Relevant bibliographies by topics / Distribution analysis method

Academic literature on the topic 'Distribution analysis method'

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Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Distribution analysis method"

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DEBBAL, S. M. "Heart Cardiac Sounds analysis using the Wigner distribution (WD) Method." Clinical Cardiology and Cardiovascular Interventions 04, no. 15 (September 20, 2021): 01–04. http://dx.doi.org/10.31579/2641-0419/216.

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This paper is concerned a “The Wigner distribution (WD)” analysis of the Heart cardiac (or phonocardiogram signals: PCG). The Wigner distribution (WD) and the corresponding WVD (Wigner Ville Distribution) have shown good performances in the analysis of non-stationary and quantitative measurements of the time-frequency PCG signal characteristics. It is shown that these transforms provides enough features of the PCG signals that will help clinics to obtain diagnosis.
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Li Wei, Li Wei, and Bing-Wu Fang Li Wei. "Safety Analysis Method of Mixed Failure Model using Temporal Bayesian Network." 網際網路技術學刊 23, no. 4 (July 2022): 727–34. http://dx.doi.org/10.53106/160792642022072304008.

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<p>Dynamic Fault Tree (DFT) is used widely in the community of reliability and safety analysis of a complex system. DFT is a high-level modeling language lacking formal semantics, so we need to convert it to a mathematical model to analyze. The conventional analysis method can only solve the DFT with discrete or exponential distribution, but not the DFT with mixed distributions. To this end, we first propose a TBN framework to represent the DFT with mixed failure distribution by extending the BN and introduce Dirac delta functions and unit-step functions into the framework to represent the logical relationship and temporal relationship between the nodes, respectively. To run the standard BN inference algorithm over TBN, we fit the failure distribution of the nodes by using k-piece and n-degree polynomials. We then propose a transformation method from DFT to TBN and prove the equivalence of the transformation. Finally, the analysis of the DFT model of the X2000 avionics system shows that our approach can effectively analyze the reliability of mixed distribution failure models. Moreover, the accuracy and efficiency of the analysis are significantly better than current mainstream methods.</p> <p>&nbsp;</p>
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LIU, S. G., P. WANG, and Z. G. LI. "NON-NORMAL STATISTICAL TOLERANCE ANALYSIS USING ANALYTICAL CONVOLUTION METHOD." Journal of Advanced Manufacturing Systems 07, no. 01 (June 2008): 127–30. http://dx.doi.org/10.1142/s0219686708001218.

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In statistical tolerance analysis, it is usually assumed that the statistical tolerance is normally distributed. But in practice, there are many non-normal distributions, such as uniform distribution, triangular distribution, etc. The simple way to analyze non-normal distributions is to approximately represent it with normal distribution, but the accuracy is low. Monte-Carlo simulation can analyze non-normal distributions with higher accuracy, but is time consuming. Convolution method is an accurate method to analyze statistical tolerance, but there are few reported works about it because of the difficulty. In this paper, analytical convolution is used to analyze non-normal distribution, and the probability density functions of closed loop component are obtained. Comparing with other methods, convolution method is accurate and faster.
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Guo, Li, Mingqing Liu, Ronghua Lu, Shensheng Han, and Jing Chen. "Analysis of above-threshold ionization by “Wigner-distribution-like function” method." Laser and Particle Beams 37, no. 4 (September 18, 2019): 448–62. http://dx.doi.org/10.1017/s0263034619000569.

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AbstractAbove-threshold ionization (ATI) is one of the most fundamental processess when atoms or molecules are subjected to intense laser fields. Analysis of ATI process in intense laser fields by a Wigner-distribution-like (WDL) function is reviewed in this paper. The WDL function is used to obtain various time-related distributions, such as time-energy distribution, ionization time distribution, and time-emission angle distribution and so on, of atoms in laser field pulses with different laser parameters. For the linearly polarized laser pulses, the time-energy distribution intuitively shows from a quantum point of view the relationship between the ionization moment and the final energy and clearly reveals the origin of interference structures in the photoelectron spectrum. In particular, for linearly polarized few-cycle laser pulses, all calculated distributions show the dependence of electron behavior on the ionization time, emission direction, and carrier-envelope phase (CEP). For elliptically polarized few-cycle pulses, we calculate the angular distribution, ionization time distribution, and time-emission distribution, which are compared with the semiclassical calculations. Analysis shows that the offset angle (difference between positions of the peaks in the angular distributions obtained by two methods) in the angular distributions does not correspond to the offset time (difference between positions of the peaks in the ionization time distributions obtained by two methods) in the ionization time distributions, which implies that the attosecond angular streaking technique based on this correspondence between the offset angle and time is in principle inaccurate. Furthermore, the offset time cannot be interpreted as tunneling time.
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Zhang, Peng, Qian Yu, Yuexian Hou, Dawei Song, Jingfei Li, and Bin Hu. "Generalized Analysis of a Distribution Separation Method." Entropy 18, no. 4 (April 13, 2016): 105. http://dx.doi.org/10.3390/e18040105.

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Zhang, YL, and YM Zhang. "A new stochastic analysis method for mechanical components." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 227, no. 8 (November 23, 2012): 1818–29. http://dx.doi.org/10.1177/0954406212467735.

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Univariate dimension-reduction integration, maximum entropy principle, and finite element method are employed to present a computational procedure for estimating probability densities and distributions of stochastic responses of structures. The proposed procedure can be described as follows: 1. Choose input variables and corresponding distributions. 2. Calculate the integration points and perform finite element analysis. 3. Calculate the first four moments of structural responses by univariate dimension-reduction integration. 4. Estimate probability density function and cumulative distribution function of responses by maximum entropy principle. Numerical integration formulas are obtained for non-normal distributions. The non-normal input variables need not to be transformed into equivalent normal ones. Three numerical examples involving explicit performance functions and solid mechanic problems without explicit performance functions are used to illustrate the proposed procedure. Accuracy and efficiency of the proposed procedure are demonstrated by comparisons of the estimated probability density functions and cumulative distribution functions obtained by maximum entropy principle and Monte Carlo simulation.
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Simanavičienė, Rūta, and Vaida Petraitytė. "Sensitivity Analysis of the TOPSIS Method in Respect of Initial Data Distributions." Lietuvos statistikos darbai 55, no. 1 (December 20, 2016): 45–51. http://dx.doi.org/10.15388/ljs.2016.13866.

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The present article investigates the sensitivity of the multiple criteria decision-making method TOPSIS in respectof attribute probability distributions. To carry out research, initial data – attribute values – were generated according to anormal, log-normal, uniform, and beta distributions. Decision matrixes were constructed from the generated data. Byapplying the TOPSIS method to the matrixes generated, result samples were received. A statistical analysis was conductedfor the results obtained, which revealed that the distributions of the initial data comply with the distributions of the resultsreceived by the TOPSIS method. According to the most common alternative rank value, it was ascertained that the TOPSISmethod is the most sensitive for data distribution according to beta distribution, and the least sensitive for data distributionaccording to lognormal distribution.
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Cespedes, R. G. "New method for the analysis of distribution networks." IEEE Transactions on Power Delivery 5, no. 1 (1990): 391–96. http://dx.doi.org/10.1109/61.107303.

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Spiliotis, M., and G. Tsakiris. "Water Distribution System Analysis: Newton-Raphson Method Revisited." Journal of Hydraulic Engineering 137, no. 8 (August 2011): 852–55. http://dx.doi.org/10.1061/(asce)hy.1943-7900.0000364.

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Matsuo, Munetsugu, Koichi Kawasaki, and Tetsuya Sugai. "A New Method for Orientation Distribution Function Analysis." Advances in X-ray Analysis 29 (1985): 443–49. http://dx.doi.org/10.1154/s0376030800010569.

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AbstractAs a means for quantitative texture analysis, the crystallite orientation distribution function analysis has an important drawback: to bring ghosts as a consequence of the presence of a non-trivial kernel which consists of the spherical harmonics of odd order terms. In the spherical hamonic analysis, ghosts occur in the particular orientations by symmetry operation from the real orientation in accordance with the symmetry of the harmonics of even orders. For recovery of the odd order harmonics, the 9th-order generalized spherical harmonics are linearly combined and added to the orientation distribution function reconstructed from pole figures to a composite function. The coefficients of the linear combination are optimized to minimize the sum of negative values in the composite function. Reproducibility was simulated by using artificial pole figures of single or multiple component textures. Elimination of the ghosts is accompanied by increase in the height of real peak in the composite function of a single preferred orientation. Relative fractions of both major and minor textural components are reproduced with satisfactory fidelity In the simulation for analysis of multi-component textures.
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Dissertations / Theses on the topic "Distribution analysis method"

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Kasolis, Fotios. "The Material Distribution Method : Analysis and Acoustics applications." Doctoral thesis, Umeå universitet, Institutionen för datavetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-92538.

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For the purpose of numerically simulating continuum mechanical structures, different types of material may be represented by the extreme values {,1}, where 0<1, of a varying coefficient  in the governing equations. The paramter  is not allowed to vanish in order for the equations to be solvable, which means that the exact conditions are approximated. For example, for linear elasticity problems, presence of material is represented by the value  = 1, while  =  provides an approximation of void, meaning that material-free regions are approximated with a weak material. For acoustics applications, the value  = 1 corresponds to air and  =  to an approximation of sound-hard material using a dense fluid. Here we analyze the convergence properties of such material approximations as !0, and we employ this type of approximations to perform design optimization. In Paper I, we carry out boundary shape optimization of an acoustic horn. We suggest a shape parameterization based on a local, discrete curvature combined with a fixed mesh that does not conform to the generated shapes. The values of the coefficient , which enters in the governing equation, are obtained by projecting the generated shapes onto the underlying computational mesh. The optimized horns are smooth and exhibit good transmission properties. Due to the choice of parameterization, the smoothness of the designs is achieved without imposing severe restrictions on the design variables. In Paper II, we analyze the convergence properties of a linear elasticity problem in which void is approximated by a weak material. We show that the error introduced by the weak material approximation, after a finite element discretization, is bounded by terms that scale as  and 1/2hs, where h is the mesh size and s depends on the order of the finite element basis functions. In addition, we show that the condition number of the system matrix scales inversely proportional to , and we also construct a left preconditioner that yields a system matrix with a condition number independent of . In Paper III, we observe that the standard sound-hard material approximation with  =  gives rise to ill-conditioned system matrices at certain wavenumbers due to resonances within the approximated sound-hard material. To cure this defect, we propose a stabilization scheme that makes the condition number of the system matrix independent of the wavenumber. In addition, we demonstrate that the stabilized formulation performs well in the context of design optimization of an acoustic waveguide transmission device. In Paper IV, we analyze the convergence properties of a wave propagation problem in which sound-hard material is approximated by a dense fluid. To avoid the occurrence of internal resonances, we generalize the stabilization scheme presented in Paper III. We show that the error between the solution obtained using the stabilized soundhard material approximation and the solution to the problem with exactly modeled sound-hard material is bounded proportionally to .
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Karadag, Rukiye. "Temperature Distribution In Power Transformers." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615162/index.pdf.

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As in all other electrical equipments it is essential to estimate the temperature distribution in transformer components in the design stage and during the operation since temperatures above thermal limits of these components might seriously damage them. Thermal models are used to predict this vital information prior to actual operations. In this study, a three dimensional model based on the Finite Element Method (FEM) is proposed to estimate the temperature distribution in the three phase, SF6 gas insulated-cooled power transformer. This model can predict the temperature distribution at the specific discredited locations in the transformer successfully.
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Erturk, Mehmet. "Efficiency Analysis Of Turkish Natural Gas Distribution Companies By Using Dea Method." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610796/index.pdf.

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The history of natural gas in Turkey started in 1970s by the usage of domestic gas in cement factories. However, natural gas began penetrating the energy market in 1980s with the usage of natural gas in Ankara. In the following years, the number of cities using natural gas reached six. Then, a new era started with the enactment of Natural Gas Market Law in 2001 and 53 distribution tenders have been realized by Energy Market Regulatory Authority until 2009. This thesis analyzes the performance of 38 Turkish natural gas distribution companies by using a non-parametric method, Data Envelopment Analysis. The results are used to determine the most proper model specification, to detect the important criteria affecting the efficiency levels and to find the common characteristics of the most inefficient firms. The results show that public firms compared to private firms, non-tender firms compared to tender firms, large firms compared to small firms and firms operating in more developed areas compared to firms operating in underdeveloped areas utilize resources and manage costs more efficiently. However, we can not get a certain conclusion about the comparison of old firms and new firms. Lastly, we try to detect the common characteristics of the most inefficient firms and find that the major problem is low delivery amount.
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Bahai, Hamid R. S. "A hybrid method for load, stress and fatigue analysis of drill string screw connectors." Thesis, Queen Mary, University of London, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284406.

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Mooney, Jayne. "The prevalence and social distribution of domestic violence : an analysis of theory and method." Thesis, Middlesex University, 1994. http://eprints.mdx.ac.uk/6383/.

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Domestic violence is recognised as an area that requires more detailed research, particularly on the general population. Indeed the lack of authoritative statistics on the extent of domestic violence is considered to restrict the development of preventative or remedial action to alleviate the problem. This thesis is concerned, therefore, with the development of a methodology in order to generate data on the incidence and prevalence of domestic violence, the relationship of this to current theory and the implications for policy. The main research component involved a victimisation survey adapted to deal with the specific problems of researching domestic violence. It utilized sensitive interviewing techniques, carefully worded questionnaires, a self-complete questionnaire (the 'piggy-back' method) and vignettes detailing 'conflict' situations which could lead to violence. 571 women and 429 men were interviewed which makes it the largest survey on domestic violence to be conducted in Great Britain. A qualitative component was additionally incorporated into the methodology in order to fully explore the experience of domestic violence. The primary focus of the research was on women's experiences of violence from husbands and boyfriends, including ex-partners, although additional information was collected on other forms domestic of and non-domestic violence against both men and women. The project investigated the extent of domestic violence; its variation by subgroup; the nature, context and impact of the violence; definitions; levels and patterns of reporting to the various agencies and satisfaction with the response; the relationship of domestic to stranger violence; the location of domestic violence and non-domestic violence and the gendered distribution of violence. The examination of so many areas could not have been achieved without the use of a multiplicity of methods. This thesis, however, deals not only with the development of methodology and the subsequent findings arising from the research project. It also analyses four major criminological theories (classicism, including the new administrative criminology; positivism; feminism and left realism) in relation to domestic violence. It delineates the main principles of each theory, details how it attempts to explain, research and tackle domestic violence and identifies both strengths and weaknesses. Furthermore, the empirical data generated by the research project enables the testing of hypotheses derived from the theoretical literature about the nature of violence, particularly with respect to its social and spatial patterning. On examination, the approaches of radical feminism and left realism are singled out as having the greatest purchase on the Phenomenon and a synthesis of these positions is demarcated: a feminist realism within criminology. Finally, both the research findings and theoretical discussion inform the policy recommendations. Both long-term and short-term initiatives are considered and an emphasis is placed on development of policy that is both multiagency and woman-centred.
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ALI, MOLLA MOHAMMAD. "A PROBABILISTIC ANALYSIS OF THE DISTRIBUTION OF COLLAPSING SOIL IN TUCSON USING KRIGING METHOD." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184180.

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An analytical investigation was carried to determine the nature and extent of the variability of selected collapse criteria and collapse-related soil parameters both areally and with depth within the city of Tucson. Collapse-related soil parameters of about 1000 sample points from over 400 borehole locations throughout the Tucson basin were collected from several consulting geotecnical engineering offices of the city. Statistical analysis on seven data sets corresponding to six different depth increments below the surface showed high dispersion tendencies expressed by the value of coeffecient of variation (cov). The value of cov was found to increase linearly with depth for most criteria and parameters. All the collapse criteria and collapse-related soil parameters were found to follow the Gamma distribution function except insitu dry density bd) and porosity (n₀) which were found to follow the Weibull distribution function. A polynomial regression model developed for the collapse parameter Cp showed that it varies with depth almost linearly. A stepwise regression analysis revealed that the collapse parameter Cp is strongly correlated with γd and insitu moisture content, woo Factor analysis validates this finding by producing two strong factors γd and insitu degree of saturation, s₀ which described almost 80% of the variation encountered in the data. The application of geostatistical concepts was found to be feasible in analyzing the collapse criteria and collapse-related soil parameters. Almost all criteria and parameters were strongly dependent spatially. A spherical variogram model was found to be appropriate for them. The method of Ordinary Kriging provided an unbiased estimation of a parameter at an unsampled location with known estimation variance. The method of Indicator Kriging was used to develop contour plots for the various data sets that showed the probability that the value of a certain parameter is above or below a critical level. These contour plots can be used to identify the areas within the City of Tucson that contain soils having a low- medium- or high-collapse potential. The ability to predict the occurence of such soils with a known degree of certitude is invaluable to planners, developers and geotechnical engineers.
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Li, Ji. "Cox Model Analysis with the Dependently Left Truncated Data." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/math_theses/88.

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A truncated sample consists of realizations of a pair of random variables (L, T) subject to the constraint that L ≤T. The major study interest with a truncated sample is to find the marginal distributions of L and T. Many studies have been done with the assumption that L and T are independent. We introduce a new way to specify a Cox model for a truncated sample, assuming that the truncation time is a predictor of T, and this causes the dependence between L and T. We develop an algorithm to obtain the adjusted risk sets and use the Kaplan-Meier estimator to estimate the Marginal distribution of L. We further extend our method to more practical situation, in which the Cox model includes other covariates associated with T. Simulation studies have been conducted to investigate the performances of the Cox model and the new estimators.
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Tafesse, Solomon. "Physical characterization of coarse clasts with 3D image-analysis method : development, evaluation and application." Doctoral thesis, KTH, Teknisk geologi och geofysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-101388.

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This thesis presents a novel three dimensional (3D) image-analysis method for characterizing the physical characteristics of coarse particles in the field, and introduces new methodology for the total analysis of glacial till samples. The novel image analysis method, called the GID method, is capable of determining the size, shape and surface texture of each individual clast analysed. Images of particles are taken in the field and analysis is done in the laboratory. Therefore the GID method makes it feasible to analyse statistically representative large sample in short period; for poorly sorted sediments, such as till, one-tonne is required if the analysis includes cobble size. The capability of the GID method was demonstrated by studying coarse clasts (20-200 mm) from till. There is excellent agreement in the results of the size distribution obtained from the GID method and sieve analysis. The GID method results for size and shape parameters show high and very high repeatability. The particle angularity in the GID method has not been measured to acceptable level; the repeatability test shows some variability. The new methodology for total analysis of till applied the GID method at four different locations in Sweden. The total analysis included 3D size and shape distribution of coarse particles coupled to electrical resistivity, lithological distribution and magnetic susceptibility of the clasts. The results show clear difference in the till samples from the different sites.

QC 20120828

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Ngunkeng, Grace. "Statistical Analysis of Skew Normal Distribution and its Applications." Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1370958073.

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Jia, Xiaoyuan. "The Application of Linear Superposition Method on Water Distribution Systems Analysis of Contaminant Intrusion Events." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1337889123.

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Books on the topic "Distribution analysis method"

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Brown, Andrew M. Development of a probabilistic component mode synthesis method for the analysis of non-deterministic substructures. Washington, DC: [National Aeronautics and Space Administration, 1995.

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Torres, Rodolfo H. Boundedness results for operators with singular kernels on distribution spaces. Providence, R.I., USA: American Mathematical Society, 1991.

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Mooney, Jayne. The prevalence and social distribution of domestic violence: An analysis of theory and method. London: Middlesex University, 1994.

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Wesselman, A. M. The population-sample decomposition method: A distribution-free estimation technique for minimum distance parameters. Dordrecht: M. Nijhoff, 1987.

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Arya, V. K. Finite element elastic-plastic-creep and cyclic life analysis of a cowl lip. [Washington, D.C.]: National Aeronautics and Space Administration, 1990.

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Srivastava, M. S. Saddlepoint method for obtaining tail probability of Wilk's likelihood ratio test. Toronto: University of Toronto, Dept. of Statistics, 1988.

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Hohn, Aleta A. Design for a multiple-method approach to determine stock structure of bottlenose dolphins in the mid-Atlantic: Report of a workshop, 11-12 February 1997. Beaufort, N.C: U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Science Center, Beaufort Laboratory, 1997.

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Hohn, Aleta A. Design for a multiple-method approach to determine stock structure of bottlenose dolphins in the mid-Atlantic: Report of a workshop, 11-12 February 1997. Beaufort, N.C: U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Science Center, Beaufort Laboratory, 1997.

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Kumar, A. A procedure for 3-D contact stress analysis of spiral bevel gears. [Washington, DC]: National Aeronautics and Space Administration, 1994.

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Kumar, A. A procedure for 3-D contact stress analysis of spiral bevel gears. [Washington, DC]: National Aeronautics and Space Administration, 1994.

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Book chapters on the topic "Distribution analysis method"

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Podder, Debabrata, and Santanu Chatterjee. "Moment Distribution Method." In Introduction to Structural Analysis, 327–52. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003081227-22.

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Spencer, W. J. "The Moment Distribution Method." In Fundamental Structural Analysis, 119–46. New York, NY: Springer New York, 1988. http://dx.doi.org/10.1007/978-1-4757-2006-8_5.

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Spencer, W. J. "The Moment Distribution Method." In Fundamental Structural Analysis, 119–46. London: Macmillan Education UK, 1988. http://dx.doi.org/10.1007/978-1-349-19582-4_5.

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Holsworth, R. M., Theodore Provder, and J. J. Stansbrey. "External-Gradient-Formation Method for Disc Centrifuge Photosedimentometric Particle Size Distribution Analysis." In Particle Size Distribution, 191–201. Washington, DC: American Chemical Society, 1987. http://dx.doi.org/10.1021/bk-1987-0332.ch013.

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Kersting, William H., and Robert J. Kerestes. "Balanced System Method of Analysis." In Distribution System Modeling and Analysis with MATLAB® and WindMil®, 37–53. 5th ed. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003261094-3.

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Papusoi, Cristian, Alexandru Stancu, and Constantin Papusoi. "Magnetic Method for Anisotropy Axis Distribution Analysis." In Magnetic Storage Systems Beyond 2000, 243–46. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-0624-8_16.

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Ariaratnam, S. T. "On the Moment Distribution Method of Structural Analysis." In Trends in Structural Mechanics, 353–56. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5476-5_34.

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Mir, Bashir Ahmed. "Particle Size Distribution Analysis by the Hydrometer Method." In Manual of Geotechnical Laboratory Soil Testing, 73–98. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003200260-5.

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Nakanishi, Tomoko M. "Element-Specific Distribution in a Plant." In Novel Plant Imaging and Analysis, 75–107. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4992-6_3.

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AbstractFor the first stage of the study of the elements, the distribution of the element within the plant tissue was presented employing neutron activation analysis (NAA). Since NAA allows nondestructive analysis of the elements in the sample, this is the only method to measure the absolute amount of elements in the sample.The results showed that the element-specific profile varied throughout the whole plant, and this distribution tendency remained similar throughout development. There were many junctions of element-specific concentrations between the tissues, suggesting barriers to the movement of the elements. Generally, heavy elements tended to accumulate in roots, except for Mn and Cr. Of the elements measured, Ca and Mg showed changes in concentration with the circadian rhythm. Since the amount of the element in a plant reflects the features of the soil where the plant grows, multielement analysis of the plant could specify the site of the agricultural products produced.Before addressing the development of a real-time RI imaging system (RRIS), the production of RIs for essential elements for plant nutrition, 28Mg and 42K, is presented. The reason why concentrating on RIs is because when we examine the history of plant research, physiological research on the elements without available radioisotopes has not been well developed. For example, the boron (B) transporter was recently found and the study of B in plants is far behind compared to the other elements.Therefore, we developed a preparation method for elements whose available RIs were not previously employed in plant research, 28Mg and 42K. They are the radioisotopes we prepared and a root absorption study using 28Mg as a tracer is presented as an example. It was found that the orientation of Mg transfer was different according to the site of the root where Mg was absorbed. The specific role of Mg has not yet been clarified by florescent imaging because the overwhelming amount of Ca makes it difficult to distinguish Mg and Ca.
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Sivakumar, P., and Ram Kailash Prasad. "Analysis of Water Distribution Network Using Epanet and Vertex Method." In Urban Hydrology, Watershed Management and Socio-Economic Aspects, 227–39. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-40195-9_18.

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Conference papers on the topic "Distribution analysis method"

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García, Vicente J., Enrique Cabrera, and Enrique Cabrera, Jr. "The Minimum Night Flow Method Revisited." In Eighth Annual Water Distribution Systems Analysis Symposium (WDSA). Reston, VA: American Society of Civil Engineers, 2008. http://dx.doi.org/10.1061/40941(247)35.

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Cuimei, Li, and Liu Suiqing. "Water Distribution Systems Evaluating Method Based on Value Engineering: Case Study." In Eighth Annual Water Distribution Systems Analysis Symposium (WDSA). Reston, VA: American Society of Civil Engineers, 2008. http://dx.doi.org/10.1061/40941(247)28.

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Jacobsen, Laura B., Mao Fang, and John Chan. "A DBP Control Method Using Localized Treatment and Distribution System Modeling." In Eighth Annual Water Distribution Systems Analysis Symposium (WDSA). Reston, VA: American Society of Civil Engineers, 2008. http://dx.doi.org/10.1061/40941(247)138.

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van Zyl, Jakobus E., Prabhat Kumar, and Mayank Gupta. "A Two Point Linearization Method for Snapshot Simulation of Water Distribution Systems." In Eighth Annual Water Distribution Systems Analysis Symposium (WDSA). Reston, VA: American Society of Civil Engineers, 2008. http://dx.doi.org/10.1061/40941(247)73.

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Wu, Zheng Yi, Richard Burrows, John Moorcroft, Neil Croxton, and Suttipan Limanond. "Pressure-Dependent Leakage Detection Method Compared with Conventional Techniques." In 12th Annual Conference on Water Distribution Systems Analysis (WDSA). Reston, VA: American Society of Civil Engineers, 2011. http://dx.doi.org/10.1061/41203(425)98.

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Ghimire, Santosh R., and Brian D. Barkdoll. "Heuristic Method for the Battle of the Water Network Sensors: Demand Based Approach." In Eighth Annual Water Distribution Systems Analysis Symposium (WDSA). Reston, VA: American Society of Civil Engineers, 2008. http://dx.doi.org/10.1061/40941(247)102.

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Qian, Xiaodong, Zhen Li, Zhi-Xin Li, and Zhiguang He. "Virtual Distribution and Mixing Entransy Analysis Method." In The 15th International Heat Transfer Conference. Connecticut: Begellhouse, 2014. http://dx.doi.org/10.1615/ihtc15.opt.008602.

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Creaco, Enrico, Marco Franchini, and Stefano Alvisi. "A Fast New Method for Segment Identification in Water Distribution Systems." In 12th Annual Conference on Water Distribution Systems Analysis (WDSA). Reston, VA: American Society of Civil Engineers, 2011. http://dx.doi.org/10.1061/41203(425)22.

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Ning, Zhou, Feng Guang, Zhao Zimo, Yu Kun, Yu Mingqi, and Zeng Xiangjun. "Personal Electric Shock Situation Analysis Method for Distribution Network." In 2018 China International Conference on Electricity Distribution (CICED). IEEE, 2018. http://dx.doi.org/10.1109/ciced.2018.8592377.

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Beguery, P. "Method for harmonic simulation in power distribution network and centralised active filtering analysis." In 14th International Conference and Exhibition on Electricity Distribution (CIRED 1997 - Distributing Power for the Millennium). IEE, 1997. http://dx.doi.org/10.1049/cp:19970502.

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Reports on the topic "Distribution analysis method"

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Ravazdezh, Faezeh, Julio A. Ramirez, and Ghadir Haikal. Improved Live Load Distribution Factors for Use in Load Rating of Older Slab and T-Beam Reinforced Concrete Bridges. Purdue University, 2021. http://dx.doi.org/10.5703/1288284317303.

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This report describes a methodology for demand estimate through the improvement of load distribution factors in reinforced concrete flat-slab and T-beam bridges. The proposed distribution factors are supported on three-dimensional (3D) Finite Element (FE) analysis tools. The Conventional Load Rating (CLR) method currently in use by INDOT relies on a two-dimensional (2D) analysis based on beam theory. This approach may overestimate bridge demand as the result of neglecting the presence of parapets and sidewalks present in these bridges. The 3D behavior of a bridge and its response could be better modeled through a 3D computational model by including the participation of all elements. This research aims to investigate the potential effect of railings, parapets, sidewalks, and end-diaphragms on demand evaluation for purposes of rating reinforced concrete flat-slab and T-beam bridges using 3D finite element analysis. The project goal is to improve the current lateral load distribution factor by addressing the limitations resulting from the 2D analysis and ignoring the contribution of non-structural components. Through a parametric study of the slab and T-beam bridges in Indiana, the impact of selected parameters on demand estimates was estimated, and modifications to the current load distribution factors in AASHTO were proposed.
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Bigl, Matthew, Samuel Beal, and Charles Ramsey. Determination of residual low-order detonation particle characteristics from Composition B mortar rounds. Engineer Research and Development Center (U.S.), August 2022. http://dx.doi.org/10.21079/11681/45260.

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Empirical measurements of the spatial distribution, particle-size distribution, mass, morphology, and energetic composition of particles from low-order (LO) detonations are critical to accurately characterizing environ-mental impacts on military training ranges. This study demonstrated a method of generating and characterizing LO-detonation particles, previously applied to insensitive munitions, to 81 mm mortar rounds containing the conventional explosive formulation Composition B. The three sampled rounds had estimated detonation efficiencies ranging from 64% to 82% as measured by sampled residual energetic material. For all sampled rounds, energetic deposition rates were highest closer to the point of detonation; however, the mass per radial meter varied. The majority of particles (>60%), by mass, were <2 mm in size. However, the spatial distribution of the <2 mm particles from the point of detonation varied be-tween the three sampled rounds. In addition to the particle-size-distribution results, several method performance observations were made, including command-detonation configurations, sampling quality control, particle-shape influence on laser-diffraction particle-size analysis (LD-PSA), and energetic purity trends. Overall, this study demonstrated the successful characterization of Composition B LO-detonation particles from command detonation through combined analysis by LD-PSA and sieving.
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Warrick, Arthur W., Gideon Oron, Mary M. Poulton, Rony Wallach, and Alex Furman. Multi-Dimensional Infiltration and Distribution of Water of Different Qualities and Solutes Related Through Artificial Neural Networks. United States Department of Agriculture, January 2009. http://dx.doi.org/10.32747/2009.7695865.bard.

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The project exploits the use of Artificial Neural Networks (ANN) to describe infiltration, water, and solute distribution in the soil during irrigation. It provides a method of simulating water and solute movement in the subsurface which, in principle, is different and has some advantages over the more common approach of numerical modeling of flow and transport equations. The five objectives were (i) Numerically develop a database for the prediction of water and solute distribution for irrigation; (ii) Develop predictive models using ANN; (iii) Develop an experimental (laboratory) database of water distribution with time; within a transparent flow cell by high resolution CCD video camera; (iv) Conduct field studies to provide basic data for developing and testing the ANN; and (v) Investigate the inclusion of water quality [salinity and organic matter (OM)] in an ANN model used for predicting infiltration and subsurface water distribution. A major accomplishment was the successful use of Moment Analysis (MA) to characterize “plumes of water” applied by various types of irrigation (including drip and gravity sources). The general idea is to describe the subsurface water patterns statistically in terms of only a few (often 3) parameters which can then be predicted by the ANN. It was shown that ellipses (in two dimensions) or ellipsoids (in three dimensions) can be depicted about the center of the plume. Any fraction of water added can be related to a ‘‘probability’’ curve relating the size of the ellipse (or ellipsoid) that contains that amount of water. The initial test of an ANN to predict the moments (and hence the water plume) was with numerically generated data for infiltration from surface and subsurface drip line and point sources in three contrasting soils. The underlying dataset consisted of 1,684,500 vectors (5 soils×5 discharge rates×3 initial conditions×1,123 nodes×20 print times) where each vector had eleven elements consisting of initial water content, hydraulic properties of the soil, flow rate, time and space coordinates. The output is an estimate of subsurface water distribution for essentially any soil property, initial condition or flow rate from a drip source. Following the formal development of the ANN, we have prepared a “user-friendly” version in a spreadsheet environment (in “Excel”). The input data are selected from appropriate values and the output is instantaneous resulting in a picture of the resulting water plume. The MA has also proven valuable, on its own merit, in the description of the flow in soil under laboratory conditions for both wettable and repellant soils. This includes non-Darcian flow examples and redistribution and well as infiltration. Field experiments were conducted in different agricultural fields and various water qualities in Israel. The obtained results will be the basis for the further ANN models development. Regions of high repellence were identified primarily under the canopy of various orchard crops, including citrus and persimmons. Also, increasing OM in the applied water lead to greater repellency. Major scientific implications are that the ANN offers an alternative to conventional flow and transport modeling and that MA is a powerful technique for describing the subsurface water distributions for normal (wettable) and repellant soil. Implications of the field measurements point to the special role of OM in affecting wettability, both from the irrigation water and from soil accumulation below canopies. Implications for agriculture are that a modified approach for drip system design should be adopted for open area crops and orchards, and taking into account the OM components both in the soil and in the applied waters.
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Derbentsev, V., A. Ganchuk, and Володимир Миколайович Соловйов. Cross correlations and multifractal properties of Ukraine stock market. Politecnico di Torino, 2006. http://dx.doi.org/10.31812/0564/1117.

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Recently the statistical characterizations of financial markets based on physics concepts and methods attract considerable attentions. The correlation matrix formalism and concept of multifractality are used to study temporal aspects of the Ukraine Stock Market evolution. Random matrix theory (RMT) is carried out using daily returns of 431 stocks extracted from database time series of prices the First Stock Trade System index (www.kinto.com) for the ten-year period 1997-2006. We find that a majority of the eigenvalues of C fall within the RMT bounds for the eigenvalues of random correlation matrices. We test the eigenvalues of C within the RMT bound for universal properties of random matrices and find good agreement with the results for the Gaussian orthogonal ensemble of random matrices—implying a large degree of randomness in the measured cross-correlation coefficients. Further, we find that the distribution of eigenvector components for the eigenvectors corresponding to the eigenvalues outside the RMT bound display systematic deviations from the RMT prediction. We analyze the components of the deviating eigenvectors and find that the largest eigenvalue corresponds to an influence common to all stocks. Our analysis of the remaining deviating eigenvectors shows distinct groups, whose identities correspond to conventionally identified business sectors. Comparison with the Mantegna minimum spanning trees method gives a satisfactory consent. The found out the pseudoeffects related to the artificial unchanging areas of price series come into question We used two possible procedures of analyzing multifractal properties of a time series. The first one uses the continuous wavelet transform and extracts scaling exponents from the wavelet transform amplitudes over all scales. The second method is the multifractal version of the detrended fluctuation analysis method (MF-DFA). The multifractality of a time series we analysed by means of the difference of values singularity stregth (or Holder exponent) ®max and ®min as a suitable way to characterise multifractality. Singularity spectrum calculated from daily returns using a sliding 250 day time window in discrete steps of 1. . . 10 days. We discovered that changes in the multifractal spectrum display distinctive pattern around significant “drawdowns”. Finally, we discuss applications to the construction of crushes precursors at the financial markets.
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Regan, Jack, Julie Bryant, and Craig Weinschenk. Analysis of the Coordination of Suppression and Ventilation in Single-Family Homes. UL Firefighter Safety Research Institute, March 2020. http://dx.doi.org/10.54206/102376/slzh7498.

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Prior full-scale research with the fire service was primarily designed to isolate specific tactics, most often either ventilation or suppression, which allowed researchers to develop science-based recommendations related to the specific components of fireground operations studied in relatively controlled conditions. The current project went beyond earlier research by conducting twenty experiments in eight acquired, single-family residential structures and that combined fireground tactics to quantify the impact of coordination between ventilation and suppression actions. This experimental series included second-story bedroom fires (14 experiments) and first-floor kitchen fires (6 experiments). The main control variables studied included the position of initial application of water, the ventilation method, and the timing of ventilation relative to water application. The ventilation tactics examined in these experiments included horizontal, vertical, positive pressure, and hydraulic ventilation, while the suppression tactics included both interior water application and initial exterior water application followed by interior water application. While some elements of the experiments (e.g. structure floor plan and weather) resulted in increased variability, the lessons learned highlighted the importance of having a systematic approach to the implementation of tactics. Most importantly, there was no meaningful increase in temperature outside of fire rooms when ventilation tactics were executed in coordination with (shortly after or shortly before) the onset of suppression. The effectiveness of suppression actions in extinguishing the fire were dependent on the ability of those actions to 1) cool surfaces in the fire room and 2) wet unburned fuel. Exterior suppression actions on second-floor bedroom fires resulted in a decrease in temperatures throughout the second floor, followed by regrowth prior to final suppression through interior streams. When exterior suppression was performed on first-floor kitchen fires, where more complete fuel wetting was possible, regrowth was not observed prior to interior suppression. When surface cooling or fuel wetting are not possible due to the elevation of the fire room, missing ceiling, or obstacles, firefighters should consider alternative means of water distribution to improve the effectiveness of suppression actions from outside the fire room. Suppression actions, whether interior or exterior, generally resulted in a decrease in temperatures and gas concentrations at locations where occupants may potentially be located. Conditions improved most quickly at locations closest in proximity to the inlet of the flow path established between the front door and the fire room. For this reason, opening an exterior door to gain access should be thought of as an important ventilation action, both in terms of its potential to cause fire growth and its potential to improve conditions for potentially trapped occupants. After effective suppression, structure ventilation operations should similarly be cognizant of gas flows, with the aim of establishing flow throughout all areas where occupants may be located.
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yu, luyou, jinping yang, xi meng, and yanhua ling. Efficacy and safety of acupuncture combined with probiotics in the treatment of type 2 diabetes mellitus with intestinal microbiota disorder: A protocol for systematic review and meta analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, September 2022. http://dx.doi.org/10.37766/inplasy2022.9.0001.

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Review question / Objective: Efficacy and safety of acupuncture combined with probiotics in the treatment of type 2 diabetes mellitus with intestinal microbiota disorder: A protocol for systematic review and meta analysis. Eligibility criteria: 1.The literatures of type 2 diabetes patients were included without restriction on gender, age, race, disease course and blood glucose control of the subjects. 2. The relevant literatures included in human intestinal flora do not strictly restrict the test methods and key indicators of fecal specimens. 3. Relevant literatures with no statistically significant difference in general data between the experimental group and the control group were included. 4.There is no restriction on whether blind method or distributive hiding method is used to include Chinese and English literatures whose research type is correlation study. 5. References that clearly indicated standard deviation (SD), mean value or which could be calculated by formula were included.
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Gantzer, Clark J., Shmuel Assouline, and Stephen H. Anderson. Synchrotron CMT-measured soil physical properties influenced by soil compaction. United States Department of Agriculture, February 2006. http://dx.doi.org/10.32747/2006.7587242.bard.

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Methods to quantify soil conditions of pore connectivity, tortuosity, and pore size as altered by compaction were done. Air-dry soil cores were scanned at the GeoSoilEnviroCARS sector at the Advanced Photon Source for x-ray computed microtomography of the Argonne facility. Data was collected on the APS bending magnet Sector 13. Soil sample cores 5- by 5-mm were studied. Skeletonization algorithms in the 3DMA-Rock software of Lindquist et al. were used to extract pore structure. We have numerically investigated the spatial distribution for 6 geometrical characteristics of the pore structure of repacked Hamra soil from three-dimensional synchrotron computed microtomography (CMT) computed tomographic images. We analyzed images representing cores volumes 58.3 mm³ having average porosities of 0.44, 0.35, and 0.33. Cores were packed with < 2mm and < 0.5mm sieved soil. The core samples were imaged at 9.61-mm resolution. Spatial distributions for pore path length and coordination number, pore throat size and nodal pore volume obtained. The spatial distributions were computed using a three-dimensional medial axis analysis of the void space in the image. We used a newly developed aggressive throat computation to find throat and pore partitioning for needed for higher porosity media such as soil. Results show that the coordination number distribution measured from the medial axis were reasonably fit by an exponential relation P(C)=10⁻C/C0. Data for the characteristic area, were also reasonably well fit by the relation P(A)=10⁻ᴬ/ᴬ0. Results indicates that compression preferentially affects the largest pores, reducing them in size. When compaction reduced porosity from 44% to 33%, the average pore volume reduced by 30%, and the average pore-throat area reduced by 26%. Compaction increased the shortest paths interface tortuosity by about 2%. Soil structure alterations induced by compaction using quantitative morphology show that the resolution is sufficient to discriminate soil cores. This study shows that analysis of CMT can provide information to assist in assessment of soil management to ameliorate soil compaction.
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Gradín, Carlos. WIID Companion (March 2021): global income distribution. UNU-WIDER, March 2021. http://dx.doi.org/10.35188/unu-wider/wtn/2021-6.

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This document is part of a series of technical notes describing the compilation of a new companion database that complements the UNU-WIDER World Income Inequality Database. It aims at facilitating the analysis of inequality as well as progress in achieving the global goal of reducing inequality within and across countries. This new dataset includes an annual series reporting the income distribution at the percentile level for all citizens in the world, regardless of where they live, from 1950 to the present. The global distribution is displayed along with the country-level information used to produce it. The dataset also includes estimates of various global absolute and relative inequality measures, and the income share of key population groups. All estimates are further disaggregated by the contribution of inequalities within and between countries, as well as by each country’s geographical region and income group. While previous technical notes described the selection of country income distribution series and the integration and standardization process to overcome the heterogeneity in original welfare concepts and other methods, I here describe all the necessary additional steps and assumptions made to construct the new global dataset.
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Gradín, Carlos. WIID Companion (March 2021): integrated and standardized series. UNU-WIDER, March 2021. http://dx.doi.org/10.35188/unu-wider/wtn/2021-5.

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This document is part of a series of technical notes describing the compilation of a new companion database that complements the World Income Inequality Database. It aims at facilitating the analysis of inequality as well as progress in achieving the global goal of reducing inequality within and across countries. This new dataset also includes an annual series reporting the income distribution at the percentile level for all citizens in the world, regardless of where they live, since 1950 to present. A previous note described the selection of income distribution series. Since these series may differ across welfare concepts and other methods used, this technical note describes the second stage, constructing integrated and standardized country series. It discusses all the necessary adjustments conducted to construct the final series for each country, with consistent estimates of the distribution of net income per capita over the entire period for which information is available. This is mainly divided into two stages. First, integrating country series by interlinking series that overlap over time, then using a more general regression-based approach.
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Galili, Naftali, Roger P. Rohrbach, Itzhak Shmulevich, Yoram Fuchs, and Giora Zauberman. Non-Destructive Quality Sensing of High-Value Agricultural Commodities Through Response Analysis. United States Department of Agriculture, October 1994. http://dx.doi.org/10.32747/1994.7570549.bard.

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The objectives of this project were to develop nondestructive methods for detection of internal properties and firmness of fruits and vegetables. One method was based on a soft piezoelectric film transducer developed in the Technion, for analysis of fruit response to low-energy excitation. The second method was a dot-matrix piezoelectric transducer of North Carolina State University, developed for contact-pressure analysis of fruit during impact. Two research teams, one in Israel and the other in North Carolina, coordinated their research effort according to the specific objectives of the project, to develop and apply the two complementary methods for quality control of agricultural commodities. In Israel: An improved firmness testing system was developed and tested with tropical fruits. The new system included an instrumented fruit-bed of three flexible piezoelectric sensors and miniature electromagnetic hammers, which served as fruit support and low-energy excitation device, respectively. Resonant frequencies were detected for determination of firmness index. Two new acoustic parameters were developed for evaluation of fruit firmness and maturity: a dumping-ratio and a centeroid of the frequency response. Experiments were performed with avocado and mango fruits. The internal damping ratio, which may indicate fruit ripeness, increased monotonically with time, while resonant frequencies and firmness indices decreased with time. Fruit samples were tested daily by destructive penetration test. A fairy high correlation was found in tropical fruits between the penetration force and the new acoustic parameters; a lower correlation was found between this parameter and the conventional firmness index. Improved table-top firmness testing units, Firmalon, with data-logging system and on-line data analysis capacity have been built. The new device was used for the full-scale experiments in the next two years, ahead of the original program and BARD timetable. Close cooperation was initiated with local industry for development of both off-line and on-line sorting and quality control of more agricultural commodities. Firmalon units were produced and operated in major packaging houses in Israel, Belgium and Washington State, on mango and avocado, apples, pears, tomatoes, melons and some other fruits, to gain field experience with the new method. The accumulated experimental data from all these activities is still analyzed, to improve firmness sorting criteria and shelf-life predicting curves for the different fruits. The test program in commercial CA storage facilities in Washington State included seven apple varieties: Fuji, Braeburn, Gala, Granny Smith, Jonagold, Red Delicious, Golden Delicious, and D'Anjou pear variety. FI master-curves could be developed for the Braeburn, Gala, Granny Smith and Jonagold apples. These fruits showed a steady ripening process during the test period. Yet, more work should be conducted to reduce scattering of the data and to determine the confidence limits of the method. Nearly constant FI in Red Delicious and the fluctuations of FI in the Fuji apples should be re-examined. Three sets of experiment were performed with Flandria tomatoes. Despite the complex structure of the tomatoes, the acoustic method could be used for firmness evaluation and to follow the ripening evolution with time. Close agreement was achieved between the auction expert evaluation and that of the nondestructive acoustic test, where firmness index of 4.0 and more indicated grade-A tomatoes. More work is performed to refine the sorting algorithm and to develop a general ripening scale for automatic grading of tomatoes for the fresh fruit market. Galia melons were tested in Israel, in simulated export conditions. It was concluded that the Firmalon is capable of detecting the ripening of melons nondestructively, and sorted out the defective fruits from the export shipment. The cooperation with local industry resulted in development of automatic on-line prototype of the acoustic sensor, that may be incorporated with the export quality control system for melons. More interesting is the development of the remote firmness sensing method for sealed CA cool-rooms, where most of the full-year fruit yield in stored for off-season consumption. Hundreds of ripening monitor systems have been installed in major fruit storage facilities, and being evaluated now by the consumers. If successful, the new method may cause a major change in long-term fruit storage technology. More uses of the acoustic test method have been considered, for monitoring fruit maturity and harvest time, testing fruit samples or each individual fruit when entering the storage facilities, packaging house and auction, and in the supermarket. This approach may result in a full line of equipment for nondestructive quality control of fruits and vegetables, from the orchard or the greenhouse, through the entire sorting, grading and storage process, up to the consumer table. The developed technology offers a tool to determine the maturity of the fruits nondestructively by monitoring their acoustic response to mechanical impulse on the tree. A special device was built and preliminary tested in mango fruit. More development is needed to develop a portable, hand operated sensing method for this purpose. In North Carolina: Analysis method based on an Auto-Regressive (AR) model was developed for detecting the first resonance of fruit from their response to mechanical impulse. The algorithm included a routine that detects the first resonant frequency from as many sensors as possible. Experiments on Red Delicious apples were performed and their firmness was determined. The AR method allowed the detection of the first resonance. The method could be fast enough to be utilized in a real time sorting machine. Yet, further study is needed to look for improvement of the search algorithm of the methods. An impact contact-pressure measurement system and Neural Network (NN) identification method were developed to investigate the relationships between surface pressure distributions on selected fruits and their respective internal textural qualities. A piezoelectric dot-matrix pressure transducer was developed for the purpose of acquiring time-sampled pressure profiles during impact. The acquired data was transferred into a personal computer and accurate visualization of animated data were presented. Preliminary test with 10 apples has been performed. Measurement were made by the contact-pressure transducer in two different positions. Complementary measurements were made on the same apples by using the Firmalon and Magness Taylor (MT) testers. Three-layer neural network was designed. 2/3 of the contact-pressure data were used as training input data and corresponding MT data as training target data. The remaining data were used as NN checking data. Six samples randomly chosen from the ten measured samples and their corresponding Firmalon values were used as the NN training and target data, respectively. The remaining four samples' data were input to the NN. The NN results consistent with the Firmness Tester values. So, if more training data would be obtained, the output should be more accurate. In addition, the Firmness Tester values do not consistent with MT firmness tester values. The NN method developed in this study appears to be a useful tool to emulate the MT Firmness test results without destroying the apple samples. To get more accurate estimation of MT firmness a much larger training data set is required. When the larger sensitive area of the pressure sensor being developed in this project becomes available, the entire contact 'shape' will provide additional information and the neural network results would be more accurate. It has been shown that the impact information can be utilized in the determination of internal quality factors of fruit. Until now,
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