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1.
In this study, a novel Bayesian semiparametric structural additive regression (STAR) model is introduced in multi-city time series air pollution and human health studies. This modeling approach can simultaneously take into account the fixed effects, random effects, nonlinear smoothing functions and spatial functions in an integrated model framework. This study focuses on examining the powerful functionalities of this approach in modeling air pollution and mortality data of 100 U.S. cities from 1987 to 2000. Compared with previous studies, the modeling approach used in this study yields consistent findings of nation-level and city-level PM10 (particulate matter less than 10?μm) effects on mortality. Notably, cities with significantly elevated mortality rates were concentrated in the Northeastern U.S. This modeling approach also emphasizes the important functionality of the spatial function in visualizing disease mapping. Model diagnostics were performed to confirm the availability of the STAR model. We also found consistent findings by using different hyperparameters in the sensitivity analysis. To sum up, the implementation of this modeling approach has achieved the goals of applying a spatial function and obtaining robust results in the multi-city time series air pollution and human health study.  相似文献   
2.
In July, heating of the continents in the Northern Hemisphere results in strengthened monsoon systems which bring rains to West Africa. In Nigeria, the annual rainfall total decreases from over 3,800 mm at Forcados on the coast to under 650 mm at Maiduguri in the north-east of the country. June, July, August and September are the rainiest months throughout the country. In many parts of the south, however, there is “supposed to be” a slight break in the rains for some 2 to 3 weeks in late July and early August or the so called “August break”. In this study, we are underscoring the obvious that climate is changing. The daily series of rainfall data for 1983–2003 analyzed between the months of July–August for some sites in the Eastern humid zone of Southern Nigeria shows that the “August break” may indeed “be breaking”. We have discussed some practical approaches to climate change research in this monsoon region.  相似文献   
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Rural societies in low-income, high-population countries often faces scarcity of water of suitable quality for domestic use and agriculture. Hydrogeologists should therefore orientate their research work towards solving practical problems and impart basic knowledge about the hydrogeology of local watersheds to the village councils and communities so as to ensure their participation in better management of groundwater resources. Such cooperation between the hydrogeologists and villagers is the foundation of socio-hydrogeology, which aims at broader dissemination of information and discussions with hydrogeologists at village meetings regarding watershed management such as recharge augmentation, groundwater quality issues and prudent use of groundwater. Socio-hydrogeology implies improved accessibility of rural society to hydrogeological experts and better communication through the use of more appropriate and understandable language.  相似文献   
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Geoelectrical resistivity investigation using Vertical Electrical Sounding (VES) technique was conducted at Port Blair, South Andaman Island, to locate the fractures in different formations and to decipher its groundwater potential. A total of 40 VES were carried out covering the entire study area using Schlumberger electrode configuration out of which 34 VES fall in Andaman Flysch formations and the remaining VES in Ophiolite formations. The interpreted resistivity results were integrated with nine borehole lithologs for the subsurface analysis. The combination of VES with borehole litholog data has provided a close correspondence on subsurface hydrogeological conditions. The interpreted VES data of various formations showed drastic variations in the resistivity ranging from higher in Ophiolite, moderate in Andaman Flysch and very low in valleys of Andaman Flysch formations. The study further revealed that the weathered and fractured volcanics of Ophiolite groups of rocks and sandstone that occur in the Andaman Flysch formations constitute the productive water bearing zones categorized as good groundwater potential zone. Based on the geoelectrical parameters, viz., thickness of layers and the layer resistivity values, a groundwater potential map was prepared, in which good, moderate, and poor groundwater zones were demarcated. Further, numerical, spatial and litho-geoelectric models of resistivity were analyzed in terms of groundwater potential and these models have thus enabled to prepare a comprehensive groundwater development and management plans proving its efficacy in this art of exploratory investigations.  相似文献   
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Ocean Dynamics - Response of Ganga-Brahmaputra river plume to wind forcing in the Bay of Bengal is studied using a numerical ocean circulation model. Four different wind forcing scenarios, namely,...  相似文献   
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Population increases, land-use changes and marketing opportunities are important factors affecting crop-livestock integration particularly with respect to their effect on soil fertility and feed supply for ruminant livestock. As the human population density rises, crop farmers and grazers are finding it profitable to establish contracts for paddocking, and they are reaching agreement on equitable ways to make use of crop residues and take care of livestocks. As the processes of intensification proceed, mixed crop-livestock systems are evolving as the viable and dominant farming system, allowing smallholder farmers to capitalize on the complementarity between crops and livestock. Strategies directed to raise the productivity of specific crop-livestock systems need to consider the stage of development of the target area in relation to intensification and the nature of crop-livestock interactions. Information related to crop and livestock systems in West Africa is currently available from various sources e.g., household surveys, aerial surveys, rural appraisal, experimental etc., and held by different agencies. The approach used in this study shows how such data (biophysical and socioeconomic) can be integrated within a GIS environment and synthesized to identify the evolution of systems across environments and also to identify constraints and potential of the systems. Potential for integrated crop-livestock systems remains untapped and/or knowledge of its existence is unknown for large parts of Nigeria. Using data from 36 case studies and georeferenced data on cropping intensities and livestock population for the entire country, it was possible to predict emerging crop-livestock systems using GIS. Indeed, depending on availability of data, it is now possible to extend a similar approach in other African countries. The potential contribution of this technology is largely unknown in West and Central Africa, where few operational programs use them. Major technological innovations and appropriate government policies have potential to shift the balance in regional developments, if targeted carefully at areas where the right conditions exist. Further research could then target specific areas thus ensuring efficient allocation of resources while policy makers can achieve development goals by directing policies and resources to domains that have the greatest potential. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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