In this paper, we present ReGraph, a framework to map data from a relational to a graph database, managing a dynamic coexistence and evolution of both, not supported by related work. ReGraph has minimal impact in the existing infrastructure, providing a flexible and tailored graph model for each relational schema. It uses an initial ETL (Extract, Transform and Load) process to replicate the exi...

We describe data structures that allow e cient updates of materialized classes derived from relationship of classes in object bases. Materialization of derived classes reduces costs of retrievals and increases costs of updates. Costs of updates increase remarkably when several paths of objects derive the same object. If object bases satisfy the superkey condition proposed in this paper, consist...

In this work we define a rational extension SROEL(⊓,×) T of the low complexity description logic SROEL(⊓,×), which underlies the OWL EL ontology language. The logic is extended with a typicality operator T, whose semantics is based on Lehmann and Magidor’s ranked models and allows for the definition of defeasible inclusions. We consider both rational entailment and minimal entailment. We show t...

A theory of the B → Kη decay is proposed. It is based on the Cabbibo favored b → c̄cs process followed by a direct materialization of the c̄c pair into the η. This mechanism works due to a non-valence Zweig rule violating c-quark component of the η, which is unique to its very special nature. This non-perturbative “intrinsic charm” content of the η is evaluated using the Operator Product Expansio...

In two previous papers, we concluded that (1) the sense of coherence (SOC) scale developed by Aaron Antonovsky (1923-1994) is unable to prove the association between SOC and the physical health empirically and (2) the SOC scale is unlikely to be a fair materialization of Antonovsky's idea and, thus, unlikely to measure SOC correctly. In order to improve the scale, we developed some new question...

Recent work on MapReduce has considered the problems of skew, where a job’s tasks exhibit large variance in size and processing cost, and stragglers, tasks that run slowly due to conditions on particular nodes. In this paper, we discuss an extremely simple approach to mitigating skew and stragglers: break the workload into many small tasks that are dynamically scheduled at runtime. This approac...

Despite the variety of potential benefits to society, organizations, and individuals, telework growth has been moderate. We posit that the materialization of telework potential is viable when management recognizes its innovative value and accordingly changes the implementation paradigm from selection to adaptation and from ad hoc based temporary solution of an individual problem to the strategi...

Current trends in software development are increasingly reasoning about software applications in terms of multi-agent systems (MAS). However, the development of multi-agent applications is still a technically difficult task. One of the main barriers is the lack of comprehensive design practices to move systematically from problem analysis and agent models to effective implementations. This work...

The View Generator (VG) is a system that provides the necessary components for the definition, materialization, storage, maintenance and re-use of views over remote web-accessible databases. Through the system, clients identify web databases of interest, access their metadata and create personalized views that can be shared by other clients. Creating personalized views provides a more efficient...