FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W24506189> ?p ?o ?g. }

• W24506189 abstract "In higher-order process calculi the values exchanged in communications may contain processes. We describe a study of the expressive power of strictly higher-order process calculi, i.e. calculi in which only process passing is allowed and no name-passing is present. In this setting, the polyadicity (i.e. the number of parameters) allowed in communications is shown to induce a hierarchy of calculi of strictly increasing expressiveness: a higher-order calculus with n-adic communication cannot be encoded into a calculus with n − 1-adic communication. In this note we outline this result, and discuss the conditions under which it holds. Introduction. Higher-order process calculi are formal languages for concurrency in which processes can be communicated. They have been put forward in the early 1990s, with CHOCS [1] and Plain CHOCS [2], the Higher-Order π-calculus [3], and others. Recent proposals of higher-order calculi include the Kell calculus [4] and Homer [5]. Higher-order, or process-passing, concurrency is often presented as an alternative paradigm to the first order, or name-passing, concurrency of the π-calculus for the description of mobile systems. Higher-order calculi are inspired by, and are formally closer to, the λ-calculus, whose basic computational step — β-reduction — involves term instantiation. An important criterion for assessing the significance of a paradigm is its expressiveness. The expressiveness of higher-order communication has received little attention in the literature; previous works are mostly concerned about issues of relative expressiveness between higherand first-order calculi. A good example is [6] in which a tight correspondence between name-passing calculi based on internal mobility and processpassing calculi is shown. In a previous work, we have studied expressiveness and decidability issues for HOCORE, a core calculus for higher order concurrency [7]. HOCORE is a strictly higher-order process calculus, in that only the operators necessary to obtain higher-order communications are retained. Notably, no name-passing features are present. The grammar of HOCORE is: P ::= a(x).P | aP | P ‖ P | x | 0 An input prefixed process a(x).P can receive on name (or channel) a a process that will be substituted in the place of x in the body P ; an output message aP can send P on ? Research partially supported by the INRIA Equipe Associee BACON. a; parallel composition allows processes to interact. HOCORE is minimal in that continuations following output messages have been left out (i.e. communication is asynchronous) and, more importantly, it has no restriction operator. Thus all channels are global, and dynamic creation of new channels is impossible. This makes the absence of recursion also relevant, as known encodings of fixed-point combinators in higher-order process calculi require the restriction operator. Despite this minimality, HOCORE was shown to be Turing complete. Therefore, in HOCORE, properties such as termination (i.e. non existence of divergent computations) and convergence (i.e. existence of a terminating computation) are both undecidable. In contrast, somewhat surprisingly, strong bisimilarity is decidable, and several sensible bisimilarities in the higher-order setting coincide with it. A recent work [8] has studied a fragment of HOCORE in which output actions have limited capabilities over previously received processes. In such a fragment, similarly as in HOCORE, convergence is undecidable but, unlike HOCORE, termination is decidable. This Work. In this note we continue our study of the fundamental properties of higherorder process calculi. We shall analyze the consequences that polyadicity (i.e. the number of parameters in higher-order communications) has on the expressiveness of this kind of calculi. We consider variants of HOCORE with different degrees of polyadicity, and study their relative expressive power. Our main result is a hierarchy of calculi of strictly increasing expressiveness: a higher-order process calculus with n-adic communication cannot be encoded into a calculus with n − 1-adic communication. In the remainder, as a way of introducing the peculiarities of the higher-order setting, we discuss the classic encoding of polyadic first-order communication into monadic one; then, we comment on a notion of encoding with a refined account of internal communications. Our result depends critically on this notion. We conclude by giving intuitions on the proof of the main result; more details can be found in [9]. Our Setting. We recall the encoding of the polyadic π-calculus into the monadic one in [10]: [[x(z1, . . . , zn).P ]] = x(w).w(z1). · · · .w(zn). [[P ]] [[x〈a1, . . . , an〉.P ]] = νw xw.wa1. · · · .wan. [[P ]] (where [[·]] is an homomorphism for the other operators). A single n-adic synchronization is encoded as n + 1 monadic synchronizations. The first such synchronizations establishes a private link w: the encoding of output creates a private name w and sends it to the encoding of input. In other words, by virtue of the synchronization on x, private name w is now shared, and its scope is extruded. As a result, name w can be used to communicate each of a1, . . . , an through (monadic) synchronizations. This encoding is very intuitive, and satisfies a tight operational correspondence property: a public synchronization of the source term (i.e. a synchronization on an unrestricted name such as x) is matched by the encoding with a public synchronization on the same name that is followed by a number of internal synchronizations (i.e. synchronizations on a private name such as w). The observable behavior is thus preserved: the encoding does not perform visible actions different from those performed by the" @default.
• W24506189 created "2016-06-24" @default.
• W24506189 creator A5013605827 @default.
• W24506189 creator A5030878839 @default.
• W24506189 creator A5034548013 @default.
• W24506189 creator A5077030456 @default.
• W24506189 date "2009-01-01" @default.
• W24506189 modified "2023-09-27" @default.
• W24506189 title "On the Expressiveness of Polyadicity in Higher-Order Process Calculi (Extended Abstract)" @default.
• W24506189 cites W1523525039 @default.
• W24506189 cites W1530882603 @default.
• W24506189 cites W1542888066 @default.
• W24506189 cites W1789929464 @default.
• W24506189 cites W1790031272 @default.
• W24506189 cites W1998827035 @default.
• W24506189 cites W2001299902 @default.
• W24506189 cites W2060992753 @default.
• W24506189 cites W2094935854 @default.
• W24506189 cites W2098401737 @default.
• W24506189 cites W67262547 @default.
• W24506189 hasPublicationYear "2009" @default.
• W24506189 type Work @default.
• W24506189 sameAs 24506189 @default.
• W24506189 citedByCount "0" @default.
• W24506189 crossrefType "journal-article" @default.
• W24506189 hasAuthorship W24506189A5013605827 @default.
• W24506189 hasAuthorship W24506189A5030878839 @default.
• W24506189 hasAuthorship W24506189A5034548013 @default.
• W24506189 hasAuthorship W24506189A5077030456 @default.
• W24506189 hasConcept C10138342 @default.
• W24506189 hasConcept C161771561 @default.
• W24506189 hasConcept C162324750 @default.
• W24506189 hasConcept C182306322 @default.
• W24506189 hasConcept C193702766 @default.
• W24506189 hasConcept C195818886 @default.
• W24506189 hasConcept C199343813 @default.
• W24506189 hasConcept C199360897 @default.
• W24506189 hasConcept C2777686260 @default.
• W24506189 hasConcept C31170391 @default.
• W24506189 hasConcept C34447519 @default.
• W24506189 hasConcept C41008148 @default.
• W24506189 hasConcept C71924100 @default.
• W24506189 hasConcept C80444323 @default.
• W24506189 hasConcept C98045186 @default.
• W24506189 hasConceptScore W24506189C10138342 @default.
• W24506189 hasConceptScore W24506189C161771561 @default.
• W24506189 hasConceptScore W24506189C162324750 @default.
• W24506189 hasConceptScore W24506189C182306322 @default.
• W24506189 hasConceptScore W24506189C193702766 @default.
• W24506189 hasConceptScore W24506189C195818886 @default.
• W24506189 hasConceptScore W24506189C199343813 @default.
• W24506189 hasConceptScore W24506189C199360897 @default.
• W24506189 hasConceptScore W24506189C2777686260 @default.
• W24506189 hasConceptScore W24506189C31170391 @default.
• W24506189 hasConceptScore W24506189C34447519 @default.
• W24506189 hasConceptScore W24506189C41008148 @default.
• W24506189 hasConceptScore W24506189C71924100 @default.
• W24506189 hasConceptScore W24506189C80444323 @default.
• W24506189 hasConceptScore W24506189C98045186 @default.
• W24506189 hasLocation W245061891 @default.
• W24506189 hasOpenAccess W24506189 @default.
• W24506189 hasPrimaryLocation W245061891 @default.
• W24506189 hasRelatedWork W11313877 @default.
• W24506189 hasRelatedWork W1512907015 @default.
• W24506189 hasRelatedWork W1722539034 @default.
• W24506189 hasRelatedWork W1934020168 @default.
• W24506189 hasRelatedWork W1940075790 @default.
• W24506189 hasRelatedWork W1994932854 @default.
• W24506189 hasRelatedWork W2008838944 @default.
• W24506189 hasRelatedWork W2022079507 @default.
• W24506189 hasRelatedWork W2042757132 @default.
• W24506189 hasRelatedWork W2063961659 @default.
• W24506189 hasRelatedWork W2085354791 @default.
• W24506189 hasRelatedWork W2383517551 @default.
• W24506189 hasRelatedWork W2525817192 @default.
• W24506189 hasRelatedWork W2594012516 @default.
• W24506189 hasRelatedWork W30183370 @default.
• W24506189 hasRelatedWork W3115308655 @default.
• W24506189 hasRelatedWork W3159799407 @default.
• W24506189 hasRelatedWork W67115578 @default.
• W24506189 hasRelatedWork W180422813 @default.
• W24506189 hasRelatedWork W3097395052 @default.
• W24506189 isParatext "false" @default.
• W24506189 isRetracted "false" @default.
• W24506189 magId "24506189" @default.
• W24506189 workType "article" @default.