EFFICIENT DETERMINISTIC FINITE AUTOMATA SPLIT-MINIMIZATION DERIVED FROM BRZOZOWSKI'S ALGORITHM

Minimization of deterministic finite automata is a classic problem in Computer Science which is still studied nowadays. In this paper, we relate the different split-minimization methods proposed to date, or to be proposed, and the algorithm due to Brzozowski which has been usually set aside in any classification of DFA minimization algorithms. In our work, we first propose a polynomial minimization method derived from a paper by Champarnaud et al. We also show how the consideration of some efficiency improvements on this algorithm lead to obtain an algorithm similar to Hopcroft's classic algorithm. The results obtained lead us to propose a characterization of the set of possible splitters.

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On the algorithmic complexity of crystals

Mineralogical Magazine ◽

10.1180/minmag.2014.078.2.12 ◽

2014 ◽

Vol 78 (2) ◽

pp. 415-435 ◽

Cited By ~ 5

Author(s):

S. V. Krivovichev

Keyword(s):

Computer Science ◽

Coordination Polymers ◽

Finite Automata ◽

Theoretical Computer Science ◽

Algorithmic Complexity ◽

Inorganic Materials ◽

Important Class ◽

Theoretical Computer ◽

Deterministic Finite Automata ◽

Orthogonal Networks

AbstractThe concept of the algorithmic complexity of crystals is developed for a particular class of minerals and inorganic materials based on orthogonal networks, which are defined as networks derived from the primitive cubic net (pcu) by the removal of some vertices and/or edges. Orthogonal networks are an important class of networks that dominate topologies of inorganic oxysalts, framework silicates and aluminosilicate minerals, zeolites and coordination polymers. The growth of periodic orthogonal networks may be modelled using structural automata, which are finite automata with states corresponding to vertex configurations and transition symbols corresponding to the edges linking the respective vertices. The model proposed describes possible relations between theoretical crystallography and theoretical computer science through the theory of networks and the theory of deterministic finite automata.

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Minimal Reversible Deterministic Finite Automata

International Journal of Foundations of Computer Science ◽

10.1142/s0129054118400063 ◽

2018 ◽

Vol 29 (02) ◽

pp. 251-270 ◽

Cited By ~ 4

Author(s):

Markus Holzer ◽

Sebastian Jakobi ◽

Martin Kutrib

Keyword(s):

Lower Bounds ◽

Finite Automata ◽

Transition Function ◽

Upper And Lower Bounds ◽

State Graph ◽

Deterministic Finite Automata ◽

Injective Mapping ◽

Pattern Approach ◽

Almost All

We study reversible deterministic finite automata (REV-DFAs), that are partial deterministic finite automata whose transition function induces an injective mapping on the state set for every letter of the input alphabet. We give a structural characterization of regular languages that can be accepted by REV-DFAs. This characterization is based on the absence of a forbidden pattern in the (minimal) deterministic state graph. Again with a forbidden pattern approach, we also show that the minimality of REV-DFAs among all equivalent REV-DFAs can be decided. Both forbidden pattern characterizations give rise to [Formula: see text]-complete decision algorithms. In fact, our techniques allow us to construct the minimal REV-DFA for a given minimal DFA. These considerations lead to asymptotic upper and lower bounds on the conversion from DFAs to REV-DFAs. Thus, almost all problems that concern uniqueness and the size of minimal REV-DFAs are solved.

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Two Extensions of Cover Automata

Axioms ◽

10.3390/axioms10040338 ◽

2021 ◽

Vol 10 (4) ◽

pp. 338

Author(s):

Cezar Câmpeanu

Keyword(s):

Computational Complexity ◽

Finite Automata ◽

The State ◽

Finite Cover ◽

Deterministic Finite Automata ◽

State Complexity ◽

Compact Representations ◽

Minimization Algorithms ◽

Deterministic Automata ◽

Representation Transformation

Deterministic Finite Cover Automata (DFCA) are compact representations of finite languages. Deterministic Finite Automata with “do not care” symbols and Multiple Entry Deterministic Finite Automata are both compact representations of regular languages. This paper studies the benefits of combining these representations to get even more compact representations of finite languages. DFCAs are extended by accepting either “do not care” symbols or considering multiple entry DFCAs. We study for each of the two models the existence of the minimization or simplification algorithms and their computational complexity, the state complexity of these representations compared with other representations of the same language, and the bounds for state complexity in case we perform a representation transformation. Minimization for both models proves to be NP-hard. A method is presented to transform minimization algorithms for deterministic automata into simplification algorithms applicable to these extended models. DFCAs with “do not care” symbols prove to have comparable state complexity as Nondeterministic Finite Cover Automata. Furthermore, for multiple entry DFCAs, we can have a tight estimate of the state complexity of the transformation into equivalent DFCA.

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OPTIMAL HYPER-MINIMIZATION

International Journal of Foundations of Computer Science ◽

10.1142/s0129054111009094 ◽

2011 ◽

Vol 22 (08) ◽

pp. 1877-1891 ◽

Cited By ~ 7

Author(s):

ANDREAS MALETTI ◽

DANIEL QUERNHEIM

Keyword(s):

Experimental Study ◽

Finite Number ◽

Open Problem ◽

Finite Automata ◽

Finite State Automata ◽

Deterministic Finite Automata ◽

Deterministic Automaton ◽

Finite State ◽

Minimization Algorithms ◽

Run Time

Minimal deterministic finite automata (DFAs) can be reduced further at the expense of a finite number of errors. Recently, such minimization algorithms have been improved to run in time O(n log n), where n is the number of states of the input DFA, by [GAWRYCHOWSKI and JEŻ: Hyper-minimisation made efficient. Proc. MFCS, LNCS 5734, 2009] and [HOLZER and MALETTI: An n log n algorithm for hyper-minimizing a (minimized) deterministic automaton. Theor. Comput. Sci. 411, 2010]. Both algorithms return a DFA that is as small as possible, while only committing a finite number of errors. These algorithms are further improved to return a DFA that commits the least number of errors at the expense of an increased (quadratic) run-time. This solves an open problem of [BADR, GEFFERT, and SHIPMAN: Hyper-minimizing minimized deterministic finite state automata. RAIRO Theor. Inf. Appl. 43, 2009]. In addition, an experimental study on random automata is performed and the effects of the existing algorithms and the new algorithm are reported.

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An efficient incremental DFA minimization algorithm

Natural Language Engineering ◽

10.1017/s1351324903003127 ◽

2003 ◽

Vol 9 (1) ◽

pp. 49-64 ◽

Cited By ~ 21

Author(s):

BRUCE W. WATSON ◽

JAN DACIUK

Keyword(s):

Large Class ◽

Finite Automata ◽

Time Algorithm ◽

The Other ◽

Minimization Algorithm ◽

Worst Case ◽

Deterministic Finite Automata ◽

Running Time ◽

The Third ◽

Minimization Algorithms

In this paper, we present a new Deterministic Finite Automata (DFA) minimization algorithm. The algorithm is incremental – it may be halted at any time, yielding a partially-minimized automaton. All of the other (known) minimization algorithms have intermediate results which are not useable for partial minimization. Since the first algorithm is easily understood but inefficient, we consider three practical and effective optimizations. The first two optimizations do not affect the asymptotic worst-case running time – though they perform well on a large class of automata. The third optimization yields an quadratic-time algorithm which is competitive with the previously known ones.

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ABOUT THE PROBLEM OF CLASSIFICATION OF THE CONCEPTS OF INFORMATICS STUDIED AT SECONDARY SCHOOL

Informatics in school ◽

10.32517/2221-1993-2018-17-7-4-7 ◽

2018 ◽

pp. 4-7

Author(s):

S. I. Zenko

Keyword(s):

Secondary School ◽

Foreign Language ◽

Computer Science ◽

Parts Of Speech ◽

The Third ◽

The Cross ◽

Definition Of

The article raises the problem of classification of the concepts of computer science and informatics studied at secondary school. The efficiency of creation of techniques of training of pupils in these concepts depends on its solution. The author proposes to consider classifications of the concepts of school informatics from four positions: on the cross-subject basis, the content lines of the educational subject "Informatics", the logical and structural interrelations and interactions of the studied concepts, the etymology of foreign-language and translated words in the definition of the concepts of informatics. As a result of the first classification general and special concepts are allocated; the second classification — inter-content and intra-content concepts; the third classification — stable (steady), expanding, key and auxiliary concepts; the fourth classification — concepts-nouns, conceptsverbs, concepts-adjectives and concepts — combinations of parts of speech.

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Morphological and Ultrastructural Characterization of Hemocytes in an Insect Model, the Hematophagous Dipetalogaster maxima (Hemiptera: Reduviidae)

Insects ◽

10.3390/insects12070640 ◽

2021 ◽

Vol 12 (7) ◽

pp. 640

Author(s):

Natalia R. Moyetta ◽

Fabián O. Ramos ◽

Jimena Leyria ◽

Lilián E. Canavoso ◽

Leonardo L. Fruttero

Keyword(s):

Cell Biology ◽

Cell Types ◽

Transmission Electron ◽

Ultrastructural Characterization ◽

Current Classification ◽

Contrast Microscopy ◽

First Time ◽

Controversial Aspect

Hemocytes, the cells present in the hemolymph of insects and other invertebrates, perform several physiological functions, including innate immunity. The current classification of hemocyte types is based mostly on morphological features; however, divergences have emerged among specialists in triatomines, the insect vectors of Chagas’ disease (Hemiptera: Reduviidae). Here, we have combined technical approaches in order to characterize the hemocytes from fifth instar nymphs of the triatomine Dipetalogaster maxima. Moreover, in this work we describe, for the first time, the ultrastructural features of D. maxima hemocytes. Using phase contrast microscopy of fresh preparations, five hemocyte populations were identified and further characterized by immunofluorescence, flow cytometry and transmission electron microscopy. The plasmatocytes and the granulocytes were the most abundant cell types, although prohemocytes, adipohemocytes and oenocytes were also found. This work sheds light on a controversial aspect of triatomine cell biology and physiology setting the basis for future in-depth studies directed to address hemocyte classification using non-microscopy-based markers.

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Semi-automated regional classification of the style of activity of slow rock-slope deformations using PS InSAR and SqueeSAR velocity data

Landslides ◽

10.1007/s10346-021-01654-0 ◽

2021 ◽

Author(s):

Chiara Crippa ◽

Elena Valbuzzi ◽

Paolo Frattini ◽

Giovanni B. Crosta ◽

Margherita C. Spreafico ◽

...

Keyword(s):

Rock Slope ◽

Progressive Failure ◽

Principal Component ◽

Cost Effective ◽

Displacement Rate ◽

Machine Learning Classification ◽

Management Perspective ◽

Alpine Environments

AbstractLarge slow rock-slope deformations, including deep-seated gravitational slope deformations and large landslides, are widespread in alpine environments. They develop over thousands of years by progressive failure, resulting in slow movements that impact infrastructures and can eventually evolve into catastrophic rockslides. A robust characterization of their style of activity is thus required in a risk management perspective. We combine an original inventory of slow rock-slope deformations with different PS-InSAR and SqueeSAR datasets to develop a novel, semi-automated approach to characterize and classify 208 slow rock-slope deformations in Lombardia (Italian Central Alps) based on their displacement rate, kinematics, heterogeneity and morphometric expression. Through a peak analysis of displacement rate distributions, we characterize the segmentation of mapped landslides and highlight the occurrence of nested sectors with differential activity and displacement rates. Combining 2D decomposition of InSAR velocity vectors and machine learning classification, we develop an automatic approach to characterize the kinematics of each landslide. Then, we sequentially combine principal component and K-medoids cluster analyses to identify groups of slow rock-slope deformations with consistent styles of activity. Our methodology is readily applicable to different landslide datasets and provides an objective and cost-effective support to land planning and the prioritization of local-scale studies aimed at granting safety and infrastructure integrity.

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The Underlying Order Induced by Orthogonality and the Quantum Speed Limit

Quantum Reports ◽

10.3390/quantum3030024 ◽

2021 ◽

Vol 3 (3) ◽

pp. 376-388

Author(s):

Francisco J. Sevilla ◽

Andrea Valdés-Hernández ◽

Alan J. Barrios

Keyword(s):

Energy Spectrum ◽

Energy Distribution ◽

Finite Time ◽

Complete Characterization ◽

Comprehensive Analysis ◽

Orthogonality Condition ◽

Speed Limit ◽

Physical Quantities

We perform a comprehensive analysis of the set of parameters {ri} that provide the energy distribution of pure qutrits that evolve towards a distinguishable state at a finite time τ, when evolving under an arbitrary and time-independent Hamiltonian. The orthogonality condition is exactly solved, revealing a non-trivial interrelation between τ and the energy spectrum and allowing the classification of {ri} into families organized in a 2-simplex, δ2. Furthermore, the states determined by {ri} are likewise analyzed according to their quantum-speed limit. Namely, we construct a map that distinguishes those ris in δ2 correspondent to states whose orthogonality time is limited by the Mandelstam–Tamm bound from those restricted by the Margolus–Levitin one. Our results offer a complete characterization of the physical quantities that become relevant in both the preparation and study of the dynamics of three-level states evolving towards orthogonality.

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Molecular Classification and Tumor Microenvironment Characterization of Gallbladder Cancer by Comprehensive Genomic and Transcriptomic Analysis

Cancers ◽

10.3390/cancers13040733 ◽

2021 ◽

Vol 13 (4) ◽

pp. 733

Author(s):

Nobutaka Ebata ◽

Masashi Fujita ◽

Shota Sasagawa ◽

Kazuhiro Maejima ◽

Yuki Okawa ◽

...

Keyword(s):

Tumor Microenvironment ◽

Gallbladder Cancer ◽

Epithelial To Mesenchymal Transition ◽

Molecular Classification ◽

Mesenchymal Transition ◽

Elevated Expression ◽

Fresh Frozen ◽

Therapeutic Decision Making

Gallbladder cancer (GBC), a rare but lethal disease, is often diagnosed at advanced stages. So far, molecular characterization of GBC is insufficient, and a comprehensive molecular portrait is warranted to uncover new targets and classify GBC. We performed a transcriptome analysis of both coding and non-coding RNAs from 36 GBC fresh-frozen samples. The results were integrated with those of comprehensive mutation profiling based on whole-genome or exome sequencing. The clustering analysis of RNA-seq data facilitated the classification of GBCs into two subclasses, characterized by high or low expression levels of TME (tumor microenvironment) genes. A correlation was observed between gene expression and pathological immunostaining. TME-rich tumors showed significantly poor prognosis and higher recurrence rate than TME-poor tumors. TME-rich tumors showed overexpression of genes involved in epithelial-to-mesenchymal transition (EMT) and inflammation or immune suppression, which was validated by immunostaining. One non-coding RNA, miR125B1, exhibited elevated expression in stroma-rich tumors, and miR125B1 knockout in GBC cell lines decreased its invasion ability and altered the EMT pathway. Mutation profiles revealed TP53 (47%) as the most commonly mutated gene, followed by ELF3 (13%) and ARID1A (11%). Mutations of ARID1A, ERBB3, and the genes related to the TGF-β signaling pathway were enriched in TME-rich tumors. This comprehensive analysis demonstrated that TME, EMT, and TGF-β pathway alterations are the main drivers of GBC and provides a new classification of GBCs that may be useful for therapeutic decision-making.

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