Fuzzy-based approach for determination of characteristic values of measured geotechnical parameters

2000 ◽  
Vol 37 (5) ◽  
pp. 1131-1140 ◽  
Author(s):  
N O Nawari ◽  
R Liang
Keyword(s):  
Fuzzy Variable ◽  
Fuzzy Model ◽  
Mean Value ◽  
Geotechnical Properties ◽  
Distribution Functions ◽  
Safety Level ◽  
Geotechnical Parameters ◽  
Fuzzy Variables ◽  
Characteristic Values

Determination of the nominal (characteristic) values of geotechnical properties plays a crucial role within the limits states design (LSD or LRFD) concepts. The interrelationship between the process of the selection of the nominal value and the safety level is not clearly addressed in most of the new limits states design codes of practice for geotechnical engineering. Estimation of the characteristic values (p% fractile or the mean value) using the stochastic models is often linked up with some assumptions regarding the probability distribution functions. Probability theory has been perceived as a unique methodology to handle uncertainty in these geotechnical parameters despite the fact that some of the uncertainties associated with these geotechnical properties may be nonstochastic in nature. In this paper, the uncertainty connected with measured geotechnical properties is modeled using the fuzzy-reliability techniques. The measured parameters are rendered into fuzzy variables and the nominal values are characterized by fuzziness. The procedure presented is proposed as an alternative or complementary method to the estimate of the nominal values of geomaterials. The approach is illustrated with computational algorithms and a numerical example.Key words: characteristic value, nominal value, fuzzy model, fuzzy variable, resistance factor, probability.

An Inverse Analysis Method for Design Optimization With Both Statistical and Fuzzy Uncertainties

2006 ◽  
Author(s):  
Liu Du ◽  
Kyung K. Choi
Keyword(s):  
Design Optimization ◽  
Inverse Analysis ◽  
Random Variables ◽  
Mean Value ◽  
Performance Measure ◽  
Distribution Functions ◽  
Analysis Method ◽  
Fuzzy Variables ◽  
Analysis And Design ◽  
Inverse Analysis Method

Structural analysis and design optimization have recently been extended to consider various uncertainties. If the statistical data for the uncertainties are sufficient to construct the input distribution function, the uncertainties can be treated as random variables and RBDO is used; otherwise, the uncertainties can be treated as fuzzy variables and PBDO is used. However, many structural design problems include both uncertainties with sufficient data and uncertainties with insufficient data. For these problems, RBDO will yield an unreliable design since the distribution functions of uncertainties are not believable. On the other hand, treating the random variables as fuzzy variables and invoking PBDO may yield too conservative design with a higher optimum cost. This paper proposes a new design formulation using the performance measure approach (PMA). For the inverse analysis, this paper proposes a new most probable/possible point (MPPP) search method called maximal failure search (MFS), which is an integration of the enhanced hybrid mean value method (HMV+) and maximal possibility search (MPS) method. Some mathematical and physical examples are used to demonstrate the proposed inverse analysis method and design formulation.

The First Moments and Semi-Moments of Fuzzy Variables Based on an Optimism-Pessimism Measure with Application for Portfolio Selection

2020 ◽  
Vol 16 (02) ◽  
pp. 271-290
Author(s):  
Justin Dzuche ◽  
Christian Deffo Tassak ◽  
Jules Sadefo Kamdem ◽  
Louis Aimé Fono
Keyword(s):  
Linear Combination ◽  
Portfolio Selection ◽  
Fuzzy Variable ◽  
Expected Value ◽  
Mathematical Science ◽  
Optimal Portfolios ◽  
Fuzzy Variables ◽  
Convex Linear Combination

Possibility, necessity and credibility measures are used in the literature in order to deal with imprecision. Recently, Yang and Iwamura [L. Yang and K. Iwamura, Applied Mathematical Science 2(46) (2008) 2271–2288] introduced a new measure as convex linear combination of possibility and necessity measures and they determined some of its axioms. In this paper, we introduce characteristics (parameters) of a fuzzy variable based on that measure, namely, expected value, variance, semi-variance, skewness, kurtosis and semi-kurtosis. We determine some properties of these characteristics and we compute them for trapezoidal and triangular fuzzy variables. We display their application for the determination of optimal portfolios when assets returns are described by triangular or trapezoidal fuzzy variables.

scholarly journals BAYANAL code in geotechnical design based on Eurocode 7

2013 ◽  
Vol 45 (1) ◽  
pp. 17-26
Author(s):  
Simon Rabarijoely ◽  
Stanisław Jabłonowski ◽  
Kazimierz Garbulewski
Keyword(s):  
Numerical Code ◽  
Characteristic Parameters ◽  
Geotechnical Parameters ◽  
Promising Tool ◽  
Eurocode 7 ◽  
Geotechnical Design ◽  
Characteristic Values ◽  
High Degree ◽  
Geotechnical Characteristic

Abstract BAYANAL code in geotechnical design based on Eurocode 7. Geotechnical problems that are characterized by a high degree of complexity and uncertainty with respect to the input data are solved recently, using the Bayesian analysis (for instance the problem of a cautious estimation of the geotechnical characteristic parameters according to the Eurocode 7 requirements). The applicability of the Bayesian approach to geotechnics via a simple examples related to determination of characteristic values of geotechnical parameters for design structures is in the paper addressed. In order to select the characteristic parameters for the geotechnical design a new numerical code called BAYANAL was developed. Example of applying the BAYANAL code to analyse the DMT tests demonstrates that it is a powerful and promising tool in evaluation of ground properties and geotechnical parameters.

scholarly journals STABILIZATION AND SPECIFICATION OF CHARACTERISTIC VALUE OF GEOTECHNICAL PARAMETERS

2017 ◽  
Vol 10 ◽  
pp. 61
Author(s):  
Ivan Vaníček
Keyword(s):  
Laboratory Tests ◽  
Soil Stabilization ◽  
Logical Scheme ◽  
Geotechnical Parameters ◽  
Geotechnical Data ◽  
Earth Structures ◽  
Geotechnical Design ◽  
Characteristic Values ◽  
Different Soils

Soil stabilization, process, by which the soil properties are improved, is getting growing attention during last periods. Paper is focused on application for earth structures. Methods of soil stabilization together with their applicability for different soils are discussed firstly. The sensitivity of the process of the cautious estimation of the characteristic values of geotechnical parameters which are subsequently used for the design, is shown on the base of the logical scheme of the geotechnical design report for earth structures. Finally the need of the laboratory tests for the closer specification of the soil stabilization technology and also for the determination of the geotechnical data are discussed.

scholarly journals Evaluation of the mechanical properties of fluvial coarsegrained soils from dynamic penetration test

2021 ◽  
Vol 1209 (1) ◽  
pp. 012081
Author(s):  
E Kučová ◽  
M Kuvik
Keyword(s):  
Coarse Grained ◽  
Rock Properties ◽  
Penetration Test ◽  
Large Space ◽  
Geotechnical Parameters ◽  
Geotechnical Structures ◽  
Dynamic Penetration ◽  
Statistical Determination ◽  
Characteristic Values

Abstract Soil and rock properties are essential inputs for the design of geotechnical structures. But unlike man-made materials, the determination of the characteristic value is not simple, mostly because of the large space variability of the soils and rocks. In many cases, the large spatial variability makes it difficult to collect sufficient ground samples for further laboratory testing so that many tests are performed directly in the field. In Slovakia, the dynamic penetration test (DP) is, among others, a quite popular field test for soil investigation. From the measured data, it is possible to derive relative density (ID) shear (φ ef) and deformation (E def) parameters of coarse-grained soils. There are many available correlations between the DP results and geotechnical parameters. Therefore, it is necessary to choose the most appropriate one as it considerably affects the final evaluation. This paper shows the assessment of geotechnical parameters of coarse-grained fluvial soil from the DP results and presents the statistical determination of its characteristic values, which are furthermore compared with the nominal values used in Slovakia.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

Determination of Plasminogen in Clots and Thrombi

1966 ◽  
Vol 16 (01/02) ◽  
pp. 038-050 ◽  
Author(s):  
Ulla Hedner ◽  
Inga Marie Nilsson ◽  
B Robertson
Keyword(s):  
Mean Value ◽  
Main Mechanism ◽  
Clot Lysis ◽  
Post Mortem ◽  
Digestion Time ◽  
Normal Volunteers ◽  
Casein Solution ◽  
The Mean

SummaryThe plasminogen content was determined by a casein method in plasma and serum from 20 normal volunteers. The mean plasminogen content was found to be 10.1 ACU (the arbitrary caseinolytic unit defined in such a way that using a 3% casein solution and a digestion time of 20 min. at 37°C, 10 ACU gave an extinction of 0.300). No difference between serum and plasma regarding the plasminogen content was found.Plasminogen was determined in drained and drained plus washed clots prepared from 2 ml plasma. The highest values found in the drained clots were 0.9 ACU/clot and 0.2 ACU/clot in the drained plus washed clots.Plasminogen was also determined in drained and drained plus washed clots prepared from plasma with added purified plasminogen. The plasminogen was recovered in the washing fluid. According to these tests, then, purified added plasminogen is washed out of the clots.The plasminogen content of 20 thrombi obtained post mortem was also determined. The mean value was found to be 0.7 ACU/cm thrombus. Judging from our results, the “intrinsic clot lysis theory” is not the main mechanism of clot dissolution.

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.

The Natural Radioactivity in Food: A Comparison Between Different Feeding Regimes

2019 ◽  
Vol 15 (5) ◽  
pp. 493-499 ◽  
Author(s):  
Francesco Caridi ◽  
Santina Marguccio ◽  
Alberto Belvedere ◽  
Maurizio D`Agostino ◽  
Giovanna Belmusto
Keyword(s):  
Vegetable Oils ◽  
Natural Radioactivity ◽  
Specific Activity ◽  
Mean Value ◽  
Vegetable Food ◽  
Fish Samples ◽  
Feeding Regimes ◽  
Italian Origin ◽  
Dose Levels

Background: In this article a comprehensive study was carried out for the determination of natural radioactivity in animal and vegetable food (meat, fish, milk and derivates, legumes, cereals and derivates, fruit, hortalizas, vegetables, vegetable oils) typical of different feeding regimes, for the age category higher than 17 years. Methods: A total of eighty-five samples of Italian origin, coming from large retailers during the years 2014, 2015 and 2016, were analyzed through HPGe gamma spectrometry. Results: The specific activity of 40K was investigated and its mean value was found to be: (106.3 ± 6.9) Bq/kg for bovine, swine and sheep meat; (116.5 ± 9.7) Bq/kg for fish; (52.9 ± 3.1) Bq/kg for milk and derivates; (271.9 ± 16.7) Bq/kg for legumes; (67.2 ± 4.7) Bq/kg for cereals and derivates; (52.7 ± 4.4) Bq/kg for fruit; (72.9 ± 5.6) Bq/kg for hortalizas; (83.9 ± 6.5) Bq/kg for vegetables; lower than the minimum detectable activity for vegetable oils. For animal food the highest mean 40K activity concentration was found in fish samples; for vegetable food the highest one was detected in legumes. Conclusion: The evaluation of dose levels due to the food ingestion typical of Mediterranean, Vegetarian and Vegan diets was performed. The annual effective dose was found to be 0.16 mSv/y, 0.41 mSv/y and 0.54 mSv/y, respectively.

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