Real-time precision measuring device of tree diameter growth

Abstract Many growth and yield models have used statistical probability distributions to estimate the diameter distribution of a stand at any age. Equations for approximating individual tree diameter growth and survival probabilities from dbh can be derived from these models. A general procedure for determining the functions is discussed and illustrated using a loblolly pine spacing study. The results from the spacing study show that it is possible to define tree diameter growth and survival probability functions from diameter distributions with an accuracy sufficient to obtain a link between the individual tree and diameter growth and yield models.

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Individual tree diameter growth modeling system for Dalat pine (Pinus dalatensis Ferré) of the upland mixed tropical forests

Forest Ecology and Management ◽

10.1016/j.foreco.2020.118612 ◽

2021 ◽

Vol 480 ◽

pp. 118612

Author(s):

Bao Huy ◽

Le Canh Nam ◽

Krishna P. Poudel ◽

Hailemariam Temesgen

Keyword(s):

Tropical Forests ◽

Growth Modeling ◽

Diameter Growth ◽

Individual Tree ◽

Tree Diameter

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Half division two-dimensional method for simple sinusoidal quantities parameters accurate measurement

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2021-4-16-21 ◽

2021 ◽

pp. 16-21

Author(s):

Kirill Yu. Solomentsev ◽

Vyacheslav I. Lachin ◽

Aleksandr E. Pasenchuk

Keyword(s):

Measuring Instruments ◽

Measured Signal ◽

Two Dimensional ◽

Measuring Device ◽

New Approach ◽

Precision Measuring ◽

Useful Signal ◽

Midpoint Method ◽

Order Of Magnitude ◽

Current Measuring

Several variants of half division two-dimensional method are proposed, which is the basis of a fundamentally new approach for constructing measuring instruments for sinusoidal or periodic electrical quantities. These measuring instruments are used in the diagnosis of electric power facilities. The most general variant, called midpoint method, is considered. The proposed midpoint method allows you to measure much smaller than using widespread methods, alternating currents or voltages, especially when changing the amplitude of the measured signal in very wide ranges, by 1–2 orders of magnitude. It is shown that using the midpoint method it is possible to suppress sinusoidal or periodic interference in the measuring path, in particular, to measure small alternating current when sinusoidal or periodic interference is 1–2 orders of magnitude higher than the useful signal. Based on the results of comparative tests, it was found that the current measuring device implementing the midpoint method is an order of magnitude more sensitive than the currently used high-precision measuring instruments.

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Improved sliding mode dynamic matrix control strategy: Application on spindle loading and precision measuring device based on piezoelectric actuator

Mechanical Systems and Signal Processing ◽

10.1016/j.ymssp.2021.108543 ◽

2022 ◽

Vol 167 ◽

pp. 108543

Author(s):

Zu'an Ding ◽

Zhaojun Yang ◽

Chuanhai Chen ◽

Weizheng Chen ◽

Hu Chen ◽

...

Keyword(s):

Piezoelectric Actuator ◽

Control Strategy ◽

Sliding Mode ◽

Dynamic Matrix Control ◽

Measuring Device ◽

Dynamic Matrix ◽

Precision Measuring ◽

Matrix Control

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TREE DIAMETER GROWTH FOLLOWING SILVICULTURAL TREATMENTS IN A SEMI-DECIDUOUS SECONDARY FOREST IN CENTRAL BRAZIL

CERNE ◽

10.1590/01047760201521011204 ◽

2015 ◽

Vol 21 (1) ◽

pp. 117-123 ◽

Cited By ~ 6

Author(s):

Fábio Venturoli ◽

Augusto César Franco ◽

Christopher William Fagg

Keyword(s):

Radial Growth ◽

Deciduous Forest ◽

Secondary Forest ◽

Basal Area ◽

Diameter Growth ◽

Annual Increment ◽

Tree Diameter ◽

Central Brazil ◽

Silvicultural Treatments ◽

Timber Market

In the Cerrado biome of Brazil, savannas and dry forests are intimately linked and form mosaics. These forests are composed of species of high commercial value, well accepted in the timber market, which causes intensive deforestation on the remaining vegetation. Thus, the management of these forests is an important alternative to reduce deforestation in the remaining vegetation. The objective of this study was to analyze the response of tree species in relation to silvicultural treatments of competition and liana cutting in a semi-deciduous forest in Central Brazil. The results showed that community basal area increased 24% over 4.8 years and the median periodic annual increment in diameter was about 20% higher in plots with silvicultural treatments: 2.9 mm.yr-1 in the control compared to 3.2 mm.yr-1 to 3.6 mm.yr-1 between treatments. This study demonstrated that it is possible to increase the rates of radial growth through silvicultural techniques.

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Modelling of tree diameter growth using growth functions parameterised by least squares and Bayesian methods

Journal of Forest Science ◽

10.17221/66/2011-jfs ◽

2012 ◽

Vol 58 (No. 6) ◽

pp. 245-252 ◽

Cited By ~ 7

Author(s):

R. Sedmák ◽

L. Scheer

Keyword(s):

Least Squares ◽

Bayesian Methods ◽

A Priori ◽

Nonlinear Least Squares ◽

Yield Function ◽

Growth And Yield ◽

Diameter Growth ◽

Tree Diameter ◽

Growth Functions ◽

Future Growth

The purpose of this paper is to present a new growth and yield function (denoted as KM-function), which was empirically derived from the cumulative density function of the Kumaraswamy probability distribution. KM-function is theoretically well disposed for the prediction of future growth; however, the function also has other theoretical features that make it useful also for retrospective estimation of the past growth frequently used in biological analyses of growth in the initial life stages. In order to demonstrate the practical applicability of the KM-function for growth reconstruction, an investigation of the accuracy of five-year retrospective projections of the real tree diameters obtained by stem analyses of 35 beech trees was done. Bias and accuracy of the new function were compared with bias and accuracy of some well-known growth functions on the same database. Compared functions were parameterised in two ways: by the method of nonlinear least squares and Bayesian methods. Empirical validation of the KM-function confirmed its good theoretical properties when it was used for retrospective estimation of the tree diameter growth. The valuable knowledge of this research is also a finding that the incorporation of a great deal of a priori known facts about the growth of trees and stands in natural conditions of Slovakia into Bayesian parameter estimation led to a decrease in the bias and magnitude of reconstruction errors.  

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Online Real-Time Detection Scheme Research on Precision of Filter Rod Circumference

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.731.340 ◽

2015 ◽

Vol 731 ◽

pp. 340-344

Author(s):

Qian Ru Tian ◽

Bang Gui He ◽

Zhi Long Wang

Keyword(s):

Real Time ◽

High Precision ◽

High Speed ◽

Contour Detection ◽

Discrete Control ◽

Compact Structure ◽

Detection Scheme ◽

Forming Mechanism ◽

Precision Measuring ◽

Real Time Detection

Precision of filter rod circumference is an important performance index of the cigarette manufacturing. The forming mechanism of filter rod, equipment vibration and other interference factors all lead to fluctuations of precision of filter rod circumference which can affect the precision of the cigarette. The existing KDF2/3 filter rod making machine which has the characteristics of compact structure (small space dimension), high speed (300 m/min) and discrete control of precision of filter rod circumference is the core equipment of filter rod production. This paper puts forward four kinds of online real-time detection schemes on precision of filter rod circumference which are Aomeijia’s many groups of detectors scheme, Keyence’s contour detection scheme, high precision measuring diameter instrument detection scheme using multiple sets of KD series meter and the 360 degrees rotating survey meter. On the basis of extensive analysis and experimental validation, Aomeijia’s four-way diameter measuring instrument scheme is optimal. The scheme applies laser to non-contact high speed scan on key radial diameter size of filter rod which achieves 0.001mm high precision detection.

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