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Research and other projectsContents
Causal Analysis of Systems
The project includes WBA and OHA, below. In addition,
Jan Sanders is investigating the preparation of a database
of causal analyses of incidents, and methods for searching
that database according to causal features of interest,
using the SERAS suite of causal analysis tools from Causalis Limited.
- WBA: Why-Because Analysis of failures
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The investigation of failures of complex systems is a wide field
of practical interest which has traditionally lacked significant
formal methods. We have developed the formal
Why-Because Analysis (WBA) method, which enables one to
develop, then formally
to prove the correctness and relatively sufficiency of causal explanations.
This formal technique is based on formal semantics and logic,
and separates the various explanatory domains: time, causation, and
deontics (regulations, obligations and operating procedures). The
primary application domain to date has been transportation accidents.
We have concentrated mainly on aircraft accidents; colleagues using WBA
at Siemens Transportation Systems and the Technical University of
Braunschweig have concentrated on railway accidents.
OHA: Ontological Hazard Analysis
Our current work (2009) is centered on derivation of safety requirements
by means of the in-house-developed method
Ontological Hazard Analysis which uses specific technical
methods to identify and keep track of hazards during refinement
from requirements specifications down to, in some cases, executable
source code. Bernd Sieker has just finished his doctoral thesis (May 2009)
on the ontological hazard analysis of train dispatching according to
German regulations. The target code is SPARK (annotated ADA executable).
Safety and Security Issues in Human-Machine Cognitive Interaction
Peter Ladkin is a Principal Investigator in CITEC, the Bielefeld Centre of Excellence in
Cognitive Interaction Technology. His project investigates principles for ensuring the safety
and security of interactions
between humans and machines such as mobile robots, of which there are quite a few around CITEC,
and highly automated airplanes. We make available here the
Project Description which was accepted by
the CITEC Scientific Council in May 2009. Bernd Sieker is
the project lead researcher May 2009-October 2012.
Sustainable protocols are methods for completing transactions and
interactions that depend upon very weak social assumptions. For
example, authentication needs in Western countries suggest the use
of digital signatures, which are administered through a certification
authority. How does one offer authentication for digital interactions
in societies in which trust in central authority is very weak or absent?
Avinanta Tarigan from Jakarta finished his thesis, which offered an answer
to this question, in 2007.
I Made Wiryana, also from Jakarta, has led many high-profile urgent
projects technically. He is a personal IT advisor to the Indonesian
president and technical director of the presidential WWW site.
Made's doctoral thesis concerned his methods for ensuring quality of
the service provided to users by an software-based IT development in
an environment in which there are many conflicted cultural constraints.
His work involved "Participatory Action Research", that is, he reported
in his thesis on actual projects which he had led. He employed
"Lightweight Why-Because Analysis", LWBA, an adaptation of WBA to analyse
causally the provision of service in an IT project, and thereby to find out
where reasons might lie for success or failure. His dissertation was awarded
a distinction, one of seven in Informatics in our faculty in the period
August 2008 - July 2009.
Aditya Priowirjanto in analysing the implementation of WiMax as a technology
of choice for wide-coverage Internet access in Indonesia.
Foundations of Systems Theory
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This work investigates the logical and philosophical foundations
of the notions of success and failure of complex systems. The
first question is: what is a system? Most social theorists,
biologists, physicists, organisational theorists, and computer
scientists take a system to be a collection of objects with
behavior (often called actors. A central task is to derive
the emergent behavior of the collection (the system) from
knowledge of the behavior and interactions of the actors. Another
task is to explain the influence of the system on the behavior and
interactions of the actors. Systems interact with their
environment, which is the collection of objects that are not
considered part of the system. Systems also have subsystems,
which are subcollections of actors with distinctive interactions
of special interest, or whose emergent subsystem properties are
interesting in some way.
We aim to define a standard set of concepts for systems
theory which will incorporate the notions of system in such diverse
fields as Shannon's communication theory, Luhmann's sociological
systems theory, Coleman's Rational Choice social theory, biological
systems theory, systems of subatomic particles, and
computer operating systems and software systems.
We are particularly concerned with teleological systems, which
are systems with a goal, corresponding to one of the binary
classifiers in Parsons' social systems taxonomy, and the main
interest of artifactual systems engineers. Our main interest is
in the correctness and failure of such systems, as exemplified in
the WBA and CSA projects.
Previous Research Projects