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181.
Although neighborhood factors have been consistently associated with health, technological difficulties in eliciting self-defined neighborhoods from large cohorts have compromised the interpretability of this research. Here, we offer a mixed-methods approach to elicit and validate self-defined neighborhoods. Participants used a customized Google.Maps interface to “draw” their neighborhood and answered questions about perceived map accuracy, neighborhood definition, and neighborhood activities. We compared geographic concordance of drawn and narrative neighborhood definitions, quantified differential accuracy by demographic characteristics, and examined factors influencing neighborhood definitions. We found similar geographic concordance between narrative and mapped boundaries in two cities, with no differences by neighborhood size. Self-reported neighborhoods had greater concordance with larger administrative areas (e.g., police precincts) than for smaller units (e.g., census tracts). To delineate their neighborhood boundaries, participants reported using administrative definitions, walking distance, their familiarity with people and structures, where they spend time, and physical landmarks. In New York City, participants also reported considering sociodemographic characteristics and transportation. Our method demonstrates the feasibility of collecting perceived (egocentric) neighborhoods through online mapping surveys, adaptable to many study settings.  相似文献   
182.
地震是对人类生存构成最大威胁的自然灾害之一,往往导致巨大的损失。本研究选取中国2000—2013年震级为4.0级以上且有人员伤亡的地震灾害统计数据作为历史案例,以基于历史案例的灾情加权综合评估模型(Assessment Method of Natural Disaster Based on Similarly Historical Cases,SHC)为基础,考虑历史案例与当前灾害的空间相关程度,获得改进的基于历史相似案例空间推演的地震伤亡人口评估(Assessment Method of Earthquake Casualties Based on Spatial Reasoning of Similarly Historical Cases,SRSHC);并选取2010年青海玉树地震、2013年四川芦山地震及2014年云南鲁甸地震作为验证案例,进行精度验证。结果表明:① 对于3个验证案例,SRSHC模型的最佳评估精度均在95%以上,表明该方法在地震伤亡人口评估方面具有一定的可行性及适用性;② SRSHC模型相较于SHC模型,参评案例的个数少且精度更高,以2010年四川芦山地震为例,当参评案例个数为3个时,SRSHC模型评估结果达到最佳(97.92%);而SHC模型参评案例个数需6个达到评估结果最佳(35.49%),这表明历史案例与当前灾害发生地区的空间相关程度对评估结果有较大影响;③ 灾情评估的精度与参评案例的个数有关,当参评案例在2个以上时,模型评估的精度随着参评案例个数的增加呈平稳下降趋势;当参评案例的个数为3~4个时,SRSHC模型的评估精度最佳。基于历史案例的灾情评估方法成本低、效率高、时效性强,且方法简单、约束条件较少、容易实现, 在灾情评估方面具有一定的实用价值。  相似文献   
183.
吴静  高宇 《测绘科学》2017,(12):39-43
针对二维欧氏空间内的移动区域对象在时空关系变化建模中存在的问题,该文提出了一种时空关系变化序列模型,并建立了时空关系变化概念邻域图。采取基于时间片的时空数据模型,通过分析移动区域间随时间变化的拓扑、距离和方位关系,解决时空关系变化的集成建模问题。该方法能有效刻画移动区域的动态时空特征。  相似文献   
184.
谢丽敏  钱海忠  何海威  刘闯  段佩祥 《测绘学报》2017,46(11):1910-1918
针对当前中小比例尺地图中居民地选取面临的专家制图经验难以形式化表达的问题,提出一种基于案例推理的居民地选取方法。首先,把制图专家对居民地交互选取结果作为案例对象,挖掘居民地案例的属性特征指标,对属性赋值和归一化处理;然后,采用逐步消元法对居民地最佳属性组合进行选择,并构建源案例库;最后,采用案例推理方法,结合KNN算法,训练案例库确定KNN算法的最佳K值,将新案例与源案例库检索匹配,得出最佳决策结果,进而指导待决策居民地的自动选取。经试验验证,该方法能够较好地还原专家的选取意向,具有较好的抗噪声能力,在面状居民地自动选取中取得了较好的效果。  相似文献   
185.
Evaluation of the utility of a geologic map can require understanding of its knowledge evolution. In such cases, online usage further requires machine representation of both the knowledge and the evolution. To meet these needs, an informal structure is developed here that involves the interaction of the three reasoning forms of abduction, induction, and deduction. Empirical results are presented that support the structure, and a foundational ontology for science knowledge is adapted to represent the structure. These results lead to a new understanding of the role of the three reasoning forms in geologic mapping and constitute a new approach to the machine representation of geologic knowledge evolution. The approach also has potential to characterize the mapping of many types of geographic regions.  相似文献   
186.
A method to visualize multiple membership maps, called ‘Colour mixture’ (CM) is described and compared with alternative techniques: defuzzification and Pixel mixture. Six landform parameters were used to derive the landform classes using supervised fuzzy k-means classification. The continuous categorical map is derived by GIS calculations with colours, where colour values are considered to represent the taxonomic space spanned by the attribute variables. Coordinates of the nine class centres (landform facets) were first transformed from multivariate to two-dimensional attribute space using factor analysis, and then projected on the Hue Saturation Intensity (HSI) colourwheel. The taxonomic value was coded with the Hue and confusion with Saturation. To improve visual impression, saturation was replaced with whiteness. Classes that were closer in attribute space were merged into similar generic colours. The CM technique limits the derived mixed-colour map to seven generic hues independently of the total number of classes, which provides a basis for automated generalization. The confusion index derived from the mixed-colour map was used to derive primary boundaries and to locate areas of higher taxonomic confusion.  相似文献   
187.
多传感器数据融合技术与应用   总被引:4,自引:0,他引:4  
研究了多传感器数据融合理论的相关算法及其在多传感器系统中的应用,分析了数据融合技术目前在应用方面存在的问题;针对应用证据理论(D-S方法)解决多传感器条件下的数据融合过程中存在的失效问题,给出了修正合成规则;通过实例对其进行了验证。  相似文献   
188.
以建筑平面图为数据源,提出了一种自动生成室内地图空间数据的方法。首先,结合室内地图空间数据的需求分析了建筑平面图的基本特征,提出了墙段、邻接节点和相邻墙段的概念,并在此基础上建立了自动生成室内地图空间数据的基本流程。然后,根据与柱子相交墙线的相邻关系,建立了与柱子关联墙体连通性的恢复方法;结合渐进扩张与图形推理判断门窗两侧墙体符号局部特征的类型,通过修正门窗外接矩形,建立了与门窗关联墙体连通性的恢复方法和将门窗转换为室内地图点状要素的方法。最后,基于相邻墙段中心线的几何关系,建立了墙体中线的提取算法。以某展览馆的建筑平面图为例进行试验,结果表明本文的方法针对多种复杂情况均有较好的适用性,有效实现了室内地图空间数据的自动生成。  相似文献   
189.
This research provides evidence for moral-licensing effects in climate-related behavior. We recruited individuals who had not travelled by airplane for private reasons during the past two years (Study 1, n = 854) or had invested in an energetic refurbishment of their homes (Study 2, n = 596) and investigated feelings and intentions toward two different problematic behaviors, namely meat consumption (Study 1) and air travel (Study 2). In a paradigm where the order of topics in the survey was varied systematically, being reminded of past climate-friendly behavior decreased the discomfort about ongoing problematic climate-related behavior in another domain (Study 1) and reduced the motivation to change the latter behavior or to mitigate its consequences (Study 2). Strength and direction of the effect were moderated by factors such as concern about climate protection, personal relevance of the problematic behavior, as well as time since and pride about the climate-friendly behavior.  相似文献   
190.
针对时空推理及信息查询中存在的时空模糊性问题,通过模糊隶属函数对模糊本体中的关系进行描述,在模糊本体5W2H语义概念模型的基础上,研究了模糊本体下的语义处理方法和推理机制,基于本体模型和规则模型探讨了模糊本体知识推理机的设计方法,并将上述研究应用于旅游景点信息领域,从而对时空推理查询及语义信息检索过程进行模拟验证。  相似文献   
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