Mixed computation

2021 ◽  
Vol 3 (2) ◽  
pp. 215-244
Author(s):  
Diego Gabriel Krivochen
Keyword(s):  
Computational Complexity ◽  
Natural Language ◽  
Phrase Structure ◽  
Explicit Characterization ◽  
Tree Adjoining Grammar ◽  
Branching Trees ◽  
Structural Descriptions ◽  
Context Free ◽  
The Way

Abstract Proof-theoretic models of grammar are based on the view that an explicit characterization of a language comes in the form of the recursive enumeration of strings in that language. That recursive enumeration is carried out by a procedure which strongly generates a set of structural descriptions Σ and weakly generates a set of strings S; a grammar is thus a function that pairs an element of Σ with elements of S. Structural descriptions are obtained by means of Context-Free phrase structure rules or via recursive combinatorics and structure is assumed to be uniform: binary branching trees all the way down. In this work we will analyse natural language constructions for which such a rigid conception of phrase structure is descriptively inadequate and propose a solution for the problem of phrase structure grammars assigning too much or too little structure to natural language strings: we propose that the grammar can oscillate between levels of computational complexity in local domains, which correspond to elementary trees in a lexicalised Tree Adjoining Grammar.

scholarly journals Point configurations, phylogenetic trees, and dissimilarity vectors

2021 ◽  
Vol 118 (12) ◽  
pp. e2021244118
Author(s):  
Alessio Caminata ◽  
Noah Giansiracusa ◽  
Han-Bom Moon ◽  
Luca Schaffler
Keyword(s):  
Phylogenetic Trees ◽  
Geometric Interpretation ◽  
Explicit Characterization ◽  
Point Configurations ◽  
Definition Of ◽  
Tropical Basis ◽  
The Way

In 2004, Pachter and Speyer introduced the higher dissimilarity maps for phylogenetic trees and asked two important questions about their relation to the tropical Grassmannian. Multiple authors, using independent methods, answered affirmatively the first of these questions, showing that dissimilarity vectors lie on the tropical Grassmannian, but the second question, whether the set of dissimilarity vectors forms a tropical subvariety, remained opened. We resolve this question by showing that the tropical balancing condition fails. However, by replacing the definition of the dissimilarity map with a weighted variant, we show that weighted dissimilarity vectors form a tropical subvariety of the tropical Grassmannian in exactly the way that Pachter and Speyer envisioned. Moreover, we provide a geometric interpretation in terms of configurations of points on rational normal curves and construct a finite tropical basis that yields an explicit characterization of weighted dissimilarity vectors.

On syntactic categories

1981 ◽  
Vol 295 (1077) ◽  
pp. 267-283 ◽  
Keyword(s):  
Natural Language ◽  
General Type ◽  
Phrase Structure ◽  
Negative Answer ◽  
Syntactic Category ◽  
Quarter Century ◽  
Context Free

A traditional concern of grammarians has been the question of whether the members of given pairs of expressions belong to the same or different syntactic categories. Consider the following example sentences. ( a ) I think Fido destroyed the kennel . ( b ) The kennel, I think Fido destroyed . Are the two underlined expressions members of the same syntactic category or not? The generative grammarians of the last quarter century have, almost without exception, taken the answer to be affirmative. In the present paper I explore the implications of taking the answer to be negative. The changes consequent upon this negative answer turn out to be very far-reaching: (i) it becomes as simple to state rules for constructions of the general type exemplified in ( b ) as it is for the canonical NP VP construction in ( a ); (ii) we immediately derive an explanation for a range of coordination facts that have remained quite mysterious since they were discovered by J. R. Ross some 15 years ago; (iii) our grammars can entirely dispense with the class of rules known as transformations; (iv) our grammars can be shown to be formally equivalent to what are known as the context-free phrase structure grammars; (v) this latter consequence has the effect of making potentially relevant to natural language grammars a whole literature of mathematical results on the parsability and learnability of context-free phrase structure grammars.

scholarly journals 100 years of Debye's scattering equation

2016 ◽  
Vol 72 (6) ◽  
pp. 608-620 ◽  
Author(s):  
Luca Gelisio ◽  
Paolo Scardi
Keyword(s):  
Quantum Mechanics ◽  
Computational Complexity ◽  
State Of The Art ◽  
Scientific Development ◽  
Total Scattering ◽  
Accurate Representation ◽  
Atoms And Molecules ◽  
Atomic Distance ◽  
The Way

Debye's scattering equation (DSE) has spanned a century of scientific development, from the dawn of quantum mechanics and the investigation of the structure of atoms and molecules to the era of nanotechnology, paving the way tototal scatteringmethods. The formulation offers the most accurate representation of the intensity scattered by randomly oriented atomic aggregates, constructed by superimposing the signal from each atomic distance in the molecule. The present paper reviews some of the milestone applications, from the interpretation of the intensity curves from gases and vapours, to aggregates of increasing size and more extended order. Important developments, aimed at mitigating the prohibitive computational complexity of the DSE, and state-of-the-art methods for the characterization of static and dynamic displacements are also discussed.

scholarly journals Towards Automated Semantic Explainability of Multimedia Feature Graphs

Information ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 502
Author(s):  
Stefan Wagenpfeil ◽  
Paul Mc Kevitt ◽  
Matthias Hemmje
Keyword(s):  
Natural Language ◽  
Phrase Structure ◽  
Formal Context ◽  
Semantic Model ◽  
Analysis Framework ◽  
Production Rules ◽  
Phrase Structure Grammar ◽  
Semantic Extension ◽  
Context Free ◽  
Multimedia Features

Multimedia feature graphs are employed to represent features of images, video, audio, or text. Various techniques exist to extract such features from multimedia objects. In this paper, we describe the extension of such a feature graph to represent the meaning of such multimedia features and introduce a formal context-free PS-grammar (Phrase Structure grammar) to automatically generate human-understandable natural language expressions based on such features. To achieve this, we define a semantic extension to syntactic multimedia feature graphs and introduce a set of production rules for phrases of natural language English expressions. This explainability, which is founded on a semantic model provides the opportunity to represent any multimedia feature in a human-readable and human-understandable form, which largely closes the gap between the technical representation of such features and their semantics. We show how this explainability can be formally defined and demonstrate the corresponding implementation based on our generic multimedia analysis framework. Furthermore, we show how this semantic extension can be employed to increase the effectiveness in precision and recall experiments.

PRINCIPAL PROBLEMS OF NATURAL LANGUAGE PROCESSING SYSTEMS

2018 ◽  
pp. 35-38
Author(s):  
O. Hyryn
Keyword(s):  
Natural Language Processing ◽  
Natural Language ◽  
Language Processing ◽  
Syntactic Analysis ◽  
Syntactic Ambiguity ◽  
Grammatical Structure ◽  
English Sentence ◽  
Analysis Methods ◽  
The Way

The article deals with natural language processing, namely that of an English sentence. The article describes the problems, which might arise during the process and which are connected with graphic, semantic, and syntactic ambiguity. The article provides the description of how the problems had been solved before the automatic syntactic analysis was applied and the way, such analysis methods could be helpful in developing new analysis algorithms. The analysis focuses on the issues, blocking the basis for the natural language processing — parsing — the process of sentence analysis according to their structure, content and meaning, which aims to analyze the grammatical structure of the sentence, the division of sentences into constituent components and defining links between them.

Shakespeare Afoot

2018 ◽  
Author(s):  
John Kerrigan
Keyword(s):  
Early Modern ◽  
Richard Iii ◽  
Midsummer Night's Dream ◽  
As You Like It ◽  
A Midsummer Night's Dream ◽  
History Of ◽  
The Way

That Shakespeare adds a limp to the received characterization of Richard III is only the most conspicuous instance of his interest in how actors walked, ran, danced, and wandered. His attention to actors’ footwork, as an originating condition of performance, can be traced from Richard III through A Midsummer Night’s Dream and As You Like It into Macbeth, which is preoccupied with the topic and activity all the way to the protagonist’s melancholy conclusion that ‘Life’s but a walking shadow, a poor player | That struts and frets his hour upon the stage’. Drawing on classical and early modern accounts of how people walk and should walk, on ideas about time and prosody, and the experience of disability, this chapter cites episodes in the history of performance to show how actors, including Alleyn, Garrick, and Olivier, have worked with the opportunities to dramatize footwork that are provided by Shakespeare’s plays.

scholarly journals Does higher education properly prepare graduates for the growing artificial intelligence market? Gaps identification using text mining

2021 ◽  
pp. 1-13
Author(s):  
Lamiae Benhayoun ◽  
Daniel Lang
Keyword(s):  
Artificial Intelligence ◽  
Natural Language Processing ◽  
Text Mining ◽  
Natural Language ◽  
Language Processing ◽  
Academic Training ◽  
Market Requirements ◽  
Job Advertisements ◽  
The Individual

BACKGROUND: The renewed advent of Artificial Intelligence (AI) is inducing profound changes in the classic categories of technology professions and is creating the need for new specific skills. OBJECTIVE: Identify the gaps in terms of skills between academic training on AI in French engineering and Business Schools, and the requirements of the labour market. METHOD: Extraction of AI training contents from the schools’ websites and scraping of a job advertisements’ website. Then, analysis based on a text mining approach with a Python code for Natural Language Processing. RESULTS: Categorization of occupations related to AI. Characterization of three classes of skills for the AI market: Technical, Soft and Interdisciplinary. Skills’ gaps concern some professional certifications and the mastery of specific tools, research abilities, and awareness of ethical and regulatory dimensions of AI. CONCLUSIONS: A deep analysis using algorithms for Natural Language Processing. Results that provide a better understanding of the AI capability components at the individual and the organizational levels. A study that can help shape educational programs to respond to the AI market requirements.

scholarly journals Compact Differences of Composition Operators on Bergman Spaces Induced by Doubling Weights

2021 ◽  
Author(s):  
Bin Liu ◽  
Jouni Rättyä ◽  
Fanglei Wu
Keyword(s):  
Bergman Space ◽  
Open Problem ◽  
Lebesgue Space ◽  
Composition Operators ◽  
Bergman Spaces ◽  
Weighted Bergman Space ◽  
Carleson Measures ◽  
Doubling Weights ◽  
The Way

AbstractBounded and compact differences of two composition operators acting from the weighted Bergman space $$A^p_\omega $$ A ω p to the Lebesgue space $$L^q_\nu $$ L ν q , where $$0<q<p<\infty $$ 0 < q < p < ∞ and $$\omega $$ ω belongs to the class "Equation missing" of radial weights satisfying two-sided doubling conditions, are characterized. On the way to the proofs a new description of q-Carleson measures for $$A^p_\omega $$ A ω p , with $$p>q$$ p > q and "Equation missing", involving pseudohyperbolic discs is established. This last-mentioned result generalizes the well-known characterization of q-Carleson measures for the classical weighted Bergman space $$A^p_\alpha $$ A α p with $$-1<\alpha <\infty $$ - 1 < α < ∞ to the setting of doubling weights. The case "Equation missing" is also briefly discussed and an open problem concerning this case is posed.

Microbrook, Mesobrook, Macrobrook

2019 ◽  
Vol 2 (4) ◽  
pp. 245-253 ◽  
Author(s):  
Sebastian Jilke ◽  
Asmus Leth Olsen ◽  
William Resh ◽  
Saba Siddiki
Keyword(s):  
Problem Solving ◽  
Public Administration ◽  
Theory And Practice ◽  
Levels Of Analysis ◽  
Explicit Characterization ◽  
Methodological Perspective ◽  
Level Of Analysis ◽  
Effective Problem

Abstract This article assesses the field of public administration from a conceptual and methodological perspective. We urge public administration scholars to resolve the ambiguities that mire our scholarship due to the inadequate treatment of levels of analysis in our research. Overall, we encourage methodological accountability through a more explicit characterization of one’s research by the level of analysis to which it relates. We argue that this particular form of accountability is critical for effective problem solving for advancing theory and practice.

scholarly journals Controllability of Continuous Bimodal Linear Systems

2013 ◽  
Vol 2013 ◽  
pp. 1-14 ◽  
Author(s):  
Josep Ferrer ◽  
Juan R. Pacha ◽  
Marta Peña
Keyword(s):  
Linear Systems ◽  
Higher Dimensions ◽  
Linear Dynamics ◽  
Explicit Characterization ◽  
Separating Hyperplane

We consider bimodal linear systems consisting of two linear dynamics acting on each side of a given hyperplane, assuming continuity along the separating hyperplane. We prove that the study of controllability can be reduced to the unobservable case, and for these ones we obtain a simple explicit characterization of controllability for dimensions 2 and 3, as well as some partial criteria for higher dimensions.

Sign in / Sign up

Export Citation Format

Share Document