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Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 7166
Author(s):  
Alex Brenner ◽  
Tobias Hirsch ◽  
Marc Röger ◽  
Robert Pitz-Paal

The presented review gives reliable information about the currently used measurement instrumentation in parabolic trough fields and recent monitoring approaches. The usually built-in measurement equipment in the solar field, clamp-on systems for flexible measurements of temperature and flow, solar irradiance measurements, standard meteorological equipment, laboratory devices for heat transfer fluid analyses and instruments related to the tracking of solar collector assemblies are presented in detail. The measurement systems are reported with their measurement uncertainty, approximate costs and usual installation location for the built-in instrumentation. Specific findings related to the installation and operation of the measurement devices are presented. The usually installed instrumentation delivers a lot of measurements all over the field at the expense of measurement accuracy, compared to special test facility equipment. Recently introduced measurement approaches can improve the standard instrumentation in terms of accuracy, frequency, spatial distribution or can even extend the amount of measurands. The information about available measurands is the basis for future operation and maintenance solutions based on data-driven approaches.


Electricity ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 423-438
Author(s):  
Rodrigo D. Trevizan ◽  
Cody Ruben ◽  
Aquiles Rossoni ◽  
Surya C. Dhulipala ◽  
Arturo Bretas ◽  
...  

Simultaneous real-time monitoring of measurement and parameter gross errors poses a great challenge to distribution system state estimation due to usually low measurement redundancy. This paper presents a gross error analysis framework, employing μPMUs to decouple the error analysis of measurements and parameters. When a recent measurement scan from SCADA RTUs and smart meters is available, gross error analysis of measurements is performed as a post-processing step of non-linear DSSE (NLSE). In between scans of SCADA and AMI measurements, a linear state estimator (LSE) using μPMU measurements and linearized SCADA and AMI measurements is used to detect parameter data changes caused by the operation of Volt/Var controls. For every execution of the LSE, the variance of the unsynchronized measurements is updated according to the uncertainty introduced by load dynamics, which are modeled as an Ornstein–Uhlenbeck random process. The update of variance of unsynchronized measurements can avoid the wrong detection of errors and can model the trustworthiness of outdated or obsolete data. When new SCADA and AMI measurements arrive, the LSE provides added redundancy to the NLSE through synthetic measurements. The presented framework was tested on a 13-bus test system. Test results highlight that the LSE and NLSE processes successfully work together to analyze bad data for both measurements and parameters.


2021 ◽  
Vol 81 (10) ◽  
Author(s):  
D. W. P. Amaral ◽  
D. G. Cerdeño ◽  
A. Cheek ◽  
P. Foldenauer

AbstractThe recent measurement of the muon anomalous magnetic moment by the Fermilab E989 experiment, when combined with the previous result at BNL, has confirmed the tension with the SM prediction at $$4.2\,\sigma $$ 4.2 σ  CL, strengthening the motivation for new physics in the leptonic sector. Among the different particle physics models that could account for such an excess, a gauged $$U(1)_{L_\mu -L_{\tau }}$$ U ( 1 ) L μ - L τ stands out for its simplicity. In this article, we explore how the combination of data from different future probes can help identify the nature of the new physics behind the muon anomalous magnetic moment. In particular, we contrast $$U(1)_{L_\mu -L_{\tau }}$$ U ( 1 ) L μ - L τ with an effective $$U(1)_{L_\mu }$$ U ( 1 ) L μ -type model. We first show that muon fixed target experiments (such as NA64$$\mu $$ μ ) will be able to measure the coupling of the hidden photon to the muon sector in the region compatible with $$(g-2)_\mu $$ ( g - 2 ) μ , and will have some sensitivity to the hidden photon’s mass. We then study how experiments looking for coherent elastic neutrino-nucleus scattering (CE$$\nu $$ ν NS) at spallation sources will provide crucial additional information on the kinetic mixing of the hidden photon. When combined with NA64$$\mu $$ μ results, the exclusion limits (or reconstructed regions) of future CE$$\nu $$ ν NS detectors will also allow for a better measurement of the mediator mass. Finally, the observation of nuclear recoils from solar neutrinos in dark matter direct detection experiments will provide unique information about the coupling of the hidden photon to the tau sector. The signal expected for $$U(1)_{L_\mu -L_{\tau }}$$ U ( 1 ) L μ - L τ is larger than for $$U(1)_{L_\mu }$$ U ( 1 ) L μ with the same kinetic mixing, and future multi-ton liquid xenon proposals (such as DARWIN) have the potential to confirm the former over the latter. We determine the necessary exposure and energy threshold for a potential $$5\,\sigma $$ 5 σ discovery of a $$U(1)_{L_\mu -L_{\tau }}$$ U ( 1 ) L μ - L τ boson, and we conclude that the future DARWIN observatory will be able to carry out this measurement if the experimental threshold is lowered to $$1\,{\mathrm {keV}}_{\mathrm {nr}} $$ 1 keV nr .


Author(s):  
Manfred Daum ◽  
Peter-R. Kettle

The most precise value for the pion mass was determined from a precision measurement at PSI of the muon momentum in pion decay at rest, \pi^+ \rightarrow \mu^+ + \nu_{\mu}π+→μ++νμ. The result is m_{\pi^+} = 139.570\,21(14)mπ+=139.57021(14)~MeV/c^22. This value is more precise, however, in agreement with the recent compilation of the Particle Data Group for m_{\pi^-}mπ−. The agreement of m_{\pi^+}mπ+ with the recent measurement. This yields a new quantitative measure of CPT invariance in the pion sector: (m_{\pi^+} - m_{\pi^-})/m_{\pi}(\mbox{av}) = (-2.9 \pm 2.0)\cdot 10^{-6}(mπ+−mπ−)/mπ(av)=(−2.9±2.0)⋅10−6, an improvement by two orders of magnitude.


2021 ◽  
Vol 81 (8) ◽  
Author(s):  
Jakub Rembieliński ◽  
Paweł Caban ◽  
Jacek Ciborowski

AbstractWe performed a Lorentz covariant quantization of the spin-1/2 fermion field assuming the space-like energy-momentum dispersion relation. We achieved the task in the following steps: (i) determining the unitary realizations of the inhomogenous Lorentz group in the preferred frame scenario by means of the Wigner–Mackey induction procedure and constructing the Fock space; (ii) formulating the theory in a manifestly covariant way by constructing the field amplitudes according to the Weinberg method; (iii) obtaining the final constraints on the amplitudes by postulating a Dirac-like free field equation. Our theory allows to predict all chiral properties of the neutrinos, preserving the Standard Model dynamics. We discussed the form of the fundamental observables, energy and helicity, and show that non-observation of the $$+\tfrac{1}{2}$$ + 1 2 helicity state of the neutrino and the $$-\tfrac{1}{2}$$ - 1 2 helicity state of the antineutrino could be a direct consequence of the “tachyoneity” of neutrinos at the free level. We found that the free field theory of the space-like neutrino is not invariant under the C and P transformations separately but is CP-invariant. We calculated and analyzed the electron energy spectrum in tritium decay within the framework of our theory and found an excellent agreement with the recent measurement of KATRIN. In our formalism the questions of negative/imaginary energies and the causality problem does not appear.


2021 ◽  
Author(s):  
Dmitri Ivanov ◽  
D. Bergman ◽  
G. Furlich ◽  
R. Gonzalez ◽  
G. Thomson ◽  
...  

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Marcelo Lopes ◽  
Angelo Karaboyas ◽  
David W Johnson ◽  
Talerngsak Kanjanabuch ◽  
Martin Wilkie ◽  
...  

Abstract Background and Aims While it has been established that high serum phosphorus is associated with mortality in hemodialysis (HD) patients, there is limited evidence in the peritoneal dialysis (PD) setting. We evaluated the association of serum phosphorus with mortality and major adverse cardiovascular events (MACE) in patients on PD, and investigated various parameterizations using single and serial measurements of serum phosphorus. Method We utilized data from 7 countries in phase 1 (2014-2017) of the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS): Australia, Canada, Japan, New Zealand, Thailand, the UK, and the US. We investigated the association of serum phosphorus and 3 outcomes: all-cause mortality, cardiovascular (CV) mortality, and MACE (CV mortality + non-fatal angina, myocardial infarction, stroke, and heart failure). We parameterized serum phosphorus using 4 different methods: (1) single measurement of baseline serum phosphorus [most recent measurement during 6-month run-in period]; (2) mean serum phosphorus over a 6-month run-in period; (3) number of months (over the past 6 months) with serum phosphorus above the target range (>4.5 mg/dL); (4) mean area-under-the-curve (AUC), calculated as the average amount of time spent with serum phosphorus >4.5 mg/dL multiplied by the extent to which this threshold was exceeded over 6 months. Cox regression was used to estimate the association between each of these 4 exposures with the time-to-event outcomes, in models thoroughly adjusted for possible confounders. Follow-up began after the 6-month run-in period and continued until the outcome occurred, 7 days after leaving the facility due to transfer or change in kidney replacement therapy modality, loss to follow-up, or end of study phase (whichever event occurred first). Results Our sample consisted of 5904 patients who were on PD. Those with higher serum phosphorus levels were younger and had lower hemoglobin levels. Compared to patients with serum phosphorus ≥3.5 to <4.5 mg/dL, we found an all-cause mortality hazard ratio (HR) of 1.62 (95% CI: 1.19, 2.20) for patients with serum phosphorus ≥ 7 mg/dL. Strong associations were also observed using serial phosphorus measures [Table]. For example, compared to the reference group of AUC=0, the HR (95% CI) of death was 1.49 (1.10, 2.00) for AUC >1 to 2; and 1.67 (1.15, 2.41) for AUC >2. Akaike Information Criteria (AIC) results showed that, among the 4 exposures, AUC was the strongest predictor of all-cause mortality, and the single phosphorus measure was the weakest predictor. Associations between serum phosphorus and adverse outcomes were generally stronger for CV death and MACE than for all-cause mortality [Table]. Conclusion As seen in HD patients, this analysis demonstrates that serum phosphorus is a strong predictor of adverse outcomes in patients on PD. When considering serial measurements of serum phosphorus, rates of adverse events began to rise at phosphorus levels >4.5 mg/dL. As recommended by KDIGO guidelines, serial measurements that consider a history of serum phosphorus excursions >4.5 mg/dL should be considered when assessing risks of adverse outcomes.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Victor Tkachenko ◽  
Vladimir Lipp ◽  
Martin Büscher ◽  
Flavio Capotondi ◽  
Hauke Höppner ◽  
...  

AbstractSpatially encoded measurements of transient optical transmissivity became a standard tool for temporal diagnostics of free-electron-laser (FEL) pulses, as well as for the arrival time measurements in X-ray pump and optical probe experiments. The modern experimental techniques can measure changes in optical coefficients with a temporal resolution better than 10 fs. This, in an ideal case, would imply a similar resolution for the temporal pulse properties and the arrival time jitter between the FEL and optical laser pulses. However, carrier transport within the material and out of its surface, as well as carrier recombination may, in addition, significantly decrease the number of carriers. This would strongly affect the transient optical properties, making the diagnostic measurement inaccurate. Below we analyze in detail the effects of those processes on the optical properties of XUV and soft X-ray irradiated Si$${_3}$$ 3 N$$_4$$ 4 , on sub-picosecond timescales. Si$${_3}$$ 3 N$$_4$$ 4 is a wide-gap insulating material widely used for FEL pulse diagnostics. Theoretical predictions are compared with the published results of two experiments at FERMI and LCLS facilities, and with our own recent measurement. The comparison indicates that three body Auger recombination strongly affects the optical response of Si$${_3}$$ 3 N$$_4$$ 4 after its collisional ionization stops. By deconvolving the contribution of Auger recombination, in future applications one could regain a high temporal resolution for the reconstruction of the FEL pulse properties measured with a Si$${_3}$$ 3 N$$_4$$ 4 -based diagnostics tool.


2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
Yiannis Makris ◽  
Felix Ringer ◽  
Wouter J. Waalewijn

Abstract We present the framework for obtaining precise predictions for the transverse momentum of hadrons with respect to the thrust axis in e+e− collisions. This will enable a precise extraction of transverse momentum dependent (TMD) fragmentation functions from a recent measurement by the Belle Collaboration. Our analysis takes into account, for the first time, the nontrivial interplay between the hadron transverse momentum and the cut on the thrust event shape. To this end, we identify three different kinematic regions, derive the corresponding factorization theorems within Soft Collinear Effective Theory, and present all ingredients needed for the joint resummation of the transverse momentum and thrust spectrum at NNLL accuracy. One kinematic region can give rise to non-global logarithms (NGLs), and we describe how to include the leading NGLs. We also discuss alternative measurements in e+e− collisions that can be used to access the TMD fragmentation function. Finally, by using crossing symmetry, we obtain a new way to constrain TMD parton distributions, by measuring the displacement of the thrust axis in ep collisions.


2021 ◽  
Vol 256 ◽  
pp. 00002
Author(s):  
A. Al-Adili ◽  
Z. Gao ◽  
M. Lantz ◽  
A. Solders ◽  
M. Österlund ◽  
...  

The generation of angular momentum in the fission process is still an open question. To shed light on this topic, we started a series of measurements at the IGISOL-JYFLTRAP facility in Finland. Highprecision measurements of isomeric yield ratios (IYR) are performed with a Penning trap, partly with the aim to extract average root-mean-square (rms) quantities of fragment spin distributions. The newly installed Phase-Imaging Ion-Cyclotron Resonance (PI-ICR) technique allows the separation of masses down to tens of keV, which is suffcient to disentangle many isomers. In this paper, we first summarize the previous measurements on the neutron and proton-induced fission of uranium and thorium, e.g. the odd cadmium and indium isotopes (119 ≤ A ≤ 127). The measurements revealed systematic trends as function of mass number, which stimulated further exploration. A recent measurement was performed at IGISIOL and several new IYR data will soon be published, for the first time. Secondly, we employ the TALYS nuclear-reaction code to model one of the newly measured isomer yields. Detailed GEF and TALYS calculations are discussed for the fragment angular momentum distribution in 134I.


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