While periodically-driven phases offer a unique insight into non-equilibrium topology that is richer than its static counterpart, their experimental realization is often hindered by ubiquitous decoherence effects. Recently, we have proposed a decoherence-free approach of realizing these Floquet phases. The central insight is that the reflection matrix, being unitary for a bulk insulator, plays the role of a Floquet time-evolution operator. We have shown that reflection processes off the boundaries of systems supporting higher-order topological phases (HOTPs) simulate non-trivial Floquet phases. So far, this method was shown to work for one-dimensional Floquet topological phases protected by local symmetries. Here, we extend the range of applicability by studying reflection off three-dimensional HOTPs with corner and hinge modes. We show that the reflection processes can simulate both first-order and second-order Floquet phases, protected by a combination of local and spatial symmetries. For every phase, we discuss appropriate topological invariants calculated with the nested scattering matrix method.
In this paper we consider the problem of finding a Nash equilibrium (NE) via zeroth-order feedback information in games with merely monotone pseudogradient mapping. Based on hybrid system theory, we propose a novel extremum seeking algorithm which converges to the set of Nash equilibria in a semi-global practical sense. Finally, we present two simulation examples. The first shows that the standard extremum seeking algorithm fails, while ours succeeds in reaching NE. In the second, we simulate an allocation problem with fixed demand.
Optical time-domain reflectometer (OTDR) is used to characterize fiber optic links by identifying and localizing various refractive and reflective events such as breaks, splices, and connectors, and measuring insertion/return loss and fiber length. Essentially, OTDR inserts a pulsed signal into the fiber, from which a small portion that is commonly referred to as Rayleigh backscatter, is continuously reflected back with appropriate delays of the reflections expressed as the power loss versus distance, by conveniently scaling the time axis. Specifically, for long-distance events visibility and measurement accuracy, the crucial OTDR attribute is dynamic range, which determines how far downstream the fiber can the strongest transmitted optical pulse reach. As many older-generation but still operable OTDR units have insufficient dynamic range to test the far-end of longer fibers, we propose a simple and cost-effective solution to reactivate such an OTDR by inserting a low-noise high-gain optical preamplifier in front of it to lower the noise figure and thereby the noise floor. Accordingly, we developed an appropriate dynamic range and distance span extension model which provided the exemplar prediction values of 30 dB and 75 km, respectively, for the fiber under test at 1550 nm. These values were found to closely match the dynamic range and distance span extensions obtained for the same values of the relevant parameters of interest by the preliminary practical OTDR measurements conducted with the front-end EDFA optical amplifier, relative to the measurements with the OTDR alone. This preliminary verifies that the proposed concept enables a significantly longer distance span than the OTDR alone. We believe that the preliminary results reported here could serve as a hint and a framework for a more comprehensive test strategy in terms of both test diversification and repeating rate, which can be implemented in a network operator environment or professional lab.
Forests in Europe are, at present not endangered by soil erosion, however, this can change with climate change or intensified forest management practices. Using a newly established network of plots in beech forests across Europe, the aims of this study were 1) discrimination of soil properties and erodibility indices in relation to bedrock, 2) determination of geochemical properties and Corg influencing erodibility, and 3) assessment of the effect of soil depth on erodibility indices. Seventy-six soil samples from 20 beech forests were collected in 11 countries to quantify soil properties influencing erodibility indices clay ratio, modified clay ratio, sodium adsorption ratio, and oxides ratio. Results indicate that dominant soil properties, determined by bedrock, that correlate with forest soil erodibility indices are: Corg, pH, EC, Ca and Na ion concentrations, total-water soluble cations, and the % of sand. According to the tested indices, soil susceptibility to erosion follows the sequence: granite>andesite>sandstone>quartzite>limestone. Deeper soil horizons on granite are more susceptible to erosion than surface horizons, while this is not the case for soils on limestones. In conclusion, forest management should consider the predisposition of different soil types to erosion.
Paint production and for that colour mixing is an important process which has wide applications in several field. There are various kinds of colour mixing that can be done. It can either be additive colour mixing or subtractive colour mixing. Generally, there are various kinds of paint mixing machines available in the market. They vary in their size, shape, technology and methodologies. The aim of this paper is to present a calculation and analyse of hydraulic system for paint mixing machine. The paint mixing machine has the task of mixing the oil paint components in vessel until the finished mass is obtained. As oil paint is a typical representative of rheological materials where the viscosity depends on the shear rate, it is necessary to mix different paint structures during processing at different speeds - the number of revolutions of the propeller must be changes.
Based on kadi sicils and Franciscan chronicles, this paper seeks to present a picture of everyday lives of Christians and Muslims during a turbulent period, marked by political turmoil, unrest and general insecurity. Attacks, murders and various other acts of violence were part of everyday life. The ruling class of the time often abused their position and acted beyond their authority, putting additional pressure on the Christian population and further aggravating their social position and security within Eyalet of Bosnia. The efforts of the authorities to protect reaya were only temporarily effective in stopping the violence. The
Abstract. Alongside climate change, the introduction of non-native species (NNS) is widely recognized as one of the main threats to aquatic biodiversity and human wellbeing. Non-native species and biodiversity are generally low priority issues on the political agendas of many countries, particularly in European countries outside the European Union (EU). The objectives and tasks of this study were to address the policy regulation, education level, education practices, and socioeconomic perceptions of NNS in the Balkans. A questionnaire-based survey was conducted in Albania, Bosnia and Herzegovina, Montenegro, North Macedonia and Turkey (Balkan EU candidate and potential candidate members), in Croatia and Greece (Balkan EU Member States) and Italy (non-Balkan EU Member State). The EU Alien Regulation (1143/2014) concerning NNS is implemented in EU Member States and Montenegro, whereas Albania, Bosnia and Herzegovina and Turkey have not reported specific policy regulations for NNS. Permanent monitoring programmes specifically designed for NNS have not yet been established in the EU Member States. Most countries tackle the issue of NNS through educational activities as part of specific projects. Education level is indicative of the implementation of NNS policy regulation, and efforts are needed for the proper development of relative study programmes. Public awareness and educational preparedness concerning NNS in the Balkans were identified as poor. Strong programmes for management and education should be developed to increase public awareness to prevent further biodiversity losses in the Balkan region.
The OPENQKD project is demonstrating deployed QKD networks in several European cities. We present a virtual QKD testbed that allows the user to monitor live data but also to re-enact the past QKD exchange over the various links, together with a QKD network simulation tool.
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