, quick and accurate process of designing THz device from artificial metamaterials is offered. ©2011 Chinese Optics Letters.
Algebraic cobordism theory attached to algebraic equivalence
Krishna, Amalendu
2012-01-01
After the algebraic cobordism theory of Levine-Morel, we develop a theory of algebraic cobordism modulo algebraic equivalence. We prove that this theory can reproduce Chow groups modulo algebraic equivalence and the zero-th semi-topological K-groups. We also show that with finite coefficients, this theory agrees with the algebraic cobordism theory. We compute our cobordism theory for some low dimensional or special types of varieties. The results on infinite generation of some Griffiths groups by Clemens and on smash-nilpotence by Voevodsky and Voisin are also lifted and reinterpreted in terms of this cobordism theory.
Atom interferometry and the Einstein equivalence principle
Wolf, Peter; Bordé, Christian J; Reynaud, Serge; Salomon, Christophe; Cohen-Tannoudji, Clande
2011-01-01
The computation of the phase shift in a symmetric atom interferometer in the presence of a gravitational field is reviewed. The difference of action-phase integrals between the two paths of the interferometer is zero for any Lagrangian which is at most quadratic in position and velocity. We emphasize that in a large class of theories of gravity the atom interferometer permits a test of the weak version of the equivalence principle (or universality of free fall) by comparing the acceleration of atoms with that of ordinary bodies, but is insensitive to that aspect of the equivalence principle known as the gravitational redshift or universality of clock rates.
A model for equivalent axle load factors
Amorim, Sara I.R.; Pais, Jorge; Vale, Aline C.; Minhoto, Manuel
2014-01-01
Most design methods for road pavements require the design traffic, based on the transformation of the traffic spectrum, to be calculated into a number of equivalent passages of a standard axle using the equivalent axle load factors. Generally, these factors only consider the type of axle (single, tandem or tridem), but they do not consider the type of wheel on the axles, i.e., single or dual wheel. The type of wheel has an important influence on the calculation of the design traffic. The exis...
Relative Derived Equivalences and Relative Homological Dimensions
Institute of Scientific and Technical Information of China (English)
Sheng Yong PAN
2016-01-01
Let A be a small abelian category. For a closed subbifunctor F of Ext1A (−,−), Buan has generalized the construction of Verdier’s quotient category to get a relative derived category, where he localized with respect to F-acyclic complexes. In this paper, the homological properties of relative derived categories are discussed, and the relation with derived categories is given. For Artin algebras, using relative derived categories, we give a relative version on derived equivalences induced by F-tilting complexes. We discuss the relationships between relative homological dimensions and relative derived equivalences.
AN EQUIVALENT CONTINUUM METHOD OF LATTICE STRUCTURES
Institute of Scientific and Technical Information of China (English)
Fan Hualin; Yang Wei
2006-01-01
An equivalent continuum method is developed to analyze the effective stiffness of three-dimensional stretching dominated lattice materials. The strength and three-dimensional plastic yield surfaces are calculated for the equivalent continuum. A yielding model is formulated and compared with the results of other models. The bedding-in effect is considered to include the compliance of the lattice joints. The predicted stiffness and strength are in good agreement with the experimental data, validating the present model in the prediction of the mechanical properties of stretching dominated lattice structures.
2012-09-11
... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of a New Equivalent Method... monitoring ambient air quality. SUMMARY: Notice is hereby given that the Environmental Protection Agency (EPA... concentrations of PM 2.5 in the ambient air. FOR FURTHER INFORMATION CONTACT: Robert Vanderpool, Human...
Experimental Uncertainties of TEPC Dose Equivalent
Institute of Scientific and Technical Information of China (English)
ZHANG; Wei-hua; XIAO; Xue-fu; WANG; Zhi-qiang; LIU; Yi-na; LI; Chun-juan; LUO; Hai-long
2013-01-01
The tissue-equivalent proportional counters(TEPC)are widely used for radiation protection in mixed radiation fields.The operational quantity H*(10)can be directly obtained by means of microdosimetric spectra measurements with TEPC.An empirical evaluation of uncertainties is reported in this paper.The sources of uncertainties involved in measuring microdosimetric spectra mainly are the sensitive
Reading adn Auditory-Visual Equivalences
Sidman, Murray
1971-01-01
A retarded boy, unable to read orally or with comprehension, was taught to match spoken to printed words and was then capable of reading comprehension (matching printed words to picture) and oral reading (naming printed words aloud), demonstrating that certain learned auditory-visual equivalences are sufficient prerequisites for reading…
Confluence Modulo Equivalence in Constraint Handling Rules
DEFF Research Database (Denmark)
Christiansen, Henning; Kirkeby, Maja Hanne
2014-01-01
Previous results on confluence for Constraint Handling Rules, CHR, are generalized to take into account user-defined state equivalence relations. This allows a much larger class of programs to enjoy the ad- vantages of confluence, which include various optimization techniques and simplified corre...
Equivalence of Conformal Superalgebras to Hamiltonian Superoperators
Institute of Scientific and Technical Information of China (English)
Xiaoping Xu
2001-01-01
In this paper, we present a formal variational calculus of super functions in one real variable and find the conditions for a "matrix differential operator'' to be a Hamiltonian superoperator. Moreover, we prove that conformal superalgebras are equivalent to certain Hamiltonian superoperators.
CP Violation, Neutral Currents, and Weak Equivalence
Fitch, V. L.
1972-03-23
Within the past few months two excellent summaries of the state of our knowledge of the weak interactions have been presented. Correspondingly, we will not attempt a comprehensive review but instead concentrate this discussion on the status of CP violation, the question of the neutral currents, and the weak equivalence principle.
On the Leitmann equivalent problem approach
F.O.O. Wagener
2009-01-01
The purpose of this paper is to show how Leitmann’s equivalent problem approach ties in with the classical notions of the calculus of variations and how it can be exploited to give a rapid and elegant approach to the Weierstrass theory of sufficient conditions. Fixed, free and constrained endpoint c
On Functional Equivalence of Idiom Translation
Institute of Scientific and Technical Information of China (English)
管琴
2008-01-01
The aim of this article is to discuss the feasibility of functional equivalence in idiom translations in Chinese-English cultures,trying to find efficient ways to avoid both under-translation and over-translation.The more functions are reproduced,the better the version will be at achieving correspondence between meaning and function.
Chameleonic equivalence postulate and wave function collapse
Zanzi, Andrea
2014-01-01
A chameleonic solution to the cosmological constant problem and the non-equivalence of different conformal frames at the quantum level have been recently suggested [Phys. Rev. D82 (2010) 044006]. In this article we further discuss the theoretical grounds of that model and we are led to a chameleonic equivalence postulate (CEP). Whenever a theory satisfies our CEP (and some other additional conditions), a density-dependence of the mass of matter fields is naturally present. Let us summarize the main results of this paper. 1) The CEP can be considered the microscopic counterpart of the Einstein's Equivalence Principle and, hence, a chameleonic description of quantum gravity is obtained: in our model, (quantum) gravitation is equivalent to a conformal anomaly. 2) To illustrate one of the possible applications of the CEP, we point out a connection between chameleon fields and quantum-mechanical wave function collapse. The collapse is induced by the chameleonic nature of the theory. We discuss the collapse for a S...
On the Equivalence of Regularization Schemes
Institute of Scientific and Technical Information of China (English)
YANG Ji-Feng
2002-01-01
We illustrate via the sunset diagram that dimensional regularization ‘deforms' the nonlocal contentsof multi-loop diagrams with its equivalence to cutoff regularization scheme recovered only after sub-divergence wassubtracted. Then we employed a differential equation approach for calculating loop diagrams to verify that dimensionalare argued especially in nonperturbativc perspective.
Equivalent thermal conductivity of heat pipes
Institute of Scientific and Technical Information of China (English)
Zesheng LU; Binghui MA
2008-01-01
In precision machining, the machining error from thermal distortion carries a high proportion of the total errors. If a precision machining tool can transfer heat fast, the thermal distortion will be reduced and the machining precision will be improved. A heat pipe working based on phase transitions of the inner working liquid transfers heat with high efficiency and is widely applied in spaceflight and chemical industries. In mechanics, applications of heat pipes are correspondingly less. When a heat pipe is applied to a hydrostatic motor-ized spindle, the thermal distortion cannot be solved dur-ing the heat transfer process because thermal conductivity or equivalent thermal conductivity should be provided first for special application in mechanics. An equivalent thermal conductivity model based on equivalent thermal resistances is established. Performance tests for a screen wick pipe, gravity pipe, and rotation heat pipe are done to validate the efficiency of the equivalent thermal conduc-tivity model. The proposed model provides a calculation method for the thermal distortion analysis of heat pipes applied in the motorized spindle.
Beyond Language Equivalence on Visibly Pushdown Automata
DEFF Research Database (Denmark)
Srba, Jiri
2009-01-01
We study (bi)simulation-like preorder/equivalence checking on the class of visibly pushdown automata and its natural subclasses visibly BPA (Basic Process Algebra) and visibly one-counter automata. We describe generic methods for proving complexity upper and lower bounds for a number of studied...
A Logical Characterisation of Static Equivalence
DEFF Research Database (Denmark)
Hüttel, Hans; Pedersen, Michael D.
2007-01-01
The work of Abadi and Fournet introduces the notion of a frame to describe the knowledge of the environment of a cryptographic protocol. Frames are lists of terms; two frames are indistinguishable under the notion of static equivalence if they satisfy the same equations on terms. We present a first...
THE EQUIVALENCE THEORY OF NATIVE SPACES
Institute of Scientific and Technical Information of China (English)
Lin-Tian Luh
2001-01-01
In this paper some equivalence definitions are given for native spaces which were introduced by Madych and Nelson and have become influential in the theory of radial basis functions. The abstract elements in na tive spaces are interpreted. Moreaver, Weinrich and Iske's theonies are unified.
Visual Equivalence and Amodal Completion in Cuttlefish.
Lin, I-Rong; Chiao, Chuan-Chin
2017-01-01
Modern cephalopods are notably the most intelligent invertebrates and this is accompanied by keen vision. Despite extensive studies investigating the visual systems of cephalopods, little is known about their visual perception and object recognition. In the present study, we investigated the visual processing of the cuttlefish Sepia pharaonis, including visual equivalence and amodal completion. Cuttlefish were trained to discriminate images of shrimp and fish using the operant conditioning paradigm. After cuttlefish reached the learning criteria, a series of discrimination tasks were conducted. In the visual equivalence experiment, several transformed versions of the training images, such as images reduced in size, images reduced in contrast, sketches of the images, the contours of the images, and silhouettes of the images, were used. In the amodal completion experiment, partially occluded views of the original images were used. The results showed that cuttlefish were able to treat the training images of reduced size and sketches as the visual equivalence. Cuttlefish were also capable of recognizing partially occluded versions of the training image. Furthermore, individual differences in performance suggest that some cuttlefish may be able to recognize objects when visual information was partly removed. These findings support the hypothesis that the visual perception of cuttlefish involves both visual equivalence and amodal completion. The results from this research also provide insights into the visual processing mechanisms used by cephalopods.
The Nature of Dynamic Equivalence in Translating
Nida, Eugene A.
1977-01-01
A discussion of three types of translation: formal correspondence, cognitive content and emotive response-oriented. The latter two are dynamic-equivalent translations. Their purpose is to enable the receptors to understand the implications of the cognitive content or to make a corresponding emotive response without recourse to the original text.…
An Equivalent Circuit for Landau Damping
DEFF Research Database (Denmark)
Pécseli, Hans
1976-01-01
An equivalent circuit simulating the effect of Landau damping in a stable plasma‐loaded parallel‐plate capacitor is presented. The circuit contains a double infinity of LC components. The transition from stable to unstable plasmas is simulated by the introduction of active elements into the circuit....
Canonical equivalence between massive spin 1 theories
Arias, P J; Arias, Pio J.; Perez-Mosquera, Jean C.
2004-01-01
The model of Cremmer-Scherck and Proca are considered in dimensions greater than 3+1. It is obtained that the Proca model correspond to a gauged fixed version of the Cremmer-Scherck one, and we show their canonical equivalence.
Visual Equivalence and Amodal Completion in Cuttlefish
Lin, I-Rong; Chiao, Chuan-Chin
2017-01-01
Modern cephalopods are notably the most intelligent invertebrates and this is accompanied by keen vision. Despite extensive studies investigating the visual systems of cephalopods, little is known about their visual perception and object recognition. In the present study, we investigated the visual processing of the cuttlefish Sepia pharaonis, including visual equivalence and amodal completion. Cuttlefish were trained to discriminate images of shrimp and fish using the operant conditioning paradigm. After cuttlefish reached the learning criteria, a series of discrimination tasks were conducted. In the visual equivalence experiment, several transformed versions of the training images, such as images reduced in size, images reduced in contrast, sketches of the images, the contours of the images, and silhouettes of the images, were used. In the amodal completion experiment, partially occluded views of the original images were used. The results showed that cuttlefish were able to treat the training images of reduced size and sketches as the visual equivalence. Cuttlefish were also capable of recognizing partially occluded versions of the training image. Furthermore, individual differences in performance suggest that some cuttlefish may be able to recognize objects when visual information was partly removed. These findings support the hypothesis that the visual perception of cuttlefish involves both visual equivalence and amodal completion. The results from this research also provide insights into the visual processing mechanisms used by cephalopods. PMID:28220075
Angular Momentum Eigenstates for Equivalent Electrons.
Tuttle, E. R.; Calvert, J. B.
1981-01-01
Simple and efficient methods for adding angular momenta and for finding angular momentum eigenstates for systems of equivalent electrons are developed. Several different common representations are used in specific examples. The material is suitable for a graduate course in quantum mechanics. (SK)
Fuel Cell Equivalent Electric Circuit Parameter Mapping
DEFF Research Database (Denmark)
Jeppesen, Christian; Zhou, Fan; Andreasen, Søren Juhl
In this work a simple model for a fuel cell is investigated for diagnostic purpose. The fuel cell is characterized, with respect to the electrical impedance of the fuel cell at non-faulty conditions and under variations in load current. Based on this the equivalent electrical circuit parameters c...
The equivalence principle in a quantum world
DEFF Research Database (Denmark)
Bjerrum-Bohr, N. Emil J.; Donoghue, John F.; El-Menoufi, Basem Kamal
2015-01-01
We show how modern methods can be applied to quantum gravity at low energy. We test how quantum corrections challenge the classical framework behind the equivalence principle (EP), for instance through introduction of nonlocality from quantum physics, embodied in the uncertainty principle. When t...... (EFT)....
A quality index for equivalent uniform dose
Henríquez, Francisco Cutanda; Castrillón, Silvia Vargas
2011-01-01
Equivalent uniform dose (EUD) is the absorbed dose that, when homogeneously given to a tumor, yields the same mean surviving clonogen number as the given non-homogeneous irradiation. EUD is used as an evaluation tool under the assumption that two plans with the same value of EUD are equivalent, and their biological effect on the tumor (clonogen survival) would be the same as the one of a homogeneous irradiation of absorbed dose EUD. In this work, this assumption has been studied, and a figure of merit of its applicability has been obtained. Distributions of surviving clonogen number for homogeneous and non-homogeneous irradiations are found to be different even if their mean values are the same, the figure of merit being greater when there is a wider difference, and the equivalence assumption being less valid. Therefore, EUD can be closer to a uniform dose for some cases than for other ones (high α values, extreme heterogeneity), and the accuracy of the radiobiological indices obtained for evaluation, could be affected. Results show that the equivalence is very sensitive to the choice of radiobiological parameters, and this conclusion has been derived from mathematical properties of EUD. PMID:21897557
Directory of Open Access Journals (Sweden)
F. Spada
2006-02-01
Full Text Available A new multiple-scattering Monte Carlo 3-D radiative transfer model named McSCIA (Monte Carlo for SCIAmachy is presented. The backward technique is used to efficiently simulate narrow field of view instruments. The McSCIA algorithm has been formulated as a function of the Earth's radius, and can thus perform simulations for both plane-parallel and spherical atmospheres. The latter geometry is essential for the interpretation of limb satellite measurements, as performed by SCIAMACHY on board of ESA's Envisat. The model can simulate UV-vis-NIR radiation.
First the ray-tracing algorithm is presented in detail, and then successfully validated against literature references, both in plane-parallel and in spherical geometry. A simple 1-D model is used to explain two different ways of treating absorption. One method uses the single scattering albedo while the other uses the equivalence theorem. The equivalence theorem is based on a separation of absorption and scattering. It is shown that both methods give, in a statistical way, identical results for a wide variety of scenarios. Both absorption methods are included in McSCIA, and it is shown that also for a 3-D case both formulations give identical results. McSCIA limb profiles for atmospheres with and without absorption compare well with the one of the state of the art Monte Carlo radiative transfer model MCC++.
A simplification of the photon statistics may lead to very fast calculations of absorption features in the atmosphere. However, these simplifications potentially introduce biases in the results. McSCIA does not use simplifications and is therefore a relatively slow implementation of the equivalence theorem. For the first time, however, the validity of the equivalence theorem is demonstrated in a spherical 3-D radiative transfer model.
Representing Identity and Equivalence for Scientific Data
Wickett, K. M.; Sacchi, S.; Dubin, D.; Renear, A. H.
2012-12-01
Matters of equivalence and identity are central to the stewardship of scientific data. In order to properly prepare for and manage the curation, preservation and sharing of digitally-encoded data, data stewards must be able to characterize and assess the relationships holding between data-carrying digital resources. However, identity-related questions about resources and their information content may not be straightforward to answer: for example, what exactly does it mean to say that two files contain the same data, but in different formats? Information content is frequently distinguished from particular representations, but there is no adequately developed shared understanding of what this really means and how the relationship between content and its representations hold. The Data Concepts group at the Center for Informatics Research in Science and Scholarship (CIRSS), University of Illinois at Urbana Champaign, is developing a logic-based framework of fundamental concepts related to scientific data to support curation and integration. One project goal is to develop precise accounts of information resources carrying the same data. We present two complementary conceptual models for information representation: the Basic Representation Model (BRM) and the Systematic Assertion Model (SAM). We show how these models provide an analytical account of digitally-encoded scientific data and a precise understanding of identity and equivalence. The Basic Representation Model identifies the core entities and relationships involved in representing information carried by digital objects. In BRM, digital objects are symbol structures that express propositional content, and stand in layered encoding relationships. For example, an RDF description may be serialized as either XML or N3, and those expressions in turn may be encoded as either UTF-8 or UTF-16 sequences. Defining this encoding stack reveals distinctions necessary for a precise account of identity and equivalence
Equivalent dynamic model of DEMES rotary joint
Zhao, Jianwen; Wang, Shu; Xing, Zhiguang; McCoul, David; Niu, Junyang; Huang, Bo; Liu, Liwu; Leng, Jinsong
2016-07-01
The dielectric elastomer minimum energy structure (DEMES) can realize large angular deformations by a small voltage-induced strain of the dielectric elastomer (DE), so it is a suitable candidate to make a rotary joint for a soft robot. Dynamic analysis is necessary for some applications, but the dynamic response of DEMESs is difficult to model because of the complicated morphology and viscoelasticity of the DE film. In this paper, a method composed of theoretical analysis and experimental measurement is presented to model the dynamic response of a DEMES rotary joint under an alternating voltage. Based on measurements of equivalent driving force and damping of the DEMES, the model can be derived. Some experiments were carried out to validate the equivalent dynamic model. The maximum angle error between model and experiment is greater than ten degrees, but it is acceptable to predict angular velocity of the DEMES, therefore, it can be applied in feedforward-feedback compound control.
Developing equivalent circuits for radial distribution networks
Energy Technology Data Exchange (ETDEWEB)
Prada, Ricardo; Coelho, Agnelo; Rodrigues, Anselmo [Catholic University of Rio de Janeiro (PUC-Rio), RJ (Brazil). Dept. of Electrical Engineering], Emails: prada@ele.puc-rio.br, agnelo@ele.puc-rio.br, nebulok_99@yahoo.com; Silva, Maria da Guia da [Federal University of Maranhao, Sao Luiz, MA (Brazil). Dept. of Electrical Engineering
2009-07-01
This paper presents a method for evaluating External Equivalent in Electric Distribution Networks (EDN).The proposed method has as its main objectives the reduction of the computational costs in distribution network reconfiguration, investigation of the optimal allocation of banks of capacitors, investigation of the allocation of distributed generation, etc. In these sorts of problems a large number of alternative projects must be assessed in order to identify the optimal solution. The optimal solution comes up with the voltage level in the load points within specified limits. Consequently, the EDN must retain the external network load points but without major increasing in the dimension of the equivalent circuit. The proposed method has been tested and validated in a substation of the Electricity Utility of Maranhao - CEMAR, in Brazil. (author)
On the equivalence of GPD representations
Müller, Dieter; Semenov-Tian-Shansky, Kirill
2016-10-01
Phenomenological representations of generalized parton distributions (GPDs) implementing the non-trivial field theoretical requirements are employed in the present day strategies for extracting of hadron structure information encoded in GPDs from the observables of hard exclusive reactions. Showing out the equivalence of various GPD representations can help to get more insight into GPD properties and allow to build up flexible GPD models capable of satisfactory description of the whole set of available experimental data. Below we review the mathematical aspects of establishing equivalence between the the double partial wave expansion of GPDs in the conformal partial waves and in the t-channel SO(3) partial waves and the double distribution representation of GPDs
Testing the Equivalence of Regular Languages
Directory of Open Access Journals (Sweden)
Marco Almeida
2009-07-01
Full Text Available The minimal deterministic finite automaton is generally used to determine regular languages equality. Antimirov and Mosses proposed a rewrite system for deciding regular expressions equivalence of which Almeida et al. presented an improved variant. Hopcroft and Karp proposed an almost linear algorithm for testing the equivalence of two deterministic finite automata that avoids minimisation. In this paper we improve the best-case running time, present an extension of this algorithm to non-deterministic finite automata, and establish a relationship between this algorithm and the one proposed in Almeida et al. We also present some experimental comparative results. All these algorithms are closely related with the recent coalgebraic approach to automata proposed by Rutten.
Galilean Equivalence for Galactic Dark Matter
Kesden, M; Kesden, Michael; Kamionkowski, Marc
2006-01-01
Satellite galaxies of the Milky Way experience a tidal disruption as they orbit in the Milky Way's dark halo. While the bound core of the satellite remains dominated by dark matter, the tidally disrupted stars behave like purely baryonic tracers of the Milky Way's potential well. If dark matter experiences a stronger self attraction than visible matter, stars will preferentially gain rather than lose energy during tidal disruption. This leads to a relative enhancement in the trailing as compared to the leading tidal stream. We show that the absence of a strong asymmetry in the surface brightness of the leading and trailing tidal streams already constrains the equivalence of acceleration of dark matter and baryons in a gravitational field to less than ten percent--thus ruling out a recently proposed mechanism to clear dwarf galaxies from voids. Future observations should be sensitive at the percent level to departures from the equivalence of dark matter and baryons.
Underlining some aspects of the equivalence principle
Benedetto, E.; Feoli, A.
2017-09-01
We want to shed light on some discussed aspects of the principle of equivalence. We consider two different phases in the evolution of the principle. We pay attention to the fact that some textbooks do not dwell on the mathematical meaning of ‘locally flat spacetime’, which can confuse students and, occasionally, can also lead to misinterpretations. For example, the non-eliminability of tidal forces, not even locally, may suggest that the equivalence principle is wrong. By contrast, we want to show that this is in perfect agreement with the Einstein geometrical interpretation of spacetime. Finally, in order to check the approximations used in the Gedankenexperiment of an elevator, we estimate explicitly the magnitude of the deflection of light and the effects of tidal forces in a ‘real lift’.
On the equivalence of GPD representations
Müller, Dieter
2016-01-01
Phenomenological representations of generalized parton distributions (GPDs) implementing the non-trivial field theoretical requirements are employed in the present day strategies for extracting of hadron structure information encoded in GPDs from the observables of hard exclusive reactions. Showing out the equivalence of various GPD representations can help to get more insight into GPD properties and allow to build up flexible GPD models capable of satisfactory description of the whole set of available experimental data. We review the mathematical aspects of establishing equivalence between the the double partial wave expansion of GPDs in the conformal partial waves and in the $t$-channel ${\\rm SO}(3)$ partial waves and the double distribution representation of GPDs.
Probing Quantum Violations of the Equivalence Principle
Adunas, G Z; Ahluwalia, D V
2001-01-01
The joint realm of quantum mechanics and the general-relativistic description of gravitation is becoming increasingly accessible to terrestrial experiments and observations. In this essay we study the emerging indications of the violation of equivalence principle (VEP). While the solar neutrino anomaly may find its natural explanation in a VEP, the statistically significant discrepancy observed in the gravitationally induced phases of neutron interferometry seems to be the first indication of a VEP. However, such a view would seem immediately challenged by the atomic interferometry results. The latter experiments see no indications of VEP, in apparent contradiction to the neutron interferometry results. Here we present arguments that support the view that these, and related torsion pendulum experiments, probe different aspects of gravity; and that current experimental techniques, when coupled to the solar-neutrino data, may be able to explore quantum mechanically induced violations of the equivalence principl...
Orientifold Planar Equivalence: The Quenched Meson Spectrum
Lucini, Biagio; Patella, Agostino; Rago, Antonio
2010-01-01
A numerical study of Orientifold Planar Equivalence is performed in SU(N) Yang-Mills theories for N=2,3,4,6. Quenched meson masses are extracted in the antisymmetric, symmetric and adjoint representations for the pseudoscalar and vector channels. An extrapolation of the vector mass as a function of the pseudoscalar mass to the large-N limit shows that the numerical results agree within errors for the three theories, as predicted by Orientifold Planar Equivalence. As a byproduct of the extrapolation, the size of the corrections up to O(1/N^3) are evaluated. A crucial prerequisite for the extrapolation is the determination of an analytical relationship between the corrections in the symmetric and in the antisymmetric representations, order by order in a 1/N expansion.
A Cutoff for Blackbody Radiation
Cahill, M.
2000-05-01
An analysis of the statistical mechanics of spherical star clusters and the simpler case of monatomic ideal gases is known to reveal that the Michie-King globular cluster energy cutoff can be written as \\varepsilonc ln ( N ) /line\\varepsilon where \\varepsilonc is the cutoff energy, /line=\\varepsilon is the average energy, the masses are assumed identical and where the number of cluster stars or gas particles, N, is large. The statistical methods leading to this result are shown to work for a photon gas. The usual method of dividing phase space into cells each with Λ quantum compartments to which Bose-Einstein statistics apply is used. The resulting distribution law is D (Λ -1+Λ ρ ) -D ( Λ ρ ) =\\varepsilon/ \\varepsilono where D is the logarithmic derivative of the factorial function, \\varepsilon and \\varepsilon o are respectively the energy variable and an energy constant characterising the distribution and where ρ is the quantum compartment particle number density ρ =h3dn/dω , with\\ dω being the phase space volume element. The distributions ρ ( \\varepsilon /\\varrepsilono, Λ ) are shown to be a one parameter family of distributions which approach the Planck law as Λ approaches ∞ . For large Λ , the photon density falls to 0, where it is cut off, at \\varepsilon = \\varepsilonc ln ( Λ ) /line\\varrepsilon. If the energy of a photon gas is finite, there must be a frequency cutoff since photon energy is proportional to frequency. It follows that Λ is finite, it is shown that Λ N, and that the Planck law is an excellent approximation for its distribution except in the tail region. Also the last 2 equations imply equation 1 holds for the photon gas.
Electromagnetic Boundaries with PEC/PMC Equivalence
Lindell, Ismo V
2016-01-01
The most general electromagnetic boundary, defined by linear and local boundary conditions, is defined in terms of conditions which can be called generalized impedance boundary conditions. Requiring that the boundary be equivalent to PEC and PMC boundaries for its two eigen-plane waves, which property is known to exist for many of its special cases, it is shown that the recently introduced Generalized Soft-and-Hard/DB (GSHDB) boundary is the most general boundary satisfying this property.
Capacitors with low equivalent series resistance
Fleig, Patrick Franz (Inventor); Lakeman, Charles D. E. (Inventor); Fuge, Mark (Inventor)
2011-01-01
An electric double layer capacitor (EDLC) in a coin or button cell configuration having low equivalent series resistance (ESR). The capacitor comprises mesh or other porous metal that is attached via conducting adhesive to one or both the current collectors. The mesh is embedded into the surface of the adjacent electrode, thereby reducing the interfacial resistance between the electrode and the current collector, thus reducing the ESR of the capacitor.
Quantum mechanics from an equivalence principle
Energy Technology Data Exchange (ETDEWEB)
Faraggi, A.E. [Univ. of Florida, Gainesville, FL (United States). Inst. for Fundamental Theory; Matone, M. [Univ. of Padova (Italy)
1997-05-15
The authors show that requiring diffeomorphic equivalence for one-dimensional stationary states implies that the reduced action S{sub 0} satisfies the quantum Hamilton-Jacobi equation with the Planck constant playing the role of a covariantizing parameter. The construction shows the existence of a fundamental initial condition which is strictly related to the Moebius symmetry of the Legendre transform and to its involutive character. The universal nature of the initial condition implies the Schroedinger equation in any dimension.
Translation Theory and the Problem of Equivalence
García-Landa, Mariano
2000-01-01
El presente artículo se ocupa de estudiar el problema de la equivalencia desde la perspectiva de la teoría de la traducción, y las posibles soluciones que puede dársele a esta cuestión This article is devoted to the study of the problem of equivalence in translation theory, and to the different possibilities available to find a solution
Residential Building Envelope Alternatives with Equivalent Cost
2011-01-01
Selecting the optimum envelope alternative in buildings is one of the most important factors in ensuring thermal comfort. This study calculated the heating costs, construction and lifecycle costs for a residential building in Istanbul with different envelope alternatives created by changing the type and thickness of the body and insulation materials used in the walls and roof, which are the structural components forming the building envelope. Envelope alternatives with equivalent costs were d...
Equivalent Lagrangians: Generalization, Transformation Maps, and Applications
Directory of Open Access Journals (Sweden)
N. Wilson
2012-01-01
Full Text Available Equivalent Lagrangians are used to find, via transformations, solutions and conservation laws of a given differential equation by exploiting the possible existence of an isomorphic algebra of Lie point symmetries and, more particularly, an isomorphic Noether point symmetry algebra. Applications include ordinary differential equations such as the Kummer equation and the combined gravity-inertial-Rossbywave equation and certain classes of partial differential equations related to multidimensional wave equations.
Adaptive passive equivalence of uncertain Lü system
Institute of Scientific and Technical Information of China (English)
Qi Dong-Lian
2006-01-01
An adaptive passive strategy for controlling uncertain Lü system is proposed. Since the uncertain Lü system is minimum phase and the uncertain parameters are from a bounded compact set, the essential conditions are studied by which uncertain Lü system could be equivalent to a passive system, and the adaptive control law is given. Using passive theory, the uncertain Lü system could be globally asymptotically stabilized at different equilibria by the smooth state feedback.
On the equivalence theorem for integrable systems
Melikyan, A; Rivelles, V O
2014-01-01
We investigate the equivalence theorem for integrable systems using two formulations of the Alday-Arutyunov-Frolov model. We show that the S-matrix is invariant under the field transformation which reduces the non-linear Dirac brackets of one formulation into the standard commutation relations in the second formulation. We also explain how to perform the direct diagonalization of the transformed Hamiltonian by constructing the states corresponding to self-adjoint extensions.
Cyclic and Inductive Calculi are equivalent
Voicu, Razvan
2011-01-01
Brotherston and Simpson [citation] have formalized and investigated cyclic reasoning, reaching the important conclusion that it is at least as powerful as inductive reasoning (specifically, they showed that each inductive proof can be translated into a cyclic proof). We add to their investigation by proving the converse of this result, namely that each inductive proof can be translated into an inductive one. This, in effect, establishes the equivalence between first order cyclic and inductive calculi.
Cyclic and Inductive Calculi are equivalent
Razvan VOICU; Li, Mengran
2011-01-01
Brotherston and Simpson [citation] have formalized and investigated cyclic reasoning, reaching the important conclusion that it is at least as powerful as inductive reasoning (specifically, they showed that each inductive proof can be translated into a cyclic proof). We add to their investigation by proving the converse of this result, namely that each inductive proof can be translated into an inductive one. This, in effect, establishes the equivalence between first order cyclic and inductive...
The Otto-engine-equivalent vehicle concept
Dowdy, M. W.; Couch, M. D.
1978-01-01
A vehicle comparison methodology based on the Otto-Engine Equivalent (OEE) vehicle concept is described. As an illustration of this methodology, the concept is used to make projections of the fuel economy potential of passenger cars using various alternative power systems. Sensitivities of OEE vehicle results to assumptions made in the calculational procedure are discussed. Factors considered include engine torque boundary, rear axle ratio, performance criteria, engine transient response, and transmission shift logic.
Equivalency of two-dimensional algebras
Energy Technology Data Exchange (ETDEWEB)
Santos, Gildemar Carneiro dos; Pomponet Filho, Balbino Jose S. [Universidade Federal da Bahia (UFBA), BA (Brazil). Inst. de Fisica
2011-07-01
Full text: Let us consider a vector z = xi + yj over the field of real numbers, whose basis (i,j) satisfy a given algebra. Any property of this algebra will be reflected in any function of z, so we can state that the knowledge of the properties of an algebra leads to more general conclusions than the knowledge of the properties of a function. However structural properties of an algebra do not change when this algebra suffers a linear transformation, though the structural constants defining this algebra do change. We say that two algebras are equivalent to each other whenever they are related by a linear transformation. In this case, we have found that some relations between the structural constants are sufficient to recognize whether or not an algebra is equivalent to another. In spite that the basis transform linearly, the structural constants change like a third order tensor, but some combinations of these tensors result in a linear transformation, allowing to write the entries of the transformation matrix as function of the structural constants. Eventually, a systematic way to find the transformation matrix between these equivalent algebras is obtained. In this sense, we have performed the thorough classification of associative commutative two-dimensional algebras, and find that even non-division algebra may be helpful in solving non-linear dynamic systems. The Mandelbrot set was used to have a pictorial view of each algebra, since equivalent algebras result in the same pattern. Presently we have succeeded in classifying some non-associative two-dimensional algebras, a task more difficult than for associative one. (author)
TNT equivalency of M10 propellant
Mcintyre, F. L.; Price, P.
1978-01-01
Peak, side-on blast overpressure and scaled, positive impulse have been measured for M10 single-perforated propellant, web size 0.018 inches, using configurations that simulate the handling of bulk material during processing and shipment. Quantities of 11.34, 22.7, 45.4, and 65.8 kg were tested in orthorhombic shipping containers and fiberboard boxes. High explosive equivalency values for each test series were obtained as a function of scaled distance by comparison to known pressure, arrival time and impulse characteristics for hemispherical TNT surface bursts. The equivalencies were found to depend significantly on scaled distance, with higher values of 150-100 percent (pressure) and 350-125 percent (positive impulse) for the extremes within the range from 1.19 to 3.57 m/cube root of kg. Equivalencies as low as 60-140 percent (pressure) and 30-75 percent (positive impulse) were obtained in the range of 7.14 to 15.8 m/cube root of kg. Within experimental error, both peak pressure and positive impulse scaled as a function of charge weight for all quantities tested in the orthorhombic configuration.
Measurement equivalence in mixed mode surveys
Directory of Open Access Journals (Sweden)
Joop J. Hox
2015-02-01
Full Text Available Surveys increasingly use mixed mode data collection (e.g., combining face-to-face and web because this controls costs and helps to maintain good response rates. However, a combination of different survey modes in one study, be it cross-sectional or longitudinal, can lead to different kinds of measurement errors. For example, respondents in a face-to-face survey or a web survey may interpret the same question differently, and might give a different answer, just because of the way the question is presented. This effect of survey mode on the question-answer process is called measurement mode effect. This study develops methodological and statistical tools to identify the existence and size of mode effects in a mixed mode survey. In addition, it assesses the size and importance of mode effects in measurement instruments using a specific mixed mode panel survey (Netherlands Kinship Panel Study. Most measurement instruments in the NKPS are multi-item scales, therefore confirmatory factor analysis (CFA will be used as the main analysis tool, using propensity score methods to correct for selection effects.The results show that the NKPS scales by and large have measurement equivalence, but in most cases only partial measurement equivalence. Controlling for respondent differences on demographic variables, and on scale scores from the previous uni-mode measurement occasion, tends to improve measurement equivalence, but not for all scales. The discussion ends with a review of the implications of our results for analyses employing these scales.
Orientifold Planar Equivalence: The Chiral Condensate
Armoni, A; Patella, A; Pica, C
2008-01-01
The recently introduced orientifold planar equivalence is a promising tool for solving non-perturbative problems in QCD. One of the predictions of orientifold planar equivalence is that the chiral condensates of a theory with $N_f$ flavours of Dirac fermions in the symmetric (or antisymmetric) representation and $N_f$ flavours of Majorana fermions in the adjoint representation have the same large $N$ value for any value of the mass of the (degenerate) fermions. Assuming the invariance of the theory under charge conjugation, we prove this statement on the lattice for staggered quenched condensates in SU($N$) Yang-Mills in the large $N$ limit. Then, we compute numerically those quenched condensates for $N$ up to 8. After separating the even from the odd corrections in $1/N$, we are able to show that our data support the equivalence; however, unlike other quenched observables, subleading terms in $1/N$ are needed for describing the data for the symmetric and antisymmetric representation at $N$=3. Possible lesson...
Homeomorphisms, homotopy equivalences and chain complexes
Adams-Florou, Spiros
2012-01-01
This thesis concerns the relationship between bounded and controlled topology and how these can be used to recognise which homotopy equivalences of reasonable topological spaces are homotopic to homeomorphisms. Let $f:X\\to Y$ be a simplicial map of finite-dimensional locally finite simplicial complexes. We prove that $f$ has contractible point inverses if and only if it is an $\\epsilon$-controlled homotopy equivalences for all $\\epsilon>0$, if and only if $f\\times\\mathrm{id}:X\\times\\mathbb{R} \\to Y\\times\\mathbb{R}$ is a homotopy equivalence bounded over the open cone $O(Y^+)$ of Pedersen and Weibel. This approach can be generalised to algebra using geometric categories: the $X$-controlled categories $\\mathbb{A}^*(X)$, $\\mathbb{A}_*(X)$ of Ranicki and Weiss together with the bounded categories $\\mathcal{C}_M(\\mathbb{A})$ of Pedersen and Weibel. Analogous to the barycentric subdivision of a simplicial complex, we define the algebraic subdivision of a chain complex over that simplicial complex. The main theorem ...
Approximate trace and singleton failures equivalences for transition systems
Institute of Scientific and Technical Information of China (English)
Chao Wang; Jinzhao Wu; Hongyan Tan
2015-01-01
Established system equivalences for transition systems, such as trace equivalence and failures equivalence, require the ob-servations to be exactly identical. However, an accurate measure-ment is impossible when interacting with the physical world, hence exact equivalence is restrictive and not robust. Using Baire met-ric, a generalized framework of transition system approximation is proposed by developing the notions of approximate language equivalence and approximate singleton failures (SF) equivalence. The framework takes the traditional exact equivalence as a special case. The approximate language equivalence is coarser than the approximate SF equivalence, just like the hierarchy of the exact ones. The main conclusion is that the two approximate equiva-lences satisfy the transitive property, consequently, they can be successively used in transition system approximation.
Electrical equivalent model of intermediate band solar cell using PSpice
Indian Academy of Sciences (India)
B Lakehal; Z Dibi; N Lakhdar; A Dendouga
2015-08-01
Intermediate band solar cells (IBSCS) is a relatively new solar cell concept. The theoretical conversion efficiency limit for IBSCS is predicted to be 63.2% with blackbody illumination and 65.1% with AM1.5 spectrum, comparable to the theoretical efficiency for optimized triple junction solar cells with efficiencies of 63.8% and 67.0% under blackbody and AM1.5 illumination, respectively. This paper presents a structure of IBSC based on ZnTe:O. The proposed model uses irradiance and temperature as input parameters and the output characteristics of the structure are used as a prototypical example. So, in this work the artificial neural networks (ANNs) and the analog behavior modeling (ABM) of PSpice are implemented in order to model the IBSC. In addition, we have used the bias matrix and the weights matrix obtained by training to establish the IBSCS model on PSPICE simulator. This method represents an advantage by using a small representative database. Therefore, the obtained results of our model can be used in an electrical simulator. Thus, this method can be extended to other solar cells for motivating experimental efforts to realize these promising photovoltaic devices for low cost and high efficiency.
Kunze, Kerstin E.; Komatsu, Eiichiro
2014-01-01
Primordial magnetic fields that exist before the photon-baryon decoupling epoch are damped on length scales below the photon diffusion and free-streaming scales. The energy injected into the plasma by dissipation of magnetosonic and Alfv&aposen waves heats photons, creating a y-type distortion of the black-body spectrum of the cosmic microwave background. This y-type distortion is converted into a μ-type distortion when elastic Compton scattering is efficient. Therefore, we can use observational limits on y- and μ-type distortions to constrain properties of magnetic fields in the early universe. Assuming a Gaussian, random, and non-helical field, we calculate μ and y as a function of the present-day strength of the field, B0, smoothed over a certain Gaussian width, kc-1, as well as of the spectral index of the power spectrum of fields, nB, defined by PB(k)proptoknB. For a nearly scale-invariant spectrum with nB = -2.9 and a Gaussian smoothing width of kc-1 = 1Mpc, the existing COBE/FIRAS limit on μ yields B0 FIRAS limit on μ excludes a wide range of spectral indices given by nB > -2.6. After decoupling, energy dissipation is due to ambipolar diffusion and decaying MHD turbulence, creating a y-type distortion. The distortion is completely dominated by decaying MHD turbulence, and is of order y ≈ 10-7 for a few nG field smoothed over the damping scale at the decoupling epoch, kd, dec ≈ 290(B0/1nG)-1Mpc-1. The projected PIXIE limit on y would exclude B0 > 1.0 and 0.6 nG for nB = -2.9 and -2.3, respectively, and B0 > 0.6 nG for nB >= 2. Finally, we find that the current limits on the optical depth to Thomson scattering restrict the predicted y-type distortion to be ylesssim10-8.
Directory of Open Access Journals (Sweden)
F. Spada
2006-01-01
Full Text Available A new multiple-scattering Monte Carlo 3-D radiative transfer model named McSCIA (Monte Carlo for SCIAmachy is presented. The backward technique is used to efficiently simulate narrow field of view instruments. The McSCIA algorithm has been formulated as a function of the Earth's radius, and can thus perform simulations for both plane-parallel and spherical atmospheres. The latter geometry is essential for the interpretation of limb satellite measurements, as performed by SCIAMACHY on board of ESA's Envisat. The model can simulate UV-vis-NIR radiation. First the ray-tracing algorithm is presented in detail, and then successfully validated against literature references, both in plane-parallel and in spherical geometry. A simple 1-D model is used to explain two different ways of treating absorption. One method uses the single scattering albedo while the other uses the equivalence theorem. The equivalence theorem is based on a separation of absorption and scattering. It is shown that both methods give, in a statistical way, identical results for a wide variety of scenarios. Both absorption methods are included in McSCIA, and it is shown that also for a 3-D case both formulations give identical results. McSCIA limb profiles for atmospheres with and without absorption compare well with the one of the state of the art Monte Carlo radiative transfer model MCC++. A simplification of the photon statistics may lead to very fast calculations of absorption features in the atmosphere. However, these simplifications potentially introduce biases in the results. McSCIA does not use simplifications and is therefore a relatively slow implementation of the equivalence theorem.
An equivalent system of Einstein Equations
Ospino, J.; Hernández-Pastora, J. L.; Núñez, L. A.
2017-03-01
We provide the full set of equations governing the evolution of self-gravitating systems by using a tetrad formalism in General Relativity and the orthogonal splitting of the Riemann tensor. We apply this formalism to spherical case and found that: the only static solution with homogeneous energy density, under the physical reasonable considerations, is the Schwarzchild solution; the conditions under which a non-dissipative fluid is static and finally that shear-free and isotropic pressure conditions are equivalent, for non-dissipative fluids with homogeneous energy density.
Equivalent Circuit Modeling of Hysteresis Motors
Energy Technology Data Exchange (ETDEWEB)
Nitao, J J; Scharlemann, E T; Kirkendall, B A
2009-08-31
We performed a literature review and found that many equivalent circuit models of hysteresis motors in use today are incorrect. The model by Miyairi and Kataoka (1965) is the correct one. We extended the model by transforming it to quadrature coordinates, amenable to circuit or digital simulation. 'Hunting' is an oscillatory phenomenon often observed in hysteresis motors. While several works have attempted to model the phenomenon with some partial success, we present a new complete model that predicts hunting from first principles.
Development and Testing of Living Skin Equivalent.
1988-05-01
Model a) The use of Isografts in an inbred strain of rats. In a preliminary series of experiments the potential use of Fischer strain rats has been...tested by preparing a series of isografts made by grafting skin equivalents with cells from female donors to male hosts. On the average, wound...Autograft--rat 4 1 4 3 5 17 Autograft--rabbit 6 3 1 1 11 Isograft --rat 37 13 13 1 64 Allo fib., iso ker--rat 15 12 3 30 Allo fib, iso ker--rab 8 6 14 Iso
The equivalence principle in a quantum world
DEFF Research Database (Denmark)
Bjerrum-Bohr, N. Emil J.; Donoghue, John F.; El-Menoufi, Basem Kamal;
2015-01-01
the energy is small, we now have the tools to address this conflict explicitly. Despite the violation of some classical concepts, the EP continues to provide the core of the quantum gravity framework through the symmetry - general coordinate invariance - that is used to organize the effective field theory......We show how modern methods can be applied to quantum gravity at low energy. We test how quantum corrections challenge the classical framework behind the equivalence principle (EP), for instance through introduction of nonlocality from quantum physics, embodied in the uncertainty principle. When...
European Equivalencies in Legal Interpreting and Translation
DEFF Research Database (Denmark)
Corsellis, Ann; Hertog, Erik; Martinsen, Bodil
2002-01-01
Within Europe there is increasing freedom of movement between countries and increasing inward migration. As a result, equivalent standards of legl interpreting and translation are required to allow reliable communication for judicial cooperation between member states, for criminal and civil matters...... which cross national borders and for the needs of multilingual populations. The European Convention of Human Rights (article 6, paragrph 3) is one of the main planks of relevant legislation. This international, two year project has been funded by the EU Grotius programme to set out what is required...
The Search for a New Equivalence Principle
Ionescu, Lucian M
2007-01-01
The new emerging quantum physics - quantum computing conceptual bridge, mandates a ``grand unification'' of space-time-matter and quantum information (all quantized), with deep implications for science in general. The major physics revolutions in our understanding of the universe are briefly reviewed and a ``missing'' equivalence principle is identified and its nature explained. An implementation as an external super-symmetry $\\C{E}=ic\\C{P}$ is suggested, generalizing the Wick rotation ``trick''. Taking advantage of the interpretation of entropy as a measure of symmetry, it is naturally asimilated within the present Feynman Path Integral algebraic formalism.
Gravitational leptogenesis, C, CP and strong equivalence
Energy Technology Data Exchange (ETDEWEB)
McDonald, Jamie I.; Shore, Graham M. [Department of Physics, Swansea University,Swansea, SA2 8PP (United Kingdom)
2015-02-12
The origin of matter-antimatter asymmetry is one of the most important outstanding problems at the interface of particle physics and cosmology. Gravitational leptogenesis (baryogenesis) provides a possible mechanism through explicit couplings of spacetime curvature to appropriate lepton (or baryon) currents. In this paper, the idea that these strong equivalence principle violating interactions could be generated automatically through quantum loop effects in curved spacetime is explored, focusing on the realisation of the discrete symmetries C, CP and CPT which must be broken to induce matter-antimatter asymmetry. The related issue of quantum corrections to the dispersion relation for neutrino propagation in curved spacetime is considered within a fully covariant framework.
Hysteretic damping in rotordynamics: An equivalent formulation
Genta, Giancarlo; Amati, Nicola
2010-10-01
The hysteretic damping model cannot be applied to time domain dynamic simulations: this is a well-known feature that has been discussed in the literature since the time when analog computers were widespread. The constant equivalent damping often introduced to overcome this problem is also discussed, and its limitations are stated, in particular those linked with its application in rotordynamics to simulate rotating damping. An alternative model based on the nonviscous damping (NVD) model, but with a limited number of additional degrees of freedom, is proposed, and the relevant equations are derived. Some examples show applications to the rotordynamics field.
Investigating Starburst Galaxy Emission Line Equivalent Widths
Meskhidze, Helen; Richardson, Chris T.
2016-01-01
Modeling star forming galaxies with spectral synthesis codes allows us to study the gas conditions and excitation mechanisms that are necessary to reproduce high ionization emission lines in both local and high-z galaxies. Our study uses the locally optimally-emitting clouds model to develop an atlas of starburst galaxy emission line equivalent widths. Specifically, we address the following question: What physical conditions are necessary to produce strong high ionization emission lines assuming photoionization via starlight? Here we present the results of our photoionization simulations: an atlas spanning 15 orders of magnitude in ionizing flux and 10 orders of magnitude in hydrogen density that tracks over 150 emission lines ranging from the UV to the near IR. Each simulation grid contains ~1.5x104 photoionization models calculated by supplying a spectral energy distribution, grain content, and chemical abundances. Specifically, we will be discussing the effects on the emission line equivalent widths of varying the metallicity of the cloud, Z = 0.2 Z⊙ to Z = 5.0 Z⊙, and varying the star-formation history, using the instantaneous and continuous evolution tracks and the newly released Starburst99 Geneva rotation tracks.
Equivalent circuit analysis of terahertz metamaterial filters
Institute of Scientific and Technical Information of China (English)
Xueqian Zhang; Quan Li; Wei Cao; Weisheng Yue; Jianqiang Gu; Zhen Tian; Jiaguang Han; Weili Zhang
2011-01-01
Metamaterials have been demonstrated over a significant portion of the electromagnetic spectra from radio,microwave,and terahertz (THz) to the optical regimes.The unique properties of metamaterials are not attainable with naturally occurring materials[1].Thus,enormous applications in devices and techniques,such as superlens,cloaking antenna,and sub-wavelength photolithography are enabled[2-5].The capability of metamaterials has been broadly expanded because they allow precise control of the electromagnetic responses.The appreciation of electromagnetic response control through metamaterial structures provides unique benefits in the design of versatile devices,including filters,modulators,and switchable components.%An equivalent circuit model for the analysis and design of terahertz (THz) metamaterial filters is presented. The proposed model, derived based on LMC equivalent circuits, takes into account the detailed geometrical parameters and the presence of a dielectric substrate with the existing analytic expressions for self-inductance, mutual inductance, and capacitance. The model is in good agreement with the experimental measurements and full-wave simulations. Exploiting the circuit model has made it possible to predict accurately the resonance frequency of the proposed structures and thus, quick and accurate process of designing THz device from artificial metamaterials is offered.
Equivalence of open/closed strings
Wang, Peng; Yang, Haitang
2015-01-01
In this paper, we prove that the open and closed strings are $O(D,D)$ equivalent. The equivalence requires an AdS geometry near the boundaries. The $O(D,D)$ invariance is introduced into the Polyakov action by the Tseytlin's action. Traditionally, there exist disconnected open-open or closed-closed configurations in the solution space of the Tseytlin's action. The open-closed configuration is ruled out by the mixed terms of the dual fields. We show that, under some very general guidances, the dual fields are consistently decoupled if and only if the near horizon geometry is $AdS_5$. We then have open-closed and closed-open configurations in different limits of the distances of the $D3$-brane pairs. Inherited from the definition of the theory, these four configurations are of course related to each other by $O(D,D)$ transformations. We therefore conclude that both the open/closed relation and open/closed duality can be derived from $O(D,D)$ symmetries. By analyzing the couplings of the configurations, the low ...
Equivalent Relaxations of Optimal Power Flow
Energy Technology Data Exchange (ETDEWEB)
Bose, S; Low, SH; Teeraratkul, T; Hassibi, B
2015-03-01
Several convex relaxations of the optimal power flow (OPF) problem have recently been developed using both bus injection models and branch flow models. In this paper, we prove relations among three convex relaxations: a semidefinite relaxation that computes a full matrix, a chordal relaxation based on a chordal extension of the network graph, and a second-order cone relaxation that computes the smallest partial matrix. We prove a bijection between the feasible sets of the OPF in the bus injection model and the branch flow model, establishing the equivalence of these two models and their second-order cone relaxations. Our results imply that, for radial networks, all these relaxations are equivalent and one should always solve the second-order cone relaxation. For mesh networks, the semidefinite relaxation and the chordal relaxation are equally tight and both are strictly tighter than the second-order cone relaxation. Therefore, for mesh networks, one should either solve the chordal relaxation or the SOCP relaxation, trading off tightness and the required computational effort. Simulations are used to illustrate these results.
Equivalent magnetization over the World's Ocean
Dyment, J.; Choi, Y.; Hamoudi, M.; Erwan, T.; Lesur, V.
2014-12-01
As a by-product of our recent work to build a candidate model over the oceans for the World Digital Magnetic Anomaly Map (WDMAM) version 2, we derived global distributions of the equivalent magnetization in oceanic domains. In a first step, we use classic point source forward modeling on a spherical Earth to build a forward model of the marine magnetic anomalies at sea-surface. We estimate magnetization vectors using the age map of the ocean floor, the relative plate motions, the apparent polar wander path for Africa, and a geomagnetic reversal time scale. As magnetized source geometry, we assume 1 km-thick layer bearing a 10 A/m magnetization following the topography of the oceanic basement as defined by the bathymetry and sedimentary thickness. Adding a present-day geomagnetic field model allows the computation of our initial magnetic anomaly model. In a second step, we adjust this model to the existing marine magnetic anomaly data, in order to make it consistent with these data. To do so, we extract synthetic magnetic along the ship tracks for which real data are available and we compare quantitatively the measured and computed anomalies on 100, 200 or 400 km-long sliding windows (depending the spreading rate). Among the possible comparison criteria, we discard the maximal range - too dependent on local values - and the correlation and coherency - the geographical adjustment between model and data being not accurate enough - to favor the standard deviation around the mean value. The ratio between the standard deviations of data and model on each sliding window represent an estimate of the magnetization ratio causing the anomalies, which we interpolate to adjust the initial magnetic anomaly model to the data and therefore compute a final model to be included in our WDMAM candidate over the oceanic regions lacking data. The above ratio, after division by the magnetization of 10 A/m used in the model, represents an estimate of the equivalent magnetization under the
Equivalent Resistance in Pulse Electric Current Sintering
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
The sintering resistance for conductive TiB2 and non-conductive Al2O3 as well as empty die during pulse current sintering were investigated in this paper.Equivalent resistances were measured by current and valtage during sintering the conductive and non-conductive materials in the same conditions.It is found that the current paths for conductive are different from those for non-conductive materials.For non-conductive materials,sintering resistances are influenced by powder sizes and heating rates,which indicates that pulse current has some interaction with non-conductive powders.For conductive TiB2,sintering resistances are influenced by heating rates and ball-milling time,which indicates the effect of powders activated by spark.
FUZZY ORDER EQUIVALENT CLASS WITH UNCERTAINTY
Institute of Scientific and Technical Information of China (English)
Wei ZHOU; Mingzhe WANG
2005-01-01
It is a new research topic to create a rational judgment matrix using the cognition theory because of the construction of judgment matrix in AHP involving the decision-maker's cognitive activities.Owing to the presence of uncertain information in the decision procedure, the improper use of the uncertain information will doubtless cause weight changes. In this paper, we add a feedforward process prior to constructing the judgment matrix so that the decision maker can use both the certain and uncertain information to get the initial uncertain rough judgment matrix, and then convert it into a fuzzy matrix. Consequently, it will be better for decision maker to obtain the rough set of order equivalent classes through the decision graph. According to the qualitative analysis, the decision maker can easily construct the final judgment matrix instructed by the rough set created earlier.
Expressivism, Relativism and the analytic equivalence test
Directory of Open Access Journals (Sweden)
Maria J. Frapolli
2015-11-01
Full Text Available The purpose of this paper is to show that, pace (Field 2009, 252, MacFarlane’s assessment relativism and expressivism should be sharply distinguished. We do so by arguing that relativism and expressivism exemplify two very different approaches to context-dependence. Relativism, on the one hand, shares with other contemporary approaches a bottom-up, building block, model, while expressivism is part of a different tradition, one that might include Lewis’ epistemic contextualism and Frege’s content individuation, with which it shares an organic model to deal with context-dependence. The building-block model and the organic model, and thus relativism and expressivism, are set apart with the aid of a particular test: only the building-block model is compatible with the idea that there might be analytically equivalent, and yet different, propositions.
Expressivism, Relativism, and the Analytic Equivalence Test.
Frápolli, Maria J; Villanueva, Neftalí
2015-01-01
The purpose of this paper is to show that, pace (Field, 2009), MacFarlane's assessment relativism and expressivism should be sharply distinguished. We do so by arguing that relativism and expressivism exemplify two very different approaches to context-dependence. Relativism, on the one hand, shares with other contemporary approaches a bottom-up, building block, model, while expressivism is part of a different tradition, one that might include Lewis' epistemic contextualism and Frege's content individuation, with which it shares an organic model to deal with context-dependence. The building-block model and the organic model, and thus relativism and expressivism, are set apart with the aid of a particular test: only the building-block model is compatible with the idea that there might be analytically equivalent, and yet different, propositions.
[The false equivalent Galeazzi in children].
Marzouki, A; Elibrahimi, A; Elmrini, A; Boutayeb, F
2009-02-01
We report the case of a false Galeazzi equivalent in children. This injury is characterised by an epiphyseal detachment of the distal extremity of the ulna rather than a distal radio-ulnar dislocation. A 16-year-old patient was injured in a fall from a bike. Radiographs showed a fracture of the radial shaft with anterior angulation, together with a type II Salter-Harris epiphyseal injury at the level of the distal ulna. We were unable to perform a closed reduction under general anesthesia due to interposition of periosteum at the fracture site. Thus surgical management was the only option, which consisted of removing the offending periosteum and performing osteosynthesis of the radial shaft fracture with a plate, and the epiphyseal detachment with pins. After 10 months, we noted no bone growth disturbance, or any reduced mobility of the wrist. We will continue the follow-up to monitor bone growth disturbance of the distal extremity of the ulna.
Equivalence Bimodule between Spherical Noncommutative Tori
Institute of Scientific and Technical Information of China (English)
Chun Gil PARK
2003-01-01
Let ni,mj ＞ 1. In [5], the spherical noncommutative torus Sppd was defined by twisting Tr+2 × Zl in Tpd C*(Zl) by a totally skew multiplier p on Tr+2 × Zl for Tpd a pd-homogeneous C*-algebra over Пs4i＝1 S2n+I ×Пs2 S2 ×Пs3j＝1 S2mj-1 ×Пs1 S1 × Tr+2. It is shown that Sppd is strongly Morita equivalent to C(Пs4i＝1 S2ni ×Пs2S2×Пs3j＝1 S2mj-1 ×Пs1 S1) C*(Tr+3× Zl, p).
Characterization of Destrins with Different Dextrose Equivalents
Directory of Open Access Journals (Sweden)
Guanglei Li
2010-07-01
Full Text Available Dextrins are widely used for their functional properties and prepared by partial hydrolysis of starch using acid, enzymes, or combinations of both. The physiochemical properties of dextrins are dependent on their molecular distribution and oligosaccharide profiles. In this study, scanning electron microscopy (SEM, X-ray diffractometry (XRD, rapid viscoanalysis (RVA, high-performance Liquid Chromatography (HPLC and gel permeation chromatography (GPC were used to characterize dextrins prepared by common neutral and thermostable α-amylase hydrolysis. The dextrin granules displayed irregular surfaces and were badly damaged by the enzyme treatment. They displayed A-type X-ray diffraction patterns with a decrease of intensity of the characteristic diffraction peaks. The RVA profiles showed that the viscosity of dextrin decreased with the increase of its Dextrose Equivalent (DE value. According to HPLC analysis, the molecular weight, degree of polymerization and the composition of oligosaccharides in dextrins were different.
Equivalent damage validation by variable cluster analysis
Drago, Carlo; Ferlito, Rachele; Zucconi, Maria
2016-06-01
The main aim of this work is to perform a clustering analysis on the damage relieved in the old center of L'Aquila after the earthquake occurred on April 6, 2009 and to validate an Indicator of Equivalent Damage ED that summarizes the information reported on the AeDES card regarding the level of damage and their extension on the surface of the buildings. In particular we used a sample of 13442 masonry buildings located in an area characterized by a Macroseismic Intensity equal to 8 [1]. The aim is to ensure the coherence between the clusters and its hierarchy identified in the data of damage detected and in the data of the ED elaborated.
Premetric equivalent of general relativity: Teleparallelism
Itin, Yakov; Hehl, Friedrich W.; Obukhov, Yuri N.
2017-04-01
In general relativity (GR), the metric tensor of spacetime is essential since it represents the gravitational potential. In other gauge theories (such as electromagnetism), the so-called premetric approach succeeds in separating the purely topological field equation from the metric-dependent constitutive law. We show here that GR allows for a premetric formulation, too. For this purpose, we apply the teleparallel approach of gravity, which represents GR as a gauge theory based on the translation group. We formulate the metric-free topological field equation and a general linear constitutive law between the basic field variables. The requirement of local Lorentz invariance turns the model into a full equivalent of GR. Our approach opens a way for a natural extension of GR to diverse geometrical structures of spacetime.
Equivalency and unbiasedness of grey prediction models
Institute of Scientific and Technical Information of China (English)
Bo Zeng; Chuan Li; Guo Chen; Xianjun Long
2015-01-01
In order to deeply research the structure discrepancy and modeling mechanism among different grey prediction mo-dels, the equivalence and unbiasedness of grey prediction mo-dels are analyzed and verified. The results show that al the grey prediction models that are strictly derived from x(0)(k) +az(1)(k) = b have the identical model structure and simulation precision. Moreover, the unbiased simulation for the homoge-neous exponential sequence can be accomplished. However, the models derived from dx(1)/dt+ax(1) =b are only close to those derived from x(0)(k)+az(1)(k)=b provided that|a|has to satisfy|a| < 0.1; neither could the unbiased simulation for the homoge-neous exponential sequence be achieved. The above conclusions are proved and verified through some theorems and examples.
Isomorphism and Morita equivalence of graph algebras
Abrams, Gene
2008-01-01
For any countable graph $E$, we investigate the relationship between the Leavitt path algebra $L_{\\C}(E)$ and the graph C*-algebra $C^*(E)$. For graphs $E$ and $F$, we examine ring homomorphisms, ring *-homomorphisms, algebra homomorphisms, and algebra *-homomorphisms between $L_{\\C}(E)$ and $L_{\\C}(F)$. We prove that in certain situations isomorphisms between $L_{\\C}(E)$ and $L_{\\C}(F)$ yield *-isomorphisms between the corresponding C*-algebras $C^*(E)$ and $C^*(F)$. Conversely, we show that *-isomorphisms between $C^*(E)$ and $C^*(F)$ produce isomorphisms between $L_{\\C}(E)$ and $L_{\\C}(F)$ in specific cases. The relationship between Leavitt path algebras and graph C*-algebras is also explored in the context of Morita equivalence.
Correlation Measure Equivalence in Dynamic Causal Structures
Gyongyosi, Laszlo
2016-01-01
We prove an equivalence transformation between the correlation measure functions of the causally-unbiased quantum gravity space and the causally-biased standard space. The theory of quantum gravity fuses the dynamic (nonfixed) causal structure of general relativity and the quantum uncertainty of quantum mechanics. In a quantum gravity space, the events are causally nonseparable and all time bias vanishes, which makes it no possible to use the standard causally-biased entropy and the correlation measure functions. Since a corrected causally-unbiased entropy function leads to an undefined, obscure mathematical structure, in our approach the correction is made in the data representation of the causally-unbiased space. We prove that the standard causally-biased entropy function with a data correction can be used to identify correlations in dynamic causal structures. As a corollary, all mathematical properties of the causally-biased correlation measure functions are preserved in the causally-unbiased space. The eq...
The premetric equivalent of general relativity: teleparallelism
Itin, Yakov; Obukhov, Yuri N
2016-01-01
In general relativity (GR), the metric tensor of spacetime is essential since it represents the gravitational potential. In other gauge theories (such as electromagnetism), the so-called premetric approach succeeds in separating the purely topological field equation from the metric-dependent constitutive law. We show here that GR allows for a premetric formulation, too. For this purpose, we apply the teleparallel approach of gravity, which represents GR as a gauge theory based on the translation group. We formulate the metric-free topological field equation and a general linear constitutive law between the basic field variables. The requirement of local Lorentz invariance turns the model into a full equivalent of GR. Our approach opens a way for a natural extension of GR to diverse geometrical structures of spacetime.
Snow water equivalent mapping in Norway
Tveito, O. E.; Udnæs, H.-C.; Engeset, R.; Førland, E. J.; Isaksen, K.; Mengistu, Z.
2003-04-01
In high latitude area snow covers the ground large parts of the year. Information about the water volume as snow is of major importance in many respects. Flood forecasters at NVE need it in order to assess possible flood risks. Hydropower producers need it to plan the most efficient production of the water in their reservoirs, traders to estimate the potential energy available for the market. Meteorologists on their side use the information as boundary conditions in weather forecasting models. The Norwegian meteorological institute has provided snow accumulation maps for Norway for more than 50 years. These maps are now produced twice a month in the winter season. They show the accumulated precipitation in the winter season from the day the permanent snow cover is established. They do however not take melting into account, and do therefore not give a good description of the actual snow amounts during and after periods with snowmelt. Due to an increased need for a direct measure of water volumes as snow cover, met.no and NVE initialized a joint project in order to establish maps of the actual snow cover expressed in water equivalents. The project utilizes recent developments in the use of GIS in spatial modeling. Daily precipitation and temperature are distributed in space by using objective spatial interpolation methods. The interpolation considers topographical and other geographical parameters as well as weather type information. A degree-day model is used at each modeling point to calculate snow-accumulation and snowmelt. The maps represent a spatial scale of 1x1 km2. The modeled snow reservoir is validated by snow pillow values as well traditional snow depth observations. Preliminary results show that the new snow modeling approach reproduces the snow water equivalent well. The spatial approach also opens for a wide use in the terms of areal analysis.
A Solid State Tissue Equivalent Detector for Microdosimetry Project
National Aeronautics and Space Administration — QEL proposes to construct a tissue equivalent microdosimeter using a solid state tissue equivalent detector (SSTED). The Phase I study will produce the working...
Proposed New Test of Equivalence Principle from Rotating Bodies
Institute of Scientific and Technical Information of China (English)
ZHANG Yuan-Zhong; LUO Jun; NIE Yu-Xin
2000-01-01
We study a new kind of equivalence principle for rotating bodies and propose a test of the equivalence principle by comparing free-fall gravitational accelerations of two gyroscopes or a rotating and a non-rotating extended bodies.
On Eugene A. Nida's Functional Equivalence%On Eugene A.Nida's Functional Equivalence
Institute of Scientific and Technical Information of China (English)
赵玲
2016-01-01
Eugene A. Nida's Functional Equivalence is a very useful theory in translation. This theory considers that translation is transference of the source language into the meaning of the target language in the way the author intended the text. It has a deep influence on translation.
Choy, T C
2011-01-01
We clarify the status of the $c$ equivalence principle ($c_u=c$) recently proposed by Heras et al \\cite{JoseAJP2010,JoseEJP2010} and show that its proposal leads to an extension of the current framework of classical relativistic electrodynamics (CRE). This is because in the MLT (mass, length and time) system of units, CRE theory can contain only one fundamental constant of nature and special relativity dictates that this must be $c$, the standard speed of light in vacuum, a point not sufficiently emphasized in most textbooks with the exception of a few such as Panofsky and Phillips \\cite{PanofskyPhillips}. The $c$ equivalence principle Heras \\cite{JoseAJP2010,JoseEJP2010} can be shown to be linked to the second postulate of special relativity which extends the constancy of the unique velocity of light to all of physics (especially to mechanics) other than electromagnetism. An interesting corollary is that both the weak equivalence principle of general relativity and the $c$ equivalence principle are in fact o...
Equivalence above Word Level in English——Chinese Translation
Institute of Scientific and Technical Information of China (English)
王奕君
2008-01-01
Translation is not accomplished by merely substituting words in a word-for-word equivalence.A word-for-word replacement is of little use,because it is only a form of words equivalent,and does not convey the force of meaning(the dynamic equivalence).The aim of this paper is to study equivalence above word level(collocation、idiom and fixed expression)in relation to English--Chinese translation process,using different approaches.
Equivalent layers: another way to look at them
van der Laan, C. J.; Frankena, H. J.
1995-02-01
We describe the behavior of the equivalent refractive index (or Herpin index) and equivalent phase thickness in relation to the phase thicknesses of the layers in a dielectric stack. This relation is visualized by a diagram that provides insight into the existing solutions for given combinations of the Herpin index and the equivalent phase thickness. Furthermore, it can be used for the explanation of the occurrence of stop bands and of the dispersion of equivalent layer stacks.
Equivalent Circuits For AC-Impedance Analysis Of Corrosion
Danford, M. D.
1992-01-01
Report presents investigation of equivalent circuits for ac-impedance analysis of corrosion. Impedance between specimen and electrolyte measured as function of frequency. Data used to characterize corrosion electrochemical system in terms of equivalent circuit. Eleven resistor/capacitor equivalent-circuit models were analyzed.
46 CFR Appendix A to Part 154 - Equivalent Stress
2010-10-01
... 46 Shipping 5 2010-10-01 2010-10-01 false Equivalent Stress A Appendix A to Part 154 Shipping... FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Pt. 154, App. A Appendix A to Part 154—Equivalent Stress I. Equivalent stress (σ c) is calculated by the following formula or another formula...
On the equivalence classes of linear non-autonomous systems *
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
In this paper, the equivalence classification of the linear non-autonomous dynamic systems near singularities is given. Under some conditions their equivalence classes are the same as the autonomous ones. Using a series of linear and nonlinear transforms, the equivalence classification is proved.
Tests of the weak equivalence principle
Speake, C. C.; Will, C. M.
2012-09-01
The Einstein equivalence principle is the foundation for general relativity and all metric theories of gravity. Of its three tenets—the equality of acceleration of test bodies, or weak equivalence principle; the validity of Lorentz invariance in local freely falling frames; and the position invariance of local physical laws—the weak equivalence principle has played the most important role historically, and continues to be a focus of intense theoretical and experimental investigation. From the probably apocryphal 16th century demonstrations by Galileo at Pisa's leaning tower to the sensitive torsion-balance measurements of today (both pictured on the cover of this issue), this principle, dubbed WEP, has been crucial to the development of gravitation theory. The universality of the rate of acceleration of all types of matter in a gravitational field can be taken as evidence that gravitation is fundamentally determined by the geometry, or metric, of spacetime. Newton began his magnum opus 'The Principia' with a discussion of WEP and his experiments to verify it, while Einstein took WEP for granted in his construction of general relativity, never once referring to the epochal experiments by Baron Eötvös. The classic 1964 experiment of Roll, Krotkov and Dicke ushered in the modern era of high-precision tests, and the search for a 'fifth force' during the late 1980s (instigated, ironically, by purported anomalies in Eötvös's old data) caused the enterprise to pivot from pure tests of the foundation of GR to searches for new physics beyond the standard model of the non-gravitational interactions. Today, the next generation of experimental tests of WEP are being prepared for launch or are being developed, with the goal of reaching unprecedented levels of sensitivity, in search of signatures of interactions inspired by string theory, extra dimensions and other concepts from the world of high-energy physics. At the same time observations continue using lunar laser
Researching measurement equivalence in cross-cultural studies
Directory of Open Access Journals (Sweden)
Miloš Kankaraš
2010-06-01
Full Text Available In cross-cultural comparative studies it is essential to establish equivalent measurement of relevant constructs across cultures. If this equivalence is not confirmed it is difficult if not impossible to make meaningful comparison of results across countries. This work presents concept of measurement equivalence, its relationship with other related concepts, different equivalence levels and causes of inequivalence in cross-cultural research. It also reviews three main approaches to the analysis of measurement equivalence – multigroup confirmatory factor analysis, differential item functioning, and multigroup latent class analysis – with special emphasis on their similarities and differences, as well as comparative advantages.
Equivalence Principle and the Baryon Acoustic Peak
Baldauf, Tobias; Simonović, Marko; Zaldarriaga, Matias
2015-01-01
We study the dominant effect of a long wavelength density perturbation $\\delta(\\lambda_L)$ on short distance physics. In the non-relativistic limit, the result is a uniform acceleration, fixed by the equivalence principle, and typically has no effect on statistical averages due to translational invariance. This same reasoning has been formalized to obtain a "consistency condition" on the cosmological correlation functions. In the presence of a feature, such as the acoustic peak at $l_{\\rm BAO}$, this naive expectation breaks down for $\\lambda_L
Topological equivalence for multiple saddle connections
Directory of Open Access Journals (Sweden)
CLEMENTA ALONSO
2002-12-01
Full Text Available We study the topological equivalence between two vector fields defined in the neighborhood of the skeleton of a normal crossings divisor in an ambient space of dimension three. We deal with singularities obtained from local ones by ambient blowing-ups: we impose thus the non-degeneracy condition that they are all hyperbolic without certain algebraic resonances in the set of eigenvalues. Once we cut-out the attractors, we get the result if the corresponding graph has no cycles. The case of cycles is of another nature, as the Dulac Problem in dimension three.Estudamos a equivalência topológica entre dois campos de vetores na vizinhança do esqueleto de um divisor com cruzamento normal, num ambiente de dimensão três. Consideramos singularidades obtidas por explosões a partir de uma singularidade local: isto justifica a condição de hiperbolicidade e não ressonância no conjunto dos autovalores. O resultado principal se obtém quando, depois de retirar os atratores, o grafo resultante não tem ciclos. O caso dos ciclos é de natureza semelhante ao problema de Dulac em dimensão três.
Mathematical Equivalence of Evolution and Design
Directory of Open Access Journals (Sweden)
Leonid Perlovsky
2010-12-01
Full Text Available "Every one who is seriously involved in the pursuit of science becomes convinced that a spirit is manifest in the laws of the Universe." This Einsteinian statement remains outside of science. Our current understanding of the mind mechanisms have come close to explaining spirituality from the scientific point of view. In this paper a theory is presented which is a mathematical breakthrough, overcoming decades of limitations in AI, pattern recognition, neural networks, and other attempts to model the brain-mind. Solutions to engineering problems are presented that have overcome previous difficulties in terms of computational complexity. These solutions result in orders of magnitude improvement in detection, prediction, tracking, fusion, and learning situations. The theory is also extended to higher cognitive functions. It models the knowledge instinct operating in the hierarchy of the human brain-mind. At the top are concepts unifying our entire knowledge; we perceive them as concepts of the meaning and purpose of our existence. This theory is formulated mathematically as dynamic and equivalently as teleological. Experimental results supporting the theory are discussed. The theory overcomes various difficulties, including reductionism, which, in the past, interfered with the acceptance of scientific explanations of the spiritual.
Equivalency of Artificial and Natural Icing
Institute of Scientific and Technical Information of China (English)
wgI Xiao-xing; XU Zhi-hai; LI Zhi-ning; SU Hua-feng; JIA Zhi-dong; GUAN Zhi-cheng
2011-01-01
Climate room is an important instrument to study the icing problems in power networks, and the accuracy of the data from the climate room is under debate. There are many climate rooms in the world, but no standards about the parameters of the climate room such as the room＇s temperature, the velocity of the wind, and the particle diameters of the water droplets etc. These parameters will influence the icing processes on the lines and insulators. This paper gave a summary of the process and the feature of atmospheric icing of power networks. The speed of the icing on a cylinder rod as a new characteristic quantity was proposed to study the de-icing problems in this paper. For the purpose to analyze the equivalence between atmospheric icing and icing in climate room, a finite element model was made based on a small climate room located in the Graduate School at Shenzhen, Tsinghua University. Through the simulation analysis for the heat transfer and flow issues, the result showed that precooling droplets were cooled into supercooled ones soon after they came into the climate room. Based on the most serious icing-speed in Hengshan, Hunan and a series of experiments, the values of some parameters in studying icing problems were proposed to better simulate the atmospheric icing in climate room.
Macrostate equivalence of two general ensembles and specific relative entropies
Mori, Takashi
2016-08-01
The two criteria of ensemble equivalence, i.e., macrostate equivalence and measure equivalence, are investigated for a general pair of states. Macrostate equivalence implies the two ensembles are indistinguishable by the measurement of macroscopic quantities obeying the large-deviation principle, and measure equivalence means that the specific relative entropy of these two states vanishes in the thermodynamic limit. It is shown that measure equivalence implies a macrostate equivalence for a general pair of states by deriving an inequality connecting the large-deviation rate functions to the specific relative Renyi entropies. The result is applicable to both quantum and classical systems. As applications, a sufficient condition for thermalization, the time scale of quantum dynamics of macrovariables, and the second law with strict irreversibility in a quantum quench are discussed.
Carr, Thomas W
2017-02-01
In an SIRS compartment model for a disease we consider the effect of different probability distributions for remaining immune. We show that to first approximation the first three moments of the corresponding probability densities are sufficient to well describe oscillatory solutions corresponding to recurrent epidemics. Specifically, increasing the fraction who lose immunity, increasing the mean immunity time, and decreasing the heterogeneity of the population all favor the onset of epidemics and increase their severity. We consider six different distributions, some symmetric about their mean and some asymmetric, and show that by tuning their parameters such that they have equivalent moments that they all exhibit equivalent dynamical behavior. Copyright © 2016 Elsevier Inc. All rights reserved.
Kinetic simulation of hydrodynamic equivalent capsule implosions
Kwan, Thomas; Le, Ari; Schmitt, Mark; Herrmann, Hans
2016-10-01
We have carried out simulations of direct-drive hydrodynamic equivalent capsule implosion experiments conducted on Omega laser facility at the Laboratory of Laser Energetics of the University of Rochester. The capsules had a glass shell (SiO2) 4.87 μm with an inner diameter of 1086 μm. One was filled with deuterium (D) and tritium (T) at 6.635 and 2.475 atmospheric pressure respectively. The other capsule with D, T, and He-3 at 2.475, 2.475, and 5.55 atmospheric pressure respectively. The capsules were imploded with 60 laser beams with a square pulse length of 0.6ns of total energy of 15.6 kJ. One-dimensional radiation hydrodynamic calculations with HYDRA and kinetic particle/hybrid simulations with LSP are carried out for the post-shot analysis. HYDRA outputs at 0.6ns are linked to LSP, in which the electrons are treated as a fluid while all the ion dynamics is simulated by the standard particle-in-cell technique. Additionally, simulations with the new photon package in LSP are initiated at the beginning of the implosion to include the implosion phase of the capsule. The simulation results of density, temperature, and velocity profiles of the electrons, D, T, He-3, and SiO2species are compared with HYDRA. Detail comparisons among the kinetic simulations, rad-hydro simulations, and experimental results of neutron yield, yield ratio, fusion burn histories, and shell convergence will be presented to assess plasma kinetic effects. Work performed under the auspices of the US DOE by the Los Alamos National Laboratory under Contract No. W7405-ENG-36.
Principle of Spacetime and Black Hole Equivalence
Zhang, Tianxi
2016-06-01
Modelling the universe without relying on a set of hypothetical entities (HEs) to explain observations and overcome problems and difficulties is essential to developing a physical cosmology. The well-known big bang cosmology, widely accepted as the standard model, stands on two fundamentals, which are Einstein’s general relativity (GR) that describes the effect of matter on spacetime and the cosmological principle (CP) of spacetime isotropy and homogeneity. The field equation of GR along with the Friedmann-Lemaitre-Robertson-Walker (FLRW) metric of spacetime derived from CP generates the Friedmann equation (FE) that governs the development and dynamics of the universe. The big bang theory has made impressive successes in explaining the universe, but still has problems and solutions of them rely on an increasing number of HEs such as inflation, dark matter, dark energy, and so on. Recently, the author has developed a new cosmological model called black hole universe, which, instead of making many those hypotheses, only includes a new single postulate (or a new principle) to the cosmology - Principle of Spacetime and Black Hole Equivalence (SBHEP) - to explain all the existing observations of the universe and overcome all the existing problems in conventional cosmologies. This study thoroughly demonstrates how this newly developed black hole universe model, which therefore stands on the three fundamentals (GR, CP, and SBHEP), can fully explain the universe as well as easily conquer the difficulties according to the well-developed physics, thus, neither needing any other hypotheses nor existing any unsolved difficulties. This work was supported by NSF/REU (Grant #: PHY-1263253) at Alabama A & M University.
General Dynamic Equivalent Modeling of Microgrid Based on Physical Background
Directory of Open Access Journals (Sweden)
Changchun Cai
2015-11-01
Full Text Available Microgrid is a new power system concept consisting of small-scale distributed energy resources; storage devices and loads. It is necessary to employ a simplified model of microgrid in the simulation of a distribution network integrating large-scale microgrids. Based on the detailed model of the components, an equivalent model of microgrid is proposed in this paper. The equivalent model comprises two parts: namely, equivalent machine component and equivalent static component. Equivalent machine component describes the dynamics of synchronous generator, asynchronous wind turbine and induction motor, equivalent static component describes the dynamics of photovoltaic, storage and static load. The trajectory sensitivities of the equivalent model parameters with respect to the output variables are analyzed. The key parameters that play important roles in the dynamics of the output variables of the equivalent model are identified and included in further parameter estimation. Particle Swarm Optimization (PSO is improved for the parameter estimation of the equivalent model. Simulations are performed in different microgrid operation conditions to evaluate the effectiveness of the equivalent model of microgrid.
Efficient statistical classification of satellite measurements
Mills, Peter
2012-01-01
Supervised statistical classification is a vital tool for satellite image processing. It is useful not only when a discrete result, such as feature extraction or surface type, is required, but also for continuum retrievals by dividing the quantity of interest into discrete ranges. Because of the high resolution of modern satellite instruments and because of the requirement for real-time processing, any algorithm has to be fast to be useful. Here we describe an algorithm based on kernel estimation called Adaptive Gaussian Filtering that incorporates several innovations to produce superior efficiency as compared to three other popular methods: k-nearest-neighbour (KNN), Learning Vector Quantization (LVQ) and Support Vector Machines (SVM). This efficiency is gained with no compromises: accuracy is maintained, while estimates of the conditional probabilities are returned. These are useful not only to gauge the accuracy of an estimate in the absence of its true value, but also to re-calibrate a retrieved image and...
Improving Estuarine Transport Models using Satellite Measurements
2013-09-30
standard methods (Siegel,2005; Palacios et al., 2009; Doxaran et. al. 2009, Hu et. al. 2004), we estimate turbidity and water temperature by regessing...mass conservation. Estuaries and Coasts, 30p.1095-1105. Palacios , L. Sherry. Tawnya D. Peterson., Raphael M. Kudela. (2009). Development of
Equivalent Effect in the Translation of Culture-Bound Terms
Institute of Scientific and Technical Information of China (English)
无
2012-01-01
In the book Toward a Science of Translation,Eugene Nida brings out two important concepts:formal-equivalence(to reveal as much as possible of the form and content of the original message) and dynamic-equivalence(the closest natural equivalent to the source-language message).(Nida,1964) When we translate from poetry to poetry,prose to prose,novel to novel,we try to achieve F-E as much as possible
Stress Response of Offshore Structures by Equivalent Polynomial Expansion Techniques
DEFF Research Database (Denmark)
Sigurdsson, Gudfinnur; Nielsen, Søren R.K.
This paper concerns an investigation of the effects of nonlinearity of drag loading on offshore structures excited by 2D wave fields, where the nonlinear term in the Morison equation is replaced by an equivalent cubic expansion. The equivalent cubic expansion coefficients for the equivalent drag...... model are obtained using the least mean square procedure. Numerical results are given. The displacement response and stress response processes obtained using the above loading model are compared with simulation results and those obtained from equivalent linearization of the drag term....
An improved model of Robinson equivalent circuit analytical model
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
The Robinson equivalent circuit analytical model can be used only in calculating shielding effectiveness of enclosure with the same multi-holes in one wall, but cannot be used in different multi-holes in two walls. According to the practical requirement, this article uses Konefal’s and Farhana’s characteristic impedance of apertures to improve the equivalent circuit analytical model in different multi-holes in two walls. The improved equivalent circuit analytical model is more useful than Robinson equivalent circuit analytical model. In the article, all kinds of enclosures are simulated by TLM (Transmission-Line Matrix method) to prove that this improved model is feasible in multimode.
Estimating Equivalency of Explosives Through A Thermochemical Approach
Energy Technology Data Exchange (ETDEWEB)
Maienschein, J L
2002-07-08
The Cheetah thermochemical computer code provides an accurate method for estimating the TNT equivalency of any explosive, evaluated either with respect to peak pressure or the quasi-static pressure at long time in a confined volume. Cheetah calculates the detonation energy and heat of combustion for virtually any explosive (pure or formulation). Comparing the detonation energy for an explosive with that of TNT allows estimation of the TNT equivalency with respect to peak pressure, while comparison of the heat of combustion allows estimation of TNT equivalency with respect to quasi-static pressure. We discuss the methodology, present results for many explosives, and show comparisons with equivalency data from other sources.
Reconsidering the Equivalence in Translation From Cultural Differences Perspective
Institute of Scientific and Technical Information of China (English)
LI Yinling
2009-01-01
Translation involves language as well as culture. Cultural similarities exist in languages; however cultural differences have an essential bearing upon translation. Even approximate equivalent and loan words have different implications and usages in English and Chinese. So, this challenges the traditional concept of equivalence as a constitutive feature of translation. To an author, there is no such thing as absolute equivalence in the context of E-C translation for the simple reason that Chinese and English belong to two entirely different cultural traditions. However, through careful comparative studies, relative equivalents can be achieved.
Wind, Galina; DaSilva, Arlindo M.; Norris, Peter M.; Platnick, Steven E.
2013-01-01
In this paper we describe a general procedure for calculating equivalent sensor radiances from variables output from a global atmospheric forecast model. In order to take proper account of the discrepancies between model resolution and sensor footprint the algorithm takes explicit account of the model subgrid variability, in particular its description of the probably density function of total water (vapor and cloud condensate.) The equivalent sensor radiances are then substituted into an operational remote sensing algorithm processing chain to produce a variety of remote sensing products that would normally be produced from actual sensor output. This output can then be used for a wide variety of purposes such as model parameter verification, remote sensing algorithm validation, testing of new retrieval methods and future sensor studies. We show a specific implementation using the GEOS-5 model, the MODIS instrument and the MODIS Adaptive Processing System (MODAPS) Data Collection 5.1 operational remote sensing cloud algorithm processing chain (including the cloud mask, cloud top properties and cloud optical and microphysical properties products.) We focus on clouds and cloud/aerosol interactions, because they are very important to model development and improvement.
43 CFR 426.11 - Class 1 equivalency.
2010-10-01
.... Equivalency determinations can be made only on a district-wide basis. (c) Definition of Class 1 land. Class 1... measured in terms of net income per acre (reflecting both productivity and costs of production). The... farm income will be the measure of productivity to establish equivalency factors reflecting the...
Perverse equivalences, BB-tilting, mutations and applications
Ladkani, Sefi
2010-01-01
We relate the notions of BB-tilting and perverse derived equivalence at a vertex. Based on these notions, we define mutations of algebras, leading to derived equivalent ones. We present applications to endomorphism algebras of cluster-tilting objects in 2-Calabi-Yau categories and to algebras of global dimension at most 2.
40 CFR 63.469 - Equivalent methods of control.
2010-07-01
... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Equivalent methods of control. 63.469 Section 63.469 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Standards for Halogenated Solvent Cleaning § 63.469 Equivalent methods of control. Upon written application...
Inter Digital Transducer Modelling through Mason Equivalent Circuit Model
DEFF Research Database (Denmark)
Mishra, Dipti; Singh, Abhishek; Hussain, Dil muhammed Akbar
2016-01-01
The frequency reliance of inter-digital transducer is analyzed with the help of MASON’s Equivalent circuit which is based on Smith’s Equivalent circuit which is further based on Foster’sNetwork. An inter-digital transducer has been demonstratedas a RLC network. The circuit is simulated by Simulat...
Inter digital transducer modelling through Mason equivalent circuit model
DEFF Research Database (Denmark)
Mishra, Dipti; Singh, Abhishek; Hussain, Dil muhammed Akbar
2016-01-01
The frequency reliance of inter-digital transducer is analyzed with the help of MASON's Equivalent circuit which is based on Smith's Equivalent circuit which is further based on Foster's Network. An inter-digital transducer has been demonstrated as a RLC network. The circuit is simulated by Simul...
On the equivalence of brushlet and wavelet bases
DEFF Research Database (Denmark)
Nielsen, Morten; Borup, Lasse
2005-01-01
We prove that the Meyer wavelet basis and a class of brushlet systems associated with exponential type partitions of the frequency axis form a family of equivalent (unconditional) bases for the Besov and Triebel-Lizorkin function spaces. This equivalence is then used to obtain new results on nonl...
40 CFR 133.105 - Treatment equivalent to secondary treatment.
2010-07-01
... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Treatment equivalent to secondary treatment. 133.105 Section 133.105 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS SECONDARY TREATMENT REGULATION § 133.105 Treatment equivalent to secondary...
Assessment Battery for Communication: Development of Two Equivalent Forms
Bosco, Francesca M.; Angeleri, Romina; Zuffranieri, Marco; Bara, Bruno G.; Sacco, Katiuscia
2012-01-01
The aim of this paper was to develop and test two equivalent forms of the Assessment Battery for Communication (ABaCo), a tool for evaluating pragmatic abilities in patients with neuropsychological and psychiatric disorders. The equivalent forms were created using the data from a sample of 390 children, then tested in a sample of 30 patients with…
Stimulus Equivalence, Generalization, and Contextual Stimulus Control in Verbal Classes
Sigurdardottir, Zuilma Gabriela; Mackay, Harry A.; Green, Gina
2012-01-01
Stimulus generalization and contextual control affect the development of equivalence classes. Experiment 1 demonstrated primary stimulus generalization from the members of trained equivalence classes. Adults were taught to match six spoken Icelandic nouns and corresponding printed words and pictures to one another in computerized three-choice…
Theory of Covariance Equivalent ARMAV Models of Civil Engineering Structures
DEFF Research Database (Denmark)
Andersen, P.; Brincker, Rune; Kirkegaard, Poul Henning
1996-01-01
In this paper the theoretical background for using covariance equivalent ARMAV models in modal analysis is discussed. It is shown how to obtain a covariance equivalent ARMA model for a univariate linear second order continous-time system excited by Gaussian white noise. This result is generalized...
Equivalent Widths of 15 Extrasolar-Planet Host Stars
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
We present the equivalent widths of 15 extrasolar-planet host stars.These data were based on the high-resolution, high signal-to-noise ratio spectra obtained with the 2.16 m telescope at Xinglong station. The error in the Xinglong equivalent width is estimated by a comparison of these data with those given in previous studies of common stars.
IMPROVED RANDOMIZED ALGORITHM FOR THE EQUIVALENT 2-CATALOG SEGMENTATION PROBLEM
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
An improved randomized algorithm of the equivalent 2-catalog segmentation problem is presented. The result obtained in this paper makes some progress to answer the open problem by analyze this algorithm with performance guarantee. A 0.6378-approximation for the equivalent 2-catalog segmentation problem is obtained.
- Synonymy in the Translation Equivalent Paradigms of a Standard ...
African Journals Online (AJOL)
given is truly a functional translation equivalent for the lemma and make sure that the ... a whole, with the concept of partial synonymy as the point of focus. ..... order in which these equivalents are listed, is based on intuitive frequency and.
Theory of Covariance Equivalent ARMAV Models of Civil Engineering Structures
DEFF Research Database (Denmark)
Andersen, P.; Brincker, Rune; Kirkegaard, Poul Henning
In this paper the theoretical background for using covariance equivalent ARMAV models in modal analysis is discussed. It is shown how to obtain a covariance equivalent ARMA model for a univariate linear second order continuous-time system excited by Gaussian white noise. This result is generalize...
Theory of Covariance Equivalent ARMAV Models of Civil Engineering Structures
DEFF Research Database (Denmark)
Andersen, P.; Brincker, Rune; Kirkegaard, Poul Henning
1996-01-01
In this paper the theoretical background for using covariance equivalent ARMAV models in modal analysis is discussed. It is shown how to obtain a covariance equivalent ARMA model for a univariate linear second order continous-time system excited by Gaussian white noise. This result is generalized...
On the equivalence of brushlet and wavelet bases
DEFF Research Database (Denmark)
Borup, Lasse; Nielsen, Morten
We prove that the Meyer wavelet basis and a class of brushlet systems associated with exponential type partitions of the frequency axis form a family of equivalent (unconditional) bases for the Besov and Triebel-Lizorkin function spaces. This equivalence is then used to obtain new results...
ROUTING AND WAVELENGTH ASSIGNMENT ALGORITHMS BASED ON EQUIVALENT NETWORKS
Institute of Scientific and Technical Information of China (English)
Qi Xiaogang; Liu Lifang; Lin Sanyang
2006-01-01
In this paper, a Wavelength Division Multiplexing (WDM) network model based on the equivalent networks is described, and wavelength-dependent equivalent arc, equivalent networks, equivalent multicast tree and some other terms are presented. Based on this model and relevant Routing and Wavelength Assignment (RWA) strategy, a unicast RWA algorithm and a multicast RWA algorithm are presented. The wavelength-dependent equivalent arc expresses the schedule of local RWA and the equivalent network expresses the whole topology of WDM optical networks, so the two algorithms are of the flexibility in RWA and the optimization of the whole problem. The theoretic analysis and simulation results show the two algorithms are of the stronger capability and the lower complexity than the other existing algorithms for RWA problem, and the complexity of the two algorithms are only related to the scale of the equivalent networks. Finally, we prove the two algorithms' feasibility and the one-by-one corresponding relation between the equivalent multicast tree and original multicast tree, and point out the superiorities and drawbacks of the two algorithms respectively.
Equivalence of dynamical ensembles and Navier-Stokes equations
Gallavotti, G
1996-01-01
A reversible version of the Navier Stokes equation is studied. A conjecture emerges stating the equivalence between the reversible equation and the usual Navier Stokes equation. The latter appears as a statement of ensembles equivalence in the limit of infinite Reynolds number, which plays the role of the thermodynamic limit.
Pandya, Shwetang N; Peterson, Byron J; Kobayashi, Masahiro; Pandya, Santosh P; Mukai, Kiyofumi; Sano, Ryuichi
2014-12-01
The infrared imaging video bolometer (IRVB) used for measurement of the two-dimensional (2D) radiation profiles from the Large Helical Device has been significantly upgraded recently to improve its signal to noise ratio, sensitivity, and calibration, which ultimately provides quantitative measurements of the radiation from the plasma. The reliability of the quantified data needs to be established by various checks. The noise estimates also need to be revised and more realistic values need to be established. It is shown that the 2D heat diffusion equation can be used for estimating the power falling on the IRVB foil, even with a significant amount of spatial variation in the thermal diffusivity across the area of the platinum foil found experimentally during foil calibration. The equation for the noise equivalent power density (NEPD) is re-derived to include the errors in the measurement of the thermophysical and the optical properties of the IRVB foil. The theoretical value estimated using this newly derived equation matches closely, within 5.5%, with the mean experimental value. The change in the contribution of each error term of the NEPD equation with rising foil temperature is also studied and the blackbody term is found to dominate the other terms at elevated operating temperatures. The IRVB foil is also sensitive to the charge exchange (CX) neutrals escaping from the plasma. The CX neutral contribution is estimated to be marginally higher than the noise equivalent power (NEP) of the IRVB. It is also established that the radiation measured by the IRVB originates from the impurity line radiation from the plasma and not from the heated divertor tiles. The change in the power density due to noise reduction measures such as data smoothing and averaging is found to be comparable to the IRVB NEPD. The precautions that need to be considered during background subtraction are also discussed with experimental illustrations. Finally, the analysis algorithm with all the
Assessment Battery for Communication: development of two equivalent forms.
Bosco, Francesca M; Angeleri, Romina; Zuffranieri, Marco; Bara, Bruno G; Sacco, Katiuscia
2012-01-01
The aim of this paper was to develop and test two equivalent forms of the Assessment Battery for Communication (ABaCo), a tool for evaluating pragmatic abilities in patients with neuropsychological and psychiatric disorders. The equivalent forms were created using the data from a sample of 390 children, then tested in a sample of 30 patients with traumatic brain injury. Equivalent forms of the same test are useful in clinical practice and intervention research, when performance needs to be tested on two separate occasions, for example before and after a rehabilitation program. The present results provide additional evidence on the psychometric functioning of the equivalent forms of the ABaCo and their usability in a clinical context. The reader will be able to discuss the evidence of the psychometric propriety of the equivalent forms of the ABaCo and describe its potential usefulness. Copyright © 2012 Elsevier Inc. All rights reserved.
Hasenohrl and the Equivalence of Mass and Energy
Boughn, Stephen
2011-01-01
In 1904 Austrian physicist Fritz Hasenohrl (1874-1915) examined blackbody radiation in a reflecting cavity. By calculating the work necessary to keep the cavity moving at a constant velocity against the radiation pressure he concluded that to a moving observer the energy of the radiation would appear to increase by an amount E=(3/8)mc^2, which in early 1905 he corrected to E=(3/4)mc^2. Because relativistic corrections come in at order v^2/c^2 and Hasenohrl's gedankenexperiment evidently required calculations only to order v/c, it is initially puzzling why he did not achieve the answer universally accepted today. Moreover, that $m$ should be equal to (4/3)E/c^2 has led commentators to believe that this problem is identical to the famous "4/3 problem" of the self-energy of the electron and they have invariably attributed Hasenohrl's mistake to neglect of the cavity stresses. We examine Hasenohrl's papers from a modern, relativistic point of view in an attempt to understand where exactly he went wrong. The probl...
Directory of Open Access Journals (Sweden)
Dror G. Feitelson
2004-01-01
Full Text Available The services provided by digital libraries can be much improved by correctly identifying variants of the same name. For example, this will allow for better retrieval of all the works by a certain author. We focus on variants caused by abbreviations of first names, and show that significant achievements are possible by simple lexical analysis and comparison of names. This is done in two steps: first a pairwise matching of names is performed, and then these are used to find cliques of equivalent names. However, these steps can each be performed in a variety of ways. We therefore conduct an experimental analysis using two real datasets to find which approaches actually work well in practice. Interestingly, this depends on the size of the repository, as larger repositories may have many more similar names.
Equivalence versus classical statistical tests in water quality assessments.
Ngatia, Murage; Gonzalez, David; San Julian, Steve; Conner, Arin
2010-01-01
To evaluate whether two unattended field organic carbon instruments could provide data comparable to laboratory-generated data, we needed a practical assessment. Null hypothesis statistical testing (NHST) is commonly utilized for such evaluations in environmental assessments, but researchers in other disciplines have identified weaknesses that may limit NHST's usefulness. For example, in NHST, large sample sizes change p-values and a statistically significant result can be obtained by merely increasing the sample size. In addition, p-values can indicate that observed results are statistically significantly different, but in reality the differences could be trivial in magnitude. Equivalence tests, on the other hand, allow the investigator to incorporate decision criteria that have practical relevance to the study. In this paper, we demonstrate the potential use of equivalence tests as an alternative to NHST. We first compare data between the two field instruments, and then compare the field instruments' data to laboratory-generated data using both NHST and equivalence tests. NHST indicated that the data between the two field instruments and the data between the field instruments and the laboratory were significantly different. Equivalence tests showed that the data were equivalent because they fell within a pre-determined equivalence interval based on our knowledge of laboratory precision. We conclude that equivalence tests provide more useful comparisons and interpretation of water quality data than NHST and should be more widely used in similar environmental assessments.
Pragmatic Equivalence in Different Translations of The Merchant of Venice
Institute of Scientific and Technical Information of China (English)
白婕
2015-01-01
Pragmatic equivalence, meaning to transfer the implied meaning of the source text to the target text, usually involves the receiver to whom the translation is directed. Two notions are crucial in translation to achieve pragmatic equivalence:context and optimal relevance. In light of these two element, the author in this paper conducts a case study by using Shakespeare’s play The Merchant of Venice and two Chinese versions from Zhu Shenghao and Sun Dayu as data, by comparing these two versions to explore how pragmatic equivalence in translation can be achieve at lexical, semantic and cultural levels.
Criterion for SLOCC equivalence of multipartite quantum states
Zhang, Tinggui; Zhao, Ming-Jing; Huang, Xiaofen
2016-10-01
We study the stochastic local operation and classical communication (SLOCC) equivalence for arbitrary dimensional multipartite quantum states. For multipartite pure states, we present a necessary and sufficient criterion in terms of their coefficient matrices. This condition can be used to classify some SLOCC equivalent quantum states with coefficient matrices having the same rank. For multipartite mixed state, we provide a necessary and sufficient condition by means of the realignment of matrix. Some detailed examples are given to identify the SLOCC equivalence of multipartite quantum states.
An investigation of TNT equivalence of hemispherical PE4 charges
Rigby, S.E.; Sielicki, P.W.
2014-01-01
The TNT equivalence of an explosive is given as the equivalent mass of TNT required to produce a blast wave of equal magnitude to that produced by a unit weight of the explosive in question. Currently, there is a lack of agreement in the literature on the TNT equivalence (TNTeq) of PE4. This paper presents a combined numerical and experimental investigation of TNTeq for hemispherical PE4 charges in far-field blast events. Experimental results are compared to a series of numerical analyses con...
A Dixmier-Moeglin equivalence for skew Laurent polynomial rings
Parks, James William Alexander
2009-01-01
The work of Dixmier in 1977 and Moeglin in 1980 show us that for a prime ideal $P$ in the universal enveloping algebra of a complex finite-dimensional Lie algebra the properties of being primitive, rational and locally closed in the Zariski topology are all equivalent. This equivalence is referred to as the Dixmier-Moeglin equivalence. In this thesis we will study skew Laurent polynomial rings of the form ${mathbb{C}}[x_1,ldots,x_d][z,z^{-1};sigma]$ where $sigma$ is a ${mathbb{C}}$-algebra au...
Inference systems for observation equivalences in the π-calculus
Institute of Scientific and Technical Information of China (English)
林惠民
1999-01-01
Inference systems for observation equivalences in the pi-calculus with recursion are proposed, and their completeness over the finite-control fragment with guarded recursions are proven. The inference systems consist of inference rules and equational axioms. The judgments are conditional equations which characterise symbolic bisimulations between process terms. This result on the one hand generalises Milner’s complete axiomatisation of observation equivalence for regular CCS to the pi-calculus, and on the other hand extends the proof systems of strong bisimulations for guarded regular pi-calculus to observation equivalences.
An improved equivalent circuit model of radial mode piezoelectric transformer.
Huang, Yihua; Huang, Wei
2011-05-01
In this paper, both the equivalent circuit models of the radial mode and the coupled thickness vibration mode of the radial mode piezoelectric transformer are deduced, and then with the Y-parameter matrix method and the dual-port network theory, an improved equivalent circuit model for the multilayer radial mode piezoelectric transformer is established. A radial mode transformer sample is tested to verify the equivalent circuit model. The experimental results show that the model proposed in this paper is more precise than the typical model.
Spaces of homotopy self-equivalences a survey
Rutter, John W
1997-01-01
This survey covers groups of homotopy self-equivalence classes of topological spaces, and the homotopy type of spaces of homotopy self-equivalences. For manifolds, the full group of equivalences and the mapping class group are compared, as are the corresponding spaces. Included are methods of calculation, numerous calculations, finite generation results, Whitehead torsion and other areas. Some 330 references are given. The book assumes familiarity with cell complexes, homology and homotopy. Graduate students and established researchers can use it for learning, for reference, and to determine the current state of knowledge.
Singularity theory of fitness functions under dimorphism equivalence.
Wang, Xiaohui; Golubitsky, Martin
2016-09-01
We apply singularity theory to classify monomorphic singular points as they occur in adaptive dynamics. Our approach is based on a new equivalence relation called dimorphism equivalence, which is the largest equivalence relation on strategy functions that preserves ESS singularities, CvSS singularities, and dimorphisms. Specifically, we classify singularities up to topological codimension two and compute their normal forms and universal unfoldings. These calculations lead to the classification of local mutual invasibility plots that can be seen generically in systems with two parameters.
Lattice Study of Planar Equivalence: The Quark Condensate
Armoni, Adi; Patella, Agostino; Pica, Claudio
2008-01-01
We study quenched SU(N) gauge theories with fermions in the two-index symmetric, antisymmetric and the adjoint representations. Our main motivation is to check whether at large number of colours those theories become non-perturbatively equivalent. We prove the equivalence assuming that the charge-conjugation symmetry is not broken in pure Yang-Mills theory. We then carry out a quenched lattice simulation of the quark condensate in the symmetric, antisymmetric and the adjoint representations for SU(2), SU(3), SU(4), SU(6) and SU(8). We show that the data support the equivalence and discuss the size of subleading corrections.
Energy Technology Data Exchange (ETDEWEB)
Ono, Kaoru; Endo, Satoru; Tanaka, Kenichi; Hoshi, Masaharu; Hirokawa, Yutaka [Department of Radiation Physics, Hiroshima Heiwa Clinic, 1-31 Kawaramachi, Naka-ku, Hiroshima 730-0856 (Japan); Quantum Energy Applications, Graduate School of Engineering, Hiroshima University, 4-1 Kagamiyama, Higashi-Hiroshima 730-8527 (Japan); Center of Medical Education, Sapporo Medical University, 17 Minami 1 Jo, Chuo-ku, Sapporo 060-8556 (Japan); Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553 (Japan); Department of Radiation Oncology, Hiroshima Heiwa Clinic, 1-31 Kawaramachi, Naka-ku, Hiroshima 730-0856 (Japan)
2010-08-15
Purpose: In this study, the authors evaluated the accuracy of dose calculations performed by the convolution/superposition based anisotropic analytical algorithm (AAA) in lung equivalent heterogeneities with and without bone equivalent heterogeneities. Methods: Calculations of PDDs using the AAA and Monte Carlo simulations (MCNP4C) were compared to ionization chamber measurements with a heterogeneous phantom consisting of lung equivalent and bone equivalent materials. Both 6 and 10 MV photon beams of 4x4 and 10x10 cm{sup 2} field sizes were used for the simulations. Furthermore, changes of energy spectrum with depth for the heterogeneous phantom using MCNP were calculated. Results: The ionization chamber measurements and MCNP calculations in a lung equivalent phantom were in good agreement, having an average deviation of only 0.64{+-}0.45%. For both 6 and 10 MV beams, the average deviation was less than 2% for the 4x4 and 10x10 cm{sup 2} fields in the water-lung equivalent phantom and the 4x4 cm{sup 2} field in the water-lung-bone equivalent phantom. Maximum deviations for the 10x10 cm{sup 2} field in the lung equivalent phantom before and after the bone slab were 5.0% and 4.1%, respectively. The Monte Carlo simulation demonstrated an increase of the low-energy photon component in these regions, more for the 10x10 cm{sup 2} field compared to the 4x4 cm{sup 2} field. Conclusions: The low-energy photon by Monte Carlo simulation component increases sharply in larger fields when there is a significant presence of bone equivalent heterogeneities. This leads to great changes in the build-up and build-down at the interfaces of different density materials. The AAA calculation modeling of the effect is not deemed to be sufficiently accurate.
Calorimetric measurement and modelling of the equivalent series of capacitors
Seguin, B.; Gosse, J. P.; Ferrieux, J. P.
1999-12-01
The equivalent series resistance of polypropylene capacitors has been determined under rated voltage, in the range 1 kHz 1 MHz, between 220 K and 370 K by a calorimetric technique. The original feature of this determination of capacitor losses lies in the use of the isothermal calorimetry and in the measurement of an electrical power and not of a temperature increase. The frequency dependence of the equivalent series resistance, at various temperatures, enables to separate the losses in the conducting material from those in the dielectric and to get their respective variations as a function of frequency and temperature. These variations of the equivalent series resistance with frequency at a given temperature have been reproduced by using an equivalent circuit composed of resistors, inductors and capacitors. This model has been verified for non-sinusoidal waveforms such as those met with in a filtering circuit and is used to evaluate by simulation the losses of the capacitor.
Evaluation of pharmaceutical and chemical equivalence of selected ...
African Journals Online (AJOL)
Personal
tests to determine their pharmaceutical and chemical equivalence and the possibility of substituting ... market. Some years later, many generics containing diclofenac became available, which ..... important for the regulatory body to be more.
Deformed Heisenberg algebra with minimal length and equivalence principle
Tkachuk, V M
2013-01-01
Studies in string theory and quantum gravity lead to the Generalized Uncertainty Principle (GUP) and suggest the existence of a fundamental minimal length which, as was established, can be obtained within the deformed Heisenberg algebra. The first look on the classical motion of bodies in a space with corresponding deformed Poisson brackets in a uniform gravitational field can give an impression that bodies of different mass fall in different ways and thus the equivalence principle is violated. Analyzing the kinetic energy of a composite body we find that the motion of its center of mass in the deformed space depends on some effective parameter of deformation. It gives a possibility to recover the equivalence principle in the space with deformed Poisson brackets. and thus GUP is reconciled with the equivalence principle. We also show that the independence of kinetic energy on composition leads to the recovering of the equivalence principle in the space with deformed Poisson brackets.
Are Superfluid Vortices in Pulsars Violating the Weak Equivalence Principle?
de Matos, Clovis Jacinto
2010-01-01
In the present paper we argue that timing irregularities in pulsars, like glitches and timing noise, could be associated with the violation of the weak equivalence principle for vortices in the superfluid core of rotating neutron stars.
Approved Drug Products with Therapuetic Equivalence Evaluations (Orange Book)
U.S. Department of Health & Human Services — The publication Approved Drug Products with Therapeutic Equivalence Evaluations (the List, commonly known as the Orange Book) identifies drug products approved on...
A Unified Framework for Equivalence Verification of Datapath Oriented Applications
Alizadeh, Bijan; Fujita, Masahiro
In this paper, we introduce a unified framework based on a canonical decision diagram called Horner Expansion Diagram (HED) [1] for the purpose of equivalence checking of datapath oriented hardware designs in various design stages from an algorithmic description to the gate-level implementation. The HED is not only able to represent and manipulate algorithmic specifications in terms of polynomial expressions with modulo equivalence but also express bit level adder (BLA) description of gate-level implementations. Our HED can support modular arithmetic operations over integer rings of the form Z2n. The proposed techniques have successfully been applied to equivalence checking on industrial benchmarks. The experimental results on different applications have shown the significant advantages over existing bit-level and also word-level equivalence checking techniques.
Development of an Equivalent Wind Plant Power-Curve: Preprint
Energy Technology Data Exchange (ETDEWEB)
Wan, Y. H.; Ela, E.; Orwig, K.
2010-06-01
Development of an equivalent wind plant power-curve becomes highly desirable and useful in predicting plant output for a given wind forecast. Such a development is described and summarized in this paper.
The transfer of avoidance evoking functions through stimulus equivalence classes.
Augustson, E M; Dougher, M J
1997-09-01
Recent research in the area of stimulus equivalence suggests that transfer of function via members of stimulus equivalence classes may have relevance to human emotional responding and the development and generalization of certain psychological disorders. This study investigated the transfer of avoidance evoking functions through equivalence classes. Eight subjects were trained in the necessary relations for two-four member stimulus equivalence classes to emerge. Next, using an on-baseline classical conditioning procedure, one member of one class was paired with shock while one member of the other class was presented without shock. Then, while subjects engaged a key-press task, a differential, signalled avoidance task was introduced wherein shock was avoided if a response occurred to the stimulus previously associated with shock. The remaining stimuli from both classes were then presented. The behavior of all eight subjects showed the differential transfer of the avoidance evoking function. The clinical and theoretical implications of the results are discussed.
The associativity of equivalence and the Towers of Hanoi problem
Backhouse, Roland; Fokkinga, Maarten
2001-01-01
Dijkstra and Scholten have argued that greater use should be made of the associativity of equivalence. This note shows how the property is used in specifying the rotation of the disks in the well-known Towers of Hanoi problem.
Analysis of equivalent antenna based on FDTD method
Institute of Scientific and Technical Information of China (English)
Yun-xing YANG; Hui-chang ZHAO; Cui DI
2014-01-01
An equivalent microstrip antenna used in radio proximity fuse is presented. The design of this antenna is based on multilayer multi-permittivity dielectric substrate which is analyzed by finite difference time domain (FDTD) method. Equivalent iterative formula is modified in the condition of cylindrical coordinate system. The mixed substrate which contains two kinds of media (one of them is air)takes the place of original single substrate. The results of equivalent antenna simulation show that the resonant frequency of equivalent antenna is similar to that of the original antenna. The validity of analysis can be validated by means of antenna resonant frequency formula. Two antennas have same radiation pattern and similar gain. This method can be used to reduce the weight of antenna, which is significant to the design of missile-borne antenna.
ESA GlobSnow Snow Water Equivalent (SWE)
National Aeronautics and Space Administration — The European Space Agency (ESA) Global Snow Monitoring for Climate Research (GlobSnow) snow water equivalent (SWE) v2.0 data record contains snow information derived...
Approved Drug Products with Therapuetic Equivalence Evaluations (Orange Book)
U.S. Department of Health & Human Services — The publication Approved Drug Products with Therapeutic Equivalence Evaluations (the List, commonly known as the Orange Book) identifies drug products approved on...
Why were Matrix Mechanics and Wave Mechanics considered equivalent?
Perovic, Slobodan
A recent rethinking of the early history of Quantum Mechanics deemed the late 1920s agreement on the equivalence of Matrix Mechanics and Wave Mechanics, prompted by Schrödinger's 1926 proof, a myth. Schrödinger supposedly failed to prove isomorphism, or even a weaker equivalence ("Schrödinger-equivalence") of the mathematical structures of the two theories; developments in the early 1930s, especially the work of mathematician von Neumann provided sound proof of mathematical equivalence. The alleged agreement about the Copenhagen Interpretation, predicated to a large extent on this equivalence, was deemed a myth as well. In response, I argue that Schrödinger's proof concerned primarily a domain-specific ontological equivalence, rather than the isomorphism or a weaker mathematical equivalence. It stemmed initially from the agreement of the eigenvalues of Wave Mechanics and energy-states of Bohr's Model that was discovered and published by Schrödinger in his first and second communications of 1926. Schrödinger demonstrated in this proof that the laws of motion arrived at by the method of Matrix Mechanics are satisfied by assigning the auxiliary role to eigenfunctions in the derivation of matrices (while he only outlined the reversed derivation of eigenfunctions from Matrix Mechanics, which was necessary for the proof of both isomorphism and Schrödinger-equivalence of the two theories). This result was intended to demonstrate the domain-specific ontological equivalence of Matrix Mechanics and Wave Mechanics, with respect to the domain of Bohr's atom. And although the mathematical equivalence of the theories did not seem out of the reach of existing theories and methods, Schrödinger never intended to fully explore such a possibility in his proof paper. In a further development of Quantum Mechanics, Bohr's complementarity and Copenhagen Interpretation captured a more substantial convergence of the subsequently revised (in light of the experimental results) Wave
Exact equivalent straight waveguide model for bent and twisted waveguides
DEFF Research Database (Denmark)
Shyroki, Dzmitry
2008-01-01
Exact equivalent straight waveguide representation is given for a waveguide of arbitrary curvature and torsion. No assumptions regarding refractive index contrast, isotropy of materials, or particular morphology in the waveguide cross section are made. This enables rigorous full-vector modeling o...... of in-plane curved or helically wound waveguides with use of available simulators for straight waveguides without the restrictions of the known approximate equivalent-index formulas....
On the Equivalence of Euler-Lagrange and Noether Equations
Energy Technology Data Exchange (ETDEWEB)
Faliagas, A. C., E-mail: apostol.faliagas@gmail.com [University of Athens, Department of Mathematics (Greece)
2016-03-15
We prove that, under the condition of nontriviality, the Euler-Lagrange and Noether equations are equivalent for a general class of scalar variational problems. Examples are position independent Lagrangians, Lagrangians of p-Laplacian type, and Lagrangians leading to nonlinear Poisson equations. As applications we prove certain propositions concerning the nonlinear Poisson equation and its generalisations, and the equivalence of admissible and inner variations for the systems under consideration.
On the existence of certainty equivalents of various relevant types
Directory of Open Access Journals (Sweden)
J. C. R. Alcantud
2003-01-01
Full Text Available We tackle the problem of associating certainty equivalents with preferences over stochastic situations, which arises in a number of different fields (e.g., the theory of risk attitudes or the analysis of stochastic cooperative games. We study the possibility of endowing such preferences with certainty equivalence functionals that satisfy relevant requirements (such as positive homogeneity, translation invariance, monotonicity with respect to first-order stochastic dominance, and subadditivity. Uniqueness of the functional is also addressed in fairly general conditions.
On Functional Equivalence in the English version of Leiyu
Institute of Scientific and Technical Information of China (English)
王飞娟; 许焕荣
2014-01-01
In drama translation, both performability and the individual characteristics of the work should be given adequate con-sideration. This paper applies the Functional Equivalence Theory to analyzing Thunderstorm, the English version of Leiyu, a fa-mous Chinese play, converting some unique features of the Chinese original into their English equivalents on linguistic, cultural and stylistic levels without affecting the performability of the drama.
The Physical Mirror Equivalence for the Local P^2
Cacciatori, Sergio Luigi; Guerra, Stefano
2013-01-01
In this paper we consider the total space of the canonical bundle of P^2 and we use a proposal by Hosono, together with results in Seidel and Auroux-Katzarkov-Orlov, to deduce the right physical mirror equivalence between D^b(K_{P^2}) and the derived Fukaya category of its mirror. By construction, our equivalence is compatible with the mirror map between moduli spaces and with the computation of Gromov--Witten invariants.
A Derived Transfer of Mood Functions through Equivalence Relations
Barnes-Holmes, Yvonne; Barnes-Holmes, Dermot; Smeets, Paul M.; Luciano, Carmen
2004-01-01
The present study investigated the transfer of induced happy and sad mood functions through equivalence relations. Sixteen subjects participated in a combined equivalence and mood induction procedure. In Phase 1, all subjects were trained in 2 conditional discriminations using a matching-to-sample format (i.e., A1-B1, A2-B2, A1-C1, A2-C2). In…
Solving complex-valued linear systems via equivalent real formulations
Energy Technology Data Exchange (ETDEWEB)
DAY,DAVID M.; HEROUX,MICHAEL A.
2000-05-22
Most algorithms used in preconditioned iterative methods are generally applicable to complex valued linear systems, with real valued linear systems simply being a special case. However, most iterative solver packages available today focus exclusively on real valued systems, or deal with complex valued systems as an afterthought. One obvious approach to addressing this problem is to recast the complex problem into one of a several equivalent real forms and then use a real valued solver to solve the related system. However, well-known theoretical results showing unfavorable spectral properties for the equivalent real forms have diminished enthusiasm for this approach. At the same time, experience has shown that there are situations where using an equivalent real form can be very effective. In this paper, the authors explore this approach, giving both theoretical and experimental evidence that an equivalent real form can be useful for a number of practical situations. Furthermore, they show that by making good use of some of the advance features of modem solver packages, they can easily generate equivalent real form preconditioners that are computationally efficient and mathematically identical to their complex counterparts. Using their techniques, they are able to solve very ill-conditioned complex valued linear systems for a variety of large scale applications. However, more importantly, they shed more light on the effectiveness of equivalent real forms and more clearly delineate how and when they should be used.
Diminished acquired equivalence yet good discrimination performance in older participants.
Robinson, Jasper; Owens, Emma
2013-01-01
We asked younger and older human participants to perform computer-based configural discriminations that were designed to detect acquired equivalence. Both groups solved the discriminations but only the younger participants demonstrated acquired equivalence. The discriminations involved learning the preferences ["like" (+) or "dislike" (-)] for sports [e.g., tennis (t) and hockey (h)] of four fictitious people [e.g., Alice (A), Beth (B), Charlotte (C), and Dorothy (D)]. In one experiment, the discrimination had the form: At+, Bt-, Ct+, Dt-, Ah-, Bh+, Ch-, Dh+. Notice that, e.g., Alice and Charlotte are "equivalent" in liking tennis but disliking hockey. Acquired equivalence was assessed in ancillary components of the discrimination (e.g., by looking at the subsequent rate of "whole" versus "partial" reversal learning). Acquired equivalence is anticipated by a network whose hidden units are shared when inputs (e.g., A and C) signal the same outcome (e.g., +) when accompanied by the same input (t). One interpretation of these results is that there are age-related differences in the mechanisms of configural acquired equivalence.
The transfer of Cfunc contextual control through equivalence relations.
Perez, William F; Fidalgo, Adriana P; Kovac, Roberta; Nico, Yara C
2015-05-01
Derived relational responding is affected by contextual stimuli (Cfunc) that select specific stimulus functions. The present study investigated the transfer of Cfunc contextual control through equivalence relations by evaluating both (a) the maintenance of Cfunc contextual control after the expansion of a relational network, and (b) the establishment of novel contextual stimuli by the transfer of Cfunc contextual control through equivalence relations. Initially, equivalence relations were established and contingencies were arranged so that colors functioned as Cfunc stimuli controlling participants' key-pressing responses in the presence of any stimulus from a three-member equivalence network. To investigate the first research question, the three-member equivalence relations were expanded to five members and the novel members were presented with the Cfunc stimuli in the key-pressing task. To address the second goal of this study, the colors (Cfunc) were established as equivalent to certain line patterns. The transfer of contextual cue function (Cfunc) was tested replacing the colored backgrounds with line patterns in the key-pressing task. Results suggest that the Cfunc contextual control was transferred to novel stimuli that were added to the relational network. In addition, the line patterns indirectly acquired the contextual cue function (Cfunc) initially established for the colored backgrounds. The conceptual and applied implications of Cfunc contextual control are discussed. © Society for the Experimental Analysis of Behavior.
Directory of Open Access Journals (Sweden)
David eGarratt-Reed
2016-05-01
Full Text Available There has been a recent rapid growth in the number of psychology courses offered online through institutions of higher education. The American Psychological Association (APA has highlighted the importance of ensuring the effectiveness of online psychology courses. Despite this, there have been inconsistent findings regarding student grades, satisfaction, and retention in online psychology units. Equivalency Theory posits that online and classroom-based learners will attain equivalent learning outcomes when equivalent learning experiences are provided. We present a case study of an online introductory psychology unit designed to provide equivalent learning experiences to the pre-existing face-to-face version of the unit. Academic performance, student feedback, and retention data from 866 Australian undergraduate psychology students were examined to assess whether the online unit produced comparable outcomes to the ‘traditional’ unit delivered face-to-face. Student grades did not significantly differ between modes of delivery, except for a group-work based assessment where online students performed more poorly. Student satisfaction was generally high in both modes of the unit, with group-work the key source of dissatisfaction in the online unit. The results provide partial support for Equivalency Theory. The group-work based assessment did not provide an equivalent learning experience for students in the online unit highlighting the need for further research to determine effective methods of engaging students in online group activities. Consistent with previous research, retention rates were significantly lower in the online unit, indicating the need to develop effective strategies to increase online retention rates. While this study demonstrates successes in presenting online students with an equivalent learning experience, we recommend that future research investigates means of successfully facilitating collaborative group-work assessment
May, J. C.; Bourassa, M. A.
2010-12-01
Satellite measured winds, such as those reported by the SeaWinds scatterometer onboard the QuikSCAT satellite, can be validated with in situ data. The in situ data used for comparison with SeaWinds should be collocated in both time and space; however, due to the sparseness of data and time sampling intervals of the in situ data, ideally collocated observations are rare. Therefore, in situ data within a certain time and space range to the satellite overpass are used. This approach results in a total variance from three primary sources: variance in SeaWinds, variance in the comparison data, and variance associated with the temporal and spatial difference. The purpose of this study is to determine the amount of variance due to the temporal and spatial difference between two observations, in particular the equivalent neutral wind speed reported by SeaWinds and in situ data. Initially, this natural variability is examined in an idealized scenario where only in situ data is considered: the one-minute observations collected through the Shipboard Automated Meteorological and Oceanographic System (SAMOS) initiative from 2005 through 2009. The satellite is assumed to pass over the ship on the hour every hour. Shifts in time are used to examine the error associated with a mismatch in time. Taylor’s hypothesis can be used to translate a temporal shift to a spatial shift. The results show that the variance associated with the temporal difference increases as the mismatch in time increases. The temporal variance can also be separated into wind speed groups, which shows that there is a larger amount of variance associated with higher wind speeds. Confirmation of the idealized case method and results is done by using collocated SeaWinds and SAMOS observations. The comparison uses the closest collocation in both time and space to the satellite overpass. The total variance associated with a time shift from 0 to 60 minutes is estimated as the root mean square sum of the temporal
ASCERTAINMENT OF THE EQUIVALENT CIRCUIT PARAMETERS OF THE ASYNCHRONOUS MACHINE
Directory of Open Access Journals (Sweden)
V. S. Safaryan
2015-01-01
Full Text Available The article considers experimental and analytical determination of the asynchronous machine equivalent-circuit parameters with application of the reference data. Transient processes investigation of the asynchronous machines necessitates the equivalent circuit parameters (resistance impedance, inductances and coefficient of the stator-rotor contours mutual inductance that help form the transitory-process mathematical simulation model. The reference books do not provide those parameters; they instead give the rated ones (active power, voltage, slide, coefficient of performance and capacity coefficient as well as the ratio of starting and nominal currents and torques. The noted studies on the asynchronous machine equivalent-circuits parametrization fail to solve the problems ad finem or solve them with admissions. The paper presents experimental and analytical determinations of the asynchronous machine equivalent-circuit parameters: the experimental one based on the results of two measurements and the analytical one where the problem boils down to solving a system of nonlineal algebraic equations. The authors investigate the equivalent asynchronous machine input-resistance properties and adduce the dependence curvatures of the input-resistances on the slide. They present a symbolic model for analytical parameterization of the asynchronous machine equivalent-circuit that represents a system of nonlineal equations and requires one of the rotor-parameters arbitrary assignment. The article demonstrates that for the asynchronous machine equivalent-circuit experimental parameterization the measures are to be conducted of the stator-circuit voltage, current and active power with two different slides and arbitrary assignment of one of the rotor parameters. The paper substantiates the fact that additional measurement does not discard the rotor-parameter choice arbitrariness. The authors establish that in motoring mode there is a critical slide by which the
Validity of the Aluminum Equivalent Approximation in Space Radiation Shielding
Badavi, Francis F.; Adams, Daniel O.; Wilson, John W.
2009-01-01
The origin of the aluminum equivalent shield approximation in space radiation analysis can be traced back to its roots in the early years of the NASA space programs (Mercury, Gemini and Apollo) wherein the primary radiobiological concern was the intense sources of ionizing radiation causing short term effects which was thought to jeopardize the safety of the crew and hence the mission. Herein, it is shown that the aluminum equivalent shield approximation, although reasonably well suited for that time period and to the application for which it was developed, is of questionable usefulness to the radiobiological concerns of routine space operations of the 21 st century which will include long stays onboard the International Space Station (ISS) and perhaps the moon. This is especially true for a risk based protection system, as appears imminent for deep space exploration where the long-term effects of Galactic Cosmic Ray (GCR) exposure is of primary concern. The present analysis demonstrates that sufficiently large errors in the interior particle environment of a spacecraft result from the use of the aluminum equivalent approximation, and such approximations should be avoided in future astronaut risk estimates. In this study, the aluminum equivalent approximation is evaluated as a means for estimating the particle environment within a spacecraft structure induced by the GCR radiation field. For comparison, the two extremes of the GCR environment, the 1977 solar minimum and the 2001 solar maximum, are considered. These environments are coupled to the Langley Research Center (LaRC) deterministic ionized particle transport code High charge (Z) and Energy TRaNsport (HZETRN), which propagates the GCR spectra for elements with charges (Z) in the range I shield, and the effects of the aluminum equivalent approximation for a good polymeric shield material such as genetic polyethylene (PE). The shield thickness is represented by a 25 g/cm spherical shell. Although one could
Sequential time interleaved random equivalent sampling for repetitive signal
Zhao, Yijiu; Liu, Jingjing
2016-12-01
Compressed sensing (CS) based sampling techniques exhibit many advantages over other existing approaches for sparse signal spectrum sensing; they are also incorporated into non-uniform sampling signal reconstruction to improve the efficiency, such as random equivalent sampling (RES). However, in CS based RES, only one sample of each acquisition is considered in the signal reconstruction stage, and it will result in more acquisition runs and longer sampling time. In this paper, a sampling sequence is taken in each RES acquisition run, and the corresponding block measurement matrix is constructed using a Whittaker-Shannon interpolation formula. All the block matrices are combined into an equivalent measurement matrix with respect to all sampling sequences. We implemented the proposed approach with a multi-cores analog-to-digital converter (ADC), whose ADC cores are time interleaved. A prototype realization of this proposed CS based sequential random equivalent sampling method has been developed. It is able to capture an analog waveform at an equivalent sampling rate of 40 GHz while sampled at 1 GHz physically. Experiments indicate that, for a sparse signal, the proposed CS based sequential random equivalent sampling exhibits high efficiency.
Equivalent-Continuum Modeling With Application to Carbon Nanotubes
Odegard, Gregory M.; Gates, Thomas S.; Nicholson, Lee M.; Wise, Kristopher E.
2002-01-01
A method has been proposed for developing structure-property relationships of nano-structured materials. This method serves as a link between computational chemistry and solid mechanics by substituting discrete molecular structures with equivalent-continuum models. It has been shown that this substitution may be accomplished by equating the vibrational potential energy of a nano-structured material with the strain energy of representative truss and continuum models. As important examples with direct application to the development and characterization of single-walled carbon nanotubes and the design of nanotube-based devices, the modeling technique has been applied to determine the effective-continuum geometry and bending rigidity of a graphene sheet. A representative volume element of the chemical structure of graphene has been substituted with equivalent-truss and equivalent continuum models. As a result, an effective thickness of the continuum model has been determined. This effective thickness has been shown to be significantly larger than the interatomic spacing of graphite. The effective thickness has been shown to be significantly larger than the inter-planar spacing of graphite. The effective bending rigidity of the equivalent-continuum model of a graphene sheet was determined by equating the vibrational potential energy of the molecular model of a graphene sheet subjected to cylindrical bending with the strain energy of an equivalent continuum plate subjected to cylindrical bending.
Diminished acquired equivalence yet good discrimination performance in older participants
Directory of Open Access Journals (Sweden)
Jasper eRobinson
2013-10-01
Full Text Available We asked younger and older human participants to perform computer-based configural discriminations that were designed to detect acquired equivalence. Both groups solved the discriminations but only the younger participants demonstrated acquired equivalence. The discriminations involved learning the preferences (‘like’ [+] or ‘dislike’ [-] for sports (e.g., tennis [t] and hockey [h] of four fictitious people (e.g., Alice [A], Beth [B], Charlotte [C] & Dorothy [D]. In one experiment, the discrimination had the form: At+, Bt-, Ct+, Dt-, Ah-, Bh+, Ch-, Dh+. Notice that, e.g., Alice and Charlotte are ‘equivalent’ in liking tennis but disliking hockey. Acquired equivalence was assessed in ancillary components of the discrimination (e.g., by looking at the subsequent rate of ‘whole’ versus ‘partial’ reversal learning. Acquired equivalence is anticipated by a network whose hidden units are shared when inputs (e.g., A and C signal the same outcome (e.g., + when accompanied by the same input (t. One interpretation of these results is that there are age-related differences in the mechanisms of configural acquired equivalence.
The equivalent depth of burst for impact cratering
Holsapple, K. A.
1980-01-01
The concept of modeling an impact cratering event with an explosive event with the explosive buried at some equivalent depth of burst (d.o.b.) is discussed. Various and different ways to define this equivalent d.o.b. are identified. Recent experimental results for a dense quartz sand are used to determine the equivalent d.o.b. for various conditions of charge type, event size, and impact conditions. The results show a decrease in equivalent d.o.b. with increasing energy for fixed impact velocity and a decrease in equivalent d.o.b. with increasing velocity for fixed energy. The values for an iron projectile are on the order of 2-3 projectile radii for energy equal to one ton of TNT, decreasing to about 1.5 radii at a megaton of TNT. The dependence on projectile and target mass density matches that included in common jet-penetration formulas for projectile densities greater than target densities and for the higher energies.
Inductions and restrictions for stable equivalences of Morita type
Chen, Hongxing; Xi, Changchang
2010-01-01
In this paper, we present two methods, induction and restriction procedures, to construct new stable equivalences of Morita type. Suppose that a stable equivalence of Morita type between two algebras $A$ and $B$ is defined by a $B$-$A$-bimodule $N$. Then, for any finite admissible set $\\Phi$ and any generator $X$ of the $A$-module category, the $\\Phi$-Auslander-Yoneda algebras of $X$ and $N\\otimes_AX$ are stably equivalent of Morita type. Moreover, under certain conditions, we transfer stable equivalences of Morita type between $A$ and $B$ to ones between $eAe$ and $fBf$, where $e$ and $f$ are idempotent elements in $A$ and $B$, respectively. Consequently, for self-injective algebras $A$ and $B$ over a field without semisimple direct summands, and for any $A$-module $X$ and $B$-module $Y$, if the $\\Phi$-Auslander-Yoneda algebras of $A\\oplus X$ and $B\\oplus Y$ are stably equivalent of Morita type for one finite admissible set $\\Phi$, then so are the $\\Psi$-Auslander-Yoneda algebras of $A\\oplus X$ and $B\\oplus ...
A Cp-theory problem book functional equivalencies
Tkachuk, Vladimir V
2016-01-01
This fourth volume in Vladimir Tkachuk's series on Cp-theory gives reasonably complete coverage of the theory of functional equivalencies through 500 carefully selected problems and exercises. By systematically introducing each of the major topics of Cp-theory, the book is intended to bring a dedicated reader from basic topological principles to the frontiers of modern research. The book presents complete and up-to-date information on the preservation of topological properties by homeomorphisms of function spaces. An exhaustive theory of t-equivalent, u-equivalent and l-equivalent spaces is developed from scratch. The reader will also find introductions to the theory of uniform spaces, the theory of locally convex spaces, as well as the theory of inverse systems and dimension theory. Moreover, the inclusion of Kolmogorov's solution of Hilbert's Problem 13 is included as it is needed for the presentation of the theory of l-equivalent spaces. This volume contains the most important classical re...
The European Person Equivalent: Measuring the personal environmental space
DEFF Research Database (Denmark)
Hauschild, Michael Zwicky; Wenzel, Henrik
2001-01-01
and interpretation of environmental impacts from all kinds of man-made activities, technologies and systems. The paper presents the determination of the person equivalents for different impact categories and consumption of resources. Its relation to the sustainability-based ecological space and its use as a common......The European person equivalent (PE) is a quantification of the environmental impact caused annually by the activities of an average European. It comprises contributions to all the major environmental impacts from global to local as well as our consumption of resources. Similarly, the targeted...... European person equivalent is a quantification of the average person’s environmental impact in a near future according to the current politically set environmental targets. In addition to expressing the current societal priorities in pollution reduction, the targeted PE expresses the environmental space...
A REVISED SOLUTION OF EQUIVALENT PERMEABILITY TENSOR FOR DISCONTINUOUS FRACTURES
Institute of Scientific and Technical Information of China (English)
HE Ji; CHEN Sheng-hong; SHAHROUR Isam
2012-01-01
The equivalent permeability tensor is essential to the application of the equivalent porous media model in the numerical seepage simulation for fractured rock masses.In this paper,a revised solution of the equivalent permeability tensor is proposed to represent the influence of the fracture connectivity in discontinuous fractures.A correction coefficient is involved to reflect the complex seepage flow type through the rock bridge.This correction coefficient is back analyzed from single-hole packer tests,based on the Artificial Neural Network (ANN) back analysis and the Finite Element Method (FEM) seepage simulation.The limitation of this back analysis algorithm is that the number of single-hole packer tests should be equal or greater than the number of fracture sets,and three is the maximum number of the fracture sets.The proposed solution and the back analysis algorithm are applied in the permeability measurement and the seepage simulation for the Xiaowan arch dam foundation.
Field tests of a tissue-equivalent beta survey meter
Energy Technology Data Exchange (ETDEWEB)
Martz, D.E.; Johnson, L.O.; Rich, B.L.; Daniel, S.H.
1986-01-01
A tissue-equivalent survey meter for monitoring the (dD/dt)(0.07) and (dD/dt)(10) dose rates produced by betas and photons has been designed and tested. The very thin tissue-equivalent plastic scintillator closely simulates the critical skin tissue layer between 4 mg.cm/sup -2/ and 9 mg.cm/sup -2/. The meter is calibrated to read the (dD/dt)(0.07) dose rate directly, and the (dD/dt)(10) dose rate behind a filter. Laboratory measurements of calibrated sources and field tests have demonstrated tissue-equivalent response of the survey meter to betas between 70 keV and 2500 keV and to photons with energies greater than about 30 keV.
Topological equivalence between the Fibonacci quasicrystal and the Harper model.
Kraus, Yaacov E; Zilberberg, Oded
2012-09-14
One-dimensional quasiperiodic systems, such as the Harper model and the Fibonacci quasicrystal, have long been the focus of extensive theoretical and experimental research. Recently, the Harper model was found to be topologically nontrivial. Here, we derive a general model that embodies a continuous deformation between these seemingly unrelated models. We show that this deformation does not close any bulk gaps, and thus prove that these models are in fact topologically equivalent. Remarkably, they are equivalent regardless of whether the quasiperiodicity appears as an on-site or hopping modulation. This proves that these different models share the same boundary phenomena and explains past measurements. We generalize this equivalence to any Fibonacci-like quasicrystal, i.e., a cut and project in any irrational angle.
Inter Digital Transducer Modelling through Mason Equivalent Circuit Model
DEFF Research Database (Denmark)
Mishra, Dipti; Singh, Abhishek; Hussain, Dil muhammed Akbar
2016-01-01
by Simulation program with Integrated Circuit Emphasis (HSPICE), a well-liked electronic path simulator. The acoustic wave devices are not suitable to simulation through circuit simulator.In this paper, an electrical model of Mason’s Equivalent electricalcircuit for an inter-digital transducer (IDT......The frequency reliance of inter-digital transducer is analyzed with the help of MASON’s Equivalent circuit which is based on Smith’s Equivalent circuit which is further based on Foster’sNetwork. An inter-digital transducer has been demonstratedas a RLC network. The circuit is simulated......) is projected which is well-suitedwith a broadlycast-offuniversalresolution circuit simulator SPICE built-in out with the proficiency to simulatethenegative capacitances and inductances. The investigationis done to prove the straightforwardness of establishing the frequency and time domain physical...
Wave propagation in equivalent continuums representing truss lattice materials
Energy Technology Data Exchange (ETDEWEB)
Messner, Mark C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Barham, Matthew I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kumar, Mukul [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Barton, Nathan R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2015-07-29
Stiffness scales linearly with density in stretch-dominated lattice meta-materials offering the possibility of very light yet very stiff structures. Current additive manufacturing techniques can assemble structures consisting of these lattice materials, but the design of such structures will require accurate, efficient simulation techniques. Equivalent continuum models have several advantages over discrete truss models of stretch dominated lattices, including computational efficiency and ease of model construction. However, the development an equivalent model suitable for representing the dynamic response of a periodic truss is complicated by microinertial effects. This paper derives a dynamic equivalent continuum model for periodic truss structures and verifies it against detailed finite element simulations. The model must incorporate microinertial effects to accurately reproduce long-wavelength characteristics of the response such as anisotropic elastic soundspeeds. The formulation presented here also improves upon previous work by preserving equilibrium at truss joints for affine lattice deformation and by improving numerical stability by eliminating vertices in the effective yield surface.
Testing for Equivalence: A Methodology for Computational Cognitive Modelling
Stewart, Terrence; West, Robert
2010-12-01
The equivalence test (Stewart and West, 2007; Stewart, 2007) is a statistical measure for evaluating the similarity between a model and the system being modelled. It is designed to avoid over-fitting and to generate an easily interpretable summary of the quality of a model. We apply the equivalence test to two tasks: Repeated Binary Choice (Erev et al., 2010) and Dynamic Stocks and Flows (Gonzalez and Dutt, 2007). In the first case, we find a broad range of statistically equivalent models (and win a prediction competition) while identifying particular aspects of the task that are not yet adequately captured. In the second case, we re-evaluate results from the Dynamic Stocks and Flows challenge, demonstrating how our method emphasizes the breadth of coverage of a model and how it can be used for comparing different models. We argue that the explanatory power of models hinges on numerical similarity to empirical data over a broad set of measures.
A Model for Semantic Equivalence Discovery for Harmonizing Master Data
Piprani, Baba
IT projects often face the challenge of harmonizing metadata and data so as to have a "single" version of the truth. Determining equivalency of multiple data instances against the given type, or set of types, is mandatory in establishing master data legitimacy in a data set that contains multiple incarnations of instances belonging to the same semantic data record . The results of a real-life application define how measuring criteria and equivalence path determination were established via a set of "probes" in conjunction with a score-card approach. There is a need for a suite of supporting models to help determine master data equivalency towards entity resolution—including mapping models, transform models, selection models, match models, an audit and control model, a scorecard model, a rating model. An ORM schema defines the set of supporting models along with their incarnation into an attribute based model as implemented in an RDBMS.
Dynamic equivalences in the hard-sphere dynamic universality class.
López-Flores, Leticia; Ruíz-Estrada, Honorina; Chávez-Páez, Martín; Medina-Noyola, Magdaleno
2013-10-01
We perform systematic simulation experiments on model systems with soft-sphere repulsive interactions to test the predicted dynamic equivalence between soft-sphere liquids with similar static structure. For this we compare the simulated dynamics (mean squared displacement, intermediate scattering function, α-relaxation time, etc.) of different soft-sphere systems, between them and with the hard-sphere liquid. We then show that the referred dynamic equivalence does not depend on the (Newtonian or Brownian) nature of the microscopic laws of motion of the constituent particles, and hence, applies independently to colloidal and to atomic simple liquids. Finally, we verify another more recently proposed dynamic equivalence, this time between the long-time dynamics of an atomic liquid and its corresponding Brownian fluid (i.e., the Brownian system with the same interaction potential).
The origins and use of the equivalent temperature concept
Energy Technology Data Exchange (ETDEWEB)
Eason, E.D. [Modeling and Computing Services LLC, P.O. Box 18583, Boulder, CO 80308-1583 (United States); Hall, G. [Nuclear Graphite Research Group, MACE, University of Manchester, P.O. Box 88, Manchester M60 1QD (United Kingdom)], E-mail: graham.n.hall@manchester.ac.uk; Heys, G.B. [Health and Safety Executive, Redgrave Court, Merton Road, Bootle, Merseyside L20 7HS (United Kingdom); Knott, J.F. [Metallurgy and Materials, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Marsden, B.J. [Nuclear Graphite Research Group, MACE, University of Manchester, P.O. Box 88, Manchester M60 1QD (United Kingdom); Preston, S.D. [Serco Assurance, Thomson House, Birchwood Park, Risley, Warrington, Cheshire WA3 6GA (United Kingdom); Swan, T
2008-10-31
In some graphite research fields, it is accepted practice to apply an equivalent temperature correction when using graphite data from facilities with differing fast neutron fluxes. The origins of the equivalent temperature hypothesis are described, including the data and theory originally used to justify the approach, and some reservations that have been expressed by various authors are discussed. Relevant findings of recent statistically based work on Gilsocarbon materials irradiated in test reactors at differing flux are presented. The data originally used for justifying the approach and the more recent data analyses both suggest that the use of equivalent temperatures may be justified at low temperatures but not at temperatures above about 300-350 deg. C. Unfortunately the quantity and quality of the data does not allow for a more exact temperature to be defined.
Equivalence Principles, Spacetime Structure and the Cosmic Connection
Ni, Wei-Tou
2015-01-01
After reviewing the meaning of various equivalence principles and the structure of electrodynamics, we give a fairly detailed account of the construction of the light cone and a core metric from the equivalence principle for the photon (no birefringence, no polarization rotation and no amplification/attenuation in propagation) in the framework of linear electrodynamics using cosmic connections/observations as empirical support. The cosmic nonbirefringent propagation of photons independent of energy and polarization verifies the Galileo Equivalence Principle [Universality of Propagation] for photons/electromagnetic wave packets in spacetime. This nonbirefringence constrains the spacetime constitutive tensor to high precision to a core metric form with an axion degree and a dilaton degree of freedom. Thus comes the metric with axion and dilation. Constraints on axion and dilaton from astrophysical/cosmic propagation are reviewed. E\\"otv\\"os-type experiments, Hughes-Drever-type experiments, redshift experiments ...
A semi-quantitative equivalence for abstracting from fast reactions
Galpin, Vashti; Ciocchetta, Federica; 10.4204/EPTCS.67.5
2011-01-01
Semantic equivalences are used in process algebra to capture the notion of similar behaviour, and this paper proposes a semi-quantitative equivalence for a stochastic process algebra developed for biological modelling. We consider abstracting away from fast reactions as suggested by the Quasi-Steady-State Assumption. We define a fast-slow bisimilarity based on this idea. We also show congruence under an appropriate condition for the cooperation operator of Bio-PEPA. The condition requires that there is no synchronisation over fast actions, and this distinguishes fast-slow bisimilarity from weak bisimilarity. We also show congruence for an operator which extends the reactions available for a species. We characterise models for which it is only necessary to consider the matching of slow transitions and we illustrate the equivalence on two models of competitive inhibition.
TNT Equivalency of Unconfined Aerosols of Propylene Oxide
Directory of Open Access Journals (Sweden)
A. Apparao
2014-09-01
Full Text Available The unconfined aerosols of propylene oxide (PO are formed by dispersing the fuel in air. These aerosols undergo detonation by suitable initiation and produce high impulse blast. Tri-nitro Toluene (TNT equivalence is an important parameter used to represent the power of explosive materials and compare their relative damage effects wrt TNT. The parameters commonly used for estimation of TNT equivalency are total energy of explosive source and properties of resulting blast wave, viz., blast peak overpressure and positive impulse. In the present study, the unconfined aerosols of 4.2 kg PO were formed by breaking open the cylindrical canister with the help of axially positioned central burster charge and then detonated using a secondary explosive charge after a preset time delay. The resulting blast profiles were recorded and the blast parameters were analysed. Being a non-ideal explosive source, the TNT equivalency depends on fraction of total energy utilised for blast formation, the rate of energy release, cloud dimensions, and concentration of fuel. Hence, various approaches based on energy release, experimental blast profiles, triangulated blast parameters, and ground reflected blast parameters were considered to determine the TNT equivalency of unconfined PO aerosols. It was observed that the TNT equivalency is not a single value but vary with distance. The paper provides various options for weapon designer to choose a suitable approach for considering TNT equivalency. The scaling laws established from the experimental data of unconfined aerosols of PO for blast peak over pressure and scaled impulse help in predicting the performance for different values of fuel weight and distance.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.431-437, DOI:http://dx.doi.org/10.14429/dsj.64.6851
Offsetting Ongoing Methane Emissions --- An Alternative to Emission Equivalence Metrics
Clisby, N.; Enting, I. G.; Lauder, A.; Carter, J.; Cowie, A.; Henry, B.; Raupach, M. R.
2012-12-01
The Global Warming Potential (GWP) has been widely adopted as a metric for comparing the climate impact of different greenhouse gases. As has been frequently noted, there are many problems with using GWPs to define emission equivalence in spite of the use of GWPs for this purpose in contexts such as the Kyoto Protocol. We propose that for methane, rather than define emission equivalence, the appropriate comparison is between ongoing emissions of 0.9 to 1.0 kg of CH4 per year and one-off emissions of 1 tonne of carbon. This approach represents an approximate solution to the inverse problem of defining a forcing equivalent index (FEI) that gives exact equivalence of radiative forcing over a range of timescales. In our approach, if ongoing methane emissions are offset by a one-off carbon removal that is built up with 40-year e-folding time, then the result is close to radiatively neutral over periods from years to centuries. In contrast, the GWP provides radiative equivalence (in integrated terms) only at a single time, with large discrepancies at other times. Our approach also follows from consideration of greenhouse gas stabilisation, since stabilising atmospheric CO2 requires an approximate cap on total emissions, while stabilising methane requires stabilisation of ongoing emissions. Our quantitative treatment recognises that, on time scales of centuries, removal of 1 tonne of carbon only lowers the atmospheric carbon content by 0.3 to 0.35 tonnes. We discuss the implications for rangeland grazing systems. In the absence of effective mitigation techniques for methane from rangeland systems, this approach may provide an attractive offset mechanism in spite of requiring that woody vegetation be established and maintained over about 15% of the landscape, or an equivalent amount of carbon storage in soil.
Graphene-based THz modulator analyzed by equivalent circuit model
DEFF Research Database (Denmark)
Xiao, Binggang; Chen, Jing; Xie, Zhiyi;
2016-01-01
A terahertz (THz) modulator based on graphene is proposed and analysed by use of equivalent transmission line of a homogeneous mediumand the local anisotropic model of the graphene conductivity. The result calculated by the equivalent circuit is consistent with that obtained byFresnel transfer...... matrices. For the modulator proposed here, when the frequency of carrier wave is 0.6 THz, the theoretical analysis indicatesthat the modulation bandwidth is 55.5 kHz and the modulation depth is 81.3% for voltage change from 0 to 50 V...
The exponential-logarithmic equivalence classes of surreal numbers
Kuhlmann, Salma
2012-01-01
In his monograph, H. Gonshor showed that Conway's real closed field of surreal numbers carries an exponential and logarithmic map. Subsequently, L. van den Dries and P. Ehrlich showed that it is a model of the elementary theory of the field of real numbers with the exponential function. In this paper, we give a complete description of the exponential equivalence classes in the spirit of the classical Archimedean and multiplicative equivalence classes. This description is made in terms of a recursive formula as well as a sign sequence formula for the family of representatives of minimal length of these exponential classes.
Assessing equivalence of two assays using sensitivity and specificity.
Quiroz, Jorge; Burdick, Richard K
2007-01-01
The equivalence of two assays is determined using the sensitivity and specificity relative to a gold standard. The equivalence-testing criterion is based on a misclassification rate proposed by Burdick et al. (2005) and the intersection-union test (IUT) method proposed by Berger (1982). Using a variance components model and IUT methods, we construct bounds for the sensitivity and specificity relative to the gold standard assay based on generalized confidence intervals. We conduct a simulation study to assess whether the bounds maintain the stated test size. We present a computational example to demonstrate the method described in the paper.
The Galeazzi-equivalent lesion in children revisited.
Imatani, J; Hashizume, H; Nishida, K; Morito, Y; Inoue, H
1996-08-01
A fracture at the medial end of the distal third of the radius with an epiphyseal separation of the distal ulna in a 16-year-old boy is described. This injury, known as the Galeazzi-equivalent lesion in children, is characterized by complete distal ulnar epiphyseal separation without rupture of the distal ligamentous stabilizing system between the radius and ulna, which includes the triangular fibrocartilage complex, interosseous ligaments and periosteal tube of the ulnar. The Galeazzi fracture-dislocation and the Galeazzi-equivalent lesion appear to be completely dissimilar in their pathological anatomy. We suggest calling the latter a "pseudo-Galeazzi injury".
A weak equivalence principle test on a suborbital rocket
Reasenberg, Robert D
2010-01-01
We describe a Galilean test of the weak equivalence principle, to be conducted during the free fall portion of a sounding rocket flight. The test of a single pair of substances is aimed at a measurement uncertainty of sigma(eta) < 10^-16 after averaging the results of eight separate drops. The weak equivalence principle measurement is made with a set of four laser gauges that are expected to achieve 0.1 pm Hz^-1/2. The discovery of a violation (eta not equal to 0) would have profound implications for physics, astrophysics, and cosmology.
Equivalent Antisymmetry Performance of Three-Dimensional Heterogeneous Anisotropic Composites
Institute of Scientific and Technical Information of China (English)
李永; 宋健; 张志民
2003-01-01
Starting from the physical features of materials, heterogeneous anisotropic composites (HACs) are analysed on the basis of the understanding and applications of its equivalent antisymmetry performance. Moreover, the design parameter is optimized to attain the goal of maximizing the use of materials, which is quite meaningful. The HAC structure is defined as a kind of equivalent structures according to the structure and properties of materials.We apply the mature plate theory and the composite materials laminate theory in analysis of the HAC structure,and in this way a new concept and a new idea are expected.
Strip Waveguide Directional Coupling Modulator with Equivalent Refractive Index
Institute of Scientific and Technical Information of China (English)
LI Hong-tao; HE Dui-yan
2004-01-01
The equivalent refractive index(ERI) method is employed to analyze the function of the strip waveguide directional coupling modulator(SWM). Through deducing the diagnostic equation of the Exmn mode of the four-layer media film waveguide equivalent to the SWM,the transmission constant of the symmetrical mode of the positive phase and negative one and the coupling length of powerful transference are obtained. The veracity of ERI is validated with the example of Ex11 basal mode under the condition of comparing the three results of ERI,EIM and Marcatili.
Unitary equivalence to a truncated Toeplitz operator: analytic symbols
Garcia, Stephan Ramon; Ross, William T
2010-01-01
Unlike Toeplitz operators on $H^2$, truncated Toeplitz operators do not have a natural matricial characterization. Consequently, these operators are difficult to study numerically. In this note we provide criteria for a matrix with distinct eigenvalues to be unitarily equivalent to a truncated Toeplitz operator having an analytic symbol. This test is constructive and we illustrate it with several examples. As a byproduct, we also prove that every complex symmetric operator on a Hilbert space of dimension $\\leq 3$ is unitarily equivalent to a direct sum of truncated Toeplitz operators.
Equivalent circuit for postcoupler stabilization in a drift tube linac
Directory of Open Access Journals (Sweden)
Francesco Grespan
2012-01-01
Full Text Available Postcouplers (PCs are devices used in order to reduce the effect of perturbations on the operating mode of a drift tube linac (DTL, using the resonant coupling stabilization method. In this article an equivalent circuit for a DTL equipped with PCs is presented, together with a 3D simulation analysis, which can explain the principle of postcoupler stabilization and define a new tuning strategy for DTL cavities. The PC tuning procedure based on the equivalent circuit and on frequency measurements has been tested and validated with measurements on the Linac4 DTL aluminum model, present at CERN.
Chaotic memristive circuit: equivalent circuit realization and dynamical analysis
Institute of Scientific and Technical Information of China (English)
Bao Bo-Cheng; Xu Jian-Ping; Zhou Guo-Hua; Ma Zheng-Hua; Zou Ling
2011-01-01
In this paper,a practical equivalent circuit of an active flux-controlled memristor characterized by smooth piecewise-quadratic nonlinearity is designed and an experimental chaotic memristive circuit is implemented.The chaotic memristive circuit has an equilibrium set and its stability is dependent on the initial state of the memristor.The initial state-dependent and the circuit parameter-dependent dynamics of the chaotic memristive circuit are investigated via phase portraits,bifurcation diagrams and Lyapunov exponents.Both experimental and simulation results validate the proposed equivalent circuit realization of the active flux-controlled memristor.
Culturemes and Non-Equivalent Lexis in Dictionaries
Directory of Open Access Journals (Sweden)
Maciej Paweł Jaskot
2015-12-01
Full Text Available Culturemes and Non-Equivalent Lexis in Dictionaries The article raises the question of the need to improve the structural diversity and operational capabilities of the modern dictionary (bi- or multilingual to avoid lacunes in the transmission of culturemes and non-equivalent words into another language. Without it the dictionary is incomplete and languages are unequal. The article deals with various options of asymmetry reflection of the culturemes in the context of social and ethno-psychic reality of a native-speaking community. The specifics of lexicographical transmission is observed in order to emphasize the need of further investigation of the linguistic map of the world.
Equivalence of History and Generator Epsilon-Machines
Travers, Nicholas F
2011-01-01
Epsilon-machines are minimal, unifilar representations of stationary stochastic processes. They were originally defined in the history machine sense---as machines whose states are the equivalence classes of infinite histories with the same probability distribution over futures. In analyzing synchronization, though, an alternative generator definition was given: unifilar edge-label hidden Markov models with probabilistically distinct states. The key difference is that history epsilon-machines are defined by a process, whereas generator epsilon-machines define a process. We show here that these two definitions are equivalent.
The Extended Equivalence Principle and the Kramers-Kronig Relations
Chiao, R Y
2002-01-01
A seemingly obvious extension of the weak equivalence principle, in which all matter must respond to Post-Newtonian gravitational fields, such as Lense-Thirring and radiation fields, in a composition-independent way, is considered in light of the Kramers-Kronig dispersion relations for the linear response of any material medium to these fields. It is argued that known observational facts lead to violations of this extended form of the equivalence principle. (PACS numbers: 04.80.Cc, 04.80.Nn, 03.65.Ud, 67.40.Bz)
Equivalent sample theory of networked control systems and its application
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
The equivalent sample theory and its application in analysis of networked control system (NCS) are presented. After analyzing NCS's scheduling in master-slave mode, the characteristics of time delay and sample are summarized. Looking on master station visiting the slave station as a special sample process, the theory of equivalent sample is presented. And based on it, the stability of a kind of NCS is analyzed. The criterion to determine the upper bound of transmission delay is introduced, which guarantees the stability. Finally, an example with simulation shows the availability and usability of this analysis method.
Performance Evaluation of Full Search Equivalent Pattern Matching Algorithms.
Wanli Ouyang; Tombari, F; Mattoccia, S; Di Stefano, L; Wai-Kuen Cham
2012-01-01
Pattern matching is widely used in signal processing, computer vision, and image and video processing. Full search equivalent algorithms accelerate the pattern matching process and, in the meantime, yield exactly the same result as the full search. This paper proposes an analysis and comparison of state-of-the-art algorithms for full search equivalent pattern matching. Our intention is that the data sets and tests used in our evaluation will be a benchmark for testing future pattern matching algorithms, and that the analysis concerning state-of-the-art algorithms could inspire new fast algorithms. We also propose extensions of the evaluated algorithms and show that they outperform the original formulations.
Equivalent circuit for postcoupler stabilization in a drift tube linac
Grespan, Francesco
2012-01-01
Postcouplers (PCs) are devices used in order to reduce the effect of perturbations on the operating mode of a drift tube linac (DTL), using the resonant coupling stabilization method. In this article an equivalent circuit for a DTL equipped with PCs is presented, together with a 3D simulation analysis, which can explain the principle of postcoupler stabilization and define a new tuning strategy for DTL cavities. The PC tuning procedure based on the equivalent circuit and on frequency measurements has been tested and validated with measurements on the Linac4 DTL aluminum model, present at CERN.
NP-Logic Systems and Model-Equivalence Reductions
Shen, Yuping; 10.4204/EPTCS.24.17
2010-01-01
In this paper we investigate the existence of model-equivalence reduction between NP-logic systems which are logic systems with model existence problem in NP. It is shown that among all NP-systems with model checking problem in NP, the existentially quantified propositional logic (\\exists PF) is maximal with respect to poly-time model-equivalent reduction. However, \\exists PF seems not a maximal NP-system in general because there exits a NP-system with model checking problem D^P-complete.
Fuzzy logic systems are equivalent to feedforward neural networks
Institute of Scientific and Technical Information of China (English)
李洪兴
2000-01-01
Fuzzy logic systems and feedforward neural networks are equivalent in essence. First, interpolation representations of fuzzy logic systems are introduced and several important conclusions are given. Then three important kinds of neural networks are defined, i.e. linear neural networks, rectangle wave neural networks and nonlinear neural networks. Then it is proved that nonlinear neural networks can be represented by rectangle wave neural networks. Based on the results mentioned above, the equivalence between fuzzy logic systems and feedforward neural networks is proved, which will be very useful for theoretical research or applications on fuzzy logic systems or neural networks by means of combining fuzzy logic systems with neural networks.
New equivalent lumped electrical circuit for piezoelectric transformers.
Gonnard, Paul; Schmitt, P M; Brissaud, Michel
2006-04-01
A new equivalent circuit is proposed for a contour-vibration-mode piezoelectric transformer (PT). It is shown that the usual lumped equivalent circuit derived from the conventional Mason approach is not accurate. The proposed circuit, built on experimental measurements, makes an explicit difference between the elastic energies stored respectively on the primary and secondary parts. The experimental and theoretical resonance frequencies with the secondary in open or short circuit are in good agreement as well as the output "voltage-current" characteristic and the optimum efficiency working point. This circuit can be extended to various PT configurations and appears to be a useful tool for modeling electronic devices that integrate piezoelectric transformers.
Equivalences between Categories of Modules and Categories of Comodules
Institute of Scientific and Technical Information of China (English)
Joost VERCRUYSSE
2008-01-01
We show the close connection between apparently different Galois theories for comodules introduced recently in [J.Gómez-Torrecillas and J.Vercruysse,Comatrix corings and Galois Comodules over firm rings,Algebr.Represent.Theory,10 (2007),271-306]and [Wisbauer,On Galois comodules, Comm.Algebra 34 (2006),2683-2711].Furthermore we study equivalences between categories of comodules over a coring and modules over a firm ring.We show that these equivalences are related to Galois theory for comodules.
Equivalent Expressions of Direct Sum Decomposition of Groups1
Directory of Open Access Journals (Sweden)
Nakasho Kazuhisa
2015-03-01
Full Text Available In this article, the equivalent expressions of the direct sum decomposition of groups are mainly discussed. In the first section, we formalize the fact that the internal direct sum decomposition can be defined as normal subgroups and some of their properties. In the second section, we formalize an equivalent form of internal direct sum of commutative groups. In the last section, we formalize that the external direct sum leads an internal direct sum. We referred to [19], [18] [8] and [14] in the formalization.
The Public Market Equivalent and Private Equity Performance
DEFF Research Database (Denmark)
Sørensen, Morten; Jagannathan, Ravi
2015-01-01
betas due to changes in financial leverage, operating leverage, or the nature of the business are automatically taken into account; (2) the public market index used in evaluations should be the one that best approximates the wealth portfolio of the investor considering the PE investment opportunity.......The authors show that the public market equivalent approach is equivalent to assessing the performance of private equity (PE) investments using Rubinstein’s dynamic version of the CAPM. They developed two insights: (1) one need not compute betas of PE investments, and any changes in PE cash flow...
Braid equivalence in 3-manifolds with rational surgery description
Diamantis, Ioannis; Lambropoulou, Sofia
2013-01-01
In this paper we describe braid equivalence for knots and links in a 3-manifold $M$ obtained by rational surgery along a framed link in $S^3$. We first prove a sharpened version of the Reidemeister theorem for links in $M$. We then give geometric formulations of the braid equivalence via mixed braids in $S^3$ using the $L$-moves and the braid band moves. We finally give algebraic formulations in terms of the mixed braid groups $B_{m,n}$ using cabling and the techniques of parting and combing ...
Equivalent conductivity method: straightforward analytical solution for metasurface-based structures
DEFF Research Database (Denmark)
Danaeifar, Mohammad; Granpayeh, Nosrat; Mortensen, N. Asger;
2015-01-01
We present an equivalent conductivity method for analyzing metasurface-based structures, which relies on the derivation of equivalent conductivity containing the properties such as the geometry, periodicity, and the surrounding materials. Using this approach, one can calculate the equivalent...
Equivalent circuit models for ac impedance data analysis
Danford, M. D.
1990-01-01
A least-squares fitting routine has been developed for the analysis of ac impedance data. It has been determined that the checking of the derived equations for a particular circuit with a commercially available electronics circuit program is essential. As a result of the investigation described, three equivalent circuit models were selected for use in the analysis of ac impedance data.
Magnetodiode equivalent circuits for simulation of magnetic field sensors
Hotra, Zenon; Holyaka, Roman; Hladun, Michael
2003-09-01
The models for magnetic field sensors in SPICE software for circuit simulation are considered in this paper. The new approach for synthesis of magnetodiode equivalent circuits is presented. It is shown that using combination of physical and empirical models it is possible to maintain effective analysis of sensors in specialized software for circuit simulation.
School Principals' Leadership Skills: Measurement Equivalence across Cultures
Da'as, Rima'a
2017-01-01
Despite substantial interest and research in measuring leader's skills, little is known about the measurement equivalence and mean differences in the scores measuring principals' skills (cognitive, interpersonal, strategic) across cultures (collectivism versus individualism). The aim of the present study was to assess measurement…
Carbon footprint calculation model for the Mexican food equivalent system
Directory of Open Access Journals (Sweden)
Salvador Ruiz Cerrillo
2017-06-01
Full Text Available Introduction: the impact environment trough the anthropogenic action has been contributed to the fast production of greenhouse gases effect (GHG, a way to estimate the quantity of these substances is the carbon footprint (CF, nowadays it does not exist enough models for the calculation of food carbon footprint. Objective: the aim of this study was to design a calculation model for the measurement of the carbon footprint on the Mexican food equivalent system. Methods: it was about a retrospective study, a bibliographic review was made with original and review articles in different specialized researchers, there were included publications in English and Spanish, also published from 2000 to 2016. Results: a reference table was proposed for the food carbon footprint calculation on the Mexican food equivalent system trough the carbon intensity indicator, which is determined by the grams of emissions equivalents of carbon dioxide (CO2 in relation with the energetic contribution of each food equivalent. Conclusion: in a conclusion manner, estimating food carbon footprint is still a challenge, mean while the calculation models proposal is important to estimate the production of GHG trough a more sustainable food system.
Principles of Fidelity in Dynamic Equivalence Translation for Trainee Translators
Institute of Scientific and Technical Information of China (English)
刘屹
2011-01-01
For trainee translators,the question of to what extent equivalence can be achieved between the source text and the target text is always one of the most challenging parts to deal with.The paper tries to provide core principles of fidelity in dynamic equiv
A Concrete Representation of Observational Equivalence for PCF
Churchill, Martin; McCusker, Guy
2010-01-01
The full abstraction result for PCF using game semantics requires one to identify all innocent strategies that are innocently indistinguishable. This involves a quantification over all innocent tests, cf. quantification over all innocent contexts. Here we present a representation of innocent strategies that equates innocently indistinguishable ones, yielding a representation of PCF terms that equates precisely those terms that are observational equivalent.
Steganographic Capacity of Images, based on Image Equivalence Classes
DEFF Research Database (Denmark)
Hansen, Klaus; Hammer, Christian; Andersen, Jens Damgaard
2001-01-01
The problem of hiding information imperceptibly can be formulated as the problem of determining if a given image is a member of a sufficiently large equivalence class of images which to the Human Visual System appears to be the same image. This makes it possible to replace the given image with a ...
Equivalent Circuit Modeling of a Rotary Piezoelectric Motor
DEFF Research Database (Denmark)
El, Ghouti N.; Helbo, Jan
2000-01-01
In this paper, an enhanced equivalent circuit model of a rotary traveling wave piezoelectric ultrasonic motor "shinsei type USR60" is derived. The modeling is performed on the basis of an empirical approach combined with the electrical network method and some simplification assumptions about...
Equivalent dose determination using a quartz isothermal TL signal
DEFF Research Database (Denmark)
Vandenberghe, D.A.G.; Jain, Mayank; Murray, A.S.
2009-01-01
We report on further developments in the use of an isothermal thermoluminescence (ITL) signal for determining the equivalent dose (De) in unheated sedimentary quartz. In order to minimise sensitivity change during the first measurement, the ITL signal is measured at 270 °C following a preheat...
On Structuralism and Equivalence-oriented Approaches in Translation Studies
Institute of Scientific and Technical Information of China (English)
Li; Xuemin; Yin; Xiaorong
2014-01-01
The present paper is intended to examine the concept of equivalence in translation studies by presenting typical advocates and their influential statement,meanwhile,how structuralism influences in the studies is also investigated.The advantages and disadvantages are figured out,and further tendencies are stated.
On quantum equivalence of dual $\\sigma$ models $SL(3)$ examples
Horváth, Z; Palla, L
1996-01-01
The equivalence of several $SL(3)$ sigma models and their special Abelian duals is investigated in the two loop order of perturbation theory. The investigation is based on extracting and comparing various $\\beta$ functions of the original and dual models. The role of the discrete global symmetries is emphasized.
On quantum equivalence of dual sigma models: SL(3) examples
Energy Technology Data Exchange (ETDEWEB)
Horvath, Z. [Lorand Eoetvoes Univ., Budapest (Hungary). Inst. for Theoretical Physics; Karp, R.L. [Lorand Eoetvoes Univ., Budapest (Hungary). Inst. for Theoretical Physics; Palla, L. [Lorand Eoetvoes Univ., Budapest (Hungary). Inst. for Theoretical Physics
1997-04-14
The equivalence of several SL(3) sigma models and their special Abelian duals is investigated in two-loop order of perturbation theory. The investigation is based on extracting and comparing various {beta}-functions of the original and dual models. The role of discrete global symmetries is emphasized. (orig.).
Equivalent Circuit of a High Q Tunable PIFA
DEFF Research Database (Denmark)
Barrio, Samantha Caporal Del; Pelosi, Mauro; Franek, Ondrej
2011-01-01
This paper presents an Equivalent Circuit Model (ECM) for a high Quality factor (Q) tunable Planar Inverted F Antenna (PIFA). A PIFA is described and simulated with the Finite-Difference Time-Domain (FDTD) method. The resonance behavior of the proposed ECM is compared to the FDTD results and shows...
29 CFR 4.170 - Furnishing fringe benefits or equivalents.
2010-07-01
... required under the determination in order to satisfy his fringe benefit obligations under the Act, and must... fringe benefit obligations which may be required by an applicable fringe benefit determination, such as... 29 Labor 1 2010-07-01 2010-07-01 true Furnishing fringe benefits or equivalents. 4.170 Section...
Probing Students' Ideas of the Principle of Equivalence
Bandyopadhyay, Atanu; Kumar, Arvind
2011-01-01
The principle of equivalence was the first vital clue to Einstein in his extension of special relativity to general relativity, the modern theory of gravitation. In this paper we investigate in some detail students' understanding of this principle in a variety of contexts, when they are undergoing an introductory course on general relativity. The…
Entropic gravity, phase-space noncommutativity and the equivalence principle
Energy Technology Data Exchange (ETDEWEB)
Bastos, Catarina [Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Avenida Rovisco Pais 1, 1049-001 Lisboa (Portugal); Bertolami, Orfeu [Departamento de Fisica e Astronomia, Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto (Portugal); Dias, Nuno Costa; Prata, Joao Nuno, E-mail: catarina.bastos@ist.utl.pt, E-mail: orfeu.bertolami@fc.up.pt, E-mail: ncdias@meo.pt, E-mail: joao.prata@mail.telepac.pt [Departamento de Matematica, Universidade Lusofona de Humanidades e Tecnologias, Avenida Campo Grande, 376, 1749-024 Lisboa (Portugal)
2011-06-21
We generalize E Verlinde's entropic gravity reasoning to a phase-space noncommutativity setup. This allows us to impose a bound on the product of the noncommutative parameters based on the equivalence principle. The key feature of our analysis is an effective Planck's constant that naturally arises when accounting for the noncommutative features of the phase-space.
Maintaining Equivalent Cut Scores for Small Sample Test Forms
Dwyer, Andrew C.
2016-01-01
This study examines the effectiveness of three approaches for maintaining equivalent performance standards across test forms with small samples: (1) common-item equating, (2) resetting the standard, and (3) rescaling the standard. Rescaling the standard (i.e., applying common-item equating methodology to standard setting ratings to account for…
EQUIVALENT THEOREMS ON SIMULTANEOUS APPROXIMATION BY COMBINATIONS OF BERNSTEIN OPERATORES
Institute of Scientific and Technical Information of China (English)
Li Cheng; Linsen Xie
2006-01-01
In this paper we give equivalent theorems on simultaneous approximation for the combinations of Bernstein operators by r-th Ditzian-Totik modulus of smoothness ωτψλ (f, t)(0 ≤λ≤ 1). We also investigate the relation between the derivatives of the combinations of Bernstein operators and the smoothness of derivatives of functions.
One-to-One Play Promotes Numerical Equivalence Concepts
Mix, Kelly S.; Moore, Julie A.; Holcomb, Erin
2011-01-01
Young children spontaneously engage in a variety of one-to-one correspondence activities during play. The present study tested whether one of these activities--pairing objects with containers--supported the development of numerical equivalence judgments. Three-year-olds were given sets of toys to take home. In one condition, the toys were…
Multigroup Equivalence Analysis for High-Dimensional Expression Data
Yang, Celeste; Bartolucci, Alfred A.; Cui, Xiangqin
2015-01-01
Hypothesis tests of equivalence are typically known for their application in bioequivalence studies and acceptance sampling. Their application to gene expression data, in particular high-dimensional gene expression data, has only recently been studied. In this paper, we examine how two multigroup equivalence tests, the F-test and the range test, perform when applied to microarray expression data. We adapted these tests to a well-known equivalence criterion, the difference ratio. Our simulation results showed that both tests can achieve moderate power while controlling the type I error at nominal level for typical expression microarray studies with the benefit of easy-to-interpret equivalence limits. For the range of parameters simulated in this paper, the F-test is more powerful than the range test. However, for comparing three groups, their powers are similar. Finally, the two multigroup tests were applied to a prostate cancer microarray dataset to identify genes whose expression follows a prespecified trajectory across five prostate cancer stages. PMID:26628859
Multigroup Equivalence Analysis for High-Dimensional Expression Data.
Yang, Celeste; Bartolucci, Alfred A; Cui, Xiangqin
2015-01-01
Hypothesis tests of equivalence are typically known for their application in bioequivalence studies and acceptance sampling. Their application to gene expression data, in particular high-dimensional gene expression data, has only recently been studied. In this paper, we examine how two multigroup equivalence tests, the F-test and the range test, perform when applied to microarray expression data. We adapted these tests to a well-known equivalence criterion, the difference ratio. Our simulation results showed that both tests can achieve moderate power while controlling the type I error at nominal level for typical expression microarray studies with the benefit of easy-to-interpret equivalence limits. For the range of parameters simulated in this paper, the F-test is more powerful than the range test. However, for comparing three groups, their powers are similar. Finally, the two multigroup tests were applied to a prostate cancer microarray dataset to identify genes whose expression follows a prespecified trajectory across five prostate cancer stages.
The Analysis of Nida’s Functional Equivalence Theory
Institute of Scientific and Technical Information of China (English)
杨雪; 任培红
2014-01-01
Eugene A. Nida is an influential translation theoretician with great research achievements. The functional equivalence theory which is the core of his translation theories lays a solid foundation for the modern translation. However, there also exist some limitations in it. It should be dialectically analyzed to find its contributions and limitations.
Equivalence of Symptom Dimensions in Females and Males with Autism
Frazier, Thomas W.; Hardan, Antonio Y.
2017-01-01
This study investigated equivalence of autism symptom domains in males and females with autism. Symptom data were obtained from 2643 children and adolescents with autism spectrum disorder (352 females, 2291 males; age range = 4-17 years) included in the Simons Simplex Collection. Items from the Social Responsiveness Scale and Autism Diagnostic…
Observational Equivalence of Discrete String Models and Market Models
Kerkhof, F.L.J.; Pelsser, A.
2002-01-01
In this paper we show that, contrary to the claim made in Longsta, Santa-Clara, and Schwartz (2001a) and Longsta, Santa-Clara, and Schwartz (2001b), discrete string models are not more parsimonious than market models.In fact, they are found to be observationally equivalent.We derive that, for the es
Affine dual equivalence and k-Schur functions
Assaf, Sami
2012-01-01
The k-Schur functions were first introduced by Lapointe, Lascoux and Morse (2003) in the hopes of refining the expansion of Macdonald polynomials into Schur functions. Recently, an alternative definition for k-Schur functions was given by Lam, Lapointe, Morse, and Shimozono (2010) as the weighted generating function of starred strong tableaux which correspond with labeled saturated chains in the Bruhat order on the affine symmetric group modulo the symmetric group. This definition has been shown to correspond to the Schubert basis for the affine Grassmannian of type A by Lam (2008), and, at t = 1, it is equivalent to the k-tableaux characterization of Lapointe and Morse (2007). In this paper, we extend Haiman's (1992) dual equivalence relation on standard Young tableaux to all starred strong tableaux. The elementary equivalence relations can be interpreted as labeled edges in a graph which share many of the properties of Assaf's dual equivalence graphs. These graphs display much of the complexity of working w...
Entropic Gravity, Phase-Space Noncommutativity and the Equivalence Principle
Bastos, Catarina; Dias, Nuno Costa; Prata, João Nuno
2010-01-01
We generalize E. Verlinde's entropic gravity reasoning to a phase-space noncommutativity set-up. This allow us to impose a bound on the product of the noncommutative parameters based on the Equivalence Principle. The key feature of our analysis is an effective Planck's constant that naturally arises when accounting for the noncommutative features of the phase-space.
Section Preequating under the Equivalent Groups Design without IRT
Guo, Hongwen; Puhan, Gautam
2014-01-01
In this article, we introduce a section preequating (SPE) method (linear and nonlinear) under the randomly equivalent groups design. In this equating design, sections of Test X (a future new form) and another existing Test Y (an old form already on scale) are administered. The sections of Test X are equated to Test Y, after adjusting for the…
Equivalence of Translations in International Reading Literacy Studies
Arffman, Inga
2010-01-01
Recent years have witnessed a significant increase in the interest in international assessments of student performance. In such assessments it is mandatory that all the different-language texts be equivalent to each other, that is, equally difficult to understand. The article summarizes a study made on the topic, examining the problems of…
On the Applicability of the Surface Equivalence Theorem Inside Enclosures
DEFF Research Database (Denmark)
Franek, Ondrej; Sørensen, Morten; Ebert, Hans
2012-01-01
A scenario of a generic printed circuit board (PCB) representing an electronic module inside a metallic enclosure is studied numerically. Following the surface equivalence theorem, the PCB is replaced with surface currents running on a Huygens box (HB) inside the enclosure and near-field errors...
Barrier properties of human skin equivalents : rising to the surface
Thakoersing, Varsha Sakina
2012-01-01
Human skin equivalents (HSEs) are generated from isolated skin cells. As the primary function of the skin is to form a barrier, in this thesis the barrier properties of three HSEs were assessed and compared with native human skin. The results show that all HSEs have a decreased skin barrier function
State-Dependent Implication and Equivalence in Quantum Logic
Directory of Open Access Journals (Sweden)
Fedor Herbut
2012-01-01
Full Text Available Ideal occurrence of an event (projector leads to the known change of a state (density operator into (the Lüders state. It is shown that two events and give the same Lüders state if and only if the equivalence relation is valid. This relation determines equivalence classes. The set of them and each class, are studied in detail. It is proved that the range projector of the Lüders state can be evaluated as , where denotes the greatest lower bound, and is the null projector of . State-dependent implication extends absolute implication (which, in turn, determines the entire structure of quantum logic. and are investigated in a closely related way to mutual benefit. Inherent in the preorder is the state-dependent equivalence , defining equivalence classes in a given Boolean subalgebra. The quotient set, in which the classes are the elements, has itself a partially ordered structure, and so has each class. In a complete Boolean subalgebra, both structures are complete lattices. Physical meanings are discussed.
40 CFR 790.85 - Submission of equivalence data.
2010-07-01
... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Submission of equivalence data. 790.85 Section 790.85 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) PROCEDURES GOVERNING TESTING CONSENT AGREEMENTS AND TEST RULES Exemptions From...
Equivalent Circuit of a High Q Tunable PIFA
DEFF Research Database (Denmark)
Barrio, Samantha Caporal Del; Pelosi, Mauro; Franek, Ondrej
2011-01-01
This paper presents an Equivalent Circuit Model (ECM) for a high Quality factor (Q) tunable Planar Inverted F Antenna (PIFA). A PIFA is described and simulated with the Finite-Difference Time-Domain (FDTD) method. The resonance behavior of the proposed ECM is compared to the FDTD results and shows...
The Equivalence Forms of Random Kolmogorov Forward (Backward) Equations
Institute of Scientific and Technical Information of China (English)
HU Di-he; HU Xiao-yu
2005-01-01
The concepts of Markov process in random environment, q-matrix in random environment and q-process in random environment are introduced. Three forms of random Kolmoogrov farward (or backward) equations are introduced and the equivalence of these three forms are also proved. Moreover any conservative q-process in random environment satisfies random Kolmogrov backward equation.
Money for health : the equivalent variation of cardiovascular diseases
Groot, Willem; Van Den Brink, Henriëtte Maassen; Plug, Erik
2004-01-01
This paper introduces a new method to calculate the extent to which individuals are willing to trade money for improvements in their health status. An individual welfare function of income (WFI) is applied to calculate the equivalent income variation of health impairments. We believe that this appro