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11.
Edy?Tonnizam Mohamad Danial?Jahed ArmaghaniEmail author Mahdi?Hasanipanah Bhatawdekar?Ramesh?Murlidhar Mohd?Nur?Asmawisham?Alel 《Environmental Earth Sciences》2016,75(2):174
Blasting operations usually produce significant environmental problems which may cause severe damage to the nearby areas. Air-overpressure (AOp) is one of the most important environmental impacts of blasting operations which needs to be predicted and subsequently controlled to minimize the potential risk of damage. In order to solve AOp problem in Hulu Langat granite quarry site, Malaysia, three non-linear methods namely empirical, artificial neural network (ANN) and a hybrid model of genetic algorithm (GA)–ANN were developed in this study. To do this, 76 blasting operations were investigated and relevant blasting parameters were measured in the site. The most influential parameters on AOp namely maximum charge per delay and the distance from the blast-face were considered as model inputs or predictors. Using the five randomly selected datasets and considering the modeling procedure of each method, 15 models were constructed for all predictive techniques. Several performance indices including coefficient of determination (R 2), root mean square error and variance account for were utilized to check the performance capacity of the predictive methods. Considering these performance indices and using simple ranking method, the best models for AOp prediction were selected. It was found that the GA–ANN technique can provide higher performance capacity in predicting AOp compared to other predictive methods. This is due to the fact that the GA–ANN model can optimize the weights and biases of the network connection for training by ANN. In this study, GA–ANN is introduced as superior model for solving AOp problem in Hulu Langat site. 相似文献
12.
P. Salinas D. Pavlidis Z. Xie H. Osman C. C. Pain M. D. Jackson 《Computational Geosciences》2018,22(5):1389-1401
Flows of multiple fluid phases are common in many subsurface reservoirs. Numerical simulation of these flows can be challenging and computationally expensive. Dynamic adaptive mesh optimisation and related approaches, such as adaptive grid refinement can increase solution accuracy at reduced computational cost. However, in models or parts of the model domain, where the local Courant number is large, the solution may propagate beyond the region in which the mesh is refined, resulting in reduced solution accuracy, which can never be recovered. A methodology is presented here to modify the mesh within the non-linear solver. The method allows efficient application of dynamic mesh adaptivity techniques even with high Courant numbers. These high Courant numbers may not be desired but a consequence of the heterogeneity of the domain. Therefore, the method presented can be considered as a more robust and accurate version of the standard dynamic mesh adaptivity techniques. 相似文献
13.
Djaafar Rehrah Rishipal R. Bansode Osman Hassan Mohamed Ahmedna 《International Journal of Environmental Science and Technology》2018,15(5):1093-1102
Qatar economy has been growing rapidly during the last two decades during which waste generation and greenhouse gas emissions increased exponentially making them among the main environmental challenges facing the country. Production of biochar from municipal solid organic wastes (SOWs) for soil application may offer a sustainable waste management strategy while improving crop productivity and sequestering carbon. This study was conducted to (1) investigate the physicochemical parameters of biochars for SOW, (2) select the best-performing biochars for soil fertility, and (3) evaluate the potential benefits of these biochars in lowering greenhouse gases (GHGs) during soil incubation. Biochars were produced from SOW at pyrolysis temperatures of 300–750 °C and residence times of 2–6 h. Biochars were characterized before use in soil incubation to select the best-performing treatment and evaluation of potential GHG-lowering effect using CO2 emission as proxy. Here, soil–biochar mixtures (0–2%w/w) were incubated in greenhouse settings for 120 days at 10% soil moisture. Soil properties, such as pH, EC, TC, and WHC, were significantly improved after soil amendment with biochar. Two biochars produced from mixed materials at 300–500 °C for 2 h and used at 0.5–1% application rate performed the best in enhancing soil fertility parameters. A significant decrease in CO2 emission was observed in vials with soil–biochar mixtures, especially for biochars produced at 500 °C compared the corresponding raw materials which exhibited an exponential increase in the CO2 emission. Hence, application of biochar to agricultural soils could be beneficial for simultaneously improving soil fertility/crop productivity while sequestering carbon, thereby reducing anthropogenic emissions of GHGs. 相似文献
14.
Osman Günay Müslim Murat Saç Mutlu İçhedef Caner Taşköprü 《Arabian Journal of Geosciences》2018,11(9):213
In this study, soil radon levels have been measured for the first time across the Ganos fault (GF), which is known as the western part of the North Anatolian Fault Zone. LR 115 Type 2 Solid State Nuclear Track Detectors (time integrated) have been applied to determine soil gas radon levels, and the survey was performed in 16 stations along the fault line. The results showed that soil gas radon concentrations and variation of concentration levels are comparable high along the fault line. It is also observed that in the middle of the Ganos Fault, fairly elevated radon levels were detected. These can be related to the activity of the fault lines. It is confirmed that the study area has a very active tectonic structure and is great location for analyzing radon variations. 相似文献
15.
Natural Hazards - Open green spaces contribute to urban/rural life in terms of ecological, recreational, spatial, economic, etc., functions as well as prevention of natural disasters, mitigation of... 相似文献
16.
Osman Turan Zafer Ayaz Seref Aksu Jan Kanar Antoni Bednarek 《Ocean Engineering》2008,35(13):1339-1356
The study investigates the experimental and numerical analysis of the occurrence of auto-parametric rolling for large, high-speed pod-driven ships in waves. Considering unique design and performance targets, the aim here is to exploit susceptibility to auto-parametric rolling behaviour and to identify probable design and operational precautions. In order to achieve this aim, an existing non-linear time-domain software to simulate capsizing and other critical manoeuvring behaviours of slow- to medium-speed conventional and podded ships in waves is being enhanced for fast pod-driven vessels and then compared against the dedicated model test conducted in long-crested regular and random waves for a large, pod-driven containership model. This paper includes the presentation of current numerical modifications for pod-driven ships and the verification analysis. 相似文献
17.
R. O. Greiling M. M. Abdeen A. A. Dardir H. El Akhal M. F. El Ramly G. M. El Din Kamal A. F. Osman A. A. Rashwan A. H. N. Rice M. F. Sadek 《International Journal of Earth Sciences》1994,83(3):484-501
Detailed structural geological and related studies were carried out in a number of critical areas in the Proterozoic basement of eastern Egypt to resolve the structural pattern at a regional scale and to assess the general characteristics of tectonic evolution, orogeny and terrane boundaries. Following a brief account of the tectonostratigraphy and timing of the orogenic evolution, the major structural characteristics of the critical areas are presented. Collisional deformation of the terranes ended about 615-600 Ma ago. Subsequent extensional collapse probably occurred within a relatively narrow time span of about 20 Ma (575 – 595 Ma ago) over the Eastern Desert and was followed by a further period of about 50 Ma of late to post-tectonic activity. The regional structures originated mainly during post-collisional events, starting with those related to extensional collapse (molasse basin formation, normal faulting, generation of metamorphic core complexes). Subsequent NNW-SSE shortening is documented by large-scale thrusting (towards the NNW) and folding, distributed over the Eastern Desert, although with variable intensity. Thrusts are overprinted by transpression, which was localized to particular shear zones. Early transpression produced, for example, the Allaqi shear zone and final transpression is documented in the Najd and Wadi Kharit-Wadi Hodein zones. Two terrane boundaries can be defined, the Allaqi and South Hafafit Sutures, which are apparently linked by the high angle sinistral strike-slip Wadi Kharit-Wadi Hodein shear zone with a tectonic transport of about 300 km towards the W/NW. In general, the tectonic evolution shows that extensional collapse is not necessarily the final stage of orogeny, but may be followed by further compressional and transpressional tectonism. The late Pan-African high angle faults were reactivated during Red Sea tectonics both as Riedel shears and normal faults, where they were oriented favourably with respect to the actual stress regime. 相似文献
18.
Samir el-Gaby Osman el-Nady Ali Khudeir 《International Journal of Earth Sciences》1984,73(3):1019-1036
The Egyptian basement rocks are gathered into three major rock groups, viz. Meatiq Group (oldest), Abu Ziran Group and Hammamat Group (youngest); the last two groups belong to the Pan-African orogenic cycle. The Meatiq Group is an old crystalline basement cropping out in gneiss domes. The Abu Ziran Group comprises the geosynclinal association which is formed of a lower ophiolite unit overlain by metasediments, volcanoclastics and locally intermediate volcanics having clear island arc characters. The Hammamat Group comprises molasse-type clastics, and penecontemporaneous Dokhan Volcanics of andesite to rhyolite composition; syn to late-tectonic calc-alkaline granites are the plutonic equivalents of the Dokhan Volcanics.The studied area lies within the foreland fold and thrust belt of a continental margin orogen. Ophiolites, particularly serpentinites, crop out along the trace of the sole thrust between the Meatiq infrastructure and the imbricated Abu Ziran nappe.Swells, developed along two geanticlines, were centers of marked calc-alkaline magmatic activity associated, at least, with gold mineralization.
Zusammenfassung Die Gesteine des ägyptischen Kristallins sind in drei Hauptgruppen unterteilt: Meatiq Group (älteste), Abu Ziran Group und Hammamat Group (jüngste); die letzten zwei Gruppen gehören dem Pan-Afrikanischen Zyklus an. Die Meatiq-Gruppe stellt einen alten Sokkel dar, der in Gneisdomen auftritt. Die Abu-Ziran-Gruppe umfaßt die Geosynklinal-Assoziation, die aus einer unteren ophiolitischen Einheit besteht, überlagert von Sedimenten, volkanoklastischen Sedimenten und lokalen intermediären Vulkaniten mit ausgeprägten Inselbogen-Eigenschaften. Die Hammamat-Gruppe besteht aus Molassetyp klastischen Sedimenten und zeitlich assoziierte Dokhan Volcanics andesitischer bis rhyolitischer Zusammensetzung. Die synbis spät-tektonische Kalkalkaligranite sind die plutonischen Aequivalente der Dokhan Volcanics.Das untersuchte Gebiet liegt im Vorland-Falten- und Decken-Gürtel eines Kontinentalrand-Orogens. Ophiolite, insbesondere die Serpentinite, treten entlang dem Ausbiß der Überschiebungsfläche zwischen dem Meatiq-Sockelstockwerk und der Abu-Ziran-Decke auf.Schwellen in Form zweier Geantiklinalen waren Zentren aktiver kalkalkaliner magmatischer Tätigkeit, begleitet zumindest von Goldvererzungen.
Résumé Les roches du socle égyptien se répartissent en trois groupes majeurs: Meatiq Group (le plus ancien); Abu Ziran Group et Hammamat Group (le plus récent); les deux derniers groupes appartiennent au cycle orogénique Pan-Africain.Le Meatiq Group est un socle cristallin ancien affleurant en dômes gneissiques. Le Abu Ziran Group comprend une association géosynclinale formée d'une unité ophiolitique inférieure suivie par des métasédiments, des volcanoclastites et localement par des roches volcaniques intermédiaires à caractere d'arc insulaire. Le Hammamat Group comprend des roches clastiques du type molassique, et des roches volcaniques pénécontemporaines de composition andésitique à rhyolitique (Dokhan Volcanics); des granites calco-alcalins syntectoniques à tardi-tectoniques sont les équivalents plutoniques des «Dokhan Volcanics».Le terrain étudié se situe dans l'avant-pays plissé et charrié d'un orogène de marge continentale. Des ophiolites, particulièrement des serpentinites, affleurent le long de la surface de charriage entre le massif autochtone de Meatiq et la nappe complexe d'Abu Ziran.Des dômes, développés le long de deux géanticlinaux, ont été les centres d'une forte activité magmatique calco-alcaline associée, au moins, à une minéralisation aurifère.
: Meatiq Group ( ), Abu Ziran Group Hammamat Group ( ); - . , . , , , , , , . , Dokhan . Dokhan - - . . , , Meatiq Abu-Ziran.相似文献
19.
Anomaly analysis is used for various geophysics applications such as determination of geophysical structure's location and
border detections. Besides the classical geophysical techniques, artificial intelligence based image processing algorithms
have been found attractive for geophysical anomaly analysis. Recently, cellular neural networks (CNN) have been applied to
geophysical data and satisfactory results are reported. CNN provides fast and parallel computational capability for geophysical
image processing applications due to its filtering structure. The behavior of CNN is defined by two template matrices that
are adjusted by a properly supervised learning algorithm. After training stage for geophysical data, Bouguer anomaly maps
can be processed and analyzed sequentially. In this paper, CNN learning and processing capability have been improved, combining
Wavelet functions and backpropagation learning algorithms. The new architecture is denoted as Wavelet-Cellular Neural networks
(Wave-CNN) and it is employed to analyze Bouguer anomaly maps which are important to extract useful information in geophysics.
At first, Wave-CNN performance is tested on synthetic geophysical data, which are created by a computer environment. Then,
Bouguer anomaly maps of the Dumluca iron ore field have been analyzed and results are reported in comparison to real drilling
results. 相似文献
20.
Peter Doucette Peggy Agouris Anthony Stefanidis Mohamad Musavi 《ISPRS Journal of Photogrammetry and Remote Sensing》2001,55(5-6)
The extraction of road networks from digital imagery is a fundamental image analysis operation. Common problems encountered in automated road extraction include high sensitivity to typical scene clutter in high-resolution imagery, and inefficiency to meaningfully exploit multispectral imagery (MSI). With a ground sample distance (GSD) of less than 2 m per pixel, roads can be broadly described as elongated regions. We propose an approach of elongated region-based analysis for 2D road extraction from high-resolution imagery, which is suitable for MSI, and is insensitive to conventional edge definition. A self-organising road map (SORM) algorithm is presented, inspired from a specialised variation of Kohonen's self-organising map (SOM) neural network algorithm. A spectrally classified high-resolution image is assumed to be the input for our analysis. Our approach proceeds by performing spatial cluster analysis as a mid-level processing technique. This allows us to improve tolerance to road clutter in high-resolution images, and to minimise the effect on road extraction of common classification errors. This approach is designed in consideration of the emerging trend towards high-resolution multispectral sensors. Preliminary results demonstrate robust road extraction ability due to the non-local approach, when presented with noisy input. 相似文献