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Floods in Malaysia have been increasing in frequency and magnitude as reflected in the Kelantan Flood event in 2014 that resulted in a huge loss of lives and properties. Whereas remote sensing (RS) and geographical information system (GIS) tools have been extensively applied in flood disaster management, there are few reports and studies on the impact of floods on the land use/land cover environment in a post-disaster assessment. In this study, an integrated modelling approach was developed that used Landsat 8 OLI TIRS (Operational Land Imager (OLI) and Thermal Infrared Sensor) data, flood indexing and classification processes to estimate the impact of flood on the environment. The Normalized Difference Flood Index-3 (NDFI3) is an improvement on NDFI2 that takes into account the effects of cloud shadow in the images when extracting flood index areas. The flood model developed showed good agreement when compared with flooded areas shown in SAR (synthetic-aperture radar) image. The results of the flood extent as a proxy for damage estimation showed that the total flooded area was 502.34 km2 for the Kelantan Flood event in 2014, with plantation and built-up area accounting for 43 and 34.6% respectively. The least affected land uses/land covers were deforested area and forest, which accounted for 12.2 and 10.2% respectively. The RS and GIS technique developed in this post-disaster damage assessment is effective, relatively inexpensive and simple to implement by local authorities in support of post-flood disaster planning and decision-making.  相似文献   
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The connections between malaria incidence and climate variability have been studied in recent time using some mathematical and statistical models. Many of the statistical models in literature focused on time series approach based on Box–Jenkins methodology. However, fitting time series model based on the Box–Jenkins methodology may be challenging. Most malaria incidence data are count and are over-dispersed. In this study, negative binomial models were formulated for fitting malaria incidence in Akure—one of the epidemic cities in Nigeria. In particular, negative binomial models were formulated for each of the number of outpatient individuals, number of inpatient individuals and mortality count as a function of some climate variables. It was found that an increase in minimum temperature and relative humidity at lag 1 significantly increased the chance of malaria transmission and thereby leads to an increase in the number of inpatient and outpatient individuals, as well as the total number of malaria cases. The minimum temperature, rainfall amount and relative humidity of the study area have a significant impact on the increase of number of inpatient and outpatient individuals while mortality count depends on the total number of reported malaria cases. The findings from this study is to offer in-depth understanding on climate-malaria incidence linkages in Akure, Nigeria.

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Acta Geochimica - The distribution and geochemical significance of dibenzofurans, phenyldibenzofurans and benzo[b]napthofurans in source rocks from Niger Delta basin, Nigeria, were investigated by...  相似文献   
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Geotechnical and Geological Engineering - Historically, the idea of designing and installing rockbolts in rockmasses can be traced back to the construction of the Snowy Mountain hydroelectric...  相似文献   
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Geotechnical and Geological Engineering - Empirical relationships for estimating Uniaxial Compressive Strength (UCS) of rock from other rock properties are numerous in literature. This is because...  相似文献   
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Modeling the impacts of reforestation on future climate in West Africa   总被引:1,自引:0,他引:1  
This study investigates the potential impacts of reforestation in West Africa on the projected regional climate in the near two decades (2031–2050) under the SRES A1B scenario. A regional climate model (RegCM3) forced with a global circulation model (ECHAM5) simulations was used for the study. The study evaluates the capability of the regional model in simulating the present-day climate over West Africa, projects the future climate over the region and investigates impacts of seven hypothetical reforestation options on the projected future climate. Three of these reforestation options assume zonal reforestation over West Africa (i.e., over the Sahel, Savanna and Guinea), while the other four assume random reforestation over Nigeria. With the elevated GHGs (A1B scenario), a warmer and drier climate is projected over West Africa in 2031–2050. The maximum warming (+2.5°C) and drying (?2?mm?day?1) occur in the western part of the Sahel because the West Africa Monsoon (WAM) flow is stronger and deflects the cool moist air more eastward, thereby lowering the warming and drying in the eastern part. In the simulations, reforestation reduces the projected warming and drying over the reforested zones but increases them outside the zones because it influences the northward progression of WAM in summer. It reduces the speed of the flow by weakening the temperature gradient that drives the flow and by increasing the surface drag on the flow over the reforested zone. Hence, in summer, the reforestation delays the onset of monsoon flow in transporting cool moist air over the area located downwind of the reforested zone, consequently enhancing the projected warming and drying over the area. The impact of reforesting Nigeria is not limited to the country; while it lowers the warming over part of the country (and over Togo), it increases the warming over Chad and Cameroon. This study, therefore, suggests that using reforestation to mitigate the projected future climate change in West Africa could have both positive and negative impacts on the regional climate, reducing temperature in some places and increasing it in others. Hence, reforestation in West Africa requires a mutual agreement among the West African nations because the impacts of reforestation do not recognize political boundaries.  相似文献   
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Acta Geotechnica - In the original publication of the article, the left-hand side of Eq. (8) had been mistakenly changed.  相似文献   
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