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921.
江苏海岸线演变趋势遥感分析 总被引:16,自引:4,他引:16
数千年来,海岸线的摆动使江苏省东部经历了“沧海桑田”的变化,海岸线的进退都会给沿海人们的生存和发展带来直接影响。作者利用3期卫星遥感图像资料对江苏海岸线20a来的演变特点和趋势作了定量和定性的分析。根据史料,对历史岸线作了概略地分析,同时对岸线的稳定性进行了划分。 相似文献
922.
923.
傅华 《沙漠与绿洲气象(新疆气象)》2002,25(4):23-25
介绍了新疆1:2000万基础地理信息在MAPGIS中的研建过程和技术方法,将气象卫星(NOAA)、地球观测卫星(EOS)的遥感产品专题图与地理信息镶嵌配准,并且分别建立在1:200万和1:100万基础工作平台上。 相似文献
924.
地质灾害遥感调查的应用前景 总被引:15,自引:0,他引:15
地质灾害遥感调查正由示范性实验阶段步入全面推广的实用性阶段。遥感技术及与之相关的高新技术的飞速发展,已使地质灾害遥感调查成为可能。遥感技术可以贯穿于地质灾害调查、监测、预警、评估的全过程,能适应突发性地质灾害救灾工作的时效性要求,因而具有广阔的应用前景。 相似文献
925.
西藏定结幅区调工作中的断裂构造遥感研究方法探讨 总被引:1,自引:0,他引:1
西藏定结地区地质构造背景复杂、型式多样,对包括变质核杂岩在内的断裂构造的研究是该地区构造解析的重点内容。在该地区有效地运用遥感技术来辅助野外实地调查十分必要。本文从信息提取、光谱特征分析、空间结构分析等几个方面探讨了在该地区运用遥感技术进行断裂构造研究的工作方法。另外,针对定结幅ETM+影像的实际情况,分别介绍了冰雪覆盖下的地物弱信息提取和高山地区地形影响的消除及三维信息恢复等图像处理方法。 相似文献
926.
遥感影像信息在活动断裂研究中的应用 总被引:11,自引:0,他引:11
遥感图像不仅从宏观上展现了活动断裂与其它活动构造的影像全貌,而且直观地揭示了洗断裂的影像信息,为分析断裂的活动状态及其与地震活动的相关性,为识别地震构造与强震的孕育地段提供了丰富的信息。而遥感技术方法本身的优势,又使得遥感构造研究具有了视域开阔、信息丰富直观、处理方法多样、易于综合分析、获取成果迅速等特点。从直观上讲,活动断裂遥感影像标志主要有色调、构造形态、断层三角面、地貌及水系等几个方面,归纳起来主要是垂直错动标志。从多方面总结了活动断裂在遥感影像上的表现特征和识别标志,并为今后活动断裂以及地震研究中遥感影像信息的应用提出了一些有效方法和途径。 相似文献
927.
Estimation of colored dissolved organic matter and salinity fields in case 2 waters using SeaWiFS: Examples from Florida Bay and Florida Shelf 总被引:1,自引:0,他引:1
E. J. D’Sa C. Hu F. E. Muller-Karger K. L. Carder 《Journal of Earth System Science》2002,111(3):197-207
Estimates of water quality variables such as chlorophylla concentration (Chl), colored dissolved organic matter (CDOM), or salinity from satellite sensors are of great interest to
resource managers monitoring coastal regions such as the Florida Bay and the Florida Shelf. However, accurate estimates of
these variables using standard ocean color algorithms have been difficult due to the complex nature of the light field in
these environments. In this study, we process SeaWiFS satellite data using two recently developed algorithms; one for atmospheric
correction and the other a semianalytic bio-optical algorithm and compare the results with standard SeaWiFS algorithms. Overall,
the two algorithms produced more realistic estimates of Chl and CDOM distributions in Florida Shelf and Bay waters. Estimates
of surface salinity were obtained from the CDOM absorption field assuming a conservative mixing behavior of these waters.
A comparison of SeaWiFS-derived Chl and CDOM absorption with field measurements in the Florida Bay indicated that although
well correlated, CDOM was underestimated, while Chl was overestimated. Bottom reflectance appeared to affect these estimates
at the shallow central Bay stations during the winter. These results demonstrate the need for new bio-optical algorithms or
tuning of the parameters used in the bio-optical algorithm for local conditions encountered in the Bay. 相似文献
928.
929.
V. Puygrenier F. Lohou B. Campistron F. Saïd G. Pigeon B. Bnech D. Sera 《Atmospheric Research》2005,74(1-4):329-353
Surface and remote-sensing instruments deployed during ESCOMPTE experiment over the Marseille area, along the Mediterranean coast, were used to investigate the fine structure of the atmospheric boundary layer (ABL) during sea-breeze circulation in relation to pollutant transport and diffusion. Six sea-breeze events are analyzed with a particular focus on 25 June 2001.Advection of cool and humid marine air over land has a profound influence on the daytime ABL characteristics. This impact decreases rapidly with the inland distance from the sea. Nearby the coast (3 km inland), the mixing height Zi rises up to 750 m and falls down after 15:00 (UT) when the breeze flow reaches its maximum intensity. A more classical evolution of the ABL is observed at only 11-km inland where Zi culminates in the morning and stabilizes in the afternoon at about 1000 m height.Fine inspection of the data revealed an oscillation of the sea-breeze with a period about 2 h 47 min. This feature, clearly discernable for 3 days at least, is present in several atmospheric variables such as wind, temperature, not only at the ground but also aloft in the ABL as observed by sodar/RASS and UHF wind profilers. In particular, the mixing height Zi deduced from UHF profilers observations is affected also by the same periodicity. This pulsated sea-breeze is observed principally above Marseille and, at the northern and eastern shores of the Berre pond.In summary, the periodic intrusion over land of cool marine air modifies the structure of the ABL in the vicinity of the coast from the point of view of stability, turbulent motions and pollutants concentration. An explanation of the source of this pulsated sea-breeze is suggested. 相似文献
930.
Geometry and growth of an inner rift fault pattern: the Kino Sogo Fault Belt, Turkana Rift (North Kenya) 总被引:1,自引:0,他引:1
A quantitative analysis is presented of the scaling properties of faults within the exceptionally well-exposed Kino Sogo Fault Belt (KSFB) from the eastern part of the 200-km-wide Turkana rift, Northern Kenya. The KSFB comprises a series of horsts and grabens within an arcuate 40-km-wide zone that dissects Miocene–Pliocene lavas overlying an earlier asymmetric fault block. The fault belt is 150 km long and is bounded to the north and south by transverse (N50°E and N140°E) fault zones. An unusual feature of the fault system is that it accommodates very low strains (<1%) and since it is no older than 3 Ma, it could be characterised by extension rates and strain rates that are as low as 0.1 mm/yr and 10−16 s−1, respectively. Despite its immaturity, the fault system comprises segmented fault arrays with lengths of up to 40 km, with individual fault segments ranging up to 9 km in length. Fault length distributions subscribe to a negative exponential scaling law, as opposed to the power law scaling typical of other fault systems. The relatively long faults and segments are, however, characterised by maximum throws of no more than 100 m, providing displacement/length ratios that are significantly below those of other fault systems. The under-displaced nature of the fault system is attributed to early stage rapid fault propagation possibly arising from reactivation of earlier underlying basement fabrics/faults or magmatic-related fractures. Combined with the structural control exercised by pre-existing transverse structures, the KSFB demonstrates the strong influence of older structures on rift fault system growth and the relatively rapid development of under-displaced fault geometries at low strains. 相似文献