×

zbMATH — the first resource for mathematics

Conditions of contracts for separating responsibilities in heterogeneous systems. (English) Zbl 1390.68442
Summary: A general, compositional, and component-based contract theory is proposed for modeling and specifying heterogeneous systems, characterized by consisting of parts from different domains, e.g. software, electrical and mechanical. Given a contract consisting of assumptions and a guarantee, clearly separated conditions on a component and its environment are presented where the conditions ensure that the guarantee is fulfilled – a responsibility assigned to the component, given that the environment fulfills the assumptions. The conditions are applicable whenever it cannot be ensured that the sets of ports of components are partitioned into inputs and outputs, and hence fully support scenarios where components, characterized by both causal and acausal models, are to be integrated by solely relying on the information of a contract. An example of such a scenario of industrial relevance is explicitly considered, namely a scenario in a supply chain where the development of a component is outsourced. To facilitate the application of the theory in practice, necessary properties of contracts are also derived to serve as sanity checks of the conditions. Furthermore, based on a graph that represents a structuring of a hierarchy of contracts, sufficient conditions to achieve compositionality are presented.
MSC:
68Q60 Specification and verification (program logics, model checking, etc.)
Software:
MOCHA; Modelica; SysML
PDF BibTeX XML Cite
Full Text: DOI
References:
[1] Meyer, B, Applying “design by contract”, IEEE Comput, 25, 40-51, (1992)
[2] Hoare, CAR, An axiomatic basis for computer programming, Commun ACM, 12, 576-580, (1969) · Zbl 0179.23105
[3] Benveniste, A; etal.; Boer, FS (ed.); etal., Multiple viewpoint contract-based specification and design, 200-225, (2008), Berlin · Zbl 1209.68120
[4] Benveniste, A; Caillaud, B; Passerone, R; Nicolescu, G (ed.); Mosterman, P (ed.), Multi-viewpoint state machines for rich component models, 487-518, (2009), Boca Raton
[5] Sangiovanni-Vincentelli, A L; Damm, W; Passerone, R, Taming Dr. frankenstein: contract-based design for cyber-physical systems, Eur J Control, 18, 217-238, (2012) · Zbl 1264.93152
[6] SPEEDS (2006-2009) SPEculative and exploratory design in systems engineering. http://www.speeds.eu.com/
[7] Henzinger, T; Sifakis, J, The discipline of embedded systems design, Computer, 40, 32-40, (2007)
[8] Lee E (2008) Cyber physical systems: design challenges. In: 11th IEEE international symposium on object oriented real-time distributed computing (ISORC), pp 363-369
[9] Rawat D B, Rodrigues J J, Stojmenovic I (2015) Cyber-physical systems: from theory to practice. CRC Press, Boca Raton
[10] Baumgart A et al (2011) A model-based design methodology with contracts to enhance the development process of safety-critical systems. In: Software technologies for embedded and ubiquitous systems. Volume 6399 of Lecture Notes in Computer Science. Springer, Berlin, pp 59-70 · Zbl 0179.23105
[11] Damm W, Josko B, Peikenkamp T (2009) Contract based ISO CD 26262 safety analysis. In: SAE Technical Paper. SAE International. doi:10.4271/2009-01-0754
[12] Damm W, Hungar H, Josko B, Peikenkamp T, Stierand I (2011) Using contract-based component specifications for virtual integration testing and architecture design. In: 2011 Design, automation test in Europe. DATE’11, pp 1-6. doi:10.1109/DATE.2011.5763167
[13] Westman J, Nyberg M (September 2013) A reference example on the specification of safety requirements using ISO 26262. In: Roy M (ed) Proceedings of workshop DECS (ERCIM/EWICS workshop on dependable embedded and cyber-physical systems) of the 32nd international conference on computer safety, reliability and security, France , p NA · Zbl 0349.68006
[14] Westman J, Nyberg M, Törngren M (2013) Structuring safety requirements in ISO 26262 using contract theory. In: Bitsch F, Guiochet J, Kaniche M (eds) Computer safety, reliability, and security, vol 8153. Lecture Notes in Computer Science. Springer, Berlin, pp 166-177 · Zbl 0299.68013
[15] Westman J, Nyberg M (Jan 2015) Extending contract theory with safety integrity levels. In: IEEE 15th international symposium on high-assurance systems engineering (HASE) 2015. Springer, Berlin · Zbl 0312.68011
[16] Cheng BHC, Atlee JM (2007) Research directions in requirements engineering. In: Future of software engineering, 2007. FOSE ’07. IEEE Computer Society, Washington, DC, pp 285-303. doi:10.1109/FOSE.2007.17 · Zbl 0308.68017
[17] Hull MEC, Jackson K, Dick J (eds) (2011) Requirements engineering, 3rd edn. Springer, New York · Zbl 1204.68200
[18] Zave, P; Jackson, M, Four dark corners of requirements engineering, ACM Trans Softw Eng Methodol, 6, 1-30, (1997)
[19] Fritzson P (2011) Introduction to modeling and simulation of technical and physical systems with Modelica. Wiley, New York
[20] Fritzson P, Engelson V (1998) Modelica—a unified object-oriented language for system modeling and simulation. In: Jul E (ed) ECOO’98—object-oriented programming, vol 1445. Lecture Notes in Computer Science. Springer, Berlin, pp 67-90 · Zbl 0677.68067
[21] Fritzson P (2014) Principles of object-oriented modeling and simulation with modelica 3.3: a cyber-physical approach. Wiley, New York
[22] van Schouwen AJ, Parnas DL, Madey J (Jan 1993) Documentation of requirements for computer systems. In: [1993] Proceedings of the IEEE international symposium on requirements engineering, pp 198-207
[23] Parnas, DL; Madey, J, Functional documents for computer systems, Sci Comput Program, 25, 41-61, (1995)
[24] Liang F et al (2012) Model-based requirement verification : a case study. In: Proceedings of the 9th international Modelica conference, pp 263-268
[25] Schamai W et al (2009) Towards unified system modeling and simulation with ModelicaML: modeling of executable behavior using graphical notations. In: 7th Modelica conference 2009, University Electronic Press · Zbl 1264.93152
[26] Boulanger J-L, Dao VQ (July 2008) Requirements engineering in a model-based methodology for embedded automotive software. In: IEEE international conference on research, innovation and vision for the future, 2008. RIVF 2008, pp 263-268
[27] Friedenthal S, Moore A, Steiner R (2008) A practical guide to SysML: systems modeling language. Morgan Kaufmann Publishers Inc., San Francisco
[28] IEC 61508: Functional safety of electrical/electronic/programmable electronic safety-related systems (2010)
[29] ISO 26262: “Road vehicles-Functional safety” (2011)
[30] Izosimov V, Ingelsson U, Wallin A (2012) Requirement decomposition and testability in development of safety-critical automotive components. In: Ortmeier F, Daniel P (eds) Computer safety, reliability, and security, vol 7612. Lecture Notes in Computer Science. Springer, Berlin, pp 74-86
[31] de Roever W, Langmaack H, Pnueli A (1998) Compositionality: the significant difference. Springer, New York
[32] Hooman J, de Roever WP (1986) The quest goes on: a survey of proofsystems for partial correctness of CSP. In: de Bakker JW, de Roever WP, Rozenberg G (eds) Current trends in concurrency, overviews and tutorials. Springer, Berlin, pp 343-395 · Zbl 0312.68011
[33] Benveniste A et al (November 2012) Contracts for system design. Rapport de recherche RR-8147, INRIA
[34] Abadi, M; Lamport, L, Composing specifications, ACM Trans Program Lang Syst, 15, 73-132, (1993)
[35] Cimatti A, Tonetta S (2015) Contracts-refinement proof system for component-based embedded systems. Sci Comput Program 97(Part 3):333-348. Object-Oriented Programming and Systems (OOPS 2010) Modeling and Analysis of Compositional Software (papers from fEUROMICROg SEAA’12) · Zbl 1210.93068
[36] Negulescu R (2000) Process spaces. In: Proceedings of the 11th international conference on concurrency theory. CONCUR ’00. Springer, London, pp 199-213 · Zbl 0999.68140
[37] Delahaye, B; Caillaud, B; Legay, A, Probabilistic contracts: a compositional reasoning methodology for the design of systems with stochastic and/or non-deterministic aspects, Form. Methods Syst. Des., 38, 1-32, (2011) · Zbl 1210.93068
[38] Sun X et al (July 2009) Contract-based system-level composition of analog circuits. In: Design automation conference, 2009. DAC ’09. 46th ACM/IEEE, pp 605-610 · Zbl 1029.68110
[39] Quinton S, Graf S (Nov. 2008) Contract-based verification of hierarchical systems of components. In: Sixth IEEE international conference on software engineering and formal methods, 2008. SEFM ’08, pp 377-381 · Zbl 0308.68017
[40] Back, R-J; Wright, J, Contracts, games, and refinement, Inf Comput, 156, 25-45, (2000) · Zbl 1046.68571
[41] Goessler G, Raclet J-B (2009) Modal contracts for component-based design. In: Proceedings of the 2009 7th IEEE international conference on software engineering and formal methods. SEFM ’09, Washington, DC, USA. IEEE Computer Society, pp 295-303
[42] Goessler, G; Xu, D; Girault, A, Probabilistic contracts for component-based design, Form Methods Syst Des, 41, 211-231, (2012) · Zbl 1284.68435
[43] Broy M (2011) Towards a theory of architectural contracts: schemes and patterns of assumption/promise based system specification. In: Broy M, Leuxner C, Hoare T (eds) Software and systems safety—specification and verification. NATO Science for Peace and Security Series—D: information and communication security, vol 30. IOP Press, Amsterdam, pp 33-87 · Zbl 0628.68025
[44] Bauer, S; etal.; Lara, J (ed.); Zisman, A (ed.), Moving from specifications to contracts in component-based design, 43-58, (2012), Berlin
[45] Bauer, SS; Hennicker, R; Legay, A, A meta-theory for component interfaces with contracts on ports, Sci Comput Program, 91, 70-89, (2014)
[46] Le, TTH; etal., A tag contract framework for modeling heterogeneous systems, Sci Comput Program, 115, 225-246, (2015)
[47] Maier, P; Orejas, F (ed.); Spirakis, P (ed.); Leeuwen, J (ed.), A set-theoretic framework for assume-guarantee reasoning, 821-834, (2001), Berlin · Zbl 0986.68057
[48] Mcmillan KL (1999) Circular compositional reasoning about liveness. In: Advances in hardware design and verification: IFIP WG10.5 international conference on correct hardware design and verification methods (CHARME 99), vol 1703 of Lecture Notes in Computer Science. Springer, Berlin, pp 342-345 · Zbl 1351.68184
[49] Abadi, M; Lamport, L, Conjoining specifications, ACM Trans Program Lang Syst, 17, 507-535, (1995)
[50] Misra, J; Chandy, K, Proofs of networks of processes, IEEE Trans Softw Eng, SE-7, 417-426, (1981) · Zbl 0468.68030
[51] Cau, A; Collette, P, Parallel composition of assumption-commitment specifications, Acta Inf, 33, 153-176, (1996) · Zbl 0837.68025
[52] Xu, Q; Cau, A; Collette, P; Jonsson, B (ed.); Parrow, J (ed.), On unifying assumption-commitment style proof rules for concurrency, 267-282, (1994), Berlin
[53] Viswanathan, M; Viswanathan, R; Orejas, F (ed.); Spirakis, P (ed.); Leeuwen, J (ed.), Foundations for circular compositional reasoning, 835-847, (2001), Berlin · Zbl 0986.68059
[54] Tsay, Y-K; Tiuryn, J (ed.), Compositional verification in linear-time temporal logic, 344-358, (2000), Berlin · Zbl 0961.68093
[55] Amla, N; etal.; Amadio, R (ed.); Lugiez, D (ed.), Abstract patterns of compositional reasoning, 431-445, (2003), Berlin · Zbl 1274.68217
[56] Chilton, C; Jonsson, B; Kwiatkowska, M, An algebraic theory of interface automata, Theor Comput Sci, 549, 146-174, (2014) · Zbl 1360.68608
[57] Tripakis, S; etal., A theory of synchronous relational interfaces, ACM Trans Program Lang Syst, 33, 14:1-14:41, (2011)
[58] Alur, R; Henzinger, T, Reactive modules, Form Methods Syst Des, 15, 7-48, (1999)
[59] Grumberg, O; Long, DE, Model checking and modular verification, ACM Trans Program Lang Syst, 16, 843-871, (1994)
[60] Davis M (1961) Infinite games with perfect information. University of California, Berkeley
[61] Dill DL (1988) Trace theory for automatic hierarchical verification of speed-independent circuits. In: Proceedings of the fifth MIT conference on Advanced research in VLSI. MIT Press, Cambridge, pp 51-65 · Zbl 0468.68030
[62] Wolf ES (1996) Hierarchical models of synchronous circuits for formal verification and substitution. PhD thesis, Stanford University, Stanford, CA, USA UMI Order No. GAX96-12052
[63] Brookes, SD; Hoare, CAR; Roscoe, AW, A theory of communicating sequential processes, J ACM, 31, 560-599, (1984) · Zbl 0628.68025
[64] Westman, J; Nyberg, M; Dingel, J (ed.); etal., Environment-centric contracts for design of cyber-physical systems, No. 8767, 218-234, (2014), Berlin
[65] Simko G et al (2014) Towards a theory for cyber-physical systems modeling. In: Proceedings of the 4th ACM SIGBED international workshop on design, modeling, and evaluation of cyber-physical systems. CyPhy ’14. ACM, New York, pp 56-61
[66] Lamport, L, A simple approach to specifying concurrent systems, Commun ACM, 32, 32-45, (1989)
[67] Abadi, M; Lamport, L, The existence of refinement mappings, Theor Comput Sci, 82, 253-284, (1991) · Zbl 0728.68083
[68] Josko B, Ma Q, Metzner A (01 2008) Designing embedded systems using heterogeneous rich components. In: Proceedings of the INCOSE international symposium 2008
[69] Damm W (June 2005) Controlling speculative design processes using rich component models. In: . Fifth international conference on application of concurrency to system design, 2005. ACSD 2005, pp 118-119
[70] Westman J, Nyberg M, Gustavsson J, Gurov D (2017) Formal architecture modeling of sequential non-recursive C programs. Sci Comput Program 146:2-27 · Zbl 1284.68435
[71] Gacek, A; etal.; Havelund, K (ed.); Holzmann, G (ed.); Joshi (ed.), Towards realizability checking of contracts using theories, 173-187, (2015), Berlin
[72] Le TTH, Passerone R (Oct 2014) Refinement-based synthesis of correct contract model decompositions. In: 2014 Twelfth ACM/IEEE international conference on formal methods and models for Codesign (MEMOCODE), pp 134-143
[73] Roever, W-P; Roever, W-P (ed.); Langmaack, H (ed.); Pnueli, A (ed.), The need for compositional proof systems: a survey, 1-22, (1998), Berlin
[74] Yu E (Jan 1997) Towards modelling and reasoning support for early-phase requirements engineering. In: Proceedings of the third IEEE international symposium on requirements engineering, 1997, pp 226-235
[75] Lamsweerde, A; Letier, E; Wirsing, M (ed.); Knapp, A (ed.); Balsamo, S (ed.), From object orientation to goal orientation: a paradigm shift for requirements engineering, 325-340, (2004), Berlin
[76] Lapouchnian A (205) Goal-oriented requirements engineering: an overview of the current research. Technical report, University of Toronto
[77] Jackson M (1995) The world and the machine. In: Proceedings of the 17th international conference on software engineering. ICSE ’95. ACM, New York, pp 283-292
[78] Jackson M (1995) Software requirements and specifications: a lexicon of practice principles and prejudices. ACM Press/Addison-Wesley Publishing Co., New York
[79] Parnas, DL, Functional documents for computer systems, Sci Comput Program, 25, 41-61, (1995)
[80] Nyberg M (Oct 2013) Failure propagation modeling for safety analysis using causal Bayesian networks. In: 2013 Conference on control and fault-tolerant systems (SysTol), pp 91-97 · Zbl 0904.68002
[81] Nyberg M, Westman J (Sept 2015) failure propagation modeling based on contracts theory. In: Dependable computing conference (EDCC), 2015 Eleventh European, pp 108-119 · Zbl 1046.68571
[82] Namjoshi, KS; Trefler, RJ, On the completeness of compositional reasoning methods, ACM Trans Comput Logic, 11, 1-22, (2010) · Zbl 1351.68184
[83] Maier, P; Gordon, A (ed.), Compositional circular assume-guarantee rules cannot be sound and complete, 343-357, (2003), Berlin · Zbl 1029.68110
[84] Doyen L et al (2008) Interface theories with component reuse. In: Proceedings of the 8th ACM international conference on embedded software. EMSOFT ’08. ACM, New York, pp 79-88
[85] Giese H (2000) Contract-based component system design. In: Thirty-third annual Hawaii international conference on system sciences (HICSS-33). IEEE Press, Maui
[86] Sun X (May 2011) Compositional design of analog systems using contracts. PhD thesis, EECS Department, University of California, Berkeley · Zbl 1029.68110
[87] Bliudze S, Sifakis J (2007) The algebra of connectors: structuring interaction in BIP. In: Proceedings of the 7th ACM and IEEE international conference on embedded software. EMSOFT ’07. ACM, New York, pp 11-20 · Zbl 1390.68031
[88] Back R-JJ, Akademi A, Wright JV (1998) Refinement calculus: a systematic introduction, 1st edn. Springer, New York · Zbl 0949.68094
[89] Graf S, Quinton S (2007) Contracts for BIP: hierarchical interaction models for compositional verification. In: Proceedings of the 27th IFIP WG 6.1 international conference on formal techniques for networked and distributed systems. FORTE ’07. Springer, Berlin, pp 1-18 · Zbl 1215.68028
[90] Cimatti A, Dorigatti M, Tonetta S (Nov 2013) OCRA: a tool for checking the refinement of temporal contracts. In: 2013 IEEE/ACM 28th international conference on automated software engineering (ASE), pp 702-705
[91] Derler P et al (2013) Cyber-physical system design contracts. In: ICCPS ’13: ACM/IEEE 4th international conference on cyber-physical systems
[92] Törngren M et al (Aug 2012) Design contracts for cyber-physical systems: making timing assumptions explicit. Technical Report UCB/EECS-2012-191, EECS Department, University of California, Berkeley
[93] Ruchkin I et al. (2014) Contract-based integration of cyber-physical analyses. In: Proceedings of the 14th international conference on embedded software. EMSOFT ’14. ACM, New York, pp 23:1-23:10
[94] Bate I, Hawkins R, McDermid J (2003) A contract-based approach to designing safe systems. In: Proceedings of the 8th Australian workshop on safety critical system and software, vol 33. SCS ’03, Australian Computer Society, Inc., pp 25-36
[95] Arts, T; Dorigatti, M; Tonetta, S; Bondavalli, A (ed.); Giandomenico, F (ed.), Making implicit safety requirements explicit, 81-92, (2014), Berlin
[96] Soderberg A, Johansson R (Nov 2013) Safety contract based design of software components. In: 2013 IEEE international symposium on software reliability engineering workshops (ISSREW), pp 365-370
[97] Soderberg A, Vedder B (Nov 2012) Composable safety-critical systems based on pre-certified software components. In: 2012 IEEE 23rd international symposium on software reliability engineering workshops (ISSREW), pp 343-348 · Zbl 0517.68032
[98] Larsen, KG; Sifakis, J (ed.), Modal specifications, 232-246, (1990), Berlin
[99] David A et al (2010) Timed I/O automata: a complete specification theory for real-time systems. In: Proceedings of the 13th ACM international conference on hybrid systems: computation and control. HSCC ’10. ACM, New York, pp 91-100 · Zbl 1361.68143
[100] Raclet, J-B; etal., A modal interface theory for component-based design, Fundam Inf, 108, 119-149, (2011) · Zbl 1242.68147
[101] Alfaro, L; Henzinger, TA, Interface automata, SIGSOFT Softw Eng Notes, 26, 109-120, (2001)
[102] Lynch, NA; Tuttle, MR, An introduction to input/output automata, CWI Q, 2, 219-246, (1989) · Zbl 0677.68067
[103] Chilton C, Jonsson B, Kwiatkowska M (2014) Compositional assumeguarantee reasoning for input/output component theories. Sci Comput Program 91(Part A):115-137. Special Issue on Formal Aspects of Component Software (Selected Papers from FACS12)
[104] Jones CB (September 1983) Specification and design of (parallel) programs. In: Mason REA (ed) Information processing 83. Volume 9 of IFIP Congress Series. Paris, France, IFIP, North-Holland, pp 321-332
[105] Jones, CB, Tentative steps toward a development method for interfering programs, ACM Trans Program Lang Syst, 5, 596-619, (1983) · Zbl 0517.68032
[106] Floyd RW (1967) Assigning meanings to programs. In: Schwartz JT (ed) Mathematical aspects of computer science. Volume 19 of proceedings of symposia in applied mathematics. American Mathematical Society, Providence, pp 19-32
[107] Dijkstra, EW, Guarded commands, nondeterminacy and formal derivation of programs, Commun ACM, 18, 453-457, (1975) · Zbl 0308.68017
[108] Owicki, S; Gries, D, An axiomatic proof technique for parallel programs I, Acta Inf, 6, 319-340, (1976) · Zbl 0312.68011
[109] Ashcroft, EA, Proving assertions about parallel programs, J Comput Syst Sci, 10, 110-135, (1975) · Zbl 0299.68013
[110] Lamport, L, Proving the correctness of multiprocess programs, IEEE Trans Softw Eng, 3, 125-143, (1977) · Zbl 0349.68006
[111] Pnueli, A; Apt, K (ed.), In transition from global to modular temporal reasoning about programs, 123-144, (1985), Berlin
[112] Alur, R; etal.; Hu, A (ed.); Vardi, M (ed.), MOCHA: modularity in model checking, 521-525, (1998), Berlin
[113] Gurov, D; Huisman, M; Sprenger, C, Compositional verification of sequential programs with procedures, Inf Comput, 206, 840-868, (2008) · Zbl 1153.68036
[114] Kupferman, O; Vardi, MY, An automata-theoretic approach to modular model checking, ACM Trans Program Lang Syst, 22, 87-128, (2000) · Zbl 1133.68376
[115] Păsăreanu, CS; etal., Learning to divide and conquer: applying the L* algorithm to automate assume-guarantee reasoning, Form Methods Syst Des, 32, 175-205, (2008) · Zbl 1147.68053
[116] Cobleigh, JM; Avrunin, GS; Clarke, LA, Breaking up is hard to do: an evaluation of automated assume-guarantee reasoning, ACM Trans Softw Eng Methodol, 17, 7:1-7:52, (2008)
[117] Jonsson, B; Yih-Kuen, T, Assumption/guarantee specifications in linear-time temporal logic, Theor Comput Sci, 167, 47-72, (1996) · Zbl 0874.68210
[118] Broy, M, Compositional refinement of interactive systems, J ACM, 44, 850-891, (1997) · Zbl 0904.68002
[119] Broy M, Stølen K (2001) Specification and development of interactive systems: focus on streams, interfaces, and refinement. Springer, New York · Zbl 0981.68115
[120] Hammond J, Rawlings R, Hall A (2001) Will it work? [Requirements engineering]. In: Proceedings. Fifth IEEE international symposium on requirements engineering, 2001, pp 102-109
[121] Cofer D et al (2012) Compositional verification of architectural models. In: Proceedings of the 4th international conference on NASA formal methods. NFM’12. Springer, Berlin, pp 126-140 · Zbl 0904.68002
[122] Persson M et al (2013) A characterization of integrated multi-view modeling in the context of embedded and cyber-physical systems. In: Proceedings of the eleventh ACM international conference on embedded software. EMSOFT ’13. IEEE Press, Piscataway, pp 10:1-10:10 · Zbl 0677.68067
[123] Törngren M et al (2014) Integrating viewpoints in the development of mechatronic products. Mechatronics 24(7):745-762 1. Model-Based Mechatronic System Design 2. Model Based Engineering
[124] Lee, E; Sangiovanni-Vincentelli, A, A framework for comparing models of computation, IEEE Trans Comput Aided Des Integr Circuits Syst, 17, 1217-1229, (1998)
[125] Alfaro, L; Henzinger, TA; Henzinger, TA (ed.); Kirsch, CM (ed.), Interface theories for component-based design, 148-165, (2001), Berlin · Zbl 1050.68518
[126] Passerone R (2004) Semantic foundations for heterogeneous systems. PhD thesis, University of California, Berkeley AAI3146975 · Zbl 0299.68013
[127] Burch J, Passerone R, Sangiovanni-Vincentelli A (2001) Overcoming heterophobia: modeling concurrency in heterogeneous systems. In: Proceedings. 2001 international conference on application of concurrency to system design, 2001, pp 13-32
[128] Engelfriet, J, Determinancy (observation equivalence = trace equivalence), Theor Comput Scie, 36, 21-25, (1985) · Zbl 0571.68018
[129] Milner R (1982) A calculus of communicating systems. Springer, New York · Zbl 0452.68027
[130] Alur R et al (1998) Alternating refinement relations. In: In Proceedings of the ninth international conference on concurrency theory (CONCUR98), volume 1466 of LNCS. Springer, Berlin, pp 163-178 · Zbl 1070.68524
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. It attempts to reflect the references listed in the original paper as accurately as possible without claiming the completeness or perfect precision of the matching.