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171.
《Marine Policy》2017
Fishers in the UK face a range of administrative, economic and sociocultural challenges that influence the profitability and ultimate viability of their profession. While some fishers have responded to these challenges by diversifying into complementary activities such as tourism, marketing and retail, little is known of the constraints that deter individuals from adopting this strategy. This paper seeks to address this gap in knowledge by examining the relative importance of different constraints upon fisheries diversification using the Analytic Hierarchy Process (AHP). A survey of fishers and non-fishing stakeholders in the English Channel fishery revealed that respondents attributed similar levels of importance to the influence of administrative constraints, lack of opportunities, social constraints and economic factors; but considered lack of information to be relatively unimportant. The high level of inconsistency observed throughout the sample highlights a potential limitation of using AHP with research subjects who are unfamiliar with this technique. 相似文献
172.
In this study, we first define ecological technologies and the need for identification technology, and we then examine all the present methods of identification technology: Delphi method, Technology Road Mapping Method, Analytic Hierarchy Process, Patentometric method and the text mining method. Among these methods, the combination of Delphi + Analytic Hierarchy Process incorporates ecological technologies into social and economic systems for a systematic identification, and is able to build an index system for an identification model of ecological technologies, identifying technical features, technical level and performance, and economic, social and ecological benefits. Patentometric method presents an objective perspective for identification, based on the characteristics and the internal development logic of ecological technologies. We find that the Delphi + Analytic Hierarchy Process and Patentometric method are the best choices for identification of ecological technologies, because both combine the advantages of qualitative and quantitative identification. 相似文献
173.
数据可以独立于应用系统单独存在 ,即构成一个数据工程。在数据工程建设中引入监理机制是时代的呼唤 [1 ]。文章首先分析了我国工程中数据工程出现的问题 ,说明了实行数据监理的必要性。然后针对数据项目的特殊性 ,结合工程监理的实践 ,对数据监理的机制、内容、流程等进行了探讨 ,对数据监理的特点、难点及具体操作规范进行了详细分析。 相似文献
174.
175.
Focused on the current situation,monitoring system,technical management regulation,process,system composition,and information publication of the earthquake information release, we summarized the construction and development of China's earthquake information release system and expected its future. In general, China's earthquake information release systems is able to publish auto-results with M_S≥ 3. 0 from 1 to 3 minutes,M_S≥6. 0 in global from 2 to 30 minutes,and formal results with M_S≥3. 0 in China from 8 to 30 minutes,M_S≥6. 0 in global from 20 to 60 minutes. These earthquake information is released by various channels such as short message,website,microblog,mobile application,etc. 相似文献
176.
PAI-OFF: A new proposal for online flood forecasting in flash flood prone catchments 总被引:1,自引:0,他引:1
The Process Modelling and Artificial Intelligence for Online Flood Forecasting (PAI-OFF) methodology combines the reliability of physically based, hydrologic/hydraulic modelling with the operational advantages of artificial intelligence. These operational advantages are extremely low computation times and straightforward operation. The basic principle of the methodology is to portray process models by means of ANN. We propose to train ANN flood forecasting models with synthetic data that reflects the possible range of storm events. To this end, establishing PAI-OFF requires first setting up a physically based hydrologic model of the considered catchment and – optionally, if backwater effects have a significant impact on the flow regime – a hydrodynamic flood routing model of the river reach in question. Both models are subsequently used for simulating all meaningful and flood relevant storm scenarios which are obtained from a catchment specific meteorological data analysis. This provides a database of corresponding input/output vectors which is then completed by generally available hydrological and meteorological data for characterizing the catchment state prior to each storm event. This database subsequently serves for training both a polynomial neural network (PoNN) – portraying the rainfall–runoff process – and a multilayer neural network (MLFN), which mirrors the hydrodynamic flood wave propagation in the river. These two ANN models replace the hydrological and hydrodynamic model in the operational mode. After presenting the theory, we apply PAI-OFF – essentially consisting of the coupled “hydrologic” PoNN and “hydrodynamic” MLFN – to the Freiberger Mulde catchment in the Erzgebirge (Ore-mountains) in East Germany (3000 km2). Both the demonstrated computational efficiency and the prediction reliability underline the potential of the new PAI-OFF methodology for online flood forecasting. 相似文献
177.
基于层次分析法(AHP)对张掖市具有代表性的8个较大湿地区域进行生态功能综合研究,结果表明:甘肃省张掖市湿地生态功能的好坏依次排序为:祁连冰川湿地、高山灌丛草甸湿地、黑河干支流沿岸湿地、肃南明海湿地、临泽双泉湖草本沼泽、民乐永固沼泽湿地、甘州区城郊芦苇(Phragmites australis)湿地、高台盐田湿地。这一结论可为张掖市湿地资源恢复、保护和可持续发展提供科学依据。 相似文献
178.
艾比湖流域水资源承载力综合评价 总被引:7,自引:1,他引:6
通过对系统内在作用机制的分析,以新疆艾比湖流域为例,利用模糊层次分析原理建立了流域水资源承载力综合评价指标体系并对其进行了量化分析。借助德尔菲专家调查法,将模糊层次分析法运用到研究区水资源承载力综合评价指标权重的求解中,对评价指标、具体评价过程和应用方法进行了分析说明。并预测了研究区未来规划水平年水资源承载力的发展趋势和方向。提出了该区域社会经济发展和水资源配置的规划方向,并探讨提高该区域水资源承载力的良策。这也为其它区域的水资源可持续开发利用研究提供了一定的借鉴和参考。 相似文献
179.
酸性硫酸盐土的酸害暴发机制及其环境影响 总被引:4,自引:0,他引:4
酸性硫酸盐土广泛分布于热带亚热带滨海地区,当其中的硫铁矿物质与空气接触或直接暴露地表时会发生氧化而形成强烈酸害,从而导致土壤、水、大气和区域生态系统的退化,最终对动植物生长和人类的健康产生较大影响而成为全球性的热带亚热带滨海环境问题。酸性硫酸盐土的酸害暴发主要包括:(1)硫铁矿的形成、累积与埋藏过程;(2)硫铁矿的氧化与致酸过程;(3)土壤对酸的中和与缓冲过程;(4)土壤中酸的稀释与迁移过程。酸性硫酸盐土的酸害影响是上述四个过程相对强弱与综合作用的结果。酸性硫酸盐土酸害暴发可导致区域土壤环境、水环境和大气环境的酸化,以及大量金属与重金属元素的溶解与释放,引起生物生存环境的恶化与栖息地的丧失,动植物出现变态生长,而且疾病频繁,生产力下降,区域生态系统的结构和功能发生异常,生物多样性下降。 相似文献
180.