A Stochastic Study on the Distribution Parameters of Random Individual Walking Excitations

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

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ESTIMATION OF THE T-YEAR SPECIFIC DISCHARGE USING THE REGIONALISED SKEWNESS COEFFICIENT OF THE LOG-PEARSON TYPE III DISTRIBUTION

Proceedings of the XXVII Conference of the Danubian Countries on Hydrological Forecasting and Hydrological Bases of Water Management ◽

10.15407/uhmi.conference.01.09 ◽

2020 ◽

Author(s):

Jakub Mészáros ◽

◽

Pavol Miklánek ◽

Pavla Pekárová ◽

◽

...

Keyword(s):

River Basin ◽

Type Iii ◽

River Region ◽

Pearson Type ◽

Skewness Coefficient ◽

Distribution Parameters ◽

Design Values ◽

Specific Discharge ◽

Morava River ◽

Pearson Type Iii Distribution

In this paper the results are presented of estimation of T-year specific discharge of several streams in two regions in Slovakia. The Qmax time series used in the study were observed at water gauges from lowland Slovak part of the Morava River basin, and from the mountainous Belá River basin. For estimating the design values, we have studied the use of only one type of probability distribution, namely the Log-Pearson Type III Distribution (LP3 distribution). The use of only one type of distribution brings several benefits, e.g. possibility of the regionalization of the distribution parameters (in this study skew coefficient). In the first step the design values of the specific discharge series qmax (with historical data) were estimated and regional skew coefficients Gr of the LP3 distribution were computed. Regional skewness coefficient Gr was estimated to be 0.38 in the Morava River region, and 0.73 in the Belá River region. In many cases the estimate of the 1000-year specific discharge is two times higher than the value of the 100-year specific discharge. Then we have derived the empirical relations between station skew coefficient G and the elevation of the water gauge. In the second step we have derived the empirical relationships between 1000-years specific discharge q1000 and the elevation of the water gauge for both regions separately. The derived empirical regional equations can be used to estimate the 1000-years specific discharge of other streams in the region.

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Using Imperfectly Elicited Fractiles for the Estimation of Probability Distribution Parameters

SSRN Electronic Journal ◽

10.2139/ssrn.2160349 ◽

2012 ◽

Cited By ~ 1

Author(s):

Saurabh Bansal ◽

Genaro Gutierrez

Keyword(s):

Probability Distribution ◽

Distribution Parameters

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ABOUT INVARIANCE OF ANGLE NOISE DISTRIBUTION PARAMETERS BY AN ARBITRARY N-POINT GEOMETRIC MODEL TO VIEWING ANGLE

Issues of radio electronics ◽

10.21778/2218-5453-2019-4-32-35 ◽

2019 ◽

pp. 32-35

Author(s):

V. V. Artyushenko ◽

A. V. Nikulin

Keyword(s):

Regular Polygon ◽

Geometric Model ◽

Sea Surface ◽

Noise Distribution ◽

Viewing Angle ◽

Distributed Objects ◽

Software Complex ◽

The Earth ◽

Distribution Parameters ◽

Equal Power

In this article we consider a problem of reliable modeling of echo signals and angle noise of distributed objects using twodimensional geometric models with random statistically unrelated signals. The conditions that ensure the invariance of distribution parameters of the angle noise generated by an arbitrary N-point configuration of a two-dimensional geometric model are obtained. In the particular case of a model whose emitters are supplied with signals of equal power, the conditions of invariance are reduced to the location of the model points on the plane in the form of a regular polygon. These results can be used to synthesize mathematical models used for simulating reflections from distributed objects and for developing a hardware-software complex for the simulation of electromagnetic fields reflected from the Earth surface, atmospheric inhomogeneities, the sea surface, etc.

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Measuring Hydrometeors Using a Precipitation Microphysical Characteristics Sensor: Sampling Effect of Different Bin Sizes on Drop Size Distribution Parameters

Advances in Meteorology ◽

10.1155/2018/9727345 ◽

2018 ◽

Vol 2018 ◽

pp. 1-15 ◽

Cited By ~ 3

Author(s):

Xichuan Liu ◽

Taichang Gao ◽

Yuntao Hu ◽

Xiaojian Shu

Keyword(s):

Drop Size ◽

Rain Rate ◽

Monte Carlo Model ◽

Rain Gauge ◽

Sampling Schemes ◽

Distribution Parameters ◽

Optimum Sampling ◽

Simulation Results ◽

The Impact ◽

Good Agreement

In order to improve the measurement of precipitation microphysical characteristics sensor (PMCS), the sampling process of raindrops by PMCS based on a particle-by-particle Monte-Carlo model was simulated to discuss the effect of different bin sizes on DSD measurement, and the optimum sampling bin sizes for PMCS were proposed based on the simulation results. The simulation results of five sampling schemes of bin sizes in four rain-rate categories show that the raw capture DSD has a significant fluctuation variation influenced by the capture probability, whereas the appropriate sampling bin size and width can reduce the impact of variation of raindrop number on DSD shape. A field measurement of a PMCS, an OTT PARSIVEL disdrometer, and a tipping bucket rain Gauge shows that the rain-rate and rainfall accumulations have good consistencies between PMCS, OTT, and Gauge; the DSD obtained by PMCS and OTT has a good agreement; the probability of N0, μ, and Λ shows that there is a good agreement between the Gamma parameters of PMCS and OTT; the fitted μ-Λ and Z-R relationship measured by PMCS is close to that measured by OTT, which validates the performance of PMCS on rain-rate, rainfall accumulation, and DSD related parameters.

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Interpretable Variational Graph Autoencoder with Noninformative Prior

Future Internet ◽

10.3390/fi13020051 ◽

2021 ◽

Vol 13 (2) ◽

pp. 51

Author(s):

Lili Sun ◽

Xueyan Liu ◽

Min Zhao ◽

Bo Yang

Keyword(s):

Latent Variables ◽

Latent Variable ◽

Expert Knowledge ◽

Structural Information ◽

Standard Normal Distribution ◽

Noninformative Prior ◽

Latent Space ◽

Distribution Parameters ◽

Standard Normal ◽

Low Dimensional

Variational graph autoencoder, which can encode structural information and attribute information in the graph into low-dimensional representations, has become a powerful method for studying graph-structured data. However, most existing methods based on variational (graph) autoencoder assume that the prior of latent variables obeys the standard normal distribution which encourages all nodes to gather around 0. That leads to the inability to fully utilize the latent space. Therefore, it becomes a challenge on how to choose a suitable prior without incorporating additional expert knowledge. Given this, we propose a novel noninformative prior-based interpretable variational graph autoencoder (NPIVGAE). Specifically, we exploit the noninformative prior as the prior distribution of latent variables. This prior enables the posterior distribution parameters to be almost learned from the sample data. Furthermore, we regard each dimension of a latent variable as the probability that the node belongs to each block, thereby improving the interpretability of the model. The correlation within and between blocks is described by a block–block correlation matrix. We compare our model with state-of-the-art methods on three real datasets, verifying its effectiveness and superiority.

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Fracture System and Rock-Mass Characterization by Borehole Camera Surveying: Application in Dimension Stone Investigations in Geologically Complex Structures

Applied Sciences ◽

10.3390/app11020764 ◽

2021 ◽

Vol 11 (2) ◽

pp. 764

Author(s):

Ivica Pavičić ◽

Ivo Galić ◽

Mišo Kucelj ◽

Ivan Dragičević

Keyword(s):

Rock Mass ◽

Fractured Rock ◽

Low Cost ◽

Fracture Pattern ◽

Dimension Stone ◽

Rock Mass Characterization ◽

Size And Shape ◽

Distribution Parameters ◽

Borehole Camera ◽

Fracture Distribution

The successful exploration of dimension stone mainly depends on the quality, size, and shape of extractable blocks of dimension stone. The investigated area is in the Pelješac Peninsula (Croatia), in the External Dinarides orogeny, built from thick carbonate succession, characterized by relatively small deposits of high-quality dimension stone. These conditions demand challenging geological investigations in the “pre-quarry” phase to find optimal quarry location. The size and shape of dimension stone blocks are mainly controlled by fracture pattern systems. In the rugged, covered terrains, it is very hard to obtain a satisfactory amount of fracture data from the surface, so it is necessary to collect them from the underground. Borehole camera technology can visualize the inner part of the rock mass and measure the fracture characteristics. The main conclusions are as follows: (1) the digital borehole camera technology provides a quick, effective, and low-cost geological survey of fractured rock mass; (2) statistical fracture distribution parameters, P10, fracture spacing, Volumetric Joint Count (Jv) based on borehole wall survey can reflect the integrity of rock mass, providing a solid decision-making base for further investment plans and dimension stone excavation method.

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