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排序方式: 共有253条查询结果,搜索用时 22 毫秒
101.
河北省地热资源分布特征、开发利用现状、存在问题与建议 总被引:4,自引:0,他引:4
河北省境内赋存和分布有多种成因的地下热水资源,按地质构造和地貌可初步划分冀北山地区、冀西山地区、冀西北山间盆地区、河北平原区等四大地下热水区,各地已将地热直接用于地热供暖、浴疗保健、温泉洗浴、旅游、地热种植、养殖及工业利用等,但地热利用中存在着勘查评价程度差、开发利用程度低、资源浪费严重等问题。为了保护地下热水资源,做到有序、合理开发,还应加强我省地热资源开发利用管理力度。 相似文献
102.
103.
《Geoforum》2017
Anticipating the future is a key practice for the management of potential emergencies. Anticipatory action needs the future to become ready-to-hand. Focusing on the logics and practices of anticipatory action the paper discusses the relations between time and space in the context of risk and uncertainty. Spatializations of simulation technologies, preemptive emergency management and anticipatory action aim to disclose and extrapolate the future. In general, infrastructures are technologies which aim to materialize expectations concerning the future. In the case of emergency management infrastructural measures enable and/or constrain practices by inheriting specific logics.The concept of riskscapes (Müller-Mahn and Everts, 2013) poses to be a promising framework to grasp these issues. In our perspective, extrapolated riskscapes treat the future as an already interpreted and symbolically structured world. This involves not only looking at the temporality of riskscapes, but also dealing with geographies of inscribed futurity. Two case studies focusing on emergency management practices of firefighters will be deployed for illustration: the first observes the logics of preemptive emergency management and anticipatory action inscribed into materialities of infrastructures in the context of rail-bound hazmat transports; the second shows how computer simulations for crowded geographies facilitate decision-making and action for policing and crowd management.Instead of treating future in riskscapes as neutral, we highlight the politically situated practices that co-evolve with these technologies and their spatializations. The article discusses the dimension of time within riskscapes to gain a better understanding of the temporalization of space as in simulations and the spatialization of time as in infrastructures of emergency management. 相似文献
104.
Qiu Yuhai 《Astrophysics and Space Science》1996,243(1):255-258
This article describes the IPS work in the Beijing astronomical observatory including the hardware and software of the instrument and some theoretical research.The project is supported by the China National Nature Science Fundation under the program 49391400 相似文献
105.
暴雨、大暴雨等自然因素和防洪、除涝工程等社会因数是影响暴雨洪涝灾害发生、发展的重要因素。基于1984-2019年遵义市13个国家气象观测站逐日降水量资料、遵义市第一次自然灾害风险普查暴雨洪涝灾害数据,采用常规统计、突变检验、线性倾向估计、相关分析、对比分析等方法,得出遵义市暴雨、大暴雨以及受灾面积的年际、年代际以及长期变化变化特征,同时揭示农作物受灾面积的变化成因。结果表明:近36年遵义市暴雨日数及其累计降水量呈波动式微弱增加趋势,大暴雨日数及其累计降水量呈显著减少趋势,暴雨、大暴雨均具有不同的阶段性变化特征。1984-1999年农作物受灾面积呈显著上升趋势,2000-2019年农作物受灾面积呈显著下降趋势。大暴雨日数及其累计降水量与受灾面积呈显著正相关,并且具有明显的阶段性差异。暴雨洪涝灾害发生、发展既受暴雨、大暴雨等气象自然因子影响,也受气象灾害防御工程和灾害性天气预报预警水平等社会因素影响。 相似文献
106.
The Washington State/Local Tsunami Work Group adopted the NOAA Weather Radio All-Hazards Warning System to warn citizens quickly and effectively of not only tsunami hazards but also other natural or man-made hazards. In concert with an array of deep ocean tsunami detectors, land-based seismic sensors, and warning messages issued by the tsunami warning centers, NWR provides a means to expeditiously get critical decision-making information to emergency managers, elected officials, and first responders. To implement the NWR strategy effectively, a partnership was developed to add a repeater to the NWR system to provide complete coverage to the coast of Washington and to shipping lanes off the coast. The Work Group also recognized the need to disseminate time critical hazard information on tsunamis to the public on beaches and in high traffic areas, so it developed a new notification system, with the first prototype installed on 2 July 2003 in Ocean Shores, Washington. A public education program also was developed to improve the impacted communities understanding of the tsunami hazard, the warning system, and actions they should take if a tsunami occurs. 相似文献
107.
Tomoko Yamamoto 《Marine Ecology》2004,25(1):35-49
Abstract. Natural prey composition and prey selectivity of the muricid snail Muricodrupa fusca (Küster), which forages on a wide range of prey, was investigated. Natural prey composition was evaluated through correcting the apparent diet (the result of observations of the feeding behavior) by the handling time, which was determined by laboratory analysis. The apparent diet and the natural diet should generally differ because prey items that require a longer handling time will be observed with higher frequencies. Multiple regression equations were derived to relate the handling time to prey size, predator size and water temperature. A large discrepancy in the apparent versus natural diet of M. fusca was found in prey species composition and prey size. They foraged on at least 11 species of sessile and mobile prey including six limpet species, and mainly preyed on Siphonaria spp. and Lottia spp. in the field. By comparing the percentage of the natural diet to that of prey abundance in the field, M. fusca preferred Siphonaria spp. and Lottia spp. and did not select the other prey species. The selectivity of this predator was explained by optimal foraging theory and antipredator defenses of some limpet species. The relationships among attacking methods, handling time and prey selectivity are also examined. 相似文献
108.
交通拥堵对急救医疗服务时空可达性的影响——以广州市为例 总被引:2,自引:2,他引:0
时间是急救服务的敏感因素,急救服务设施可达性的时空差异对于评估急救设施的选址及急救服务调度的效率,解决公众急救医疗需求与供给之间的矛盾,辅助政府部门的决策都至关重要。交通拥堵是常见的城市问题,尤其是在城市中心区域更为明显,由于交通拥堵带来的时间滞后对急救服务产生的影响不容忽视。本文通过浮动车GPS大数据,分析交通拥堵对广州市中心城区急救医疗设施时空可达性的影响。结果表明:①在考虑道路实际通行状况的情况下,在交通高峰期,社区的急救医疗服务平均可达时间和最长可达时间分别比采用设计时速计算增加20%和25%。②可达性存在明显的时空差异。急救医疗服务可达性以急救医院为中心,沿着路网向四周呈现衰减趋势。急救医院布局较多、路网密集区域的可达性高,反之则低。交通拥堵对路网密集、行车规则设计复杂以及存在通过性交通流的地区影响显著。③对不同阻抗系数下可达性变化的敏感性分析,发现随着阻抗系数的增大,可达性变化的趋势有所放缓,紧急医疗服务可达性的分异变小;这一变化趋势在交通平峰期表现更为明显。因此,在研究城市中心区域急救医疗服务时,考虑交通拥堵对可达性的影响,需要构建基于实时交通状况的可达性评估模型,合理选择模型参数,优化实时急救医疗服务调度,提升急救服务的效率和质量。 相似文献
109.
110.