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202.
203.
模糊信息优化处理方法在陕西泾阳南塬塬边斜坡稳定性区划中的应用 总被引:1,自引:0,他引:1
结合野外调查,应用模糊信息优化处理方法对泾阳南塬塬边斜坡各评价单元进行了评价,最后根据评价结果将塬边斜坡进行了稳定性区划. 相似文献
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205.
基于小波分析的声发射信号处理 总被引:4,自引:0,他引:4
小波分析作为一种新的信号分析处理方法,可对任意信号,信号的任一时刻、任一频段进行时频分析。将小波分析用于声发射信号处理,有助于声发射技术的发展与推广应用。 相似文献
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不同的温度参数数据处理方法有不同的计算结果,本文针对检测与评定气候环境试验设备的技术性能中存在的问题,分析了三个标准(GB 11158-89、GB/T 5170.1-1995、JTM K 05-1991)的温度参数数据处理方法,比对了二组实际检测数据的计算结果,说明"绝对极值法"科学准确、简捷实用. 相似文献
209.
Many technologies in precision agriculture (PA) require image analysis and image- processing with weed and background differentiations.
The detection of weeds on mulched cropland is one important image-processing task for sensor based precision herbicide applications.
The article introduces a special vegetation index, the Difference Index with Red Threshold (DIRT), for the weed detection
on mulched croplands. Experimental investigations in weed detection on mulched areas point out that the DIRT performs better
than the Normalized Difference Vegetation Index (NDVI). The result of the evaluation with four different decision criteria
indicate, that the new DIRT gives the highest reliability in weed/background differentiation on mulched areas. While using
the same spectral bands (infrared and red) as the NDVI, the new DIRT is more suitable for weed detection than the other vegetation
indices and requires only a small amount of additional calculation power. The new vegetation index DIRT was tested on mulched
areas during automatic ratings with a special weed camera system. The test results compare the new DIRT and three other decision
criteria: the difference between infrared and red intensity (Diff), the soil-adjusted quotient between infrared and red intensity
(Quotient) and the NDVI. The decision criteria were compared with the definition of a worse case decision quality parameter
Q, suitable for mulched croplands. Although this new index DIRT needs further testing, the index seems to be a good decision
criterion for the weed detection on mulched areas and should also be useful for other image processing applications in precision
agriculture.
The weed detection hardware and the PC program for the weed image processing were developed with funds from the German Federal
Ministry of Education and Research (BMBF). 相似文献
210.
Managers need measurements and resource managers need the length/width of a variety of items including that of animals, logs,
streams, plant canopies, man-made objects, riparian habitat, vegetation patches and other things important in resource monitoring
and land inspection. These types of measurements can now be easily and accurately obtained from very large scale aerial (VLSA)
imagery having spatial resolutions as fine as 1 millimeter per pixel by using the three new software programs described here.
VLSA images have small fields of view and are used for intermittent sampling across extensive landscapes. Pixel-coverage among
images is influenced by small changes in airplane altitude above ground level (AGL) and orientation relative to the ground,
as well as by changes in topography. These factors affect the object-to-camera distance used for image-resolution calculations.
‘ImageMeasurement’ offers a user-friendly interface for accounting for pixel-coverage variation among images by utilizing
a database. ‘LaserLOG’ records and displays airplane altitude AGL measured from a high frequency laser rangefinder, and displays
the vertical velocity. ‘Merge’ sorts through large amounts of data generated by LaserLOG and matches precise airplane altitudes
with camera trigger times for input to the ImageMeasurement database. We discuss application of these tools, including error
estimates. We found measurements from aerial images (collection resolution: 5–26 mm/pixel as projected on the ground) using
ImageMeasurement, LaserLOG, and Merge, were accurate to centimeters with an error less than 10%. We recommend these software packages as a means for expanding
the utility of aerial image data. 相似文献