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The twenty-ninth edition of the SEBD (Italian Symposium on Advanced Database Systems), held on 5-9 September 2021 in Pizzo (Calabria Region, Italy), included a joint seminar on “Reminiscence of TIDB 1981” with invited talks given by some of the participants to the Advanced Seminar on Theoretical Issues in Databases (TIDB), which took place in the same region exactly forty years earlier. The joint seminar was concluded by a Panel on “The Past and the Future of Computer Science Theory” with the participation of four distinguished computer science theorists (Ronald Fagin, Georg Gottlob, Christos Papadimitriou and Moshe Vardi), who were interviewed by Giorgio Ausiello, Maurizio Lenzerini, Luigi Palopoli, Domenico Saccà and Francesco Scarcello. This paper reports the summaries of the four interviews.

Do agents know each others' strategies? In multi-process software construction, each process has access to the processes already constructed; but in typical human-robot interactions, a human may not announce their strategy to the robot (indeed, the human may not even know their own strategy). This question has often been overlooked when modeling and reasoning about multi-agent systems. In this work we study how it impacts strategic reasoning. To do so we consider Strategy Logic (SL), a well-established and highly expressive logic for strategic reasoning. Its usual semantics, which we call “white-box semantics”, models systems in which agents “broadcast” their strategies. By adding imperfect information to the evaluation games for the usual semantics, we obtain a new semantics called “black-box semantics”, in which agents keep their strategies private. We consider the model-checking problem and show that the black-box semantics has much lower complexity than white-box semantics for an important fragment of Strategy Logic.

In this paper, we model manufacturing processes and facilities as transducers (automata with output). The problem of whether a given manufacturing process can be realized by a given set of manufacturing resources can then be stated as an orchestration problem for transducers. We first consider the conceptually simpler case of uni-transducers (transducers with a single input and a single output port), and show that synthesizing orchestrations for uni-transducers is EXPTIME-complete. Surprisingly, the complexity remains the same for the more expressive multi-transducer case, where transducers have multiple input and output ports and the orchestration is in charge of dynamically connecting ports during execution.

The specification of complex motion goals through temporal logics is increasingly favored in robotics to narrow the gap between task and motion planning. A major limiting factor of such logics, however, is their Boolean satisfaction condition. To relax this limitation, we introduce a method for quantifying the satisfaction of co-safe linear temporal logic specifications, and propose a planner that uses this method to synthesize robot trajectories with the optimal satisfaction value. The method assigns costs to violations of specifications from user-defined proposition costs. These violation costs define a distance to satisfaction and can be computed algorithmically using a weighted automaton. The planner utilizes this automaton and an abstraction of the robotic system to construct a product graph that captures all possible robot trajectories and their distances to satisfaction. Then, a plan with the minimum distance to satisfaction is generated by employing this graph as the high-level planner in a synergistic planning framework. The efficacy of the method is illustrated on a robot with unsatisfiable specifications in an office environment.

Introduction: Hospitalised patients in Internal Medicine departments are at risk of venous thromboembolism (VTE). Adherence to risk stratification methods is poor. We conducted a survey among Internists from member countries of the European Federation of Internal Medicine (EFIM) to assess current knowledge and attitude towards VTE prevention. Methods: A multinational survey of Internists affiliated to EFIM. Results: 226 physicians from 30 countries were included. Seventy nine percent of the physicians were aware of clinical guidelines to prevent VTE. Most considered their knowledge of the guidelines to be moderate. Many had not updated their knowledge recently. The magnitude of the clinical problem was over-and underestimated by many (12.2% and 40.1%, respectively). Only 46.7% thought their patients were mostly receiving proper prophylaxis. Sixty four percent worked in departments without a formal VTE prophylaxis program. Risk of bleeding, lack of awareness and lack of decision support systems were the three most common reasons for deferring treatment (88.6%, 32.3% and 27.9%, respectively). Most of the participants stated that they strongly believe in VTE prophylaxis as an intervention that prevents morbidity and mortality. Conclusions: Despite general awareness of clinical guidelines, many medical wards do not have formal risk assessment methodologies incorporated into their operative workflow. This gap, as well as fear of complications, may be one of the reasons for the low rates of adherence reported by physicians. We speculate that perhaps current guidelines have not been accepted by Internists due to paucity of well defined and validated risk assessment tools. (C) 2011 Elsevier Ltd. All rights reserved.

The study of node-selection query languages for (finite) trees has been a major topic in the recent research on query lan- guages for Web documents. On one hand, there has been an extensive study of XPath and its various extensions. On the other hand, query languages based on classical logics, such as first-order logic (FO) or monadic second-order logic (MSO), have been considered. Results in this area typically relate an Xpath-based language to a classical logic. What has yet to emerge is an XPath-related language that is expressive as MSO, and at the same time enjoys the computational proper- ties of XPath, which are linear query evaluation and exponen- tial query-containment test. In this paper we propose μXPath, which is the alternation-free fragment of XPath extended with fixpoint operators. Using two-way alternating automata, we show that this language does combine desired expressiveness and computational properties, placing it as an attractive can- didate as the definite query language for trees.