Simultaneous Linear Prediction and Construction of Volume Tables

1973 ◽  
Vol 3 (3) ◽  
pp. 418-423
Author(s):  
J. Bélanger ◽  
R. Cléroux

In this paper a technique is proposed which finds a unique linear predictor which is used to construct volume tables for different tree species, when it is multiplied by proper scaling factors. This technique uses the fact that one species can give information about some other. This information can be used in future studies where data are not available on all the species considered.

IAWA Journal ◽  
2008 ◽  
Vol 29 (2) ◽  
pp. 189-207 ◽  
Author(s):  
Claudio S. Lisi ◽  
Mário Tomazello Fo ◽  
Paulo C. Botosso ◽  
Fidel A. Roig ◽  
Vivian R.B. Maria ◽  
...  

Many tropical tree species produce growth rings in response to seasonal environmental factors that influence the activity of the vascular cambium. We applied the following methods to analyze the annual nature of treering formation of 24 tree species from a seasonal semi-deciduous forest of southeast Brazil: describing wood anatomy and phenology, counting tree rings after cambium markings, and using permanent dendrometer bands. After 7 years of systematic observations and measurements, we found the following: the trees lost their leaves during the dry season and grew new leaves at the end of the same season; trunk increment dynamics corresponded to seasonal changes in precipitation, with higher increment (active period) during the rainy season (October–April) and lower increment (dormant period) during the dry season (May–September); the number of tree rings formed after injuries to the cambium coincided with the number of years since the extraction of the wood samples. As a result of these observations, it was concluded that most study trees formed one growth ring per year. This suggests that tree species from the seasonal semi-deciduous forests of Brazil have an annual cycle of wood formation. Therefore, these trees have potential for use in future studies of tree age and radial growth rates, as well as to infer ecological and regional climatic conditions. These future studies can provide important information for the management and conservation of these endangered forests.


2007 ◽  
Vol 32 (1) ◽  
pp. 6-23 ◽  
Author(s):  
Shelby J. Haberman ◽  
Jiahe Qian

Statistical prediction problems often involve both a direct estimate of a true score and covariates of this true score. Given the criterion of mean squared error, this study determines the best linear predictor of the true score given the direct estimate and the covariates. Results yield an extension of Kelley’s formula for estimation of the true score to cases in which covariates are present. The best linear predictor is a weighted average of the direct estimate and of the linear regression of the direct estimate onto the covariates. The weights depend on the reliability of the direct estimate and on the multiple correlation of the true score with the covariates. One application of the best linear predictor is to use essay features provided by computer analysis and an observed holistic score of an essay provided by a human rater to approximate the true score corresponding to the holistic score.


Author(s):  
Thi-Mai-Phuong Dao

A fuzzy logic – based controller has been considered to be a feasible and effective control strategy for a numerous number of complex control problems. To design such an effective fuzzy logic controller, it is necessary to determine proper scaling factors which significantly affect the control quality of the system. This study concentrates on applying well-known bio-inspired optimization methods, i.e. PSO, GA and DE, to deal with this determination. A typical PD-type fuzzy logic architecture is chosen to be a traditionally intelligent controller. Then, the bio-inspired optimization methods will be applied for such a fuzzy logic controller to optimally determine its three scaling factors. The simulation results provided for the load – frequency control issue of a two-area interconnected hydropower system verifies the applicability of the proposed control strategy. Comparative simulations are also to decide which is the best choice of the bio-inspired optimization methods in the determination of significant scaling factors regarding the PD-type fuzzy logic controller.


1983 ◽  
Vol 91 ◽  
pp. 173-184 ◽  
Author(s):  
Sheu-San Lee

We shall discuss in this paper some problems in non-linear prediction theory. An Ornstein-Uhlenbeck process {U(t)} is taken to be a basic process, and we shall deal with stochastic processes X(t) that are transformed by functions f satisfying certain condition. Actually, observed processes are expressed in the form X(t) = f(U(t)). Our main problem is to obtain the best non-linear predictor X̂(t, τ) for X(t + τ), τ > 0, assuming that X(s), s ≤t, are observed. The predictor is therefore a non-linear functional of the values X(s), s ≤ t.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5736 ◽  
Author(s):  
Jiayi Feng ◽  
Kangning Zhao ◽  
Dong He ◽  
Suqin Fang ◽  
TienMing Lee ◽  
...  

Shade tolerance, the minimum light requirement for plant survival, is a key trait for understanding community assembly and forest dynamics. However, it is poorly defined for tree species to date. Current methods of measuring shade tolerance vary considerably in their performance. For instance, some measures of shade tolerance are unreliable except under some specific conditions. Therefore, it is necessary to compare the performance of these methods to provide guidance of choosing appropriate shade tolerance measures in future studies. We collected a large dataset of light traits and other life history traits for 137 understory wood species in a subtropical forest and tested the performance of five commonly used shade-tolerance indices. Results showed that all the shade-tolerance measures, except the low-light abundance index, performed poorly in distinguishing and ranking shade tolerance of the tested species. The shade tolerance quantified by the low-light abundance was consistent with empirical classification of shade-tolerance/intolerance groups and successional seral stages of species. Comparison of the shade tolerance between trees of different diameter at breast height (DBH) or height classes further confirmed the reliability of low-light abundance. We conclude that low-light abundance is the most objective and practical of the five most commonly-used methods for measuring and ranking shade tolerance of understory wood species in our study forest, and likely in other forests as well. The simplicity of the method should greatly facilitate the assessment of light niche differentiation between species and thus contribute to understanding coexistence of tree species in forests.


Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2185
Author(s):  
Aimé Lay-Ekuakille ◽  
Vito Telesca ◽  
Paolo Visconti ◽  
Nicola Ivan Giannoccaro

Rural pipelines dedicated to water distribution, that is, waterworks, are essential for agriculture, notably plantations and greenhouse cultivation. Water is a primary resource for agriculture, and its optimized management is a key aspect. Saving water dispersion is not only an economic problem but also an environmental one. Spectral estimation of leakage is based on processing signals captured from sensors and/or transducers generally mounted on pipelines. There are different techniques capable of processing signals and displaying the actual position of leaks. Not all algorithms are suitable for all signals. That means, for pipelines located underground, for example, external vibrations affect the spectral response quality; then, depending on external vibrations/noises and flow velocity within pipeline, one should choose a suitable algorithm that fits better with the expected results in terms of leak position on the pipeline and expected time for localizing the leak. This paper presents findings related to the application of a decimated linear prediction (DLP) algorithm for agriculture and rural environments. In a certain manner, the application also detects the hydrodynamics of the water transportation. A general statement on the issue, DLP illustration, a real application and results are also included.


Trees ◽  
2020 ◽  
Vol 34 (6) ◽  
pp. 1453-1466
Author(s):  
T. Asbeck ◽  
M. Basile ◽  
J. Stitt ◽  
J. Bauhus ◽  
I. Storch ◽  
...  

Abstract Key message Drivers of the abundance and richness of tree-related microhabitats are similar in mountain forests of Europe and North America and their occurrence may be explained by tree functional groups. Abstract A common approach to support forest-dwelling species in managed forests is to preserve valuable habitat trees. To assess the quality of habitat trees, a hierarchical typology of tree-related microhabitats (TreMs) is applied in the European context for inventory standardization. The first aim of this study was to evaluate whether it is possible to use this hierarchical typology as a standard protocol regardless of location, which is important for potentially standardizing future studies of TreMs, by testing whether the typology could be applied to the western North American mountain forests of Idaho. The second aim of the study was to analyse drivers that influence TreMs in forests of the region. Thirdly, we assessed whether the occurrence of TreMs could be explained by functional groups of trees across the western mountain forests of Idaho and Central European mountain forests, using TreM inventory data previously collected in the Black Forest, Germany. Abundance and richness of TreMs per tree were analyzed as a function of tree species, live status (dead vs. live trees), diameter at breast height (DBH), and site factors (latitude and altitude). Our results show that the TreM typology could be applied with slight modifications in the forests of Idaho. The abundance and richness of TreMs per tree increased with DBH. Snags offered more TreMs per tree than live trees. We were able to group tree species from the two continents in functional groups that were related to the occurrence of certain TreMs. Tree functional groups offer an opportunity to predict the role of certain tree species for habitat provision through TreMs. Combinations of trees from different functional groups could be used to optimize provisioning of TreMs within forest stands.


Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1266
Author(s):  
Anastasia Christopoulou ◽  
Barbara Gmińska-Nowak ◽  
Yasemin Özarslan ◽  
Tomasz Ważny

The current study presents the results of the first dendrochronological survey performed over the East Aegean island of Symi. Research Highlights: Dendrochronological research of the East Aegean region is of paramount importance since dendrochronological data from the region, and especially the islands, are still limited. Background and Objectives: The main aim of the study is to explore the dendrochronological potential of the island, focusing on the dating of historical wood and buildings as well as dendroprovenancing. Materials and Methods: A total of 57 wood samples were collected from historical timber from windmills and architectural elements, including doors and warehouse planks, while 68 cores were collected from the three dominant tree species of the island—Cupressus sempervirens, Pinus brutia, and Quercus ithaburensis subsp. macrolepis—in an attempt to develop local reference chronologies that could be useful in dating historical timber Results: Of the historical timber, at least nine different species have been detected, with conifers representing the majority of the collected material. In total, 56% of the dendroarchaeological samples, belonging to four different species, were dated absolutely. According to cross-dating and dendroprovenancing results, Pinus nigra, Cedrus sp., and Quercus sp. represent timber imported from present-day Turkey while the fir samples collected from the windmills originate from Central Europe. The use of local timber is also highly probable although it could not be confirmed by the reference chronologies developed for the three dominant tree species of the island. Conclusions: The results of the study reveal the dendrochronological potential of the island from both dendroarchaeological and dendroecological perspectives. The finding that most of the wood was imported mainly from Turkey highlights the importance of timber trade with the Turkish mainland during the mid-18th and 19th centuries. Chronologies developed from living trees could be used in future studies for dating historical material while further research would increase our understanding of past timber trade and the island’s history.


2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Carlos Lastre-Domínguez ◽  
Yuriy S. Shmaliy ◽  
Oscar Ibarra-Manzano ◽  
Jorge Munoz-Minjares ◽  
Luis J. Morales-Mendoza

Methods of the electrocardiography (ECG) signal features extraction are required to detect heart abnormalities and different kinds of diseases. However, different artefacts and measurement noise often hinder providing accurate features extraction. One of the standard techniques developed for ECG signals employs linear prediction. Referring to the fact that prediction is not required for ECG signal processing, smoothing can be more efficient. In this paper, we employ the p-shift unbiased finite impulse response (UFIR) filter, which becomes smooth by p<0. We develop this filter to have an adaptive averaging horizon: optimal for slow ECG behaviours and minimal for fast excursions. It is shown that the adaptive UFIR algorithm developed in such a way provides better denoising and suboptimal features extraction in terms of the output signal-noise ratio (SNR). The algorithm is developed to detect durations and amplitudes of the P-wave, QRS-complex, and T-wave in the standard ECG signal map. Better performance of the algorithm designed is demonstrated in a comparison with the standard linear predictor, UFIR filter, and UFIR predictive filter based on real ECG data associated with normal heartbeats.


Author(s):  
V. Kriho ◽  
H.-Y. Yang ◽  
C.-M. Lue ◽  
N. Lieska ◽  
G. D. Pappas

Radial glia have been classically defined as those early glial cells that radially span their thin processes from the ventricular to the pial surfaces in the developing central nervous system. These radial glia constitute a transient cell population, disappearing, for the most part, by the end of the period of neuronal migration. Traditionally, it has been difficult to definitively identify these cells because the principal criteria available were morphologic only.Using immunofluorescence microscopy, we have previously defined a phenotype for radial glia in rat spinal cord based upon the sequential expression of vimentin, glial fibrillary acidic protein and an intermediate filament-associated protein, IFAP-70/280kD. We report here the application of another intermediate filament-associated protein, IFAP-300kD, originally identified in BHK-21 cells, to the immunofluorescence study of radial glia in the developing rat spinal cord.Results showed that IFAP-300kD appeared very early in rat spinal cord development. In fact by embryonic day 13, IFAP-300kD immunoreactivity was already at its peak and was observed in most of the radial glia which span the spinal cord from the ventricular to the subpial surfaces (Fig. 1). Interestingly, from this time, IFAP-300kD immunoreactivity diminished rapidly in a dorsal to ventral manner, so that by embryonic day 16 it was detectable only in the maturing macroglial cells in the marginal zone of the spinal cord and the dorsal median septum (Fig. 2). By birth, the spinal cord was essentially immuno-negative for this IFAP. Thus, IFAP-300kD appears to be another differentiation marker available for future studies of gliogenesis, especially for the early stages of radial glia differentiation.


Sign in / Sign up

Export Citation Format

Share Document