RFI Considerations for Utility of the Galileo E6 Signal

Peer reviewe

Radio-Frequency Interference Considerations for Utility of the Galileo E6 Signal Based on Long-Term Monitoring by ARFIDAAS

The extent to which navigation signals in the E6 band may be impacted by shared spectrum allocations might be underappreciated. This paper presents top-level observations from a multi-year international radio frequency interference (RFI) monitoring project covering all L-band global navigation satellite system (GNSS) signals with specific focus on the challenges facing the E6 band. The context of this paper is the assumption that most users will be non-authorized and have access to only the open data-bearing signal component and not the encrypted pilot of the E6 Galileo signal. In virtually all locations where the Advanced RFI Detection, Analysis, and Alerting System (ARFIDAAS) monitoring stations were deployed, frequent disruption of the E6 band from systems such as radar installations or other authorized users of the spectrum was observed. In the presented paper, an effort is made to put the observations in the context of the expected use cases of the E6 signal.publishedVersio

Religious transformations in the Middle Ages: towards a new archaeological agenda

The study of religious change in Europe between the collapse of the Roman Empire and the Reformation forms one of the cornerstones of medieval archaeology but has been riven by period, denominational and geographical divisions. This paper lays the groundwork for a fundamental rethink of archaeological approaches to medieval religions, by adopting a holistic framework that places Christian, pagan, Islamic and Jewish case studies of religious transformation in a long-term, comparative perspective. Focused around the analytical themes of ‘hybridity and resilience’ and ‘tempo and trajectories’, our approach shifts attention away from the singularities of national narratives of religious conversion towards a deeper understanding of how religious beliefs, practices and identity were renegotiated by medieval people in their daily lives

Semiclassical theory of a disordered two-dimensional SNS-junction

Two-dimensional hybrid superconductor-semiconductor structures provide a promising platform for realising networks of Majorana fermions for fault-tolerant quantum computing, and, as such, are attracting a lot of attention. Recently, two-dimensional superconductor-normal material-superconductor (SNS) junctions created in such hybrid systems, exhibited dramatic asymmetries in their Fraunhofer-like patterns of the critical current as a function of applied magnetic field. It was proposed that, apart from spin-orbit interaction and Zeeman effects, disorder inside the junction can play an important role in the appearance of these asymmetries. This thesis investigates the role of disorder in two-dimensional SNS-junctions by developing a toy model in a semiclassical picture. This model assumes two distinct paths across the junction, connected by beamsplitters at the normal material-superconductor (NS) interfaces, enclosing a magnetic flux. By describing these paths as ballistic, one-dimensional nanowires, and using a scattering matrix approach to describe the beamsplitters, we develop a method for calculating the transmission and reflection coefficients of the junction as a whole. This allows us to control the coupling between the nanowires and the NS-interfaces, as well as to introduce an asymmetric probability injection into the two arms and to incorporate a difference in the two path lengths. The supercurrent through the junction is found from the energy of the Andreev bound states, which allows us to investigate the critical current as a function of the magnetic flux penetrating the surface enclosed by the two paths. We find that, in the absence of spin-dependent effects such as spin-orbit interaction and the Zeeman effect, none of the combinations of asymmetric probability injection, different path lengths, modifications of the chemical potential or NS coupling strength produces asymmetries in the critical current, such as observed in the experiment. We thus conclude that either our toy model is not sufficiently complex, e.g., one would need more than two interfering trajectories, or that disorder alone is not sufficient to produce asymmetric patterns of critical currents. Further research is required to in order to to determine which conclusion is correct

Effects of Toasting Time on Digestive Hydrolysis of Soluble and Insoluble 00-Rapeseed Meal Proteins

Thermal damage to proteins can reduce their nutritional value. The effects of toasting time on the kinetics of hydrolysis, the resulting molecular weight distribution of 00-rapeseed meal (RSM) and the soluble and insoluble protein fractions separated from the RSM were studied. Hydrolysis was performed with pancreatic proteases to represent in vitro protein digestibility. Increasing the toasting time of RSM linearly decreased the rate of protein hydrolysis of RSM and the insoluble protein fractions. The extent of hydrolysis was, on average, 44% higher for the insoluble compared with the soluble protein fraction. In contrast, the rate of protein hydrolysis of the soluble protein fraction was 3–9-fold higher than that of the insoluble protein fraction. The rate of hydrolysis of the insoluble protein fraction linearly decreased by more than 60% when comparing the untoasted to the 120 min toasted RSM. Increasing the toasting time elicited the formation of Maillard reaction products (furosine, N (ε)-carboxymethyl-lysine and N (ε)-carboxyethyl-lysine) and disulfide bonds in the insoluble protein fraction, which is proposed to explain the reduction in the hydrolysis rate of this fraction. Overall, longer toasting times increased the size of the peptides resulting after hydrolysis of the RSM and the insoluble protein fraction. The hydrolysis kinetics of the soluble and insoluble protein fractions and the proportion of soluble:insoluble proteins in the RSM explain the reduction in the rate of protein hydrolysis observed in the RSM with increasing toasting time