R. Alur and T.A. Henzinger. Real-time systems = discrete systems + clock variables. Software Tools for Technology Transfer, 1:86--109, 1997.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....Checking Problem In this section we survey the state of the art in model checking infinite state systems. Again, we concentrate exclusively on discrete infinite state systems and neglect, e.g. dense infinite state structures related to timed or hybrid systems, which are covered, for instance, in [3] and [2] Due to the broad scope of existing model checking algorithms, we have chosen to sketch only the main ideas behind the relevant results complemented by appropriate references: for decidable model checking problems we briefly present the developed algorithms together with their complexity; ....

R. Alur and T.A. Henzinger. Real-time systems = discrete systems + clock variables. Software Tools for Technology Transfer, 1:86--109, 1997.

....in the Stanford Temporal Verifier support system step[BBC 95] We refer the reader to the paper [BMSU97] which uses clocked transition systems to model and verify the generalized railroad crossing benchmark problem. A model similar to the cts model presented here was introduced in [AH94] and proof rules for establishing response properties for this model were presented in [HK94] However, the response verification rules presented there for the general case were based on consideration of the region graph associated with timed automata which, in many cases, becomes very big. Our ....

R. Alur and T.A. Henzinger. Real-time system = discrete system + clock variables. In T. Rus and C. Rattray, editors, Theories and Experiences for Real-time System Development, AMAST Series in Computing 2, pages 1--29. World Scientific, 1994.

....we may want to prove constitutes an even higher portion of the total set of properties of interest than in the case of untimed reactive systems. We refer the reader to [Hen92] and [Pnu92] for further discussions of this point. A model similar to the cts model presented here was introduced in [AH94] and proof rules for establishing response properties for this model were presented in [HK94] However, the response verification rules presented there for the general case were based on consideration of the region graph associated with timed automata which, in many cases, becomes very big. Our ....

R. Alur and T.A. Henzinger. Real-time system = discrete system + clock variables. In T. Rus and C. Rattray, editors, Theories and Experiences for Real-time System Development, AMAST Series in Computing 2, pages 1--29. World Scientific, 1994.

....in the Stanford Temporal Verifier support system step[BBC 95] We refer the reader to the paper [BMSU97] which uses clocked transition systems to model and verify the generalized railroad crossing benchmark problem. A model similar to the cts model presented here was introduced in [AH94] and proof rules for establishing response properties for this model were presented in [HK94] However, the response verification rules presented there for the general case were based on consideration of the region graph associated with timed automata which, in many cases, becomes very big. Our ....

R. Alur and T.A. Henzinger. Real-time system = discrete system + clock variables. In T. Rus and C. Rattray, editors, Theories and Experiences for Real-time System Development, AMAST Series in Computing 2, pages 1--29. World Scientific, 1994.

....for verifying real time systems under the cts model. The move from tts to cts brings us closer to the approach proposed in [AL94] which also recommends handling real time with a minimal extension of the reactive systems formalism. A model similar to the cts model presented here was introduced in [AH94], and proof rules for establishing response properties for that model were presented in [HK94] However, the response verification rules presented there for the general case were based on consideration of the region graph associated with timed automata which, in many cases, becomes very big. Our ....

R. Alur and T.A. Henzinger. Real-time system = discrete system + clock variables. In T. Rus and C. Rattray, editors, Theories and Experiences for 28 Real-time System Development, AMAST Series in Computing 2, pages 1--29. World Scientific, 1994.

....so called timed safety automata [HNSY94] Timed safety automata are timed automata [AD94] without acceptance conditions; their liveness is imposed uniformly as a progress condition on time. Timed safety automata have been used extensively for the specification and verification of real time systems [AH93b, DOY94, HNSY94, HK94]. It has been argued that with the explicit consideration of time, acceptance conditions are no longer useful abstractions to enforce liveness [Hen92] and this paper corroborates that belief. We look at both the time abstract expressive power (Section 3) and the timed expressive power (Section ....

R. Alur and T.A. Henzinger. Real-time system = discrete system + clock variables. In T. Rus, editor, Proceedings of the First AMAST Workshop on Real-time Systems, 1993. To appear.

....socalled timed safety automata [11] Timed safety automata are timed automata [2] without acceptance conditions; their liveness is imposed uniformly as a progress condition on time. Timed safety automata have been used extensively for the specification and verification of real time systems [6, 7, 11, 9]. It has been argued that with the explicit consideration of time, acceptance conditions are no longer useful abstractions to enforce liveness [8] and this paper corroborates that belief. We look at both the time abstract expressive power (Section 3) and the timed expressive power (Section 4) of ....

R. Alur and T.A. Henzinger. Real-time system = discrete system + clock variables. In Proc. of the First AMAST Workshop on Real-time Systems, 1993. To appear.

....) 1 ; x 1 ) of a rectangular automaton is divergent if the infinite sum X ft i j i 0 and ( i 1 ; x i 1 ) 2 ffi( i ; x i ) is a time step of duration t i g diverges. To restrict our attention to divergent runs, we can modify an n dimensional rectangular automaton H in a standard way [3]. We add an additional clock variable at coordinate n 1, so that the dimension becomes n 1. For each vertex 2 V , we introduce a new vertex tick and two edges e = tick ) and e 0 = tick ; Define pre(e) i = post(e) pre(e 0 ) i = post(e 0 ) R for 1 i n; pre(e) n 1 = ....

R. Alur and T.A. Henzinger. Real-time system = discrete system + clock variables. Software Tools for Technology Transfer, 1:86--109, 1997.

....5000 Gamma55 d Gamma45 far d = 5000 Fig. 12. Train automaton predicate that characterizes exactly the safe values for the parameter ff. Multiple parameters can be handled analogously. Example: railroad gate controller We consider the railroad gate controller from Figures 17 and 19 of [6]. The controller, modeled by the automaton of Figure 11, lowers and raises a gate at a railroad crossing. Whenever it detects the presence of an oncoming train, it closes the gate after 5 time units, as measured with the local clock x. The clock is subject to 10 drift, and thus the gate may be ....

R. Alur, T. A. Henzinger, and P. W. Kopke. Real-time system = discrete system + clock variables. Software Tools for Technology Transfer, 1(1), 1997.

.... near d Gamma100 Gamma50 d Gamma35 d = Gamma100 train leaves d = 1000 train present approaching d 1000 d : 5000 Gamma55 d Gamma45 far d = 5000 Figure 12: Train automaton Example: railroad gate controller We consider the railroad gate controller from Figures 17 and 19 of [6]. The controller, modeled by the automaton of Figure 11, lowers and raises a gate at a railroad crossing. Whenever it detects the presence of an oncoming train, it closes the gate after 5 time units, as measured with the local clock x. The clock is subject to 10 drift, and thus the gate may be ....

R. Alur, T. A. Henzinger, and P. W. Kopke. Real-time system = discrete system + clock variables. Software Tools for Technology Transfer, 1(1), 1997.

....time deterministic systems, we can omit the subscripts f i from the next relation 7 . The run ae diverges if ae is infinite and the infinite sum P i0 t i diverges. The hybrid system H is nonzeno if every finite run of H is a prefix of some divergent run of H . Nonzeno systems can be executed [AH94] Hybrid systems as transition systems With the hybrid system H , we associate the labeled transition system TH = Sigma; Lab [ R 0 ; where the step relation is the union of the transition step relations a , for a 2 Lab, a; 0 ) 2 Edg ( 0 ) 2 ; 0 2 Inv( ....

R. Alur and T.A. Henzinger. Real-time system = discrete system + clock variables. In T. Rus, editor, Proceedings of the First AMAST Workshop on Real-time Systems, to appear. Available as Technical Report CSD-TR-94-1403, Cornell University, January 1994.

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC