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Author Chierichetti, Flavio; Lattanzi, Silvio; Mari, Federico; Panconesi, Alessandro
Title On Placing Skips Optimally in Expectation Type Conference Article
Year 2008 Publication Web Search and Web Data Mining (WSDM 2008) Abbreviated Journal
Volume Issue Pages 15-24
Keywords Information Retrieval
Abstract We study the problem of optimal skip placement in an inverted list. Assuming the query distribution to be known in advance, we formally prove that an optimal skip placement can be computed quite efficiently. Our best algorithm runs in time O(n log n), n being the length of the list. The placement is optimal in the sense that it minimizes the expected time to process a query. Our theoretical results are matched by experiments with a real corpus, showing that substantial savings can be obtained with respect to the tra- ditional skip placement strategy, that of placing consecutive skips, each spanning sqrt(n) many locations.
Address
Corporate Author Thesis
Publisher Acm Place of Publication Editor Najork, M.; Broder, A.Z.; Chakrabarti, S.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ ChiLatMar08 Serial 94
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Author Bucciarelli, Antonio; de Lorenzis, Silvia; Piperno, Adolfo; Salvo, Ivano
Title Some Computational Properties of Intersection Types (Extended Abstract) Type Journal Article
Year 1999 Publication Abbreviated Journal
Volume Issue Pages 109-118
Keywords lambda calculusCurry types, intersection types, lambda-definability, lambda-terms, strong normalization
Abstract This paper presents a new method for comparing computation-properties of λ-terms typeable with intersection types with respect to terms typeable with Curry types. In particular, strong normalization and λ-definability are investigated. A translation is introduced from intersection typing derivations to Curry typeable terms; the main feature of the proposed technique is that the translation is preserved by β-reduction. This allows to simulate a computation starting from a term typeable in the intersection discipline by means of a computation starting from a simply typeable term. Our approach naturally leads to prove strong normalization in the intersection system by means of purely syntactical techniques. In addition, the presented method enables us to give a proof of a conjecture proposed by Leivant in 1990, namely that all functions uniformly definable using intersection types are already definable using Curry types.
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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 Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ bucciarelli-delorenzis-piperno-salvo:99 Serial 71
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Author Tronci, Enrico
Title Equational Programming in lambda-calculus Type Conference Article
Year 1991 Publication Sixth Annual IEEE Symposium on Logic in Computer Science (LICS) Abbreviated Journal
Volume Issue Pages 191-202
Keywords
Abstract
Address
Corporate Author Thesis
Publisher IEEE Computer Society Place of Publication Amsterdam, The Netherlands Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ lics91 Serial 58
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Author Tronci, Enrico
Title Automatic Synthesis of Controllers from Formal Specifications Type Conference Article
Year 1998 Publication Proc of 2nd IEEE International Conference on Formal Engineering Methods (ICFEM) Abbreviated Journal
Volume Issue Pages 134-143
Keywords
Abstract Many safety critical reactive systems are indeed embedded control systems. Usually a control system can be partitioned into two main subsystems: a controller and a plant. Roughly speaking: the controller observes the state of the plant and sends commands (stimulus) to the plant to achieve predefined goals. We show that when the plant can be modeled as a deterministic finite state system (FSS) it is possible to effectively use formal methods to automatically synthesize the program implementing the controller from the plant model and the given formal specifications for the closed loop system (plant+controller). This guarantees that the controller program is correct by construction. To the best of our knowledge there is no previously published effective algorithm to extract executable code for the controller from closed loop formal specifications. We show practical usefulness of our techniques by giving experimental results on their use to synthesize C programs implementing optimal controllers (OCs) for plants with more than 109 states.
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Corporate Author Thesis
Publisher Place of Publication Brisbane, Queensland, Australia Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ icfem98 Serial 52
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Author Cecconi, Michele; Tronci, Enrico
Title Requirements Formalization and Validation for a Telecommunication Equipment Protection Switcher Type Conference Article
Year 2000 Publication Hase Abbreviated Journal
Volume Issue Pages
Keywords
Abstract
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 Series Issue Edition
ISSN 0-7695-0927-4 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ CeTro00 Serial 29
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Author Tronci, Enrico
Title Formally Modeling a Metal Processing Plant and its Closed Loop Specifications Type Conference Article
Year 1999 Publication 4th IEEE International Symposium on High-Assurance Systems Engineering (HASE) Abbreviated Journal
Volume Issue Pages 151
Keywords
Abstract We present a case study on automatic synthesis of control software from formal specifications for an industrial automation control system. Our aim is to compare the effectiveness (i.e. design effort and controller quality) of automatic controller synthesis from closed loop formal specifications with that of manual controller design followed by automatic verification. The system to be controlled (plant) models a metal processing facility near Karlsruhe. We succeeded in automatically generating C code implementing a (correct by construction) embedded controller for such a plant from closed loop formal specifications. Our experimental results show that for industrial automation control systems automatic synthesis is a viable and profitable (especially as far as design effort is concerned) alternative to manual design followed by automatic verification.
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Corporate Author Thesis
Publisher IEEE Computer Society Place of Publication Washington, D.C, USA Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7695-0418-3 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ hase99 Serial 50
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Author Tronci, Enrico
Title Automatic Synthesis of Control Software for an Industrial Automation Control System Type Conference Article
Year 1999 Publication Proc.of: 14th IEEE International Conference on: Automated Software Engineering (ASE) Abbreviated Journal
Volume Issue Pages 247-250
Keywords
Abstract We present a case study on automatic synthesis of control software from formal specifications for an industrial automation control system. Our aim is to compare the effectiveness (i.e. design effort and controller quality) of automatic controller synthesis from closed loop formal specifications with that of manual controller design, followed by automatic verification. Our experimental results show that for industrial automation control systems, automatic synthesis is a viable and profitable (especially as far as design effort is concerned) alternative to manual design, followed by automatic verification.
Address
Corporate Author Thesis
Publisher Place of Publication Cocoa Beach, Florida, USA Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ ase99 Serial 49
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Author Tronci, Enrico; Della Penna, Giuseppe; Intrigila, Benedetto; Venturini Zilli, Marisa
Title A Probabilistic Approach to Automatic Verification of Concurrent Systems Type Conference Article
Year 2001 Publication 8th Asia-Pacific Software Engineering Conference (APSEC) Abbreviated Journal
Volume Issue Pages 317-324
Keywords
Abstract The main barrier to automatic verification of concurrent systems is the huge amount of memory required to complete the verification task (state explosion). In this paper we present a probabilistic algorithm for automatic verification via model checking. Our algorithm trades space with time. In particular, when memory is full because of state explosion our algorithm does not give up verification. Instead it just proceeds at a lower speed and its results will only hold with some arbitrarily small error probability. Our preliminary experimental results show that by using our probabilistic algorithm we can typically save more than 30% of RAM with an average time penalty of about 100% w.r.t. a deterministic state space exploration with enough memory to complete the verification task. This is better than giving up the verification task because of lack of memory.
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Corporate Author Thesis
Publisher IEEE Computer Society Place of Publication Macau, China Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7695-1408-1 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ apsec01 Serial 43
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Author Bucciarelli, Antonio; Piperno, Adolfo; Salvo, Ivano
Title Intersection types and λ-definability Type Journal Article
Year 2003 Publication Mathematical Structures in Computer Science Abbreviated Journal
Volume 13 Issue 1 Pages 15-53
Keywords
Abstract This paper presents a novel method for comparing computational properties of λ-terms that are typeable with intersection types, with respect to terms that are typeable with Curry types. We introduce a translation from intersection typing derivations to Curry typeable terms that is preserved by β-reduction: this allows the simulation of a computation starting from a term typeable in the intersection discipline by means of a computation starting from a simply typeable term. Our approach proves strong normalisation for the intersection system naturally by means of purely syntactical techniques. The paper extends the results presented in Bucciarelli et al. (1999) to the whole intersection type system of Barendregt, Coppo and Dezani, thus providing a complete proof of the conjecture, proposed in Leivant (1990), that all functions uniformly definable using intersection types are already definable using Curry types.
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Corporate Author Thesis
Publisher Cambridge University Press Place of Publication New York, NY, USA Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-1295 ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Bucciarelli-Piperno-Salvo:MSCS-03 Serial 69
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Author Coppo, Mario; Dezani-Ciancaglini, Mariangiola; Giovannetti, Elio; Salvo, Ivano
Title Mobility Types for Mobile Processes in Mobile Ambients Type Journal Article
Year 2003 Publication Electr. Notes Theor. Comput. Sci. Abbreviated Journal
Volume 78 Issue Pages
Keywords
Abstract We present an ambient-like calculus in which the open capability is dropped, and a new form of “lightweight  process mobility is introduced. The calculus comes equipped with a type system that allows the kind of values exchanged in communications and the access and mobility properties of processes to be controlled. A type inference procedure determines the “minimal  requirements to accept a system or a component as well typed. This gives a kind of principal typing. As an expressiveness test, we show that some well known calculi of concurrency and mobility can be encoded in our calculus in a natural way.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved yes
Call Number Sapienza @ mari @ Coppo-Dezani-Giovannetti-Salvo:03 Serial 74
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