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Author Intrigila, Benedetto; Magazzeni, Daniele; Melatti, Igor; Tronci, Enrico
Title A Model Checking Technique for the Verification of Fuzzy Control Systems Type Conference Article
Year 2005 Publication CIMCA '05: Proceedings of the International Conference on Computational Intelligence for Modelling, Control and Automation and International Conference on Intelligent Agents, Web Technologies and Internet Commerce Vol-1 (CIMCA-IAWTIC'06) Abbreviated Journal
Volume Issue Pages 536-542
Keywords
Abstract Fuzzy control is well known as a powerful technique for designing and realizing control systems. However, statistical evidence for their correct behavior may be not enough, even when it is based on a large number of samplings. In order to provide a more systematic verification process, the cell-to-cell mapping technology has been used in a number of cases as a verification tool for fuzzy control systems and, more recently, to assess their optimality and robustness. However, cell-to-cell mapping is typically limited in the number of cells it can explore. To overcome this limitation, in this paper we show how model checking techniques may be instead used to verify the correct behavior of a fuzzy control system. To this end, we use a modified version of theMurphi verifier, which ease the modeling phase by allowing to use finite precision real numbers and external C functions. In this way, also already designed simulators may be used for the verification phase. With respect to the cell mapping technique, our approach appears to be complementary; indeed, it explores a much larger number of states, at the cost of being less informative on the global dynamic of the system.
Address
Corporate Author Thesis
Publisher IEEE Computer Society Place of Publication Washington, DC, USA Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN 0-7695-2504-0-01 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Immt05 Serial 75
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Author Brizzolari, Francesco; Melatti, Igor; Tronci, Enrico; Della Penna, Giuseppe
Title Disk Based Software Verification via Bounded Model Checking Type Conference Article
Year 2007 Publication APSEC '07: Proceedings of the 14th Asia-Pacific Software Engineering Conference Abbreviated Journal
Volume Issue Pages 358-365
Keywords
Abstract One of the most successful approach to automatic software verification is SAT based bounded model checking (BMC). One of the main factors limiting the size of programs that can be automatically verified via BMC is the huge number of clauses that the backend SAT solver has to process. In fact, because of this, the SAT solver may easily run out of RAM. We present two disk based algorithms that can considerably decrease the number of clauses that a BMC backend SAT solver has to process in RAM. Our experimental results show that using our disk based algorithms we can automatically verify programs that are out of reach for RAM based BMC.
Address
Corporate Author Thesis
Publisher IEEE Computer Society Place of Publication Washington, DC, USA Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN 0-7695-3057-5 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Bmtd07 Serial 76
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Author Della Penna, Giuseppe; Di Marco, Antinisca; Intrigila, Benedetto; Melatti, Igor; Pierantonio, Alfonso
Title Interoperability mapping from XML schemas to ER diagrams Type Journal Article
Year 2006 Publication Data Knowl. Eng. Abbreviated Journal
Volume 59 Issue 1 Pages 166-188
Keywords
Abstract The eXtensible Markup Language (XML) is a de facto standard on the Internet and is now being used to exchange a variety of data structures. This leads to the problem of efficiently storing, querying and retrieving a great amount of data contained in XML documents. Unfortunately, XML data often need to coexist with historical data. At present, the best solution for storing XML into pre-existing data structures is to extract the information from the XML documents and adapt it to the data structures’ logical model (e.g., the relational model of a DBMS). In this paper, we introduce a technique called Xere (XML entity–relationship exchange) to assist the integration of XML data with other data sources. To this aim, we present an algorithm that maps XML schemas into entity–relationship diagrams, discuss its soundness and completeness and show its implementation in XSLT.
Address
Corporate Author Thesis
Publisher Elsevier Science Publishers B. V. Place of Publication Amsterdam, The Netherlands, The Netherlands Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN 0169-023x ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Ddimp06 Serial 77
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Author Della Penna, Giuseppe; Intrigila, Benedetto; Melatti, Igor; Tronci, Enrico; Venturini Zilli, Marisa
Title Finite horizon analysis of Markov Chains with the Mur$\varphi$ verifier Type Journal Article
Year 2006 Publication Int. J. Softw. Tools Technol. Transf. Abbreviated Journal
Volume 8 Issue 4 Pages 397-409
Keywords
Abstract In this paper we present an explicit disk-based verification algorithm for Probabilistic Systems defining discrete time/finite state Markov Chains. Given a Markov Chain and an integer k (horizon), our algorithm checks whether the probability of reaching an error state in at most k steps is below a given threshold. We present an implementation of our algorithm within a suitable extension of the Mur$\varphi$ verifier. We call the resulting probabilistic model checker FHP-Mur$\varphi$ (Finite Horizon Probabilistic Mur$\varphi$). We present experimental results comparing FHP-Mur$\varphi$ with (a finite horizon subset of) PRISM, a state-of-the-art symbolic model checker for Markov Chains. Our experimental results show that FHP-Mur$\varphi$ can handle systems that are out of reach for PRISM, namely those involving arithmetic operations on the state variables (e.g. hybrid systems).
Address
Corporate Author Thesis
Publisher Springer-Verlag Place of Publication Berlin, Heidelberg Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN 1433-2779 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Dimtz06 Serial 78
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Author Della Penna, Giuseppe; Magazzeni, Daniele; Tofani, Alberto; Intrigila, Benedetto; Melatti, Igor; Tronci, Enrico
Title Automated Generation of Optimal Controllers through Model Checking Techniques Type Conference Article
Year 2006 Publication Icinco-Icso Abbreviated Journal
Volume Issue Pages 26-33
Keywords
Abstract We present a methodology for the synthesis of controllers, which exploits (explicit) model checking techniques. That is, we can cope with the systematic exploration of a very large state space. This methodology can be applied to systems where other approaches fail. In particular, we can consider systems with an highly non-linear dynamics and lacking a uniform mathematical description (model). We can also consider situations where the required control action cannot be specified as a local action, and rather a kind of planning is required. Our methodology individuates first a raw optimal controller, then extends it to obtain a more robust one. A case study is presented which considers the well known truck-trailer obstacle avoidance parking problem, in a parking lot with obstacles on it. The complex non-linear dynamics of the truck-trailer system, within the presence of obstacles, makes the parking problem extremely hard. We show how, by our methodology, we can obtain optimal controllers with different degrees of robustness.
Address
Corporate Author Thesis
Publisher INSTICC Press Place of Publication Editor Andrade-Cetto, J.; Ferrier, J.-L.; Pereira, J. M. C. D.; Filipe, J.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN 972-8865-59-7 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Dimmtt06 Serial 79
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Author Melatti, Igor; Palmer, Robert; Sawaya, Geoffrey; Yang, Yu; Kirby, Robert Mike; Gopalakrishnan, Ganesh
Title Parallel and distributed model checking in Eddy Type Journal Article
Year 2009 Publication Int. J. Softw. Tools Technol. Transf. Abbreviated Journal
Volume 11 Issue 1 Pages 13-25
Keywords
Abstract Model checking of safety properties can be scaled up by pooling the CPU and memory resources of multiple computers. As compute clusters containing 100s of nodes, with each node realized using multi-core (e.g., 2) CPUs will be widespread, a model checker based on the parallel (shared memory) and distributed (message passing) paradigms will more efficiently use the hardware resources. Such a model checker can be designed by having each node employ two shared memory threads that run on the (typically) two CPUs of a node, with one thread responsible for state generation, and the other for efficient communication, including (1) performing overlapped asynchronous message passing, and (2) aggregating the states to be sent into larger chunks in order to improve communication network utilization. We present the design details of such a novel model checking architecture called Eddy. We describe the design rationale, details of how the threads interact and yield control, exchange messages, as well as detect termination. We have realized an instance of this architecture for the Murphi modeling language. Called Eddy_Murphi, we report its performance over the number of nodes as well as communication parameters such as those controlling state aggregation. Nearly linear reduction of compute time with increasing number of nodes is observed. Our thread task partition is done in such a way that it is modular, easy to port across different modeling languages, and easy to tune across a variety of platforms.
Address
Corporate Author Thesis
Publisher Springer-Verlag Place of Publication Berlin, Heidelberg Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN 1433-2779 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Mpsykg09 Serial 80
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Author Intrigila, Benedetto; Melatti, Igor; Tofani, Alberto; Macchiarelli, Guido
Title Computational models of myocardial endomysial collagen arrangement Type Journal Article
Year 2007 Publication Computer Methods and Programs in Biomedicine Abbreviated Journal
Volume 86 Issue 3 Pages 232-244
Keywords
Abstract Collagen extracellular matrix is one of the factors related to high passive stiffness of cardiac muscle. However, the architecture and the mechanical aspects of the cardiac collagen matrix are not completely known. In particular, endomysial collagen contribution to the passive mechanics of cardiac muscle as well as its micro anatomical arrangement is still a matter of debate. In order to investigate mechanical and structural properties of endomysial collagen, we consider two alternative computational models of some specific aspects of the cardiac muscle. These two models represent two different views of endomysial collagen distribution: (1) the traditional view and (2) a new view suggested by the data obtained from scanning electron microscopy (SEM) in NaOH macerated samples (a method for isolating collagen from the other tissue). We model the myocardial tissue as a net of spring elements representing the cardiomyocytes together with the endomysial collagen distribution. Each element is a viscous elastic spring, characterized by an elastic and a viscous constant. We connect these springs to imitate the interconnections between collagen fibers. Then we apply to the net of springs some external forces of suitable magnitude and direction, obtaining an extension of the net itself. In our setting, the ratio forces magnitude /net extension is intended to model the stress /strain ratio of a microscopical portion of the myocardial tissue. To solve the problem of the correct identification of the values of the different parameters involved, we use an artificial neural network approach. In particular, we use this technique to learn, given a distribution of external forces, the elastic constants of the springs needed to obtain a desired extension as an equilibrium position. Our experimental findings show that, in the model of collagen distribution structured according to the new view, a given stress /strain ratio (of the net of springs, in the sense specified above) is obtained with much smaller (w.r.t. the other model, corresponding to the traditional view) elasticity constants of the springs. This seems to indicate that by an appropriate structure, a given stiffness of the myocardial tissue can be obtained with endomysial collagen fibers of much smaller size.
Address
Corporate Author Thesis
Publisher Elsevier North-Holland, Inc. Place of Publication New York, NY, USA Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN 0169-2607 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Imtm07 Serial 82
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Author Della Penna, Giuseppe; Magazzeni, Daniele; Tofani, Alberto; Intrigila, Benedetto; Melatti, Igor; Tronci, Enrico
Title Automatic Synthesis of Robust Numerical Controllers Type Conference Article
Year 2007 Publication Icas '07 Abbreviated Journal
Volume Issue Pages 4
Keywords
Abstract A major problem of numerical controllers is their robustness, i.e. the state read from the plant may not be in the controller table, although it may be close to some states in the table. For continuous systems, this problem is typically handled by interpolation techniques. Unfortunately, when the plant contains both continuous and discrete variables, the interpolation approach does not work well. To cope with this kind of systems, we propose a general methodology that exploits explicit model checking in an innovative way to automatically synthesize a (time-) optimal numerical controller from a plant specification and apply an optimized strengthening algorithm only on the most significant states, in order to reach an acceptable robustness degree. We implemented all the algorithms within our CGMurphi tool, an extension of the well-known CMurphi verifier, and tested the effectiveness of our approach by applying it to the well-known truck and trailer obstacles avoidance problem.
Address
Corporate Author Thesis
Publisher IEEE Computer Society Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN 0-7695-2859-5 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Dmtimt07 Serial 89
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Author Della Penna, Giuseppe; Intrigila, Benedetto; Melatti, Igor; Tronci, Enrico; Venturini Zilli, Marisa
Title Exploiting Transition Locality in Automatic Verification of Finite State Concurrent Systems Type Journal Article
Year 2004 Publication Sttt Abbreviated Journal
Volume 6 Issue 4 Pages 320-341
Keywords
Abstract In this paper we show that statistical properties of the transition graph of a system to be verified can be exploited to improve memory or time performances of verification algorithms. We show experimentally that protocols exhibit transition locality. That is, with respect to levels of a breadth-first state space exploration, state transitions tend to be between states belonging to close levels of the transition graph. We support our claim by measuring transition locality for the set of protocols included in the Mur$\varphi$ verifier distribution. We present a cache-based verification algorithm that exploits transition locality to decrease memory usage and a disk-based verification algorithm that exploits transition locality to decrease disk read accesses, thus reducing the time overhead due to disk usage. Both algorithms have been implemented within the Mur$\varphi$ verifier. Our experimental results show that our cache-based algorithm can typically save more than 40% of memory with an average time penalty of about 50% when using (Mur$\varphi$) bit compression and 100% when using bit compression and hash compaction, whereas our disk-based verification algorithm is typically more than ten times faster than a previously proposed disk-based verification algorithm and, even when using 10% of the memory needed to complete verification, it is only between 40 and 530% (300% on average) slower than (RAM) Mur$\varphi$ with enough memory to complete the verification task at hand. Using just 300 MB of memory our disk-based Mur$\varphi$ was able to complete verification of a protocol with about $10^9$ reachable states. This would require more than 5 GB of memory using standard Mur$\varphi$.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ DIMTZ04j Serial 91
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Author Mari, Federico; Melatti, Igor; Salvo, Ivano; Tronci, Enrico; Alvisi, Lorenzo; Clement, Allen; Li, Harry
Title Model Checking Nash Equilibria in MAD Distributed Systems Type Conference Article
Year 2008 Publication FMCAD '08: Proceedings of the 2008 International Conference on Formal Methods in Computer-Aided Design Abbreviated Journal
Volume Issue Pages 1-8
Keywords Model Checking, MAD Distributed System, Nash Equilibrium
Abstract We present a symbolic model checking algorithm for verification of Nash equilibria in finite state mechanisms modeling Multiple Administrative Domains (MAD) distributed systems. Given a finite state mechanism, a proposed protocol for each agent and an indifference threshold for rewards, our model checker returns PASS if the proposed protocol is a Nash equilibrium (up to the given indifference threshold) for the given mechanism, FAIL otherwise. We implemented our model checking algorithm inside the NuSMV model checker and present experimental results showing its effectiveness for moderate size mechanisms. For example, we can handle mechanisms which corresponding normal form games would have more than $10^20$ entries. To the best of our knowledge, no model checking algorithm for verification of mechanism Nash equilibria has been previously published.
Address
Corporate Author Thesis
Publisher IEEE Press Place of Publication Piscataway, NJ, USA Editor Cimatti, A.; Jones, R.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume (up) Series Issue Edition
ISSN 978-1-4244-2735-2 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ MarMelSalTroAlvCle08 Serial 93
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