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Undecidable problems in unreliable computations

Richard Mayr
2003 Theoretical Computer Science  
Lossy counter machines can be used as a general tool to prove the undecidability of many problems, for example: (1) The veriÿcation of systems that model communication through unreliable channels (e.g.  ...  Lossy counter machines are deÿned as Minsky counter machines where the values in the counters can spontaneously decrease at any time.  ...  (In a di erent framework this corresponds to lost messages in unreliable communication channels.) There are many di erent kinds of lossiness, i.e., di erent ways in which the counters can decrease.  ... 
doi:10.1016/s0304-3975(02)00646-1 fatcat:bhjxljv6tnagbghaw4gkwzzbau

Undecidable Problems in Unreliable Computations [chapter]

Richard Mayr
2000 Lecture Notes in Computer Science  
Lossy counter machines can be used as a general tool to prove the undecidability of many problems, for example: (1) The veriÿcation of systems that model communication through unreliable channels (e.g.  ...  Lossy counter machines are deÿned as Minsky counter machines where the values in the counters can spontaneously decrease at any time.  ...  (In a di erent framework this corresponds to lost messages in unreliable communication channels.) There are many di erent kinds of lossiness, i.e., di erent ways in which the counters can decrease.  ... 
doi:10.1007/10719839_37 fatcat:x5fixw6irfgq5jxzzox3locts4

On Undecidability Aspects of Resilient Computations and Implications to Exascale [chapter]

Nageswara S. V. Rao
2014 Lecture Notes in Computer Science  
Context of Undecidability 3. Complex Faults in Exascale Systems 4. Decision Problems on Exascale Computations 5. Undecidability of Resilient Computations 6.  ...  , equivalence of contextfree grammar, virus detection problems -Resilient Computations: Certain resilient computational problems turn out to be undecidable Godel's Undecidability: Non-existence of mathematical  ...  proofs of resilience of algorithms are undecidable These problems are not solvable in general form by computations and mathematical proofs alone: but, • resilient computations can be designed for specific  ... 
doi:10.1007/978-3-319-14325-5_44 fatcat:rgslzmfhynaxpicl5jqzntczby

Page 3210 of Mathematical Reviews Vol. , Issue 98E [page]

1998 Mathematical Reviews  
In this paper they prove the undecidability of some ver- ification problems which involve fairness or liveness properties, namely the model checking problem in propositional linear time logic (PTL) and  ...  Gabriel Ciobanu (R-1ASI-C; lasi) 98e:68160 68Q60 03D35 68Q10 Abdulla, Parosh Aziz (S-UPPS-SY; Uppsala); Jonsson, Bengt (S-UPPS-SY; Uppsala) Undecidable verification problems for programs with unreliable  ... 

Unreliable Channels Are Easier to Verify Than Perfect Channels

Gérard Cécé, Alain Finkel, S. Purushothaman Iyer
1996 Information and Computation  
 Others: finite termination, computation of , model-1 But… [BZ83] read the list until end symbol, emit symbol.  Write and go-back are similar.  Every problem of interest is undecidable!  ...   Unreliable Channels  Unreliable channels can:  lose messages, or  duplicate messages, or  insert new messages, or  a combination of all the above.  ... 
doi:10.1006/inco.1996.0003 fatcat:sh4wdy2z6vgerldilkh4dp2vry

Duplication, insertion and lossiness errors in unreliable communication channels

Gérard Cécé, Alain Finkel, S. Purushothaman Iyer
1994 Proceedings of the 2nd ACM SIGSOFT symposium on Foundations of software engineering - SIGSOFT '94  
channels have been used as an abstract model of computation for reasoning about communication protocols [4, 11] and form the backbone of 1S0 protocol specification languages Estelle [8] and SDL [7].  ...  Furthermore, the chan- nel language is not computable and model checking against CTL * is undecidable. 7 Conclusion We summarize the results known to date, on unreliable chan- nels, in  ...  Verifying Programs with Unreliable Channels. In Proc of Logic in Computer Science, 1993. P. AbduUa and B. Jonsson.  ... 
doi:10.1145/193173.195292 dblp:conf/sigsoft/CeceFI94 fatcat:fyf4tincezfrrah4s2q2vdul7i

Undecidable Verification Problems for Programs with Unreliable Channels

Parosh Aziz Abdulla, Bengt Jonsson
1996 Information and Computation  
In this paper, we show that the following problems are undecidable: v The model checking problem in propositional temporal logics such as propositional linear time temporal logic (PTL) and computation  ...  tree logic (CTL). v The problem of deciding eventuality properties with fair channels: do all computations eventually reach a given set of states if the unreliable channels satisfy fairness assumptions  ...  We thank Karlis C 2 eraÄ ns for bringing to our attention the undecidability proof of the Cyclic Post's Correspondence Problem in [Ruo83] .  ... 
doi:10.1006/inco.1996.0083 fatcat:vefnrgyd6ncgfintje4vkq6y2q

Page 1394 of Mathematical Reviews Vol. , Issue 2004b [page]

2004 Mathematical Reviews  
In addition to such basic results, the paper provides a series of suggestions for further research.” 2004b:68048 68Q05 Mayr, Richard (F-PARIS7-FA; Paris) Undecidable problems in unreliable computations  ...  Thus, the range of undecidability results that can be proved by using (unde- cidable problems for) counter machines is extended. In particular, simpler proofs can be given for known results.  ... 

The Validation of the Career Decision-Making Difficulties Scale in a Chinese Culture

Hsiu-Lan Shelley Tien
2005 Journal of Career Assessment  
However, for the undecided students in the process of career decision making, the factors before and during the process were mixed.  ...  The results indicated significant differences between decided and undecided students on their perceptions of career difficulties, Λ(10,464) = .729.  ...  Homogeneity of decided and undecided groups was tested to cope with the problem caused by different cell numbers.  ... 
doi:10.1177/1069072704270327 fatcat:cal3degmtnd4nbuk2ugzssv4wa

Page 1795 of Mathematical Reviews Vol. , Issue 96c [page]

1996 Mathematical Reviews  
Moreover, all these undecidability results hold even for locally unary processes. In the unary case, these problems become decidable. In fact, they are I1$-complete.  ...  In this paper we show that the problem of recogniz- 68Q Theory of computing 96c:68053 ing schedules in this class is NP-complete.  ... 

Reliable Contracts for Unreliable Half-Duplex Communications [chapter]

Étienne Lozes, Jules Villard
2012 Lecture Notes in Computer Science  
Recent trends in formal models of web services description languages and session types focus on the asynchronicity of communications.  ...  We moreover establish a polynomial-time complexity for the analysis of communication contracts under arbitrary models of asynchronicity, and we investigate the model-checking problems against LTL formulas  ...  Problem Does C C satisfy φ? is undecidable if is regular (resp. semi-linear).  ... 
doi:10.1007/978-3-642-29834-9_2 fatcat:ghb3c7fxwffpzlacoltdhyvyga

Unidirectional Channel Systems Can Be Tested [chapter]

Petr Jančar, Prateek Karandikar, Philippe Schnoebelen
2012 Lecture Notes in Computer Science  
Some undecidable problems for UCST[Z Z Z, , , N N N] 7 Theorem 7.1. Recurrent reachability is undecidable for UCST[Z r 1 ].  ...  With other unreliable computational models, lossy channel systems are now an important tool for the complexity analysis of algorithms that rely on well-quasi-ordering theory [17] [18] [19] .  ... 
doi:10.1007/978-3-642-33475-7_11 fatcat:jwajzgjkg5gu7jfyxsyjurv4pm

Page 2889 of Mathematical Reviews Vol. , Issue 2003d [page]

2003 Mathematical Reviews  
In this article we show that these problems cannot be solved in primitive recursive time.” 2003d:68175 68Q60 03B44 20M99 68Q70 Wilke, Thomas (D-KIEL; Kiel) Linear temporal logic and finite semigroups.  ...  (English summary) Theoretical aspects of computer software (Sendai, 2001), 385-399, Lecture Notes in Comput. Sci., 2215, Springer, Berlin, 2001.  ... 

Page 6241 of Mathematical Reviews Vol. , Issue 96j [page]

1996 Mathematical Reviews  
All of these problems are undecidable for machines communicating over reliable unbounded FIFO channels. So it is  ...  We show that any Berry-computable function can be computed in a sequential way by a relative al- gorithm.  ... 

Towards The Use Of Information And Communication Technology In Undergraduates Learning: Possession, Perception And Problems In Obafemi Awolowo University, Ile-Ife, Nigeria

Adeola Oyebisi Egbedokun, Lawunmi Molara Oyewusi
2014 World Journal of Education  
However, they identified lack of power supply, pproblem of access, financial constrains, and phones without MMS capability as problems that might militate against the use of ICT in learning.  ...  It was found that majority of the undergradutes in OAU possess ICT facilities that can be used in learning.  ...  failure was a problem, 6.2% were undecided while 4.2% disagreed. 74% agreed that there are problem with some phones that do not have MMS capabilities, 14.4% were undecided while 11.5% disagreed. 80.5%  ... 
doi:10.5430/wje.v4n2p50 fatcat:yqagwgqh6fa2fb5jnjyxs4h6iq
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