Effects of temperature variations in high-sensitivity Sagnac gyroscope

AbstractGINGERINO is one of the most sensitive Sagnac laser-gyroscopes based on an heterolithic mechanical structure. It is a prototype for GINGER, the laser gyroscopes array proposed to reconstruct the Earth rotation vector and in this way to measure General Relativity effects. Many factors affect the final sensitivity of laser gyroscopes, in particular, when they are used in long-term measurements, slow varying environmental parameters come into play. To understand the role of different terms allows to design more effective mechanical as well as optical layouts, while a proper model of the dynamics affecting long-term (low frequency) signals would increase the effectiveness of the data analysis for improving the overall sensitivity. In this contribution, we focus our concerns on the effects of room temperature and pressure aiming at further improving mechanical design and long-term stability of the apparatus. Our data are compatible with a local orientation changes of the Gran Sasso site below $$\mu $$ μ rad as predicted by geodetic models. This value is consistent with the requirements for GINGER and the installation of an high-sensitivity Sagnac gyroscope oriented at the maximum signal, i.e. along the Earth rotation axes.

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Relationships between soil physicochemical properties and nitrogen fixing, nitrifying and denitrifying under varying land-use practices in the northwest region of Argentina

Soil and Water Research ◽

10.17221/192/2017-swr ◽

2019 ◽

Vol 14 (No. 1) ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Carolina Pérez Brandan ◽

Annabel Meyer ◽

José Manuel Meriles ◽

Jorgelina Huidobro ◽

Michael Schloter ◽

...

Keyword(s):

Land Use ◽

Crop Rotation ◽

Environmental Parameters ◽

High Sensitivity ◽

Soil Samples ◽

The Other ◽

Marker Genes ◽

Negative Effect ◽

Microbial Groups

The aim of this study was to evaluate the response pattern of diazotrophic microbes, denitrifiers and nitrifiers to different types of land use management, such as soybean monoculture (M) during 5 and 24 years (M5 and M24) and soybean-maize rotation (R) during 4 and 15 years (R4 and R15) in two subsequent years at the time point of flowering. Soil samples from a site recently introduced into agriculture (RUA) and a pristine soil under native vegetation (NV) were used as controls. Abundances of different functional groups of microbes were assessed using the direct quantification of marker genes by quantitative real-time PCR using extracted DNA from rhizosphere samples. In addition, soil chemical and physical properties were analysed and correlated with the abundance data from the functional microbial groups under investigation. Overall, the results indicate that the abundance of nifH genes was higher under R treatments compared to M treatments. The abundance of ammonium monooxygenase genes amoA (AOA) was generally higher under rotation systems and decreased under M24. RUA evidenced a negative effect on the establishment and development of AOA communities. The influence of land use on nirS abundance was inconsistent. However, R treatments showed a high abundance of nirK genes compared to M treatments. In both growing seasons, the abundance of nosZ genes was higher under NV compared with the other treatments. Furthermore, M24 treatment was related to strongly changed chemical and physical soil properties compared with the other sites. As expected, soil samples from RUA showed the strong dynamics of measured parameters indicating the high sensitivity of soils under transition to environmental parameters. Our results also indicated that the long-term crop rotation modified the abundance of the investigated microbial groups compared to the monoculture and increased soil chemical and physical quality. Therefore, our results provide evidence for a stimulatory effect of the long-term crop rotation on the abundance of microbes involved in N transformation.

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The “black drop” phenomenon and reduction of the mercury transits observations

Symposium - International Astronomical Union ◽

10.1017/s007418090012786x ◽

1996 ◽

Vol 172 ◽

pp. 453-454

Author(s):

A.M. Sveshnikov ◽

M.L. Sveshnikov

Keyword(s):

Earth Rotation ◽

Visual Observation ◽

The Earth ◽

Long Term Variations

Mercury transits are important for the investigation of long-term variations in the Earth rotation. They have been observed for more than 300 years. The basic array of this set is the visual observation of contacts (as a rule the second and third ones). The detection of the instant corresponding to the geometrical contact of the solar and Mercury limbs is a difficult task, since during 10s to 60s, the set of phases is observed transforming continuously from one to another. One of the encumbering factors, is the so-called “black drop” phenomenon, i.e., the dark cross-bar formed between the limbs (Struve, 1882; Kuhl, 1929; Wittman, 1974; Morrison et al., 1975). The influence of this factor could be negleted if the observations were distributed uniformly with regard to contacts, observers and observational conditions. In fact, it is far from that and the necessity of reduction corrections arises.

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The Internal Connection Study of Graphics, Image and Virtual Realism

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.26-28.728 ◽

2010 ◽

Vol 26-28 ◽

pp. 728-731

Author(s):

De Fa Zhang

Keyword(s):

Mechanical Design ◽

New Technology ◽

Space Environment ◽

Automatic Production ◽

The Earth ◽

Virtual Laboratories ◽

Great Progress ◽

Automatic Production Line ◽

Relative Theory

With the development of times, industry has been making great progress, which varies from primitive manual labor to machines in the age of steam. Then, machines and factories have taken the place of more and more manual labors with the development of mechanical design and relative theory. However, it still fails to reach the stage of full automation. Owing to the birth of computer and development of artificial intelligence, the robot factory is no longer a fresh topic. Undoubtedly, those are linked with graphic and computer’s development. There must be a more advanced theory and technology coming into being as graphic & image reach a higher stage. Then, it was named as the virtual realism technology. This new technology has been widely applied to various fields, such as, automatic production line, air quality automatic detector, war-simulating in army, “simulating space environment” on the earth, virtual laboratories building in the education and etc. Now, here are two basic concepts involved in the long-term development: graphics and image.

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Sensitivity limit investigation of a Sagnac gyroscope through linear regression analysis

The European Physical Journal C ◽

10.1140/epjc/s10052-021-09199-1 ◽

2021 ◽

Vol 81 (5) ◽

Author(s):

Angela D. Di Virgilio ◽

Carlo Altucci ◽

Francesco Bajardi ◽

Andrea Basti ◽

Nicolò Beverini ◽

...

Keyword(s):

Rotation Rate ◽

Linear Regression Analysis ◽

Sensitivity Limit ◽

Angular Rotation ◽

Fundamental Physics ◽

Tests Of General Relativity ◽

The Earth ◽

Theoretical Investigations ◽

Sagnac Gyroscope

AbstractThe sensitivity to angular rotation of the top class Sagnac gyroscope GINGERINO is carefully investigated with standard statistical means, using 103 days of continuous operation and the available geodesic measurements of the Earth angular rotation rate. All features of the Earth rotation rate are correctly reproduced. The unprecedented sensitivity of fractions of frad/s is attained for long term runs. This excellent sensitivity and stability put Sagnac gyroscopes at the forefront for fundamental physics, in particular for tests of general relativity and Lorentz violation, where the sensitivity plays the key role to provide reliable data for deeper theoretical investigations.

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Hydrometeorology: Review of Past, Present and Future Observation Methods

10.5772/intechopen.94939 ◽

2020 ◽

Author(s):

Mohammad Valipour ◽

Sayed M. Bateni ◽

Nicolas R. Dalezios ◽

Mansour Almazroui ◽

Essam Heggy ◽

...

Keyword(s):

Numerical Models ◽

Environmental Parameters ◽

Weather Forecast ◽

The Earth ◽

Observation Methods ◽

Modeling And Forecasting ◽

Climate Evolution ◽

Modern Knowledge

Hydrometeorology aims at measuring and understanding the physics, chemistry, energy and water fluxes of the atmosphere, and their coupling with the earth surface environmental parameters. Accurate hydrometeorological records and observations with different timelines are crucial to assess climate evolution and weather forecast. Historical records suggest that the first hydrometeorological observations date back to ca 3500 BC. Reviewing these observations in the light of our modern knowledge of the dynamic of atmospheres is critical as it can reduce the ambiguities associated to understanding major fluctuations or evolutions in the earth climate. Today, the ambiguities in hydrometeorological observations have significantly improved due to the advances in monitoring, modeling, and forecasting of processes related to the land-atmosphere coupling and forcing. Numerical models have been developed to forecast hydrometeorological phenomena in short-, medium- and long-term horizons, ranging from hourly to annual timescales. We provide herein a synthetic review of advances in hydrometeorological observations from their infancy to today. In particular, we discuss the role of hydrometeorological records, observations, and modeling in assessing the amplitude and time-scale for climate change and global warming.

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All-nanofiber–based, ultrasensitive, gas-permeable mechanoacoustic sensors for continuous long-term heart monitoring

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1920911117 ◽

2020 ◽

Vol 117 (13) ◽

pp. 7063-7070 ◽

Cited By ~ 5

Author(s):

Md Osman Goni Nayeem ◽

Sunghoon Lee ◽

Hanbit Jin ◽

Naoji Matsuhisa ◽

Hiroaki Jinno ◽

...

Keyword(s):

Continuous Monitoring ◽

Signal To Noise Ratio ◽

Low Frequency ◽

High Sensitivity ◽

Frequency Region ◽

Sound Waves ◽

Signal To Noise ◽

Low Intensity ◽

Heart Monitoring

The prolonged and continuous monitoring of mechanoacoustic heart signals is essential for the early diagnosis of cardiovascular diseases. These bodily acoustics have low intensity and low frequency, and measuring them continuously for long periods requires ultrasensitive, lightweight, gas-permeable mechanoacoustic sensors. Here, we present an all-nanofiber mechanoacoustic sensor, which exhibits a sensitivity as high as 10,050.6 mV Pa−1 in the low-frequency region (<500 Hz). The high sensitivity is achieved by the use of durable and ultrathin (2.5 µm) nanofiber electrode layers enabling a large vibration of the sensor during the application of sound waves. The sensor is ultralightweight, and the overall weight is as small as 5 mg or less. The devices are mechanically robust against bending, and show no degradation in performance even after 1,000-cycle bending. Finally, we demonstrate a continuous long-term (10 h) measurement of heart signals with a signal-to-noise ratio as high as 40.9 decibels (dB).

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Estimating variations in Earth rotation using GPS, GLONASS, and Galileo

10.5194/egusphere-egu21-2646 ◽

2021 ◽

Author(s):

Radosław Zajdel ◽

Krzysztof Sośnica ◽

Grzegorz Bury ◽

Kamil Kazmierski

Keyword(s):

Earth Rotation ◽

High Frequency ◽

Low Frequency ◽

Earth’S Rotation ◽

Earth's Rotation ◽

The Earth ◽

Earth Rotation Parameters ◽

Space Geodetic Techniques ◽

Rotation Parameters ◽

Frequency Variations

Variations in the Earth's rotation can be examined in the low-frequency and high-frequency temporal scales. The low-frequency variations are dominated by the annual and Chandler wobbles, while the high-frequency variations are primarily caused by tidal effects and mass redistributions within the system Earth. Depending on the purpose, the Earth Rotation Parameters (ERPs) can be estimated in different time resolutions using space-geodetic techniques, especially using GNSS. However, the residual signals between different space geodetic techniques or satellite constellations indicate system-specific differences, which have to be correctly identified.This research provides the daily, and sub-daily series of Earth Rotation Parameters (ERPs) estimated using GPS, GLONASS, and Galileo observations. We test different sampling intervals of estimated ERPs from 1h to 24h. The GNSS-based sub-daily estimates have been compared with the external models of variations in ERPs induced by the ocean tides from the IERS 2010 Conventions, a new model by Desai-Sibois, and the VLBI-based model by Gipson.Any system-specific ERPs are affected by the orbital and draconitic signals. The orbital signals are visible in all system-specific ERPs at the periods that arise from the resonance between the Earth's rotation and the satellite revolution period, e.g., 8.87h, 34.22h, 3.4 days, 10 days for Galileo; 7.66h, 21.29h, 3.9 days, 7.9 days for GLONASS; 7.98h (S3 tidal term), 11.97h (S2 tidal term), 23.93h (S1 tidal term) for GPS. In the Galileo and GLONASS solutions, the artificial non-tidal signals' amplitudes can reach up to 30 &#181;as. The GPS-derived sub-daily ERPs suffer from the overlapping periods of the diurnal and semidiurnal tidal terms and the harmonics of the GPS revolution period. After recovery of 38 sub-daily tidal terms, the Galileo-based model is more consistent with the external models than the GPS-based model, especially in the prograde diurnal band. The results confirmed that the Desai&#8211;Sibois model is more consistent with GNSS observations than the currently recommended model by the IERS 2010 Conventions. Moreover, GPS-based length-of-day (LoD) is systematically biased with respect to the IERS-C04-14 values with a mean offset of &#8722;22.4 &#181;s/day, because of the deep resonance 2:1 between the satellite revolution period and the Earth rotation. The Galileo-based and GLONASS-based solutions are almost entirely free of this issue. Against the individual system-specific solutions, the multi-GNSS solution is not affected by most of the system-specific artifacts. Thus, multi-GNSS solutions are clearly beneficial for the estimation of both daily and sub-daily ERPs.

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The Earth angle moment balance, low-frequency atmospheric processes and radiowaveguides: ii. application of an advanced non-stationary theory for different forms of atmosphere circulation

Ukrainian hydrometeorological journal ◽

10.31481/uhmj.16.2015.11 ◽

2017 ◽

pp. 83-88

Author(s):

A.V. Glushkov ◽

A.А. Svinarenko ◽

S.V. Ambrosov ◽

Yu.Ya. Bunyakova ◽

V.V. Buyadzhi ◽

...

Keyword(s):

Angular Momentum ◽

Atmospheric Circulation ◽

Low Frequency ◽

Momentum Balance ◽

Atmospheric Moisture ◽

Atmospheric Processes ◽

The Earth ◽

Stationary Theory ◽

Long Term Forecasting

In the paper we present the results of application of a new advanced non-stationary theory of global mechanisms in atmospheric low-frequency processes, the balance of the angular momentum of the Earth, teleconnection effects and atmospheric radio waveguides, for the Pacific ocean region for different forms of the atmosphere circulation. The theory is realized and implemented into Microsystem Technology "GeoMath" and focused on the discovery and testing of new predictors for long-term and very long-forecasts of low-frequency atmospheric processes. The PC experiments have demonstrated an effectiveness of a new advanced theory in application to modeling balance of angular momentum, the atmospheric moisture turnover in relation to the genesis of tropospheric radio waveguides and succession processes of atmospheric circulation forms (teleconnection, front-genesis) in order to develop new practical sensors in long-term forecasting and modeling of low-frequency atmospheric processes. It is determined a link of tropospheric waveguide with atmospheric moisture circulation and, accordingly, with the shape of the atmospheric circulation over the position of the front sections of (atmospheric fronts as the main drives moisture). Atmospheric moisture cycle is linked with such typical low-frequency process as the angular momentum balance; the latter accounts violation of the atmosphere rotating balance with the Earth.

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