Nowadays, there are plenty of data sources generating massive amounts of information that, combined with novel data analytics frameworks, are meant to support optimisation in many application domains. Nonetheless, there are still shortcomings in terms of data discoverability, accessibility and interoperability. Open Data portals have emerged as a shift towards openness and discoverability. However, they do not impose any condition to the data itself, just stipulate how datasets have to be described. Alternatively, the NGSI-LD standard pursues harmonisation in terms of data modelling and accessibility. This paper presents a solution that bridges these two domains (i.e., Open Data portals and NGSI-LD-based data) in order to keep benefiting from the structured description of datasets offered by Open Data portals, while ensuring the interoperability provided by the NGSI-LD standard. Our solution aggregates the data into coherent datasets and generate high-quality descriptions, ensuring comprehensiveness, interoperability and accessibility. The proposed solution has been validated through a real-world implementation that exposes IoT data in NGSI-LD format through the European Data Portal (EDP). Moreover, the results from the Metadata Quality Assessment that the EDP implements, show that the datasets' descriptions generated achieve excellent ranking in terms of the Findability, Accessibility, Interoperability and Reusability (FAIR) data principles.

翻译：当前，众多数据源生成海量信息，结合新型数据分析框架，有望支持多个应用领域的优化。然而，在数据的可发现性、可访问性和互操作性方面仍存在不足。开放数据门户作为推动开放性与可发现性的变革举措应运而生，但其仅规定了数据集的描述方式，未对数据本身施加任何约束。而NGSI-LD标准则致力于实现数据建模与可访问性的标准化。本文提出一种解决方案，旨在桥接这两个领域（即开放数据门户与基于NGSI-LD的数据），从而在利用开放数据门户提供的结构化数据集描述的同时，确保符合NGSI-LD标准的互操作性。该方案将数据整合为连贯的数据集，并生成高质量描述，确保全面性、互操作性与可访问性。所提方案已通过真实场景实现验证，该实现通过欧洲数据门户（EDP）以NGSI-LD格式暴露物联网数据。此外，EDP实施的元数据质量评估结果表明，生成的数据集描述在可发现性、可访问性、互操作性和可重用性（FAIR）数据原则方面达到了优秀排名。