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81.
Energy and policy providing for sustainable rural livelihoods in remote locations – The case of Cuba
Modern, small-scale renewable energy technology has the potential to enable and sustain rural livelihoods, particularly in developing countries remote locations without access to the grid. Yet, the provision of rural energy to isolated communities might not achieve the desired long-term result unless its development is part of wider national policy geared to sustainable development and social equity. This article shows how a combination of technology and policy targeted at the improvement of livelihoods in rural areas is the best solution for maximising the capacity of renewable energy to deliver services. It pinpoints the transforming processes and the institutions participating in the delivery of energy technology. This work draws on the Cuban experience of renewable energy technology, that country’s efforts to improve quality of life for remote populations, and its pledge to promote environmental sustainability. Using a sustainable livelihoods approach, the results of a survey in a rural community are analysed in the framework of existing assets and policies. The article describes how it is not only local users who benefit from a comprehensive technical, social and environmental energy approach. The same governmental administration that promotes such services has much to gain from technology that works well, benefits the poor in remote locations and protects the environment within its larger policy promoting sustainable and egalitarian society. 相似文献
82.
Husam Baalousha 《Environmental Geology》2009,58(1):85-93
Quantification of groundwater recharge is important for water resources management. Different methods can be used to estimate
groundwater recharge. The most suitable approach depends on site characteristics. Water balance model was used in this study
to quantify groundwater recharge from rainfall in Ruataniwha Basin, Hawke’s Bay, New Zealand. Because it is a closed basin,
this method was determined to be more suitable than any other method. The basin is fed by surface water flow and rainfall,
without any lateral groundwater flow. Records of surface water inflow and outflow are available with a certain degree of reliability.
To cope with uncertainty in different components of water balance, different sampling methods were used. The Mean Value Latin
Hypercube Sampling (MVLHS) was used and compared with Latin Hypercube Sampling (LHS), and Monte Carlo Simulation (MCS). It
was found the groundwater recharge from rainfall is about 415 million m3/year. Results of this study have revealed that MVLHS converges faster and with lower variance than LHS and MCS. 相似文献
83.
84.
Jörg Plöger 《Singapore journal of tropical geography》2012,33(2):212-225
The explosive growth of so‐called marginal settlements in Latin America's cities has received considerable academic attention in past decades. The inability of the state to adequately provide affordable housing for a rapidly growing urban population has meant that these neighbourhoods relied on community mobilization to achieve common objectives of basic infrastructure and legal recognition. With increasing consolidation and less need for coordinated action, many local organizations lost their rationale. Fear of crime and violence, a major concern in Latin American metropolises, is inscribed on the urban landscape by a growing number of gated and fortified residential enclaves for the better‐off. Marginal neighbourhoods, however, experience a ‘security gap’ as they receive insufficient police protection and lack the financial resources to employ private guards. In many cases, the real or perceived insecurities of inner‐city life have prompted organized bottom‐up, mostly informal and sometimes vigilante, responses. Drawing on research on the rise of informal security‐related interventions in the neighbourhoods of Lima Metropolitana, Peru, this paper explores the rationales underlying the different approaches and adoptions, including the involvement of the main actors, community associations and other local interest groups. 相似文献
85.
Hyun-Han Kwon Young-Il Moon 《Stochastic Environmental Research and Risk Assessment (SERRA)》2006,20(4):223-237
Hydrologic risk analysis for dam safety relies on a series of probabilistic analyses of rainfall-runoff and flow routing models, and their associated inputs. This is a complex problem in that the probability distributions of multiple independent and derived random variables need to be estimated in order to evaluate the probability of dam overtopping. Typically, parametric density estimation methods have been applied in this setting, and the exhaustive Monte Carlo simulation (MCS) of models is used to derive some of the distributions. Often, the distributions used to model some of the random variables are inappropriate relative to the expected behaviour of these variables, and as a result, simulations of the system can lead to unrealistic values of extreme rainfall or water surface levels and hence of the probability of dam overtopping. In this paper, three major innovations are introduced to address this situation. The first is the use of nonparametric probability density estimation methods for selected variables, the second is the use of Latin Hypercube sampling to improve the efficiency of MCS driven by the multiple random variables, and the third is the use of Bootstrap resampling to determine initial water surface level. An application to the Soyang Dam in South Korea illustrates how the traditional parametric approach can lead to potentially unrealistic estimates of dam safety, while the proposed approach provides rather reasonable estimates and an assessment of their sensitivity to key parameters. 相似文献
86.
David L. Carr 《The Professional geographer》2005,57(2):157-168
Central America's tropical forests have been felled more rapidly than those of any other world region during the latter half of the twentieth century. During this time, nearly half of Guatemala's forests were eliminated. Most of this deforestation has been concentrated in the northern department of Petén. The remaining forests in Petén are now mainly concentrated in the Maya Biosphere Reserve (MBR), the heart of the largest lowland tropical forest in Central America. The pace, magnitude, and geography of this trend is of critical importance to forest conservation and rural development efforts. This article examines socioeconomic, political, demographic, and ecological factors behind settler land use and forest clearing among 241 farm households in the Sierra de Lacandón National Park (SLNP), a core conservation zone of the MBR. Some of the factors positively related to forest clearing were household size, Q'eqchí Maya ethnicity, land owned in the previous residence, farm size, land title, and the cropping of velvet bean as a soil amendment. Education, off‐farm employment, and farm distance to a road were negatively related to farm‐level deforestation. 相似文献
87.
《Geoforum》2004,35(5):545-548
The paper examines the limited presence of critical geography in Mexico and analyses why the lack of theoretical discussion means there is a need for theory from abroad. Different stages in the development of our critical practice, our links with planning programmes, and a lack of relations with other Latin American countries are all salient features. 相似文献
88.
Latin America has long played a key role in the global provision of natural resources. Most of the continent's economies are net exporters of low-value, primary products and importers of manufactured goods at a high price. This pattern of specialised trade has highly negative consequences for economic development, the environment, and the local population’s wellbeing. Yet to date, little empirical evidence has been collected on Latin America’s total contribution to the rest of the world's regions in historical perspective. Applying the Material Flow Accounting methodology, this paper estimates the physical and monetary trade of 16 Latin American economies between 1900 and 2016. Our results show that: (i) yearly net exports of materials went from 4 Mt to 610 Mt between 1900 and 2016, and greatly accelerated since the World War II. (ii) Latin America is a net exporter of most types of materials (fossil fuels, non-energy minerals and biomass), so it harbours socio-environmental problems associated with different types of extractivism. (iii) Different regional export patterns exist: Andeans export subsoil (mining and energy carriers) while the rest export soil (land-based products). The countries with the lowest net exports are the smallest in size and with the highest population density. (iv) Europe and the USA have historically received most of the imports, but since the end of the twentieth century, the Southeast Asia region is the biggest importer of materials from Latin America. (v) The price received for exported material is much lower than the price paid for imported material; and (vi) various historical periods can be differentiated regarding the relationship between economic growth and physical trade balance. 相似文献
89.
Janice Monk 《The Professional geographer》2017,69(4):683-693
Histories of geography, especially those dealing with the twentieth century, tend to focus on geographic thought or academia rather than on practice in other arenas such as government agencies. In the United States during that period, however, the latter included a higher proportional representation of women professionals than did research-oriented universities. This article examines the careers of selected women geographers who had long-term and senior positions in Washington, DC, in agencies such as the Library of Congress, Bureau of the Census, the Department of State, and the Office of Naval Research. Drawing on sources including directories, the archives and oral history collections of the Society of Woman Geographers, and interviews conducted in the late 1980s and early 1990s, I explore four main themes: how these women came to government work, aspects of the intersections of personal and professional lives, ways in which economic and political contexts shaped their opportunities and experiences, and the nature of their contributions. 相似文献
90.
This paper presents an artificial neural network (ANN)-based response surface method that can be used to predict the failure probability of c-? slopes with spatially variable soil. In this method, the Latin hypercube sampling technique is adopted to generate input datasets for establishing an ANN model; the random finite element method is then utilized to calculate the corresponding output datasets considering the spatial variability of soil properties; and finally, an ANN model is trained to construct the response surface of failure probability and obtain an approximate function that incorporates the relevant variables. The results of the illustrated example indicate that the proposed method provides credible and accurate estimations of failure probability. As a result, the obtained approximate function can be used as an alternative to the specific analysis process in c-? slope reliability analyses. 相似文献