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61.
ABSTRACT

Climate patterns, including rainfall prediction, is one of the most complex problems for hydrologist. It is inherited by its natural and stochastic phenomena. In this study, a new approach for rainfall time series forecasting is introduced based on the integration of three stochastic modelling methods, including the seasonal differencing, seasonal standardization and spectral analysis, associated with the genetic algorithm (GA). This approach is specially tailored to eradicate the periodic pattern effects notable on the rainfall time series stationarity behaviour. Two different climates are selected to evaluate the proposed methodology, in tropical and semi-arid regions (Malaysia and Iraq). The results show that the predictive model registered an acceptable result for the forecasting of rainfall for both the investigated regions. The attained determination coefficient (R2) for the investigated stations was approx. 0.91, 0.90 and 0.089 for Mosul, Baghdad and Basrah (Iraq), and 0.80, 0.87 and 0.94 for Selangor, Negeri Sembilan and Johor (Malaysia).  相似文献   
62.
63.
It is shown that available optical and ultraviolet data relating to the interstellar dust are elegantly explained on the basis of a modified microbal grain model. A model comprised of two biologically derived components, modified under interstellar conditions. Data on interstellar extinction, albedo and polarization may be accounted for by this model.  相似文献   
64.
Natural Resources Research - In surface mines and underground excavations, every blasting operation can have some destructive environmental impacts, among which air overpressure (AOp) is of major...  相似文献   
65.
This paper analyses the urban process in the oil producing countries of the Gulf. The mode of urbanization is identified as one characterized by an extreme case of primacy but with rates varying among the countries of the region. This pattern is related to the historical evolution of human settlements as affected by the local environmental qualities and the recent large scale development of urban infrastructures which favoured the already existing capital cities. The relative city growth rates are among the highest in the world but with a declining tendency which reflects expenditure patterns and the nature of the regional economies. The high growth rates are essentially due to massive foreign migration into the region and to extremely high natural increase rate — an abnormal condition in an urban process approaching saturation point. The role of these primate centres in the development of the region is undeniable and, furthermore, all indications suggest that this pattern of urban development will continue in the furture as it is, perhaps economically and politically less costly.  相似文献   
66.
Noise and an abnormal distributed-image histogram is the main challenge of using SAR data. From this point of view, this study’s authors motivated the non-use of user-defined input parameters. To achieve this purpose, a fuzzy approach was proposed to extract shoreline from SENTINEL-1A data. The parameters in the processing of the SENTINEL-1A image were generated automatically with LIDAR-intensity-derived object-based segmentation results. The LIDAR-intensity image was segmented with the Mean-shift method. The corresponding result was used to estimate the input parameters for fuzzy clustering of the SENTINEL-1A image. Fuzzy segmentation was proposed, due to the expected large number of values regarding water and land classes except for the pixels along the shoreline. The memberships for land and water classes were separately computed. In the proposed approach, the results from LIDAR and SENTINEL-1A dataset are promising, with differences below 1 pixel (10?m) by evaluation with the used reference vector data.  相似文献   
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