Black and Grey

Black-Box Testing of Grey-Box Behavior

A key aspect of the Object-Oriented (OO) approach is that a designer can enrich an OO system by providing suitable (re-)definitions for some of the methods of the given system. Application frameworks provide good examples of such enrichment. An OO framework typically provides a number of template methods that implement specific patterns of calls to hook methods. An application developer can cus...

Grey Cases in Cardiology and Maneuvering in a Grey Zone, Where a Grey Attitude May Yield a Black Outcome

Grey zone in medicine and namely, in cardiology, represents a perplex area that clinicians have to navigate through and deal with. Grey cases in medicine represent intricate situations and the great challenge is to maneuver appropriately in order to narrow the grey zone and/or to move grey cases out of it. This may be achieved every so often by a comprehensive clinical approach, along with an e...

Mass critical care ethics: black and white, or grey?

Black & White, Never Grey: On Interfaces, Synchronization, Pragmatics, and Responsibilities

When composing systems from components we have to deal with involved aspects like synchronization or non-functional properties like performance. It is nearly impossible to clearly specify such aspects in interfaces. Looking behind the interfaces (into grey boxes) does not solve the problem because of lost substitutability. In this paper we explain on the example of synchronization, first, how p...

Identification of pre-sliding and sliding friction dynamics: Grey box and black-box models

The non-linear dependence of pre-sliding and sliding friction forces on displacement and velocity is modelled using different physics-based and black-box approaches including various Maxwell-Slip models, neural networks, nonparametric (local) models and recurrent networks. The efficiency and accuracy of these identification methods is compared for an experimental time series where the observed ...