Top PDF High-resolution Mapping of Forest Carbon Stocks in the Colombian Amazon

High-resolution Mapping of Forest Carbon Stocks in the Colombian Amazon

High-resolution Mapping of Forest Carbon Stocks in the Colombian Amazon

To scale from the plot to landscape level, LiDAR studies have often been closely tied to calibration plots distributed throughout the mapping coverage. However, the logistical and cost burden of establishing an extensive plot network may limit the utility of LiDAR for carbon mapping, particularly in forests that remain very remote, either by distance or by difficult terrain. To address this problem, Asner et al. (2012a) recently

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High-resolution mapping of forest carbon stocks in the Colombian Amazon

High-resolution mapping of forest carbon stocks in the Colombian Amazon

We validated the universal LiDAR calibration equation using traditional forest inventory techniques with allometric regres- sion equations (Table S1). Although we used the same plots, this validation was critical to determine whether two simple regional constants (i.e., SC and WD) could substitute for tra- ditional field inventory. For dead trees and palms, we utilized growthform-specific equations. Lianas were considered, but none were detected over the minimum size class (10 cm dbh). For all other trees, we utilized a general moist forest model of Chave et al. (2005). We corrected for local height varia- tion by directly measuring the heights of the largest trees in all plots (> 50 cm dbh) and additional trees spanning a range of stem diameters using a laser hypsometer (Impulse-200, LaserTech Inc., USA). For the remaining trees, we produced a model relating height and diameter using maximum like- lihood analysis (Fig. S3; R Development Core Team, 2011). Wood density values were assigned based on genus- (33 %) or family-level (42 %) identifications according to Chave et al. (2009), and are detailed in Table S2. These values were determined by averaging all listings at the genus- and family- level within the database. In the absence of such an identifi- cation (25 %), a regional estimate of 0.58 was applied (ter Steege et al., 2006). Plot centers were determined using a global positioning system (GPS) with differential correction (Leica GS-50, Leica Geosystems Inc., Switzerland), which provided < 1 m positional uncertainty in most cases. 2.6 Regional upscaling based on stratification
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Sensitivity of the Amazon biome to high resolution climate change projections

Sensitivity of the Amazon biome to high resolution climate change projections

The leaf area index (LAI) and the net primary production (NPP) of each PFT depends on the quantity of carbon absorbed by the vegetation during the year. Therefore, these are good parameters to indicate the impact of climate change in the rainforest biome. Figure 7 shows the 5-year mean variation of LAI and NPP for the PFTs that exist in the nine grid points surrounding the Santarem-k83 site. A 5-year average was applied to the time series to reduce the interannual variability signal and to show more clearly the trend. The linear negative trends of LAI and NPP in tropical broadleaf evergreen trees and tropical broadleaf drought-deciduous trees in both scenarios have statistical significance of 99,9%. The RCP8.5 scenario has a more pronounced decreasing trend than RCP4.5 scenario. However, for the functional type of warm (c4) grasses, increasing trend has statistical significance of 99,9% in the RCP4.5 and no statistical significance in the RCP8.5 scenario. The decrease of LAI and NPP in forest PFTs is due to the neutralization of CO 2 fertilization effect caused by reduced rainfall (Figure 6) and soil humidity simulated by the Eta-HadGEM2-ES in this area.
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A tale of two "forests": random forest machine learning AIDS tropical forest carbon mapping.

A tale of two "forests": random forest machine learning AIDS tropical forest carbon mapping.

Machine-learning algorithms have the potential to substantially improve spatial modeling of carbon stocks in tropical forests and possibly other ecosystems. Although some drawbacks remain unresolved—namely over-fitting and spatial autocorrelation of model errors—Random Forest may provide a viable pathway to improve large-area modeling of carbon stocks over existing methods such as stratification. This is particularly true in large- scale, high-resolution modeling exercises that are currently intractable when using parametric statistical approaches such as simultaneous autoregressive modeling due to computational limitations (e.g., SAR [37,45]). We emphasize that our modeling outcomes greatly benefited from an unprecedentedly high density of airborne LiDAR data over a large geographic region, and this suggests that high data density may be critical moving forward. Further, testing Random Forest against other modeling approach- es beyond stratification (e.g., k-nearest neighbor, maximum entropy) is also critical to determine its ultimate utility in carbon mapping.
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High spatial resolution land use and land cover mapping of the Brazilian Legal Amazon in 2008 using Landsat-5TM and MODIS data

High spatial resolution land use and land cover mapping of the Brazilian Legal Amazon in 2008 using Landsat-5TM and MODIS data

Annual crops thought of by many as a key force for deforestation in the Amazon, covered circa 5% of the area mapped as deforested by PRODES in 2008. This result differs from Morton et al. (2006), which suggested that soybeans crops were one of the major deforestation vectors in Mato Grasso, between 2001 and 2004. Part of this difference can be explained by the temporal limitation, 2001 up to 2004, when deforestation data indicated a high rate of forest conversion (INPE 2015). But this period is also marked by a sharp change in the soybean market, caused mainly by the establishment of the soy moratorium by the major traders and the implementation of the Rural Environmental Registry (Rudorff et al. 2011; Gibbs et al. 2014;). All these types of dynamics underscore the importance of monitoring changes over time within of the Brazilian Amazon so as to assess the advance of agriculture within the Amazon biome in face of other drivers for land use change.
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Assessment Of Some Acceleration Schemes In The Solution Of Systems Of Linear Equations.

Assessment Of Some Acceleration Schemes In The Solution Of Systems Of Linear Equations.

Richardson with SOR, Chebyshev with Gauss-Seidel and Chebyshev with SOR. The iterative schemes were applied to Banded system, Tridiagonal systems and SPD system with varying dimensions. The Krylov subspace methods: GMRES, QMR, MINRES and BiCGSTAB converged to an approximate solutions less than or equal to the dimension of the coefficient matrix for each identified systems of linear equations. Again, Chebyshev and Richardson acceleration methods were the fastest convergence methods in terms of number of iterations. Again, Residual smoothing and the accelerated gradient schemes should be used for large and sparse systems of linear equations. The acceleration processes were very efficient when solving large and sparse systems of linear equation and therefore useful especially for systems resulting from the solution of partial differential equations.
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Evaluation of the altimetry from SRTM-3 and planimetry from high-resolution PALSAR FBD data for semi-detailed topographic mapping in the Amazon Region

Evaluation of the altimetry from SRTM-3 and planimetry from high-resolution PALSAR FBD data for semi-detailed topographic mapping in the Amazon Region

Usually, elevation information is expressed in car- tographic maps by contour lines. The results confirmed the altimetric and planimetric qualities of the contour lines produced from SRTM-3 DSM, and highlighted its potential as an input for cartographic map production at semi-detailed scale. On the other hand, due to the ability of FDB PALSAR images to highlight target vari- ations on the terrain, distinct image patterns with arrays of tonal/textural patterns can be meaningfully related to important layers (drainages, roads, land-use, etc.), which are also necessary as thematic information for mapping purposes. Figure 8 shows the topographic map of the study area produced through the combination of infor-
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High-resolution mutation mapping reveals parallel experimental evolution in yeast.

High-resolution mutation mapping reveals parallel experimental evolution in yeast.

, d, can1; and e, LYS5. See Figure 2E and Table 1 for mapping deviations of predicted peak centers from the corresponding linked genes and estimated 95% confidence intervals. (B), (D), (F), and (H) are y-axis close-ups of (A), (C), (E), and (G), respectively. A single false-positive peak on Chromosome 10 was detected in the pools selected for resistance to geneticin, hygromycin, and nourseothricin ([A–D]; labeled with a green asterisk). See text for possible explanation for observing this peak. The signal-to-noise levels are high and appear to slightly decrease as the segregant pools size decreases. A sliding window of 50 SFPs was used for all plots except for (I), where a smoothing window of constant chromosome size (35 kb) was used. The height of the LYS5 peak has increased disproportionately by using a smoothing window of 35 kb (I) versus 50 SFPs (G–H). We believe this reflects the lower SFP density around LYS5 (0.52 SFPs/kb), which is ;1.7-fold lower than the density around can1 (0.88 SFPs/kb) and than the genome’s mean SFP density (an interval of 30 kb around the genes was used for SFP density comparison). (J) To test whether we could map genes that are not fully enriched in a selected pool of segregants, we mixed the pool of segregants selected in geneticin, hygromycin, and nourseothricin (from [A]) with the control pool at a 1:1 ratio. About 75% of the segregants in the resulting pool should carry the three drug resistance genes if the initial selection was perfect. The three largest peaks correspond to the three mapped genes though the signal is much lower than in (A) (see also Figure S5). The x-axis labels are the numbers of the chromosomes, which are shown to scale.
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Investigating The Use Of Mobile Computing In Zimbabwe Polytechnics Case Of A Polytechnic In Zimbabwe

Investigating The Use Of Mobile Computing In Zimbabwe Polytechnics Case Of A Polytechnic In Zimbabwe

Zimmerman (1999) in his article titled ―Mobile Computing: Characteristics, Benefits, and the Mobile fra mework‖ defined mobile computing as ―the use of computing devices, which usually interact in some way with a centralised information system while away from the normal fixed workplace‖. He went on to say that, Mobile computing technology enables the mobile person to create, access, process, store and communicate information without being constrained to a single location. It is on the above basis that this researcher views mobile computing as embracing a host of portable technologies the can access internet using wireless fidelity (WIFI). These range from notebook computers to tablets, to smartphones and e-book readers. Such devices have brought about Mobile learning (m-Learning) in Zimbabwe Polytechnics, enabling staff and students to share academic resources, be able to research and develop applications from wherever they are. Zimmerman (1999) went on to identify mobile computing hardware, software and communications in use then. He identified hardware as palmtops, clamshells, handheld Pen Keys, pen slates, and laptops. The characteristics of such devices in terms of screen size was small, processing capability was limited and supported a few mobile applications. Over the years mobile devices have improved in such characteristics to make mobile computing easy, fast and user friendly. Great improvements also came with the associated systems software, with the modern devices now running on Android, Symbian and windows 8 mobile, as compared to then when MS DOS, Windows 3.1, Pen DOS were used. In communications Zimmerman talked of internet speeds in kilobytes per second (Kbps), while today’s communications devices have speeds of gigabytes per second (Gbps
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Scaling net ecosystem production and net biome production over a heterogeneous region in the western United States

Scaling net ecosystem production and net biome production over a heterogeneous region in the western United States

et al., 2000), fine scale phenomena associated with anthro- pogenic and natural disturbances (Korner, 2003; Pacala et al., 2001), and temporal variation at the seasonal and interannual scales. Carbon budget approaches based on forest inventory information, e.g. Kauppi et al. (1992), are poorly resolved spatially and temporally, do not reveal the mechanisms ac- counting for changes in carbon stocks, and miss carbon flux associated with non-forest vegetation. Alternatively, a pro- cess modeling approach – with inputs of high spatial resolu- tion remote sensing data and distributed meteorological data – can provide estimates of net ecosystem production (NEP, sensu Lovett et al., 2006) for potential comparison with NEP fluxes from inverse modeling studies, and provide estimates of net biome production (NBP, sensu Schulze et al., 2000) for comparison with carbon accounting being done in sup- port of the Framework Convention on Climate Change (UN- FCCC, 1992). In this analysis, we apply a process modeling approach to generate a carbon budget over the state of Ore- gon (2.5×10 5 km 2 ) in western North America between 1980 and 2002. The period included a significant reduction in for- est harvesting on public lands, several extreme climate years, and an exceptional fire year.
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Comparative high-resolution mapping of the wax inhibitors Iw1 and Iw2 in hexaploid wheat.

Comparative high-resolution mapping of the wax inhibitors Iw1 and Iw2 in hexaploid wheat.

The outermost wax layer protects plants from many types of biotic and abiotic stresses, such as drought, phytophagous insects, pathogens, solar radiation, and freezing temperatures [1,2]. One of the most important roles of the cuticle is to limit transpiration to reduce water loss and this provides a key mechanism for plant survival in water-limited environments, such as deserts, high mountains, saline-alkali lands, and coastal ecosystems [3,4]. Worldwide, bread wheat (Triticum aestivum L.) is one of the most important food sources for human beings. The wheat leaf, stem and, in some cases, spike surfaces are coated with cuticular waxes that confer a glaucousness characteristic [5,6]. Physiological studies in wheat by Johnson et al. [7] and Richards et al. [8] showed that glaucousness reduces transpiration and increased water use efficiency. More recently Zhang et al. demonstrated that glaucousness reduced cuticle permeability in the terms of non- stomatal water loss and chlorophyll efflux [9]. Bread wheat cultivars with non-glaucousness traits exhibit significant yield increases with reduced solar radiation losses that enable continued photosynthesis during the grain filling period [10], and the trait may also provide resistance to aphids [11].
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SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

)n the context of the cohesion policy, solidarity must represent a support for development . For that purpose, solidarity can be seen as a help for self‐help and its success depends a great deal on the capacity and the training of the people to whom the support of making maximum profit out of these addresses to. This support does not mean exclusively financial support, although it is necessary and important but, of all things, it means an exchange of experiences and cooperation, the development of capacity through training, open discussions with the interested factors and last but not least a critic, but a constructive dialogue between the various levels of government: European, national, regional, local. )n other words, a functional labor market should represent a catalyst for the general objective of the European Union – social and economical cohesion – because it has in view the connections with the different markets of the services and of the goods and generates the necessary income for supporting the participation of the individuals, bringing them together, placing them in collaborations. )n this context, the starting points for promoting the inclusion through the activities of social economy have in view: adapting the institutional environment, developing the public‐private partnership, developing the social dialogue between players, investments in the human capital and supporting the exchange of good practices within the European Union.
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MULTI-SCALE VEGETATION CLASSIFICATION USING EARTH OBSERVATION DATA OF THE SUNDARBAN MANGROVE FOREST, BANGLADESH

MULTI-SCALE VEGETATION CLASSIFICATION USING EARTH OBSERVATION DATA OF THE SUNDARBAN MANGROVE FOREST, BANGLADESH

The Sundarban mangrove forest is the largest continuous block of mangrove forest in the world, located in south-western Bangladesh and in south-eastern India (Hussain and Karim, 1994). The Sundarban Reserved Forest (SRF), as known officially in Bangladesh (Forest Department 2008), has been declared a UNESCO World Heritage site for its unique ecosystem, and as a RAMSAR site for its importance as an internationally significant wetland (RAMSAR, 2007, UNESCO, 1997). The forest is particularly vulnerable to the impacts of climate change as rising sea levels threaten to inundate its unique mangrove ecosystem (IPCC, 2002). Climate change is also expected to cause a sharp rise in soil and water salinity in the SRF (Agrawala et al., 2003). Since SRF’s natural vegetation regeneration is dependent on the salinity regime, climate change will change the vegetation composition, even if the forest avoids complete destruction (Ahmed et al., 1998). However, very little has been done to set up a continuous monitoring system to study vegetation change over time in the SRF (Akhter 2006). Previous forest inventories have been extensive and expensive, but accessibility issues and lack of funding have restricted the updating of forest vegetation maps after 1995 (Idem).
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CONTINUOUS CREATION IN THE PROBABILISTIC WORLD OF THE THEOLOGY OF CHANCE

CONTINUOUS CREATION IN THE PROBABILISTIC WORLD OF THE THEOLOGY OF CHANCE

by God at any subsequent moment t’ can itself determine (“decide”) to be F or non-F at t or t’. This process of partial self-determination could concern all substances created by God ex nihilo. It also seems to be possible that accidental properties of x which are produced by it at the irst moment of its existence can be replaced by other properties compatible with a given kind K produced by agents distinct from x and from God (say by y). But if x brings about that x is F at t, then x creates F ex nihilo. The reason for this is that if God creates x and God does not bring about F (or that x is F), then either x is doing it or another causal agent distinct from x and from God is doing it. Whatever that being could be, it would have to create F ex nihilo. This is impossible, because only God can do that. If x brings about that x is F at t’, then either the principle of divine control (at least in its unrestricted form: “all-form”) has to be rejected or x’s self-determination is an illusion. If this line of reasoning is correct, then all substances must be totally and directly determined (created and caused) by God. They must be determined by God “from the bottom up”. Therefore, it is metaphysically impossible that God created x and conserved it at the moment t’ and did not conserve all its essential and accidental properties at the moment t’.
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Evaluation of susceptibility of the ZRE1 alloy to hot cracking in conditions of forced strain

Evaluation of susceptibility of the ZRE1 alloy to hot cracking in conditions of forced strain

In order to evaluate the susceptibility to hot cracking in the high-temperature brittleness range, we have determined the changes of temperature of individual points when the alloy was cooled down from the solidus temperature. The tests were performed on the cylindrical Ø 10 x 120 mm specimens, using the Gleeble 3800 simulator, at Iron Metallurgy Institute in Gliwice. Four S-type thermocouples were pressure welded to the specimens: in the specimen axis and 2, 5 and 8 mm away from the axis. The specimens were fixed in copper holders, keeping a constant distance of 33 mm, and then were heated in the argon atmosphere at the 20 0 C/s rate to the temperature of liquid phase appearance, and were afterwards freely cooled. Changes in
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Introducing mapping standards in the quality assessment of buildings extracted from very high resolution satellite imagery

Introducing mapping standards in the quality assessment of buildings extracted from very high resolution satellite imagery

GEOBIA approaches applied to current and future VHR satellite imagery may expedite the acquisition and updating of spatial information, an increasing requirement in the municipal context. To assess if this goal is feasible and in which conditions, it is fun- damental to develop and implement quality assessment methods which are rigorous, objective, and that take in consideration the technical constraints of the large mapping scales traditionally used at the local level. Such a method could also contribute to increase the confidence and guide the use of spatial data sets obtained through this process. The present work represents an innovative approach to assess the quality of buildings extracted from VHR sa- tellite imagery using semi-automated methods through analysis of similarity with a reference database, taking place in the context of large scale mapping to assist urban planning in Portugal. A new ap- proach was developed and demonstrated to adopt technical map- ping standards in an object-based evaluation of different spatial quality elements. Automatic feature extraction software was employed to map buildings present in a pansharpened QuickBird image of Lisbon. The approach evaluates different aspects that determine overall quality of a single feature class map, namely the- matic quality, completeness, and geometric quality. These dimen- sions were evaluated using consecutive object-based tests and quantitative quality metrics were produced. Quality assessment was exhaustive (i.e., by census) and involved comparisons of ex- tracted features against a reference data set, introducing carto- graphic constraints from large scales used at municipal level, namely 1:1000, 1:5000, and 1:10,000. Although the approach was illustrated for buildings with red tile roofs, it could be applied to different building types and even to other polygon-based geo- graphic features present in topographic maps that could be subject to automatic feature extraction from remotely-sensed imagery.
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Contrasts in areas of rubber tree Clones in regard to soil and biomass Carbon stoCks

Contrasts in areas of rubber tree Clones in regard to soil and biomass Carbon stoCks

found that soil C levels in a 28-year-old rubber tree plantation were 20 % higher than those in a 15-year-old abandoned pasture, and 5 % lower than those found in a primary tropical forest. Despite these results, proper knowledge of potential C sequestration in soils and aboveground biomass under different rubber tree plantations is still distant, given that only a few studies have focused on it (Wauters et al., 2008; Maggioto et al., 2014). Such a gap is somewhat not in line with the Brazilian goal of replacing, by 2020, at least 28 % of its soils under degraded pastures by crops for profitable land use and which are considered as environmentally better in terms of potential C sequestration, above-and/or belowground (Strassburg et al., 2014).
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Mapping of sites in forest stands

Mapping of sites in forest stands

Generally, the forest companies use the total one year planting area as a minimum stratum of the total population and, consequently, the forest inventory processing has been conducted by applying the stratified random sampling to it. This study was carried out in the National Forest of Tres Barras, Brazil, and it aimed to classify and map the sites of Pinus elliottii stands. A systematic sampling was structured into clusters and applied independently by compartments. The clusters, in maltese cross, were composed of four sampling subunits, using Prodan sampling method with a fixed number of six trees. By analysis of the methodology it was possible to confirm the hypothesis: a) the selective thinning cause expressive increase of volumetric variability within compartments; b) the variation of sites within the compartments causes volumetric expansion of variance and this grows proportionally to the quality of the sites; c) the stratification in sites results in minimum variance within them; d) the stratification in sites resulted in until to 91% reduction of variances within them.
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Towards high resolution mapping of 3-D mesoscale dynamics from observations

Towards high resolution mapping of 3-D mesoscale dynamics from observations

In this framework, the first step in our work consisted of improving the existing MyOcean observation-based products (ARMOR3D, Guinehut et al., 2012) and in the development and testing of new high resolution horizontal interpolation and vertical extrapolation techniques (Buongiorno Nardelli, 2012; Buongiorno Nardelli et al., 2006; Buongiorno Nardelli and Santoleri, 2004, 2005), analysing the scales they are ef- fectively resolving. As a second step, a quasi-geostrophic (QG) diagnostic numerical model (the Q vector formulation of the omega equation) has been used to estimate the verti- cal velocities (Pascual et al., 2004; Ruiz et al., 2009). The omega equation was applied to different MyOcean products (both model and observation-based) in order to quantify the differences/limitations in the diagnostic tools used and the impact of the spatial resolution on the retrieved velocity. The results of these two steps are the subject of the present paper. It is worth noting that this work represents the first attempt to apply purely observation-based 3-D retrieval techniques at high resolution (also resolving mesoscale quasi-geostrophic dynamics) to obtain data that could be produced routinely within an operational system (namely from near real-time, freely available data, and potentially with global coverage). However, given the lack of independent (direct) measure- ments of the vertical velocities, a full validation of the new products is clearly not possible. Consequently, the approach followed here relies on the comparison between all the dif- ferent products, concentrating on a test case.
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An object-oriented approach for agrivultural land classification using rapideye imagery

An object-oriented approach for agrivultural land classification using rapideye imagery

With the improvement of remote sensing technology, the spatial, structural and texture information of land covers are present clearly in high resolution imagery, which enhances the ability of crop mapping. Since the satellite RapidEye was launched in 2009, high resolution multispectral imagery together with wide red edge band has been utilized in vegetation monitoring. Broad red edge band related vegetation indices improved land use classification and vegetation studies. RapidEye high resolution imagery acquired on May 29 and August 9th of 2012 was used in this study to evaluate the potential of red edge band in agricultural land cover/use mapping using an objected-oriented classification approach. A new object-oriented decision tree classifier was introduced in this study to map agricultural lands in the study area. Besides the five bands of RapidEye image, the vegetation indexes derived from spectral bands and the structural and texture features are utilized as inputs for agricultural land cover/use mapping in the study. The optimization of input features for classification by reducing redundant information improves the mapping precision over 9% for AdaTree. WL, and 5% for SVM, the accuracy is over 90% for both approaches. Time phase characteristic is much important in different agricultural lands, and it improves the classification accuracy 7% for AdaTree.WL and 6% for SVM.
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