2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)最新文献

{"title":"Fast Feature Extraction for Time Series Analysis Using Least-Squares Approximations with Orthogonal Basis Functions","authors":"André Gensler, Thiemo Gruber, B. Sick","doi":"10.1109/TIME.2015.21","DOIUrl":"https://doi.org/10.1109/TIME.2015.21","url":null,"abstract":"Many efforts have been made during the past decades to investigate the use of orthogonal basis functions in the field of least-squares approximation. Certain bases of orthogonal functions allow for a definition of fast update algorithms for approximations of time series in sliding or growing time windows. In fields such as technical data analytics, temporal data mining, or pattern recognition in time series, appropriate time series representations are needed to measure the similarity of time series or to segment them. This article bridges the gap between mathematical basic research and applications by making fast update techniques for standard polynomials and trigonometric polynomials accessible for time series classification or regression (e.g., forecasting), anomaly or motif detection in time series, etc. This is of utmost importance for online or big data applications. Time series or segments of time series will be represented by features derived from the orthogonal expansion coefficients of the approximating polynomials which capture the essential behavior in the time or spectral domain, i.e. trends and periodic behavior, using standard or trigonometric polynomials. Our experiments show that a reliable computation is possible at a very low runtime compared to a conventional least-squares approach. The algorithms are implemented in Java, C(++), Matlab, and Python and made publicly available.","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"146 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123316847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Semantic Vacuity","authors":"Grgur Petric Maretic, M. Dashti, D. Basin","doi":"10.1109/TIME.2015.14","DOIUrl":"https://doi.org/10.1109/TIME.2015.14","url":null,"abstract":"The vacuous satisfaction of a temporal formula with respect to a model has been extensively studied in the literature. Although a universally accepted definition of vacuity does not yet exist, all existing proposals generalize, in one way or another, the antecedent failure of an implication to the syntax of a temporal logic. They are therefore syntactic: whether a model vacuously satisfies a formula is affected by semantics-preserving changes to the formula. This leads to inconsistent and counter-intuitive results. We propose an alternative: a semantic definition of vacuity for LTL where either two semantically equivalent LTL formulas are both satisfied vacuously in a model, or neither of them are. Our definition is based on a syntactic-invariant separation of LTL formulas, which gives rise to an algorithm for detecting semantic vacuity using trap properties. We also propose an alternative algorithm for Buchi automata, which can be used to detect the vacuous satisfaction of omega-regular properties as well as LTL formulas. We analyze this algorithm's worst-case complexity and, using real-world examples, demonstrate that semantic vacuity can be efficiently decided in practice.","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127685052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Price of Evolution in Temporal Databases","authors":"Combi Carlo, Romeo Rizzi, P. Sala","doi":"10.1109/TIME.2015.24","DOIUrl":"https://doi.org/10.1109/TIME.2015.24","url":null,"abstract":"Temporal Functional Dependencies (TFDs for short) are functional dependencies that predicate on temporal databases characterized by a special temporal dimension called valid time (VT). In [1] Combi et al. proposed a uniform framework that subsumes many of the TFDs proposed in literature and, by the combination of them, allow us to express finer constraints. Some interesting constraints are the Temporally Mixed Functional Dependencies (TMFD for short) that allow one to write constraints on the evolution of the data in the database. The problem of checking a TMFD against an instance of a temporal schema is polynomial. We will show that when approximation comes into play (i.e., we look for TMFD holding for almost all database tuples) the problem turns out to be NP-Complete. Moreover we introduce a type of association rules build over TMFD called Temporally Mixed Association Rule (TMAR). We prove that verifying TMAR under approximation is still NP-Complete, by reducing it to a novel problem on directed acyclic graphs.","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132530385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complexity of ITL Model Checking: Some Well-Behaved Fragments of the Interval Logic HS","authors":"A. Molinari, A. Montanari, A. Peron","doi":"10.1109/TIME.2015.12","DOIUrl":"https://doi.org/10.1109/TIME.2015.12","url":null,"abstract":"Model checking has been successfully used in many computer science fields, including artificial intelligence, theoretical computer science, and databases. Most of the proposed solutions make use of classical, point-based temporal logics, while little work has been done in the interval temporal logic setting. Recently, a non-elementary model checking algorithm for Halpern and Shoham's modal logic of time intervals HS over finite Kripke structures (under the homogeneity assumption) and an EXPSPACE model checking procedure for two meaningful fragments of it have been proposed. In this paper, we show that more efficient model checking procedures can be developed for some expressive enough fragments of HS.","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"220 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117000698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Generalizing Allen's Theory of Time to Tree-Like Structures","authors":"Salih Durhan, G. Sciavicco","doi":"10.1109/TIME.2015.17","DOIUrl":"https://doi.org/10.1109/TIME.2015.17","url":null,"abstract":"Allen's Interval Algebra is one of the most prominent formalisms in the area of qualitative temporal (and, by extension, spatial) reasoning. However, its applications are naturally restricted to linear flows of time. While there is some recent work focused on studying relations between intervals (and also between intervals and points) on branching structures, there is no rigorous study of the first-order theory of branching time. In this paper, we approach this problem under a very general definition of time structures as tree-like lattices. Allen's representation theorem shows that \"meets\" is expressively complete for the class of all unbounded linear orders, and it is easy to see that it is also complete for the class of all linear orders. Here we prove that, surprisingly, \"meets\" remains complete for the class of all unbounded tree-like lattices, and we provide an easy axiomatization of the class of all unbounded tree-like lattices in the branching language. Then, we show that \"meets\" becomes incomplete in the class of all tree-like lattices, we give a minimal complete set of three relations for this case along with an axiomatization, which turns out to be particularly challenging to obtain.","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133756705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unifying Sequenced and Non-sequenced Semantics","authors":"C. Dyreson, Venkata A. Rani, Amani Shatnawi","doi":"10.1109/TIME.2015.22","DOIUrl":"https://doi.org/10.1109/TIME.2015.22","url":null,"abstract":"Sequenced and nonsequenced semantics were introduced as different semantics for the evaluation of an operation in a temporal database such as a query or data modification. In this paper we present a new framework that shows both semantics are variants of a general temporal semantics. Our framework uses tuple lineage to track tuples through operations. We present the general semantics and show additional semantics that can be realized. We also show how the semantics can be woven into an operation using annotations.","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115209490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Executable Semantics of Flexible Plans in Terms of Timed Game Automata","authors":"M. C. Mayer, Andrea Orlandini","doi":"10.1109/TIME.2015.16","DOIUrl":"https://doi.org/10.1109/TIME.2015.16","url":null,"abstract":"Robust plan execution in uncertain and dynamic environments is a critical issue for plan-based autonomous systems, especially when uncertain events coexist with temporal flexibility. In this regard, many Planning and Scheduling systems model temporal uncertainty by means of flexible timelines, each of which describes the behavior of one of the system components, and consists of a sequence of events whose begin and end times range within given intervals. This work enriches a previously proposed formal characterization of flexible timelines and plans, considering the difference between controllable and uncontrollable activities. Two main sources of uncertainty are considered: i) some components of the system may depend on an external environment and cannot be planned by the executive, ii) there may be tasks whose duration cannot be exactly foreseen in advance. Such notions are formally defined and the consequent controllability issues are addressed, focusing, in particular, on dynamic controllability. Partially controllable flexible plans are given a semantics in terms of networks of timed game automata (TGA), showing how they can be encoded into such networks. The translation allows for exploiting existing verification tools for TGA, such as UPPAAL-TIGA, in order to check the dynamic controllability property for flexible plans and, possibly, generate a dynamic execution strategy that can be used for robust plan execution. Some preliminary experiments aimed at evaluating the feasibility of the approach are also presented.","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125370660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Global Caching for the Flat Coalgebraic µ-Calculus","authors":"D. Hausmann, Lutz Schröder","doi":"10.1109/TIME.2015.15","DOIUrl":"https://doi.org/10.1109/TIME.2015.15","url":null,"abstract":"Branching-time temporal logics generalizing relational temporal logics such as CTL have been proposed for various system types beyond the purely relational world. This includes, e.g., alternating-time logics, which talk about winning strategies over concurrent game structures, and Parikh's game logic, which is interpreted over monotone neighbourhood frames, as well as probabilistic fixpoint logics. Coalgebraic logic has emerged as a unifying semantic and algorithmic framework for logics featuring generalized modalities of this type. Here, we present a generic global caching algorithm for satisfiability checking in the flat coalgebraic mu-calculus, which realizes known tight exponential-time upper complexity bounds but offers potential for heuristic optimization. It is based on a tableau system that makes do without additional labelling of nodes beyond formulas from the standard Fischer-Ladner closure, such as foci or termination counters for eventualities. Moreover, the tableau system is single-pass, i.e. avoids building an exponential-sized structure in a first pass, to our best knowledge, optimal single-pass systems without numeric time-outs were not previously available even for CTL.","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124263759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Undecidability of Chop","authors":"A. Montanari, Emilio Muñoz-Velasco, G. Sciavicco","doi":"10.1109/TIME.2015.25","DOIUrl":"https://doi.org/10.1109/TIME.2015.25","url":null,"abstract":"The chop operator C is a binary modality that plays an important role in interval temporal logics. Such an operator, which is not definable in Halpern and Shoham's modal logic of time intervals HS, allows one to split an interval into two parts and to specify what is true over them. C appears both in Moszkowski's PITL (that pairs it with a modal constant Pi which is true on all and only the intervals with coincident endpoints) and in Venema's CDT (that also features the binary modalities D and T, and Pi). Without the so-called locality principle, which restricts the semantics of proposition letters, the satisfiability problem for both PITL and CDT turns out to be undecidable over all meaningful classes of linear orders. The problem has been shown to be undecidable also for the fragment C, that is, PITL without Pi, over infinite linear orders. In this paper, we prove that the same holds for C over finite linear orders. To this end, we exploit the close relation between C and the reflexive version of the HS fragment BE, whose modalities correspond to Allen's relations starts and finishes: we prove that the satisfiability problem for reflexive BE is undecidable, undecidability of the same problem for C comes as a corollary.","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128217207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Towards Formal Verification of Distributed Algorithms","authors":"B. Bollig","doi":"10.1109/TIME.2015.23","DOIUrl":"https://doi.org/10.1109/TIME.2015.23","url":null,"abstract":"Model checking is an automatic verification technique, which provides an answer to the question whether a program, given as a state-transition system, satisfies its specification, given in terms of a temporal-logic formula. Model checking is very well studied as far as boolean finite-state programs are concerned [CGP99]. To take into account several sources of infinity such as an unknown number of processes or infinite data structures, the classical setting has been extended in several orthogonal directions. In the context of concurrent programs, one may ask whether a specification is satisfied independently of the number of participating processes. This question is referred to as parameterized verification (see [Esp14] for an overview). Second, a system may have to cope with variables ranging over an infinite domain such as the natural numbers or finite strings. Depending on the operations that are allowed on this domain, system executions can then be described as words over an infinite alphabet, possibly equipped with one or several binary relations such as equality or a total order. Those words are usually referred to as data words [BDM+11], [BMSS09]. Many models and results from both areas, parameterized verification and data words, smoothly extend the classical finite-state approach and, in particular, provide decidable instances of the model checking problem. Our concern in this talk will be distributed algorithms, where an unknown number of (identical) processes cooperate to achieve a common goal. However, assuming perfectly identical processes, even simple tasks such as electing a leader cannot always be accomplished. One may, therefore, assume that every process is equipped with a unique process identifier from an unbounded domain, and that identifiers can be compared with one another wrt. a total order. Thus, when modeling distributed algorithms, one has to cope with both sources of infinity mentioned above: the number of processes and infinite data. This may be one reason why there have been only a few approaches to the formal verification of distributed algorithms [KVW12]. In this talk, we survey recent developments in the areas of parameterized verification and data words, and we demonstrate how they can be exploited towards a framework for the formal verification of distributed algorithms [ABG15].","PeriodicalId":291355,"journal":{"name":"2015 22nd International Symposium on Temporal Representation and Reasoning (TIME)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117280497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}