A simple algorithm for clock synchronization in transputer networks

In a distributed system based on Transputer components there is one clock for each processing element, and the definition of the global system time requires the choice of a hardware or software synchronization method. This paper describes the RING_SYNC algorithm, based on a ring-structured synchronization scheme. RING_SYNC has no provision for fault tolerance, but it introduces little overhead, thanks to the optimization of both the number of messages exchanged at sync time and the resynchronization frequency. The implementation of the algorithm together with the tests performed for measuring the synchronization error and their results are discussed extensively, and some typical applications are pointed out.     

Reverse engineering: Algorithms for program graph production

The paper proposes an algebraic representation of program modules, called F(p), and illustrates the algorithms that use F(p) to generate program graph models for measurement, documentation and testing activities. The representation refers to procedural languages, D-structured programs and one-in/one-out modules but its definition can be extended to programs structured in terms of an arbitrary set of one-in/one-out legal control structures. Since it is possible to produce F(p) directly from the program code using reverse engineering techniques, the algorithms proposed are of considerable interest for the setting up of tools supporting the program comprehension phase, which is a fundamental first step in any maintenance operation.     

Computational proteomics on the grid

The large number of protein sequences, provided by genomic projects at an increasing pace, constitutes a challenge for large scale computational studies of protein structure and thermodynamics. Grid technology is very suitable to face this challenge, since it provides a way to access the resources needed in compute and data intensive applications. In this work, we concentrate on the grid-aware implementation of a protein structure prediction algorithm.     

A homogenized constitutive law for periodic composite materials with elasto-plastic components

The present paper describes how to derive and to apply a homogenised constitutive law for composite materials with periodic structure and elastoplastic components. This method is currently restricted to plane problems with monotonic proportional loading. Within such a framework it seems possible to extend the method to components governed by other non-linear constitutive laws satisfying the complementarity condition.     

A specification-based approach to concurrency analysis

The behavior of a concurrent program often depends on the arbitrary interleaving of computations performed by asynchronous processes. The resulting non-determinism can lead to such phenomena as deadlock and starvation, making program development extremely difficult, and consequently making the development of tools for formal analysis highly desirable.A specification-based approach to concurrency analysis is a particularly promising way of addressing some of the difficulties inherent in concurrent program development. According to this approach, a programmer first writes a specification describing the interprocess communication behavior of a concurrent program. A set of formal analysis techniques are then applied in an effort to determine whether the specification can be fully satisfied. If the analysis is successful, target code is generated automatically that conforms to the specification.This approach has a variety of benefits. While such properties as safety and liveness are rather difficult to discern in actual code, they are actually easy to include as part of a specification. Moreover, state spaces induced by specifications tend to be smaller and more manageable than state spaces of actual code, and this leads to more effective analysis techniques. Finally, the generation of interprocess communication code from formal specifications is accomplished in a relatively straightforward manner.Research partially supported by NSF grant CCR-9109231.     

Fresh water production by means of solar concentration: the AQUASOLIS project

In 2006, the European Commission approved the specific support action (SSA) “AQUASOLIS” as an instrument for assessing the use of solar trough concentration plants for applications other than heating and cooling, in particular for the production of fresh water for human consumption and for agriculture for Mediterranean countries. The capability of solar trough plants of producing heat at temperatures over ca. 150° permits indeed to envisage the use of solar energy for water purification by distillation. At the same time the high temperature fluid generated by the plant can be used to drive adsorption chillers that can extract water from the atmosphere. The AQUASOLIS project was performed as a parallel investigation to the STREP project REACt which is aimed at the actual development of a heating/cooling solar trough system for Mediterranean countries. The results obtained in the AQUASOLIS project show a high promise of the system to help alleviate the conditions of drought in Mediterranean countries and at the same time boosting the use of renewable energy.     

Equivalent circuit characterization of resonant magnetic coupling for wireless transmission of electrical energy

This paper provides the accurate characterization of a wireless power transfer system consisting of two resonant air‐core coils mutually coupled in free space. The lumped‐circuit parameters of the equivalent circuit are determined with analytical formulas taken from the literature and validated by comparison with numerical simulations with a finite‐element computer code and with experiments. The parameters are determined taking as input only the geometry of the system (coil size and mutual distance, conductor radius, and turn distance) and the frequency. Once the lumped‐circuit parameters are known with good accuracy, the assessment of the power transfer system can be carried out by evaluating the current and voltage gains and efficiency for different system geometries, operating frequencies and load conditions. The Scilab programming environment was used to perform all the calculations. The characterization presented in this paper can then be considered as an effective tool in designing an efficient wireless power system. Copyright © 2012 John Wiley & Sons, Ltd.     

Pilot study for MDF manufacture from sugarcane bagasse and eucalyptus fibers

As an innovation in scientific research and development of a new product and with the objective of adding value to sugarcane bagasse, laboratory panels were made with 0%, 25%, 50%, 75% and 100% particles from Saccharum spp bagasse mixed with Eucalyptus grandis fibers, a?raw material traditionally used for MDF panels in Brazil. The physical and mechanical properties of the panels were evaluated according to EN 622-5 (1997). The results indicated that panels with up to 75% bagasse showed average physical and mechanical property values that meet the current specification, thus opening up the prospect of using this abundant agricultural fiber resource.     

Durable CD8 T Cell Memory against SARS-CoV-2 by Prime/Boost and Multi-Dose Vaccination: Considerations on Inter-Dose Time Intervals

Facing the COVID-19 pandemic, anti-SARS-CoV-2 vaccines were developed at unprecedented pace, productively exploiting contemporary fundamental research and prior art. Large-scale use of anti-SARS-CoV-2 vaccines has greatly limited severe morbidity and mortality. Protection has been correlated with high serum titres of neutralizing antibodies capable of blocking the interaction between the viral surface protein spike and the host SARS-CoV-2 receptor, ACE-2. Yet, vaccine-induced protection subsides over time, and breakthrough infections are commonly observed, mostly reflecting the decay of neutralizing antibodies and the emergence of variant viruses with mutant spike proteins. Memory CD8 T cells are a potent weapon against viruses, as they are against tumour cells. Anti-SARS-CoV-2 memory CD8 T cells are induced by either natural infection or vaccination and can be potentially exploited against spike-mutated viruses. We offer here an overview of current research about the induction of anti-SARS-CoV-2 memory CD8 T cells by vaccination, in the context of prior knowledge on vaccines and on fundamental mechanisms of immunological memory. We focus particularly on how vaccination by two doses (prime/boost) or more (boosters) promotes differentiation of memory CD8 T cells, and on how the time-length of inter-dose intervals may influence the magnitude and persistence of CD8 T cell memory.