Roaming service for electric vehicle charging using blockchain-based digital identity

We present a suitable approach to address the electric vehicle charging roaming problem (e-roaming). Blockchain technologies are applied to support the identity management process of users charging their vehicles and to record energy transactions securely. At the same time, off-chain cloud-based storage is used to record the transaction details. A user wallet settled on a mobile application stores user verified credentials; a backend application in the vehicle charging station validates the user credentials to authorize the energy transaction. The current model can be applied to similar contexts where the user may be required to keep several credentials from different providers to authenticate digital transactions.info:eu-repo/semantics/publishedVersio

A blockchain ontology for DApps development

Decentralized Applications, or DApps, provide distributed trusted applications that use blockchains. They are often composed of several services, such as transaction scalability protocols, decentralized storage and distributed computing solutions. In order to help formalize these applications, facilitate their development and improve their interoperability, we propose a novel blockchain Ontology focused on the concepts involving DApps. This ontology extends the existing EthOn ontology. It defines several key concepts related to DApps development, as well as the relations between these concepts. It features the formalization of known use cases and design patterns of blockchain technology through blockchain patterns. We use Semantic Web Rule language (SWRL) in order to define rules that express constraints on the formalized concepts. We then execute an inference engine and obtain new constraints on the properties of a defined DApp, such as its cost, based on the DApp characteristics and the services it uses. For illustration we show the inference of constraints between the Ethereum blockchain and its sidechain Polygon. We apply our research work in the field of blockchain video games. This application shows how to use the ontology to model DApps, and can be adapted to other fields.info:eu-repo/semantics/publishedVersio

O passado e o futuro da cadeia produtiva do arroz em Mato Grosso.

Introdução. Antecedentes. Evolução da produção e dinâmica do arroz em Mato Grosso. Considerações sobre área cultivada e produtividade do arroz em Mato Grosso, no período de 1990 a 2012. Histórico da prospecção de demandas na orizicultura matogrossense. Estratégias de transferência de tecnologia na cadeia produtiva do arroz em Mato Grosso. Impactos das atividades de transferência de tecnologia na cadeia produtiva do arroz em Mato Grosso. Situação atual da orizicultura mato-grossense. Futuro do arroz em Mato Grosso. Demandas de pesquisa e desenvolvimento e transferência de tecnologia. Anexos. Referências.bitstream/item/135253/1/CNPAF-doc308.pd