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1.
Kiacatoo Man, a large, rugged Aboriginal adult buried in the Lachlan riverine plains of southeastern Australia, was discovered in 2011. Laser‐ablation uranium series analysis on bone yielded a minimum age for the burial of 27.4 ± 0.4 ka (2σ). Single‐grain, optically stimulated luminescence ages on quartz sediment in which the grave had been dug gave a weighted mean age of 26.4 ± 1.5 ka (1σ). Luminescence samples from the grave infill and from sediment beneath the grave exhibit overdispersed dose distributions consistent with bioturbation or other disturbance, which has obscured the burial signal. The overlap between the minimum (U‐series) and maximum (luminescence) ages places the burial between 27.0 and 29.4 ka (2σ). Luminescence ages obtained from the channel belt of between 28 ± 2 and 25 ± 3 ka indicate that fluvial sedimentation was occurring before the Last Glacial Maximum, which is consistent with the broader geomorphic setting. Together, these results are internally and regionally consistent, and indicate that Kiacatoo Man was one of the more ancient individuals so far identified in Australia. His remains are important to our understanding of patterns of biological variation and other processes that have shaped people in the Murray‐Darling Basin through time. Copyright © 2019 John Wiley & Sons, Ltd.  相似文献   
2.
Summary In Canada, the average annual area of burned forest has increased from around 1 million ha in the 1970’s to over 2.5 million ha in the 1990’s. A previous study has identified the link between anomalous mid-tropospheric circulation at 500 hPa over northern North America and wildland fire severity activity in various large regions of Canada over the entire May to August fire season. In this study, a northern North American study region of the hemispheric gridded 5° latitude by 10° longitude 500 hPa dataset is identified and analysed from 1959 to 1996 for a sequence of six monthly periods through the fire season, beginning in April and ending in September. Synoptic types, or modes of upper air behavior, are determined objectively by the eigenvector method employing K-means cluster analysis. Monthly burned areas from the Canadian Large Fire Database (LFDB) for the same period, 1959 to 1996, are analysed in conjunction with the classified monthly 500 hPa synoptic types. Relationships between common monthly patterns of anomalous upper flow and spatial patterns of large fire occurrence are examined at the ecozone level. Average occurrence of a monthly synoptic type associated with very large area burned is approximately 18% of the years from 1959 to 1996. The largest areas burned during the main fire (May to August) season occur in the western Boreal and Taiga ecozones – the Taiga Plains, Taiga Shield, Boreal West Shield and Boreal Plains. Monthly burned areas are also analysed temporally in conjunction with a calculated monthly zonal index (Zim) for two separate areas defined to cover western and eastern Canada. In both western and eastern Canada, high area burned is associated with synoptic types with mid-tropospheric ridging in the proximity of the affected region and low Zim with weak westerlies and strong meridional flow over western Canada. Received April 3, 2001 Revised July 13, 2001  相似文献   
3.
Blooms of the brown tide organismAureccoccus anophagefferens have recurred in the coastal bays in New Jersey since 1995 and in the coastal bays of Long Island since 1985. Intracellular viral-like particles (VLPs) were documented during 1999–2000 brown tide blooms in Little Egg Harbor, New Jersey, but it was not determined whether cells were infected during the termination of the bloom. The objective of this study was to determine if VLPs infected and lysed natural populations ofA. anophagefferens in coastal bays of New Jersey and New York in 2002 with the same frequency as in 1999–2000 and especially at the termination of the bloom. Our results confirmed that the highest percentage (37.5%) of VLP-infected cells occurred at the termination of the brown tide bloom in New Jersey in 2002. Intracellular VLPs were present throughout the bloom event. The percentage of visibly infected cells was higher at the beginning of the bloom than during the peak of the bloom. The intracellular VLPs in natural populations ofA. anophagefferens were consistent in size and shape (approximately 140 nm in diameter) and comparable to those in previous studies. Concentrated viral isolates, prepared from waters during brown tide blooms in New York and New Jersey in 2002, infected healthy laboratoryA. anophagefferens cultures in vitro. The viral isolates associated with the highest laboratory viral activity (lysis positive) were concentrated from water samples having the highest viral and bacteria concentrations. The intracellular viruses in these virally infected laboratory cultures ofA. anophagefferens were similar in size and shape to those found in natural populations. The successful isolation of a virus specific toA. anophagefferens from a brown tide bloom in the field, the similarity of ultrastructure of VLPs infecting both natural populations and laboratory infected cultures, and the pattern of VLP infection during bloom activity in combination with the observed high percentage of VLP-infected cells during bloom termination, supports, the hypothesis that viruses may be a major source of mortality for brown tide blooms in regional coastal bays of New Jersey and New York.  相似文献   
4.
Ohne Zusammenfassung  相似文献   
5.
Mitteilungen     
Ohne Zusammenfassung  相似文献   
6.
Gedenktage     
Stocks  Th. 《Ocean Dynamics》1955,8(4):165-165
Ohne Zusammenfassung  相似文献   
7.
Zusammenfassung In Gezeitengebieten wie dem vorliegenden (südliche Nordsee, wofür eine Neubearbeitung vorgelegt wird) wurde bisher meistens das den Seekarten und anderen Quellen entstammende Zahlenmaterial ohne weitere Beschickung als Grundlage für die Bearbeitung von Tiefenkarten verwendet.Dabei wurde und wird das Seekartennull meistens stillschweigend als Kartennull für Isobathenkarten mit übernommen, obwohl sich manche Bearbeiter der Fehlerhaftigkeit dieser Annahme wohl bewußt gewesen sein mögen. Besonders unangenehm macht sich diese Tatsache bemerkbar, wenn Isobathen des Seegebietes mit Isohypsen im Watt oder auf dem festen Lande und auf Inseln in Verbindung gebracht werden sollen.Die jetzt vorgelegte Tiefenkarte versucht, dieses Dilemma durch Berücksichtigung einer für das ganze Gebiet gültigen, also von dem örtlich verschiedenen Seekartennull unabhängigen Niveaufläche zu umgehen; es wird eine Methode angegeben, die im Gebiet der südlichen Nordsee angewandt wurde, und im Hinblick auf die Isobathenäquidistanz (10 m im Ergebnis, 5 m im Entwurf) kritisch auf die möglichen Fehler untersucht. Es wird ferner, erläutert an einem konkreten Beispiel, auf den Unterschied zwischen den Seekarten-Tiefenlinien (nautischen Warnlinien) und echten morphologischen Isobathen hingewiesen; allerdings ist ein Anschluß der so gewonnenen Niveaufläche für die Tiefen der südlichen Nordsee an die beiderseitigen Landeshorizonte noch nicht möglich.
A new bathymetric chart of the Southern North Sea
Summary For charts of tidal regions like that of the Southern North Sea, for which a revised edition is herewith presented, the numerical values required as basic elements for the construction of bathymetric charts have until now mostly been taken — without foregoing correction — from existing charts and other sources. Besides, in most cases, chart datum has been and still is continued to be used as ordnance datum for the construction of contour lines, though many a chart author may have been well aware of the uncorrectness of this procedure. The deficiency makes itself felt in a most disagreeable way when isobaths of the sea regions are to be combined with isohypses of regions of tidal flats or connected to such of the continent or of islands.The bathymetric chart herewith presented tries to avoid this uncorrectness by using a reference plane valid for all types of regions and, hence, independent of chart datum which is subject to local differences in height. The method that has been used for constructing the chart of the Southern North Sea is discussed and carefully scrutinized for any errors that may possibly occur with regard to the equidistance of isobaths (in this case 10 m on fair charts, 5 m on plotting charts). In addition, by way of practical example, attention is called to the difference existing between depth contours on charts (nautical danger lines) and true morphologic isobaths. It is, however, not yet possible to connect the new reference plane on which the depth contours on the new bathymetric chart of the Southern North Sea have been based to the ordnance datum used in mapping the countries adjoining the area covered by the new chart.

Une nouvelle carte bathymétrique de la partie sud de la mer du Nord
Résumé Pour l'établissement des cartes bathymétriques représentant des zones soumises à la marée comme celle de la partie sud de la mer du Nord, on s'est jusqu'ici servi des valeurs numériqúes provenant des cartes marines et d'autres sources, sans avoir corrigé ces valeurs avant leur usage. En outre, on a employé le plus souvent, et on continue encore à employer le «zéro hydrographique» comme «zéro du nivellement général» pour la construction de lignes de niveau bienque beaucoup d'auteurs de cartes se soient, sans doute, rendu compte de l'inexactitude de cette méthode. Cette défectuosit é présente des inconvénients extraordinaires lorsque des isobathes de la région marine sont à com biner avec des isohypses de zones couvrantes et découvrantes ou à relier à celles du continent.Par rapport à l'édition refondue de la carte bathymétrique présentée avec ce travail et représentant la zone soumise à la marée de la région sud de la mer du Nord, on a essayé d'éviter cette inexactitude par l'introduction d'un nouveau plan de référence qui est valable pour des régions de caractères bien différents, et qui ne dépend pas du zéro hydrographique soumis à des différences locales en hauteur. La méthode qui fut appliquée à l'établissement de cette carte est discutée dans ce travail et examinée avec soin pour éviter que des erreurs pourraient s'introduire dans des équidistances des isobathes (dans ce cas, 10 m sur les minutes de rédaction, 5 m sur les minutes de construction). En outre, un exemple pratique sert à attirer l'attention sur la différence entre des lignes de niveau (limites de danger) indiquées sur des cartes marines et des isobathes vraiment morphologiques. Cependant, il n'est pas encore possible de relier le nouveau plan de référence sur lequel s'appuient les lignes de niveau de la nouvelle carte bathymétrique, au zéro du nivellement général en usage pour la représentation topographique des pays contigues à la région couverte par cette carte.


Die Karte kann auch einzeln zum Preis von DM 3,- je Stück durch den Buchhandel oder unmittelbar vom D.H.I. bezogen werden (Druckschrift Nr. 2560 des D.H.I.).  相似文献   
8.
The potential impact of climate warming on patterns of malaria transmission has been the subject of keen scientific and policy debate. Standard climate models (GCMs) characterize climate change at relatively coarse spatial and temporal scales. However, malaria parasites and the mosquito vectors respond to diurnal variations in conditions at very local scales. Here we bridge this gap by downscaling a series of GCMs to provide high-resolution temperature data for four different sites and show that although outputs from both the GCM and the downscaled models predict diverse but qualitatively similar effects of warming on the potential for adult mosquitoes to transmit malaria, the predicted magnitude of change differs markedly between the different model approaches. Raw GCM model outputs underestimate the effects of climate warming at both hot (3-fold) and cold (8–12 fold) extremes, and overestimate (3-fold) the change under intermediate conditions. Thus, downscaling could add important insights to the standard application of coarse-scale GCMs for biophysical processes driven strongly by local microclimatic conditions.  相似文献   
9.

Acknowledgement for Referees

Reviewers of the Journal of Geodesy for Volume 79  相似文献   
10.
Geospatial data and tools are key in locating lost or missing persons in as short a time as possible. In this study, we used a geographic information system (GIS) to analyze four years of search and rescue (SAR) mission data from Colorado to determine the appropriate use of GIS for volunteer-based SAR organizations with limited resources and GIS expertise. GIS can provide more sophisticated analyses of geospatial data than simple mapping technologies, but our findings indicated that complex spatial analysis might not be required on all missions, because the majority of missions were completed within six to ten hours. Instead, new technologies such as tablets with mapping software and online GIS systems that provide quick and easy access to up-to-date geospatial data such as imagery offer capabilities that could improve mission planning. Here we provide a framework in which SAR missions can apply geospatial technologies to aid with missions, identify critical “hotspots,” and enhance postanalysis and training. The work here is highly applicable for nonprofit SAR groups when deciding on what GIS technologies to consider for their areas.  相似文献   
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