Search results for "Alphabet"
showing 10 items of 68 documents
On the product of balanced sequences
2011
The product w = u ⊗ v of two sequences u and v is a naturally defined sequence on the alphabet of pairs of symbols. Here, we study when the product w of two balanced sequences u,v is balanced too. In the case u and v are binary sequences, we prove, as a main result, that, if such a product w is balanced and deg ( w ) = 4, then w is an ultimately periodic sequence of a very special form. The case of arbitrary alphabets is approached in the last section. The partial results obtained and the problems proposed show the interest of the notion of product in the study of balanced sequences.
Lightweight BWT Construction for Very Large String Collections
2011
A modern DNA sequencing machine can generate a billion or more sequence fragments in a matter of days. The many uses of the BWT in compression and indexing are well known, but the computational demands of creating the BWT of datasets this large have prevented its applications from being widely explored in this context. We address this obstacle by presenting two algorithms capable of computing the BWT of very large string collections. The algorithms are lightweight in that the first needs O(m log m) bits of memory to process m strings and the memory requirements of the second are constant with respect to m. We evaluate our algorithms on collections of up to 1 billion strings and compare thei…
Lightweight algorithms for constructing and inverting the BWT of string collections
2013
Recent progress in the field of \{DNA\} sequencing motivates us to consider the problem of computing the Burrows‚ÄìWheeler transform (BWT) of a collection of strings. A human genome sequencing experiment might yield a billion or more sequences, each 100 characters in length. Such a dataset can now be generated in just a few days on a single sequencing machine. Many algorithms and data structures for compression and indexing of text have the \{BWT\} at their heart, and it would be of great interest to explore their applications to sequence collections such as these. However, computing the \{BWT\} for 100 billion characters or more of data remains a computational challenge. In this work we ad…
Reducing Local Alphabet Size in Recognizable Picture Languages
2021
A recognizable picture language is defined as the projection of a local picture language defined by a set of two-by-two tiles, i.e. by a strictly-locally-testable (SLT) language of order 2. The family of recognizable picture languages is also defined, using larger k by k tiles, \(k>2\), by the projection of the corresponding SLT language. A basic measure of the descriptive complexity of a picture language is given by the size of the SLT alphabet using two-by-two tiles, more precisely by the so-called alphabetic ratio of sizes: SLT-alphabet/picture-alphabet. We study how the alphabetic ratio changes moving from two to larger tile sizes, and we obtain the following result: any recognizable pi…
Luciano Perondi. 字母设计的攀登者 / Luciano Perondi. The Grimpeur of Alphabets
2010
平面设计涉及广泛，其中字体设计是一项耗时而细 致的工作，但是在意大利由于没有一个特殊的印 刷文化背景，不论在专业上还是经济上，字体设计 都没有得到适当的认可，并常常会被忽视。然而， 在我们国家，这是拉丁字符的摇篮，在世界印刷史 上，有一些堪称里程碑标志的伟大人物。其中， 15世纪Francesco Griffo设计了一种当时平装书使 用的字体，到了18世纪Giovan Battista Bodoni认 为这种字体得到了最广泛的认可，其以严谨和谐的 几何比例为特点。 今天有很多（而且往往不为人所知）英国设计师在 一个不稳定的社会经济背景下工作。因为，除了 已前面提到的文化缺陷外，设计师并没有得到足够 的重视。从专业受欢迎度来说，排版设计无论是专 业的严谨性、可塑性、还是天赋直觉都不比其他的 专业逊色。Luciano Perondi尽管年轻，但是在为 报纸、出版物、标志和视觉识别系统进行字符设计 方面具有重要的经验。在理论研究领域，他创办了 EXP团体，成员涉及心理学家、传播理论家、设计 师、符号学家、平面设计师和语言学家，对写作和 阅读等相关主题进行研究。 In the extensive field of graphic design there are specialized areas, such as the type design, which require a long, careful and meticulous work, not always recognized and appreciated in an appropriate way both eco…
La città di Alphabet. Architettura per prosumers.
2021
Attraverso alcuni aspetti salienti dell’ideazione, della produzione e dell’opposizione al progetto del Toronto Quayside di Sidewalk labs, l’articolo discute l’influenza delle infrastrutture digitali per l’informazione sul progetto della casa e del quartiere. L’ampliamento delle attività svolte da remoto nello spazio domestico, enfatizzato dal quotidiano della pandemia da Covid 19, costituisce per gli oligopolisti planetari degli urban data come Alphabet un utile volano pubblicitario e un acceleratore. La fusione dei nuovi vessilli della tecnoemancipazione e della sostenibilità in ipotesi sperimentali che mirano a costruirsi sia per intero che per parti realizza un nuovo orizzonte in cui lo …
Noi che siamo passati dalla Libia. Giovani in viaggio fra alfabeti e multilinguismo
2021
This book is part of a broader study into new migration experiences and, in particular, that of young migrants who have recently arrived in Italy via the Mediterranean route. The main object under investigation is the linguistic and communicative resources available to these migrants at their point of departure and how these have been used and modified during their journey.
L’importanza dei prerequisiti e dello screening precoce nella scuola dell’infanzia
2016
Questo contributo si propone di sottolineare l’importanza di alcune competenze cognitive, detti prerequisiti, che sono implicate nell’acquisizione delle abilità di lettura e scrittura come ad esempio: la conoscenza dell’alfabeto; la consapevolezza fonologica; la denominazione rapida automatica (RAN); la memoria fonologica e la processazione visiva. Numerose ricerche, anche internazionali, mostrano l’importanza dell’esercizio di tali abilità all’interno della scuola dell’infanzia anche ai fini della prevenzione dello sviluppo di difficoltà di apprendimento e/o di veri e propri disturbi nella successiva carriera accademica del bambino. Inoltre, la realizzazione di interventi didattici mirati …
Tally languages accepted by Monte Carlo pushdown automata
1997
Rather often difficult (and sometimes even undecidable) problems become easily decidable for tally languages, i.e. for languages in a single-letter alphabet. For instance, the class of languages recognizable by 1-way nondeterministic pushdown automata equals the class of the context-free languages, but the class of the tally languages recognizable by 1-way nondeterministic pushdown automata, contains only regular languages [LP81]. We prove that languages over one-letter alphabet accepted by randomized one-way 1-tape Monte Carlo pushdown automata are regular. However Monte Carlo pushdown automata can be much more concise than deterministic 1-way finite state automata.
Hyvän lapsen ja kasvattamisen ideaalit – tutkimus aapisten ja lukukirjojen moraalisen kosmologian muutoksista itsenäisyyden aikana
2001
Tässä tutkimuksessa käsitellään suomenkielisten aapisten ja lukukirjojen sisältämien opetuskertomusten moraalisia ideaaleja ja niiden muutoksia itsenäisyyden aikana. Minkälaisen maailman ihanne kirjoissa luodaan ja mihin kiinnitetään ajatus, että jokin toiminta tai ajattelu on oikeaa, hyvää ja suotavaa, toinen väärää, pahaa ja torjuttavaa? Aineistona tutkimuksessa on käytetty 57 aapista ja lukukirjaa. Aineisto on analysoitu yhteisöllisen moraalin kosmologisia ominaisuuksia koskevien sosiologisten teorioiden ajatuksin. Mary Douglas käsittelee moraalista kosmologiaa symbolisina järjestyksinä, jotka sisältävät maailman ja ihmisen olemista koskevia, itsestään selvinä pidettyjä oletuksia. Keskei…