Variabilidade temporal dos fluxos noturnos determinados a partir de duas diferentes metodologias no nível de 325 m acima da floresta Amazônica

The present study aimed to analyze and compare the temporal variability of the nocturnal fluxes of CO2, sensitive and latent heat, calculated from two different methodologies: one with a 5-minute temporal window (using the eddy covariance technique), and another with 109 minutes (from multiresolution decomposition). For this, night series of 25 nights were used between October and November 2015. The analyzes were made for two groups of distinct turbulence patterns: one with intermittent regime and the other with homogeneous turbulence. The results showed that the fluxes obtained by the classical method of eddy covariance were dependent on the intensity of the turbulence. On the other hand, the fluxes calculated from the multiresolution decomposition technique showed significant fluctuations in the temporal evolution of all scalars analyzed, with the largest percentage differences between the two approaches occurring in the homogeneous turbulence regime group, which was characterized by predominantly weak turbulent activity throughout the night. In the comparison made, the methodology employed in the 109-minute window showed greater efficiency in the estimates of exchanges at 325 m in the ATTO tower, especially during conditions of low turbulent activity.

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Temporal variability of disinfection by-products concentration in urban public water system

Global NEST Journal ◽

10.30955/gnj.000902 ◽

2013 ◽

Vol 14 (4) ◽

pp. 393-398

Keyword(s):

Drinking Water ◽

Water Samples ◽

Temporal Variability ◽

Water System ◽

The Other ◽

Major Constituent ◽

System P ◽

Public Water System ◽

Drinking Water Samples ◽

By Products

The occurrence of trihalomethanes (THMs) was studied in the drinking water samples from urban water supply network of Karachi city that served more than 18 million people. Drinking water samples were collected from 58 locations in summer (May-August) and winter (November-February) seasons. The major constituent of THMs detected was chloroform in winter (92.34%) and summer (93.07%), while the other THMs determined at lower concentrations. Summer and winter concentrations of total THMs at places exceed the levels regulated by UEPA (80 μg l-1) and WHO (100 μg l-1). GIS linked temporal variability in two seasons showed significantly higher median concentration (2.5%-23.06%) of THMs compared to winter.

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Multifrequency Variability of AGN's: Continuum Variations from the Near IR to the X-rays

Symposium - International Astronomical Union ◽

10.1017/s0074180900174923 ◽

1994 ◽

Vol 159 ◽

pp. 131-143

Author(s):

J. Clavel

Keyword(s):

Active Galactic Nuclei ◽

Temporal Evolution ◽

Line Emission ◽

Galactic Nuclei ◽

The Other ◽

X Rays ◽

Optical Telescope ◽

Emission Process ◽

Near Ir ◽

The Continuum

Because they emit copiously over more than 10 decades in frequency, Active Galactic Nuclei (AGN) cannot be understood without the help of multiwavelength observations. On the other hand, variability monitoring has also proven to be invaluable in understanding the continuum and line emission process as well as the geometry of the innermost regions in these objects. Indeed, at the heart of AGN's lies an object which is so compact that the only way to probe its structure is the study of the temporal evolution of its spectrum. The equivalent resolution which can be achieved in this way is of the order of 10 microarcsecs, far beyond the capability of any UV or optical telescope.

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Magnetoresistance, temporal evolution, and relaxation of the electrical resistivity in the re-entrant semiconducting La0.80Ba0.20CoO3 perovskite

Journal of Materials Research ◽

10.1557/jmr.1999.0339 ◽

1999 ◽

Vol 14 (6) ◽

pp. 2533-2539 ◽

Cited By ~ 4

Author(s):

R. D. Sánchez ◽

J. Mira ◽

J. Rivas ◽

M. P. Breijo ◽

M. A. Señarís-Rodríguez

Keyword(s):

Magnetic Properties ◽

Electrical Resistivity ◽

Temporal Evolution ◽

The Other ◽

Inhomogeneous System ◽

Metal Insulator ◽

Relaxation Effects ◽

Electrical And Magnetic Properties ◽

Semiconducting Behavior ◽

Insulator Sequence

We report here a study on the electrical and magnetic properties of La1−xBaxCoO3 in the re-entrant semiconducting region (x = 0.20). We find that in this material: (i) the insulator-metal-insulator sequence is unstable and evolves toward a purely semiconducting behavior; the initial r versus T curve can be reinstated upon appropriate annealing treatments; (ii) there are relaxation effects that can be seen by changing the polarity of the electrodes; (iii) there is a negative magnetoresistance Δρ/ρ ∼ 2–3%, for a field as low as 9 kOe, especially at the metal-insulating transition temperatures; and (iv) there are important fluctuations in the electrical resistivity. Taking into account these experimental observations, we can interpret this material as an inhomogeneous system where two thermodynamic phases, one semiconducting and the other metallic and ferromagnetic, coexist, although they are crystallographically indistinguishable.

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A Comparison of Three Gap Filling Techniques for Eddy Covariance Net Carbon Fluxes in Short Vegetation Ecosystems

Advances in Meteorology ◽

10.1155/2015/260580 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 8

Author(s):

Xiaosong Zhao ◽

Yao Huang

Keyword(s):

Time Series ◽

Standard Deviation ◽

Diurnal Variation ◽

Eddy Covariance ◽

Nonlinear Regression ◽

Missing Values ◽

The Other ◽

Gap Filling ◽

Benchmark Datasets ◽

Filling Method

Missing data is an inevitable problem when measuring CO2, water, and energy fluxes between biosphere and atmosphere by eddy covariance systems. To find the optimum gap-filling method for short vegetations, we review three-methods mean diurnal variation (MDV), look-up tables (LUT), and nonlinear regression (NLR) for estimating missing values of net ecosystem CO2exchange (NEE) in eddy covariance time series and evaluate their performance for different artificial gap scenarios based on benchmark datasets from marsh and cropland sites in China. The cumulative errors for three methods have no consistent bias trends, which ranged between −30 and +30 mgCO2 m−2from May to October at three sites. To reduce sum bias in maximum, combined gap-filling methods were selected for short vegetation. The NLR or LUT method was selected after plant rapidly increasing in spring and before the end of plant growing, and MDV method was used to the other stage. The sum relative error (SRE) of optimum method ranged between −2 and +4% for four-gap level at three sites, except for 55% gaps at soybean site, which also obviously reduced standard deviation of error.

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It's about Time: The Temporal Evolution of Order

Theatre Research International ◽

10.1017/s0307883309004465 ◽

2009 ◽

Vol 34 (2) ◽

pp. 131-137

Author(s):

MOSHE PERLSTEIN

Keyword(s):

Temporal Evolution ◽

Second Law Of Thermodynamics ◽

The Other ◽

Second Law ◽

Ethical Values ◽

Other Hand ◽

Measure For Measure ◽

Analyse Time

This article borrows its methodology from physics in order to analyse time in the theatre as evolution of order. Two set designs (both designed by Roni Toren for the Khan Theatre in Jerusalem) are portrayed through this perspective, representing inverse examples. In Measure for Measure, directed by Gadi Roll, the temporal evolution of space is from order to disorder, obeying the second law of thermodynamics. On the other hand, in The Seagull, directed by Ofira Henig, the evolution contradicts that law. The problem of depicting disorder on stage, the possibility of such a contradiction, the implication of the two different perceptions and their ethical values are discussed to prove the effectiveness of a methodology adopted from physics.

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Value Analysis and TRIZ - A Methodology for Innovative Economics and Technical Solutions

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.809-810.1535 ◽

2015 ◽

Vol 809-810 ◽

pp. 1535-1540

Author(s):

Gabriela Mariana Ionescu

Keyword(s):

Classical Method ◽

The Other ◽

Current Interest ◽

Value Analysis ◽

Research Activities ◽

Wide Debate ◽

Technical Solutions ◽

Managerial Innovation ◽

Business And Management ◽

Management Domains

This paper presents a new methodology entitled AVTRIZ by its author, which allows technical, economic and managerial innovation based on the forecasting approach, while operating inside various systems. As the foundation of the new methodology, a classical method was chosen, well-known and widely applied that is the Method of Value Analysis and Engineering, a domain where the author has previous concerns. Starting from the fact that this method is deficient in terms of generating improvement solutions, the author searched and identified a method of current interest and global opportunity that is the TRIZ method [1], which is a method of wide debate, very controversial in terms of its adaptability from the technical to the business and management domains. On the other hand, TRIZ is deficient in terms of checking the solutions, a fact which can be successfully compensated by the Value Analysis Engineering method. Based on the above-mentioned approach, the research activities carried out by the author have brought in a new methodology, which is structured on 3 steps, 8 stages and 30 phases, based on the method of Value Analysis and Engineering, while also applying the TRIZ method.

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A Long Term (2005–2019) Eddy Covariance Data Set of CO<sub>2</sub> and H<sub>2</sub>O Fluxes from the Tibetan Alpine Steppe

10.5194/essd-2020-63 ◽

2020 ◽

Author(s):

Felix Nieberding ◽

Cristian Wille ◽

Gerardo Fratini ◽

Magnus O. Asmussen ◽

Yuyang Wang ◽

...

Keyword(s):

Eddy Covariance ◽

Field Analysis ◽

Climate Feedback ◽

The Tibetan Plateau ◽

Data Set ◽

Alpine Steppe ◽

Turbulence Regime ◽

Tibet Autonomous Region ◽

Steppe Ecosystem ◽

Carbon Dioxide Co2

Abstract. The Tibetan alpine steppe ecosystem covers an area of roughly 800,000 km2, containing up to 3.3 % soil organic carbon in the uppermost 30 cm, summing up to 1.93 PgvC for the Tibet Autonomous Region only (472,037 km2). With temperatures rising two to three times faster than the global average, these carbon stocks are at risk of loss due to enhanced soil respiration. The remote location and the harsh environmental conditions on the Tibetan Plateau (TP) make it challenging to derive accurate data on ecosystem-atmosphere exchange of carbon dioxide (CO2) and water vapor (H2O). Here, we provide the first multi-year data set of CO2 and H2O fluxes from the central Tibetan alpine steppe ecosystem, measured in situ using the eddy covariance technique. The calculated fluxes were rigorously quality checked and carefully corrected for a drift in concentration measurements and gas analyzer self heating during cold conditions. A wind field analysis was conducted to identify influences of adjacent buildings on the turbulence regime and to exclude the disturbed fluxes from subsequent computations. The presented CO2 fluxes were additionally gap filled using a standardized approach. The very low net carbon uptake across the 15-year data set highlights the special vulnerability of the Tibetan alpine steppe ecosystem to become a source of CO2 due to global warming. The data is freely available (https://www.doi.org/10.5281/zenodo.3733203, Nieberding et al., 2020b) and may help to better understand the role of the Tibetan alpine steppe in the global carbon-climate feedback.

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Prediction of the propagation of SARS-CoV-2 in Amapá State, Amazon Region, Brazil, by mathematical modeling

Panorama brasileiro de tungstênio (w) entre os anos de 2008 e 2014 ◽

10.32749/nucleodoconhecimento.com.br/health/prediction-of-the-propagation ◽

2020 ◽

pp. 73-95

Author(s):

Neylan Leal Dias ◽

Edcarlos Vasconcelos da Silva ◽

Marcelo Amanajas Pires ◽

Daniel Chaves ◽

Katsumi Letra Sanada ◽

...

Keyword(s):

Mathematical Modeling ◽

Temporal Evolution ◽

Sir Model ◽

Amazon Region ◽

The Other ◽

Short Term ◽

Exponential Behavior ◽

Linear Projection ◽

The Third ◽

The One

This article presents an analysis of the spread of SARS-CoV-2 in Amapá using three approaches. In the first, the ICL model for the pandemic applied to Brazil was used to implement a comparative linear projection for the Amapá population. The second approach was developed with the short-term solution of the standard SIR model where it was shown that the typical exponential behavior satisfactorily describes the data for the first weeks of the epidemic, but soon after there are early discrepancies due to a sudden slowdown in the temporal evolution number of cases due to isolation measures. This new regime is appropriately described with the third approach which is based on the vSIR model which is a variant of the SIR model. The results presented enable, on the one hand, a better understanding of the scenarios already faced by the population and on the other hand provide short-term projections that will be constantly updated on the link[11].

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Natural Changes in a Soil of the Mediterranean Climate Under Low Agronomic Inputs

10.20944/preprints202105.0610.v1 ◽

2021 ◽

Author(s):

Antonietta Napolitano ◽

Luigi Santonicola

Keyword(s):

Organic Matter ◽

Sandy Soil ◽

Temporal Variability ◽

Mediterranean Climate ◽

Bare Soil ◽

Great Variability ◽

The Other ◽

Cyclical Pattern ◽

Different Seasons ◽

Set Up

: This study was conducted to evaluate the behavior of nitrate, moisture and organic matter in a soil with low agronomic input. The test was conducted on silty-sandy soil, a temporal variability of the variables in the different seasons was observed in the three theses. The theses were observed in parallel twice a week. Nitrates showed an increase during the summer-autumn season with higher values in the thesis containing organic matter, “bare soil” followed by the thesis “fallow” and finally by the “cultivated” (see below in experimental set up). The humidity was higher in the “bare soil” thesis followed by “fallow” and “cultivated” one during the summer, in winter the “cultivated” showed the lowest humidity compared to the other two theses. The organic matter does not show great variability in the seasons but is higher in the “fallow” thesis followed by “bare soil” and “cultivated” one. The Montecarlo test informed us that organic matter and humidity were autocorrelated within 5-7.5 m of distance (10-15 lag) while nitrates even if they seemed to be not autocorrelated with each other and have a cyclical pattern.

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An experimental quantum Bernoulli factory

Science Advances ◽

10.1126/sciadv.aau6668 ◽

2019 ◽

Vol 5 (1) ◽

pp. eaau6668 ◽

Cited By ~ 1

Author(s):

Raj B. Patel ◽

Terry Rudolph ◽

Geoff J. Pryde

Keyword(s):

Stochastic Processes ◽

Quantum Coherence ◽

Classical Method ◽

The Other ◽

Concerted Effort ◽

Single Qubit ◽

Quantum Technology

There has been a concerted effort to identify problems computable with quantum technology, which are intractable with classical technology or require far fewer resources to compute. Recently, randomness processing in a Bernoulli factory has been identified as one such task. Here, we report two quantum photonic implementations of a Bernoulli factory, one using quantum coherence and single-qubit measurements and the other one using quantum coherence and entangling measurements of two qubits. We show that the former consumes three orders of magnitude fewer resources than the best-known classical method, while entanglement offers a further fivefold reduction. These concepts may provide a means for quantum-enhanced performance in the simulation of stochastic processes and sampling tasks.

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