Sample Point Uniformity Using Discrepancy Measures

This paper revisits the link between assumed diameter distributions arising from horizontal point samples and their unbiased stand-based representation through weighted distribution theory. Examples are presented, which show that the assumption of a common shared parameter set between these two distributional forms, while theoretically valid, may not be reasonable in many operational cases. Simulation results are presented, which relate the conformity (or lack thereof) in these estimates to sampling intensity per point and the underlying shape of the population diameter distribution from which the sample point was drawn. In general, larger sample sizes per point are required to yield reliable parameter estimates than are generally taken for inventory purposes. In addition, a complimentary finding suggests that the more positively skewed the underlying distribution, the more trees per point are required for good parameter estimates.

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Sampling grid density and lime recommendation in an Oxisol

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v18n11p1142-1148 ◽

2014 ◽

Vol 18 (11) ◽

pp. 1142-1148 ◽

Cited By ~ 5

Author(s):

Eduardo L. Bottega ◽

Daniel M. de Queiroz ◽

Francisco A. C. Pinto ◽

Antonio M. de Oliveira Neto ◽

Cesar C. Vilar ◽

...

Keyword(s):

Soil Analysis ◽

Sample Point ◽

Brazilian Cerrado ◽

Mato Grosso ◽

Sampling Grid ◽

Sampling Points ◽

Regular Sampling ◽

Geostatistical Techniques ◽

Mato Grosso Do Sul ◽

Kriging Maps

The objective of this study was to evaluate the influence of different sampling grids density in the lime requirements in an Oxisol. The experiment was conducted at a rural property located in Sidrolândia city, Mato Grosso do Sul state, in the Brazilian ‘Cerrado’. In the soil attributes mapping, regular sampling grid was used consisting of 99 points, spread over an area of 90 ha. Other two grids (51 and 27 points) were derived by deleting lines or lines and points from the original one. Based on the results of soil analysis, the lime requirement at each sample point was calculated. Using geostatistical techniques the spatial variability of lime requirement was studied and grid configuration for each sample was tested. By kriging, maps were made. By reducing the number of sampling points, 11% of the experimental area showed an overestimation and 8% underestimation comparing with the lime requirement made using the highest sampling grid density.

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Research on sample point repairing for free-form curved surface

International Journal of Modelling Identification and Control ◽

10.1504/ijmic.2014.064293 ◽

2014 ◽

Vol 22 (2) ◽

pp. 178

Author(s):

Jian wei Ma ◽

Fu ji Wang ◽

Zhen yuan Jia ◽

li Wei

Keyword(s):

Curved Surface ◽

Free Form ◽

Sample Point

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Improvements of Infrared Touch Screen Calibration Algorithm Based on Affine Transformation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.716-717.1341 ◽

2014 ◽

Vol 716-717 ◽

pp. 1341-1345

Author(s):

Wen Ming Guo ◽

Gang Wang

Keyword(s):

Affine Transformation ◽

Touch Screen ◽

The Other ◽

Pass Rate ◽

Sample Point ◽

Affine Transform ◽

Calibration Algorithm ◽

Windows 8

Because the affine transformation can realize the coordinate translation, rotation, scaling, it is applied to calibrate the touch screen. But,requirements for touch errors of Windows 8 is ±0.5mm,and the pass rate of sample point must reach 4%.Therefore, simply use the method of draw-point to collect the sample point has been unable to meet the requirement of accuracy. This paper tries to propose two improved calibration algorithm based on affine transform, one method use drawing lines instead of marking point, the other devides the screen into a plurality of areas to use multiple calibration. This two kind of methods can effectively improve the calibration precision.

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Bayesian Surrogate Learning for Uncertainty Analysis of Coupled Multidisciplinary Systems

Journal of Computing and Information Science in Engineering ◽

10.1115/1.4049994 ◽

2021 ◽

Vol 21 (4) ◽

Author(s):

Seyede Fatemeh Ghoreishi ◽

Mahdi Imani

Keyword(s):

Uncertainty Analysis ◽

Closed Form ◽

Uncertainty Propagation ◽

Uncertainty Reduction ◽

System Level ◽

Engineering Systems ◽

Sample Point ◽

Design Variables ◽

Multidisciplinary Systems ◽

Stationary Behavior

Abstract Engineering systems are often composed of many subsystems that interact with each other. These subsystems, referred to as disciplines, contain many types of uncertainty and in many cases are feedback-coupled with each other. In designing these complex systems, one needs to assess the stationary behavior of these systems for the sake of stability and reliability. This requires the system level uncertainty analysis of the multidisciplinary systems, which is often computationally intractable. To overcome this issue, techniques have been developed for capturing the stationary behavior of the coupled multidisciplinary systems through available data of individual disciplines. The accuracy and convergence of the existing techniques depend on a large amount of data from all disciplines, which are not available in many practical problems. Toward this, we have developed an adaptive methodology that adds the minimum possible number of samples from individual disciplines to achieve an accurate and reliable uncertainty propagation in coupled multidisciplinary systems. The proposed method models each discipline function via Gaussian process (GP) regression to derive a closed-form policy. This policy sequentially selects a new sample point that results in the highest uncertainty reduction over the distribution of the coupling design variables. The effectiveness of the proposed method is demonstrated in the uncertainty analysis of an aerostructural system and a coupled numerical example.

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Statistical methods in atmospheric dynamics: probability metrics and discrepancy measures as a means of defining balance

Large-Scale Atmosphere-Ocean Dynamics ◽

10.1017/cbo9780511549991.008 ◽

2002 ◽

pp. 342-370

Author(s):

S. Baigent ◽

J. Norbury

Keyword(s):

Statistical Methods ◽

Atmospheric Dynamics ◽

Probability Metrics ◽

Discrepancy Measures

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Application of scalable discrepancy measures for computer vision image segmentation tasks

10.1117/12.514938 ◽

2003 ◽

Author(s):

B. Belaroussi ◽

Christophe Odet ◽

Hugues Benoit-Cattin

Keyword(s):

Computer Vision ◽

Image Segmentation ◽

Discrepancy Measures

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Reply by author to discussion by Michael Schoenberger.

Geophysics ◽

10.1190/1.1486562 ◽

1968 ◽

Vol 33 (4) ◽

pp. 680-680

Author(s):

John P. Burg

Keyword(s):

Time Domain ◽

Convolution Operator ◽

Shift Operator ◽

Time Shift ◽

Weighted Sum ◽

Sample Point ◽

Shift Operators ◽

Point Operator

The principal assertion of Schoenberger’s discussion appears to be that (3), which is correctly derived from equations in Section IV and corresponds to a space shift, should instead be written as (4), corresponding to a space sample. However, the space‐convolution operator corresponding to a seismometer is indeed meant to be a space‐shift operator. An array of seismometers is used as a weighted sum of space‐shift operators, just as a time‐domain, sample‐point operator is made up of a weighted sum of time‐shift operators. Equation (5.2), which Schoenberger indicates as being related to his (4), actually comes from (3) with x and y set to zero.

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