Towards fully-fledged archiving for RDF datasets

The dynamicity of RDF data has motivated the development of solutions for archiving, i.e., the task of storing and querying previous versions of an RDF dataset. Querying the history of a dataset finds applications in data maintenance and analytics. Notwithstanding the value of RDF archiving, the state of the art in this field is under-developed: (i) most existing systems are neither scalable nor easy to use, (ii) there is no standard way to query RDF archives, and (iii) solutions do not exploit the evolution patterns of real RDF data. On these grounds, this paper surveys the existing works in RDF archiving in order to characterize the gap between the state of the art and a fully-fledged solution. It also provides RDFev, a framework to study the dynamicity of RDF data. We use RDFev to study the evolution of YAGO, DBpedia, and Wikidata, three dynamic and prominent datasets on the Semantic Web. These insights set the ground for the sketch of a fully-fledged archiving solution for RDF data.

Energetic Data Security Management Scheme using Hybrid Encryption Algorithm over Cloud Environment

Now-a-days all documents are in a digital format as well as everyone need to maintain their data in electronic mode with the help of cloud servers. A cloud server provides lots of facilities to users such as remote data maintenance, huge data handling and so on. But in the case of security many cloud servers are providing probabilistic results alone. So, that a new cloud server data maintenance scheme is required to provide a high-level data security to the cloud system in an efficient manner. This paper introduces a new crypto-approach called Novel Hybrid Encryption Mode (NHEM), in which this algorithm integrates several latest approaches of crypto logics into it and provides a top-end security level to the cloud data. This NHEM is derived from the base factors of two cryptographic algorithms called Advanced Encryption Standard with 512-bit size of key frequency with Message Digest (MD5) algorithm. By using the integration of these two powerful approaches, a novel approach called NHEM is designed and it provides a huge support to preserve security on cloud medium. The cloud data needs to be protected from unwanted threats and intruders by means of raising an interruption attacks on server. The proposed approach of Novel Hybrid Encryption Mode concentrates more on access control logics and the crypto norms with respect to privacy measures. In this paper, the proposed scheme assures the data is too robust and no one can attack the data without proper credentials as well as the outcome proofs are clearly given on the resulting unit of this paper. The Advanced Encryption Standard algorithm is a well-known and powerful crypto scheme and the MD5 algorithm is also considered to be the unique unidirectional algorithm to provide security level in energetic manner. These two algorithms are combined together with the bit frequency of 512 to achieve the highest accuracy levels in data security over cloud environment as well as the resulting portion clearly illustrates that with proper graphical outcome.

Validation of the Crystallography Open Database using the Crystallographic Information Framework

Data curation practices of the Crystallography Open Database (COD) are described with additional focus being placed on the formal validation using the Crystallographic Information Framework (CIF). The cif_validate program, capable of validating CIF files against both the DDL1 and the DDLm dictionaries, is presented and used to process the entirety of the COD. Validation results collected from over 450 000 CIF files are demonstrated to be a useful resource in the data maintenance process as well as the development of the underlying ontologies. A set of programs intended to aid in the dictionary migration from DDL1 to DDLm is also presented.