Search results for "DEPTH"
showing 10 items of 408 documents
Trends of some high quantiles of average and extremes inter-arrival timesand rainfall depths at daily scale for an Italian Sub-Alpine area
2015
Modeling of rainfall statistical structure represents an important research area in hydrology, meteorology, atmospheric physics and climatology, because of the several theoretical and practical implications. The statistical inference of the alternation of wet periods (WP) and dry periods (DP) in daily rainfall records can be achieved through the modelling of inter-arrival time-series (IT), defined as the succession of times elapsed from a rainy day and the one immediately preceding it. It has been shown previously that the statistical structure of IT can be well described by the 3-parameter Lerch distribution (Lch). In this work, Lch was successfully applied to IT data belonging to a sub-al…
Chemical, biochemical and microbial diversity through a Pachic Humudept profile in a temperate upland grassland
2013
There is great interest in understanding the factors that drive soil microbial activity and community composition in upland grassland ecosystems. We investigated the role of vertical gradients of chemical properties and various soluble C and N pools on soil microbial community structure by using a combination of chemical and biochemical methods coupled with PCR-denaturing gradient gel electrophoresis (DGGE) community fingerprinting and phospholipid fatty acid (PLFA) profiling. Soil samples were collected at increasing depth from a temperate upland grassland. Soil organic matter-related pools (total organic C and total Kjeldahl N) and functionally related active pools (microbial biomass C an…
Phytoplankton assemblages in twenty-one Sicilian reservoirs: relationships between species composition and environmental factors
2000
Data collected in a limnological survey, carried out between 1987 and 1988 on 21 Sicilian reservoirs of varying trophic state, were ordinated using CANOCO 3.1 to generalise the way in which the structure of phytoplankton assemblage is conditioned by both physical and chemical variables. The results showed that in these man-made lakes, characterised by conspicuouswater-level fluctuations, the annual and interannual variability in the abundance and composition of phytoplankton may be strongly influenced by their peculiar hydraulic regimes rather than by nutrient availability. In particular, it was highlighted that, from the early summer, water abstraction often leads to increased circulation …
Monitoring tropical forests under a functional perspective with satellite-based vegetation optical depth.
2020
Monitoring ecosystem functions in forests is a priority in a climate change scenario, as climate-induced events may initially alter the functions more than slow-changing attributes, such as biomass. The ecosystem functional properties (EFPs) are quantities that characterize key ecosystem processes. They can be derived by point observations of gas and energy exchanges between the ecosystems and the atmosphere that are collected globally at FLUXNET flux tower sites and upscaled at ecosystem level. The properties here considered describe the ability of ecosystems to optimize the use of resources for carbon uptake. They represent functional forest information, are dependent on environmental dri…
Continuous hand openness detection using a Kinect-like device
2014
This paper presents a novel method to reproduce in real time the opening and closing gestures of a human hand, animating a three-dimensional model of it. In other works, this result can be achieved by mapping a set of significant points of a real hand on the corresponding points of the model to animate. We propose an alternative way to produce the same effect without mapping points, but using a level-based estimation of the degree of opening of the hand. The experiments have been executed using Microsoft KinectTM, but the method would work on any other Kinect-like devices (as defined herein). The results obtained are particularly encouraging and demonstrate real-time performance of the syst…
Synergistic integration of optical and microwave satellite data for crop yield estimation
2019
Developing accurate models of crop stress, phenology and productivity is of paramount importance, given the increasing need of food. Earth observation (EO) remote sensing data provides a unique source of information to monitor crops in a temporally resolved and spatially explicit way. In this study, we propose the combination of multisensor (optical and microwave) remote sensing data for crop yield estimation and forecasting using two novel approaches. We first propose the lag between Enhanced Vegetation Index (EVI) derived from MODIS and Vegetation Optical Depth (VOD) derived from SMAP as a new joint metric combining the information from the two satellite sensors in a unique feature or des…
Depth-of-Field Enhancement in Integral Imaging by Selective Depth-Deconvolution
2014
One of the major drawbacks of the integral imaging technique is its limited depth of field. Such limitation is imposed by the numerical aperture of the microlenses. In this paper, we propose a method to extend the depth of field of integral imaging systems in the reconstruction stage. The method is based on the combination of deconvolution tools and depth filtering of each elemental image using disparity map information. We demonstrate our proposal presenting digital reconstructions of a 3-D scene focused at different depths with extended depth of field.
Sequent Depth Ratio of a B-Jump
2011
A B-jump is defined as the jump having the toe section located on a positively sloping upstream channel and the roller end on a downstream horizontal channel. This jump often occurs in the stilling basins with a horizontal bottom and located downstream of a steep channel. For a B-jump, a completely theoretical approach is not sufficient to solve the momentum equation and to establish the sequent depth ratio. In this paper, by using the laboratory measurements carried out in this investigation, some available empirical relationships useful for estimating the sequent depth ratio are tested. Then, by using the Π theorem of the dimensional analysis and the incomplete self-similarity theory, a g…
New stage-discharge relationship for cylindrical and semi-cylindrical edged sluice gates
2019
Abstract Gates are simple hydraulic structures which have been widely used for flow control and measurement in irrigation networks. In this paper new sluice gates with cylindrical and semi-cylindrical edges were introduced and the flow movement below these types of gates was experimentally investigated for both free- and submerged-flow conditions. The Buckingham theorem of dimensional analysis and the self-similarity theory were applied for developing the stage-discharge relationships for the two investigated flow conditions. For these cylindrical and semi-cylindrical edged gates and a free-flow condition, the proposed stage-discharge relationship was characterized by an estimate error less…
Pengembangan Kriteria dan Klasifikasi Tingkat Kekritisan Lahan pada Skala Tinjau di Kawasan Budidaya Pertanian Lahan Kering di Kabupaten Bogor
2018
<em>The objectives of this research are to develop critical land criteria and classification on the reconnaissance scales. The method used in this research is survey method through case studies. Data analysis methods include: bivariate correlation analysis, cluster analysis, and discriminant analysis. The results showed development criteria at reconnaissance scale resulted three determinant variables, namely: effective soil depth, stones, and degree of erosion; and produced two classes of critical land, namely: Critical class and Non-Critical class.</em>