17,784 research outputs found
Controllability in partial and uncertain environments
© 2014 IEEE.Controller synthesis is a well studied problem that attempts to automatically generate an operational behaviour model of the system-to-be that satisfies a given goal when deployed in a given domain model that behaves according to specified assumptions. A limitation of many controller synthesis techniques is that they require complete descriptions of the problem domain. This is limiting in the context of modern incremental development processes when a fully described problem domain is unavailable, undesirable or uneconomical. Previous work on Modal Transition Systems (MTS) control problems exists, however it is restricted to deterministic MTSs and deterministic Labelled Transition Systems (LTS) implementations. In this paper we study the Modal Transition System Control Problem in its full generality, allowing for nondeterministic MTSs modelling the environments behaviour and nondeterministic LTS implementations. Given an nondeterministic MTS we ask if all, none or some of the nondeterministic LTSs it describes admit an LTS controller that guarantees a given property. We show a technique that solves effectively the MTS realisability problem and it can be, in some cases, reduced to deterministic control problems. In all cases the MTS realisability problem is in same complexity class as the corresponding LTS problem
Technological prerequisites for indistinguishability of a person and his/her computer replica
Some people wrongly believe that A. Turing’s works that underlie all modern computer science never discussed “physical” robots. This is not so, since Turing did speak about such machines, though making a reservation that this discussion was still premature. In particular, in his 1948 report [8], he suggested that a physical intelligent machine equipped with motors, cameras and loudspeakers, when wandering through the fields of England, would present “the danger to the ordinary citizen would be serious.” [8, ]. Due to this imperfection of technology in the field of knowledge that we now call robotics, the methodology that he proposed was based on human speech, or rather on text. Other natural human skills were too difficult to implement, while the exchange of cues via written messages was much more accessible for engineering implementation in Turing’s time. Nevertheless, since then, the progress of computer technology has taken forms that the founder of artificial intelligence could not have foreseen
Good Applications for Crummy Entity Linkers? The Case of Corpus Selection in Digital Humanities
Over the last decade we have made great progress in entity linking (EL)
systems, but performance may vary depending on the context and, arguably, there
are even principled limitations preventing a "perfect" EL system. This also
suggests that there may be applications for which current "imperfect" EL is
already very useful, and makes finding the "right" application as important as
building the "right" EL system. We investigate the Digital Humanities use case,
where scholars spend a considerable amount of time selecting relevant source
texts. We developed WideNet; a semantically-enhanced search tool which
leverages the strengths of (imperfect) EL without getting in the way of its
expert users. We evaluate this tool in two historical case-studies aiming to
collect a set of references to historical periods in parliamentary debates from
the last two decades; the first targeted the Dutch Golden Age, and the second
World War II. The case-studies conclude with a critical reflection on the
utility of WideNet for this kind of research, after which we outline how such a
real-world application can help to improve EL technology in general.Comment: Accepted for presentation at SEMANTiCS '1
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