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101.
Landslide risk assessment and management by decision analytical procedure for Dereköy, Konya, Turkey
The Dereköy landslide threatening the town of Dereköy, Konya, Turkey is investigated in order to assess and manage the associated risk. Dereköy town, located 12 km west of Konya city center, which is the second largest city in central Anatolia, has been extending due to the demand for new settlement places in Konya for the last decade. As most of the town is situated on the slopes of Meram river valley, on which the slope movements are observed, the risk of landslide has been increasing due to these new settlements. In this study, the landslide risk in Dereköy is assessed by following the so-called decision analytical procedure. The risk is defined by multiplication of hazard and consequences of the hazard. The hazard, which is the probability of slope failure, is computed by using the first-order second-moment (FOSM) method. The possible consequences of a landslide in Dereköy are analyzed and their costs are assessed relative to each other. A decision tree for choosing among the possible alternatives for reducing the risk is constructed in order to manage the risk. 相似文献
102.
地下开采所引起的地表沉陷灾害是我国高速公路建设中所面临的一个新的课题。文章论述了条带煤采空区所引起的地表沉陷对高速公路建设的影响,建立了相关灾害的研究程式和研究方法,并利用研究成果进行了实例应用,取得了良好的效果。 相似文献
103.
A GIS-based decision support system, which incorporates local topographic and rainfall effects on debris flow vulnerability
is developed. Rainfall at a scale compatible with the digital elevation model resolution is obtained using a neural network
with a wind-induced topographic effect and rainfall derived from satellite rain estimates and an adaptive inverse distance
weight method (WTNN). The technique is tested using data collected during the passage of typhoon Tori-Ji on July 2001 over
central Taiwan. Numerous debris flows triggered by the typhoon were used as control for the study. Our results show that the
WTNN technique outperforms other interpolation techniques including adaptive inversed distance weight (AIDW), simple kriging
(SK), co-kriging, and multiple linear regression using gauge, and topographic parameters. Multiple remotely-sensed, fuzzy-based
debris-flow susceptibility parameters are used to describe the characteristics of watersheds. Non-linear, multi-variant regressions
using the WTNN derived rainfall and topography factors are derived using self-organizing maps (SOM) for the debris flow vulnerability
assessment. An index of vulnerability representing the degrees of hazard is implemented in a GIS-based decision support system
by which a decision maker can assess debris flow vulnerability. 相似文献
104.
The systematic decline of in situ networks for hydrologic measurements has been recognized as a crucial limitation to advancing
hydrologic monitoring in medium to large basins, especially those that are already sparsely instrumented. As a collective
response, sections of the hydrologic community have recently forged partnerships for the development of space-borne missions
for cost-effective, yet global, hydrologic measurements by building upon the technological advancements since the last two
decades. In this article, we review the state-of-the-art on flood monitoring in medium and large ungauged basins where satellite
remote sensing can facilitate development of a cost-effective mechanism. We present our review in the context of the current
hydro-political situation of flood monitoring in flood-prone developing nations situated in international river basins (IRBs).
Given the large number of such basins and the difficulty in acquisition of multi-faceted geophysical data, we argue that the
conventional data-intensive implementation of physically based hydrologic models that are complex and distributed is time-consuming
for global assessment of the utility of proposed global satellite hydrologic missions. A more parsimonious approach is justified
at the tolerable expense of accuracy before such missions begin operation. Such a parsimonious approach can subsequently motivate
the identified international basins to invest greater effort in conventional and detailed hydrologic studies to design a prototype
flood forecasting system in an effort to overcome the hydro-political hurdles to flood monitoring. Through a modeling exercise involving an open-book watershed concept, we demonstrate the value of a parsimonious approach
in understanding the utility of NASA-derived satellite rainfall products. It is critical now that real-world operational flood
forecasting agencies in the under-developed world come forward to collaborate with the research community in order to leverage
satellite rainfall data for greater societal benefit for inhabitants in IRBs. 相似文献
105.
基于DTM的水边线遥感信息提取方法 总被引:2,自引:0,他引:2
水边线附近的高浊度悬沙及浅滩表层的残余水体是影响水边线信息提取的重要因素。在分析长江口区不同浓度水体与背景地物光谱特征的基础上,采用决策树分析方法进行水边线提取,在分类器的节点用水深信息作为约束条件,消除了水边线附近热流对热红外波段水边线提取的影响。同时,利用参考DTM及潮位信息实施了水边线的提取,此方法有效消除了表层残余水体对水边线提取的影响。最后运用统计学中自身一致性校验及平均偏移指数来评价提取结果。结果表明,两种方法的总体提取效果较好,精度令人满意。 相似文献
106.
The high cost of land for housing within urban centres and the common desire to live within extensive residential areas in the green countryside have, in some cases, led to increasing residential development in the urban hinterland, often resulting in dispersed and sprawling development. In order to counteract such development this article seeks to provide a methodology for implementing strategies which aim is to achieve sustainable development in spatial planning. The proposed methodology, which is known as “backcasting”, aims to improve our ability to avoid undesirable future developments and to encourage those developments that are desirable. Backcasting has previously mostly been used within theoretical processes or frameworks. The backcasting exercise presented in this paper used a Python-based model to create often visionary future scenarios based on interviews with relevant experts, and then used these scenarios as input for a backwards running model. This model simulates a development that runs backwards in time, converging towards the present situation. The backcasting model presented herein has been applied to a case study in Salzburg, Austria. 相似文献
107.
《Marine Policy》2015
This article presents a decision-making model based on situations that are typically encountered in fisheries management when setting the total allowable quota. The model allows assessing the differences in outcomes when different management institutions make the decision under uncertain conditions. Social preferences are considered to measure the social expected costs raised by different institutions. Moreover, stakeholder participation and the notion of “legitimacy cost” are taken into account, the latter being defined as the cost of actions that stakeholders may take when they do not agree with decisions made by the management authority. Within this context, economic policy choices are discussed in terms of what type of institutions will generate a higher expected welfare depending on social preferences and legitimacy costs in specific contexts. Finally, this article also discusses what aspects should be considered when designing stakeholder and scientific boards in the TAC setting process. 相似文献
108.
109.
With rapid economic development in China, crops have undergone remarkable changes in both their type and spatial pattern. Timely and accurate information of crop type distribution will help government and agricultural producers quickly understand regional agricultural production conditions to better facilitate appropriate adjustments in planting patterns and policies. Another benefit of acquiring such knowledge of crops is that it should enhance regional agricultural competitiveness, optimize resource allocations, and further guarantee national food security. Towards this end, and using the Zhangye City in the Heihe River Basin as a study area, the present research elaborated upon a methodology to classify crop type distribution based on multi-temporal Thematic Mapper and Enhanced Thematic Mapper Plus (TM/ETM+) images. Using this methodology we achieved the spatial distributions of crop types in Zhangye City in 2007 and 2012, and analyzed changes in their distributions over this period. In addition, some landscape indices were calculated to clarify the landscape pattern of crops. The crop conversion potentials in 2017 were modeled using four conversion sub-models of the Multi-Layer Perceptron (MLP) neural network. Generally, the overall accuracy of crop classification in Zhangye was high, at 89.38%. From 2007 to 2012, the cultivated land area in Zhangye increased from 463.81 × 103 ha to 493.89 × 103 ha. The sowing area of corn and oilseed rape increased by 39.21 × 103 ha and 5.99 × 103 ha, respectively, while for wheat and barley the sowing area decreased by 3.61 × 103 ha and 9.14 × 103 ha, respectively. Considering other crop types as a group, their sowing area decreased by only 2.37 × 103 ha. The increase in corn sowing area mainly came from the conversion of other crops to corn, which accounted for 43.09% of its total sowing area in 2012. Furthermore, corn and oilseed rape showed a tendency of intensive sowing, whereas for wheat and barley the tendency was towards scattered sowing. For the future, corn has high conversion potential in Linze and Gaotai counties of Zhangye, while wheat, barley and oilseed rape have high conversion potentials in Minle and Shandan counties. 相似文献
110.
N. Van Cauwenbergh D. Pinte A. Tilmant I. Frances A. Pulido-Bosch M. Vanclooster 《Environmental Geology》2008,54(3):479-489
Water management in the Andarax river basin (Almeria, Spain) is a multi-objective, multi-participant, long-term decision-making
problem that faces several challenges. Adequate water allocation needs informed decisions to meet increasing socio-economic
demands while respecting the environmental integrity of this basin. Key players in the Andarax water sector include the municipality
of Almeria, the irrigators involved in the intensive greenhouse agricultural sector, and booming second residences. A decision
support system (DSS) is developed to rank different sustainable planning and management alternatives according to their socio-economic
and environmental performance. The DSS is intimately linked to sustainability indicators and is designed through a public
participation process. Indicators are linked to criteria reflecting stakeholders concerns in the 2005 field survey, such as
fulfilling water demand, water price, technical and economical efficiency, social and environmental impacts. Indicators can
be partly quantified after simulating the operation of the groundwater reservoir over a 20-year planning period and partly
through a parallel expert evaluation process. To predict the impact of future water demand in the catchment, several development
scenarios are designed to be evaluated in the DSS. The successive multi-criteria analysis of the performance indicators permits
the ranking of the different management alternatives according to the multiple objectives formulated by the different sectors/participants.
This allows more informed and transparent decision-making processes for the Andarax river basin, recognizing both the socio-economic
and environmental dimensions of water resources management. 相似文献