Towards operational multi-GNSS tropospheric products at GFZ Potsdam

The assimilation of global navigation satellite system (GNSS) data has been proven to have a positive impact on weather forecasts. However, the impact is limited due to the fact that solely the zenith total delays (ZTDs) or integrated water vapor (IWV) derived from the GPS satellite constellation are utilized. Assimilation of more advanced products, such as slant total delays (STDs), from several satellite systems may lead to improved forecasts. This study shows a preparation step for the assimilation, i.e., the analysis of the multi-GNSS tropospheric advanced parameters: ZTDs, tropospheric gradients and STDs. Three solutions are taken into consideration: GPS-only, GPS–GLONASS (GR) and GPS–GLONASS–Galileo (GRE). The GNSS estimates are calculated using the operational EPOS.P8 software developed at GFZ. The ZTDs retrieved with this software are currently being operationally assimilated by weather services, while the STDs and tropospheric gradients are being tested for this purpose. The obtained parameters are compared with the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 reanalysis. The results show that all three GNSS solutions show similar level of agreement with the ERA5 model. For ZTDs, the agreement with ERA5 results in biases of approx. 2 mm and standard deviations (SDs) of 8.5 mm. The statistics are slightly better for the GRE solution compared to the other solutions. For tropospheric gradients, the biases are negligible, and SDs are equal to approx. 0.4 mm. The statistics are almost identical for all three GNSS solutions. For STDs, the agreement from all three solutions is very similar; however it is slightly better for GPS only. The average bias with respect to ERA5 equals approx. 4 mm, with SDs of approx. 26 mm. The biases are only slightly reduced for the Galileo-only estimates from the GRE solution. This study shows that all systems provide data of comparable quality. However, the advantage of combining several GNSS systems in the operational data assimilation is the geometry improvement by adding more observations, especially for low elevation and azimuth angles.

Combining Polygon Schematization and Decomposition Approaches for Solving the Cavity Decomposition Problem

The cavity decomposition problem is a computational geometry problem, arising in the context of modern electronic CAD systems, that concerns detecting the generation and propagation of electromagnetic noise into multi-layer printed circuit boards. Algorithmically speaking, the problem can be formulated so as to contain, as sub-problems, the well-known polygon schematization and polygon decomposition problems. Given a polygon P and a finite set C of given directions, polygon schematization asks for computing a C -oriented polygon P ′ with “low complexity” and “high resemblance” to P , whereas polygon decomposition asks for partitioning P into a set of basic polygonal elements (e.g., triangles) whose size is as small as possible. In this article, we present three different solutions for the cavity decomposition problem, which are obtained by suitably combining existing algorithms for polygon schematization and decomposition, by considering different input parameters, and by addressing both methodological and implementation issues. Since it is difficult to compare the three solutions on a theoretical basis, we present an extensive experimental study, employing both real-world and random data, conducted to assess their performance. We rank the proposed solutions according to the results of the experimental evaluation, and provide insights on natural candidates to be adopted, in practice, as modules of modern printed circuit board design software tools, depending on the observed performance and on the different constraints on the desired output.

A Pilot Study on the Degree of Tooth Staining Caused by Pollen Water and Chlorhexidine: In Vitro Study

Background: Chlorhexidine oral rinse has been used as an adjuvant in the treatment of periodontal disease. However, there are drawbacks of using chlorhexidine i.e. tooth staining and other side effects, including allergy reaction. In light of the proven therapeutic properties of pollen water as well as its relatively cheap cost in the market, pollen water has a potential to be an effective alternative to chlorhexidine oral rinse. The aim of this study is to compare the degree of tooth staining influenced by water-based pollen mouthwash to the standard Chlorhexidine mouthwash using spectrophotometer. Materials and Methods: 24 specimens from extracted intact human teeth were soaked into the three different solutions, Chlorhexidine, Pollen water (date palm pollen water suspension), and normal water. Color measurements were carried out by a spectrophotometer devise and recorded at 5 different time intervals. Color change (∆E), Chroma (C*) and Hue (H*) were analyzed and compared among the three solutions. Results: Overall mean ∆E was similar in all groups, significant difference between all time points was found only in pollen water. The change in C* was higher in pollen water as compared to other solutions. There was a subtle increase in H* in the Chlorhexidine samples after week 3. The H* values in pollen water were stable, but a sudden decrease was observed in week 6. The difference in H* among the three solutions was significant after 3 weeks. Conclusion: Within the limitation of our study, it can be concluded that Pollen water stained teeth to a lesser extent than did chlorhexidine. It might be beneficial to use Pollen water as mouthwash however, further investigation is needed regarding the efficacy of plaque control.

Raportul dintre libertate și interdicție în cazul magistraților

We are going to analyse three solutions which were adopted by a committee of the Superior Judicial Council (CSM) on the 23rd of November 2021, regarding the incompatibilities and restrictions applicable to magistrates (judges and prosecutors). All three solutions raise the common issues of the (lack of) competence of the Superior Judicial Council to interpret the law outside disciplinary procedures, as well as the manner in which the balance between freedom and restrictions was assessed. Even though the restrictions for magistrates are numerous, freedom is still the general rule and has to be preserved as such. Any incompatibilities and restrictions must be stated in an explicit and limitative manner by the law, and their interpretation must be a restrictive one.

Ordinary Versus Novel Particle With the Example of Their Spontaneous Transition

The bicubic equation of particle limiting velocity formalism yields three solutions c1, c2 and c3, (primary, secondary and tertiary) limiting velocities in terms of the congruent parameter  which is defined in terms of m, v, and E, respectively being particle mass, velocity and energy. The bicubic equation discriminant D is given in terms of the congruent parameter z(m). When one has z2(m) ≤ 1 with the discriminant satisfying D ≤ 0 then we are talking about limiting velocities of ordinary particles. Good examples are the relativistic particles such as electron, neutrino,etc., with luminal limiting velocity c3 = c and calculated superluminal c2, and imaginary superluminal c1, all corresponding to the real particle energy. On the specific level, the situations like these, we discuss in the muon neutrino velocities with the OPERA detector and the electron velocities from the 2010 Grab Nebula Flare. The z(m) = 1 value separates the ordinary particles from novel particles, associated with D ⪰ 0 and z2 ⪰ 1 with new novel particle limiting velocity solutions c1, c2 and c3 which depend, in addition to z(m), also on the congruent angle α(m), nonlinearly related to z(m). These solutions are discussed on the newly defined sterile neutrino which here is modeled as an ordinary particle with z2 ⪯ 1 spontaneously transiting via z(m) = 1 into the modeled novel sterile neutrino with z2 ⪰ 1. All ordinary and novel particles limiting velocities carry real particle energies; the ordinary particle limiting velocity solutions being in quadratic forms, while the novel particle limiting velocity solutions being respectively, in quadratic complex form, linear complex form, and just congruent angle α complex quadratic form.

The influence of information configuration on mobile game download

PurposeThe study aims to show how several factors interact to promote mobile game download: the number of games released by a publisher, the quality of the games released, the popularity of a game's genre, the quality of borrowed intellectual property, the frequency of recommendations, intragenre ranking, consumer rating and review quantity.Design/methodology/approachSignaling theory was used to classify the mobile game information displayed on the Apple App Store into four groups. A conceptual model was proposed to illustrate the complex relationship between the information and download. Based on information on 203 mobile games in the seven days following their release, the model was empirically tested to identify the influence of information configuration on game download by combining fuzzy qualitative comparative analysis (fsQCA) and a fuzzy cognitive map (FCM).FindingsThree solutions were identified for high game download and two for low/medium. The number of previous games released by a publisher, intragenre ranking, consumer rating and review quantity are core conditions that reinforce high game download. The effects of one information type on another and on downloads change as coexisting information types change.Originality/valueThis study enriches existing knowledge about how combinations of multiple types of game information lead to game download and extends previous variance-based research. Combining an FCM with fsQCA can facilitate one’s understanding of the complex causal relationships between game information and download.

Complex ekphrasis of the Hermitage moving in the latest russian poetry

Poetic ekphrasis may be not only simple, like a description of a work of art as a system of images that naturally come to life in an artistic description, but also complex, meaning the stay of exhibits in a museum or gallery. Complex ekphrasis is used also be different, in contrast to the type of contextualization of exhibits in the space intended for them, and a special ekphrasis of movement can be distinguished, where it is not the delay in front of the exhibits that is important, but the experience of the museum space itself as strange, existentially significant and associated with key existential moments in the life of a lyric character. In such a subspecies of ekphrasis, it is not the action of the imagination that is essential, but the skills of orientation in a value-marked space, with signs of up and down, openness and closeness, due to which the return of aesthetic experience in a complex existential situation is thought. The article offers a close reading of several examples of such an ekphrasis of gallery movement. In the poetry of Mikhail Eremin, the Saint Petersburg Hermitage turns out to be, first of all, a place of various forms of reflection, and the overlap between the metaphorical (reflection and attention to the phonetics of speech) and literal (mirror) understanding of reflection forms a mechanism for the quickest transition from spatial confusion to the aesthetic experience of the Hermitage collection. In the poetry of Sergei Stratanovsky, on the contrary, the Hermitage is shown through the eyes of a conventional character, immune to culture, where the mechanisms of such a transition are absent, and any attempt to simplify spatial self-awareness turns into a total immunity to art. In the poetry of Asya Veksler, the Hermitage turns out to be a hero with its own subjectivity, modeled on Petersburg in Anna Akhmatova's Poem Without a Hero, and this allows the episodes of a love drama to be developed as confirmed by various formal decisions and to erase the border between the aesthetics of space premises and the aesthetics of works. All three solutions imply the general properties of a complex ekphrasis of displacement: 1) a presence of an existential basis of a poetic utterance, detached from the usual modes of relations with time, partially blocking the usual modes of aesthetic perception of works of art, 2) a constant search for means of overcoming this blocking, which can be successful, if associated with the acceleration of sensory experiences, and unsuccessful if associated with frustration and/or routine admiration, 3) a situation in which architectural and design decisions are perceived as deeply symbolic and valuable, while works of art remain mysteries among other mysteries, and only the correctly found speed of mental work with the past and the present allows them to be perceived, 4) uses of the names of artists and plots of works not as symbols, but as part of the route, with the ambiguity of this route, the lack of sufficient motivation for it in the plot, but partial support from the book explications or educational habits, 5) an attention to the formal components of both the interior and individual works, as the only key to integrating these solutions into large value oppositions. A close reading of these poems allows for a better understanding of the importance of formal analysis for a comprehensive understanding of fine art and plastics and their reflection in literature as an art that deals with different modes of sensing time.

Comparative analysis of the hybrid power system topology for a high efficiency prototype vehicle

The paper presents a comparative analysis of three solutions of the power supply topology of a high-efficiency hybrid vehicle. The analysis was carried out for the Hydros prototype vehicle developed at the Lublin University of Technology for the Shell Eco Marathon competition. This vehicle is driven by an electric motor powered by two energy sources: hydrogen fuel cells and supercapacitors, allowing temporary energy buffering. Three variants of the mutual connection of the two energy sources to a single receiver were analysed, taking into account the voltage converter systems between the individual components of the system. The aim of these analyses was to determine the most energy-efficient solution.

Influence of supporting electrolyte on electrochemical formation of copper nanoparticles and their electrocatalytic properties

Comparative analysis of copper nanoparticles (CuNPs) obtained by electrodeposition on highly oriented pyrolytic graphite (HOPG) substrates from different supporting electrolytes containing sulphate anions, was performed. Voltammetric results indicated that Cu electrodeposition follows a diffusion-controlled nucleation and crystal growth model for three solutions studied (Na2SO4, H2SO4 and Na2SO4+H2SO4). Na2SO4 solution was found to be most effective because the copper reduction occurs at most positive potential value, reaching the highest current density. Analysis of potentiostatic current transients revealed that the process can be described predominantly by a model involving 3D-progressive nucleation mechanism, which was corroborated by scanning electron microscopy (SEM) analysis. SEM images showed high density of hemispherical shaped Cu particles of different sizes (mostly between 80-150 nm), randomly distributed on the HOPG surface for Na2SO4 electrolyte solution. In the presence of H2SO4, the size dispersion decreased, resulting in particles with greater diameters (up to 339 nm). The use of electrolyte solution with Na2SO4+H2SO4 revealed lower particle density with a considerable crystal size dispersion, where very small crystallites are prevailing. Cyclic voltammetry was used to evaluate qualitatively the catalytic activity of CuNPs deposited from three electrolyte solutions towards the nitrate reduction reaction. An enhanced catalytic effect was obtained when copper particles were prepared from either Na2SO4 or H2SO4 supporting electrolytes.