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Applying a uniform marked morphism to a word

Anna Frid
1999 Discrete Mathematics & Theoretical Computer Science  
The functions described include the subword complexity, frequency of factors, and the recurrence function.  ...  The relations obtained for the image of a word can be used also for the image of a factorial language.  ...  Acknowledgements I am grateful to the anonymous referee who mentioned flaws in what is now Theorems 4 and 6, and showed the way to correct them.  ... 
doi:10.46298/dmtcs.255 fatcat:fncheuarxjas7gfykkbc32kxxa

Effective S-adic Symbolic Dynamical Systems [chapter]

Valérie Berthé, Thomas Fernique, Mathieu Sablik
2016 Lecture Notes in Computer Science  
We focus in this survey on effectiveness issues for S-adic subshifts and tilings.  ...  An S-adic subshift or tiling space is a dynamical system obtained by iterating an infinite composition of substitutions, where a substitution is a rule that replaces a letter by a word (that might be multi-dimensional  ...  Some Decisions Problems for Substitutions In the one-dimensional case, numerous decidability results exist for fixed points of substitutions (D0L words), and their images by general morphisms (HD0L words  ... 
doi:10.1007/978-3-319-40189-8_2 fatcat:7nnzcfbuonalfdepcumhtmor7u

The Pagoda Sequence: a Ramble through Linear Complexity, Number Walls, D0L Sequences, Finite State Automata, and Aperiodic Tilings

Fred Lunnon
2009 Electronic Proceedings in Theoretical Computer Science  
A remarkable ternary analogue of the Thue-Morse sequence is introduced having deficiency 2 modulo 3, and this property verified via the re-interpretation of the number wall as an aperiodic plane tiling  ...  and context-free Lindenmayer (D0L) sequences.  ...  Recall that a sequence of symbols is square-free when no factor word (of consecutive symbols) is followed immediately by a copy of itself; similarly, a sequence may be cube-free, power-free.  ... 
doi:10.4204/eptcs.1.13 fatcat:dz75pbu47jhmde6afduvn4pdyu

Harmonizations of Time with Non Periodic Ordered Structures in Discrete Geometry and Astronomy [chapter]

Juan García Escudero
2005 Lecture Notes in Computer Science  
Non periodic ordered tilings can be used for the generation of discrete structures in the time and frequency domains.  ...  The pulsation of some semiregular and delta scuti stars is reflected in their light curves which can be modelled by means of sinusoidal sequences related with the golden number. ...Comment le monde doit  ...  The language consists in the words a, abaa, abaaaababaaabaa, ...  ... 
doi:10.1007/978-3-540-31807-1_8 fatcat:j3apf55ljrduxkllbl5425dg7m

Subword complexity of uniform D0L words over finite groups

Ilya Goldstein
2011 Theoretical Computer Science  
We deal with the subword complexity of uniform D0L words obtained from group substitutions. Our main interest is whether the subword complexity is "almost proportional" to the length of the factor.  ...  The factors of a D0L word were studied, for instance, by Frid [12] , who considered also the frequency of these factors.  ...  The subword complexity of D0L words was studied by Cassaigne [2] , who also considered the number of so-called special and bi-special factors.  ... 
doi:10.1016/j.tcs.2011.06.019 fatcat:6rb2vizd2vc5tge3rsgcst5aea

Incorporating Knowledge of Secondary Structures in a L-System-Based Encoding for Protein Folding [chapter]

Gabriela Ochoa, Gabi Escuela, Natalio Krasnogor
2006 Lecture Notes in Computer Science  
A peptide bond is a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water.  ...  It appears that the occurrence of motifs and sub-structures is an important component in protein folding, and these sub-structures may be captured by a grammar-based encoding.  ...  Acknowledgements Natalio Krasnogor acknowledges EPSRC (GR/T07534/01, EP/D021847/1) and BBSRC (BB/C511764/1) for funding his research on protein structure prediction, comparison and self-assembly  ... 
doi:10.1007/11740698_22 fatcat:mckmpz3xavhdbicsuaiqnrajpi

Factor frequencies in generalized Thue-Morse words [article]

Lubomira Balkova
2011 arXiv   pre-print
Frid, On the frequency of factors in a D0L word, Journal of Automata, Languages and Combinatorics 3 (1998), 29-41 and the study of generalized Thue-Morse words by S.  ...  We describe factor frequencies of the generalized Thue-Morse word t_b,m defined for integers b greater than 1, m greater than 0 as the fixed point starting in 0 of the morphism ϕ_b,m given by ϕ_b,m(k)=  ...  Upper bound on frequencies In the last section, let us show and explain that the optimal upper bound on the number of factor frequencies in infinite words whose language is invariant under more symmetries  ... 
arXiv:1107.5033v1 fatcat:t2qyztnu5zayvg635zkem4benm

Asymptotic subword complexity of fixed points of group substitutions

Ilya Goldstein
2009 Theoretical Computer Science  
The subword complexity of fixed points of some types of substitutions was studied by various authors.  ...  Here we introduce a family of substitutions, arising from multiplication tables of finite groups and other similar structures, and analyze their subword complexity.  ...  Allouche and to two anonymous referees for their very extensive comments on the first draft of the paper.  ... 
doi:10.1016/j.tcs.2009.01.025 fatcat:c7pkljnrfbarbh5xdrwgh3567m

Grammatical Evolution with Restarts for Fast Fractal Generation [article]

Manuel Cebrian, Manuel Alfonseca, Alfonso Ortega
2010 arXiv   pre-print
These strategies exploit the fact that the probability of finding a solution in short executions is non-negligible and yield a severe reduction, both in the expected execution time (up to one order of  ...  In a previous work, the authors proposed a Grammatical Evolution algorithm to automatically generate Lindenmayer Systems which represent fractal curves with a pre-determined fractal dimension.  ...  Acknowledgements This work has been sponsored by the Spanish Ministry of Education and Science (MEC), project number TSI2005-08225-C07-06.  ... 
arXiv:0805.1696v2 fatcat:oqz2uh65wne5xnpb3rc3qbfbr4

Naming in semantic dementia—what matters?

Matthew A.Lambon Ralph, Kim S. Graham, Andrew W. Ellis, John R. Hodges
1998 Neuropsychologia  
sectional study of the factors a}ecting picture naming in semantic dementia based on data obtained from eight patients\ together with a longitudinal analysis of naming in another patient[ Various properties  ...  One of the major symptoms of semantic dementia "or progressive~uent aphasia# is profound word!_nding di.culties[ We present here a cross!  ...  Acknowled`ements*We are indebted to the continuing support of the patients included in this paper and also Jim Becker\ Kellie Doyle and Steve DeKoskey "University of Pittsburgh# for allowing us to report  ... 
doi:10.1016/s0028-3932(97)00169-3 pmid:9751441 fatcat:ujn66tkprvhx7fg4ey3wegb4zq

Are recognition deficits following occipital lobe TMS explained by raised detection thresholds?

Thomas Kammer, Hans-günther Nusseck
1998 Neuropsychologia  
as a change in visual contrast threshold[ Four subjects detected the orientation of an U!  ...  noise ratio of the visual stimuli by TMS\ which can be compensated for by increasing the contrast of the stimuli[ Þ 0887 Elsevier Science Ltd[ All rights reserved[ Key Words] transcranial magnetic stimulation  ...  thank Lucia Lehr and Reinhard Feiler for technical support\ Claudia Holt for graphic design and Karl Gegenfurtner for comments on the manuscript[  ... 
doi:10.1016/s0028-3932(98)00003-7 pmid:9842761 fatcat:c34cgrwxlbcd3boo5uysa74ubm

Visual Models of Plant Development [chapter]

Przemyslaw Prusinkiewicz, Mark Hammel, Jim Hanan, Radomír Měch
1997 Handbook of Formal Languages  
In these notes we s u r v ey applications of L-systems to the modeling of plants, with an emphasis on the results obtained since the comprehensive presentation of this area in The Algorithmic Beauty of  ...  enhance the use of L-systems as a language for describing developmental algorithms and as input for simulation programs, and { new biological applications of L-systems.  ...  Dale Brisinda implemented the L-system model of acrotonic structures discussed in Section 4.2.4.  ... 
doi:10.1007/978-3-642-59126-6_9 fatcat:o2iusyna4va7tc7xddgcbvtpje


2004 Current Trends in Theoretical Computer Science  
Cassaigne, A. Lepistö, G. Richomme, P. Séébold and J. Shallit for their careful reading of parts of a preliminary version of the paper. In addition the authors are grateful to A.  ...  Lepistö for his help to complete the presentation. We are also grateful to D.E. Knuth for his advices and bibliographic comments.  ...  means that all words appear as factors, and that all factors of length n appear with the same frequency 1/b n .  ... 
doi:10.1142/9789812562494_0059 fatcat:rb3muz6tsffbrpm26j4aj2rkey

Creating false memories for visual scenes

Michael B. Miller, Michael S. Gazzaniga
1998 Neuropsychologia  
paradigm reintroduced by Roediger and McDermott ð07Ł[ The word paradigm has been useful in creating false memories in several neuroimaging studies ð02\ 10Ł because of the high frequency of false recognition  ...  the exemplars from the scene were removed "e[g[ a beach ball# and used as lures during an auditory recognition test[ Subjects| performance on this paradigm was compared with their performance on the word  ...  bene_t in averaging data across many trials and in making more direct comparisons between types of items and baseline conditions[ Two\ the words used as lures have a di}erent word frequency and imageability  ... 
doi:10.1016/s0028-3932(97)00148-6 pmid:9705061 fatcat:w6gzxlxsbjbtddlh3ophanjnry

Fractal and Polar Microstrip Antennas and Arrays for Wireless Communications [chapter]

Paulo Fernandes da Silva Junior, Mauro Sérgio Pinto Silva Filho, Ewaldo Eder de Carvalho Santana, Paulo Henrique da Fonseca Silva, Elder Eldervitch Carneiro de Oliveira, Maciel Alves de Oliveira, Fabrício Ferreira Batista, Alexandre Jean René Serres, Raimundo Carlos Silvério Freire, Almir Souza, Silva Neto, Severino Aires de Araújo Neto (+1 others)
2019 Wireless Mesh Networks - Security, Architectures and Protocols [Working Title]  
This chapter presents the research done by authors in recent years on microstrip antennas and their applications in wireless sensors network.  ...  Experimental characterization of antennas and dielectric materials has been performed with the use of a vector network analyzer.  ...  Formal definitions of D0L-systems and their operation can be found in [29, 32] .  ... 
doi:10.5772/intechopen.83401 fatcat:yao2so4zkjfupaxfwedgjnoagm
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