Graphical Encoding of a Spatial Logic for the pi-Calculus

This paper extends our graph-based approach to the verification of spatial properties of π-calculus specifications. The mechanism is based on an encoding for mobile calculi where each process is mapped into a graph (with interfaces) such that the denotation is fully abstract with respect to the usual structural congruence, i.e., two processes are equivalent exactly when the corresponding encodings yield isomorphic graphs. Behavioral and structural properties of π-calculus processes expressed in a spatial logic can then be verified on the graphical encoding of a process rather than on its textual representation. In this paper we introduce a modal logic for graphs and define a translation of spatial formulae such that a process verifies a spatial formula exactly when its graphical representation verifies the translated modal graph formula

Philosophical logics - a survey and a bibliography

Intensional logics attract the attention of researchers from differing academic backgrounds and various scientific interests. My aim is to sketch the philosophical background of alethic, doxastic, and deontic logics, their formal and metaphysical presumptions and their various problems and paradoxes, without attempting formal rigor. A bibliography, concise on philosophical writings, is meant to allow the reader\u27s access to the maze of literature in the field

Gluing together proof environments: Canonical extensions of LF type theories featuring locks

© F. Honsell, L. Liquori, P. Maksimovic, I. Scagnetto This work is licensed under the Creative Commons Attribution License.We present two extensions of the LF Constructive Type Theory featuring monadic locks. A lock is a monadic type construct that captures the effect of an external call to an oracle. Such calls are the basic tool for gluing together diverse Type Theories and proof development environments. The oracle can be invoked either to check that a constraint holds or to provide a suitable witness. The systems are presented in the canonical style developed by the CMU School. The first system, CLLF/p,is the canonical version of the system LLF p, presented earlier by the authors. The second system, CLLF p?, features the possibility of invoking the oracle to obtain a witness satisfying a given constraint. We discuss encodings of Fitch-Prawitz Set theory, call-by-value λ-calculi, and systems of Light Linear Logic. Finally, we show how to use Fitch-Prawitz Set Theory to define a type system that types precisely the strongly normalizing terms

A logic for application level QoS

Service Oriented Computing (SOC) has been proposed as a paradigm to describe computations of applications on wide area distributed systems. Awareness of Quality of Service (QoS) is emerging as a new exigency in both design and implementation of SOC applications. We do not refer to QoS aspects related to low-level performance and focus on those high-level non-functional features perceived by end-users as application dependent requirements, e.g., the price of a given service, or the payment mode, or else the availability of a resource (e.g., a file in a given format). In this paper we present a logic which includes mechanisms to consider the three main dimensions of systems, namely their structure, behaviour and QoS aspects. The evaluation of a formula is a value of a constraint-semiring and not just a boolean value expressing whether or not the formula holds. This permits to express not only topological and temporal properties but also QoS properties of systems. The logic is interpreted on SHReQ, a formal framework for specifying systems that handles abstract high-level QoS aspects combining Synchronised Hyperedge Replacement with constraint-semirings

Behavioral types in programming languages

A recent trend in programming language research is to use behav- ioral type theory to ensure various correctness properties of large- scale, communication-intensive systems. Behavioral types encompass concepts such as interfaces, communication protocols, contracts, and choreography. The successful application of behavioral types requires a solid understanding of several practical aspects, from their represen- tation in a concrete programming language, to their integration with other programming constructs such as methods and functions, to de- sign and monitoring methodologies that take behaviors into account. This survey provides an overview of the state of the art of these aspects, which we summarize as the pragmatics of behavioral types

Octonions and the Triple Articulation

Num artigo anterior descrevemos a nossa abordagem para modelar as relações que um ecossistema de negócios pode sustentar para as demandas multi-facetadas dos seus clientes. Esta abordagem distinguia dois tipos de tempo, chronos e kairos, e era triplamente articulada, descrevendo uma empresa como uma realização de possíveis composições de 'capacidades tecnológicas', 'modelos sociais de orquestração e sincronização' e as antecipações de satisfações ‘da diferenciação das organizações dos clientes individuais'. Este artigo descreve os trabalhos subsequentes que necessitaram abandonar os Números Complexos como sua base matemática em favor dos Quaterniones e finalmente adoptar os Octoniones que fornecem um modelo da trialidade, necessário para abstrair as relações entre as articulações. Identificam-se uma série de questões de pesquisa derivadas da abordagem que fornece um meio para relacionar a agilidade necessária para apoiar uma relação dinâmica entre a situação de um cliente individual e a abordagem adoptada para instituir a empresa como um todo.A previous paper described our approach to modeling the relations that a business ecosystem can sustain to the multi-sided demands of its clients. This approach distinguished two kinds of time, chronos and kairos, and was triply articulated, describing an enterprise as a realization of possible compositions of ‘technological capabilities’, ‘social models of orchestration and synchronization’ and ‘the differing organizations of individual clients' anticipations of satisfaction’. This paper describes subsequent work that necessitated abandoning the Complex Numbers as its mathematical basis in favour of the Quaternions and finally adopting the Octonions which provide a model of triality necessary for abstracting the relations between the articulations. It identifies a number of research questions derived from the approach which provides a means of relating the agility needed to support a dynamic relation to an individual client’s situation with the approach taken to instituting the enterprise as a whole