DETERMINATION OF THE BEST PROBABILITY DISTRIBUTION OF FIT FOR OZONE CONCENTRATION DATA IN CAMPO GRANDE-MS-BRAZIL

2019 ◽  
Vol 8 (9) ◽  
pp. 291
Author(s):  
Amaury De Souza ◽  
Bulbul Jan ◽  
Faisal Nawaz ◽  
Muhamamd Ayub Khan Yousuf Zai ◽  
Soetania Santos De Oliviera ◽  
...  
Keyword(s):  
Probability Distribution ◽  
Ozone Concentration ◽  
Concentration Data

Determination of the Probability Distribution of the Mean Sound Level

2010 ◽  
Vol 35 (4) ◽  
pp. 543-550 ◽  
Author(s):  
Wojciech Batko ◽  
Bartosz Przysucha
Keyword(s):  
Probability Distribution ◽  
Probability Distribution Function ◽  
Mean Value ◽  
Sound Level ◽  
Function Form ◽  
Noise Levels ◽  
Logarithmic Mean ◽  
The Mean ◽  
Estimation Of Uncertainty

AbstractAssessment of several noise indicators are determined by the logarithmic mean <img src="/fulltext-image.asp?format=htmlnonpaginated&src=P42524002G141TV8_html\05_paper.gif" alt=""/>, from the sum of independent random resultsL1;L2; : : : ;Lnof the sound level, being under testing. The estimation of uncertainty of such averaging requires knowledge of probability distribution of the function form of their calculations. The developed solution, leading to the recurrent determination of the probability distribution function for the estimation of the mean value of noise levels and its variance, is shown in this paper.

scholarly journals Drawing transmission graphs for COVID-19 in the perspective of network science

2020 ◽  
Vol 148 ◽  
Author(s):  
N. Gürsakal ◽  
B. Batmaz ◽  
G. Aktuna
Keyword(s):  
Probability Distribution ◽  
Network Science ◽  
Pareto Distribution ◽  
Transmission Probability ◽  
Transmission Network ◽  
Pareto Principle ◽  
Infected People ◽  
Discrete Pareto Distribution ◽  
Local Transmission

Abstract When we consider a probability distribution about how many COVID-19-infected people will transmit the disease, two points become important. First, there could be super-spreaders in these distributions/networks and second, the Pareto principle could be valid in these distributions/networks regarding estimation that 20% of cases were responsible for 80% of local transmission. When we accept that these two points are valid, the distribution of transmission becomes a discrete Pareto distribution, which is a kind of power law. Having such a transmission distribution, then we can simulate COVID-19 networks and find super-spreaders using the centricity measurements in these networks. In this research, in the first we transformed a transmission distribution of statistics and epidemiology into a transmission network of network science and second we try to determine who the super-spreaders are by using this network and eigenvalue centrality measure. We underline that determination of transmission probability distribution is a very important point in the analysis of the epidemic and determining the precautions to be taken.

NaCl and CaCl2 activity coefficients in mixed aqueous solutions

1965 ◽  
Vol 20 (6) ◽  
pp. 1332-1336 ◽  
Author(s):  
Edward W. Moore ◽  
James W. Ross
Keyword(s):  
Ionic Strength ◽  
Activity Coefficients ◽  
Technical Assistance ◽  
Osmotic Coefficients ◽  
Electrode System ◽  
Glass Electrode ◽  
Concentration Data ◽  
Harned's Rule ◽  
Potentiometric Measurement

In the investigation of numerous physiological phenomena it is the activity of an ion species which is desired, rather than stoichiometric concentration. The calculation of mean ionic activity from known concentration data requires accurate activity coefficients (ggr). This report concerns the determination of ggrNaCl and ggrCaCl2 in mixed NaCl-CaCl2 solutions by potentiometric measurement with a sodium-selective glass electrode-Ag/AgCl electrode system over the ionic strength range 0.05–0.5 m. Log ggrNaCl varied linearly, at constant total ionic strength, with the ionic strength of CaCl2 in the mixture, in accordance with Harned's rule. From data thus obtained, ggrCaCl2 coefficients in such mixed solutions have been calculated and compared with values calculated from published osmotic data. Resulting activity coefficient curves for ggrCaCl2 are presented over the concentration range encountered in serum and other extracellular fluids. Note: (With the Technical Assistance of Leonard Kaye and Leonard L. Anderson) glass electrodes; ion interaction; electrolyte metabolism; Harned's rule; membrane transport; osmotic coefficients Submitted on March 11, 1965

Development and Validation of Chemometric-Assisted Spectrophotometric Methods for Simultaneous Determination of Phenylephrine Hydrochloride and Ketorolac Tromethamine in Binary Combinations

2016 ◽  
Vol 99 (5) ◽  
pp. 1247-1251 ◽  
Author(s):  
Hamed M Elfatatry ◽  
Mokhtar M Mabrouk ◽  
Sherin F Hammad ◽  
Fotouh R Mansour ◽  
Amira H Kamal ◽  
...  
Keyword(s):  
Least Squares ◽  
Simultaneous Determination ◽  
Principal Component Regression ◽  
Principal Component ◽  
Data Matrix ◽  
Ketorolac Tromethamine ◽  
Concentration Data ◽  
Phenylephrine Hydrochloride ◽  
Spectrophotometric Methods

Abstract The present work describes new spectrophotometric methods for the simultaneous determination of phenylephrine hydrochloride and ketorolac tromethamine in their synthetic mixtures. The applied chemometric techniques are multivariate methods including classical least squares, principal component regression, and partial least squares. In these techniques, the concentration data matrix was prepared by using the synthetic mixtures containing these drugs dissolved in distilled water. The absorbance data matrix corresponding to the concentration data was obtained by measuring the absorbances at 16 wavelengths in the range 244–274 nm at 2 nm intervals in the zero-order spectra. The spectrophotometric procedures do not require any separation steps. The accuracy, precision, and linearity ranges of the methods have been determined, and analyzing synthetic mixtures containing the studied drugs has validated them. The developed methods were successfully applied to the synthetic mixtures and the results were compared to those obtained by a reported HPLC method.

scholarly journals Liquid Chromatographic and Spectrophotometric Determination of Diflucortolone Valerate and Isoconazole Nitrate in Creams

2011 ◽  
Vol 94 (1) ◽  
pp. 128-135 ◽  
Author(s):  
Elif Karacan ◽  
Mehmet Gokhan Çaġlayan ◽  
İsmail Murat Palabiyik ◽  
Feyyaz Onur
Keyword(s):  
Principal Component Regression ◽  
Principal Component ◽  
Derivative Spectrophotometry ◽  
Data Matrix ◽  
Concentration Data ◽  
Spectrophotometric Methods ◽  
First Derivative ◽  
First Derivative Spectrophotometry ◽  
Liquid Chromatographic

Abstract A new RP-LC method and two new spectrophotometric methods, principal component regression (PCR) and first derivative spectrophotometry, are proposed for simultaneous determination of diflucortolone valerate (DIF) and isoconazole nitrate (ISO) in cream formulations. An isocratic system consisting of an ACE® C18 column and a mobile phase composed of methanol–water (95+5, v/v) was used for the optimal chromatographic separation. In PCR, the concentration data matrix was prepared by using synthetic mixtures containing these drugs in methanol–water (3+1, v/v). The absorbance data matrix corresponding to the concentration data matrix was obtained by measuring the absorbances at 29 wavelengths in the range of 242–298 nm for DIF and ISO in the zero-order spectra of their combinations. In first derivative spectrophotometry, dA/dλ values were measured at 247.8 nm for DIF and at 240.2 nm for ISO in first derivative spectra of the solution of DIF and ISO in methanol–water (3+1, v/v). The linear ranges were 4.00–48.0 μg/mL for DIF and 50.0–400 μg/mL for ISO in the LC method, and 2.40–40.0 μg/mL for DIF and 60.0–260 μg/mL for ISO in the PCR and first derivative spectrophotometric methods. These methods were validated by analyzing synthetic mixtures. These three methods were successfully applied to two pharmaceutical cream preparations.

Determination of Indoor 222Rn Concentrations Level on Different Room Sizes in Academic Building at Universiti Malaysia Kelantan Jeli Campus

2017 ◽  
Vol 888 ◽  
pp. 447-452 ◽  
Author(s):  
Mohammad Khairul Azhar Abdul Razab ◽  
Nur Liyana Hamzah ◽  
Siti Fatimah Abd Karim ◽  
Nur Ezati Azhar ◽  
Nor Hakimin Abdullah ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Pearson Correlation ◽  
Concentration Data ◽  
Radon Monitor ◽  
Temperature And Pressure ◽  
Academic Building

The objectives of this study are to briefly monitor the 222Rn concentration in selected study area and to investigate its correlation with the environmental factors (pressure, humidity and temperature). 222Rn concentrations were monitored in three different sizes of lecture rooms known as BK 6, BK 7 and BK 8 at academic building, Universiti Malaysia Kelantan (UMK) Jeli Campus. Radon monitor known as Sentinel 1030 has been used to collect 210 readings of 222Rn concentration data. Environmental factors for each study areas was analyzed by using Pearson correlation. The average 222Rn concentrations for BK 6, BK 7 and BK 8 were found at 0.29 pCi/L, 0.31 pCi/L and 0.72 pCi/L, respectively. BK 8 with 277.97 m³ obtained higher 222Rn concentrations than BK 6 with 440.98 m³, followed by BK 7 with 292.67 m³. From the results, 222Rn concentration in BK 6 and BK 7 are influenced by temperature and pressure, correspondingly. However, no correlation of environmental factors found in BK 8.

Occurrence of discontinuities in the ozone concentration data from three reanalyses

2020 ◽  
Author(s):  
Peter Krizan ◽  
Michal Kozubek ◽  
Jan Lastovicka
Keyword(s):  
Time Evolution ◽  
Southern Hemisphere ◽  
Ozone Concentration ◽  
Temporal Structure ◽  
The Other ◽  
Trace Gas ◽  
Homogeneity Test ◽  
Concentration Data ◽  
Ozone Data ◽  
Ozone Trend

Abstract. Ozone is a very important trace gas in the stratosphere and thus we need to know its time evolution over the globe. The ground based measurements are rare, especially in the Southern Hemisphere. Satellite ozone data have broader coverage, but they are not available from everywhere. On the other hand, the reanalyse data have regular spatial and temporal structure, which is very good for trend analyses. But there are discontinuities in these data.These discontinuities may influence the result of trend studies. The aim of this paper is to detect the discontinuity occurrence (DO) in the following reanalyses: MERRA-2, ERA-5 and JRA-55 with the help of the Pettitt homogeneity test at all common layers above 500 hPa. The discontinuities are sorted according to their size to the significant and the insignificant ones; the former can affect the ozone trend studies. It was shown that DO for the significant discontinuities is the smallest in JRA-55. In the upper model layers, the discontinuity occurrence is the highest. The other area of high DO is the troposphere.

scholarly journals Benchmark of Nanoparticle Tracking Analysis on Measuring Nanoparticle Sizing and Concentration

2017 ◽  
Vol 5 (4) ◽  
Author(s):  
Ciarán M. Maguire ◽  
Katherine Sillence ◽  
Matthias Roesslein ◽  
Claire Hannell ◽  
Guillaume Suarez ◽  
...  
Keyword(s):  
Interlaboratory Comparison ◽  
Track Length ◽  
Nanoparticle Tracking Analysis ◽  
Concentration Data ◽  
Liquid Suspension ◽  
Coefficients Of Variation ◽  
Multiple Sample ◽  
Research Facilities

One of the greatest challenges in the manufacturing and development of nanotechnologies is the requirement for robust, reliable, and accurate characterization data. Presented here are the results of an interlaboratory comparison (ILC) brought about through multiple rounds of engagement with NanoSight Malvern and ten pan-European research facilities. Following refinement of the nanoparticle tracking analysis (NTA) technique, the size and concentration characterization of nanoparticles in liquid suspension was proven to be robust and reproducible for multiple sample types in monomodal, binary, or multimodal mixtures. The limits of measurement were shown to exceed the 30–600 nm range (with all system models), with percentage coefficients of variation (% CV) being calculated as sub 5% for monodisperse samples. Particle size distributions were also improved through the incorporation of the finite track length adjustment (FTLA) algorithm, which most noticeably acts to improve the resolution of multimodal sample mixtures. The addition of a software correction to account for variations between instruments also dramatically increased the accuracy and reproducibility of concentration measurements. When combined, the advances brought about during the interlaboratory comparisons allow for the simultaneous determination of accurate and precise nanoparticle sizing and concentration data in one measurement.

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