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81.
Sensing spatial distribution of urban land use by integrating points-of-interest and Google Word2Vec model 总被引:1,自引:0,他引:1
Yao Yao Penghua Liu Zhaotang Liang Jinbao Zhang 《International journal of geographical information science》2017,31(4):825-848
Urban land use information plays an essential role in a wide variety of urban planning and environmental monitoring processes. During the past few decades, with the rapid technological development of remote sensing (RS), geographic information systems (GIS) and geospatial big data, numerous methods have been developed to identify urban land use at a fine scale. Points-of-interest (POIs) have been widely used to extract information pertaining to urban land use types and functional zones. However, it is difficult to quantify the relationship between spatial distributions of POIs and regional land use types due to a lack of reliable models. Previous methods may ignore abundant spatial features that can be extracted from POIs. In this study, we establish an innovative framework that detects urban land use distributions at the scale of traffic analysis zones (TAZs) by integrating Baidu POIs and a Word2Vec model. This framework was implemented using a Google open-source model of a deep-learning language in 2013. First, data for the Pearl River Delta (PRD) are transformed into a TAZ-POI corpus using a greedy algorithm by considering the spatial distributions of TAZs and inner POIs. Then, high-dimensional characteristic vectors of POIs and TAZs are extracted using the Word2Vec model. Finally, to validate the reliability of the POI/TAZ vectors, we implement a K-Means-based clustering model to analyze correlations between the POI/TAZ vectors and deploy TAZ vectors to identify urban land use types using a random forest algorithm (RFA) model. Compared with some state-of-the-art probabilistic topic models (PTMs), the proposed method can efficiently obtain the highest accuracy (OA = 0.8728, kappa = 0.8399). Moreover, the results can be used to help urban planners to monitor dynamic urban land use and evaluate the impact of urban planning schemes. 相似文献
82.
衡水湖湿地科普宣教功能提升探究 总被引:1,自引:1,他引:0
衡水湖湿地具有独特的湿地生态系统和难得的发展机遇,生态旅游正处于蓬勃发展阶段,但科普宣教工作显得较为薄弱。介绍了衡水湖湿地科普宣教的优势条件,分析了目前湿地科普宣教现状及存在的问题,提出了提升衡水湖湿地科普宣教能力的建议。 相似文献
83.
目的:探讨CT结肠成像(CTC)检查对胃癌结肠早期转移的诊断价值。方法:选取2013年1月-2015年12月我院8例行术前CTC检查的胃癌患者。虽然在轴位断层图像上没有看到明显的腹膜小结节,但是在三维(3D)空间图像中可以见到结肠壁变形。而相应地,在多平面重组图像(MPR)显示由于结肠壁增厚导致的肠壁变形,同时,还观察到与胃癌原发灶相关的密集索条状结构以及增厚的结肠壁。结果:我们发现胃癌病灶周围的索条状硬结节与腹膜侵袭相关,并在术中探查发现这些结节分布在胃癌原发灶、胃结肠韧带以及横结肠系膜之间;我们还观察到结肠结节与腹膜侵袭结节一致。结论:将来CTC有可能被应用于鉴别胃癌经腹膜浸润结肠。 相似文献
84.
天气气候诊断型论文的选题方法及实例分析 总被引:1,自引:1,他引:0
为提高相关业务技术人员的科技论文选题能力及其写作质量,给出天气气候诊断型论文的定义,指出此型论文的研究对象与研究目的,论述了作为天气气候诊断型论’文研究对象的天气个例的罕见性、极端性、特殊性、危害性特征;依据天气个例数量,将天气气候诊断型论文分为单个例诊断分析型、双个例诊断分析型和多个例诊断分析型三种类型,在此基础上,细分为若干小类,并结合论文实例,分别对实现其选题的前提和着眼点进行了探讨。 相似文献
85.
86.
Recommending attractive thematic regions by semantic community detection with multi-sourced VGI data
Zhewei Liu Xiaolin Zhou Anshu Zhang 《International journal of geographical information science》2019,33(8):1520-1544
Attractive regions can be detected and recommended by investigating users’ online footprints. However, social media data suffers from short noisy text and lack of a-priori knowledge, impeding the usefulness of traditional semantic modelling methods. Another challenge is the need for an effective strategy for the selection/recommendation of candidate regions. To address these challenges, we propose a comprehensive workflow which combines semantic and location information of social media data to recommend thematic urban regions to users with specific interests. This workflow is novel in: (1) developing a data-driven geographic topic modelling method which utilizes the co-occurrence patterns of self-explanatory semantic information to detect semantic communities; (2) proposing a new recommendation strategy with the consideration of region’s spatial scale. The workflow was implemented using a real-world dataset and evaluation conducted at three different levels: semantic representativeness, topic identification and recommendation desirability. The evaluation showed that the semantic communities detected were internally consistent and externally differentiable and that the recommended regions had a high degree of desirability. The work has demonstrated the effectiveness of self-explanatory semantic information for geographic topic modelling and highlighted the importance of including region spatial scale into the model for an effective region recommending strategy. 相似文献
87.
Wang Wanying 《云南地理环境研究》1999,(Z1)
1 IntroductionThetechnologydisseminationinruralsareaofYunnanisacomponentofeffortstoimproveruralagriculture.Presently,Yunnan'stechnologyextensionservicesystemhasachievedasignificantscale:2439serviceorganizationswith22321staffhavebeenestab-lishedastech… 相似文献
88.
在导航系统中,基准站配置的优劣直接关系到定位的精度及系统的可用性,对利用卫星电视系统进行导航可能采用的几种基准站配置进行了讨论,并对具体问题进行了分析计算,分析认为解决好基准站配置,合理地组合导航系统,可有效地提高定位的精度及系统的可用性。 相似文献
89.
90.
介绍了我国新闻媒体传播地震灾害信息 12 0年来的发展史 ,包括 :清朝末期 ( 1872~ 1910 )和民国时期 ( 1911~ 1948)新闻媒体在宣传地震灾害信息方面的情况 ,解放后新闻媒体在减灾方面作出的贡献 相似文献