Decrypting The Java Gene Pool: Predicting Objects' Lifetimes with Micro-patterns

Pretenuring long-lived and immortal objects into infrequently or never collected regions reduces garbage collection costs significantly. However, extant approaches either require computationally expensive, application-specific, off-line profiling, or consider only allocation sites common to all programs, i.e. invoked by the virtual machine rather than application programs. In contrast, we show how a simple program analysis, combined with an object lifetime knowledge bank, can be exploited to match both runtime system and application program structure with object lifetimes. The complexity of the analysis is linear in the size of the program, so need not be run ahead of time. We obtain performance gains between 6-77% in GC time against a generational copying collector for several SPEC jvm98 programs

Getting the measure of derivational morphology in adult speech a corpus analysis using MorphoQuantics

This paper describes the methodology used to compile a corpus called MorphoQuantics that contains a comprehensive set of 17,943 complex word types extracted from the spoken component of the British National Corpus (BNC). The categorisation of these complex words was derived primarily from the classification of Prefixes, Suffixes and Combining Forms proposed by Stein (2007). The MorphoQuantics corpus has been made available on a website of the same name; it lists 554 word-initial and 281 word-final morphemes in English, their etymology and meaning, and records the type and token frequencies of all the associated complex words containing these morphemes from the spoken element of the BNC, together with their Part of Speech. The results show that, although the number of word-initial affixes is nearly double that of word-final affixes, the relative number of each observed in the BNC is very similar; however, word-final affixes are more productive in that, on average, the frequency with which they attach to different bases is three times that of word-initial affixes. Finally, this paper considers how linguists, psycholinguists and psychologists may use MorphoQuantics to support their empirical work in first and second language acquisition, and clinical and educational research

Register variation in spoken British English: the case of verb-forming suffixation

The aim of this paper is to identify the effect of register variation on the occurrence of the four principal verb-forming suffixes in spoken English: -ate, -en, -ify and –ize, by building on the work of Biber et al. (1999), Plag et al. (1999) and Schmid (2011). Register variation effects were compared between the less formal Demographically-Sampled and the more formal Context-Governed components of the 1994 version of the British National Corpus. The pattern of -ize derivatives revealed the most marked register-based differences with respect to frequency counts and the creation of neologisms, whereas -en derivatives varied the least compared with the other three suffixes. Quantitative and qualitative analyses of these suffix profiles in the context of spoken language reveal markers of register formality that have not hitherto been explored; derivative usage patterns provide an additional dimension to previous research on register variation which has mainly focused on grammatical and lexical features of language

A diachronic corpus-based study into the effects of age and gender on the usage patterns of verb-forming suffixation in spoken British English

The aim of this paper is to ascertain the degree to which lexical diversity, density and creativity in everyday spoken British English have changed over a 20-year period, as a function of age and gender. Usage patterns of the four verb-forming suffixes, -ate, -en, -ify and -ize, were compared in contemporary speech from the BNC2014 with its 20-year old counterpart, the Demographically-Sampled (DS) component of the British National Corpus. Frequency comparisons revealed that verb suffixation is denser in the BNC2014 than in its earlier equivalent (DS), with the exception of the -en suffix, the use of which has decreased, particularly among females and younger speakers in general. Males and speakers in the 35-59 age range showed the greatest type diversity; there is evidence that this peak is occurring earlier in the more recent corpus. Contrary to expectations, females rather than males produced the largest number of neologisms and rare forms

A scrutinence of newies: corpus-based and experimental analyses of derivational word-formation in British English

This thesis is a comprehensive study of the mechanisms involved in the creation, recognition and understanding of new words in present-day British English formed by derivational suffixation. It is particularly interested in the formation of disposable words that are coined for a single use and thus do not gain official entries in dictionaries of English. An analysis of the use of the term “Productivity” and its attention in the literature revealed that it is inconsistent and in some cases incomplete; therefore a rationale was formed for a more comprehensive analysis through the examination of neologisms formed by suffixation. The research adopted two different but complementing methodologies to examine the Creativity of 145 suffixes in terms of the number of neologisms they create relative to their category size. Firstly, a corpus-based approach was taken, which considered twelve factors that could affect the number of neologisms a suffix creates; these included Derivative Factors of Prevalence, Opacity, Regularity, Convertibility and Distinguishability, and Base Factors of Stress Transfer, Sound Change, Truncation, Semantic Shift, Atypical PoS, Complexity and Allomorphic Variant. These factors were compared diachronically and across registers using databases formed from components of the original British National Corpus and the new Spoken BNC2014 (Love et al. 2017) to determine changes in the nature of Creativity over time and between contexts. It was concluded that two of the most influential factors on Creativity are the suffix’s frequency in the language (Prevalence), and the density of non-transparent members of its category (Opacity). Secondly, an experimental approach was taken to examine the ability of speakers to recognize and understand neologisms based on these factors through a Semantic Decision Task and Judgement Task, with reference to dual-route models of complex-word processing (Frauenfelder & Schreuder 1992; Schreuder & Baayen 1995) that predict faster processing times when the dual route is employed. To examine their ability to extract consistent meanings from neologisms, participants also participated in a follow-up study in which they were required to define neologisms. This study has shown that speakers generally have an extensive knowledge of suffixes and suffixation processes; the results of the Semantic Decision Task have provided support for theories of dual-route processing, where the employment of both direct and parsed routes increases the speed with which recognition and understanding can occur. The findings also have strong implications for the changing style of conversational speech towards patterns typical of more formal registers through suffixational Creativity; further study could examine present-day material of more formal registers to investigate whether these trends are one-way or if it is instead the case that register differences are becoming obscured by derivational Creativity and a move towards a common register for a wider variety of contexts

Software measurement for functional programming

This thesis presents an investigation into the usefulness of software measurement techniques, also known as software metrics, for software written in functional programming languages such as Haskell. Statistical analysis is performed on a selection of metrics for Haskell programs, some taken from the world of imperative languages. An attempt is made to assess the utility of various metrics in predicting likely places that bugs may occur in practice by correlating bug fixes with metric values within the change histories of a number of case study programs. This work also examines mechanisms for visualising the results of the metrics and shows some proof of concept implementations for Haskell programs, and notes the usefulness of such tools in other software engineering processes such as refactoring

An Imaging Fabry-Perot System for the Robert Stobie Spectrograph on the Southern African Large Telescope

We present the design of the Fabry-Perot system of the Robert Stobie Spectrograph on the 10-meter class Southern African Large Telescope and its characterization as measured in the laboratory. This system provides spectroscopic imaging at any desired wavelength spanning a bandpass 430 - 860 nm, at four different spectral resolving powers ranging from 300 to 9000. Our laboratory tests revealed a wavelength dependence of the etalon gap and parallelism with a maximum variation between 600 - 720 nm that arises because of the complex structure of the broadband multi-layer dielectric coatings. We also report an unanticipated optical effect of this multi-layer coating structure that produces a significant, and wavelength dependent, change in the apparent shape of the etalon plates. This change is caused by two effects: the physical non-uniformities or thickness variations in the coating layers, and the wavelength dependence of the phase change upon refection that can amplify these non-uniformities. We discuss the impact of these coating effects on the resolving power, finesse, and throughput of the system. This Fabry-Perot system will provide a powerful tool for imaging spectroscopy on one of the world's largest telescopes.Comment: 17 pages, 14 figures, accepted for publication in The Astronomical Journa

Impact Evaluation of a Central Australian Aboriginal Cultural Awareness Training Program for Health Professionals and Students

The aim of this study was to prospectively evaluate the impact of a Central Australian cultural awareness training program for health care staff. A mixed methods approach was used. Program participants completed a baseline and post-program questionnaire, which included an attitude scale assessing cultural safety, critical thinking and transformative unlearning, and open-ended questions. An online follow-up survey two months later repeated these questions. Mean scale scores were compared using paired and unpaired t-tests. Qualitative data were analysed thematically. Baseline scale mean was 45.7. At post-program it had statistically significantly increased to 47.3, using both the paired (p=\u3c 0.01) and unpaired t-test (p=\u3c 0.03). At the two-month follow-up it had decreased to 42.2. This was not statistically different from the baseline score with a paired (n=11) t-test (p=\u3c 0.37), however the difference was statistically significant with an unpaired t-test (p=\u3c 0.01) which included an additional eight respondents. Qualitative feedback was consistently positive. Many respondents learnt new information about the negative effects of colonisation on Aboriginal and/or Torres Strait Islander people, and how this continues to affect current health. Learning about Aboriginal and/or Torres Strait Islander cultures, kinship relationships and systems, and communication styles was identified as directly relevant to work practices. A cultural education program produced positive short-term changes in attitudes and was highly valued by participants. However, it is unclear if these changes are maintained in the medium term