208 research outputs found
Autoencoder Application for Anomaly Detection in Power Consumption of Lighting Systems
No full textDetecting energy consumption anomalies is a popular topic of industrial research, but there is a noticeable lack of research reported in the literature on energy consumption anomalies for road lighting systems. However, there is a need for such research because the lighting system, a key element of the Smart City concept, creates new monitoring opportunities and challenges. This paper examines algorithms based on the deep learning method using the Autoencoder model with LSTM and 1D Convolutional networks for various configurations and training periods. The evaluation of the algorithms was carried out based on real data from an extensive lighting control system. A practical approach was proposed using real-time, unsupervised algorithms employing limited computing resources that can be implemented in industrial devices designed to control intelligent city lighting. An anomaly detection algorithm based on classic LSTM networks, single-layer and multi-layer, was used for comparison purposes. Error matrix calculus was used to assess the quality of the models. It was shown that based on the Autoencoder method, it is possible to construct an algorithm that correctly detects anomalies in power measurements of lighting systems, and it is possible to build a model so that the algorithm works correctly regardless of the season of the year
Enhancing the CO2 Electroreduction of Fe/Ni-Pentlandite Catalysts by S/Se Exchange
No full text99389944The electrochemical reduction of CO2 is an attractive strategy towards the mitigation of environmental pollution and production of bulk chemicals as well as fuels by renewables. The bimetallic sulfide Fe4.5Ni4.5S8 (pentlandite) was recently reported as a cheap and robust catalyst for electrochemical water splitting, as well as for CO2 reduction with a solvent‐dependent product selectivity. Inspired by numerous reports on monometallic sulfoselenides and selenides revealing higher catalytic activity for the CO2 reduction reaction (CO2RR) than their sulfide counterparts, the authors investigated the influence of stepwise S/Se exchange in seleno‐pentlandites Fe4.5Ni4.5S8‐YSeY (Y=1-5) and their ability to act as CO2 reducing catalysts. It is demonstrated that the incorporation of higher equivalents of selenium favors the CO2RR with Fe4.5Ni4.5S4Se4 revealing the highest activity for CO formation. Under galvanostatic conditions in acetonitrile, Fe4.5Ni4.5S4Se4 generates CO with a Faradaic Efficiency close to 100 % at applied current densities of −50 mA cm−2 and −100 mA cm−2. This work offers insight into the tunability of the pentlandite based electrocatalysts for the CO2 reduction reaction.264
Development of Intelligent Road Signs with V2X Interface for Adaptive Traffic Controlling
No full textEvidence for a mixed mass composition at the ‘ankle’ in the cosmic-ray spectrum
No full textWe report a first measurement for ultrahigh energy cosmic rays of the correlation between the depth of shower maximum and the signal in the water Cherenkov stations of air-showers registered simultaneously by the fluorescence and the surface detectors of the Pierre Auger Observatory. Such a correlation measurement is a unique feature of a hybrid air-shower observatory with sensitivity to both the electromagnetic and muonic components. It allows an accurate determination of the spread of primary masses in the cosmic-ray flux. Up till now, constraints on the spread of primary masses have been dominated by systematic uncertainties. The present correlation measurement is not affected by systematics in the measurement of the depth of shower maximum or the signal in the water Cherenkov stations. The analysis relies on general characteristics of air showers and is thus robust also with respect to uncertainties in hadronic event generators. The observed correlation in the energy range around the ‘ankle’ at lg(E/eV)=18.5–19.0lg(E/eV)=18.5–19.0 differs significantly from expectations for pure primary cosmic-ray compositions. A light composition made up of proton and helium only is equally inconsistent with observations. The data are explained well by a mixed composition including nuclei with mass A>4A>4. Scenarios such as the proton dip model, with almost pure compositions, are thus disfavored as the sole explanation of the ultrahigh-energy cosmic-ray flux at Earth
Synthesis, properties and catalytic performance of the novel, pseudo-spinel, multicomponent transition-metal selenides
No full text53375349With electrocatalysis being the very foundation of multiple energy conversion technologies, the search for more effective, and affordable catalysts is becoming increasingly important for their further development. Recently, the multicomponent approach, together with the electronic structure calculations, have established themselves as promising ways of designing such materials. In the presented study, both these approaches are combined, leading to the development of a unprecedented (Co,Fe,Ni)3Se4 chalcogenide catalyst. Based on the extensive density functional theory calculations (DFT), and structural data, the impact of the multi-element atomic arrangement is discussed, and the possible benefits of such a design strategy are identified. The transport and catalytic properties of the materials are studied, showing excellent charge transfer capabilities, combined with very high catalytic activity with regard to the hydrogen evolution reaction (HER), as evidenced by the current densities of 120, 500, and 1000 mA cm-2 at overpotentials of 250, 360, and 450 mV. Of importance, all these results are achieved for the bulk-type electrode, obtained by a simple and scalable process, a considerable advantage over most of the state-of-the-art electrocatalysts, requiring costly and time-consuming nano-structuring of the electrode layer.20231
pentlandite solid electrodes
No full text75267538The multi-component approach to materials design is gaining increasing popularity in energy-conversion-oriented applications. This study describes a 5-component multimetallic chalcogenide compound with a pentlandite structure that recently became increasingly interesting in terms of electrocatalytic water splitting. The solubility limit of Se in the trimetallic Co3Fe3Ni3S8 system was determined along with the potential effect of this additive on the material's intrinsic properties. This was followed by an unprecedented approach, an attempt to fabricate solid electrodes using the inductive hot-pressing method. The effects of the consolidation conditions on the morphology and final properties of the material are discussed in detail. Tailoring both the chemical composition and processing conditions (initial grain size, sintering temperature) can lead to the optimization of highly efficient electrocatalysts for water splitting. The best electrodes were characterized at elevated current densities of 120 mA cm-2, showing low overpotentials (240 mV versus RHE) but with rather low electrochemical active surface area and moderately optimal reaction kinetics. It was therefore shown that using multi-component compositions resulted in good intrinsic properties of the materials toward hydrogen production, together with high density and vacancy concentrations provided by the sintering process, thus producing an efficient electrocatalyst using a simple, scalable method without any additional processing.111
Erratum: Search for photons with energies above 1018 eV using the hybrid detector of the Pierre Auger Observatory (Journal of Cosmology and Astroparticle Physics (2017) 4 (9) DOI: 10.1088/1475-7516/2017/04/009)
No full text1 Exposure calculation Due to a mistake in the numerical integration following eq. (6.2) of the original article [1], the exposure shown in figure 5 of the original article was incorrect. The correct exposure is shown in figure 1. 2 Upper limits on the integral photon flux and fraction The incorrect exposure affects the calculation of the upper limits on the integral photon flux following eq. (6.1) of the original article. The correct values for the upper limits are 0.038, 0.010, 0.009, 0.008 and 0.007 km−2 sr−1 yr−1 for threshold energies of 1, 2, 3, 5 and 10 EeV. The correct values for the upper limits on the integral photon fraction subsequently derived are 0.14 %, 0.17 %, 0.42 %, 0.86 % and 2.9 % for the same threshold energies. 3 Author list The author list of this erratum also corrects a mistake made in the original article, where F. Zuccarello was missing and Z. Zong was listed twice
Compatibility Studies of a Soluble T4 Receptor with a Microinfusion Pump for Continuous Intravenous Therapy
No full textTuning the Electrocatalytic Properties of Trimetallic Pentlandites: Stability and Catalytic Activity as a Function of Material Form and Selenium Concentration
No full textPentlandites are one possible cost-effective alternative
to platinum
group metals for green hydrogen production. This study delves into
the catalytic performance of trimetallic pentlandite systems, exploring
the influence of selenium concentration and material form on their
efficiency by combining the investigation of materials in various
forms (powder catalysts, ingots, and highly densified pellets) with
a computational investigation. The experimentally observed solubility
limit of selenium was clarified based on the formation energies approach.
The best and most stable defect combination, namely, Se:S substitution
and S vacancy, was identified and correlated with improved catalytic
properties of the systems with small Se addition. Further findings
highlight the evolving importance of intrinsic material properties,
such as bond properties, intermetallic interactions, or electronic
structure, over surface effects, including the activation process,
as the material density increases. The research contributes valuable
insight into the intricate mechanisms governing pentlandite catalysis.
Understanding these dynamics allows for intentional modifications,
advancing the application of pentlandites in hydrogen production
Structure And Internal Motions Of The Propargyl Alcohol-water Complex
No full textThe rotational spectra of the propargyl alcohol (PA)–water complex has been studied using a pulsed nozzle Fourier transform microwave spectrometer. PA is multifunctional molecule having a hydroxyl group and an acetylenic moiety. We have observed a cyclic hydrogen bonded structure. The alcohol donates an H-bond to water and the acetylenic moiety accepts a weak O-H- H-bond from water. Calculations show that the two lowest energy structures have this same structural motif and differ only in the position of the non-bonded H atom of water. Several isotopic substitutions were carried out to ascertain the position of the non-bonded hydrogen of HO. Rotational spectroscopy helps to differentiate between these two similar structures. Splitting of the rotational transitions was also observed, indicating the presence of internal motions of the HO fragment. The observed global minimum structure is compared with earlier results from IR spectroscopy in matrix\footnote{Saini, J.; Viswanathan, K. S. J. Mol. Struct. 2016, 1118, 147–156.} and helium nanodroplet\footnote{Mani, D.; Pal, N.; Smialkowski, M.; Beakovic, C.; Schwaab, G.; Havenith, M. Phys. Chem. Chem. Phys. 2019, 21, 20582–20587.}. We also compare the global minima of several alcohol-water complexes to understand the donor-acceptor capabilities of the OH groups in alcohol-water complexes.Made available in DSpace on 2021-09-24T21:09:15Z (GMT). No. of bitstreams: 2
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