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51.

Reviews of geographic software in this article:

DEMO-GRAPHICS: WORLD POPULATIONS AND PROJECTIONS.

ESP

GAUSS.

CEMODEL S. Damus

LIMDEP. William H. Greene

MICROSTAT 4.1

OTIS

PCIPS. (Personal Computer Image Processing System). H.J. Meyers and R. Bernstein.

REGRESSION ANALYSIS OF TIME SERIES (RATS)

SPSS/PC+

URBAN DATA MANAGEMENT SOFTWARE (UDMS)  相似文献   
52.
Understanding climate change impacts on hydrological regime and assessing future water supplies are essential to effective water resources management and planning, which is particularly true for the Tibetan Plateau (TP), one of the most vulnerable areas to climate change. In this study, future climate change in the TP was projected for 2041–2060 by a high‐resolution regional climate model, RegCM4, under 3 representative concentration pathways (RCPs): 2.6, 4.5, and 8.5. Response of all key hydrological elements, that is, evapotranspiration, surface run‐off, baseflow, and snowmelt, to future climate in 2 typical catchments, the source regions of Yellow and Yangtze rivers, was further investigated by the variable infiltration capacity microscale hydrological model incorporated with a 2‐layer energy balance snow model and a frozen soil/permafrost algorithm at a 0.25°×0.25° spatial scale. The results reveal that (a) spatial patterns of precipitation and temperature from RegCM4 agree fairly well with the data from China Meteorological Forcing Dataset, indicating that RegCM4 well reproduces historical climatic information and thus is reliable to support future projection; (b) precipitation increase by 0–70% and temperature rise by 1–4 °C would occur in the TP under 3 RCPs. A clear south‐eastern–north‐western spatial increasing gradient in precipitation would be seen. Besides, under RCP8.5, the peak increase in temperature would approach to 4 °C in spring and autumn in the east of the TP; (c) evapotranspiration would increase by 10–60% in 2 source regions due to the temperature rise, surface run‐off and baseflow in higher elevation region would experience larger increase dominantly due to the precipitation increase, and streamflow would display general increases by more than 3% and 5% in the source regions of Yellow and Yangtze rivers, respectively; (d) snowmelt contributes 11.1% and 16.2% to total run‐off in the source regions of Yellow and Yangtze rivers, respectively, during the baseline period. In the source region of Yangtze River, snowmelt run‐off would become more important with increase of 17.5% and 18.3%, respectively, under RCP2.6 and RCP4.5 but decrease of 15.0% under RCP8.5.  相似文献   
53.
利用ECHAM5/MPI-OM模式SRES A1B气候情景下预估2016-2075年间60 a的气温及降水资料,通过分析其总体趋势、年代际变化及突变特征,研究德令哈盆地未来气候的变化趋势。预估结果显示:2016-2075年,德令哈盆地气温将可能呈上升趋势,四季及年平均气温的变化总体上基本保持一致,上升幅度在3~4 ℃之间,其中夏季和全年的增温速率相对较大;降水量在未来60 a将基本保持平稳,有微弱的下降趋势,年际间变化以夏季最为显著,降水不均将易导致极端气候事件的发生;无论气温还是降水,预估未来都将有突变发生,气温将在2035年前后发生一次突变,降水量则分别在2030 s末和2040 s初各发生一次突变。  相似文献   
54.
Volume 111 Index     
《The Journal of geography》2012,111(6):264-265
Abstract

Concepts related to alternative map projections can be difficult to explain to students given the diversity and complexity of available projections. Students frequently have trouble understanding how distortions caused by the choice of a projection can affect map readability and comprehension. Programs available for personal computers now provide geography and cartography instructors with a method for interactively educating students concerning the distortions associated with alternative map projections. Such software can be incorporated into laboratory assignments in introductory geography courses or in more advanced courses that deal with map design or thematic cartography.  相似文献   
55.
本文介绍了一种可以对来自于单一圆轨道的锥束投影数据进行精确重建的分析方法。特别是,通过利用光谱外推技术获得相应的重建算法。这一工作总结了Tuy充分条件和Smith充要条件,并且该分析方法对解决数据不完整的问题是有意义。  相似文献   
56.
This paper discusses methodological problems of accurate area determination in the cadaster. The paper contrasts the ambiguous legal definition of the parcel boundary and parcel area in relation to the theoretically well-defined geodetic parcel boundary and the geodetic parcel area on the reference ellipsoid. To align with the real world, parcel area must account for terrain elevation. Various approximate methods for area determination which can be used in the cadaster are tested. A highly accurate method for parcel area computation is proposed, based on an equal-area projection. Considering the geodetic parcel area as a reference, the achievable accuracy of different methods is evaluated. For this analysis, the coordinates of the parcel boundary points are treated as error-free. Finally, the relevance of various systematic errors is discussed in relation to the statistical uncertainty of the parcel area, which could be gained by an a real-time kinematic GNSS survey. A case study is presented for the territory of Slovenia, its georeferencing rules, land demarcation pattern, and characteristics of its topography. Based on the results of this study, some general recommendations for the parcel area determination are given.  相似文献   
57.
Does democratization help countries mitigate climate change? On the one hand, by increasing the value placed on quality of life, creating more opportunity for environmental actors to influence policymaking and holding elected politicians accountable, an increase in democratic institution and process should promote emissions reduction. On the other hand, the desire to safeguard individual freedom presumably brings with it an aversion to intervene in lifestyle and market decisions, thereby raising the risk of climate inaction. This outcome is further encouraged by the political need to balance (conflicting) environmental and energy interests.

This article evaluates the thesis that democratization promotes mitigation in light of national emissions levels from 1990 to 2012. Using data from the Freedom House, Polity IV and V-Dem indices, World Bank World Development Indicators and the World Resources Institute Climate Data Explorer it conducts a large-N investigation of the emissions levels of 147 countries. Although several quantitative studies have found that domestic political regimes affect emissions levels, this article goes beyond existing research by building a more sophisticated – multilevel- research design to determine whether democracy: (a) continues to be an important driver of emissions when country-level clustering is accounted for and (b) has uniform effects across countries. The results indicate that, even after controlling for country-level clustering and holding constant the other confounding factors, democracy is indeed a significant driver. More strikingly, they reveal that while democracies tend to have lower emissions than non-democracies, democratization spells within the same country do not have the same kind of inhibitory effects as they do between countries. This article also finds tentative evidence that the type of electoral system plays a critical role in shaping the effect of democratization on individual countries.

Key policy insights
  • Democracies tend to perform better in terms of emission levels than non-democracies.

  • Democratization has non-uniform effects across different countries, with the type of electoral system playing a key role in determining the effect that democratization has on national emissions.

  • Further research is needed to develop our understanding of how the political context influences emissions, especially with regard to the influence of pro and anti-decarbonisation actors.

  相似文献   
58.
Concern about rapid population growth in Australia's large cities and slower growth in many non-metropolitan areas has stimulated a range of government policies attempting to lift non-metropolitan growth rates. However, there is relatively little research on which to base these policies. It would be helpful to understand more about the consequences of current demographic trends continuing and the effects of alternative migration patterns. This paper presents sub-national population projections for Australia over the horizon 2011–2041, basing the projections on more socially meaningful Remoteness Areas instead of common statistical geographies. Three sets of projections were generated: a Current Direction scenario in which recent demographic trends are maintained, a Regional Immigration scenario in which more immigrants settle in regional and remote areas, and a Metro Exodus scenario in which there is increased internal migration from metropolitan to non-metropolitan areas. The future of Australia's population geography is shown to be one of spatially varying growth and population ageing, and continued metropolitanisation. In regional areas rapid population ageing will lower natural increase rates and thus reduce overall growth, resulting in a falling share of the national population. Policy measures attempting to increase the share of growth in regional areas will struggle against natural demographic forces operating in the opposite direction.  相似文献   
59.
CTA作为一种新的非损伤血管成像技术是诊断血管疾病的重要技术之一。只有当造影剂达到适当的浓度时,触发主扫描才能获得高质量的血管图像。目前最常用的造影剂监控方法是基于图像重建的监控方法,本文将提出一种基于扇形束投影重排的血管造影剂监控方法。这种方法直接对扇形束投影重排后获取监控截面内造影剂的变化量,从而可以监测造影剂的出现与否。相比于基于图像重建的方法,本文提出的方法不需要进行图像重建,因此具有更好的实时监控性和更低的监控成本,具有一定的现实意义。  相似文献   
60.
谢江丽  李帅  姚远 《中国地震》2019,35(2):389-398
利用统计年鉴、人口普查数据、遥感影像等资料,将乌鲁木齐市按区县级行政区域为单位提取近10年的人口数据,确定各区县历年来人口分布变化情况。挖掘研究区内人口-时间变量关系,建立人口预测模型——GM(1,1)模型,预测未来2年乌鲁木齐各区县人口数据,以弥补数据库数据因滞后2年无法及时更新所导致的数据空缺。  相似文献   
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