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Boolean network tomography is a powerful tool to infer the state (working/failed) of individual nodes from path-level measurements obtained by edge-nodes. We consider the problem of optimizing the capability of identifying network failures through the design of monitoring schemes. Finding an optimal solution is NP-hard and a large body of work has been devoted to heuristic approaches providing lower bounds. Unlike previous works, we provide upper bounds on the maximum number of identifiable nodes, given the number of monitoring paths and different constraints on the network topology, the routing scheme, and the maximum path length. These upper bounds represent a fundamental limit on identifiability of failures via Boolean network tomography. Our analysis provides insights on how to design topologies and related monitoring schemes to achieve the maximum identifiability under various network settings. Through analysis and experiments we demonstrate the tightness of the bounds and efficacy of the design insights for engineered as well as real networks.

Boolean Network Tomography (BNT) allows to localize network failures by means of end-to-end monitoring paths. Nevertheless, it falls short of providing efficient failure identification in real scenarios, due to the large combinatorial size of the solution space, especially when multiple failures occur concurrently. We aim at maximizing the identification capabilities of a bounded number of monitoring probes. To tackle this problem we propose a progressive approach to failure localization based on stochastic optimization, whose solution is the optimal sequence of monitoring paths to probe. We address the complexity of the problem by proposing a greedy strategy in two variants: one considers exact calculation of posterior probabilities of node failures given the observation, whereas the other approximates these values through a novel failure centrality metric. We discuss the approximation of the proposed approaches. Then, by means of numerical experiments conducted on real network topologies, we demonstrate the practical applicability of our approach. The performance evaluation evidences the superiority of our algorithms with respect to state of the art solutions based on classic Boolean Network Tomography as well as approaches based on sequential group testing.

A Sense and Respond (SaR) system endows a Business Intelligence system with the intelligence needed to react timely to exogenous as well as endogenous events. To this end, a SaR system needs to kno...

Communication in systems with a high number of processors strongly relies on the interconnection network used, and on its capability of realizing all possible permutations. Scalability and self routing capability are two key factors for the communication structure, and Multistage Interconnection Networks (MINs) have both these features. In this paper, we show how to prove the rearrangeability of two (2 log N – 1)- stage MINs of size N = 16, namely the Shuffle-Shuffle and the Double Butterfly, starting from the approach described in [1] for the Shuffle-Shuffle of size N = 8. Our method generalizes the properties so that they hold for networks of size N = 16, and opens the way to a further possible generalization for other topologies. Furthermore, we propose a backtracking algorithm for distributing the inputs over the switches of the central stage of the network, that can be applied to any network topology if properties to choose pairs of inputs arriving to switches of the central stage are suitably designed.

We present a solver for a class of sparse linear systems that we call quasi block diagonal. The solver combines multi-processors and multi-threaded parallelisms using MPI and OpenMP to implement preconditioned Jacobi. Specific formats for sparse matrices are exploited in order to reduce memory storage requirements. Our experiments show that communication costs are negligible, so as that speed-up and efficiency with respect to the sequential implementation are very high. Our hybrid implementation is tested on a cluster and compared to Intel MKL PARDISO linear solver.

Information exchange has a key role both in distributed systems and in Data Centers. The all-to-all personalized communication (or complete exchange) is a relevant communication pattern in multiprocessor applications, such as matrix transposition, fast Fourier transform and distributed table lookup, and in Data Center applications, such as MapReduce and Spark. All-to-all personalized communication problem has been extensively studied in the past for many networks topologies. Interesting results are on Multistage Interconnection Networks (MINs) with $\log N$ stages $(N$ is the size of the network), and are based on the realization of a sequence of permutations forming a Latin square, i.e. a matrix whose elements occur once in each row and each column. If a particular Latin square is desired, MINs with $\log N$ stage are not adequate, since they cannot realize all possible permutations. On the contrary, the use of double MINs, having $2\log N-1$ stages, can allow in principle the realization of any Latin square, the use of which could make possible particular applications.In this work, we consider the Butterfly-Butterfly network to realize the Latin square consisting of the identity permutation and its N-1 rotations, and we show how to obtain the sequence of rotations forming such a Latin square, without storing it. We propose a method to realize the N permutations in pipeline fashion in $O(N)$ time, that is optimal. Our method can also be applied in systems that use a single Butterfly simply passing through the network twice, and in Data Centers using the flattened butterfly as network.

System level verification of cyber-physical systems has the goal of verifying that the whole (i.e., software + hardware) system meets the given specifications. Model checkers for hybrid systems cannot handle system level verification of actual systems. Thus, Hardware In the Loop Simulation (HILS) is currently the main workhorse for system level verification. By using model checking driven exhaustive HILS, System Level Formal Verification (SLFV) can be effectively carried out for actual systems.We present a parallel random exhaustive HILS based model checker for hybrid systems that, by simulating all operational scenarios exactly once in a uniform random order, is able to provide, at any time during the verification process, an upper bound to the probability that the System Under Verification exhibits an error in a yet-to-be-simulated scenario (Omission Probability).We show effectiveness of the proposed approach by presenting experimental results on SLFV of the Inverted Pendulum on a Cart and the Fuel Control System examples in the Simulink distribution. To the best of our knowledge, no previously published model checker can exhaustively verify hybrid systems of such a size and provide at any time an upper bound to the Omission Probability.

Background Gene fusions derive from chromosomal rearrangements. The resulting chimeric transcripts are often endowed with oncogenic potential. Furthermore, they serve as diagnostic tools for the clinical classification of cancer subgroups with different prognosis and, in some cases, they can provide specific drug targets. To date, many efforts have been carried out to study gene fusion events occurring in tumor samples. In recent years, the availability of a comprehensive next-generation sequencing dataset for all existing human tumor cell lines has provided the opportunity to further investigate these data in order to identify novel and still uncharacterized gene fusion events. Results In our work, we have extensively reanalyzed 935 paired-end RNA-sequencing experiments downloaded from the Cancer Cell Line Encyclopedia repository, aiming at addressing novel putative cell-line specific gene fusion events in human malignancies. The bioinformatics analysis has been performed by the execution of four gene fusion detection algorithms. The results have been further prioritized by running a Bayesian classifier that makes an in silico validation. The collection of fusion events supported by all of the predictive software results in a robust set of ∼1,700 in silico predicted novel candidates suitable for downstream analyses. Given the huge amount of data and information produced, computational results have been systematized in a database named LiGeA. The database can be browsed through a dynamic and interactive web portal, further integrated with validated data from other well-known repositories. Taking advantage of the intuitive query forms, the users can easily access, navigate, filter, and select the putative gene fusions for further validations and studies. They can also find suitable experimental models for a given fusion of interest. Conclusions We believe that the LiGeA resource can represent not only the first compendium of both known and putative novel gene fusion events in the catalog of all of the human malignant cell lines but it can also become a handy starting point for wet-lab biologists who wish to investigate novel cancer biomarkers and specific drug targets.

Cyber Physical Systems (CPSs) consist of hardware and software components. To verify that the whole (i.e., software + hardware) system meets the given specifications, exhaustive simulation-based approaches (Hardware In the Loop Simulation, HILS) can be effectively used by first generating all relevant simulation scenarios (i.e., sequences of disturbances) and then actually simulating all of them (verification phase). When considering the whole verification activity, we see that the above mentioned verification phase is repeated until no error is found. Accordingly, in order to minimise the time taken by the whole verification activity, in each verification phase we should, ideally, start by simulating scenarios witnessing errors (counterexamples). Of course, to know beforehand the set of such scenarios is not feasible. In this paper we show how to select scenarios so as to minimise the Worst Case Expected Verification Time. Simulation: main workhorse for System Level Verification of Cyber Physical Systems.A counterexample is a simulation scenario witnessing a design error.WCEVT: max expected number of scenarios simulated before hitting a counterexample.We show that the minimum WCEVT is (n+1)/2 (n number of simulation scenarios).The infinite set of optimal simulation strategies forms a convex bounded polytope.

In this work we propose a high performance parallelization of the software package COMPSYN, devoted to the production of syntethic seismograms, on a cluster of multicore processors with multiple GPUs. To design and implement the proposed high performance version, we started from a naive parallel version of COMPSYN. The naive version consists in a simple parallelization on both device side, obtained by exploiting CUDA, and host side, obtained by exploiting the MPI paradigm and OpenMP API. The proposed high performance version implements several practical techniques of CUDA programming and deeply exploits the GPU architecture, thus achieving a much better performance with respect to the naive version. We compare the performance of the proposed high performance version and that of the naive one with the performance of the version running on the cluster of multicore processors without invoking the GPUs. We obtain for the high performance GPU version a speedup of 25x over the version running on the cluster of multicore processors without GPUs against the 10x of the naive version. Regarding the sequential version, we estimate about 380x the speedup of the high performance GPU version against the about 140x of the naive version.

The use of wireless mobile sensors is of great relevance for a number of strategic applications devoted to monitoring critical areas where sensors can not be deployed manually. Mobile sensors can adapt their position on the basis of a local evaluation of coverage, thus permitting an autonomous deployment. Several algorithms have been proposed to deploy mobile sensors over an area of interest. The applicability of these approaches largely depends on a proper formalization of rigorous rules to coordinate sensor movements, solve local conflicts and manage possible failures of communications and devices. In this paper we introduce P&P, a communication protocol that permits a correct and efficient coordination of sensor movements in agreement with the Push & Pull algorithm. We deeply investigate and solve the problems that may occur when coordinating asynchronous local decisions in the presence of an unreliable transmission medium and possibly faulty devices such as in the typical working scenario of mobile sensor networks. Simulation results show the performance of our protocol under a range of operative settings, including conflict situations and irregularly shaped target areas. Furthermore, a performance comparison between the P&P protocol and one of the best solutions based on the virtual force approach, shows the superiority of our proposal in terms of deployment time, message exchanges and energy consumption.

In this paper we study the topological equivalence problem of multistage interconnection networks (MINs). We prove a new characterization of topologically equivalent MINs by means of a novel approach. Applying this characterization to log N stage MINs we completely describe the equivalence class which the Reverse Baseline belongs to. Most important, we apply the characterization to (2 log N - 1) stage MINs obtained as concatenation of two log N stage Reverse Baseline equivalent MINs: in this way, we deduce an O(N log N) time algorithm testing the equivalence of two such MINs. This result substantially improves the time complexity of the previously known algorithms (O(N4 log N)). Finally, we determine the number of different equivalence classes of (2 log N - 1) stage MINs and we characterize each of them.

The edge-bandwidth problem is an analog of the classical bandwidth problem, in which one has to label the edges of a graph by distinct integers such that the maximum difference of labels of any two incident edges is minimized. We prove tight bounds on the edge-bandwidth of hypercube and butterfly graphs, and complete k-ary trees which extends and improves on previous known results.

Many simulation based Bounded Model Checking approaches to System Level Formal Verification (SLFV) have been devised. Typically such approaches exploit the capability of simulators to save computation time by saving and restoring the state of the system under simulation. However, even though such approaches aim to (bounded) formal verification, as a matter of fact, the simulator behaviour is not formally modelled and the proof of correctness of the proposed approaches basically relies on the intuitive notion of simulator behaviour. This gap makes it hard to check if the optimisations introduced to speed up the simulation do not actually omit checking relevant behaviours of the system under verification. The aim of this paper is to fill the above gap by presenting a formal semantics for simulators., Comment: In Proceedings GandALF 2015, arXiv:1509.06858

The goal of System Level Formal Verification is to show system correctness notwithstanding uncontrollable events (disturbances), as for example faults, variation in system parameters, external inputs, etc. This may be achieved with an exhaustive Hardware In the Loop Simulation based approach, by considering all relevant scenarios in the System Under Verification (SUV) operational environment. In this paper, we present SyLVaaS, a Web-based tool enabling Verification as a Service (VaaS). SyLVaaS implements an assume-guarantee approach to the verification problem outlined above. SyLVaaS takes as input a high-level model defining the SUV operational environment and computes, using parallel algorithms deployed in a cluster infrastructure, a set of highly optimised simulation campaigns, which can be executed in an embarrassingly parallel fashion on a set of Simulink instances, using a platform independent Simulink driver downloadable from the SyLVaaS Web site. As the actual simulation is carried out at the user premises (e.g., in a private cluster), SyLVaaS allows full Intellectual Property protection on the SUV model and the user verification flow. The simulation campaigns computed by SyLVaaS randomise the verification order of operational scenarios and this enables, at anytime during the parallel simulation activity, the estimation of the completion time and the computation of an upper bound to the Omission Probability, i.e., the probability that there is a yet-to-be-simulated operational scenario which violates the property under verification. This information supports graceful degradation in the verification activity. We show effectiveness of the SyLVaaS algorithms and infrastructure by evaluating the system on industry-scale input related to the verification of the Fuel Control System (FCS) model in the Simulink distribution.

Verification of digital circuits by Cycle-based simulation can be performed in parallel. The parallel implementation requires two phases: the compilation phase, that sets up the data needed for the execution of the simulation, and the simulation phase, that consists in executing the parallel simulation of the considered circuit for a certain number of cycles. During the early phase of design, compilation phase has to be repeated each time a bug is found. Thus, if the time of the compilation phase is too high, the advantages stemming from the parallel approach may be lost. In this work we propose an effective version of the compilation phase and compute the corresponding execution time. We also analyze the percentage of execution time required by the different steps of the compilation phase for a set of literature benchmarks. Further, we implemented the simulation phase exploiting the GPU architecture, and we computed the execution times for a set of benchmarks obtaining values comparable with literature ones. Finally, we implemented the sequential version of the Cycle-based simulation in such a way that the execution time is optimized. We used the sequential values to compute the speedup of the parallel version for the considered set of benchmarks.

In this paper we deal with the layout of interconnection networks on three-dimensional grids. In particular, in the first part we prove a general formula for calculating an exact value for the lower bound on the volume. Then we introduce the new notion of k-3D double channel routing and we use it to exhibit an optimal three-dimensional layout for butterfly networks. Finally, we show a method to lay out multigrid and X-tree networks in optimal volume.

In this paper, we study the problem of laying out a multigrid network, M N , on a grid of minimum area. Precisely, we describe a layout having area ( 5 2 N−3)×(3N−4) , which is of the same order of magnitude as the lower bound.

The goal of System Level Formal Verification (SLFV) is to show system correctness notwithstanding uncontrollable events (such as: faults, variation in system parameters, external inputs, etc). Hardware In the Loop Simulation (HILS) based SLFV attains such a goal by considering exhaustively all relevant simulation scenarios. We present a distributed multi-core algorithm for HILS-based SLFV. Our experimental results on the Fuel Control System example in the Simulink distribution show that by using 64 machines with an 8 core processor each we can complete the SLFV activity in about 27 hours whereas a sequential approach would require more than 200 days. To the best of our knowledge this is the first time that a distributed multi-core algorithm for HILS-based SLFV is presented.

We present a parallel random exhaustive Hardware In the Loop Simulation based model checker for hybrid systems that, by simulating all operational scenarios exactly once in a uniform random order, is able to provide, at any time during the verification process, an upper bound to the probability that the System Under Verification exhibits an error in a yet-to-be-simulated scenario (Omission Probability). We show effectiveness of the proposed approach by presenting experimental results on System Level Formal Verification of the Fuel Control System example in the Simulink distribution. To the best of our knowledge, no previously published model checker can exhaustively verify hybrid systems of such a size and provide at any time an upper bound to the Omission Probability.

We show how by combining Explicit Model Checking techniques and simulation it is possible to effectively carry out (bounded) System Level Formal Verification of large Hybrid Systems such as those defined using model-based tools like Simulink. We use an explicit model checker (namely, CMurphi) to generate all possible (finite horizon) simulation scenarios and then optimise the simulation of such scenarios by exploiting the ability of simulators to save and restore visited states. We show feasibility of our approach by presenting experimental results on the verification of the fuel control system example in the Simulink distribution. To the best of our knowledge this is the first time that (exhaustive) verification has been carried out for hybrid systems of such a size.

A self-routing multi-logN permutation network is presented and studied. This network has 3log/sub 2/ N-2 depth and N(log/sub 2//sup /spl gamma//N)(3log/sub 2/, N-2)/2 nodes, where N is the number of network inputs and /spl gamma/ a constant very close to 1. A parallel routing algorithm runs in 3log/sub 2/N-2 time on this network. The overall system (network and algorithm) can work in pipeline and it is asymptotically nonblocking in the sense that its blocking probability vanishes when N increases, hence the quasi-totality of the information synchronously arrives in 3log/sub 2/N-2 steps at the network outputs. This network presents very good fault tolerance, a modular architecture, and it is suitable for information exchange in very large scale parallel processors and communication systems. >

In this work we propose two different parallel versions of the software package COMPSYN, devoted to the production of syntethic seismograms. The first version consists in the parallelization of the code to run on a cluster of multicore processors and is obtained by exploiting the MPI paradigm and OpenMP API to the end of maximizing the performance on multicore processors. The second version exploits the set of GPU associated to the multicore processor cluster and uses CUDA to take advantage of the GPU's computational power. We analyze the application performance of the two different implementations by using a real case study. In particular, we obtain for the GPU version a speedup of 10x over the parallelized version running on the cluster of multicore processors. Furthermore, we can estimate about at least 100x the speedup of the GPU version using a single node of the cluster with respect to the original sequential version.

The use of mobile sensors is of great relevance to monitor critical areas where sensors cannot be deployed manually. The presence of data collector sinks causes increased energy depletion in their proximity, due to the higher relay load under multi-hop communication schemes (sink-hole phenomenon). We propose a new approach towards the solution of this problem by means of an autonomous deployment algorithm that guarantees the adaptation of the sensor density to the sink proximity and enables their selective activation. The proposed algorithm also permits a fault tolerant and self-healing deployment, and allows the realization of an integrated solution for deployment, dynamic relocation and selective sensor activation. We formally prove the termination of our algorithm. Performance comparisons between our proposal and previous approaches show how the former can efficiently reach a deployment at the desired variable density with moderate energy consumption under a wide range of operative settings.

Mobile sensor networks are important for several strategic applications devoted to monitoring critical areas. In such hostile scenarios, sensors cannot be deployed manually and are either sent from a safe location or dropped from an aircraft. Mobile devices permit a dynamic deployment reconfiguration that improves the coverage in terms of completeness and uniformity. In this paper we propose a distributed algorithm for the autonomous deployment of mobile sensors called Push&Pull. According to our proposal, movement decisions are made by each sensor on the basis of locally available information and do not require any prior knowledge of the operating conditions or any manual tuning of key parameters. We formally prove that, when a sufficient number of sensors are available, our approach guarantees a complete and uniform coverage. Furthermore, we demonstrate that the algorithm execution always terminates preventing movement oscillations. Numerous simulations show that our algorithm reaches a complete coverage within reasonable time with moderate energy consumption, even when the target area has irregular shapes. Performance comparisons between Push&Pull and one of the most acknowledged algorithms show how the former one can efficiently reach a more uniform and complete coverage under a wide range of working scenarios., Technical Report. This paper has been published on Wireless Networks, Springer. Animations and the complete code of the proposed algorithm are available for download at the address: http://www.dsi.uniroma1.it/~novella/mobile_sensors/

In this paper we address the problem of deploying heterogeneous mobile sensors over a target area. We show how traditional approaches designed for homogeneous networks fail when adopted in the heterogeneous operative setting.

The antibandwidth problem is to label vertices of a n-vertex graph injectively by 1 , 2 , 3 , … n , such that the minimum difference of labels of adjacent vertices is maximised. The problem is motivated by obnoxious facility location problem, radiocolouring, work and game scheduling and is dual to the well known bandwidth problem. We prove exact results for the antibandwidth of complete k-ary trees, k even, and estimate the parameter for odd k up to the second order term. This extends previous results for complete binary trees.

The use of mobile sensors is of great relevance for a number of strategic applications devoted to monitoring critical areas where sensors can not be deployed manually. In these networks, each sensor adapts its position on the basis of a local evaluation of the coverage efficiency, thus permitting an autonomous deployment. Several algorithms have been proposed to deploy mobile sensors over the area of interest. The applicability of these approaches largely depends on a proper formalization of rigorous rules to coordinate sensor movements, solve local conflicts and manage possible failures of communications and devices. In this paper we introduce P&P, a communication protocol that permits a correct and efficient coordination of sensor movements in agreement with the PUSH&PULL algorithm. We deeply investigate and solve the problems that may occur when coordinating asynchronous local decisions in the presence of an unreliable transmission medium and possibly faulty devices such as in the typical working scenario of mobile sensor networks. Simulation results show the performance of our protocol under a range of operative settings, including conflict situations, irregularly shaped target areas, and node failures., Technical report

The use of mobile sensors is motivated by the necessity to monitor critical areas where sensor deployment cannot be performed manually. In these working scenarios, sensors must adapt their initial position to reach a final deployment which meets some given performance objectives such as coverage extension and uniformity, total moving distance, number of message exchanges and convergence rate. We propose an original algorithm for autonomous deployment of mobile sensors called Snap & Spread . Decisions regarding the behavior of each sensor are based on locally available information and do not require any prior knowledge of the operating conditions nor any manual tuning of key parameters. We conduct extensive simulations to evaluate the performance of our algorithm. This experimental study shows that, unlike previous solutions, our algorithm reaches a final stable deployment, uniformly covering even irregular target areas. Simulations also give insights on the choice of some algorithm variants that may be used under some different operative settings.

In this paper we propose an algorithm for the autonomous deployment of mobile sensors over critical target areas where sensors cannot be deployed manually. The application of our approach does not require prior knowledge of the working scenario nor any manual tuning of key parameters. Our algorithm is completely distributed and sensors make movement decisions on the basis of locally available information. We prove that our approach guarantees a complete coverage, provided that a sufficient number of sensors are available. Furthermore, we demonstrate that the algorithm execution always terminates preventing movement oscillations. We compare our proposal with one of the most acknowledged algorithms by means of extensive simulations, showing that our algorithm reaches a complete and more uniform coverage under a wide range of operating conditions.

In this paper we consider the three-dimensional layout of hypercube networks. Namely, we study the problem of laying hypercube networks out on the three-dimensional grid with the properties that all nodes are represented as rectangular slices and lie on two opposite sides of the bounding box of the layout volume. We present both a lower bound and a layout method providing an upper bound on the layout volume of the hypercube network.

In this paper we deal with the layout of interconnection networks on three-dimensional grids. In particular, in the first part we prove a general formula for calculating an exact value for the lower bound on the volume. Then we introduce the new notion of κ-3D double channel routing and we use it to exhibit an optimal three-dimensional layout for butterfly networks. Finally, we show a method to lay out multigrid and X-tree networks in optimal volume.

A parallel arithmetic, suitable for optical computers, can be obtained using two main approaches 1) residue number system1,2 and 2) redundant number representations3,4. In fact using of both approaches it is possible to build totally parallel adders operating by symbolic substitution (SS)2,5–7 and in constant time (the adding time is independent of the length of the operand digit strings, N). Using a residue number system, the size of the SS Truth Tables required for the carry-free addition heavily increases with numerical range involved1,2, and these tables depend on the digit position. On the contrary, additions of redundant numbers can be performed in constant time by small SS Truth Tables which are independent of the digit positions.

A family of redundant binary number representations, obtained by generalization of the RB (redundant binary) number representation, is introduced. All these number representations are suitable for optical computing and have properties similar to the RB representation. In particular, the p -RB (packed redundant binary) number representation introduced in this work has efficiency greater than both RB and MSD (modified signed digit) representations. With p -RB numbers the algebraic sum is always permitted in constant time for any efficiency value. p -RB representations also fit in a natural way the 2's complement binary number system. Symbolic substitution truth tables for the algebraic sum and several examples of computation are also given.

A self-routing multi-log-N permutation network is presented and studied. This network has log/sub 2/N depth and N(log/sub 2//sup 2/N+log/sub 2/N)/2 nodes, where N is the number of network inputs. Its parallel routing algorithm runs in log/sub 2/N time. The network architecture guarantees that only a negligible quantity of information is blocked, while the quasi-totality of the information synchronously reaches the network outputs in log/sub 2/N steps. This network works in pipeline, it has a modular architecture suitable for very large N, it can be used as very high performance fast packet switching fabric, and it is suitable for information exchange in very-large-scale multiprocessor systems. >

A simple redundant binary number representation suitable for digital-optical computers is presented. By means of this representation it is possible to build an arithmetic with carry-free parallel algebraic sums carried out in constant time and parallel multiplication in log N time. This redundant number representation naturally fits the 2's complement binary number system and permits the construction of inherently parallel arithmetic units that are used in various optical technologies. Some properties of this number representation and several examples of computation are presented.

In parallel/distributed computing systems, the all-to-all personalized communication (or complete exchange) is required in numerous applications of parallel processing. In this paper, we consider this problem for logN stage Multistage Interconnection Networks (MINs). It is proved that the set of admissible permutations for a MIN can be partitioned in Latin Squares. Since routing permutations belonging to a Latin Square provides the all-to-all personalized communication, a method to realize the complete exchange with time complexity O(N), that is optimal, can be derived. This method, compared with other ones in literature, does not necessitate of neither pre-computation nor memory allocation to record the Latin Square, because an explicit construction of it is not required; furthermore it is applicable to any logN stage multistage networks since it is independent of the topology.

In Silico Clinical Trials (ISCT), i.e., clinical experimental campaigns carried out by means of computer simulations, hold the promise to decrease time and cost for the safety and efficacy assessment of pharmacological treatments, reduce the need for animal and human testing, and enable precision medicine.In this paper we present a case study aiming at quantifying, by means of a multi-arm ISCT supervised by intelligent search, the potential impact of precision medicine approaches on a real pharmacological treatment, namely the downregulation phase of a complex clinical protocol for assisted reproduction.