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41.
Nowadays, detecting and interpreting random variation extracted from satellite image time series is a far-reaching real-world issue. A more adequate approach should be designed to deal with this challenge. In this paper, we propose an efficient knowledge-based approach for vegetation monitoring using normalized derivation vegetation index time series. First, a decomposition process is designed to separate seasonal, trend and remainder components. Then, a genetic based schema is proposed to generate association rules. The extracted knowledge is intended to interpret the remainder component extracted during the previous phase by discovering the hidden link between random variation and climate observations. For validation purpose, a database covering the regions in Northwestern Tunisia is used for a period starting from 2000 to 2012. The data have been derived from Moderate resolution Imaging Spectroradiometer and fused with ground climate data (temperature and precipitation) in the form of fuzzy association rules. The obtained results show the efficiency of the proposed approach by reducing the non-stationarity effect.  相似文献   
42.
Astronomy Reports - In this work, we have revealed a new model emerged from the restricted three-body problem within a framework of a non-isotropic variation of mass. This variation is taken when...  相似文献   
43.
Numerical simulations of unsaturated solute transport from point sources were carried out using HYDRUS-1D. Three different soil types cropped with spring wheat were considered at three different locations in Sweden: Malmö, Norrköping and Petisträsk. Two types of rainfall data were used, point-scale raingauge measurements and a gauge-adjusted weather radar product at four spatial resolutions, 2 × 2, 6 × 6, 10 × 10 and 14 × 14 km2. The results showed that differences in the mean solute transport depths were small and not significant, with the exception of Petisträsk. Maximum transport depths were in most cases significantly larger using raingauge data compared to radar data. The results showed that using areal-averaged rainfall input will give solute transport estimations close to those using point-measured data. This shows the great potential in using radar-measured rainfall data in small-scale hydrological applications.  相似文献   
44.
The presence of uniform orientation patterns of pseudowollastonite indicates a uniform and slow increase of temperature in the furnaces used in the production of the 16th-century Iznik ceramics. Determination of pseudowollastonite in rounded pores (d = 20–40 μm) in the glaze probably indicates formation of vapor phases in pores. © 1993 John Wiley & Sons, Inc.  相似文献   
45.
Role of stochastic forcing in ENSO in observations and a coupled GCM   总被引:2,自引:0,他引:2  
A procedure is presented to estimate the role of atmospheric stochastic forcing (SF) in El Ni?o–Southern Oscillation (ENSO) simulated by a coupled ocean–atmosphere general circulation model (CGCM), in direct comparison to observations represented by a global reanalysis product. SF is extracted from the CGCM and reanalysis as surface wind anomalies linearly independent of the sea-surface temperature anomalies. Madden–Julian Oscillation (MJO) is isolated from SF to quantify its role in ENSO. A coupled ocean–atmosphere model of intermediate complexity is forced with SF, as well as its MJO and non-MJO components, from the reanalysis and CGCM. The role of SF is estimated by comparing the original ENSO in observations and the CGCM with that reproduced by the intermediate model. ENSO statistics in both reanalysis and CGCM are better reproduced when the intermediate model is tuned to be weakly stable than unstable. The intermediate model driven by SF from the reanalysis reproduces most characteristics of observed ENSO, such as its spectrum, seasonal phase-locking, fast decorrelation of ENSO SST during boreal spring, and its lag-correlation with SF. In contrast, not all characteristics of ENSO in the CGCM are reproduced by the intermediate model when SF from the CGCM is used. The seasonal phase-locking of ENSO in the CGCM is not reproduced at all. ENSO, therefore, appears to be driven by SF to a lesser degree in the CGCM than in observations. Characteristics of observed ENSO reproduced by the intermediate model (driven by SF) can be largely attributed to the MJO; which, for instance, is responsible for the fast decorrelation of ENSO SST during boreal spring in both reanalysis and CGCM. The non-MJO component seems to be more responsible than the MJO for erroneous features of ENSO in the CGCM.  相似文献   
46.
The present study reveals spatial variability of haloacetic acids and the basic physiochemical properties of drinking water samples through visualization based on the Kriging algorithm and hierarchical cluster analysis. Both projection and statistical method contributed to the logical classification of the indoor and outdoor water samples collected from various governorates covering more than 95% of the residential areas in Kuwait. Clustering of the variables led to the formation of several significant clusters corresponding to the effect of chlorine concentration and its residence time on the formation potential of chlorinated acetic acid derivatives in desalinated drinking water as well as to the total ionic composition of water samples and to the effect of the formation of brominated acetic acid derivatives. Clustering of samples, both indoor and outdoor, indicated that all of governorates located in the northern part of Kuwait are supplied with water containing high concentrations of chlorinated acetic acid derivatives, whereas significantly lower amounts of chlorinated or monobrominated acetic acids were found in water samples in the central and southern parts of the country.  相似文献   
47.
Three hundred and twenty‐two samples of desalinated household water were collected from 99 sampling locations that covered 95% of Kuwaiti's residential areas. Seventy‐one brands of bottled water were collected from Kuwaiti markets. The water quality parameters that were studied included pH, electrical conductivity (EC), total dissolved solids (TDS), F?, Cl?, Br?, , , , , , , , and the major macronutrients Na+, K+, Ca2+, and Mg2+. The analysis yielded a large range of results for most of these parameters, with differences in some cases exceeding 10‐fold. With a few exceptions, the results were found to comply with US‐EPA and WHO standards. Only the water in two brands of bottled water was acidic (pH < 6.5). The TDS was found to be higher than the US‐EPA regulated value in 4 and 3% of the household samples and bottled water brands, respectively. The fluoride levels were generally higher in bottled water than in household water. However, the household water that was produced by the Doha desalination plant and some of the European brands of bottled water were the best samples studied in terms of their quantity of Ca2+, Mg2+, and Na+ compared with the DRI values for those substances. EC and TDS were positively correlated with , , Na+, K+, Ca2+, and Mg2+ for household water but only with Ca2+ and Mg2+ for bottled water.  相似文献   
48.
The hydrodynamic equations of positive and negative dust, Boltzmann electron and ion density distribution, and Poisson equation are used along with the reductive perturbation method to derive a cylindrical Kadomtsev-Petviashvili (CKP) equation. G′/G expansion method is used to obtain a new class of solutions. At certain condition, the solutions degenerate to solitary wave solutions. The effects of the physical parameters on the characteristics of solitary pulses are examined. The results give elucidation of the properties of dust acoustic solitary pulses in multicomponent space plasmas, particularly in interstellar dust clouds in a galactic disk and astrophysical plasma systems.  相似文献   
49.
50.
The shallow subsurface structures of the offshore Nile Delta particularly in the southeastern Mediterranean were dealt through the interpretation of 40 two-dimensional seismic reflection lines. The interpretations of seismic reflection data indicated that the principle sedimentary processes affecting the study area include three main structural groups according to their origin and development. The first group of structures comprises of gravity-driven structures, which include slides, slumps, turbidities, and debris flow. Slides are present in three different forms on seismic sections: slide sheets, slides with scar, and wedges of slide materials. Slumps have many geometrical shapes: lenses, spoon-shaped slumps, and slumped blocks bound by growth faults. Debris flows are present as transparent unit (due to the dispersion of seismic waves at debris boundaries), whereas turbidities appear on the seismic profiles, which are formed of closely spaced parallel thin reflectors analogous to their thin stratified bedded layers. The second group of structures is syn-depositional structures, which include growth faults, and tilted and rotated fault blocks. Growth faults are listric in shape and usually dip seaward; displacements along the fault plane increase with depth. Some of these faults are incipient, and some are complicated and intersected by secondary antithetic faults. Most of the growth faults soles out basin wards and in the evaporites layer. Fault blocks are formed due to the Messinian evaporite movement vertically and horizontally due to its mobility as a consequence to the pressure resulted from the overloading of Pliocene sediment. The third group of structures comprises evaporite flow structures such as diapiric structures and graben collapse structures. The surface of the Messinian evaporites was folded during its flow as a consequence to the lateral compression acted on the mobile strata of the Messinian evaporites to form diapiric triangular structures and creates a stress zone faulting and fractures system. These conditions led to the formation of collapse structures or graben collapse structures.  相似文献   
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