Investigating the effects of corpus and configuration on assistive input methods

<p>Assistive technologies aim to provide assistance to those who are unable to perform various tasks in their day-to-day lives without tremendous difficulty. This includes — amongst other things — communicating with others. Augmentative and adaptive communication (AAC) is a branch of assistive technologies which aims to make communicating easier for people with disabilities which would otherwise prevent them from communicating efficiently (or, in some cases, at all). The input rate of these communication aids, however, is often constrained by the limited number of inputs found on the devices and the speed at which the user can toggle these inputs. A similar restriction is also often found on smaller devices such as mobile phones: these devices also often require the user to input text with a smaller input set, which often results in slower typing speeds. Several technologies exist with the purpose of improving the text input rates of these devices. These technologies include ambiguous keyboards, which allow users to input text using a single keypress for each character and trying to predict the desired word; word prediction systems, which attempt to predict the word the user is attempting to input before he or she has completed it; and word auto-completion systems, which complete the entry of predicted words before all the corresponding inputs have been pressed. This thesis discusses the design and implementation of a system incorporating the three aforementioned assistive input methods, and presents several questions regarding the nature of these technologies. The designed system is found to outperform a standard computer keyboard in many situations, which is a vast improvement over many other AAC technologies. A set of experiments was designed and performed to answer the proposed questions, and the results of the experiments determine that the corpus used to train the system — along with other tuning parameters — have a great impact on the performance of the system. Finally, the thesis also discusses the impact that corpus size has on the memory usage and response time of the system.</p>

Investigating the effects of corpus and configuration on assistive input methods

<p>Assistive technologies aim to provide assistance to those who are unable to perform various tasks in their day-to-day lives without tremendous difficulty. This includes — amongst other things — communicating with others. Augmentative and adaptive communication (AAC) is a branch of assistive technologies which aims to make communicating easier for people with disabilities which would otherwise prevent them from communicating efficiently (or, in some cases, at all). The input rate of these communication aids, however, is often constrained by the limited number of inputs found on the devices and the speed at which the user can toggle these inputs. A similar restriction is also often found on smaller devices such as mobile phones: these devices also often require the user to input text with a smaller input set, which often results in slower typing speeds. Several technologies exist with the purpose of improving the text input rates of these devices. These technologies include ambiguous keyboards, which allow users to input text using a single keypress for each character and trying to predict the desired word; word prediction systems, which attempt to predict the word the user is attempting to input before he or she has completed it; and word auto-completion systems, which complete the entry of predicted words before all the corresponding inputs have been pressed. This thesis discusses the design and implementation of a system incorporating the three aforementioned assistive input methods, and presents several questions regarding the nature of these technologies. The designed system is found to outperform a standard computer keyboard in many situations, which is a vast improvement over many other AAC technologies. A set of experiments was designed and performed to answer the proposed questions, and the results of the experiments determine that the corpus used to train the system — along with other tuning parameters — have a great impact on the performance of the system. Finally, the thesis also discusses the impact that corpus size has on the memory usage and response time of the system.</p>

Structure and instability of the ionization fronts around moving black holes

ABSTRACT In this paper, we focus on understanding the physical processes that lead to stable or unstable ionization fronts (I-fronts) observed in simulations of moving black holes (BHs). The front instability may trigger bursts of gas accretion, rendering the BH significantly more luminous than at steady state. We perform a series of idealized three-dimensional radiation hydrodynamics simulations resolving the I-fronts around BHs of mass MBH and velocity $v$∞ accreting from a medium of density nH. The I-front, with radius RI, transitions from D-type to R-type as the BH velocity becomes larger than a critical value $v_\mathrm{R}\sim 40\, \mathrm{km\,s}^{-1}$. The D-type front is preceded by a bow-shock of thickness ΔRI that decreases as $v$∞ approaches $v$R. We find that both D-type and R-type fronts can be unstable given the following two conditions: (i) for D-type fronts the shell thickness must be ΔRI/RI &lt; 0.05 (i.e. $v_\infty \gtrsim 20\, \mathrm{km\,s}^{ -1}$), while no similar restriction holds for R-type fronts; (ii) the temperature jump across the I-front must be TII/TI &gt; 3. This second condition is satisfied if $T_\mathrm{I}\lt 5000\, \mathrm{K}$ or if $n_\mathrm{H}\, M_\mathrm{BH} \gtrsim 10^6\, M_\odot \, \mathrm{cm^{-3}}$. Due to X-ray pre-heating typically $T_\mathrm{I} \sim 10^4\, \mathrm{K}$, unless the D-type shell is optically thick to X-rays, which also happens when $n_\mathrm{H}\, M_\mathrm{BH}$ is greater than a metallicity-dependent critical value. We thus conclude that I-fronts around BHs are unstable only for relatively massive BHs moving trough very dense molecular clouds. We briefly discuss the observational consequences of the X-ray luminosity bursts likely associated with this instability.

Why were adult women excluded from the Olympic Games? = ¿Por qué las mujeres adultas estaban excluidas de los Juegos Olímpicos?

It is a well-known fact that adult women were banned from attending the Olympic Games and that those who violated this rule were supposed to be executed. It is generally assumed and indeed very likely that the exclusion can be seen as a remnant of an age-old religious taboo with a terrifying and deterring effect. In ancient Greece, it is only the cult of Ephesian Artemis in which a similar restriction is applied to women, but similar rules are found all over the world and concern hunters and their wives. In addition, written sources attest that the vicinity of the sanctuary was regarded as a superb hunting ground and Early Iron Age finds also suggest that initially, hunting was the main attraction of the sanctuary. It is therefore argued that the exclusion of married women at Olympia derived from hunting ceremonies and from the related cult of Artemis.Resumen: Es un hecho bien conocido que las mujeres adultas estaban excluidas de poder asistir a los Juegos Olímpicos y que aquéllas que violasen esta regla supuestamente serían ejecutadas. Se asume generalmente y es sin duda muy probable que la exclusión pueda ser vista como un remanente de un tabú religioso secular con un efecto de aterrorizar y disuadir. En la antigua Grecia, solamente en el culto de Artemisa Efesia se aplicaba una restricción similar a las mujeres, pero se encuentran reglas similares por todo el mundo y conciernen a los cazadores a sus mujeres. Además, las fuentes escritas dan fe de que la cercanía del santuario se veía como un campo de caza soberbio, y los hallazgos de la Edad de Hierro temprana también sugieren que inicialmente, la caza era la principal atracción del santuario. Se argumenta, así pues, que la exclusión de las mujeres casadas en Olimpia derivaba de las ceremonias de caza y del culto relacionado de Artemisa.Key words: Women, banning, Olympic Games, religion, rules.Palabras clave: Mujeres, prohibición, Juegos Olímpicos, religión, reglas.

A Dispersion-Theoretic Account of Taiwanese CV phonotactics

In Taiwanese, oral voice consonants and nasal stops are in complementary distribution in the onset position: oral voiced consonants only precede phonemically oral vowels, and nasal stops only precede nasal vowels. Similar restriction in the distribution of these segments is not found in other languages with phonemic nasal vowels, such as French and Portuguese. Following studies showing that Taiwanese nasal vowels are fully nasalized, while French and Portuguese ones have delay in nasality (Chang et al., 2011; Delvaux et al., 2008; Parkinson, 1983), this study proposes a Dispersion-Theoretic account to connect phonetic observation about vocalic nasality to the phonotactic restrictions on voicing and nasality. Using a three-stage analysis (Flemming 2006, 2008), where Phonetic Realization is a distinct component of the grammar, the analysis is show how a cross-linguistic different in phonetic implementation of nasality is able to derive differences in surface phonotactics. The analysis also makes explicitly testable predictions about the perception and the typology of the distributions of voiced and nasal segments.

4 Temporal Jurisdiction over Acts before the Period of Limitation

Regardless of the date of entry into force of the obligation allegedly breached, or of the acceptance of its jurisdiction, a tribunal might not hear a claim if it was brought too long after the challenged act, commonly referred to as a ‘time limit’ or ‘time bar’ on a claim, or an application of a ‘statute of limitations’. This chapter addresses the effect of treaty provisions that prevent a tribunal from hearing delayed claims. It addresses the effect of all such provisions, even though some affect the admissibility of a claim rather than the tribunal’s jurisdiction. The chapter then examines whether, in the absence of a treaty provision that limits a tribunal’s ability to hear a delayed claim, general principles of law impose a similar restriction.

Regulation of genetic flux between bacteria by restriction–modification systems

Restriction–modification (R-M) systems are often regarded as bacteria's innate immune systems, protecting cells from infection by mobile genetic elements (MGEs). Their diversification has been recently associated with the emergence of particularly virulent lineages. However, we have previously found more R-M systems in genomes carrying more MGEs. Furthermore, it has been suggested that R-M systems might favor genetic transfer by producing recombinogenic double-stranded DNA ends. To test whether R-M systems favor or disfavor genetic exchanges, we analyzed their frequency with respect to the inferred events of homologous recombination and horizontal gene transfer within 79 bacterial species. Genetic exchanges were more frequent in bacteria with larger genomes and in those encoding more R-M systems. We created a recognition target motif predictor for Type II R-M systems that identifies genomes encoding systems with similar restriction sites. We found more genetic exchanges between these genomes, independently of their evolutionary distance. Our results reconcile previous studies by showing that R-M systems are more abundant in promiscuous species, wherein they establish preferential paths of genetic exchange within and between lineages with cognate R-M systems. Because the repertoire and/or specificity of R-M systems in bacterial lineages vary quickly, the preferential fluxes of genetic transfer within species are expected to constantly change, producing time-dependent networks of gene transfer.

Deforming of Elastic-Plastic Medium with Self-Similar Restriction

The problem of shock deforming of elastic-plastic half-space with large deformation was examined. We have obtained that the deformation state can be changed in two types of simple plastic waves and two types of shock elastic waves in the case of self-similar medium motion. The speeds and characteristics of plastic waves were examined. The numerical solution of boundary value problem was found.

A note on the nonperturbative nature of the Schwinger effect in the expanding de Sitter space

We reconsider a recent perturbative calculation [M. A. Băloi, Mod. Phys. Lett. A29, 1450138 (2014)] of particle production in the expanding de Sitter space in an external electromagnetic field and apply it to the case of a constant uniform electric field in two dimensions. We show that perturbative number of created particles significantly differs from the existing nonperturbative result based on the Bogoliubov transformation method. We also point out that for a physically meaningful perturbative amplitude one should restrict to external potentials Aμ which in conformal coordinates vanish at infinite times. Potentials which do not respect this condition lead to gauge-dependent amplitudes, which also show close similarities with amplitudes in flat space in the unphysical case when the external potential suddenly vanishes. These problems are intimately linked with the finite upper limit of the conformal time in the de Sitter space and most probably a similar restriction should be imposed in perturbative calculations in FRW spacetimes with the same property.