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VOX : an extensible natural language processor
VOX is a Natural Language Processor whose knowledge can be extended by interaction with a user.VOX consists of a text analyzer and an extensibility system that share a knowledge base. The extensibility system lets the user add vocabulary, concepts, phrases, events, and scenarios to the knowledge base. The analyzer uses information obtained in this way to understand previously unhandled text.The underlying knowledge representation of VOX, called Conceptual Grammar, has been developed to meet the severe requirements of extensibility. Conceptual Grammar uniformly represents syntactic and semantic information, and permits modular addition of knowledge
Trading inference effort versus size in CNF Knowledge Compilation
Knowledge Compilation (KC) studies compilation of boolean functions f into
some formalism F, which allows to answer all queries of a certain kind in
polynomial time. Due to its relevance for SAT solving, we concentrate on the
query type "clausal entailment" (CE), i.e., whether a clause C follows from f
or not, and we consider subclasses of CNF, i.e., clause-sets F with special
properties. In this report we do not allow auxiliary variables (except of the
Outlook), and thus F needs to be equivalent to f.
We consider the hierarchies UC_k <= WC_k, which were introduced by the
authors in 2012. Each level allows CE queries. The first two levels are
well-known classes for KC. Namely UC_0 = WC_0 is the same as PI as studied in
KC, that is, f is represented by the set of all prime implicates, while UC_1 =
WC_1 is the same as UC, the class of unit-refutation complete clause-sets
introduced by del Val 1994. We show that for each k there are (sequences of)
boolean functions with polysize representations in UC_{k+1}, but with an
exponential lower bound on representations in WC_k. Such a separation was
previously only know for k=0. We also consider PC < UC, the class of
propagation-complete clause-sets. We show that there are (sequences of) boolean
functions with polysize representations in UC, while there is an exponential
lower bound for representations in PC. These separations are steps towards a
general conjecture determining the representation power of the hierarchies PC_k
< UC_k <= WC_k. The strong form of this conjecture also allows auxiliary
variables, as discussed in depth in the Outlook.Comment: 43 pages, second version with literature updates. Proceeds with the
separation results from the discontinued arXiv:1302.442
Numerical study of the urban geometrical representation impact in a surface energy budget model
The aim of this work is to investigate how both the orientation of the urban canyon and the modeling of the edge effects (i.e. urban canyons of finite length) are important in the numerical simulation of the surface energy budget in urban areas. Starting from the town energy balance scheme, two models of increasing complexity of the canyon geometry are developed. A sensitivity analysis of the role played by the chosen hypothesis and parameterizations is performed by coupling the canyon schemes with the numerical weather prediction model RAMS. The results suggest that a detailed description of the urban geometry could produce non-negligible differences of the energy balances and of the temperature fields with respect to what occurs using simpler schematizations, in particular during the summer
Scientia intuitiva in the Ethics
**For my more recent views of the third kind of cognition, see my "Finding Oneself in God"**
Abstract: Cognition of the third kind, or scientia intuitiva, is supposed to secure beatitudo, or virtue itself (E5p42). But what is scientia intuitiva, and how is it different from (and superior to) reason? I suggest a new answer to this old and vexing question at the core of Spinoza’s project in the Ethics. On my view, Spinoza’s scientia intuitiva resembles Descartes’s scientia more than has been appreciated. Although Spinoza’s God is not Descartes’s benevolent, transcendent God, Spinoza agrees with Descartes that the highest certainty requires that a cognizer correctly conceive of God and her causal relation to God; it is only with cognition of the third kind that a cognizer can be certain that her adequate (that is, clear and distinct) representations of extramental things agree with formally real, extramental ideata, and so are true. If this is right, a reading of Spinoza that has dominated scholarship since the Ethics’ publication is misguided: for Spinoza, it is not always the case that having (and recognizing that one has) a clear and distinct idea is sufficient for knowing that that idea is true. I end the chapter by suggesting why scientia is intuitive for Spinoza: Spinoza attempts to avoid Cartesian-Circle-style circularity by insisting that a cognizer must intuit the correct representation of God and God’s relation to things
Quantum Structures: An Attempt to Explain the Origin of their Appearance in Nature
We explain the quantum structure as due to the presence of two effects, (a) a
real change of state of the entity under influence of the measurement and, (b)
a lack of knowledge about a deeper deterministic reality of the measurement
process. We present a quantum machine, where we can illustrate in a simple way
how the quantum structure arises as a consequence of the two mentioned effects.
We introduce a parameter epsilon that measures the size of the lack of
knowledge on the measurement process, and by varying this parameter, we
describe a continuous evolution from a quantum structure (maximal lack of
knowledge) to a classical structure (zero lack of knowledge). We show that for
intermediate values of epsilon we find a new type of structure, that is neither
quantum nor classical. We apply the model that we have introduced to situations
of lack of knowledge about the measurement process appearing in other regions
of reality. More specifically we investigate the quantum-like structures that
appear in the situation of psychological decision processes, where the subject
is influenced during the testing, and forms some of his opinions during the
testing process. Our conclusion is that in the light of this explanation, the
quantum probabilities are epistemic and not ontological, which means that
quantum mechanics is compatible with a determinism of the whole.Comment: 22 pages, 8 figure
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