The IEC standards 61508/61511 require that reliability targets for safety instrumented functions are defined and verified. The reliability targets are given as one out of a possible four safety integrity levels. For each safety integrity level there are many design requirements, including requirements for the probability of failure on demand. Verification of the requirements for the probability...

Static integrity constraints involve only the current database state. Temporal integrity constraints involve current, past, and future database states; they can be expressed by essentially unrestricted sentences in temporal logic. Certain syntactically restricted classes of temporal constraints have been studied in their own right for considerations of feasibility or practicality; they are usua...

This paper describes a technique for importing automatically an external relational schema into Pegasus, a heterogeneous, multidatabase system. The Pegasus data model is a functional object model which supports specialization, object-identity, and nested aggregation. The import algorithm generates the definition of a Pegasus schema which captures the semantics of a relational schema containing ...

Checking the consistency of a database state generally involves the execution of integrity tests (query that returns the value true or false) on the database, which verify whether the database is satisfying its constraints or not. Many types of integrity tests have been proposed and presented in the literature. The previous works in the area of checking integrity constraints in distributed data...

In this article we define a new type of integrity constraint in XML, called an XML inclusion constraint (XIND), and show that it extends the semantics of a relational inclusion dependency. This property is important in areas such as XML publishing and ‘data-centric’ XML, and is one that is not possessed by other proposals for XML inclusion constraints. We also investigate the implication and co...

The issue of whether, and how, to obtain informed consent for research studies that use social network data has recently come to the fore in some controversial cases. Determining how to acquire valid consent that meets the expectations of participants, while minimising the burden placed on them, remains an open problem. We apply Nissenbaum’s model of contextual integrity to the consent process,...

We thank Jay Chhablani and William Freeman for their interest and comments regarding our study. The study validated axonal integrity as a measure of visual potential. In macular edema, abnormal fluid accumulation between the two plexiform layers produces mechanical stress on the bipolar axons. Considering that bipolar axons represent the sole communication between photoreceptors and ganglion ce...