scholarly journals Distortion of meteor count rates due to cosmic radio noise and atmospheric particularities

2010 ◽  
Vol 8 ◽  
pp. 237-241 ◽  
Author(s):  
G. Stober ◽  
C. Jacobi ◽  
D. Keuer
Keyword(s):  
Relative Difference ◽  
Cosmic Radio ◽  
Radio Noise ◽  
Noise Sources ◽  
Meteor Flux ◽  
Electron Line ◽  
Meteor Detection ◽  
Sporadic E ◽  
Atmospheric Phenomena ◽  
The Impact

Abstract. The determination of the meteoroid flux is still a scientifically challenging task. This paper focusses on the impact of extraterrestrial noise sources as well as atmospheric phenomena on the observation of specular meteor echoes. The effect of cosmic radio noise on the meteor detection process is estimated by computing the relative difference between radio loud and radio quiet areas and comparing the monthly averaged meteor flux for fixed signal-to-noise ratios or fixed electron line density measurements. Related to the cosmic radio noise is the influence of D-layer absorption or interference with sporadic E-layers, which can lead to apparent day-to-day variation of the meteor flux of 15–20%.

scholarly journals Improved adherence with Medicines Use Review service in Slovenia: a randomized controlled trial

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Urška Nabergoj Makovec ◽  
Igor Locatelli ◽  
Mitja Kos
Keyword(s):  
Medication Adherence ◽  
Controlled Trial ◽  
Test Group ◽  
Multiple Linear Regression Model ◽  
Relative Difference ◽  
Control Group ◽  
Adherence Support ◽  
Medicines Use ◽  
The Impact ◽  
Medicines Use Review

Abstract Background Based on several existing patient-oriented activities, Medicines Use Review (MUR) service was standardized and officially adopted in Slovenia in 2015. Service aims to provide adherence support and ensure safe and effective medicines use. Therefore, the aim of the study was to evaluate the benefits of MUR in Slovenia, primarily the impact on medication adherence. Methods A randomised controlled trial was performed in community pharmacies to compare MUR with standard care. Patients were randomised into either the test (patients received MUR by a certified MUR provider at visit 1), or control group. The study primary outcome was self-reported adherence to multiple medications, assessed by electronic ©Morisky Widget MMAS-8 Software at the first visit (V1) and after 12 weeks (V2). A sub-analysis of intentional and unintentional non-adherence was performed. MUR impact was defined as the relative difference in ©MMAS-8 score after 12 weeks between the test and control group. A multiple linear regression model was used to predict MUR impact based on baseline adherence (low versus medium and high). Several secondary outcomes (e.g. evaluation of drug-related problems (DRPs)) were also assessed. Results Data from 153 (V1) and 140 (V2) patients were analysed. Baseline adherence was low, moderate and high in 17.6, 48.4 and 34.0% patients, respectively. In the low adherence subpopulation, test group patients showed a 1.20 point (95% CI = 0.16–2.25) increase in total ©MMAS-8 score (p = 0.025) compared to control group patients. A 0.84 point (95% CI = 0.05–1.63) increase was due to intentional non-adherence (p = 0.038), and a 0.36 point (95% CI = − 0.23-0.95) was due to unintentional non-adherence (p = 0.226). Additionally, statistically significant decrease in the proportion of patients with manifested DRPs (p < 0.001) and concerns regarding chronic medicines use (p = 0.029) were revealed. Conclusion MUR service in Slovenia improves low medication adherence and is effective in addressing DRPs and concerns regarding chronic medicines use. Trial registration ClinicalTrials.gov - NCT04417400; 4th June 2020; retrospectively registered.

scholarly journals Exoplanet mass estimation for a sample of targets for the Ariel mission

2021 ◽  
Author(s):  
J. R. Barnes ◽  
C. A. Haswell
Keyword(s):  
Radial Velocity ◽  
Input Parameter ◽  
Noise Sources ◽  
Time Commitment ◽  
Low Mass ◽  
Time Required ◽  
Fixed Input ◽  
The Impact ◽  
Quadrature Sampling

AbstractAriel’s ambitious goal to survey a quarter of known exoplanets will transform our knowledge of planetary atmospheres. Masses measured directly with the radial velocity technique are essential for well determined planetary bulk properties. Radial velocity masses will provide important checks of masses derived from atmospheric fits or alternatively can be treated as a fixed input parameter to reduce possible degeneracies in atmospheric retrievals. We quantify the impact of stellar activity on planet mass recovery for the Ariel mission sample using Sun-like spot models scaled for active stars combined with other noise sources. Planets with necessarily well-determined ephemerides will be selected for characterisation with Ariel. With this prior requirement, we simulate the derived planet mass precision as a function of the number of observations for a prospective sample of Ariel targets. We find that quadrature sampling can significantly reduce the time commitment required for follow-up RVs, and is most effective when the planetary RV signature is larger than the RV noise. For a typical radial velocity instrument operating on a 4 m class telescope and achieving 1 m s−1 precision, between ~17% and ~ 37% of the time commitment is spent on the 7% of planets with mass Mp < 10 M⊕. In many low activity cases, the time required is limited by asteroseismic and photon noise. For low mass or faint systems, we can recover masses with the same precision up to ~3 times more quickly with an instrumental precision of ~10 cm s−1.

scholarly journals Prevalence of internalizing disorders, symptoms, and traits across age using advanced nonlinear models

2021 ◽  
pp. 1-10
Author(s):  
Hanna M. van Loo ◽  
Lian Beijers ◽  
Martijn Wieling ◽  
Trynke R. de Jong ◽  
Robert A. Schoevers ◽  
...  
Keyword(s):  
Internalizing Symptoms ◽  
Nonlinear Models ◽  
Generalized Additive Models ◽  
Population Sample ◽  
Internalizing Disorders ◽  
Relative Difference ◽  
Additive Models ◽  
Point Prevalence ◽  
Cross Sectional ◽  
The Impact

Abstract Background Most epidemiological studies show a decrease of internalizing disorders at older ages, but it is unclear how the prevalence exactly changes with age, and whether there are different patterns for internalizing symptoms and traits, and for men and women. This study investigates the impact of age and sex on the point prevalence across different mood and anxiety disorders, internalizing symptoms, and neuroticism. Methods We used cross-sectional data on 146 315 subjects, aged 18–80 years, from the Lifelines Cohort Study, a Dutch general population sample. Between 2012 and 2016, five current internalizing disorders – major depression, dysthymia, generalized anxiety disorder, social phobia, and panic disorder – were assessed according to DSM-IV criteria. Depressive symptoms, anxiety symptoms, neuroticism, and negative affect (NA) were also measured. Generalized additive models were used to identify nonlinear patterns across age, and to investigate sex differences. Results The point prevalence of internalizing disorders generally increased between the ages of 18 and 30 years, stabilized between 30 and 50, and decreased after age 50. The patterns of internalizing symptoms and traits were different. NA and neuroticism gradually decreased after age 18. Women reported more internalizing disorders than men, but the relative difference remained stable across age (relative risk ~1.7). Conclusions The point prevalence of internalizing disorders was typically highest between age 30 and 50, but there were differences between the disorders, which could indicate differences in etiology. The relative gap between the sexes remained similar across age, suggesting that changes in sex hormones around the menopause do not significantly influence women's risk of internalizing disorders.

scholarly journals Quantum Divide and Compute: Exploring the Effect of Different Noise Sources

2021 ◽  
Vol 2 (3) ◽  
Author(s):  
Thomas Ayral ◽  
François-Marie Le Régent ◽  
Zain Saleem ◽  
Yuri Alexeev ◽  
Martin Suchara
Keyword(s):  
Success Probability ◽  
Quantum Circuit ◽  
Noise Sources ◽  
Output Distribution ◽  
Tensor Network ◽  
Learning Machine ◽  
Society Annual ◽  
The Impact ◽  
Noise Models ◽  
Detailed Derivation

AbstractOur recent work (Ayral et al. in Proceedings of IEEE computer society annual symposium on VLSI, ISVLSI, pp 138–140, 2020. 10.1109/ISVLSI49217.2020.00034) showed the first implementation of the Quantum Divide and Compute (QDC) method, which allows to break quantum circuits into smaller fragments with fewer qubits and shallower depth. This accommodates the limited number of qubits and short coherence times of quantum processors. This article investigates the impact of different noise sources—readout error, gate error and decoherence—on the success probability of the QDC procedure. We perform detailed noise modeling on the Atos Quantum Learning Machine, allowing us to understand tradeoffs and formulate recommendations about which hardware noise sources should be preferentially optimized. We also describe in detail the noise models we used to reproduce experimental runs on IBM’s Johannesburg processor. This article also includes a detailed derivation of the equations used in the QDC procedure to compute the output distribution of the original quantum circuit from the output distribution of its fragments. Finally, we analyze the computational complexity of the QDC method for the circuit under study via tensor-network considerations, and elaborate on the relation the QDC method with tensor-network simulation methods.

scholarly journals Covid-19: Early evening curfews are not effective and may backfire

2021 ◽  
Author(s):  
Sotiris Vandoros ◽  
Alina Velias ◽  
Sotiris Georganas
Keyword(s):  
Natural Experiment ◽  
Relative Difference ◽  
Relative Increase ◽  
Percentage Points ◽  
Early Evening ◽  
Before And After ◽  
Clear Identification ◽  
Econometric Approach ◽  
The Impact ◽  
Indoor Spaces

Background: During the COVID-19 pandemic, some countries have introduced early evening curfews. Several studies try measure the effectiveness of such measures across different countries, but clear identification of effects is elusive. Objective: We examined the impact of an early evening curfew on mobility by studying a shift in curfews from 9pm to 6pm in Greece. Data and Methods: We took advantage of a natural experiment in Greece, where curfews shifted from 9pm to 6pm in one Region, but not in another. We followed a difference-in-difference econometric approach, where we compared trends in mobility in groceries and pharmacies as well as residential spaces before and after the introduction of the 6pm curfew, in the two regions. Results: The relative difference in the time spent in groceries and pharmacies between the two regions before and after the intervention, is statistically insignificant [coeff: -9.95; 95%CI -44.358 to 24.458]. The relative increase in time spent in groceries and pharmacies after the 6pm curfew was only 4.625 percentage points [coeff: 4.625; 95%CI 1.412 to 7.838]. Conclusions: We found that the 6pm instead of 9pm curfew in Athens led to a 4.63 percentage point relative increase in time spent at home and had no effect on time spent in groceries and pharmacies. Considering that this was a result of a 18.75% reduction in hours where people were allowed to leave home, it seems that the early evening curfew led to more crowding in indoor spaces; which may facilitate the spread of disease. Lockdowns and other measures are necessary to tackle Covid-19, but it is important to avoid substitution by activities that contribute further to spreading the virus. Interventions should therefore be based on a thorough analysis of human behaviour.

Effect of Rotor-Stator Configuration in the Generation of Vortical Scales and Wake Mixing in Single Stage Axial Fans: Part II — Assessment of Vortex Sound Sources

2013 ◽  
Author(s):  
Mónica Galdo Vega ◽  
Jesus Manuel Fernandez Oro ◽  
Katia María Argüelles Díaz ◽  
Carlos Santolaria Morros
Keyword(s):  
Deep Understanding ◽  
Operating Conditions ◽  
Axial Fan ◽  
Noise Sources ◽  
Sound Sources ◽  
Time Resolved ◽  
Vortex Sound ◽  
Starting Point ◽  
Axial Fans ◽  
The Impact

This second part is devoted to the identification of vortex sound sources in low-speed turbomachinery. As a starting point, the time-resolved evolution of the vortical motions associated to the wake shear layers (reported in the first part of the present study) is employed to obtain vorticity distributions in both blade-to-blade and traverse locations throughout the axial fan stage. Following, the Powell analogy for generation of vortex sound is revisited to obtain the noise sources in the nearfield region of the fan. Both numerical and experimental databases presented previously are now post-processed to achieve a deep understanding of the aeroacoustic behavior of the vortical scales present in the flow. A LES simulation at midspan, using a 2.5D scheme, allows an accurate description of the turn-out time of the shedding vortices, within high-density meshes in the blades and vanes passages, and a correct modeling of the dynamics of turbulence. Besides, thermal anemometry has been employed with a two-wire probe to measure the planar flow in the midspan sections of the fan. Statistical procedures and signal conditioning of velocity traces have confirmed experimentally the unsteady flow patterns devised in the numerical model. The comparison of the rotor-stator and the stator-rotor configurations provides the influence of the wake mixing and the nucleation of turbulent spots in the distribution of the Powell source terms. Moreover, the relation between the turbomachine configuration and the generation of vortex sound can be established, including the impact of the operating conditions and the contributions of the interaction mechanisms.

Long-term structural monitoring of multi-story RC structures, based on data extracted from ambient noise and earthquake vibrations

2021 ◽  
Author(s):  
Alexandru Tiganescu ◽  
Bogdan Grecu ◽  
Iolanda-Gabriela Craifaleanu ◽  
Dragos Toma-Danila ◽  
Stefan-Florin Balan
Keyword(s):  
Monitoring System ◽  
Ambient Noise ◽  
Critical Issue ◽  
Seismic Events ◽  
Noise Sources ◽  
Rc Structures ◽  
Infrastructure Monitoring ◽  
Human Operators ◽  
The Impact

&lt;p&gt;The impact of natural hazards on structures and infrastructures is a critical issue that needs to be properly addressed by both public and private entities. To better cope with seismic hazard and to mitigate the risk, long-term multi-sensor infrastructure monitoring represents a useful tool for acquiring information on their condition and vulnerability. However, the current increasing data volume collected using sensors is not suitable to be processed with classical standalone methods. Thus, automatic algorithms and decision-making frameworks should be developed to use this data, with minimum intervention from human operators. A case-study for the application of advanced methods is focused on the headquarters of the Institute for Atomic Physics, a 11-story reinforced concrete building, located near Bucharest, Romania. The instrumentation scheme consists of accelerometers installed at the basement, at an intermediate floor and at the top of the structure. The data were continuously recorded, starting with December 2013. More than 80 seismic events with moment magnitude, M&lt;sub&gt;W&lt;/sub&gt;, larger than 3.8 were recorded during the monitoring period. The current study covers the long-term evolution and variation of dynamic parameters (one value per hour), based on both ambient noise sources and small and medium magnitude seismic events. The seasonal variation of these parameters will be determined, as well as their daily variation and the differences between values obtained from ambient noise and from earthquake-induced vibrations. Other atmospheric parameters (e.g. temperature, precipitation, wind speed) will be considered in future studies. The goal of the PREVENT project, in the framework of which the research is performed, is to collect multi-disciplinary data and to integrate them into a complex monitoring system. The current study achieved the first step, focusing on data from the seismic sensors and setting up the premises for a multi-sensor, multi-parameter, more reliable infrastructure monitoring system.&amp;#160;&amp;#160;&lt;/p&gt;

scholarly journals Comparison of eddy covariance CO<sub>2</sub> and CH<sub>4</sub> fluxes from mined and recently rewetted sections in a northwestern German cutover bog

2020 ◽  
Vol 17 (10) ◽  
pp. 2853-2874 ◽  
Author(s):  
David Holl ◽  
Eva-Maria Pfeiffer ◽  
Lars Kutzbach
Keyword(s):  
Carbon Dioxide ◽  
Land Use ◽  
Time Series ◽  
Eddy Covariance ◽  
Relative Difference ◽  
Plant Litter ◽  
Absolute Difference ◽  
Data Set ◽  
Ch4 Flux ◽  
The Impact

Abstract. With respect to their role in the global carbon cycle, natural peatlands are characterized by their ability to sequester atmospheric carbon. This trait is strongly connected to the water regime of these ecosystems. Large parts of the soil profile in natural peatlands are water saturated, leading to anoxic conditions and to a diminished decomposition of plant litter. In functioning peatlands, the rate of carbon fixation by plant photosynthesis is larger than the decomposition rate of dead organic material. Over time, the amount of carbon that remains in the soil and is not converted back to carbon dioxide grows. Land use of peatlands often goes along with water level manipulations and thereby with alterations of carbon flux dynamics. In this study, carbon dioxide (CO2) and methane (CH4) flux measurements from a bog site in northwestern Germany that has been heavily degraded by peat mining are presented. Two contrasting types of management have been implemented at the site: (1) drainage during ongoing peat harvesting on one half of the central bog area and (2) rewetting on the other half that had been taken out of use shortly before measurements commenced. The presented 2-year data set was collected with an eddy covariance (EC) system set up on a central railroad dam that divides the two halves of the (former) peat harvesting area. We used footprint analysis to split the obtained CO2 and CH4 flux time series into data characterizing the gas exchange dynamics of both contrasting land use types individually. The time series gaps resulting from data division were filled using the response of artificial neural networks (ANNs) to environmental variables, footprint variability, and fuzzy transformations of seasonal and diurnal cyclicity. We used the gap-filled gas flux time series from 2 consecutive years to evaluate the impact of rewetting on the annual vertical carbon balances of the cutover bog. Rewetting had a considerable effect on the annual carbon fluxes and led to increased CH4 and decreased CO2 release. The larger relative difference between cumulative CO2 fluxes from the rewetted (13±6 mol m−2 a−1) and drained (22±7 mol m−2 a−1) section occurred in the second observed year when rewetting apparently reduced CO2 emissions by 40 %. The absolute difference in annual CH4 flux sums was more similar between both years, while the relative difference of CH4 release between the rewetted (0.83±0.15 mol m−2 a−1) and drained (0.45±0.11 mol m−2 a−1) section was larger in the first observed year, indicating a maximum increase in annual CH4 release of 84 % caused by rewetting at this particular site during the study period.

scholarly journals Structure of All-Digital Frequency Synthesiser for IoT and IoV Applications

Electronics ◽  
2018 ◽  
Vol 8 (1) ◽  
pp. 29 ◽  
Author(s):  
Marijan Jurgo ◽  
Romualdas Navickas
Keyword(s):  
Phase Noise ◽  
Digital Filter ◽  
High Performance ◽  
Domain Model ◽  
Infinite Impulse Response ◽  
Type I ◽  
Noise Sources ◽  
Digital Frequency ◽  
Digitally Controlled Oscillator ◽  
The Impact

In recent years number of Internet of Things (IoT) services and devices is growing and Internet of Vehicles (IoV) technologies are emerging. Multiband transceiver with high performance frequency synthesisers should be used to support a multitude of existing and developing wireless standards. In this paper noise sources of an all-digital frequency synthesiser are discussed through s-domain model of frequency synthesisers, and the impact of noise induced by main blocks of synthesisers to the overall phase noise of frequency synthesisers is analysed. Requirements for time to digital converter (TDC), digitally controlled oscillator (DCO) and digital filter suitable for all-digital frequency synthesiser for IoT and IoV applications are defined. The structure of frequency synthesisers, which allows us to meet defined requirements, is presented. Its main parts are 2D Vernier TDC based on gated ring oscillators, which can achieve resolution close to 1 ps; multi core LC-tank DCO, whose tuning range is 4.3–5.4 GHz when two cores are used and phase noise is −116.4 dBc/Hz at 1 MHz offset from 5.44 GHz carrier; digital filter made of proportional and integral gain stages and additional infinite impulse response filter stages. Such a structure allows us to achieve a synthesiser’s in-band phase noise lower than −100 dBc/Hz, out-of-band phase noise equal to −134.0 dBc/Hz and allows us to set a synthesiser to type-I or type-II and change its order from first to sixth.

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