نتایج جستجو برای: crown height
تعداد نتایج: 118047 فیلتر نتایج به سال:
A simple simulator was developed to test whether airborne laser scanning can be used as a strip sampling tool for forest inventory purposes. The simulator is based on the existing two stages, grid based laser inventory procedure. A population of trees was created using an existing forest stand structure generator. Each tree was represented by means of its 3D-crown model derived from airborne la...
Orangutans are believed to have close biological affinities to humans. Teeth being the hardest tissue provide useful information on primate evolution. Furthermore, knowledge of the pulp chamber and root canal morphology is important for dental treatment. A female Bornean orangutan and a Sumatran male orangutan skull were available for this study. Both of their dentitions, comprising 50 teeth, w...
[1] Hydraulic resistance of riparian forests is an unknown but important term in flood conveyance modeling. Lidar has proven to be a very important new data source to physically characterize floodplain vegetation. This research outlines a recent campaign that aims to retrieve vegetation fluid resistance terms from airborne laser scanning to parameterize trunk roughness. Information on crown cha...
Hundreds of cankers caused by Ceratocystis smalleyi are associated with hickory bark beetle-attacked bitternut hickory exhibiting rapid crown decline in the north-central and northeastern United States. Discolored sapwood colonized by the fungus commonly underlies the cankers. Field studies were conducted to test the hypothesis that C. smalleyi infections cause vascular system dysfunction in in...
There is growing recognition of the role of mechanistic scaling laws in shaping ecological pattern and process. While such theoretical relationships explain much of the variation across large scales, at any particular scale there is important residual variation that is left unexplained among species, among individuals within a species, and within individuals themselves. Key questions remain on ...
Dental morphogenesis and cellular differentiation are expressed in the fully formed tooth by the topography of the dentin-enamel junction and outer enamel surface. These boundaries can be differentiated using a variety of imaging systems. In this study, we used serial microCT imaging to provide accurate 3D reconstructions of developing lower human second deciduous molars. These were used to qua...
High density airborne LiDAR, for example FLI-MAP 400 data, has opened an opportunity for individual tree measurement. This paper presents a method for individual tree delineation and undergrowth vegetation removal in forest area. The delineation of individual trees involves two steps namely 1) tree crown delineation based on density of high points (DHP) and 2) separation of dominant trees and u...
OBJECTIVES The aim of this study was to investigate the possibility to use high-frequency ultrasound imaging for the assessment of periodontal structures. MATERIAL AND METHODS A commercially available ultrasound scanner (Ultrasonix SonoTouch) with a linear 1.5 cm footprint, wideband 8 - 40MHz transducer was used, with external transcutaneous approach. A number of 4 patients with healthy perio...
We studied the evolution of leaf size, sapling canopy allometry, and related traits in 17 Acer species growing in the understory of temperate deciduous forests, using parsimony methods, randomization tests, and independent contrasts calculated on a phylogeny inferred from nuclear ribosomal internal transcribed spacer (ITS) sequences. Bivariate correlations and multivariate analyses indicated tw...
Tree species identification is important for a variety of natural resource management and monitoring activities including riparian buffer characterization, wildfire risk assessment, biodiversity monitoring, and wildlife habitat assessment. Intensity data recorded for each laser point in a LIDAR system is related to the spectral reflectance of the target material and thus may be useful for diffe...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید