Early volume formulas, taper, implicit volume ratio, and auxiliary information: A new system of volume equations invariant to silvicultural practices, site, and genetic pedigree

2020 ◽  
Vol 475 ◽  
pp. 118412
Author(s):  
John Paul McTague ◽  
Henrique Ferraço Scolforo ◽  
José Roberto S. Scolforo
Keyword(s):  
Auxiliary Information ◽  
Volume Ratio ◽  
Silvicultural Practices ◽  
Volume Equations ◽  
New System

Compatible Tree Volume and Taper Functions for Pitch Pine

1985 ◽  
Vol 2 (1) ◽  
pp. 14-16 ◽  
Author(s):  
Edwin J. Green ◽  
David D. Reed
Keyword(s):  
Volume Ratio ◽  
Stem Diameter ◽  
Individual Tree ◽  
Pitch Pine ◽  
Volume Equations

Abstract Individual tree taper, volume ratio, and total volume equations are presented for pitch pine. The volume ratio equations may be used to determine merchantable volume to any height or upper stem diameter. The equations are compatible and are based on a recommended taper curve. Examples of how to employ the equations are presented. North J. Appl. For. 2:14-16, Mar. 1985.

scholarly journals Compatible Taper and Stem Volume Equations for Five Pine Species in Mixed-Species Forests in Mexico

2019 ◽  
Vol 65 (5) ◽  
pp. 602-613
Author(s):  
Gerónimo Quiñonez-Barraza ◽  
Dehai Zhao ◽  
Héctor Manuel De los Santos-Posadas
Keyword(s):  
Volume Ratio ◽  
Stem Volume ◽  
Volume Data ◽  
Stem Height ◽  
White Pine ◽  
Mixed Species ◽  
Cumulative Volume ◽  
Volume Equations ◽  
Better Than ◽  
Pine Species

Abstract Ten systems of compatible taper and outside-bark volume equations derived from upper-height-based volume ratio equations were compared with a used segmented-stem system of compatible taper and volume equations. All the systems were simultaneously fitted to cumulative volume data and taper data for Arizona pine, Aztec pine, Durango pine, Mexican white pine, and Smooth-leaved pine species in naturally regenerated mixed-species forests in Mexico. The systems derived from volume ratio equations performed better than the segmented-stem system for most species. The resultant top systems might be easier to implement than the segmented-stem system for predicting upper-stem height, upper-stem diameter, merchantable volume, and total stem volume for considered species.

scholarly journals Generalized stem taper and tree volume equations applied to eucalyptus of varying genetics in Brazil

2019 ◽  
Vol 49 (5) ◽  
pp. 447-462 ◽  
Author(s):  
Henrique Ferraco Scolforo ◽  
John Paul McTague ◽  
Harold Burkhart ◽  
Joseph Roise ◽  
Rafaela Lorenzato Carneiro ◽  
...  
Keyword(s):  
Model Performance ◽  
Volume Ratio ◽  
Forest Products ◽  
Single Product ◽  
Stem Taper ◽  
Volume Modeling ◽  
Volume Equation ◽  
Predictive Validation ◽  
Total Tree ◽  
Volume Equations

Lack of generalized equations has prevailed in Brazil, because it is assumed that localized or climate-specific equations are needed. This study aimed to develop generalized stem taper and volume equations applicable to 11 eucalyptus clones and evaluate if climate variation impacts the accuracy of the estimates. A total of 693 trees evenly distributed across 11 clones at 21 sites were used for model fittings and predictive validation. The penalized mixed spline (PMS) approach was developed for predicting stem taper and volume along the stem profile. The Schumacher and Hall (1933) equation was used to predict total tree volume, while volume ratio equations were applied to predict merchantable volume. For every fitted equation, an annual climatic variable was included to assess the improvement in model performance. The overall results highlighted that climatic variation does not need to be accounted for in stem taper and volume modeling. All of the equations displayed desirable accuracy, but the generalized PMS equation may be preferred when the forestry enterprise looks to furnish a range of multiple forest products. The generalized total tree volume equation, combined with the ratio equations, is highly recommended when the forestry enterprise produces a single product.

scholarly journals Compatible Taper and Volume Systems Based on Volume Ratio Models for Four Pine Species in Oaxaca Mexico

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 145
Author(s):  
Albert Castillo-López ◽  
Gerónimo Quiñonez-Barraza ◽  
Ulises Diéguez-Aranda ◽  
José Javier Corral-Rivas
Keyword(s):  
Sustainable Forest Management ◽  
Essential Element ◽  
Volume Ratio ◽  
Stem Volume ◽  
Mixed Species ◽  
Commercial Species ◽  
Pinus Pseudostrobus ◽  
Total Tree ◽  
Volume Equations ◽  
Pine Species

Estimating tree volume components is an essential element in sustainable forest management. Compatible taper and merchantable outside-bark volume systems based on volume ratio models were globally fitted to four pine species (reduced models) with the aim to select the best reduced model and to fit it with dummy variables and additive effects using Pinus pseudostrobus Lindl as a base species. The study was carried out in the northern mountains of Oaxaca, Mexico. To fit the taper, merchantable volume, stem volume, branch volume, and total tree volume (stem volume and branch volume) equations, a taper dataset of 222, 230, 245, and 333 trees of Pinus douglasiana Martínez (Pd), Pinus oaxacana Mirov (Po), Pinus patula Schltd (Pp), and Pinus pseudostrobus Lindl (Pps), respectively, was used. In general, the compatible systems explained more than 97% in the observed variability for the four studied components: outside-bark diameter (d), merchantable outside-bark volume (Vm), stem outside-bark volume (Vs), and total tree volume (Vt). Alternatively, more than 52% of the observed variability for branch volume (Vb) was also explained. The developed compatible systems based on volume ratio models are a simple and consistent alternative for estimating the outside-bark diameter and variable outside-bark volume, as well as the components of commercial species for uneven-age and mixed-species forests in Oaxaca, Mexico.

TEM observation of iron oxide pillars in montmorillonite

1990 ◽  
Vol 48 (4) ◽  
pp. 882-883
Author(s):  
H. Mori ◽  
Y. Murata ◽  
H. Yoneyama ◽  
H. Fujita
Keyword(s):  
Aqueous Solution ◽  
Iron Oxide ◽  
Fine Particles ◽  
Aqueous Suspension ◽  
Volume Ratio ◽  
Exchange Capacity ◽  
Nano Composites ◽  
Pillared Montmorillonite ◽  
Topographic Features ◽  
Transmission Electron

Recently, a new sort of nano-composites has been prepared by incorporating such fine particles as metal oxide microcrystallites and organic polymers into the interlayer space of montmorillonite. Owing to their extremely large specific surface area, the nano-composites are finding wide application[1∼3]. However, the topographic features of the microstructures have not been elucidated as yet In the present work, the microstructures of iron oxide-pillared montmorillonite have been investigated by high-resolution transmission electron microscopy.Iron oxide-pillared montmorillonite was prepared through the procedure essentially the same as that reported by Yamanaka et al. Firstly, 0.125 M aqueous solution of trinuclear acetato-hydroxo iron(III) nitrate, [Fe3(OCOCH3)7 OH.2H2O]NO3, was prepared and then the solution was mixed with an aqueous suspension of 1 wt% clay by continuously stirring at 308 K. The final volume ratio of the latter aqueous solution to the former was 0.4. The clay used was sodium montmorillonite (Kunimine Industrial Co.), having a cation exchange capacity of 100 mequiv/100g. The montmorillonite in the mixed suspension was then centrifuged, followed by washing with deionized water. The washed samples were spread on glass plates, air dried, and then annealed at 673 K for 72 ks in air. The resultant film products were approximately 20 μm in thickness and brown in color.

New System Targets Rotors for AF Ablation

2011 ◽  
Vol 9 (7) ◽  
pp. 20-21
Author(s):  
BRUCE JANCIN
Keyword(s):  
Af Ablation ◽  
New System

The Impact of Missing and Error-Prone Auxiliary Information on Sparse-Matrix Sub-Population Parameter Estimates

Methodology ◽  
2015 ◽  
Vol 11 (3) ◽  
pp. 89-99 ◽  
Author(s):  
Leslie Rutkowski ◽  
Yan Zhou
Keyword(s):  
Sparse Matrix ◽  
Small Body ◽  
Auxiliary Information ◽  
Poor Quality ◽  
Quality Data ◽  
Estimation Methods ◽  
Parameter Estimates ◽  
Population Parameter ◽  
Conditioning Model ◽  
The Impact

Abstract. Given a consistent interest in comparing achievement across sub-populations in international assessments such as TIMSS, PIRLS, and PISA, it is critical that sub-population achievement is estimated reliably and with sufficient precision. As such, we systematically examine the limitations to current estimation methods used by these programs. Using a simulation study along with empirical results from the 2007 cycle of TIMSS, we show that a combination of missing and misclassified data in the conditioning model induces biases in sub-population achievement estimates, the magnitude and degree to which can be readily explained by data quality. Importantly, estimated biases in sub-population achievement are limited to the conditioning variable with poor-quality data while other sub-population achievement estimates are unaffected. Findings are generally in line with theory on missing and error-prone covariates. The current research adds to a small body of literature that has noted some of the limitations to sub-population estimation.

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