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431.
Considering from point of view of the dynamics,it is convenient to regard the field to be predictedas a small disturbance superposed on the historical analogous field,and thus the statistical technique can beused in combining with the dynamics.Along this line,a coupled atmosphere-earth surface analogy-dynamicalmodel is formulated and applied to making monthly prediction.This approach facilitated the utility of the useful information contained in both the historical data setand the initial field to improve the dynamic model based solo on the latter and show better skill in prediction.  相似文献   
432.
A critical reappraisal of great historical interplate earthquakes in the occidental margin of South America, including southern Peru and northern Chile, is carried out.A spacetime distribution of the earthquakes associated to the seismotectonics regions defined by the rupture zones of the greatest events (1868, Mw = 8.8 and 1877, Mw = 8.8) is obtained. Both regions are seismic gaps that are in the maturity state of their respective earthquake cycles. The region associated to the 1868 earthquake presents a notable seismic quiescence in the present century.  相似文献   
433.
Surface rupture zone of historical earthquake is the most intuitive geomorphological response to fault activity. The rupture pattern, coseismic displacement and its geometric spatial distribution are important for determining segmentation and long-term movement behaviors of active fault. In the Barkol Basin of Xinjiang, according to the comprehensive result from remote sensing image interpretation, field surgery, high-resolution small unmanned aerial vehicles photography, terrain deformation measurements and trench excavation on geomorphological points, not only the new surface ruptures of the two M7 1/2 historical earthquakes in Barkol in 1842 and 1914 were found and defined between Xiongkuer and the southwest of Barkol County in southwestern part of the basin, but also the latest deformation evidence of the EW fold-up faults in the eastern part of the Basin was identified. Combined with the ancient document analysis of the two historical earthquakes, we finally conclude that the surface rupture zone in the western segment on the southern margin of the Barkol Basin is the seismogenic structure of the M7 1/2 earthquake in 1842. The surface rupture zone is mainly characterized by left-lateral strike-slip, roughly with en echelon arrangement spreading from Xiongkuer to the south of Barkol County. The length of the surface rupture zone determined by field investigation is at least about 65km, and the maximum horizontal displacement appears around the Xiongkuer Village. At the same time, the surface rupture zone gradually shows more significant thrust extrusion from west to east, and has a tendency of extension towards the central of the Barkol Basin. The average observed displacement of the entire surface rupture obtained by counting the coseismic offsets of multiple faulted gullies is(4.1±1.0)m, with the coseismic characteristic displacement of ~4m. The epicenter position should appear at the place with the largest horizontal dislocation amount near Xiongkuer Village. In addition, the length of the fold-blind fault zone in the vicinity of the Kuisu Town and the eastward extension to the Yanchi Township of the Yiwu Basin, which was discovered in the center of the Barkol Basin, is about 90km. The folded blind fault causes significant fold deformation in the latest sedimentary strata such as floodplain, and in addition, as shown on many outcrop sections, the bending-moment faults associated with the coseismic fold deformation have ruptured the surface. Therefore, the location of the epicenter should be located at the maximum fold deformation, which is near the Kuisu Town. The new research results not only further improve the understanding of the epicenter location and seismogenic faults of the two historical earthquakes in the Barkol Basin, but also provide an important reference for analyzing regional seismic hazards.  相似文献   
434.
BOOK REVIEWS     
Book Reviewed in this article: Development and Environment in Peninsular Malaysia . S. Robert Aiken, Colin H. Leigh, Thomas R. Leinbach, Michael R. Moss. The Rural-Urban Fringe: Canadian Perspectives . Ken B. Beesley and Lorne H. Russwurm, eds. Women and Development . Lourdes Benería, ed. The Border that Joins: Mexican Migrants and U.S. Responsibility . Peter G. Brown and Henry Shue, eds. Cities of the World: World Regional Urban Development . Stanley D. Brunn and Jack L. Williams, eds. Time Resources, Society, and Ecology: On the Capacity for Human Interaction in Space and Time (Vol. I, Preindustrial Societies). Tommy Carlstein. Urban Geography . David Clark. Spanish City Planning in North America . Dora P. Crouch, Daniel J. Garr, and Axel I. Mundigo. Not On Our Street: Community Attitudes to Mental Health Care . M. J. Dear and S. M. Taylor Unequal growth: Urban and Regional Employment Change in the U.K. Stephen Fothergill and Graham Gudgin. Agricultural Land in an Urban Society . Owen J. Furuseth and John T. Pierce. The Petroleum Industry in Oil-Importing Developing Countries . Fariborz Ghadar. Historical Understanding in Geography, An Idealist Approach . Leonard Guelke. Regional Planning in Europe . R. Hudson and J. R. Lewis, eds. Remote Sensing for Resource Management . Chris J. Johannsen and James L. Sanders, eds. Geography and The State . R. J. Johnston. Texas Graveyards: a Cultural Legacy . Tlrry G. Jordan. The Politics of Location: An Introduction . Andrew Kirby. A Social Geography of the City . David Ley. Energy and the Future . Douglas MacLean and Peter Brown, eds. The Natural Environment of Newfoundland Past and Present . A. G. Macpherson and J. B. Macpherson, eds. Tourism: Economic, Physical and Social Impacts . Alister Mathieson and Geoffrey Wall. Railroads and Land Grant Policy: A Study in Government Intervention . Lloyd J. Mercer. Progress in Rural Geography . Michael Pacione, ed. Progress in Urban Geography . Michael Pacione, ed. Models of Spatial Inequality: Settlement Patterns in Historical Archaeology . Robert Paynter. Natural Hazard Risk Assessment and Public Policy, Anticipating the Unexpected . William J. Petak and Arthur A. Atkisson. The Nature of Geomorphology . Alistair F. Pitty. Regional Conflict and National Policy . Kent A. Price Women and Spatial Change: Learning Resources for Social Science Courses . Arlene C. Rengert and Janice J. Monk, eds. Urban and Regional Analysis for Development Planning . Richard Rhoda. Rivers: Form and Process in Alluvial Channels . Keith Richards. This Remarkable Continent: An Atlas of United States and Canadian Society and Culture . John F. Rooney, Jr., Wilbur Zelinsky, and Dean R. Louder, gen. eds. The Origins of Open-Field Agriculture . Trevor Rowley, ed. Residential Location Determinants of the Older Population . Gundars Rudzitis. Borderland Sourcebook: A Guide to the Literature on Northern Mexico and the American Southwest . Ellwyn R. Stoddard, Richard L. Nostrand, and Jonathan P. West, eds. Arctic and Antarctic . David Sugden. Tall Timbers Ecology and Management Conference, February 22–24, 1979, Proceedings No. 16 . Graphic Communication and Design in Contemporary Cartography (Progress in Contemporary Cartography , Vol. II). D. R. Fraser Taylor, ed. Living with Energy Shortfall: A Future for American Towns and Cities . Jon Van Til. The United States: Habitation of Hope . J. Wreford Watson. Air Photo Interpretation for Archaeologists . D. R. Wilson. Urban and Rural Change in West Germany . Trevor Wild, ed. Population and Resources . Harry Robinson.  相似文献   
435.
介绍实验室计量认证工作,并介绍上海市测绘产品质量监督检验站按照GB/T15481-2000《检测和校准实验室能力的通用要求》(等同于ISO/IEC17025:1999)进行的质量体系文件转版工作。  相似文献   
436.
Data from European earthquakes in themagnitude range 5 to 8 between 1905 and1992 have been collected and collated, fordistances between 200 and 3400 km. The datainclude both analog and digital records,with priority on wave paths traversingnorthern Europe. Historical analog recordsfrom Uppsala and De Bilt have beendigitised, and appropriate responsefunctions established. New estimates ofseismic moments and moment magnitudes havebeen obtained, which together with momentmagnitudes from other sources have beencompared to surface wave magnitudes. Thelocation of the largest north Europeanearthquakes substantiate earliersuggestions that rifted regions (passivemargins, rifts and grabens) may have thelargest seismic potentials. Arandom-vibration (stochastic) model forprediction of observed peak amplitude,period and Fourier acceleration spectra hasbeen developed and calibrated againstintermediate and long-period observations.Reasonably good correspondence betweenpredictions and observations are obtainedwhen using a simple Brune source spectrum,new values for seismic moments andmoment-magnitude relations, together withreasonable assumptions for stress drop,geometrical spreading and anelasticattenuation. The model is useful first ofall for predicting broad regional averages,but as such it is robust, and it also hasthe potential to be used in an engineeringcontext for predicting spectral responseand peak ground accelerations. Some of theempirical data have also been studied interms of pseudo-relative spectral velocityand compared to strong-motion responsespectral prediction models established fornorthwestern Europe, again for lowfrequencies. Irrespective of these prediction models we emphasize, however, thatthe establishment of the data base itselfhas been an independent and importantpurpose of this study.  相似文献   
437.
卡尔·苏尔的文化生态学理论与实践   总被引:10,自引:0,他引:10  
邓辉 《地理研究》2003,22(5):625-634
“伯克利学派” ,又称“文化生态学派” ,是一个由卡尔·苏尔创立的、具有广泛学术影响的美国人文地理学派 ,在欧美地理学界和文化人类学界曾产生过巨大影响。本文对伯克利学派创始人卡尔·苏尔的学术思想和学术实践作了系统的分析和总结。苏尔的学术研究主要包括五个部分 :1 )农业起源问题研究 ;2 )文化景观与生态环境相互关系的研究 ;3)美洲探险史和发现史研究 ;4 )人类对自然环境的改造 ;5 )文化生态学方法论探索。指导苏尔学术实践活动的核心思想 ,是他在《景观的形态》和《历史地理学序言》中系统阐述和倡导的文化生态学思想 ,这就是强调文化景观与生态环境之间有机联系的分析 ,重视文化景观的发生学或历史地理学的研究  相似文献   
438.
An evaluation of the precision and resolution of the unspiked K–Ar dating method is presented with particular regard to the statistical significance of ages that are measured near or at the detection limit of the technique. Near-zero (historical) ages can be measured by the unspiked K–Ar technique with a precision that is essentially controlled by the precision with which the 40Ar/36Ar of the sample can be resolved from the present-day atmospheric value of 295.5. The best analytical precision on the isotopic ratio is ±0.05% (1σ) by this technique, which currently limits the lower detection limit of unspiked K–Ar ages to samples featuring at least 0.14% of radiogenic 40Ar. The corresponding youngest resolvable K–Ar age depends on the K content and atmospheric contamination of the sample. Total-fusion analysis of high-K refractory minerals like sanidine is not practicable via K–Ar, and the lowest resolvable age for medium-K samples more amenable to complete fusion is around 1.5 ka (on a single-run basis). It is argued that near-zero age measured with a probability density straddling or narrowing the time-origin cannot be handled without accounting for the non-negativity constraint imposed by the physical requirement of a positive age. The pertinent equations are derived both for the single-run case and for the case of independent replicates made on a single sample. We show that pooled K–Ar replicates can theoretically reduce the nominal uncertainty of individual unspiked ages (typically ±1.5 ka, 2σ) to a value that is close to the smallest 40Ar/39Ar isochron age uncertainty achievable on sanidine in the 0–2 ka range (±0.2 ka, 2σ). However, this performance is obtained at the cost of prohibitively large-sample statistics (n≥15) for medium-K feldspars datable via K–Ar. Coupled with the inability of the K–Ar approach to obviate the problems of excess/fractionated 40Ar and/or xenocrystic contamination, this makes the 40Ar/39Ar technique the method of choice for dating historical events by the K–Ar scheme.  相似文献   
439.
Landslides, debris flows and stream floods are common natural processes inNorthern Italy. Their occurrence can be correctly assessed in space and timeonly through a sound basis of knowledge acquired by the scientific use of alarge number of historical documents. Over the last 30 years, the CNR IRPIInstitute of Turin has made archive data utilisation one of its main points ofscientific research, through the collection of hundreds of thousands of recordscontained in published and unpublished documents and historical reports onnatural damaging events over the last 500 years, particularly since XIX Century.The historical data, interpreted and selected on a scientific basis, have beenorganised in a database and utilised for landscape planning and hydrogeologicalprevention. In co-operation with public organisations, the IRPI Institute hassupplied information (type, location, magnitude, frequency and effects) abouthazardous events in Northern Italy. To give an example, in the last 4 yearsabout 4,500 failure events have been detected along the road network of theTurin Province and many debris flow, rockfall, landslide and flood events inthe Lombardy Region. These data are reported as points linked to the relevantevent-card on technical cartography (scale 1:10,000 or 1:25,000), so that theycan be immediately utilised either on paper or digitally (e.g., GIS, Arcview software).The present day elaboration of archival data permit the possible analytical applications for structural interventions in natural hazard remediation in built-up areas. In all cases, the results of research allow public awareness of natural danger and the correct layout of civil protection strategies.  相似文献   
440.
城市历史地区保护对城市规划学科的渗透越来越广泛深入,并且随着城市的发展,有关保护观念、方法、内容等在不断发生变化。对于变化中的城市历史地区保护规划,本文从宏观层面归纳总结了保护方式、保护目标、保护内容以及与城市总体发展密切相关的城市土地利用、空间结构、交通道路等重要方面可深入细化的内容。  相似文献   
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