false signal
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Abstract Modeling of broadband and narrowband signal mark detection is widely used for sonar and radar systems. In this work, the problem is considered in relation to hydroacoustics. The paper describes the formation of a stream of correctly detected and false signal marks and calculation of estimates of their parameters, taking into account the antenna characteristics as well as the processing parameters of the system being simulated. Also considered are the realistic distribution of false signal marks by heading angles and the influence of the Doppler effect on the estimation of the mark parameters. The resulting model can be used in simulation systems, in the formation of a stream of detected signal marks, and the development of tracking algorithms. The model can be also used for predictive calculations that determine the probability of detecting signal sources and their characteristics

In this paper, we propose a method for the rejection of the background from the superposition of signals from different, almost simultaneously occurring events in the calorimeter for the COMET experiment. The basic idea is to use the chi-squared distribution obtained from fitting the recorded shape of the signal with an average waveform. The elaborated method is applied for the reconstruction of events with overlapping signals from the electron and radiative capture of neutrons by the 175Lu nucleus, as well as overlapping signals from two electrons born as a result of the decay of muons in the bound state with an aluminum nucleus with impulses causing a “false” signal of the μ – e conversion. The method showed a good ability to separate events, meanwhile, the separation time is significantly less than the FWHM of the pulse shape.

Рассмотрена задача обнаружения радиолокационных дискретных составных частотных сигналов широкополосными приемниками с программными обнаружителями. Данный тип сигналов нашел большое применение в радиолокации благодаря высокой помехоустойчивости и энергетической скрытности. Для их обнаружения часто используют широкополосный энергетический обнаружитель, который измеряет энергию принятого сигнала, сравнивая ее с пороговым уровнем, и на основе этого выносит решение о наличии либо отсутствии сигнала. Недостатком таких устройств является факт срабатывания их на одиночные отчеты, которые могут и не являться полезным сигналом. За счет того, что обнаружение ведется в широкой полосе частот, ухудшаются возможности приема таких сигналов. Для повышения возможностей приема составных частотных сигналов применяются программные обнаружители. За счет определенных правил принятия решения возрастает качество обнаружения, а одиночные отчеты более не воспринимаются. В результате была разработана методика, позволяющая провести оценку вероятности правильного и ложного обнаружения сигналов широкополосным приемником с программным обнаружителем в системах связи с применением широкополосных сигналов на примере радиолокационных дискретных составных частотных сигналов. Показано преимущество применения программной обработки We considered the problem of detecting radar discrete composite frequency signals by broadband receivers with software detectors. This type of signal is widely used in radar due to its high noise immunity and energy secrecy. To detect them, a broadband energy detector is often used, which measures the energy of the received signal, comparing it with a threshold level, and, based on this, makes a decision on the presence or absence of a signal. The disadvantage of such devices is the fact that they are triggered for single reports, which may not be a useful signal. Due to the fact that the detection is carried out in a wide frequency band, the ability to receive such signals is impaired. To improve the reception capabilities of composite frequency signals, software detectors are used. Due to certain decision rules, the quality of detection increases, and single reports are no longer accepted. As a result, we developed a technique that makes it possible to assess the probability of correct and false signal detection by a broadband receiver with a software detector in communication systems using wideband signals using the example of discrete composite frequency radar signals. Here we show the advantage of using software processing

Abstract A key challenge in searches for resonant new physics is that classifiers trained to enhance potential signals must not induce localized structures. Such structures could result in a false signal when the background is estimated from data using sideband methods. A variety of techniques have been developed to construct classifiers which are independent from the resonant feature (often a mass). Such strategies are sufficient to avoid localized structures, but are not necessary. We develop a new set of tools using a novel moment loss function (Moment Decomposition or MoDe) which relax the assumption of independence without creating structures in the background. By allowing classifiers to be more flexible, we enhance the sensitivity to new physics without compromising the fidelity of the background estimation.

AbstractPsychological bias towards, or away from, prior measurements or theory predictions is an intrinsic threat to any data analysis. While various methods can be used to try to avoid such a bias, e.g. actively avoiding looking at the result, only data blinding is a traceable and trustworthy method that can circumvent the bias and convince a public audience that there is not even an accidental psychological bias. Data blinding is nowadays a standard practice in particle physics, but it is particularly difficult for experiments searching for the neutron electric dipole moment (nEDM), as several cross measurements, in particular of the magnetic field, create a self-consistent network into which it is hard to inject a false signal. We present an algorithm that modifies the data without influencing the experiment. Results of an automated analysis of the data are used to change the recorded spin state of a few neutrons within each measurement cycle. The flexible algorithm may be applied twice (or more) to the data, thus providing the option of sequentially applying various blinding offsets for separate analysis steps with independent teams. The subtle manner in which the data are modified allows one subsequently to adjust the algorithm and to produce a re-blinded data set without revealing the initial blinding offset. The method was designed for the 2015/2016 measurement campaign of the nEDM experiment at the Paul Scherrer Institute. However, it can be re-used with minor modification for the follow-up experiment n2EDM, and may be suitable for comparable projects elsewhere.

Published analysis of genetic material from field-collected tsetse (Glossina spp, primarily from the Palpalis group) has been used to predict that the distance (δ) dispersed per generation increases as effective population densities (De) decrease, displaying negative density-dependent dispersal (NDDD). Using the published data we show this result is an artefact arising primarily from errors in estimates of S, the area occupied by a subpopulation, and thereby in De. The errors arise from the assumption that S can be estimated as the area (S^) regarded as being covered by traps. We use modelling to show that such errors result in anomalously high correlations between δ^ and S^ and the appearance of NDDD, with a slope of -0.5 for the regressions of log(δ^) on log(D^e), even in simulations where we specifically assume density-independent dispersal (DID). A complementary mathematical analysis confirms our findings. Modelling of field results shows, similarly, that the false signal of NDDD can be produced by varying trap deployment patterns. Errors in the estimates of δ in the published analysis were magnified because variation in estimates of S were greater than for all other variables measured, and accounted for the greatest proportion of variation in δ^. Errors in census population estimates result from an erroneous understanding of the relationship between trap placement and expected tsetse catch, exacerbated through failure to adjust for variations in trapping intensity, trap performance, and in capture probabilities between geographical situations and between tsetse species. Claims of support in the literature for NDDD are spurious. There is no suggested explanation for how NDDD might have evolved. We reject the NDDD hypothesis and caution that the idea should not be allowed to influence policy on tsetse and trypanosomiasis control.

Abstract In this research, a novel antenna array named Linearly arranged Concentric Circular Antenna Array (LCCAA) is proposed concerning lower beamwidth, lower sidelobe level, sharp ability to detect the false signal, and impressive SINR performance. The performance of the proposed LCCAA beamformer is compared with geometrically identical existing beamformers using the conventional technique where the LCCAA beamformer shows the lowest beamwidth and sidelobe level(SLL) of 12.50°and -15.17 dB in equal element accordingly. However, the performance gets degraded due to looking direction error, and robust techniques- fixed diagonal loading (FDL), optimal diagonal loading (ODL), and variable diagonal loading (VDL) are applied to all the potential arrays to minimize this problem. Furthermore, the LCCAA beamformer is further simulated to reduce the sidelobe applying tapering techniques where the hamming window shows the best performance having 17.097 dB less sidelobe level compared to the uniform window. The proposed structure is also analyzed under a robust tapered (VDL-hamming) method which reduces around 69.92 dB and 48.39 dB more sidelobe level compared to conventional and robust techniques. Analyzing all the performances, it is clear that the proposed LCCAA beamformer is superior and provides the best performance with the proposed robust tapered (VDL-hamming) technique.

Fluoride has been employed in laboratory investigations since the early 20th century. These studies opened the understanding of fluoride interventions to fundamental biological processes. Millions of people living in endemic fluorosis areas suffer from various pathological disturbances. The practice of community water fluoridation used prophylactically against dental caries increased concern of adverse fluoride effects. We assessed the publications on fluoride toxicity until June 2020. We present evidence that fluoride is an enzymatic poison, inducing oxidative stress, hormonal disruptions, and neurotoxicity. Fluoride in synergy with aluminum acts as a false signal in G protein cascades of hormonal and neuronal regulations in much lower concentrations than fluoride acting alone. Our review shows the impact of fluoride on human health. We suggest focusing the research on fluoride toxicity to the underlying integrative networks. Ignorance of the pluripotent toxic effects of fluoride might contribute to unexpected epidemics in the future.