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101.
The SLEUTH urban growth model was used to simulate future urban growth patterns and to explore potential environ-mental impacts of urban development under different conditions of development in Shenyang City, China. The SLEUTH model was calibrated with historical data (1988-2004) extracted from a time series of TM satellite images, and the future growth was pro-jected out to 2030 assuming three different policy scenarios: (1) current trends scenario (Scenario CT), (2) regional policy and ur-ban planning sce...  相似文献   
102.
The aims of this study were to apply, verify and compare a frequency ratio model for landslide hazards, considering future climate change and using a geographic information system in Inje, Korea. Data for the future climate change scenario (A1B), topography, soil, forest, land cover and geology were collected, processed and compiled in a spatial database. The probability of landslides in the study area in target years in the future was then calculated assuming that landslides are triggered by a daily rainfall threshold. Landslide hazard maps were developed for the two study areas, and the frequency ratio for one area was applied to the other area as a cross-check of methodological validity. Verification results for the target years in the future were 82.32–84.69%. The study results, showing landslide hazards in future years, can be used to help develop landslide management plans.  相似文献   
103.
增强现实是真实世界与虚拟信息融合的可视化窗口,增强现实与地图的结合日益受到学者的关注与重视。如何合理地在增强现实界面上表达地图内容,提高用户的认知效率是研究的难点之一。在分析AR与地图结合的特点的基础上,拓展了AR Maps的概念,并重点研究了AR Maps应用场景过程;提出了一种从宏观到微观的地图应用模式;最后设计了基于应用模式的AR Maps地图架构,构建了Android环境下的地图平台,验证了AR Maps应用模式的功能。  相似文献   
104.
Local governments have set highly ambitious greenhouse gas emission reduction targets on a strategic level, in some cases influenced by intermediary networks. Yet, the quantitative impacts of climate strategies or the sharing of best practices on emissions still remain largely unknown. The aim of this study was to examine the impact of an intermediary network on municipal greenhouse gas emissions. This was done through an econometric analysis of the emissions of municipalities that are members of the Finnish Hinku (Towards Carbon Neutral Municipalities) network, and through comprehensive qualitative interviews conducted in 40 of those municipalities. Our quantitative results show that Hinku network membership has successfully led to the lowering of greenhouse gas emission levels in participating municipalities. The qualitative interviews suggest that this is due to systematic local level climate work, enhanced by network membership. The network functions as an intermediary in two ways: by providing expertise and enabling peer-support. In addition, it has also succeeded in legitimising local level climate action. Ambitious local level climate action can also affect the ambition of national climate policy, which in turn may reflect on the amount resources allocated to local climate action.  相似文献   
105.
In the recent climate change negotiations it was declared that the increase in global temperature should be kept below 2°C by 2100, relative to pre-industrial levels. China's CO2 emissions from energy and cement processes already account for nearly 24% of global emissions, a trend that is expected to keep increasing. Thus the role of China in global GHG mitigation is crucial. A scenario analysis of China's CO2 emissions is presented here and the feasibility of China reaching a low-carbon scenario is discussed. The results suggest that recent and continued technological progress will make it possible for China to limit its CO2 emissions and for these emissions to peak before 2025 and therefore that the global 2°C target can be achieved.

Policy relevance

In signing the Copenhagen Accord, China agreed to the global 2°C target. Results from this article could be used to justify low-carbon development policies and negotiations. While many still doubt the feasibility of a low-carbon pathway to support the global 2°C target, the results suggest that such a pathway can be realistically achieved. This conclusion should increase confidence and guide the policy framework further to make possible China's low-carbon development. Related policies and measures, such as renewable energy development, energy efficiency, economic structure optimization, technology innovation, low-carbon investment, and carbon capture and storage (CCS) development, should be further enhanced. Furthermore, China can play a larger role in the international negotiations process. In the global context, the 2°C target could be reaffirmed and a global regime on an emissions mitigation protocol could be framed with countries’ emissions target up to 2050.  相似文献   
106.
《Climate Policy》2013,13(1):85-108
Abstract

To reduce the costs of mitigating greenhouse gas emissions in accordance with the Kyoto protocol, international trades of emissions quotas are allowed. The revenue from the sale of quotas may exceed the sanctions for non-compliance if these penalties are weak or poorly enforced. Under these circumstances emissions trading enables a country to benefit financially through non-compliance. To counter non-compliance due to trading a range of liability proposals have been suggested. Using a simple global model, we analyze the economic and environmental performance of these proposals for the first commitment period. In addition, the proposals are tested for their sensitivity to national circumstances and to market power. We find that penalties are sufficient to deter non-compliance if they are high enough and are effectively enforced. If the non-compliance penalties are weak or poorly enforced, the permanent reserve proposal is best able to ensure compliance by sellers at a cost similar to the competitive market equilibrium. While not sufficient to ensure compliance on their own, eligibility requirements and annual retirement of AAUs equal to actual emissions contribute to compliance at little or no cost. Hence, such provisions could complement other liability proposals.  相似文献   
107.
Amplification of structural response of r.c. base-isolated structures is expected under near-fault ground motions, yet there is a lack of knowledge of their behavior in the case of fire. To investigate the nonlinear seismic response following a fire, an incremental dynamic analysis is carried out on five-storey r.c. base-isolated framed buildings with fire-protected High-Damping-Laminated-Rubber Bearings (HDLRBs), designed in line with the Italian seismic code. Horizontal components of near-fault ground motions characterized by forward-directivity or fling-step pulse-type are considered. The nonlinear seismic response of base-isolated structures in a no fire situation is compared with that in the event of fire, at 45 (i.e. R45) and 60 (i.e. R60) minutes of fire resistance, assuming both damaged (i.e. DS) and repaired (i.e. RS) stiffness conditions. Five fire scenarios are considered assuming the fire compartment confined to the area of the first level (i.e. F1), the first two (i.e. F1/2) and the upper (i.e. Fi, i=3–5) levels, with the parametric temperature–time fire curve evaluated in accordance with Eurocode 1. The nonlinear seismic analysis is performed by using a step-by-step procedure based on a two-parameter implicit integration scheme and an initial-stress-like iterative procedure. At each step of the analysis, plastic conditions are checked at the critical (end) sections of the girders and columns, where thermal mapping with reduced mechanical properties is evaluated with the 500 °C isotherm method proposed by Eurocode 2. A viscoelastic model with variable stiffness properties in the horizontal and vertical directions, depending on the axial force and lateral deformation, simulates the response of an HDLRB.  相似文献   
108.
Earthquake loss estimation is now becoming an important tool in mitigation planning, where the loss modeling usually is based on a parameterized mathematical representation of the damage problem. In parallel with the development and improvement of such models, the question of sensitivity to parameters that carry uncertainties becomes increasingly important. We have to this end applied the capacity spectrum method (CSM) as described in FEMA HAZUS-MH. Multi-hazard Loss Estimation Methodology, Earthquake Model, Advanced Engineering Building Module. Federal Emergency Management Agency, United States (2003), and investigated the effects of selected parameters. The results demonstrate that loss scenarios may easily vary by as much as a factor of two because of simple parameter variations. Of particular importance for the uncertainty is the construction quality of the structure. These results represent a warning against simple acceptance of unbounded damage scenarios and strongly support the development of computational methods in which parameter uncertainties are propagated through the computations to facilitate confidence bounds for the damage scenarios.  相似文献   
109.
Abstract

A comprehensive hydro-ecological investigation was conducted to determine the ecological response of increased groundwater withdrawals from the Kirkwood-Cohansey aquifer system, an important source of water supply in southern New Jersey, USA. Collocated observations were made of aquatic-macroinvertebrate assemblages and stream hydrologic attributes to develop flow–ecology response relations. A sub-regional transient groundwater flow model (MODFLOW) was used to simulate three plausible high-stress groundwater-withdrawal scenarios which resulted in stream baseflow reductions of approximately 0.12, 0.20, and 0.26 m3 s-1. These reduction scenarios were used to construct flow-alteration ecological response models to evaluate aquatic-macroinvertebrate response to streamflow reduction. For example, flow-alteration ecological response models indicate that if groundwater withdrawals diminish mean annual streamflow from 1.1 to 0.6 m3 s-1, the abundance of intolerant taxa could be reduced by as much as 20%. These flow-alteration ecological response modelling results could be used by resource professionals to evaluate alternative water management strategies to determine maximum basin withdrawal rates that meet ongoing human water demand while protecting biological integrity.
Editor D. Koutsoyiannis; Guest editor M. Acreman

Citation Kennen, J.G., Riskin, M.L., and Charles, E.G., 2014. Effects of streamflow reductions on aquatic macroinvertebrates: linking groundwater withdrawals and assemblage response in southern New Jersey streams, USA. Hydrological Sciences Journal, 59 (3–4), 545–561.  相似文献   
110.
气候变化对藏东北牧业生产关键期的影响   总被引:1,自引:0,他引:1  
杜军  马鹏飞  杜晓辉  袁雷 《冰川冻土》2015,37(5):1361-1371
利用藏东北10个气象站1961-2013年逐日平均气温资料,采用反距离权重插值法、线性回归、Mann-Kendall检验等方法,分析了牧草生长季(PGS)、牧草青草期(GGD)、牲畜抓膘期(FD)和牲畜掉膘期(FLD)等牧业生产关键期的时空变化,预估了未来50 a和100 a牧业生产关键期的变化.结果表明:近53 a PGS因结束日推迟而延长1.70 d·(10a)-1,GGD平均每10 a延长1.53 d,牲畜抓膘开始期线性趋势不明显,结束期趋于推迟,FD平均每10 a延长1.84 d;牲畜掉膘开始日期显著推迟,结束日明显提前,FLD以-4.33 d·(10a)-1的速度显著缩短.PGS的变化趋势与经度呈正相关,与海拔高度为负相关.PGS突变发生较早,出现在1998年;2005年是GGD明显变长的突变点,而FD和FLD的突变时间均发生在2003年.在10 a年际变化尺度上,近30 a PGS、GGD和FD呈逐年代增加趋势,而FLD趋于减少.如果气候按升温率0.044℃·a-1变化,50 a后PGS、GGD和FD分别延长20.2、18.4和21.6 d,FLD缩短23.2 d;未来100 a PGS、GGD和FD可能分别延长40.3、36.9和43.2 d,FLD缩短46.5 d.这种变化趋势十分有利于藏东北牧草生产.  相似文献   
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