Tree height and crown shape, as results of competitive games

1985 ◽  
Vol 112 (2) ◽  
pp. 279-297 ◽  
Author(s):  
Yoh Iwasa ◽  
Dan Cohen ◽  
Jesus Alberto Leon
Keyword(s):  
Tree Height ◽  
Crown Shape ◽  
Competitive Games

scholarly journals ACCURACY ASSESSMENT OF CROWN DELINEATION METHODS FOR THE INDIVIDUAL TREES USING LIDAR DATA

2016 ◽  
Vol XLI-B8 ◽  
pp. 585-588
Author(s):  
K. T Chang ◽  
C. Lin ◽  
Y. C. Lin ◽  
J. K. Liu
Keyword(s):  
Forest Canopy ◽  
Accuracy Assessment ◽  
Tree Height ◽  
Experimental Results ◽  
Estimation Methods ◽  
Surface Model ◽  
Individual Tree ◽  
Free Process ◽  
Crown Shape ◽  
Individual Trees

Forest canopy density and height are used as variables in a number of environmental applications, including the estimation of biomass, forest extent and condition, and biodiversity. The airborne Light Detection and Ranging (LiDAR) is very useful to estimate forest canopy parameters according to the generated canopy height models (CHMs). The purpose of this work is to introduce an algorithm to delineate crown parameters, e.g. tree height and crown radii based on the generated rasterized CHMs. And accuracy assessment for the extraction of volumetric parameters of a single tree is also performed via manual measurement using corresponding aerial photo pairs. A LiDAR dataset of a golf course acquired by Leica ALS70-HP is used in this study. Two algorithms, i.e. a traditional one with the subtraction of a digital elevation model (DEM) from a digital surface model (DSM), and a pit-free approach are conducted to generate the CHMs firstly. Then two algorithms, a multilevel morphological active-contour (MMAC) and a variable window filter (VWF), are implemented and used in this study for individual tree delineation. Finally, experimental results of two automatic estimation methods for individual trees can be evaluated with manually measured stand-level parameters, i.e. tree height and crown diameter. The resulting CHM generated by a simple subtraction is full of empty pixels (called "pits") that will give vital impact on subsequent analysis for individual tree delineation. The experimental results indicated that if more individual trees can be extracted, tree crown shape will became more completely in the CHM data after the pit-free process.

scholarly journals Growth features of apple varieties and forms with natural and compact crown types

2021 ◽  
Vol 845 (1) ◽  
pp. 012014
Author(s):  
A S Zemisov ◽  
A N Youshkov ◽  
N N Saveleva ◽  
L V Grigoreva ◽  
N V Borzykh ◽  
...  
Keyword(s):  
Tree Height ◽  
Cost Effective ◽  
Federal State ◽  
Scientific Center ◽  
Apple Varieties ◽  
Crown Volume ◽  
Crown Shape ◽  
The Rich ◽  
Growth Features ◽  
High Degree

Abstract This research explores the compactness of apple varieties and forms with different types of crown. Orchards on semi-vigorous rootstocks with density and high density planting systems are cost-effective in modern horticulture. For making such gardens, it is necessary to have trees with special compact crown shape. They ensure the high-quality fruits production, meeting the requirements of world standards. To date the most perspective apple varieties and forms for domestic intensive gardening from the rich gene pool of the Selection and Genetic Center of Federal State Scientific Institution «I. V. Michurin Federal Scientific Center» are identified. Varieties of folk domestic and foreign breeding took part in the creation of new genotypes. Apple varieties and promising forms (more than 160 genotypes), including from near and far abroad selection, were used as materials for crown features studying. We conducted our study by the following indicators: tree height, crown volume, “degree of compactness” and the shoot-forming ability. We found that the genotypes Sholokhovskoye, Zvezda Artemyeva, 25-7(11), 40-9(8), 36-8(21), 40-9(6), 8-7(72), 40-9(7), 36-8(17), 62-5(140) have optimal crown parameters. We recommend their use for industrial horticulture and further breeding to create restrained growth, low-volume crown, and a high degree of compactness varieties.

scholarly journals An Improved Tree Height Measurement Technique Tested on Mature Southern Pines

2008 ◽  
Vol 32 (1) ◽  
pp. 38-43 ◽  
Author(s):  
Don C. Bragg
Keyword(s):  
Tree Height ◽  
Real Point ◽  
Horizontal Distance ◽  
Height Measurement ◽  
Similar Triangle ◽  
Height Determination ◽  
Southern Pines ◽  
Crown Shape ◽  
Tangent Method ◽  
Similar Triangles

Abstract Virtually all techniques for tree height determination follow one of two principles: similar triangles or the tangent method. Most people apply the latter approach, which uses the tangents of the angles to the top and bottom and a true horizontal distance to the subject tree. However, few adjust this method for ground slope, tree lean, crown shape, and crown configuration, making errors commonplace. Given documented discrepancies exceeding 30% with current methods, a reevaluation of height measurement is in order. The sine method is an alternative that measures a real point in the crown. Hence, it is not subject to the same assumptions as the similar triangle and tangent approaches. In addition, the sine method is insensitive to distance from tree or observer position and can not overestimate tree height. The advantages of the sine approach are shown with mature southern pines from Arkansas.

Do wide crowns in arid woodland trees reflect hydraulic limitation and reduction of self-shading?

2014 ◽  
Vol 41 (12) ◽  
pp. 1221 ◽  
Author(s):  
Martín Escoto-Rodríguez ◽  
José M. Facelli ◽  
Jennifer R. Watling
Keyword(s):  
Arid Regions ◽  
Tree Height ◽  
Lateral Spreading ◽  
Light Limitation ◽  
Hydraulic Limitation ◽  
Trade Offs ◽  
Crown Shape ◽  
Horizontal Growth ◽  
Lateral Branches ◽  
Topographic Positions

In arid regions many tree species develop broad crowns. A number of hypotheses involve trade-offs between growth in height and horizontal spreading, but there is no explanation for the switch from vertical to horizontal growth during development. Using Acacia papyrocarpa Benth as a model, we measured tree height and crown shape across different sites and topographic positions. We also measured δ13C of phyllodes from crown tops and lateral spreading branches. Trees were significantly taller at the base of a hill, where water availability is typically greater, than on the adjacent steep hillslope. In contrast, δ13C from the treetops was not significantly different across this topographic gradient, despite variation in tree height. In addition, δ13C was higher at treetops than in lower, lateral branches. These observations are consistent with hydraulic limitation to tree height. The shape of mature and young crowns in open environments was not symmetrical. At all sites, branches were shortest, but tree crowns tallest, on south-facing (i.e. shadiest) aspect of crowns. This suggests that light limitation may also affect crown development. If upper branches become water-limited and lower branches light-limited, then middle lateral branches become the less-stressed part of the crown and may grow more, producing a broad crown.

scholarly journals Features and allometric relationships characterising trees on farmland – an example from Chainpur VDC, Chitwan

1970 ◽  
Vol 17 (2) ◽  
pp. 18-26 ◽  
Author(s):  
Henrik Meilby ◽  
Lila Puri
Keyword(s):  
Tree Species ◽  
Basal Area ◽  
Tree Height ◽  
Agricultural Landscapes ◽  
Wood Products ◽  
Melia Azedarach ◽  
Local Climate ◽  
Allometric Models ◽  
Crown Cover ◽  
Crown Shape

Trees on farmland are important sources of fodder, food and a range of wood products and improve local climate and the ecological quality of agricultural landscapes. In spite of this, little is known about the composition of farm tree populations, farmer's management and the resulting characteristics of the trees. In a case study in Chainpur VDC, Chitwan, all trees with diameter 3 2 cm 0.5 metres above ground were enumerated and mapped within 8.44 ha of farmland. The total number of trees was 898, corresponding to a density of 106 ha-1. The basal area 0.5 and 1.3 m above ground were 2.00 and 1.42 m2ha-1, respectively, and the total crown cover was 8.76%. The number of species recorded was 63, most of which were represented by only a few individuals. The most frequent species were Melia azedarach L. (Bakaino, 238 individuals), Bauhinia purpurea Wall. (Tanki, 111 individuals) and Ficus hispida L.f. (Khasreto, 87 individuals). Measurements of diameter and height of crown and stem were done for a sample comprising 81% of the trees. In addition, ocular assessment of the lopping intensity was carried out. Based on these observations, a set of allometric models relating stem diameter, tree height, crown width, crown length and lopping were developed and used for preparation of schematic tree silhouettes. Marked differences between tree species were observed with regard to crown shape and the effect of lopping on shape. Key words: allometric models, farmer's tree species preferences, fodder tree species, lopping assessment, tree silhouettes     doi: 10.3126/banko.v17i2.2152 Banko Janakari, Vol. 17, No. 2, 18-26

scholarly journals ACCURACY ASSESSMENT OF CROWN DELINEATION METHODS FOR THE INDIVIDUAL TREES USING LIDAR DATA

2016 ◽  
Vol XLI-B8 ◽  
pp. 585-588
Author(s):  
K. T Chang ◽  
C. Lin ◽  
Y. C. Lin ◽  
J. K. Liu
Keyword(s):  
Forest Canopy ◽  
Accuracy Assessment ◽  
Tree Height ◽  
Experimental Results ◽  
Estimation Methods ◽  
Surface Model ◽  
Individual Tree ◽  
Free Process ◽  
Crown Shape ◽  
Individual Trees

Forest canopy density and height are used as variables in a number of environmental applications, including the estimation of biomass, forest extent and condition, and biodiversity. The airborne Light Detection and Ranging (LiDAR) is very useful to estimate forest canopy parameters according to the generated canopy height models (CHMs). The purpose of this work is to introduce an algorithm to delineate crown parameters, e.g. tree height and crown radii based on the generated rasterized CHMs. And accuracy assessment for the extraction of volumetric parameters of a single tree is also performed via manual measurement using corresponding aerial photo pairs. A LiDAR dataset of a golf course acquired by Leica ALS70-HP is used in this study. Two algorithms, i.e. a traditional one with the subtraction of a digital elevation model (DEM) from a digital surface model (DSM), and a pit-free approach are conducted to generate the CHMs firstly. Then two algorithms, a multilevel morphological active-contour (MMAC) and a variable window filter (VWF), are implemented and used in this study for individual tree delineation. Finally, experimental results of two automatic estimation methods for individual trees can be evaluated with manually measured stand-level parameters, i.e. tree height and crown diameter. The resulting CHM generated by a simple subtraction is full of empty pixels (called "pits") that will give vital impact on subsequent analysis for individual tree delineation. The experimental results indicated that if more individual trees can be extracted, tree crown shape will became more completely in the CHM data after the pit-free process.

Levels of Theory-of-Mind Reasoning in Competitive Games

2009 ◽  
Author(s):  
Adam S. Goodie ◽  
Prashant Doshi ◽  
Diana L. Young
Keyword(s):  
Theory Of Mind ◽  
Competitive Games

Application of Computational Mechanics to Tire Design—Yesterday, Today, and Tomorrow

2011 ◽  
Vol 39 (4) ◽  
pp. 223-244 ◽  
Author(s):  
Y. Nakajima
Keyword(s):  
Finite Element ◽  
New Technologies ◽  
Computational Mechanics ◽  
Design Procedure ◽  
Side Wall ◽  
Rolling Resistance ◽  
Optimization Techniques ◽  
Stress Strain ◽  
Element Analysis ◽  
Crown Shape

Abstract The tire technology related with the computational mechanics is reviewed from the standpoint of yesterday, today, and tomorrow. Yesterday: A finite element method was developed in the 1950s as a tool of computational mechanics. In the tire manufacturers, finite element analysis (FEA) was started applying to a tire analysis in the beginning of 1970s and this was much earlier than the vehicle industry, electric industry, and others. The main reason was that construction and configurations of a tire were so complicated that analytical approach could not solve many problems related with tire mechanics. Since commercial software was not so popular in 1970s, in-house axisymmetric codes were developed for three kinds of application such as stress/strain, heat conduction, and modal analysis. Since FEA could make the stress/strain visible in a tire, the application area was mainly tire durability. Today: combining FEA with optimization techniques, the tire design procedure is drastically changed in side wall shape, tire crown shape, pitch variation, tire pattern, etc. So the computational mechanics becomes an indispensable tool for tire industry. Furthermore, an insight to improve tire performance is obtained from the optimized solution and the new technologies were created from the insight. Then, FEA is applied to various areas such as hydroplaning and snow traction based on the formulation of fluid–tire interaction. Since the computational mechanics enables us to see what we could not see, new tire patterns were developed by seeing the streamline in tire contact area and shear stress in snow in traction.Tomorrow: The computational mechanics will be applied in multidisciplinary areas and nano-scale areas to create new technologies. The environmental subjects will be more important such as rolling resistance, noise and wear.

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