Low-Power Boards Enabling ML-Based Approaches to FDIR in Space-Based Applications

Modern satellite complexity is increasing, thus requiring bespoke and expensive on-board solutions to provide a Failure Detection, Isolation and Recovery (FDIR) function. Although FDIR is vital in ensuring the safety, autonomy, and availability of satellite systems in flight, there is a clear need in the space industry for a more adaptable, scalable, and cost-effective solution. This paper explores the current state of the art for Machine Learning error detection and prognostic algorithms utilized by both the space sector and the commercial sector. Although work has previously been done in the commercial sector on error detection and prognostics, most commercial applications are not nearly as limited by the power, mass, and radiation tolerance constraints as for operation in a space environment. Therefore, this paper also discusses several Commercial Off-The-Shelf (COTS) multi-core micro-processors, small-footprint boards that will be explored as possible testbeds for future integration into a satellite in-orbit demonstrator

Developing Machine Learning Models for Space Based Edge AI Platforms

On September 3rd 2020, one of the first small satellites equipped with Edge AI hardware was launched. The inclusion of a UB0100 board on PhiSat-1 enabled the use of deep neural networks to provide real-time image analysis on-board an Earth Observation satellite. The primary benefit of this was a 90% reduction in downlink data as the system only transmitted non-cloudy, and thus usable, data. PhiSat-1 and missions like it have started the revolution of satellite-based machine learning, leading ESA and other space agencies to further explore the in-situ deployment of machine-learning models. Other applications that can benefit from on-board space-based machine learning capabilities range from anomaly detection and prognostics to feature recognition and object detection. This paper focuses on the application of anomaly detection models on space-ready Edge AI hardware to detect and classify anomalous behaviour in telemetry data. The ability to accurately detect anomalies onboard satellite systems has the potential to both increase system lifetimes and reduce satellite operator workloads. The limitations of Edge AI boards and the space environment put restrictions on the models that can be used. Limited power and potential single event upsets constrain the complexity of the models that can be deployed. Therefore, this paper is targeted at models that will run efficiently within these constraints. We describe an experiment that evaluates the suitability of different anomaly detection approaches (multi-layer-perceptrons, auto-encoders, etc.) for space applications. These approaches are compared both in terms of their performance in the anomaly detection tasks and how well they run on “space ready” low-power hardware. We focus on the Intel Myriad chipset, the basis of the UB0100, which hosted the machine learning image analysis model on PhiSat-1. Our evaluations use both the MIMII machine audio dataset, a well-regarded anomaly detection dataset that is a good proxy for telemetry data, and a dataset generated using anonymized NASA mission telemetry data. The findings show how well basic models work when presented with anomalous satellite telemetry

Search for domain wall dark matter with atomic clocks on board global positioning system satellites

Cosmological observations indicate that 85% of all matter in the Universe is dark matter (DM), yet its microscopic composition remains a mystery. One hypothesis is that DM arises from ultralight quantum fields that form macroscopic objects such as topological defects. Here we use GPS as a ~ 50,000 km aperture DM detector to search for such defects in the form of domain walls. GPS navigation relies on precision timing signals furnished by atomic clocks hosted on board GPS satellites. As the Earth moves through the galactic DM halo, interactions with topological defects could cause atomic clock glitches that propagate through the GPS satellite constellation at galactic velocities ~ 300 km/s. Mining 16 years of archival GPS data, we find no evidence for DM in the form of domain walls at our current sensitivity level. This allows us to improve the limits on certain quadratic scalar couplings of domain wall DM to standard model particles by several orders of magnitude.Comment: 7 pages (main text), and 12 pages for Supplementary Information. v3: Update titl

Road traffic noise and cognitive function in older adults : a cross-sectional investigation of The Irish Longitudinal Study on Ageing

This research is funded under the Environmental Protection Agency (EPA) Research Programme 2014–2020.Background The World Health Organization published updated Environmental Noise Guidelines in 2018. Included are recommended limit values for environmental noise exposure based on systematic reviews for a range of health outcomes, including cognitive impairment. There is emerging evidence in the literature that chronic exposure to road traffic noise may affect cognitive function in older adults, but this relationship is not well established. This study spatially linked nationally representative health microdata from The Irish Longitudinal Study on Ageing to building-level modelled noise data for two cities in the Republic of Ireland. This was used to investigate associations between exposure to road traffic noise and cognitive function in a sample of older adults, independent of a range of socio-demographic and behavioural characteristics, as well as exposure to air pollution. Methods We used the Predictor-LimA Advanced V2019.02 software package to estimate noise originating from road traffic for the cities of Dublin and Cork in Ireland according to the new common noise assessment methodology for the European Union (CNOSSOS-EU). Noise exposure values were calculated for each building and spatially linked with geo-coded TILDA microdata for 1706 individuals aged 54 and over in the two cities. Ordinary least squares linear regression models were estimated for eight standardised cognitive tests including noise exposure as an independent variable, with standard errors clustered at the household level. Models were adjusted for individual sociodemographic, behavioural and environmental characteristics. Results We find some evidence that road traffic noise exposure is negatively associated with executive function, as measured by the Animal Naming Test, among our sample of older adults. This association appears to be accounted for by exposure to air pollution when focusing on a sub-sample. We do not find evidence of an association between noise exposure and memory or processing speed. Conclusions Long term exposure to road traffic noise may be negatively associated with executive function among older adults.Publisher PDFPeer reviewe

Road traffic noise, quality of life, and mental distress among older adults : evidence from Ireland

Funding for this research was provided by the Irish Environmental Protection Agency (EPA) Research Programme 2014–2020, which is funded by the Department of Environment, Climate and Communications in Ireland.This research contributes to an emerging evidence base that considers a possible relationship between exposure to road traffic noise and mental distress. This study aimed to determine whether chronic exposure to road traffic noise was associated with quality of life or various measures of mental distress. We spatially linked high-quality modelled noise exposure data for the cities of Dublin and Cork in Ireland to The Irish Longitudinal Study on Ageing, allowing an examination of these health outcomes among older adults while adjusting for socio-demographic and behavioural characteristics. Exposure to air pollution was also considered in the analysis, allowing any associations between noise and either quality of life or mental distress that were independent of this other stressor to be isolated. While the study did not detect evidence of an association between noise exposure and depression, anxiety, stress, or worry, it identified a negative association between exposure to road traffic noise and quality of life that was independent of a range of socio-demographic and behavioural factors. Moving from the highest quintile of noise exposure to the lowest was associated with an increase on the CASP-12 quality of life scale of 1.08 of a standard deviation.Publisher PDFPeer reviewe

An drámaíocht aistrithe faoin spotsolas

In this article, the authors attempt to highlight the craft of translation within the field of Irish-language drama as its own distinct discipline. The fields of both Irish-language drama and Hiberno-English drama, are considered to be fairly new but both movements, in their nascent years, had to draw on international literature in order to add to the dramatic repertoire in Ireland over the past century. Translation was seen to be one of the most effective tools in this attempt, especially in the case of Irish-language drama. However, rarely – if ever - have Irish-language translations from across the 20th century been catagorised or compared to their international counterparts within the realm of drama critique. This article demonstrates that such catagorisation and comparison can be carried out on translated Irish-language drama through an international lens. The article engages with topics such as using drama as a mirror to societal values and norms, intercultural exchange, closet drama as a genre, the concepts of speakability and performability, as well as foreignization strategies used in translation. Furthermore, the article explores the role of the translator within the translation process as well as the different types of translation i.e. full translation, calque or adaptation. The aim of this article is not to be an exhaustive guide, but to cast the research net wider than has previously been done to encompass a more inclusive context and model for translated Irish-language drama. San alt seo, déanann na húdair iarracht aird a tharraingt ar cheird an aistriúcháin i réimse na drámaíochta Gaeilge mar dhisciplín ar leith. Is réimse sách nua é drámaíocht na Gaeilge agus Bhéarla na hÉireann trí chéile in Éirinn ach b’éigean don dá ghluaiseacht sin tarraingt as litríocht an domhain mhóir chun cur le repertoire na drámaíochta. Ceann de na bealaí is mó a bhí in armlón an dá ghluaiseacht sin ba ea aghaidh a thabhairt ar an aistriúchán chun borradh a chur faoin réimse, go háirithe drámaíocht na Gaeilge. Ní minic a dhéantar na haistriúcháin sa réimse seo a chatagóiriú ná a chur i gcomparáid le heiseamláirí idirnáisiúnta eile ach i bhfianaise ábhar an ailt seo, is léir gur féidir tabhairt faoi iniúchadh ar dhrámaíocht aistrithe na Gaeilge trí lionsa idirnáisiúnta. I measc na ngnéithe a bpléitear leo san alt tá an drámaíocht a úsáid mar scáthán ar an domhan, an malartú idirchultúrtha, seánra na drámaíochta clóiséid, gnéithe na hinlabharthachta agus na hintaibhitheachta, agus straitéisí eachtrannaithe. Lena chois sin, pléitear le ról an aistritheora agus leis na cineálacha éagsúla aistriúcháin .i. aistriúchán iomlán, lomaistriúchán nó cóiriú, a thagann i gceist. Is é aidhm an ailt seo, dá bhrí sin, eangach an taighde a chaitheamh níos faide amach chun comhthéacs agus múnla níos uileghabhálaí a sholáthar do dhrámaíocht aistrithe na Gaeilge

Translated drama under the spotlight: the case of Irish and other languages

Certain scholarly commentary suggests that a drama script only represents one piece of its entire story and, as a result, it is frequently not afforded a status equal to that assigned to other genres in literature. In the following article, the subject of drama, especially as it pertains to translation, will be discussed. International examples will be drawn upon to assert that drama deserves its own space within the field of literary endeavour and that it is not as easy as one might think to distinguish between literary and dramatic works. The difficulties in defining what is meant by drama as well as the complications involved in staging a drama will be illustrated. Even though Irish-language drama, particularly in Irish cities, has generally been considered as underground theatre down the years, examples from international drama will be used as a mechanism to compare and contrast them with Irish-language equivalents, thus demonstrating that Irish-language drama and international drama have many traits in common in this context

Anti-proliferative but not anti-angiogenic tyrosine kinase inhibitors enrich for cancer stem cells in soft tissue sarcoma.

BackgroundIncreasing studies implicate cancer stem cells (CSCs) as the source of resistance and relapse following conventional cytotoxic therapies. Few studies have examined the response of CSCs to targeted therapies, such as tyrosine kinase inhibitors (TKIs). We hypothesized that TKIs would have differential effects on CSC populations depending on their mechanism of action (anti-proliferative vs. anti-angiogenic).MethodsWe exposed human sarcoma cell lines to sorafenib, regorafenib, and pazopanib and assessed cell viability and expression of CSC markers (ALDH, CD24, CD44, and CD133). We evaluated survival and CSC phenotype in mice harboring sarcoma metastases after TKI therapy. We exposed dissociated primary sarcoma tumors to sorafenib, regorafenib, and pazopanib, and we used tissue microarray (TMA) and primary sarcoma samples to evaluate the frequency and intensity of CSC markers after neoadjuvant therapy with sorafenib and pazopanib. Parametric and non-parametric statistical analyses were performed as appropriate.ResultsAfter functionally validating the CSC phenotype of ALDHbright sarcoma cells, we observed that sorafenib and regorafenib were cytotoxic to sarcoma cell lines (P < 0.05), with a corresponding 1.4 - 2.8 fold increase in ALDHbright cells from baseline (P < 0.05). In contrast, we observed negligible effects on viability and CSC sub-populations with pazopanib. At low doses, there was progressive CSC enrichment in vitro after longer term exposure to sorafenib although the anti-proliferative effects were attenuated. In vivo, sorafenib improved median survival by 11 days (P < 0.05), but enriched ALDHbright cells 2.5 - 2.8 fold (P < 0.05). Analysis of primary human sarcoma samples revealed direct cytotoxicity following exposure to sorafenib and regorafenib with a corresponding increase in ALDHbright cells (P < 0.05). Again, negligible effects from pazopanib were observed. TMA analysis of archived specimens from sarcoma patients treated with sorafenib demonstrated significant enrichment for ALDHbright cells in the post-treatment resection specimen (P < 0.05), whereas clinical specimens obtained longitudinally from a patient treated with pazopanib showed no enrichment for ALDHbright cells (P > 0.05).ConclusionsAnti-proliferative TKIs appear to enrich for sarcoma CSCs while anti-angiogenic TKIs do not. The rational selection of targeted therapies for sarcoma patients may benefit from an awareness of the differential impact of TKIs on CSC populations