MétaCan
Menu
← Back to cohort
Record W2582474650 · doi:10.1139/cjfr-2016-0135

Integrated system of equations for estimating stem volume, density, and biomass for Australian redcedar (<i>Toona ciliata</i>) plantations

2017· article· en· W2582474650 on OpenAlexvenueno aff
Natalino Calegário, Timothy G. Grégoire, Tatiane Antunes da Silva, Mário Tomazello Filho, Joyce A. Alves

Bibliographic record

VenueCanadian Journal of Forest Research · 2017
Typearticle
Languageen
FieldEnvironmental Science
TopicForest ecology and management
Canadian institutionsnot available
FundersConselho Nacional de Desenvolvimento Científico e TecnológicoFundação de Amparo à Pesquisa do Estado de Minas GeraisInnovative Research Group Project of the National Natural Science Foundation of China
KeywordsPithBotanyMathematicsBark (sound)RADIUSDiameter at breast heightHorticultureForestryBiologyGeography

Abstract

fetched live from OpenAlex

A system of equations is proposed to assess the stem wood density variation of Toona ciliata M. Roem. growing in Brazilian plantations. As a taper function, a third-degree polynomial was fitted and the stem radius squared (r2), the dependent variable, was estimated as a function of diameter at breast height (dbh), total height (ht), and radius (r) at height (h). A nonlinear function was fitted to estimate wood density variation, having as the independent variable the ratio of r to h. The stem mass was estimated by integrating the product of stem volume and wood density. Stem measurements from a group of 72 trees of T. ciliata were used to fit the taper equation. A group of six trees was selected and a wood density database was created using X-ray technology. Both the taper and the nonlinear functions performed well in estimating the radius and the wood density. The within-tree wood density systematically increased from pith to bark and from the base to the top of the tree. With the density varying from base to top, the estimated mass of the stem, compared with the mass estimated using wood density value at dbh, had a bias of 4.2%. When the density variations from base to top and from pith to bark of the tree were considered, the estimated mass had a bias of 1.5%.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.003
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Simulation or modeling · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: none
Teacher disagreement score0.034
Threshold uncertainty score0.068

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.003
Meta-epidemiology (narrow)0.0010.001
Meta-epidemiology (broad)0.0010.001
Bibliometrics0.0020.001
Science and technology studies0.0010.000
Scholarly communication0.0010.001
Open science0.0010.001
Research integrity0.0010.001
Insufficient payload (model declined to judge)0.0030.001

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.079
GPT teacher head0.330
Teacher spread0.251 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designSimulation or modeling
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations8
Published2017
Admission routes1
Has abstractyes

Explore more

Same venueCanadian Journal of Forest Research→Same topicForest ecology and management→French-language works237,207→