Actors for the Internet of Things

The actor model is a model for concurrent computation, centered around message passing between entities in a system. It is well suited for distributed programming, due to its semantics including very little guarantees or assumptions of reliability. Actor model implementations have grown more widespread in many languages. The library Akka (written in Scala) is one of the most popular actor libraries. However, Akka is missing some key features. Our goal is to create our own actor library called Aurum, which not only has these features but exhibits higher performance. The new features include easy ways to forge references, configure and launch clusters, message type translations, and the ability to inject message drops and delays into every part the application. Aurum will be implemented in Rust, a programming language designed for high performance, asynchrony and high levels of abstraction that is well suited for IoT devices. Our results show that Aurum outperforms Akka. In our benchmarks, a single server running Aurum gives three times the throughput as an equivalent Akka server, while maintaining good programmability and having features useful for IoT.

Leafy automata for higher-order concurrency

Finitary Idealized Concurrent Algol ($$\mathsf {FICA}$$ FICA ) is a prototypical programming language combining functional, imperative, and concurrent computation. There exists a fully abstract game model of $$\mathsf {FICA}$$ FICA , which in principle can be used to prove equivalence and safety of $$\mathsf {FICA}$$ FICA programs. Unfortunately, the problems are undecidable for the whole language, and only very rudimentary decidable sub-languages are known.We propose leafy automata as a dedicated automata-theoretic formalism for representing the game semantics of $$\mathsf {FICA}$$ FICA . The automata use an infinite alphabet with a tree structure. We show that the game semantics of any $$\mathsf {FICA}$$ FICA term can be represented by traces of a leafy automaton. Conversely, the traces of any leafy automaton can be represented by a $$\mathsf {FICA}$$ FICA term. Because of the close match with $$\mathsf {FICA}$$ FICA , we view leafy automata as a promising starting point for finding decidable subclasses of the language and, more generally, to provide a new perspective on models of higher-order concurrent computation.Moreover, we identify a fragment of $$\mathsf {FICA}$$ FICA that is amenable to verification by translation into a particular class of leafy automata. Using a locality property of the latter class, where communication between levels is restricted and every other level is bounded, we show that their emptiness problem is decidable by reduction to Petri net reachability.

A State of Art Survey for Concurrent Computation and Clustering of Parallel Computing for Distributed Systems

In this paper, several works has been presented related to the clustering parallel computing for distributed system. The trend of the paper is to focus on the strength points of previous works in this field towards enhancing performance of the distributed systems. This concentration conducted via presenting several techniques where each of them has the weak and strong features. The most challenging points for all techniques vary from increasing the performance of the system to time responding to overcome overhead running of the system. For more specific addressing concurrent computation besides parallel computing classifications for distributed systems, this paper depended comprehensive features study and comparison between SYNC and ASYNC Modes.

An Axiomatic Approach to Reversible Computation

Undoing computations of a concurrent system is beneficial in many situations, e.g., in reversible debugging of multi-threaded programs and in recovery from errors due to optimistic execution in parallel discrete event simulation. A number of approaches have been proposed for how to reverse formal models of concurrent computation including process calculi such as CCS, languages like Erlang, prime event structures and occurrence nets. However it has not been settled what properties a reversible system should enjoy, nor how the various properties that have been suggested, such as the parabolic lemma and the causal-consistency property, are related. We contribute to a solution to these issues by using a generic labelled transition system equipped with a relation capturing whether transitions are independent to explore the implications between these properties. In particular, we show how they are derivable from a set of axioms. Our intention is that when establishing properties of some formalism it will be easier to verify the axioms rather than proving properties such as the parabolic lemma directly. We also introduce two new notions related to causal consistent reversibility, namely causal safety and causal liveness, and show that they are derivable from our axioms.

Mathematical simulation of aircraft engine jet exhausts radiation

The paper deals with the problems of mathematical simulation of aircraft engine jet exhausts radiation, the simulation being carried out by means of shader subroutines for the concurrent computation of the radiative transfer equation on the video card resources. The combination of an analytical model of an isobaric jet and ray tracing of computation of the radiative transfer equation allows us to develop a flexible model of aircraft jet radiation, the model taking into account the main parameters of streams in the jet and in the co-current flow, the spectral lines of the radiating components, and provides real-time computation. For the graphic implementation of the model, the OpenGL standard is used