Object Orientation in Critical Systems: Yes, in Moderation

Object orientation is a powerful and widely used paradigm for abstraction and structuring in programming. Many languages are designed with this principle or support different degrees of object orientation. In synchronous languages, originally developed to design embedded reactive systems, there are only few object-oriented influences. However, especially in combination with a statechart notation, the modeling process can be improved by facilitating object orientation as we argue here. At the same time the graphical representation can be used to illustrate the object-oriented design of a system. Synchronous statechart dialects, such as the SCCharts language, provide deterministic concurrency for specifying safety-critical systems. Using SCCharts as an example, we illustrate how an object-oriented modeling approach that supports inheritance can be introduced. We further present how external, i.e., host language, objects can be included in the SCCharts language. Specifically, we discuss how the recently developed concepts of scheduling directives and scheduling policies can be used to ensure the determinism of objects while retaining encapsulation.

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Animal Recognition and Eye Movements

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000015 ◽

2010 ◽

Vol 57 (2) ◽

pp. 117-125 ◽

Cited By ~ 3

Author(s):

Toby J. Lloyd-Jones ◽

Juergen Gehrke ◽

Jason Lauder

Keyword(s):

Eye Movements ◽

Response Times ◽

Real Life ◽

Object Orientation ◽

Decision Task ◽

Line Drawings ◽

Object Decision ◽

Individual Features ◽

And Performance

We assessed the importance of outline contour and individual features in mediating the recognition of animals by examining response times and eye movements in an animal-object decision task (i.e., deciding whether or not an object was an animal that may be encountered in real life). There were shorter latencies for animals as compared with nonanimals and performance was similar for shaded line drawings and silhouettes, suggesting that important information for recognition lies in the outline contour. The most salient information in the outline contour was around the head, followed by the lower torso and leg regions. We also observed effects of object orientation and argue that the usefulness of the head and lower torso/leg regions is consistent with a role for the object axis in recognition.

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Customization of Rational Unified Process (RUP) Methodology for Safety-Critical Systems

International Review on Computers and Software (IRECOS) ◽

10.15866/irecos.v11i6.9184 ◽

2016 ◽

Vol 11 (6) ◽

pp. 566

Author(s):

Mina Zaminkar ◽

Mohammad Reza Reshadinezhad

Keyword(s):

Critical Systems ◽

Safety Critical ◽

Unified Process ◽

Safety Critical Systems

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Formal Verification of Control System Software

10.23943/princeton/9780691181301.001.0001 ◽

2019 ◽

Author(s):

Pierre-Loïc Garoche

Keyword(s):

Control System ◽

Formal Verification ◽

Formal Analysis ◽

Critical Systems ◽

System Software ◽

Unified Approach ◽

Verification Methods ◽

Autonomous Cars ◽

Computer Scientists ◽

Verification Techniques

The verification of control system software is critical to a host of technologies and industries, from aeronautics and medical technology to the cars we drive. The failure of controller software can cost people their lives. This book provides control engineers and computer scientists with an introduction to the formal techniques for analyzing and verifying this important class of software. Too often, control engineers are unaware of the issues surrounding the verification of software, while computer scientists tend to be unfamiliar with the specificities of controller software. The book provides a unified approach that is geared to graduate students in both fields, covering formal verification methods as well as the design and verification of controllers. It presents a wealth of new verification techniques for performing exhaustive analysis of controller software. These include new means to compute nonlinear invariants, the use of convex optimization tools, and methods for dealing with numerical imprecisions such as floating point computations occurring in the analyzed software. As the autonomy of critical systems continues to increase—as evidenced by autonomous cars, drones, and satellites and landers—the numerical functions in these systems are growing ever more advanced. The techniques presented here are essential to support the formal analysis of the controller software being used in these new and emerging technologies.

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