“Two Truths and a Lie” as a Class-Participation Activity

An approach to a statistical calibration of active power, reactive power and voltage measurements is shown. Measurement errors are studied according to their nature: systematic, installation and random errors. Effect of installation and systematic measurement errors on an energy management system (EMS) is analysed, paying special attention to its effect in state estimator behaviour. State estimator accuracy is discussed in order to analyse its use as a measurement standard. Statistical calibration is deeply explained: series of measured and estimated data are statistically processed getting valuable information regarding each measurement. This information is further analysed in order to remotely calibrate those measurements with systematic and installation errors, along with the determination of unknown state estimator measurement weights. The paper shows that once measurements have been statistically calibrated, immediate replacement of outdated equipment can be avoided, and furthermore, measurement errors can be dealt with as pure random errors (normally distributed).

Unification theory of classical statistical uncertainty relation and quantum uncertainty relation and its applications

A prominent formulation of the uncertainty principle identifies the fundamental quantum feature that no particle may be prepared with certain outcomes for both position and momentum measurements. Often the statistical uncertainties are thereby measured in terms of entropies providing a clear operational interpretation in information theory and cryptography. Recently, entropic uncertainty relations have been used to show that the uncertainty can be reduced in the presence of entanglement and to prove security of quantum cryptographic tasks. However, much of this recent progress has been focused on observables with only a finite number of outcomes not including Heisenberg’s original setting of position and momentum observables. Here, we show entropic uncertainty relations for general observables with discrete but infinite or continuous spectrum that take into account the power of an entangled observer. As an illustration, we evaluate the uncertainty relations for position and momentum measurements, which is operationally significant in that it implies security of a quantum key distribution scheme based on homodyne detection of squeezed Gaussian states.

The interpretation of the uncertainty principle in terms of a measurement of a single observable disturbing other observables, originating in Heisenberg's 1927 paper, is shown to be derivable from an uncertainty principle for joint measurements of incompatible observables. The latter also limits measurements of a single observable in the presence of conservation laws.

Flow rate measurements are a common topic for process monitoring in chemical engineering and food industry. To achieve the requested low uncertainties of 0:1% for flow rate measurements, a precise measurement of the shear layers of such flows is necessary. The Laser Doppler Velocimeter (LDV) is an established method for measuring local flow velocities. For exact estimation of the flow rate, the flow profile in the shear layer is of importance. For standard LDV the axial resolution and therefore the number of measurement points in the shear layer is defined by the length of the measurement volume. A decrease of this length is accompanied by a larger fringe distance variation along the measurement axis which results in a rise of the measurement uncertainty for the flow velocity (uncertainty relation between spatial resolution and velocity uncertainty). As a unique advantage, the laser Doppler profile sensor (LDV-PS) overcomes this problem by using two fan-like fringe systems to obtain the position of the measured particles along the measurement axis and therefore achieve a high spatial resolution while it still offers a low velocity uncertainty. With this technique, the flow rate can be estimated with one order of magnitude lower uncertainty, down to 0:05% statistical uncertainty. 1 And flow profiles especially in film flows can be measured more accurately. The problem for this technique is, in contrast to laboratory setups where the system is quite stable, that for industrial applications the sensor needs a reliable and robust traceability to the SI units, meter and second. Small deviations in the calibration can, because of the highly position depending calibration function, cause large systematic errors in the measurement result. Therefore, a simple, stable and accurate tool is needed, that can easily be used in industrial surroundings to check or recalibrate the sensor. In this work, different calibration methods are presented and their influences to the measurement uncertainty budget of the sensor is discussed. Finally, generated measurement results for the film flow of an impinging jet cleaning experiment are presented.

So that students can acquire a conceptual understanding of basic statistical concepts, the orientation of the introductory statistics course must change from a lecture-and-listen format to one that engages students in active learning. This is the premise underlying an effort of the authors to produce and use a collection of hands-on activities that illustrate the basic concepts of statistics covered in most introductory college courses. Such activities promote the teaching of statistics more as an experimental science and less as a traditional course in mathematics. An activity-based approach enhances learning by improving the students' attention, motivation, and understanding. This paper presents examples of the types of activities that work well in various classroom settings along with comments from colleagues and students on their effectiveness.

Attention-Deficit Hyperactive Disorder (ADHD) is a widely spread phenomenon affecting learning abilities and performance. The aim of the research is to test the mechanism linking ADHD with statistics test performance. We found a significant indirect path linking the ADHD diagnosis and the final grade. ADHD was linked to lower self-efficacy, leading to a more negative attitude towards statistics and lower grades. While treating ADHD is beyond the ability of a course lecturer, its adverse consequences such as impaired performance, can be addressed in the classroom setting. Lecturers should be encouraged to take steps towards increasing the self-efficacy and positive perception of statistics of their students. This may help improve the performance of students with ADHD without having to directly treat the disorder.

Uncertainty relations are derived for fluorescence caused by laser excitation in flames. The effect of statistical and systematic uncertainties on the detectability limits for excited states are examined. Fluorescence trapping is discussed and shown to establish an upper limit on the number density that can be measured. Methods for minimizing the trapping effect are discussed.

Nonlinear, discrete flood event models, 1. Bayesian estimation of parameters

The Action Uncertainty Principle for Continuous Quantum Measurements

The material contained in this paper focuses on using 3D printing of relatively simple, flexible structural components and plane frames. The relatively high resolution of modern 3D printers facilitates the production of slender structures, and thus provides an opportunity to exploit geometric parameter variations to enhance a practical understanding of stiffness and vibration. This approach has proved successful in initial inclusion in both the classroom via demonstration models, as well as in the lab in which elementary facilities can be utilized to acquire data. An especially useful facet of this approach is the assessment and justification for modeling simplifications, e.g., judging the circumstances under which the familiar sway assumption is valid in portal frames. Furthermore, minor parametric variations can be easily incorporated into sensitivity studies, and the production of multiple copies of essentially the same geometry promotes an effective use of statistical measurement uncertainty. We then extend this approach to forced vibration, with examples including the vibrating reed tachometer and sympathetic resonance.The material contained in this paper focuses on using 3D printing of relatively simple, flexible structural components and plane frames. The relatively high resolution of modern 3D printers facilitates the production of slender structures, and thus provides an opportunity to exploit geometric parameter variations to enhance a practical understanding of stiffness and vibration. This approach has proved successful in initial inclusion in both the classroom via demonstration models, as well as in the lab in which elementary facilities can be utilized to acquire data. An especially useful facet of this approach is the assessment and justification for modeling simplifications, e.g., judging the circumstances under which the familiar sway assumption is valid in portal frames. Furthermore, minor parametric variations can be easily incorporated into sensitivity studies, and the production of multiple copies of essentially the same geometry promotes an effective use of statistical measurement uncertainty. We then ...

Impact of unresolved smaller scales on the scalar dissipation rate in direct numerical simulations of wall bounded flows

We present new light curves for the four bright images of the five image cluster-lensed quasar gravitational lens system SDSS J1004+4112. The light curves span 14.5 yr and allow the measurement of the time delay between the trailing bright quasar image D and the leading image C. When we fit all four light curves simultaneously and combine the models using the Bayesian information criterion, we find a time delay of Δt DC = 2458.47 ± 1.02 days (6.73 yr), the longest ever measured for a gravitational lens. For the other two independent time delays we obtain Δt BC = 782.20 ± 0.43 days (2.14 yr) and Δt AC = 825.23 ± 0.46 days (2.26 yr), in agreement with previous results. The information criterion is needed to weight the results for light curve models with different polynomial orders for the intrinsic variability and the effects of differential microlensing. The results using the Akaike information criterion are slightly different, but, in practice, the absolute delay errors are all dominated by the ∼4% cosmic variance in the delays rather than the statistical or systematic measurement uncertainties. Despite the lens being a cluster, the quasar images show slow differential variability due to microlensing at the level of a few tenths of a magnitude.

The Wyoming Survey for H-alpha, or WySH, is a large-area, ground-based imaging survey for H-alpha-emitting galaxies at redshifts of z ~ 0.16, 0.24, 0.32, and 0.40. The survey spans up to four square degrees in a set of fields of low Galactic cirrus emission, using twin narrowband filters at each epoch for improved stellar continuum subtraction. H-alpha luminosity functions are presented for each Delta(z) ~ 0.02 epoch based on a total of nearly 1200 galaxies. These data clearly show an evolution with lookback time in the volume-averaged cosmic star formation rate. Integrals of Schechter fits to the incompleteness- and extinction-corrected H-alpha luminosity functions indicate star formation rates per co-moving volume of 0.010, 0.013, 0.020, 0.022 h_70 M_sun yr^{-1} Mpc^{-3} at z ~ 0.16, 0.24, 0.32, and 0.40, respectively. Statistical and systematic measurement uncertainties combined are on the order of 25% while the effects of cosmic variance are at the 20% level. The bulk of this evolution is driven by changes in the characteristic luminosity L_* of the H-alpha luminosity functions, with L_* for the earlier two epochs being a factor of two larger than L_* at the latter two epochs; it is more difficult with this data set to decipher systematic evolutionary differences in the luminosity function amplitude and faint-end slope. Coupling these results with a comprehensive compilation of results from the literature on emission line surveys, the evolution in the cosmic star formation rate density over 0 < z < 1.5 is measured to be rho_dot_SFR(z) = rho_dot_SFR(0) (1+z)^{3.4+/-0.4}.

Italian strong-motion data were used to study attenuation characteristics of horizontal peak ground acceleration and velocity. The data base consisted of 190 horizontal components of accelerograms recorded in Italy since 1976 from 17 earthquakes of magnitudes 4.6 to 6.8. The resulting equations are log A = − 1.562 + 0.306 M − log ( R 2 + 5.8 2 ) 1 / 2 + 0.169 S log V = − 0.710 + 0.455 M − log ( R 2 + 3.6 2 ) 1 / 2 + 0.133 S where A is peak horizontal acceleration in g , V is peak horizontal velocity in centimeters/second, M is magnitude, R is the closest distance to the surface projection of the fault rupture in kilometers, and S is a variable taking the values of 0 and 1 according to the local site geology. Peak acceleration and velocity were found to be lognormally distributed with a standard error representing, respectively, a 49 and 64 per cent increase in the median estimate. We considered a magnitude-dependent shape of the attenuation curves, but we found no basis for it in the data. Attenuation relationships developed using epicentral distance in place of fault distance gave similar results, with higher standard errors and higher predicted values for short distances and high magnitudes. Sensitivity studies, performed with the analysis of the residuals, showed that predictions based on our relatiaons are stable with respect to reasonable variations of the model and the seismic areas providing the data. Comparisons with attenuation relationships proposed for western North America showed differences of the same order of magnitude as the statistical prediction uncertainty.