scholarly journals The statistical impact of experimental result scatter of asphalt mixtures on their numerical modelling

2019 ◽  
Vol 262 ◽  
pp. 05014 ◽  
Author(s):  
Cezary Szydłowski ◽  
Jarosław Górski ◽  
Marcin Stienss ◽  
Łukasz Smakosz
Keyword(s):  
Numerical Models ◽  
Asphalt Mixture ◽  
Experimental Result ◽  
Model Parameters ◽  
Test Results ◽  
Mean Values ◽  
Estimated Parameters ◽  
The Mean ◽  
Parameter Values ◽  
Test Outcomes

The paper presents selected test results of asphalt mixture conducted in low temperatures. The obtained parameters are highly diverse. It concerns ultimate breaking loads, stiffness parameters related to Young's modulus but also the fracture course. Statistical analysis upon the results makes it possible to relevantly estimate the material-defining parameter values. Such a random approach leads to the mean values of breaking and fracture-triggering loads, dealing with their dispersion too. The estimated parameters allow to form appropriate numerical models of asphalt mixture specimens. This type of analysis supports the laboratory tests. The paper presents the authors' simplified model considering non-uniform material features. The results reflect the scatter of real laboratory test outcomes. In order to do so an algorithm to calibrate the numerical model parameters was created.

scholarly journals Altruistic Behavior and Inter-Personal Trust among Behavioral Sciences and Engineering Students

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Nasrina Siddiqi ◽  
Sneha Mishra ◽  
M. Shafiq
Keyword(s):  
Engineering Students ◽  
Behavioral Science ◽  
Sampling Technique ◽  
Altruistic Behavior ◽  
Science Students ◽  
Test Results ◽  
Behavioral Sciences ◽  
Mean Values ◽  
Personal Trust ◽  
The Mean

The purpose of the present investigation was to compare the levels of Inter-Personal Trust and Altruistic Behavior between Behavioral Sciences and Engineering students. Convenience sampling technique has been used to collect data from 100 college students studying in Jamia Millia Islamia University. Of these 100 students, 50 were from Behavioral Science stream (Sociology, Psychology, Political Science and Social Work) and the other 50 were engineering students. The two groups of students (Engineering and Behavioral Sciences students) were compared on the said variables namely, Inter-Personal Trust and Altruistic Behavior, using independent sample t-test. Results suggest that Students studying Behavioral Sciences and those studying engineering differ significantly in terms of Inter-Personal Trust and Altruistic behavior. Moreover, the mean values indicate that Behavioral science students tend to score higher on Altruism as well as Inter-Personal Trust as compared to engineering students.

scholarly journals Study of warm inflationary models and their parameter estimation from CMB

2020 ◽  
Vol 29 (08) ◽  
pp. 2050055
Author(s):  
Richa Arya ◽  
Raghavan Rangarajan
Keyword(s):  
Model Building ◽  
Numerical Code ◽  
Index Formula ◽  
Physical Parameters ◽  
Model Parameters ◽  
Microwave Background ◽  
Mean Values ◽  
Warm Inflation ◽  
Inflationary Phase ◽  
The Mean

Warm inflation is a natural and well-motivated description of cosmic inflation which accounts for the inflaton dissipation and radiation production during the inflationary phase, neglected in the standard cold description. It results in crucial differences in the imprints on the Cosmic Microwave Background (CMB) radiation from the standard cold description. In this study, we consider warm inflation models with [Formula: see text] and [Formula: see text] potentials and estimate their model parameters consistent with CMB using the CosmoMC numerical code. These models are characterized by the inflaton self coupling, [Formula: see text], and the dissipation parameter, [Formula: see text], due to the inflaton’s dissipation into the other fields. Therefore, information about these physical parameters is essential from the perspective of the model building. In our analysis, we also calculate the spectral index, [Formula: see text], and the tensor-to-scalar ratio, [Formula: see text], for the mean values of the parameters and show that for the weak dissipative regime, [Formula: see text], is within the sensitivity of the next generation CMB polarization experiments, which is an important observational test for these models.

Monitoring Hydraulic Fracture Volume using Borehole to Surface EM and Conductive Proppant

Geophysics ◽  
2020 ◽  
pp. 1-76
Author(s):  
G. Michael Hoversten ◽  
Christoph Schwarzbach
Keyword(s):  
Hydraulic Fracture ◽  
Random Parameter ◽  
Dipole Source ◽  
Electrically Conductive ◽  
Mean Values ◽  
Inverse Solutions ◽  
The Mean ◽  
Stage Properties ◽  
Parameter Values ◽  
True Values

Numerical modeling of a North American hydraulic fracture experiment is done to demonstrate the accuracy with which the volume containing proppant could be estimated when electrically conductive proppant is used. An electromagnetic (EM) acquisition system with surface electric and magnetic field receivers and a grounded electric dipole source is simulated. The source has one electrode on the surface and one down a steel-cased well lateral that is adjacent to the lateral being hydraulically fractured. The simulations are preformed using measured EM noise at the site during hydraulic fracturing. A 3D OcTree finite-difference code is used that allows very fine meshing around the steel casings and fractures that can expand rapidly to the boundaries keeping memory requirements within available resources. The steel well casings are modeled in the forward and inverse solutions. Possible scenarios for source-receiver configurations, proppant conductivity, number of perforations per frac stage, variations in the steel casing properties as well as geometric errors in the locations of receivers and placement of the well laterals are considered. Hydraulic fracture stages are modeled as 3D geobodies with variability in the direction perpendicular to the well. Frac stages are embedded in a layered background model built from logged resistivities. The inversion of the EM data is first done on the pre-frac data for the anisotropic layered background resistivities, steel casing electrical conductivity and magnetic susceptibility. Next, data-differencing between the frac stage and the background or between successive frac stages is used for inversion of frac stage properties. A parametric box model is fit to each stage to estimate volume, length, height and mean stage conductivity. Hundreds of inversions starting from random parameter values are done to calculate parameter mean and standard deviations. The mean values of volume, length, and height are all within 20% of the true values.

scholarly journals Thoracoabdominal mobility evaluation by photogrammetry in newborns after expiratory flow increase technique

2017 ◽  
Vol 30 (4) ◽  
pp. 789-795 ◽  
Author(s):  
Júlia Isabel de Araújo Guerra ◽  
Danilo Alves Pinto Nagem ◽  
Cristiane Aparecida Moran ◽  
Valéria Lidyanne Souza Gomes ◽  
Juliana Macedo Campelo de Carvalho ◽  
...  
Keyword(s):  
Statistical Difference ◽  
Flow Direction ◽  
Test Results ◽  
Upper Airways ◽  
Mean Values ◽  
Hands On ◽  
Before And After ◽  
The Mean ◽  
Expiratory Flow ◽  
Paired T Test

Abstract Introduction: Expiratory flow increase is a maneuver of respiratory physical therapy that promotes flow direction to the upper airways however, when applied in newborns, it may result in changes of thoracoabdominal mobility. Objective: To evaluate the thoracoabdominal mobility by photogrammetry in newborns after expiratory flow increase technique. Methods: Experimental blind study performed with newborns in supine position on a support table with upper limbs flexed, abducted and externally rotated and hip flexed at 110°. Adhesive markers were allocated for geometric delimitation of the thoracoabdominal compartment and expiratory flow increase technique was performed for 5 minutes with the therapist’s hands on the thorax and abdomen. Newborns were filmed before and after the maneuver and the frames were analyzed in AutoCAD® software by a blinded investigator at the time of the procedure. The largest and the smallest thoracoabdominal area were expressed in cm2 and the mean values were compared between two moments (pre and post maneuver) by paired t test. Results: Twenty newborns with a mean age of 39 weeks were included. Before the maneuver, thoracoabdominal area was 56.1 cm2 during expiration and 59.7 cm2 during inspiration, and after the maneuver the value was 56.2 cm2 during expiration and 59.8 cm2 during inspiration, with no statistical difference between before and after (p = 0.97, p = 0.92, respectively). Conclusion: Results demonstrate that expiratory flow increase technique does not seem to change thoracoabdominal mobility of healthy newborns.

Influence of Mix Proportions on Water Absorption of RCA Concretes

2016 ◽  
Vol 722 ◽  
pp. 187-194
Author(s):  
Roman Jaskulski ◽  
Paweł Las ◽  
Wojciech Kubissa
Keyword(s):  
Water Absorption ◽  
Probabilistic Models ◽  
Recycled Aggregate ◽  
Test Results ◽  
Mean Values ◽  
Concrete Mixtures ◽  
The Subject ◽  
The Mean ◽  
Best Fit ◽  
Good Agreement

The subject of the work is to develop probabilistic models defining the water absorption of concretes made ​​with the use of recycled aggregate (RCA). For the study 16 series of concrete mixtures were made with a 50 mass% share of recycled aggregate in the whole amount of coarse aggregate. The analysis of test results aimed at formulating a relationship between water absorption value and selected parameters of the composition of concretes. The objective was to find a model giving the best fit between calculated values and test results. Formulated models were then used in probabilistic modeling absorption using a Monte Carlo simulation. The results indicate a good agreement of the mean values of water absorption and possibility of good fitting of the standard deviation if an additional summand is introduced into the model.

scholarly journals Aplikace fuzzy teorie v diagnostice výkonnostních předpokladů v tenisu

2019 ◽  
Vol 12 (2) ◽  
pp. 109-120 ◽  
Author(s):  
Antonín Zderčík ◽  
Ondřej Hubáček ◽  
Jiří Zháněl
Keyword(s):  
Fuzzy Evaluation ◽  
Test Results ◽  
Sports Performance ◽  
Mean Values ◽  
Tennis Players ◽  
Fitness Level ◽  
Control Regulation ◽  
Insignificant Difference ◽  
Motor Tests ◽  
The Mean

An important factor in sports performance in tennis is the optimal fitness level of the athlete. Diagnosisof its level is often done in practice by motor tests or tested batteries, the results found are an importantstarting point for control, regulation and planning of training. To test the test results, test standardsbased on classical probability (discrete) approach are most frequently used. Recently, some sportingresearch has also made attempts to use a so-called fuzzy approach, based on the theory of fuzzylogic created by L. A. Zadeh. The aim of the study is to present the principles of evaluation of test resultsusing fuzzy approaches and to compare the results obtained using a classical discrete approach.Presentation of the two approaches of the evaluation is documented on the results of testing of sets ofCzech tennis players aged 13–14 (n = 211, height 170 ± 8.9 cm, weight 57.2 ± 9.2 kg) who participatedin regular testing of Czech tennis from 2000 to 2015 using the TENDIAG1 test battery. FuzzME softwarewas used to demonstrate data analysis using fuzzy access. The degree of fuzzy and probability accesswas both materially and statistically significant (r = 0.94). The assessment of the factual significanceof differences in the mean values of the results obtained by both approaches using Cohen’s d showeda small, factually insignificant difference (d = 0.36). However, it is clear that fuzzy evaluation providesa significant differentiation of individual players’ partial results. Especially in the results of playersmoving on the boundaries of rating categories, fuzzy access allows a more gentle and more preciseresolution of the level of the conditions.

scholarly journals Anthropogenetic variability in the groups of homo- and heterosexually oriented individuals

Genetika ◽  
2015 ◽  
Vol 47 (2) ◽  
pp. 765-776
Author(s):  
Suzana Cvjeticanin
Keyword(s):  
Genetic Variability ◽  
Population Genetic ◽  
Control Group ◽  
Population Genetic Study ◽  
Test Results ◽  
Mean Values ◽  
Significant Difference ◽  
The Mean ◽  
Distribution Type

This population-genetic study compares morphophysiological and genetic variability in a group of homosexually oriented individuals from Serbia (N=96) with control group of heterosexual individuals (N=96) using a test of determination of homozygously recessive characteristics in humans (HRC-test). Results of our study revealed a statistically significant difference in the mean values of genetic homozygosity (control group 5.0+0.2 ; homosexuals 3.4 +0.1 HRCs, out of 20 observed characteristics) the differences in the distribution type, as well as in the variances of presence of specific combinations of such traits. These results suggest a complex polygenic difference between two observed systems. There is no difference in the degree of genetic homozygosity between the genders in each tested group of individuals. However, both homosexually oriented females and males have significantly lower mean values of HRCs compared to female and male heterosexuals.

Peritoneal physicochemical transport mechanisms: Hypotheses, models and controversies

2021 ◽  
pp. 089686082110024
Author(s):  
Matthew B Wolf
Keyword(s):  
Lymph Flow ◽  
Time Varying ◽  
Transport Mechanisms ◽  
Mean Values ◽  
Intraperitoneal Pressure ◽  
Model Predictions ◽  
Time Varying Parameters ◽  
Transport Kinetic ◽  
The Mean ◽  
Parameter Values

This study answers criticisms by Waniewski et al. of the recent paper by Wolf on peritoneal transport kinetic models. Their criticisms centre on the accuracy of the data used for model fits, the hypothesis presented, which involves changes in glucose membrane parameters at high peritoneal glucose concentration and on the necessary techniques required to achieve accurate model parameter estimation. In response, this article shows that (1) the mean values previously captured from graphical depictions of Heimburger et al. are not different than those captured from the recent Waniewski et al. graphs, (2) a much simpler hypothesis is proposed, which centres on intraperitoneal pressure-induced lymph flow during the dialysis dwell and (3) the finding that the new model predictions, with only two constant parameter values, as estimated by the Powell algorithm, give a closer fit than the Waniewski model, which uses many time-varying parameters. The current findings again bring into question of the validity of their vasodilation hypothesis, leading to transient changes in capillary surface area during the dwell.

Determining Temperature Dependencies of Sand Mould Thermal Properties

2014 ◽  
Vol 790-791 ◽  
pp. 452-457 ◽  
Author(s):  
Paweł K. Krajewski ◽  
Grzegorz Piwowarski ◽  
Witold K. Krajewski
Keyword(s):  
Physical Properties ◽  
Numerical Models ◽  
Mass Density ◽  
Measuring Method ◽  
Casting Method ◽  
Mean Values ◽  
The Mean ◽  
Sand Mould ◽  
Thermo Physical Properties ◽  
Good Agreement

The presented work is aimed at determining thermal diffusivity, thermal conductivity and heat capacity coefficients of silica quartz bentonite foundry sand. The values of the above thermo-physical properties were determined for temperature range of about 30 - 450 °C using theCasting measuring method[1-.The results obtained during the examinations presented in the paper can be useful when formulating boundary conditions in numerical models of heat and mass transfer in the system: casting mould ambient. TheCasting methodallows preserving real conditions during the experiment, i.e. contact of the mass with liquid metal and solidifying casting, and the obtained results are in a good agreement with the mean values available in literature. From the obtained results it follows that examinations should be also focused onthermo-physical properties vs. mass densitydependency.

Probabilistic Modeling of Dynamic Modulus Master Curves for Hot-Mix Asphalt Mixtures

2015 ◽  
Vol 2507 (1) ◽  
pp. 90-99 ◽  
Author(s):  
Noura Sirine Kahil ◽  
Shadi S. Najjar ◽  
Ghassan Chehab
Keyword(s):  
Probability Distribution ◽  
Coefficient Of Variation ◽  
Dynamic Modulus ◽  
Prediction Models ◽  
Shift Factor ◽  
Primary Objective ◽  
Model Parameters ◽  
Mean Values ◽  
Reduced Frequency ◽  
The Mean

Since the introduction of the dynamic modulus E* concept in the recent Mechanistic–Empirical Pavement Design Guide, there has been considerable interest in establishing reliable prediction models for E*. An investigation of the effectiveness of commonly used predictive models shows that E* predictions exhibit significant scatter around the measured values, with percentage of errors reaching about 6200%. A need exists for characterizing the uncertainties that are inherent in E* to serve as input to any future robust reliability analysis that aims at properly determining the probability of unsatisfactory performance of asphalt pavement systems. The primary objective of this study was to present a probabilistic model that would allow the user to determine a priori probability distribution for E* given knowledge about temperature and frequency. The seven-parameter model was based on the sigmoidal function and the shift factor that related reduced frequency to real frequency and temperature. The model was calibrated on the basis of a well-known published database that included 7,400 laboratory measurements of E* for 346 asphalt mixes. Monte Carlo simulations were used to propagate the uncertainties in the seven model parameters and determine realistic estimates of the mean, coefficient of variation, and probability distribution of E* at different frequencies and temperatures. Results showed that E* could be modeled by using a lognormal distribution with a mean that was estimated from the mean values of the parameters and a coefficient of variation that varied from a minimum of 0.55 for high values of reduced frequency to a maximum of 1.55 for lower values of reduced frequency.

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