Statistical Analysis of the Properties of Advanced Fibers Designed for Titanium Alloy and Intermetallic Reinforcement

1992 ◽  
Vol 273 ◽  
Author(s):  
John R. Porter
Keyword(s):  
Weibull Modulus ◽  
Measured Data ◽  
Fiber Properties ◽  
Fiber Coating ◽  
Interfacial Sliding ◽  
Reinforcing Fibers ◽  
Sliding Resistance ◽  
Composite Properties ◽  
Thermochemical Stability

ABSTRACTThe mechanical properties of new ceramic reinforcing fibers need to be well characterized before their incorporation into composite materials. Critical fiber properties include strength and Weibull modulus, both off the spool and after matrix extraction, bundle strength, modulus and creep resistance. Important composite properties include thermochemical stability, interface debond energy and interfacial sliding resistance. Tailoring these interfacial properties invariably involves the use of a fiber coating that can, in turn, influence fiber properties. Methods of measuring strength related properties are addressed and the results of a computer simulation to assess the quality of measured data using statistical methods are presented. The simulation was developed to determine the errors associated with a strength/Weibull modulus determination based on a limited number of samples. Finally, an assessment of the effect of mixing of high and low quality fiber on bundle strength and composite properties is made.

scholarly journals Evaluation of mineral fiber properties using x-ray fluorescence analysis and measurement of natural radioactivity

2018 ◽  
Vol 170 ◽  
pp. 03018 ◽  
Author(s):  
Andrey Medvedev ◽  
Ekaterina Bobrova ◽  
Alexey Poserenin ◽  
Ervand Zarmanyan
Keyword(s):  
Fluorescence Analysis ◽  
Mineral Wool ◽  
Factors Affecting ◽  
Mineral Fibers ◽  
X Ray ◽  
Fiber Properties ◽  
Building Systems ◽  
Heavy Metal Oxides

The article analyzes the factors affecting the longevity of insu-lating systems and the operational resistance of products based on mineral fibers. It is emphasized that the ratio of acid oxides contained in the charge to the main oxides is the main factor influencing the operational resistance of mineral fibers, as well as the energy intensity of their production. A hy-pothesis has been put forward and confirmed that the operational resistance of a fiber depends on the content of heavy metals (their oxides) in the ini-tial charge. Determination of the elemental composition of stone wool samples was carried out by X-ray fluorescence analysis. Conducted sam-ples with a different acidity module of the study, show, that the fibers are safe by radiation indices, and their operational resistance can be affected by heavy metal oxides. It is substantiated that the durability of building systems in which mineral wool products are used as thermal insulation is determined by the properties of mineral wool products, the literacy of de-sign solutions and the quality of installation. The properties of mineral wool products, including their operational resistance, depend on the prop-erties of mineral fibers and the observance of technological regimes both on the fact of the most complete curing of the binder and on the features of formation of the volume-oriented structure of the mineral wool carpet.

Numerical Investigation of Curing Process in Reaction Injection Molding of Rubber for Quality Improvements

2011 ◽  
Vol 462-463 ◽  
pp. 1206-1211 ◽  
Author(s):  
Seyyed Mohammad Javadi ◽  
Mohammad Moghiman ◽  
Mohammad Reza Erfanian ◽  
Naseh Hosseini
Keyword(s):  
Three Dimensional ◽  
Measured Data ◽  
Production Costs ◽  
Curing Process ◽  
Quality Improvements ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Final Temperature ◽  
Reaction Injection Molding

A large number of rubber products are formed into their final shape by vulcanization. In particular, curing process of rubber is the final step in manufacturing many rubber products and determines both the quality of the resulting product as well as production costs. This paper is devoted to the simulation of rubber curing process in a three-dimensional model. The effects of final temperature of mold are investigated on curing process and quality of final product. The results were compared with the experimentally measured data, which confirmed the accuracy and applicability of the method.

scholarly journals Organic versus integrated apple growing: II. differences in fruit quality parameters

2009 ◽  
Vol 15 (4) ◽  
Author(s):  
P. T. Nagy ◽  
Z. Szabó ◽  
J. Nyéki ◽  
I. Gonda ◽  
I. J. Holb
Keyword(s):  
Production System ◽  
Dry Matter ◽  
Quality Parameters ◽  
Measured Data ◽  
Matter Content ◽  
Research Station ◽  
Dry Matter Content ◽  
Nutrients Uptake ◽  
Good Agreement

The aim our study was to establish whether significant differences in nutrients uptake and quality of fruit existbetween organic and integrated grown apples. The study was performed at the orchard Fruit Research Station, University of Debrecen, at Debrecen-Pallag during 2002–2004. Diameter (mm), weight (g), firmness (N/cm2), dry matter (%) and Vitamin C in fruit were determined. Diameter data showed that the size of apples strongly depended on cultivars and organic apples were larger than integrated ones. Moreover, the effect of year and species strongly affected the apple diameter, size and weight. Measured data of firmness were good agreement in data of diameter and weight. Larger fruits have lower values of firmness due to the structure of fruit flesh. Dry matter content of apples varied between 14.66 and 18.07 in integrated, and 12.87 and 17.29 in organic apples according to cultivars. Values were affected by years and cultivars. From results it was evident that the dry matter content of apples affected by production system. It was lower in organic samples than integrated ones.Vitamin C content of apples was stronger affected by species and years than production system.

scholarly journals Evaluation of remotely sensed precipitation product in a hydrological model of the Bednja watershed

2021 ◽  
Vol 73 (04) ◽  
pp. 335-348
Keyword(s):  
Spatial Distribution ◽  
Spatial Analysis ◽  
Input Data ◽  
Hydrological Model ◽  
Remotely Sensed ◽  
Measured Data ◽  
Precipitation Product ◽  
Monthly Distribution ◽  
Runoff Model

In this paper, a statistical and spatial analysis of precipitation for the period 2000-2018 for the Bednja basin was performed, were the measured data from meteorological and/or rainfall stations of Croatian Meteorological and Hydrological Service (DHMZ) were compared with the data in form of remotely sensed precipitation product - CHIRPS (Climate Hazards Group InfraRed Precipitation with Station). The results of the analysis in the form of the annual sum, monthly distribution within the year and the spatial distribution and input data ratio over the basin show a good correlation between the measured and remotely sensed precipitation. In order to further evaluate the quality of the remotely sensed product, a SWAT hydrological runoff model was created.

scholarly journals Evaluation of vehicle parameters depending on technical vehicle inspection

Tehnika ◽  
2021 ◽  
Vol 76 (3) ◽  
pp. 352-357
Author(s):  
Vlastimir Dedović ◽  
Vojislav Božanić ◽  
Milan Božović
Keyword(s):  
Road Safety ◽  
Measurement Data ◽  
Measured Data ◽  
Safety System ◽  
Resistance Measurement ◽  
Safety Improvement ◽  
Vehicle Inspection ◽  
The Impact ◽  
Different Levels

In a strategic document of EU for Road safety improvement, up to 2030, "safe vehicle" is recognized as one of the pillars of a stable Road safety system. The part of the "safe vehicle" pillar is technical vehicle ispection, where parameters important for road safety are periodically checked. The aim of this work is to determine the quality of the measurement data and the ability to repeat measurements of some parameters during technical vehicle inspection, or more precisely, to determine whether measured data of turning wheel resistance and brakes ovality differ depending on the inspection place. The research is done by inspecting ten vehicles at five inspection places with different levels of resources use. The results show that the spread of measured data of turning wheel resistance is statistically significant and that it depends on the inspection place, as well as that measured data of turning wheels resistance significantly vary between inspection places. The measured percentage of brakes ovality is different from one inspection place to another, but the differences are statistically significant only for right wheels. The impact of inspection place, although less than in turning wheel resistance measurement, is still significant.

scholarly journals Study on the influence of the cotton storage process on the quality indicators of fiber and yarn

2021 ◽  
Vol 939 (1) ◽  
pp. 012053
Author(s):  
Q Jumaniyazov ◽  
M Ismatova ◽  
I Abbazov ◽  
D Kazakova
Keyword(s):  
Quality Indicators ◽  
Lower Layer ◽  
Average Length ◽  
Fiber Quality ◽  
Viscosity Index ◽  
Light Output ◽  
Fiber Properties ◽  
Yarn Properties ◽  
Output Coefficient

Abstract This article defines fiber quality indicators that differ in laboratory conditions from the upper, middle and lower layers of Bukhara-6 breeding varieties of cotton, in the modern system HVI 1000 SA. Based on the results of the study, histograms of changes in the quality of cotton fiber in the layers of the harem are presented. As an alternative, the quality indicators of yarn obtained in the laboratory spinning device “Sherli” of small size from fiber were determined. As can be seen from the analysis of the test results, it was found that the comparative elongation strength of cotton obtained from the lower layer of the stack, the upper average length, elongation at break, the light output coefficient, decreased compared to other layers of the stack, on the contrary, the index of hip fibers, increased, decreased compared to other layers of the stack. In addition, according to the results of the tests obtained, the fiber viscosity index was obtained – the correlation between the properties of fibers and the properties of yarn, the thread viscosity index was estimated by the CSP (COUNT STRENGTH PRODUKT) coefficient, which was determined by the formula for carded yarn obtained in the laboratory spinning device “Sherli” from fiber stored in the refrigerator. The obtained results showed that the relationship between fiber properties and yarn properties due to the fact that the maturity index of a thread is at the top of the stack compared to the middle and lower part of the stack.

scholarly journals Identification of a synchronous generator parameters using recursive least squares and Kalman filter

2021 ◽  
Vol 12 (1) ◽  
pp. 13-21
Author(s):  
Diego Alberto Bravo Montenegro ◽  
Carlos Felipe Rengifo ◽  
Cristian Giron ◽  
Jhon Palechor
Keyword(s):  
Kalman Filter ◽  
Least Squares ◽  
Synchronous Generator ◽  
Measured Data ◽  
Operating Conditions ◽  
Recursive Least Squares ◽  
Phase Voltage ◽  
Three Phase ◽  
Better Than

The comparison between recursive least squares (RLS) and Kalman filter (KF) is presented in this paper, both methods were adequate to estimate six parameters of a synchronous machine. The work focused on finding the operating conditions which the quality of the identification achieved with Kalman filter is better than recursive least squares. A linear model of the machine is used in order to considerate the currents and their derivatives as the system inputs while the three-phase voltage signals are the outputs. Furthermore two experiments with simulated and measured data were carried out, three operating scenarios and two variations of the algorithms respectively were considered. Despite the great similarity and good performance of both methods, it was found that Kalman filter slightly exceeded least squares due to the fact that it presented smaller oscillations in the estimated value of the parameters for any operating condition.

scholarly journals European UV DataBase (EUVDB) as a repository and quality analyser for solar spectral UV irradiance monitored in Sodankylä

2016 ◽  
Vol 5 (2) ◽  
pp. 333-345 ◽  
Author(s):  
Anu Heikkilä ◽  
Jussi Kaurola ◽  
Kaisa Lakkala ◽  
Juha Matti Karhu ◽  
Esko Kyrö ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Statistical Analysis ◽  
Quality Indicators ◽  
Uv Spectra ◽  
Measured Data ◽  
Uv Irradiance ◽  
Atmospheric Data ◽  
Solar Uv

Abstract. Databases gathering atmospheric data have great potential not only as data storages but also in serving as platforms for coherent quality assurance (QA). We report on the flagging system and QA tools designed for and implemented in the European UV DataBase (EUVDB; http://uv.fmi.fi/uvdb/) for measured data on solar spectral UV irradiance. We confine the study on the data measured by Brewer #037 MkII spectroradiometer in Sodankylä (67.37° N, 26.63° E) in 1990–2014. The quality indicators associated with the UV irradiance spectra uploaded into the database are retrieved from the database and subjected to a statistical analysis. The study demonstrates the performance of the QA tools of the EUVDB. In addition, it yields an overall view of the availability and quality of the solar UV spectra recorded in Sodankylä over a quarter of a century. Over 90 % of the four main quality indicators are flagged as GREEN, indicating the highest achievable quality. For the BLACK flags, denoting data not meeting the pre-defined requirements, the percentages for all the indicators remain below 0.12 %.

Fault Detection and Optimal Sensor Location in Vehicle Suspensions

2003 ◽  
Vol 9 (3-4) ◽  
pp. 337-359 ◽  
Author(s):  
P. Metallidis ◽  
G. Verros ◽  
S. Natsiavas ◽  
C. Papadimitriou
Keyword(s):  
System Identification ◽  
Fault Detection ◽  
Piecewise Linear ◽  
Parametric Identification ◽  
Measured Data ◽  
Model Parameters ◽  
Vehicle Suspensions ◽  
Simulated Test ◽  
Sensor Configuration

A statistical system identification methodology is applied for performing parametric identification and fault detection studies in nonlinear vehicle systems. The vehicle nonlinearities arise due to the function of the suspension dampers, which assume a different damping coefficient in tension than in compression. The suspension springs may also possess piecewise linear characteristics. These lead to models with parameter discontinuities. Emphasis is put on investigating issues of unidentifiability arising in the system identification of nonlinear systems and the importance of sensor configuration and excitation characteristics in the reliable estimation of the model parameters. A methodology is proposed for designing the optimal sensor configuration (number and location of sensors) so that the corresponding measured data are most informative about the condition of the vehicle. The effects of excitation characteristics on the quality of the measured data are systematically explored. The effectiveness of the system identification and the optimal sensor configuration design methodologies is confirmed using simulated test data from a classical two-degree-of-freedom quartercar model as well as from more involved and complete vehicle models, including four-wheel vehicles with flexible body.

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