scholarly journals Modeling natural mortality for different plant densities in dendroenergetic trials

2021 ◽  
Vol 53 (2) ◽  
pp. 143-156
Author(s):  
Simon Sandoval ◽  
Eduardo Acuña ◽  
Jorge Cancino ◽  
Rafael Rubilar
Keyword(s):  
Difference Equations ◽  
Survival Probability ◽  
Stand Density ◽  
Growth Period ◽  
State Variables ◽  
Individual Tree ◽  
Mortality Models ◽  
Tree Models ◽  
The Difference ◽  
The Individual

Mortality was modelled for three species (Acacia melanoxylon, Eucalyptus camaldulensis, Eucalyptus nitens) at three plantation densities (5000, 7500, and 10000 trees ha-1) in an trial of biomass production for purposes of dendroenergetic. One modelling based on individual tree level and two mortality modelling alternatives were evaluated: four survival probability equations and eight difference equations. The individual tree survival modelling considered a logistic model, is a linear combination of variables to individual tree at current time  and the previous time as estimator, being the main variables the variation of the competition index and the variation of basal area growth between the current growth period and the previous growth period. The survival probability alternative used state variables of the stand (age, dominant height, average square diameter) as predictors, whereas the difference equations were adjusted according to age-based changes only. The models to stand levels showed better result than individual tree models, and in general, the mortality models based on difference equations presented better indicators of precision and parsimony. The rate of relative mortality was constant, i.e., (dN/dE)/N, and varied between species, revealing greater mortality, consecutively, in E. nitens, A. melanoxylon, and E. camaldulensis. Although mortality tended to be higher at greater plantation densities, stand density did not significantly affect the parameters of the adjusted models. Highlights The mortality stand level models showed better results than the individual tree models for dendroenergetic crops, and in general, the mortality models based on difference equations presented better precision indicators and parsimony. The survival probability alternative involved state variables of the stand like age, dominant height, and average square diameter as predictors, while the difference equations were fitted according to age-based changes only. Mortality tended to be higher at greater plantation densities, however stand density did not significantly affect the parameters of the mortality equations.

Performance and comparison of stand growth models based on individual tree and diameter-class growth

1979 ◽  
Vol 9 (2) ◽  
pp. 231-244 ◽  
Author(s):  
Alan R. Ek ◽  
Robert A. Monserud
Keyword(s):  
Growth Model ◽  
Growth Models ◽  
Stand Density ◽  
Diameter Class ◽  
Tree Model ◽  
Individual Tree ◽  
Clear Cut ◽  
Individual Tree Model ◽  
The Individual ◽  
Stand Conditions

A distance-dependent individual tree based growth model (FOREST) was compared with a diameter-class growth model (SHAF) for describing changes in stand density and structure. Projections of Lake States' northern hardwood stand development were made by each model for 5–26 years over a range of stand conditions and harvest treatments. Results from numerous performance tests and comparisons of actual and predicted diameter distributions, basal areas, and numbers of trees, indicate the individual tree model was considerably more sensitive to harvest treatments and reproduction response than the diameter-class model. Conversely, the latter was much less expensive to operate. Prediction of species and individual tree growth with the individual tree model appeared to provide sensitivity nearly equal to that observed for predictions of the stand as a whole. Long-term projections (120 years) for reserve (no cut) and clear-cut stand conditions further suggest the potential and limitations of the models for management analyses.

scholarly journals The Effect of Tree Crown Allometry on Community Dynamics in Mixed-Species Stands versus Monocultures. A Review and Perspectives for Modeling and Silvicultural Regulation

Forests ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 810 ◽  
Author(s):  
Hans Pretzsch
Keyword(s):  
Community Dynamics ◽  
Stand Density ◽  
Tree Level ◽  
Mixed Species ◽  
Individual Tree ◽  
Tree Allometry ◽  
Management Concepts ◽  
Realistic Representation ◽  
The Individual ◽  
Species Specific

Many recent studies have shown that the structure, density, and productivity of mixed-species stands can differ from the weighted mean of monospecific stands of the respective species. The tree and stand properties emerging by inter-specific neighborhood should be considered in models for understanding and practical management. A promising approach for this is a more realistic representation of the individual tree allometry in models and management concepts, as tree allometry determines many structural and functional aspects at the tree and stand level. Therefore, this paper is focused on the crown allometry in mixed and mono-specific stands. Firstly, we review species-specific differences in the crown allometry in monospecific stands. Secondly, we show how species-specific differences and complementarities in crown allometry can emerge in mixed-species stands. Thirdly, the consequences of allometric complementarity for the canopy packing density will be analyzed. Fourthly, we trace the crown allometry from the tree level to the stand density and show the relevance for the self-thinning in mixed versus monospecific stands. Fifth, the consequence of the findings for modeling and regulating tree and stand growth will be discussed. The review deals mainly with widespread even-aged, mono-layered stands, but the main results apply for more heterogeneous stands analogously.

Empirical Study On Attributes Leading To Satisfaction Among Bank Customer

2019 ◽  
Vol 118 (7) ◽  
pp. 101-110
Author(s):  
Ms.U.Sakthi Veeralakshmi ◽  
Dr.G. Venkatesan
Keyword(s):  
Service Quality ◽  
Behavioral Intention ◽  
Banking Sector ◽  
Positive Impact ◽  
Quality Performance ◽  
Public And Private ◽  
The Difference ◽  
The Individual ◽  
Private Banking ◽  
Service Gap

This research aims at measuring the service quality in public and private banking sector and identifying its relationship to customer satisfaction and behavioral intention. The study was conducted among 500 bank customers by using revised SERVQUAL instrument with 26 items. Behavioral intention of the customers was measured by using the behavioral intention battery. The researcher has used a seven point likert scaling to measure the expected and perceived service quality (performance) and the behavioral intention of the customer. The instrument was selected as the most reliable device to measure the difference-score conceptualization. It is used to evaluate service gap between expectation and perception of service quality. Modifications are made on the SERVQUAL instrument to make it specific to the Banking sector. Questions were added to the instrument like Seating space for waiting (Tangibility), Parking space in the Bank (Tangibility), Variety of products / schemes available (Tangibility), Banks sincere steps to handling Grievances of the customers (Responsiveness). The findings of the study revealed that the customer’s perception (performance) is lower than expectation of the service quality rendered by banks. Responsiveness and Assurance SQ dimensions were the most important dimensions in service quality scored less SQ gap. The study concluded that the individual service quality dimensions have a positive impact on Overall Satisfaction.

Données LiDAR aériennes: pertinence de l'interprétation visuelle pour la foresterie

2017 ◽  
Vol 168 (3) ◽  
pp. 127-133
Author(s):  
Matthew Parkan
Keyword(s):  
Cross Sections ◽  
Forest Edge ◽  
Airborne Lidar ◽  
Visual Interpretation ◽  
Individual Tree ◽  
Small Areas ◽  
Interactive 3D ◽  
The Individual ◽  
Airborne Lidar Data ◽  
Stem Position

Airborne LiDAR data: relevance of visual interpretation for forestry Airborne LiDAR surveys are particularly well adapted to map, study and manage large forest extents. Products derived from this technology are increasingly used by managers to establish a general diagnosis of the condition of forests. Less common is the use of these products to conduct detailed analyses on small areas; for example creating detailed reference maps like inventories or timber marking to support field operations. In this context, the use of direct visual interpretation is interesting, because it is much easier to implement than automatic algorithms and allows a quick and reliable identification of zonal (e.g. forest edge, deciduous/persistent ratio), structural (stratification) and point (e.g. tree/stem position and height) features. This article examines three important points which determine the relevance of visual interpretation: acquisition parameters, interactive representation and identification of forest characteristics. It is shown that the use of thematic color maps within interactive 3D point cloud and/or cross-sections makes it possible to establish (for all strata) detailed and accurate maps of a parcel at the individual tree scale.

THE SUBJECT FIELD OF INSTITUTIONAL EDUCATION: THE SENSE AND PROSPECTS OF DEVELOPMENT IN UKRAINE

2020 ◽  
pp. 25-38
Author(s):  
Irina Mordous
Keyword(s):  
Decisive Role ◽  
Subject Field ◽  
National Education ◽  
Progressive Development ◽  
Separate Area ◽  
Economic Transformations ◽  
The Difference ◽  
The Individual ◽  
Political Economic

The development of modern civilization attests to its decisive role in the progressive development of institutions. They identified the difference between Western civilization and the rest of the world. Confirmation of the institutional advantages of the West was its early industrialization. The genesis and formation of institutionalism in its ideological and conceptualmethodological orientation occurs as a process alternative to neoclassic in the context of world heterodoxia, which quickly spread in social science. Highlighting institutional education as a separate area of sociocultural activity is determined by the factor of differentiation of institutional theory as a whole. A feature of institutional education is its orientation toward the individual and his/her transformation into a personality. The content of institutional education is revealed through the analysis of the institution, which includes a set of established customs, traditions, ways of thinking, behavioral stereotypes of individuals and social groups. The dynamics of socio-political, economic transformations in Ukraine requires a review of the foundations of national education and determination of the prospects for its development in the 21st century in the context of institutionalism.

Quantitative indicators of air traffic controllers’ attitude to the danger of errors

2020 ◽  
pp. 68-78
Author(s):  
O. M. Reva ◽  
V. V. Kamyshin ◽  
S. P. Borsuk ◽  
V. A. Shulhin ◽  
A. V. Nevynitsyn
Keyword(s):  
Human Factor ◽  
Differential Method ◽  
Air Traffic ◽  
Professional Activity ◽  
Aviation Accidents ◽  
Air Traffic Controllers ◽  
The Difference ◽  
Level Of Significance ◽  
The Individual ◽  
High Level

The negative and persistent impact of the human factor on the statistics of aviation accidents and serious incidents makes proactive studies of the attitude of “front line” aviation operators (air traffic controllers, flight crewmembers) to dangerous actions or professional conditions as a key component of the current paradigm of ICAO safety concept. This “attitude” is determined through the indicators of the influence of the human factor on decision-making, which also include the systems of preferences of air traffic controllers on the indicators and characteristics of professional activity, illustrating both the individual perception of potential risks and dangers, and the peculiarities of generalized group thinking that have developed in a particular society. Preference systems are an ordered (ranked) series of n = 21 errors: from the most dangerous to the least dangerous and characterize only the danger preference of one error over another. The degree of this preference is determined only by the difference in the ranks of the errors and does not answer the question of how much time one error is more dangerous in relation to another. The differential method for identifying the comparative danger of errors, as well as the multistep technology for identifying and filtering out marginal opinions were applied. From the initial sample of m = 37 professional air traffic controllers, two subgroups mB=20 and mG=7 people were identified with statisti-cally significant at a high level of significance within the group consistency of opinions a = 1%. Nonpara-metric optimization of the corresponding group preference systems resulted in Kemeny’s medians, in which the related (middle) ranks were missing. Based on these medians, weighted coefficients of error hazards were determined by the mathematical prioritization method. It is substantiated that with the ac-cepted accuracy of calculations, the results obtained at the second iteration of this method are more ac-ceptable. The values of the error hazard coefficients, together with their ranks established in the preference systems, allow a more complete quantitative and qualitative analysis of the attitude of both individual air traffic controllers and their professional groups to hazardous actions or conditions.

Quality-of-Life Measurement in Advanced Cancer: Assessing the Individual

1999 ◽  
Vol 17 (11) ◽  
pp. 3603-3611 ◽  
Author(s):  
Dympna Waldron ◽  
Ciaran A. O'Boyle ◽  
Michael Kearney ◽  
Michael Moriarty ◽  
Desmond Carney
Keyword(s):  
Quality Of Life ◽  
Advanced Cancer ◽  
Internal Validity ◽  
Semistructured Interview ◽  
Incurable Cancer ◽  
Life Measurement ◽  
The Difference ◽  
The Individual ◽  
Very High

PURPOSE: Despite the increasing importance of assessing quality of life (QoL) in patients with advanced cancer, relatively little is known about individual patient's perceptions of the issues contributing to their QoL. The Schedule for the Evaluation of Individual Quality of Life (SEIQoL) and the shorter SEIQoL–Direct Weighting (SEIQoL-DW) assess individualized QoL using a semistructured interview technique. Here we report findings from the first administration of the SEIQoL and SEIQoL-DW to patients with advanced incurable cancer. PATIENTS AND METHODS: QoL was assessed on a single occasion using the SEIQoL and SEIQoL-DW in 80 patients with advanced incurable cancer. RESULTS: All patients were able to complete the SEIQoL-DW, and 78% completed the SEIQoL. Of a possible score of 100, the median QoL global score was as follows: SEIQoL, 61 (range, 24 to 94); SEIQoL-DW, 60.5 (range, 6 to 95). Psychometric data for SEIQoL indicated very high levels of internal consistency (median r = .90) and internal validity (median R2 = 0.88). Patients' judgments of their QoL were unique to the individual. Family concerns were almost universally rated as more important than health, the difference being significant when measured using the SEIQoL-DW (P = .002). CONCLUSION: Patients with advanced incurable cancer were very good judges of their QoL, and many patients rated their QoL as good. Judgments were highly individual, with very high levels of consistency and validity. The primacy given to health in many QoL questionnaires may be questioned in this population. The implications of these findings are discussed with regard to clinical assessment and advance directives.

scholarly journals Nondestructive Detection of the Gel State of Preserved Eggs Based on Dielectric Impedance

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 394
Author(s):  
Cheng-Han Li ◽  
Chun-Hung Hsieh ◽  
Cheng-Chu Hung ◽  
Ching-Wei Cheng
Keyword(s):  
Decay Rate ◽  
Mechanical Vibration ◽  
Scientific Basis ◽  
Nondestructive Method ◽  
Inspection System ◽  
Nyquist Diagram ◽  
Detection Technology ◽  
The Difference ◽  
The Individual

After completing the production of preserved eggs, traditionally, the degree of gelling is judged by allowing workers to tap the preserved eggs with their fingers and sense the resulting oscillations. The amount of oscillation is used for the quality classification. This traditional method produces varying results owing to the differences in the sensitivity of the individual workers, who are not objective. In this study, dielectric detection technology was used to classify the preserved eggs nondestructively. The impedance in the frequency range of 2–300 kHz was resolved into resistance and reactance, and was plotted on a Nyquist diagram. Next, the diagram curve was fitted in order to obtain the equivalent circuit, and the difference in the compositions of the equivalent circuits corresponding to gelled and non-gelled preserved eggs was analyzed. A preserved egg can be considered an RLC series circuit, and its decay rate is consistent with the decay rate given by mechanical vibration theory. The Nyquist diagrams for the resistance and reactance of preserved eggs clearly showed that the resistance and reactance of gelled and non-gelled eggs were quite different, and the classification of the eggs was performed using Bayesian network (BN). The results showed that a BN classifier with two variables, i.e., resistance and reactance, can be used to classify preserved eggs as gelled or non-gelled, with an accuracy of 81.0% and a kappa value of 0.62. Thus, a BN classifier based on resistance and reactance demonstrates the ability to classify the quality of preserved egg gel. This research provides a nondestructive method for the inspection of the quality of preserved egg gel, and provides a theoretical basis for the development of an automated preserved egg inspection system that can be used as the scientific basis for the determination of the quality of preserved eggs.

scholarly journals Crown Structure Explains the Discrepancy in Leaf Phenology Metrics Derived from Ground- and UAV-Based Observations in a Japanese Cool Temperate Deciduous Forest

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 425
Author(s):  
Noviana Budianti ◽  
Hiromi Mizunaga ◽  
Atsuhiro Iio
Keyword(s):  
Deciduous Forest ◽  
Leaf Expansion ◽  
Image Resolution ◽  
Leaf Phenology ◽  
Visual Interpretation ◽  
Temperate Deciduous Forest ◽  
Individual Tree ◽  
Crown Structure ◽  
Uav Images ◽  
The Individual

Unmanned aerial vehicles (UAV) provide a new platform for monitoring crown-level leaf phenology due to the ability to cover a vast area while offering branch-level image resolution. However, below-crown vegetation, e.g., understory vegetation, subcanopy trees, and the branches of neighboring trees, along with the multi-layered structure of the target crown may significantly reduce the accuracy of UAV-based estimates of crown leaf phenology. To test this hypothesis, we compared UAV-derived crown leaf phenology results against those based on ground observations at the individual tree scale for 19 deciduous broad-leaved species (55 individuals in total) characterized by different crown structures. The mean crown-level green chromatic coordinate derived from UAV images poorly explained inter- and intra-species variations in spring leaf phenology, most probably due to the consistently early leaf emergence in the below-crown vegetation. The start dates for leaf expansion and end dates for leaf falling could be estimated with an accuracy of <1-week when the influence of below-crown vegetation was removed from the UAV images through visual interpretation. However, a large discrepancy between the phenological metrics derived from UAV images and ground observations was still found for the end date of leaf expansion (EOE) and start date of leaf falling (SOF). Bayesian modeling revealed that the discrepancy for EOE increased as crown length and volume increased. The crown structure was not found to contribute to the discrepancy in SOF value. Our study provides evidence that crown structure is a pivotal factor to consider when using UAV photography to reliably estimate crown leaf phenology at the individual tree-scale.

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