Construction of a fluvial facies knowledge graph and its application in sedimentary facies identification

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.     

应急多源遥感元数据库集成系统的本体研究

遥感技术可以为应急救灾提供及时、准确和直观的信息。但由于存在多源数据库的数据异构和语义冲突等问题,导致大量的数据难以被有效地利用,严重影响了遥感技术在减灾救灾中的应用效果。本文利用元数据对多源异构遥感数据进行管理,提出了一种基于本体的异构数据集成共享方法,并在此基础上开发了一套针对灾害库应急的多源遥感数据库集成系统。实验表明,该方法能较好解决异构数据语义冲突问题,在一定程度上实现了在语义层次上的信息集成与共享。     

LBS中位置及其语义的研究

阐述了两种LBS位置表示方法，引入了语义位置的概念，对现有的语义位置概念作了修正。强调了位置属性也是语义位置的重要组成部分。通过对位置概念内涵和外延的分析，讨论了位置属性所包括的内容；运用层次建模，实现了位置之间关系的描述。为了能够规范化地描述语义位置，运用本体技术，对位置所包含的语义信息进行了描述，建立了能够被计算机识别和处理的OWI。位置本体模型。通过对语义位置的本体建模，实现了位置信息的知识化描述，为实现个性化服务奠定了基础。     

基于形式化本体的基础地理信息分类

从本体概念出发,以认知分类和现有的本体分类方法为基础,将地理信息概念分为元概念和复合概念两大类,并基于一定的约束条件,根据地理信息概念的元属性,以形式化方法实现基础地理信息的分类.     

Spatial Relations between Classes as Integrity Constraints

The quality and integrity of spatial data is very important to support interoperability among different systems. To reach this aim integrity rules defined by the application play an important role (for example, constraints between object classes). In this article, we propose a methodology to define integrity constraints using user level spatial relations between classes of individuals. We will also provide mapping rules from user level relations to geometric level operators to allow the computation of relations. As a case study, we will define the constraints for the class of rivers and some of its specializations.     

Structural Alignment Methods with Applications to Geospatial Ontologies

We consider the problem of enabling interoperability and information sharing among geospatial applications that use ontologies to describe their concepts and the relationships among them. We present two fully automatic alignment methods that use the graph structures of a pair of ontologies to establish their alignment, that is, the semantic correspondences between their concepts. We have tested our methods on geospatial ontologies pertaining to wetlands and four other pairs that belong to a repository that has been used in the Ontology Alignment Evaluation Initiative (OAEI). Using these ontologies, we have compared the effectiveness (precision and recall) of our methods against the Similarity Flooding Algorithm that was proposed by others and show that for each of the tested ontologies one of our methods is at least as effective as their method. We have tuned the performance of our methods by introducing a greedy approach that reduces the number of concepts that get compared. This approach reduces runtime by approximately 30% with a minor compromise to the effectiveness of the results. To further validate our approach, we participated in the OAEI competition to align a pair of ontologies, each with a few thousand concepts.     

基于本体的海洋地球化学数据互操作系统设计与实现

国际深海资源的勘查和开发,积累了大量珍贵的大洋样品和分析测试数据。为完成多源异构海洋地质化学数据的自动集成和智能检索,设计了基于大洋样品本体模型的大洋样品地质化学数据互操作系统。系统为三层架构,分别是数据层、语义层和应用层。数据层完成了数据汇交模板定制;语义层完成了模式和语义互操作;应用层完成了基于语义的一站式数据检索。系统在ODP-ICP-AES、PetDB、GEOROC3个数据库模型上进行了实验,实验结果显示:该系统在确保数据源独立性、安全性、时效性的前提下,实现了海量大洋调查数据和模型的复用。     

全球地表覆盖信息语义目录服务共享

针对元数据缺乏语义描述和隐含关系推理能力,用户无法获得匹配度较高的地表覆盖信息并且检索到的相关资源数量较少的问题,本文在传统OGC目录服务中加入本体推理机制提出了地表覆盖语义目录服务,并以国家地理信息元数据标准为原型设计了地表覆盖元数据模型。随后以此为基础构建了地表覆盖元数据本体模型,并使用网络本体语言OWL对其进行形式化表达。最终通过构建地表覆盖语义目录服务,有效提高了地表覆盖资源的查全率和查准率,实现了地表覆盖信息的精准共享。     

基于本体的地理空间实体类型语义相似度计算模型的研究

地理空间实体类型语义相似度对于类型数据库综合具有重要理论意义。本文以本体作为揭示实体深层次语义信息的方法论,提出了符合认知特性的地理空间实体类型语义相似度计算模型,并通过计算土地利用类型语义相似度对模型进行了验证.     

Abyssal geography†

Today, we are held to live in the Anthropocene, bringing to an end modern binary imaginaries, such as the separation between Human and Nature, and with them Western assumptions of progress, linear causality and human exceptionalism. Much Western critical theory, from new or vital materialism to post- and more-than-human thinking, unsurprisingly reflects this internal crisis of faith in Eurocentric or Enlightenment reasoning. At the same time, a radically different critique of modernity has gained prominence in recent years, emerging from critical Black studies, which places the Caribbean at the centre of the development of a new and distinct mode of critical thought. In attempting to grasp the ways in which Caribbean thought and practice have been seen to enable a distinctive alternative non-Eurocentric imaginary, this paper heuristically sets out a paradigmatic framing of ‘abyssal geography’. We emphasize two key points. The first is that abyssal thought is not grounded in abstract and timeless philosophical assumptions but figuratively draws upon aspects of Caribbean practices of resistance and survival, for example, from the Middle Passage, Plantation, carnival, creolization, dance forms and speculative fiction. The second is that abyssal work engages the legacies of modernity and coloniality by explicitly seeking to question the lure of ontology: seeking to disrupt, suspend and to problematize the modern project of the human and the world.