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86
Combining Specification Techniques for Processes, Data and Time
 Nordic Journal of Computing
, 2002
"... We present a new combination CSPOZDC of three well researched formal techniques for the specification of processes, data and time: CSP [17], ObjectZ [36], and Duration Calculus [40]. The emphasis is on a smooth integration of the underlying semantic models and its use for verifying properties ..."
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Cited by 25 (4 self)
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We present a new combination CSPOZDC of three well researched formal techniques for the specification of processes, data and time: CSP [17], ObjectZ [36], and Duration Calculus [40]. The emphasis is on a smooth integration of the underlying semantic models and its use for verifying properties of CSPOZDC specifications by a combined application of the modelcheckers FDR [29] for CSP and UPPAAL [1] for Timed Automata. This approach is applied to part of a case study on radio controlled railway crossings.
Duration Calculus of Weakly Monotonic Time
"... We extend Duration Calculus to a logic which allows description of Discrete Processes where several steps of computation can occur at the same time point. The resulting logic is called Duration Calculus of Weakly Monotonic Time (W DC). It allows effects such as true synchrony and digitisation to be ..."
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Cited by 23 (11 self)
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We extend Duration Calculus to a logic which allows description of Discrete Processes where several steps of computation can occur at the same time point. The resulting logic is called Duration Calculus of Weakly Monotonic Time (W DC). It allows effects such as true synchrony and digitisation to be modelled. As an example of this, we formulate a novel semantics of Timed CSP assuming that the communication and computation take no time.
The UniForM Workbench, a Universal Development Environment for Formal Methods
 FM'99
, 1999
"... The UniForM Workbench supports combination of Formal Methods (on a solid logical foundation), provides tools for the development of hybrid, realtime or reactive systems, transformation, verification, validation and testing. Moreover, it... ..."
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Cited by 19 (3 self)
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The UniForM Workbench supports combination of Formal Methods (on a solid logical foundation), provides tools for the development of hybrid, realtime or reactive systems, transformation, verification, validation and testing. Moreover, it...
Propositional interval neighborhood temporal logics
 Journal of Universal Computer Science
, 2003
"... Abstract: Logics for time intervals provide a natural framework for dealing with time in various areas of computer science and artificial intelligence, such as planning, natural language processing, temporal databases, and formal specification. In this paper we focus our attention on propositional i ..."
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Cited by 18 (11 self)
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Abstract: Logics for time intervals provide a natural framework for dealing with time in various areas of computer science and artificial intelligence, such as planning, natural language processing, temporal databases, and formal specification. In this paper we focus our attention on propositional interval temporal logics with temporal modalities for neighboring intervals over linear orders. We study the class of propositional neighborhood logics (PNL) over two natural semantics, respectively admitting and excluding pointintervals. First, we introduce interval neighborhood frames and we provide representation theorems for them; then, we develop complete axiomatic systems and semantic tableaux for logics in PNL.
Automata over Continuous Time
 Theoretical Computer Science
, 1998
"... The principal objective of this paper is to lift basic concepts of the classical automata theory from discrete to continuous (real) time. It is argued that the set of nite memory retrospective functions is the set of functions realized by nite state devices. We show that the nite memory retros ..."
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Cited by 18 (1 self)
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The principal objective of this paper is to lift basic concepts of the classical automata theory from discrete to continuous (real) time. It is argued that the set of nite memory retrospective functions is the set of functions realized by nite state devices. We show that the nite memory retrospective functions are speedindependent, i.e., they are invariant under `stretchings' of the time axis. Therefore, such functions cannot deal with metrical aspects of the reals.
Modelchecking of specifications integrating processes, data and time
, 2005
"... Abstract. We present a new modelchecking technique for CSPOZDC, a combination of CSP, ObjectZ and Duration Calculus, that allows reasoning about systems exhibiting communication, data and realtime aspects. As intermediate layer we will use a new kind of timed automata that preserve events and ..."
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Cited by 17 (3 self)
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Abstract. We present a new modelchecking technique for CSPOZDC, a combination of CSP, ObjectZ and Duration Calculus, that allows reasoning about systems exhibiting communication, data and realtime aspects. As intermediate layer we will use a new kind of timed automata that preserve events and data variables of the specification. These automata have a simple operational semantics that is amenable to verification by a constraintbased abstractionrefinement model checker. By means of a case study, a simple elevator parameterised by the number of floors, we show that this approach admits modelchecking parameterised and infinite state realtime systems. 1
Sensors and Actuators in TCOZ
 FM’99: WORLD CONGRESS ON FORMAL METHODS, LECT. NOTES IN COMPUT. SCI
, 1999
"... Timed Communicating Object Z (TCOZ) combines ObjectZ's strengths in modeling complex data and algorithms with Timed CSP's strengths in modeling realtime concurrency. TCOZ inherits CSP's channelbased communication mechanism, in which messages represent discrete synchronisations ..."
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Cited by 16 (3 self)
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Timed Communicating Object Z (TCOZ) combines ObjectZ's strengths in modeling complex data and algorithms with Timed CSP's strengths in modeling realtime concurrency. TCOZ inherits CSP's channelbased communication mechanism, in which messages represent discrete synchronisations between processes. The purpose of most control systems is to observe and control analog components. In such cases, the interface between the control system and the controlled systems cannot be satisfactorily described using the channel mechanism. In order to address this problem, TCOZ is extended with continuousfunction interface mechanisms inspired by process control theory, the sensor and the actuator. The utility of these new mechanisms is demonstrated through their application to the design of an automobile cruise control system.
Interval Duration Logic: Expressiveness and Decidability
, 2002
"... We investigate a variant of densetime Duration Calculus which permits model checking using timed/hybrid automata. We define a variant of the Duration Calculus, called Interval Duration Logic, (IDL), whose models are timed state sequences [1]. A subset LIDL of IDL consisting only of located time con ..."
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Cited by 16 (0 self)
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We investigate a variant of densetime Duration Calculus which permits model checking using timed/hybrid automata. We define a variant of the Duration Calculus, called Interval Duration Logic, (IDL), whose models are timed state sequences [1]. A subset LIDL of IDL consisting only of located time constraints is presented. As our main result, we show that the models of an LIDL formula can be captured as timed state sequences accepted by an eventrecording integrator automaton. A tool called IDLVALID for reducing LIDL formulae to integrator automata is briefly described. Finally, it is shown that LIDL has precisely the expressive power of eventrecording integrator automata, and that a further subset LIDL corresponds exactly to eventrecording timed automata [2]. This gives us an automatatheoretic decision procedure for the satisfiability of LIDL formulae.
A Graphical Calculus
 Mathematics of Program Construction. SpringerVerlag LNCS 947
, 1995
"... . We present a graphical calculus, which allows mathematical formulae to be represented and reasoned about using a visual representation. We define how a formula may be represented by a graph, and present a number of laws for transforming graphs, and describe the effects these transformations have o ..."
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Cited by 10 (1 self)
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. We present a graphical calculus, which allows mathematical formulae to be represented and reasoned about using a visual representation. We define how a formula may be represented by a graph, and present a number of laws for transforming graphs, and describe the effects these transformations have on the corresponding formulae. We then use these transformation laws to perform proofs. We illustrate the graphical calculus by applying it to the relational and sequential calculi. The graphical calculus makes formulae easier to understand, and so often makes the next step in a proof more obvious. Furthermore, it is more expressive, and so allows a number of proofs that cannot otherwise be undertaken in a pointfree way. 1 Introduction Traditionally, mathematical formulae are written down on a single line. For example, in the relational calculus [9], given four relations P , Q, R and S, we can write P ;Q " R;S to represent the relation that relates two elements x and y iff there exist u and...
Sequential Calculus.
 Information Processing Letters
, 1994
"... This paper presents an algebraic calculus like the relational calculus for reasoning about sequential phenomena. It provides a common foundation for several proposed models of concurrent or reactive systems. It is clearly differentiated from the relational calculus by absence of a general converse o ..."
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Cited by 9 (1 self)
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This paper presents an algebraic calculus like the relational calculus for reasoning about sequential phenomena. It provides a common foundation for several proposed models of concurrent or reactive systems. It is clearly differentiated from the relational calculus by absence of a general converse operation. This permits the treatment of temporal logic within the sequential calculus. 1 Introduction and general axioms.