Determination of the optimal periodicity of technical influence on restorable objects on the basis of weighted average probability of the machine failure

K, L and M shell x-ray fluorescence cross sections have been measured for elements 11 ≤, Z ≤, 92 at excitation energies corresponding to weighted average energies of K-lines of Ti-K (4.558 keV), Fe-K (6,480 keV), Ge-K (10.024 keV), Se-K (11.391 keV) and Mo-K (17.805 keV) . The measurements were performed with an energy-dispersive x-ray spectrometer in a vacuum chamber using thin ultra-pure targets. Rh x-ray tube and secondary targets were used for excitation of x-ray radiation. The measured x-ray fluorescence cross-sections have been compared to previously published experimental and theoretical results. Presented data can be used for determination of physical parameters such as photoionization cross-sections, fluorescence yields, x-ray emission rates, Coster-Kronig transition probabilities and jump ratios.

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Calculation and Prediction of the Total Glacial Melting in Watersheds of Central Asia

Journal of Glaciology ◽

10.3189/s0022143000029658 ◽

1977 ◽

Vol 19 (81) ◽

pp. 677-678

Author(s):

V.G. Konovalov

Keyword(s):

Solar Radiation ◽

Atmospheric Precipitation ◽

Weighted Average ◽

Total Solar Radiation ◽

Glacier Area ◽

Glacier Surface ◽

Seasonal Snow ◽

Glacier Terminus ◽

Snow Line

AbstractA computer method for calculating the total melting from May to October has been developed both for a single glacier and for a glacial area. In the second case (which is the more interesting and important for hydrology and glaciology) it is necessary to calculate some characteristics of an “average" glacier of the region using morphometric characteristics included in the Catalogue of the U.S.S.R. glaciers. These are: glacier area; average area of moraine on the glacier; weighted average of heights of upper and lower ends of a glacier and weighted average of mean height of firn line. It is also necessary to obtain data on glacier area distribution by height, precipitation data, and data on air temperature and cloudiness at meteorological stations.In addition to defining typical glacial regions within the limits of the glacial area considered and determination of the “average" glacier characteristics listed above, preparation of the computer programme includes (a) definition of precipitation dependence on orography height and calculation of appropriate parameters, (b) reduction (if necessary) of data obtained from the meteorological station nearest to glacial area to a more prolonged range, (c) calculation of a special balance index of accumulation and melting of seasonal precipitation which makes it possible to define maximum excess of seasonal snow line over the “average" glacier terminus in separate years, and (d) computation of total solar radiation occuring in clear days during May to October.In the course of computation on computer the following operations are realized: (a) determination of an average value of total radiation arriving during months of May to October period given the real cloudiness conditions, (b) calculation of the height of the snow line on the glacier, (c) calculation of quantity and duration of solid atmospheric precipitation which melts between May and October on the glacier surface, (d) estimation of absorbed solar radiation taking account of the differing albedo of glacial surfaces situated above and below the seasonal snow line, (e) calculation of the total melting of glaciers belonging to the given mountain watershed.Checking of the calculational method has been performed using data from Lednik Tsentralnyy Tuyuksu and Lednik Ayutor-2 where numerous ablation stakes were installed. Values of measured and calculated melting agree satisfactorily.

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Expert Approaches to the Assessment of Losartan Drugs Bioequivalence

The Bulletin of the Scientific Centre for Expert Evaluation of Medicinal Products ◽

10.30895/1991-2919-2020-10-1-51-62 ◽

2020 ◽

Vol 10 (1) ◽

pp. 51-62

Author(s):

D. P. Romodanovsky ◽

D. V. Goryachev

Keyword(s):

Retrospective Analysis ◽

Antihypertensive Drugs ◽

Weighted Average ◽

Individual Variability ◽

Pharmacokinetic Parameters ◽

Angiotensin Ii Receptor ◽

Russian Market ◽

Men And Women ◽

Starting Compound

Angiotensin II receptor antagonists (ARAs) are one of the most promising classes of antihypertensive drugs. They are most widely represented on the Russian market by losartan drugs which total 24 items. Therefore, it is crucial to analyse the factors that may affect the results of comparison of generic and reference losartan drugs.The aim of the study was to perform a retrospective analysis of bioequivalence studies of generic losartan drugs in order to develop approaches to expert evaluation of research protocols and reports.Materials and methods: the retrospective analysis covered the results of 27 bioequivalence studies of losartan and included the calculation of the pharmacokinetic parameters Cmax and AUC0-t, their intra-individual variability, and the weighted average of intra-individual variability. The calculations were made for the pooled population of men and women, as well as separately for each gender.Results: the data obtained indicate borderline high variability of losartan in bioequivalence studies (for Cmax in 50 % of the studies). It was demonstrated that losartan drugs may have different pharmacokinetics in men and women in terms of Cmax and AUC0-t. The retrospective analysis of the data made it possible to formulate relevant expert approaches to evaluation of protocols and reports of bioequivalence studies of losartan drugs.Conclusions: Bioequivalence of losartan should be evaluated in three- or four-period, double crossover, two-sequence replicate design studies. The study has to determine the pharmacokinetic parameters of the starting compound and its active metabolite; the period of determination of analytes should be at least 36 hours; the washout period of 7 days is sufficient; blood sampling should be more frequent during the first hour after administration for losartan and during the first 3–4 hours for the metabolite. When determining the sample size, the weighted average of the coefficient of intra-individual variability of Cmax of losartan (33 %) should be taken into account. The bioequivalence margins for Cmax can be scaled up.

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Determination of Reservoir Properties of Gas Layers under Conditions of Creep of Rocks with the Kernel of Abel

Oil and Gas technologies ◽

10.32935/1815-2600-2021-133-2-31-33 ◽

2021 ◽

Vol 133 (2) ◽

pp. 31-33

Author(s):

B. Z. Kazymov ◽

◽

Т. А. Samadov ◽

S. H. Novruzova ◽

E. V. Gadashova ◽

...

Keyword(s):

Finite Difference ◽

Finite Difference Method ◽

Numerical Solution ◽

Difference Method ◽

Weighted Average ◽

Reservoir Properties ◽

Reservoir Volume ◽

The Finite Difference Method ◽

Over Time

The problem of determining reservoir properties (porosity, permeability) of gas layers developed in the depletion mode, whose rocks are subjected to creeping deformation with the Abel core, is considered. In order to determine the parameters that characterize reservoir properties of the reservoir, the authors indicate the possibility of using an appropriate numerical solution to the problem of determining the theoretical values of the reservoir volume-weighted average reservoir pressures over time, obtained using the finite difference method.

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Chemical composition and age of monazite-(Ce) in granitoids of the crystalline basement from the South Yamal

News of the Ural State Mining University ◽

10.21440/2307-2091-2020-4-28-34 ◽

2020 ◽

pp. 28-34

Author(s):

Vera Vitalievna KHILLER ◽

Keyword(s):

Chemical Composition ◽

Weighted Average ◽

Crystalline Basement ◽

Beam Diameter ◽

Work Study ◽

The South ◽

Electron Probe Microanalyzer ◽

Chemical Dating ◽

Electron Beam Diameter

The relevance of the work is due to the need to improve the method of chemical dating as applied to high-thorium accessory minerals, which are difficult to date by isotope research methods. Purpose of the work: study of the chemical composition of accessory monazite from granitoids of the crystalline basement of the South Yamal and determination of its age. Research methodology: quantitative analysis of the chemical composition of monazite was carried out using X-ray spectral electron probe microanalyzer CAMECA SX 100 (electron beam diameter from 1 μm, BSE, SE, Cat modes, determination of elements from beryllium to uranium). The spectra were obtained with the help of inclined wave spectrometers, the intensity was measured using analytical lines: Th Ma, U Mb, Pb Ma, Y La, Si Ka, Ca Ka, P Ka, Ce La, La La, Pr Lb, Nd La, Sm Lb, Dy La, Gd Lb. The age calculation was carried out according to the well-known methods of foreign authors in addition to some developments of the author. Results. The chemical composition of monazite makes it possible to classify it as a cerium variety, the content of radiogenic components varies greatly (in wt.%): ThO2 – 5.37–16.31, UO2 – 0.40–0.81, PbO – 0.08–0,19. There are significant concentrations of SiO2 (up to 3.5 wt.%), Y2 O3 (up to 1.8 wt.%) and CaO (up to 1.2 wt.%). It turns out that monazite implements hattonite (Th4+(U4+)+Si4+ → REE3++P5+) and cheralite (Th4+(U4+)+Ca2+(Sr2+,Ba2+,Pb2+) → 2REE3+) isomorphism types. The decent content of lead and high crystallinity of the substance makes it possible to use this mineral as a geochronometer mineral. Conclusions. New data on the chemical composition of monazite have been obtained, and the late Permian age of granitoids has been determined by microprobe dating. The values of the point U–Th–Pb ages of monazite together give a weighted average age of 256 ± 10 Ma (MSWD = 0.15) and an isochron of 254 ± 19 Ma (MSWD = 0.28), which almost ideally coincides with the results of isotopic U–Pb zircon dating from the same rock, 254 ± 3 Ma.

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Comment on ‘Determination of the Radiocarbon Age of Parchment of the Vinland Map’

Radiocarbon ◽

10.1017/s0033822200031957 ◽

2002 ◽

Vol 44 (2) ◽

pp. 597-598

Author(s):

K R Ludwig

Keyword(s):

Weighted Average ◽

Weighted Mean ◽

Radiocarbon Age ◽

Chemical Treatments ◽

Statistical Errors

I wish to point out some statistical errors in the uncertainty calculations for the radiocarbon age of the Vinland Map (Donahue et al. 2002). First, the authors state that the 14C measurements of samples with chemical treatments B, C, D, and E “… result in consistent radiocarbon ages”, and that “… two (of these analyses) are 1.5 sigma, and the others are one sigma or less, from the weighted average.” In fact, the overall scatter of the data show that it is improbable that these data are statistically coherent, largely because analysis J21C lies 2.1 sigma from the weighted mean.

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Integrated process of determining the level of energy consumption of workers in the workplace

Russian Journal of Occupational Health and Industrial Ecology ◽

10.31089/1026-9428-2020-60-2-123-127 ◽

2020 ◽

pp. 123-127

Author(s):

T. K. Losik ◽

I. V. Ivanov ◽

E. V. Zibarev ◽

A. V. Konyukhov

Keyword(s):

Energy Consumption ◽

Full Range ◽

Experimental Studies ◽

Weighted Average ◽

Average Heart Rate ◽

Men And Women ◽

Human Energy ◽

Different Types ◽

Goals And Objectives

The article presents scientifically based methods and techniques for determining the level of energy consumption, which are most appropriate and convenient for practical use in mass physiological and hygienic and experimental studies, depending on their goals and objectives.Determination of the amount of human energy consumption should be carried out by monitoring studies during the shift, followed by the calculation of the weighted average heart rate, considering the different types of work performed, technological breaks and downtime. It is necessary to take into account the full range of environmental factors and the work process that contribute to the physical and thermal stress of working men and women in accordance with their age and body weight.

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Development of Accelerated Life Test Method of Hydraulic Pump

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.326-328.1861 ◽

2006 ◽

Vol 326-328 ◽

pp. 1861-1864

Author(s):

Dong Soo Jung ◽

Hyoung Eui Kim ◽

Sung Hun Kim ◽

E Sok Kang

Keyword(s):

Duty Cycle ◽

Weighted Average ◽

Life Time ◽

Test Method ◽

Accelerated Life Test ◽

Hydraulic Pump ◽

Life Test ◽

Accelerated Life ◽

Equivalent Load

This paper proposes a new accelerated life test method of hydraulic pump used in vehicles, which have multiple alternating loads. For determination of life time of hydraulic pump for given field conditions with respect to duty cycle, the equivalent load and speed of this unit has to be determined. Equivalent load and speed can be calculated from the given duty cycle using the predominant theory for cumulative fatigue damage. Finally, we can perform accelerated life test on hydraulic pump by determination of test pressure and speed from calculated equivalent cumulative damage per working cycle and weighted average speed.

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Optimization of Time-Weighted Average Air Sampling by Solid-Phase Microextraction Fibers Using Finite Element Analysis Software

Molecules ◽

10.3390/molecules23112736 ◽

2018 ◽

Vol 23 (11) ◽

pp. 2736 ◽

Cited By ~ 4

Author(s):

Bulat Kenessov ◽

Jacek Koziel ◽

Nassiba Baimatova ◽

Olga Demyanenko ◽

Miras Derbissalin

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Solid Phase Microextraction ◽

Solid Phase ◽

Weighted Average ◽

Internal Diameter ◽

Analysis Software ◽

Element Analysis ◽

Time Weighted Average

Determination of time-weighted average (TWA) concentrations of volatile organic compounds (VOCs) in air using solid-phase microextraction (SPME) is advantageous over other sampling techniques, but is often characterized by insufficient accuracies, particularly at longer sampling times. Experimental investigation of this issue and disclosing the origin of the problem is problematic and often not practically feasible due to high uncertainties. This research is aimed at developing the model of the TWA extraction process and optimization of TWA air sampling by SPME using finite element analysis software (COMSOL Multiphysics, Burlington, MA, USA). It was established that sampling by porous SPME coatings with high affinity to analytes is affected by slow diffusion of analytes inside the coating, an increase of their concentrations in the air near the fiber tip due to equilibration, and eventual lower sampling rate. The increase of a fiber retraction depth (Z) resulted in better recoveries. Sampling of studied VOCs using 23 ga Carboxen/polydimethylsiloxane (Car/PDMS) assembly at maximum possible Z (40 mm) was proven to provide more accurate results. Alternative sampling configuration based on 78.5 × 0.75 mm internal diameter SPME liner was proven to provide similar accuracy at improved detection limits. Its modification with the decreased internal diameter from the sampling side should provide even better recoveries. The results obtained can be used to develop a more accurate analytical method for determination of TWA concentrations of VOCs in air using SPME. The developed model can be used to simulate sampling of other environments (process gases, water) by retracted SPME fibers.

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