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排序方式： 共有228条查询结果，搜索用时 15 毫秒
41.
数字地名词典中的类型表达和管理 总被引：1，自引：0，他引：1
在数字地名词典中恰当地表达和管理地名的类型知识,有助于数字地名词典快速、有效地处理地名相关查询.为此,该文首先从数字地名词典的应用需求出发,分析类型在数字地名词典中的作用,进而设计一个地名类型本体模型.该模型表达了地名类型之间的继承关系以及对空间关系的约束.在本体模型基础上,提出了相应的查询处理策略并进行了系统实现. 相似文献
42.
针对整个城市规划过程的参与者对规划数据的不同种类、不同层次认知需求,本文利用本体思想对包括GIS数据、规划文档、规划图件等多源异构的规划数据进行关系重构,设计本体模型要素的数据语义关系,定义数据间的关联关系,实现基于本体方法的规划领域语义表达算法,方便了各类规划参与者对规划方案认识的交流:同时根据用户特征分类,进行本体关系的逻辑推理,过滤冗余信息,进行多源异构规划数据的可视化。 相似文献
43.
Digital terrain analysis(DTA) is one of the most important contents in the research of geographical information science(GIS). However, on the basis of the digital elevation model(DEM), many problems exist in the current research of DTA in geomorphological studies. For instance, the current DTA research appears to be focused more on morphology, phenomenon, and modern surface rather than mechanism, process, and underlying terrain. The current DTA research needs to be urgently transformed from the study of landform morphology to one focusing on landform process and mechanism. On this basis, this study summarizes the current research status of geomorphology-oriented DTA and systematically reviews and analyzes the research about the knowledge of geomorphological ontology, terrain modeling, terrain derivative calculation, and terrain analytical methods. With the help of DEM data, DTA research has the advantage of carrying out geomorphological studies from the perspective of surface morphology. However, the study of DTA has inherent defects in terms of data expression and analytic patterns. Thus, breakthroughs in basic theories and key technologies are necessary. Moreover, scholars need to realize that DTA research must be transformed from phenomenon to mechanism, from morphology to process, and from terrain to landform. At present, the research development of earth science has reached the critical stage in which the DTA research should focus more on geomorphological ontology. Consequently, this study proposes several prospects of geomorphology-oriented DTA from the aspects of value-added DEM data model, terrain derivatives and their spatial relations, and macro-terrain analysis. The study of DTA based on DEM is at a critical period along with the issue on whether the current GIS technology can truly support the development of geography. The research idea of geomorphology-oriented DTA is expected to be an important exploration and practice in the field of GIS. 相似文献
44.
点状地名信息的加权泰森多边形检索法 总被引：1，自引：0，他引：1
鉴于地名库中多数地名仅以中心点坐标形式记录其空间位置信息,缺乏其空间范围的具体描述,造成地名检索中的片面性和局限性,本文在深入分析地名及其空间属性、空间关系的基础上,考虑同类型地名的不同性质在检索中的重要作用,利用泰森多边形在地名边界近似中的优势,提出了针对点状地名信息的加权泰森多边形检索法,依据同类型地名的面积属性作为权重指标构建泰森多边形,以近似表达地名的空间范围,进而描述地名间的各类空间关系;并从拓扑关系、方位关系与距离关系3个方面给出了具体公式以计算地名间的空间相似性;最后以行政区划边界近似与检索为例验证该方法。试验结果表明,该方法可较好地近似表达地名空间范围及空间关系,增强了检索词与地理信息资源在空间位置上的相似性度量,检索结果优于传统方法。 相似文献
45.
基于GIS的榆林市乡镇地名分布特征研究 总被引：1，自引：0，他引：1
利用不同的网络公开地名数据源进行数据融合,获得榆林市乡镇级居民地地名数据,在此基础上,对地名数据进行统计分类,引入地名密度和地名点距离的指标,运用GIS的分析方法,对榆林市乡镇级地名数据进行景观分析。研究得出:榆林乡镇地名从东南向西北部递减,并且呈现出聚集的分布特征;榆林市的自然人文特征直接体现在其主要地名分类的分布上,山水类地名的分布反映了榆林西北部沙漠干旱,东南部黄土丘陵、河流较密的自然特点,姓氏、军事类地名的分布则反映了榆林市的移民文化、多民族混居的民族特色,以及古代军事价值高的特点。 相似文献
46.
从旅游及地域系统复杂性的角度探讨河流旅游的概念及其内涵。首先从厘清缘起出发,分析其中的3个传统——审美与寄情的传统、人文主义与后工业化的传统,以及朝觐的传统——及其对当今研究的意义。从本体论的角度,按照旅游主体对河流本体的利用形式及程度,构建了从完全亲近、部分亲近、部分疏离、到完全疏离4个维度的连续概念;从河流客体本身所受的人工干预程度,亦构建起从无干预、弱干预、强干预到完全干预4个维度的连续概念,在此基础上将二者叠合,诠释河流旅游内涵。在此概念体系中,提出在后现代/后工业化的语境下,建立基于主观体验和地域系统耦合的研究体系,旨在探寻基于不同体验类型的河流旅游主体参与方式、分析河流旅游地系统发展演化的“过程-结构-机制”、关注游憩娱乐功能主导下河流利用方式转变及其影响、关注游憩活动在流域综合发展中的地位,并结合系统研究与传统区域研究明确方法论与技术手段。 相似文献
47.
48.
Monitoring soil moisture with satellite sensors is an effective approach for agricultural drought assessment. Currently, large quantities of sensor-derived observation data with different observation metadata models exist, and they require efficient and accurate methods of discovery. In this study, an earth observation (EO) metadata ontology with a spatiotemporal-spectral-enhanced structure is designed to solve this problem. The ontology is based on the proposed EO metadata model, which is composed of nonfunctional and functional sub-modules and supports the Open Geospatial Consortium EO profile of observations and measurements. Using EO metadata ontology, an application for soil moisture monitoring in Hubei Province in China is tested. The results indicate that metadata retrieval with a spatiotemporal-spectral-enhanced method can efficiently achieve fine-grained discovery of qualified EO metadata and obtain soil moisture monitoring information from sensor images. In summary, the spatiotemporal-spectral semantics in the proposed ontology demonstrate the use of EO metadata in the context of a soil moisture monitoring application, improving the efficiency and accuracy of EO metadata discovery. 相似文献
49.
《地学前缘(英文版)》2023,14(2):101521
Lithofacies paleogeography is a data-intensive discipline that involves the interpretation and compilation of sedimentary facies. Traditional sedimentary facies analysis is a labor-intensive task with the added complexity of using unstructured knowledge and unstandardized terminology. Therefore, it is very difficult for beginners or non-geology scholars who lack a systematic knowledge and experience in sedimentary facies analysis. These hurdles could be partly alleviated by having a standardized, structured, and systematic knowledge base coupled with an efficient automatic machine-assisted sedimentary facies identification system. To this end, this study constructed a knowledge system for fluvial facies and carried out knowledge representation. Components include a domain knowledge graph for types of fluvial facies (meandering, braided and other fluvial depositional environments) and their characteristic features (bedforms, grain size distribution, etc.) with visualization, a method for query and retrieval on a graph database platform, a hierarchical knowledge tree-structure, a data-mining clustering algorithm for machine-analysis of publication texts, and an algorithm model for this area of sedimentary facies reasoning. The underlying sedimentary facies identification and knowledge reasoning system is based on expert experience and synthesis of publications. For testing, 17 sets literature publications data that included details of sedimentary facies data (bedforms, grain sizes, etc.) were submitted to the artificial intelligence model, then compared and validated. This testing set of automated reasoning results yielded an interpretation accuracy of about 90% relative to the published interpretations in those papers. Therefore, the model and algorithm provide an efficient and automated reasoning technology, which provides a new approach and route for the rapid and intelligent identification of other types of sedimentary facies from literature data or direct use in the field. 相似文献
50.