scholarly journals Stacked-timber ratio and stem volume of horse chestnut trees within Kyiv City urban stands

2020 ◽  
Vol 11 (2) ◽  
pp. 32-39
Author(s):  
O. M. Lesnik
Keyword(s):  
Form Factor ◽  
Urban Environment ◽  
Urban Forest ◽  
Factor Model ◽  
Form Factors ◽  
Stem Volume ◽  
Horse Chestnut ◽  
Forest Stands ◽  
Growth Environment ◽  
Forest Mensuration

Urban forest are influenced by urban environment, what has a negative effect on the vital activities of the trees. Growth environment of trees on urban territories and in natural areas are completely different. Research data was collected in urban forest stands of Kyiv city during thinnings. Special methodological characteristics of the measuring of main biometrical tree parameters in urban area are explained in this work. Importantly, chestnut trees have morphological feature which stems are branching on the certain height leading to occurrence of the several main branches. Modelling tree stem volume, the most important pattern to find was a mathematical dependence of form factors on the main tree biometrical parameters. Basic descriptive statistics of chestnut trees parameters were estimated. It is defined that the percentage of trunk volume decreases with an increase of tree diameter and in trees over 60 cm can make up to 30% of the total tree volume. Carrying out a correlation analysis of model trees, it was examined that form factors of tree stems were highly linked to the branching height. Based on the statistical analysis it was estimated that developed mathematical model reflected empirical data adequately and could be validated according to the current forest mensuration accuracy requirements properly. Moreover, a bias of the developed form factor model examined using Student t-criteria is not significant. Respective information-support tables to estimate stem volume of chestnut trees were created based on the developed form factor model, harnessing the classical formula of forest mensuration. Given stem volume tables created considering physiological features of chestnut trees under urban environment conditions can be utilized by the organizations which manage forest stands and parks within settlements.

scholarly journals Developing local volume tables for three important tree species in Nawalparasi and Kapilvastu districts

2018 ◽  
pp. 84-91 ◽  
Author(s):  
H. L. Shrestha ◽  
M. R. Kafle ◽  
K. Khanal ◽  
R. A. Mandal ◽  
K. Khanal
Keyword(s):  
Form Factor ◽  
Cross Sections ◽  
Tree Species ◽  
Form Factors ◽  
Smooth Curve ◽  
Stem Volume ◽  
Destructive Sampling ◽  
Timber Volume ◽  
Local Volume ◽  
Standing Trees

The local volume tables of specific species are very important to estimate the timber volume of standing trees but precise site-specific volume tables are lacking for three important tree species, namely Dalbergia sissoo, Shorea robusta and Terminalia alata. Therefore, this study was carried out to develop local volume tables and determine the form factors of these species using destructive and non-destructive methods. Kapilvastu and Nawalparasi districts were selected for this study. Altogether, 188 vigorous trees were selected for measurement, out of which 156 (52 trees for each species) were from destructive sampling and 32 were standing trees. The data of destructive sampling trees of three species were used in developing the models for under bark timber volume up to 10 and 20 cm top diameters. Thirty two data (12 for S. robusta, 10 for T. alata and for D. sissoo each) of standing trees were used to validate the models of three species. A number of cross sections were made and actual volumes of stem, butt log, other sections and top portion were calculated using cylindrical, Newton’s, Smalian’s and cone formulae, respectively. The cylindrical volume was estimated based on diameter at breast height. The form factor was determined from the ratio of actual and cylindrical volumes. The diameter and height relationship was made and, based on this; the smooth curve was drawn to develop the local volume tables. The results showed that estimated form factor of 10 cm and 20 cm top diameter of selected species varied from 0.50 to 0.69. In addition, local volume tables are developed for stem volume based on diameter under bark. Banko JanakariA Journal of Forestry Information for Nepal Special Issue No. 4, 2018, Page: 84-91 

The influence of the nuclear and atomic form factors on the muon bremsstrahlung cross section

1968 ◽  
Vol 46 (10) ◽  
pp. S377-S380 ◽  
Author(s):  
A. A. Petrukhin ◽  
V. V. Shestakov
Keyword(s):  
Form Factor ◽  
Cross Section ◽  
Born Approximation ◽  
Form Factors ◽  
Experimental Results ◽  
Simple Analytical Expression ◽  
Nuclear Form Factor ◽  
The Cross ◽  
Atomic Electrons ◽  
Bremsstrahlung Process

The cross section for the muon bremsstrahlung process is calculated as a function of the nuclear form factor in the Born approximation following the Bethe and Heitler theory. The influence of the nuclear form factor is greater than that taken by Christy and Kusaka. The simple analytical expression for the effect of the screening of the atomic electrons is found. The influence of a decrease in the cross section upon the interpretation of some experimental results is estimated.

Helm model interpretation of 16O form factors: application to pion photoproduction and muon capture

1980 ◽  
Vol 58 (1) ◽  
pp. 48-62 ◽  
Author(s):  
R. D. Graves ◽  
B. A. Lamers ◽  
Anton Nagl ◽  
H. Überall ◽  
V. Devanathan ◽  
...  
Keyword(s):  
Form Factor ◽  
Electron Scattering ◽  
Form Factors ◽  
Muon Capture ◽  
Physical Parameters ◽  
Medium Energy ◽  
Model Interpretation ◽  
Charged Pions ◽  
Transition Densities ◽  
Energy Processes

The available experimental data for the form factors of the T = 1 levels in 16O, obtained from electron scattering at low (Darmstadt), medium (Tohoku), and high momentum transfer (Stanford), are interpreted by the generalized Helm model. This phenomenological model reduces the form factor description of each level to the listing of a few physical parameters, i.e., the radius and smearing width of the transition densities of charge (current) and magnetization, and their corresponding strength constants. Its parameters having been determined by the form factor fits, the model may then be used to predict the results of other medium energy processes; this is done here for the photoproduction of charged pions and for muon capture in16O.

scholarly journals Form Factor of Eucalyptus Saligna Species in a Commercial Forest Plantation

2021 ◽  
Author(s):  
N. Lara ◽  
M. Guallpa ◽  
F. Acosta ◽  
Á. Barahona
Keyword(s):  
Form Factor ◽  
Graphical Method ◽  
Form Factors ◽  
Coefficient Of Determination ◽  
Forest Plantation ◽  
Eucalyptus Saligna ◽  
Palabras Clave ◽  
Para Determinar ◽  
Commercial Forest ◽  
Volume Equations

The present investigation proposes to determine the form factor of the species Eucalyptus saligna in a commercial forest plantation of the Tambillo bajo sector, of the Colta canton, Chimborazo province. For this purpose, 100 individual specimens with straight shafts and without bifurcations were taken as a sample, and each individual’s commercial and total height, diameter at breast height, and diameters along the stem were measured, to determine the real volume of the wood using the Smalian and Newton formulas, the graphical method, and with a form factor of 0.70. Based on the measured data, a comparative analysis of the calculation of real volume by the method used was performed; the results obtained showed significant differences between calculation methods. In addition, five potential volume equations that presented the highest adjusted coefficient of determination and the lowest mean square error were selected. To verify the commercial volume calculated with the estimated form factors against the volume equations, the commercial volume was recalculated based on the form factors and equations found. The calculation of the commercial volume by the Smalian formula is taken as the exact value, and the other methods are taken as approximated values. Keywords: dasometry, form factor, forest plantation, volumen equations, commercial volume. Resumen La presente investigación propone: determinar el factor de forma de la especie Eucalyptus saligna en una plantación forestal comercial; para lo cual se toma como muestra 100 individuos con fustes rectos y sin bifurcaciones, a cada individuo se midió la altura comercial y total, diámetro a la altura del pecho y diámetros a lo largo del fuste, para determinar el volumen real de madera utilizando la fórmula de Smalian, Newton, método gráfico y con un factor de forma de 0,70. En base a los datos medidos, se realiza un análisis comparativo del cálculo de volumen real por método empleado, los resultados obtenidos mostraron diferencias significativas entre métodos de cálculo empleados. Además, se seleccionó 5 ecuaciones de volumen potenciales los cuales presentaron mayor coeficiente de determinación ajustado y menor error cuadrático medio. Para la verificación del volumen comercial calculado con los factores de forma estimados frente a las ecuaciones de volumen se vuelve a calcular el volumen comercial a partir de los factores de forma y ecuaciones encontrados, se toma como valor exacto el cálculo de volumen comercial por la fórmula de Smalian y como valor de aproximación los demás métodos. Palabras clave: dasometría, ecuaciones de volumen, factor de forma, plantación forestal, volumen comercial.

scholarly journals Numerically stable form factor of any polygon and polyhedron

2021 ◽  
Vol 54 (2) ◽  
pp. 580-587
Author(s):  
Joachim Wuttke
Keyword(s):  
Form Factor ◽  
Small Angle ◽  
Form Factors ◽  
Small Angle Scattering ◽  
Important Application ◽  
Divergence Theorem ◽  
Series Expansions ◽  
Stable Form ◽  
Application Domain ◽  
Angle Scattering

Coordinate-free expressions for the form factors of arbitrary polygons and polyhedra are derived using the divergence theorem and Stokes's theorem. Apparent singularities, all removable, are discussed in detail. Cancellation near the singularities causes a loss of precision that can be avoided by using series expansions. An important application domain is small-angle scattering by nanocrystals.

scholarly journals Ecosytem Services Assessment of Urban Forests of Adama City, Ethiopia

2020 ◽  
Author(s):  
Hingabu Hordofa Koricho ◽  
Ararsa Derese Seboka ◽  
Shaoxian Song
Keyword(s):  
Carbon Sequestration ◽  
Urban Environment ◽  
Carbon Storage ◽  
Azadirachta Indica ◽  
Eucalyptus Globulus ◽  
Carica Papaya ◽  
Urban Forest ◽  
Urban Forests ◽  
Pollution Removal ◽  
The City

Abstract Background: The recent urban challenges due to climate change and urban environment deterioration requires proper planning and inventories of urban forests. In this paper, trees and shrub information were used to estimate leaf area/biomass, carbon storage, carbon sequestration, pollution removal, and volatile organic compound (VOC) emissions, hydrological and functional values of Adama city urban forest. This study was conducted to assess and quantify the ecosystem services of urban forests of Adama city, Central Ethiopia.Results: The result of i-tree Eco model has indicated that the tree species such as Azadirachta indica, Eucalyptus globulus, Carica papaya and Delonix regia sequester high percentage of carbon which is approximately 14.7%, 7.4%, 7.3% and 6.2% of all annually sequestered carbon respectively. Besides, urban forests of the city was estimated to store 116,000 tons of carbon; the most carbons were stored by the species such as Eucalyptus globulus, Azadirachta indica, Carica papaya and Delonix regia that stores approximately 22.1%, 12.3%, 9.5% and 4.2% of all stored carbon respectively. Trees in Adama urban forests were estimated to produce 19.93 thousand tons of oxygen per year. It was estimated that trees and shrubs remove 188.3 thousand tons of air pollution due to O3, CO, NO2, PM2.5 and SO2 per year. In the city, 35 percent of the urban forest's VOC emissions were from Eucalyptus cinerea and Eucalyptus globulus. Besides, the monetary value of Adama urban forest in terms of carbon storage, carbon sequestration, and pollution removal was estimated to 16,588,470 ETB/yr, 118,283 ETB /yr and 12,162,701,080. 9 ETB /yr respectively.Conclusion: Urban forest of Adama city has significant contribution in terms of enhancing woody species diversity and the regulation of urban environment of the study area. From the management and conservation perspectives, urban forests of the study area needs consolidated interventions in terms of tree planting in bare areas and management works. Hence, reliable commitment should be demanded form the key stakeholders such as government, urban foresters and city dwellers.

The contribution of valence quarks in the nucleon GE and GM

2019 ◽  
Vol 34 (27) ◽  
pp. 1950148
Author(s):  
Negin Sattary Nikkhoo ◽  
Mohammad Reza Shojaei
Keyword(s):  
Experimental Data ◽  
Angular Momentum ◽  
Form Factor ◽  
Total Angular Momentum ◽  
Form Factors ◽  
Distribution Functions ◽  
The Other ◽  
Parton Distribution Functions ◽  
Nucleon Electromagnetic Form Factor ◽  
Elastic Form

The goal of this paper is to extract the flavor decomposition of nucleon electromagnetic form factor using the modified Gaussian and extended Regge ansatzes in the GPDs. We consider the CJ15 and JR09 parton distribution functions for both of these ansatzes in calculating the nucleon elastic form factors. Our results are compared with experimental data in the range [Formula: see text] 4-momentum transfers. Also, we calculate the total angular momentum carried by quarks, the gravitational form factors, and the transverse gravitational density for quarks of the nucleon. In the end, our results are compared with the other studies.

Heterogeneous sensing in a multifunctional soft sensor for human-robot interfaces

2020 ◽  
Vol 5 (49) ◽  
pp. eabc6878 ◽  
Author(s):  
Taekyoung Kim ◽  
Sudong Lee ◽  
Taehwa Hong ◽  
Gyowook Shin ◽  
Taehwan Kim ◽  
...  
Keyword(s):  
Form Factor ◽  
Form Factors ◽  
Soft Sensor ◽  
Compact Form ◽  
Original Form ◽  
Entire Body ◽  
Soft Sensors ◽  
Input Stimulus ◽  
Human Robot Interfaces ◽  
Deformation Modes

Soft sensors have been playing a crucial role in detecting different types of physical stimuli to part or the entire body of a robot, analogous to mechanoreceptors or proprioceptors in biology. Most of the currently available soft sensors with compact form factors can detect only a single deformation mode at a time due to the limitation in combining multiple sensing mechanisms in a limited space. However, realizing multiple modalities in a soft sensor without increasing its original form factor is beneficial, because even a single input stimulus to a robot may induce a combination of multiple modes of deformation. Here, we report a multifunctional soft sensor capable of decoupling combined deformation modes of stretching, bending, and compression, as well as detecting individual deformation modes, in a compact form factor. The key enabling design feature of the proposed sensor is a combination of heterogeneous sensing mechanisms: optical, microfluidic, and piezoresistive sensing. We characterize the performance on both detection and decoupling of deformation modes, by implementing both a simple algorithm of threshold evaluation and a machine learning technique based on an artificial neural network. The proposed soft sensor is able to estimate eight different deformation modes with accuracies higher than 95%. We lastly demonstrate the potential of the proposed sensor as a method of human-robot interfaces with several application examples highlighting its multifunctionality.

Sign in / Sign up

Export Citation Format

Share Document