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Translating CPS with Shared-Variable Concurrency in SpaceEx
No full textCyber-physical systems (CPS), combining continuous physical behavior and discrete control behavior, have been widely utilized in recent years. However, the traditional modeling languages used to specify discrete systems are no longer applicable to CPS, since CPS subsume the combination of the cyber and the physical. To address this, a modeling language for CPS based on shared variables is proposed. In this paper, we present an implementation of this language in SpaceEx. Thus, a bridge between our language and hybrid automata is established.<br/
Fairness-Aware Data Integration
No full textMachine learning can be applied in applications that take decisions that impact people’s lives. Such techniques have the potential to make decision making more objective, but there also is a risk that the decisions can discriminate against certain groups as a result of bias in the underlying data. Reducing bias, or promoting fairness, has been a focus of significant investigation in machine learning, for example based on pre-processing the training data, changing the learning algorithm, or post-processing the results of the learning. However, prior to these activities, data integration discovers and integrates the data that is used for training, and data integration processes have the potential to produce data that leads to biased conclusions. In this paper, we propose an approach that generates schema mappings in ways that take into account: (i) properties that are intrinsic to mapping results that may give rise to bias in analyses; and (ii) bias observed in classifiers trained on the results of different sets of mappings. The approach explores a space of different ways of integrating the data, using a tabu search algorithm, guided by bias-aware objective functions that represent different types of bias.The resulting approach is evaluated using Adult Census and German Credit datasets, to explore the extent to which and the circumstances in which the approach can increase the fairness of the results of the data integration process
A Perspective on Welding Technology Challenges in the Nuclear Sector
No full textThis article describes three areas that, in the opinion of the author, should be priorities for development in the nuclear sector. The application of electron-beam (or laser in vacuo) welding to pressure vessel fabrication; the optimisation of filler metal compositions for multipass steel welds; and the pre-fabrication of dissimilar metal transition pieces are each highlighted and discussed. While conceived with the nuclear sector in mind, these priority areas are relevant more generally to the welding of pressure vessels, piping and similar structures. The intention is to stimulate ideas, to provoke debate, and to encourage the welding community to rise to the challenges that must be overcome as we transition to a low-carbon future
Ageing in Place over time::The making and unmaking of home
No full text‘Ageing in place’ is a key component of UK policy, aimed at supporting older people to remain living in their own homes and communities for as long as possible. Although wide-ranging, the scholarly literature in this field has not sufficiently examined the interconnections between ageing in place and the changing experience of ‘home’ over time. This paper addresses this gap in a novel way by bringing together qualitative secondary analysis of longitudinal data with critical literature on ‘home’ and Mason’s (2018) cutting-edge theories of ‘affinities’ to understand the multi-dimensionality of home in relation to ageing in place. The paper makes significant methodological, empirical, and theoretical contributions to the field of scholarship on home, by demonstrating how homes are made and unmade over time. Discussions of home emerged organically in the longitudinal data that focused on people’s travel and transport use, allowing our qualitative secondary analysis approach to look anew at how experiences of home are dynamically shaped by people’s potent connections inside and outside the dwelling. Presenting an empirical analysis of four case studies, the paper suggests that future discussions in the field of ageing in place should pay closer attention to the factors which shape experiences of the un/making of home over time, such as how deteriorating physical and mental health can shape how people experience their dwelling and neighbourhood as well as their relationships across these settings.<br/
Augmenting a Nature Documentary with a Lifelike Hologram in Virtual Reality
No full textWhile augmented reality television (ARTV) is being investigated in research labs, the high cost of AR headsets makes it difficult foraudiences to benefit from the research. However, the relative affordability of virtual reality (VR) headsets provides ARTV researcherswith opportunities to test their prototypes in VR. Additionally, as VR becomes an acceptable medium for watching conventional TV,augmenting such viewing experiences in VR creates new opportunities. We prototype a nature documentary ARTV experience inVR and conduct a remote user study (𝑛 = 10) to investigate six points on the visual display design dimension of presenting a lifelikeprogramme-related hologram. We manipulated the starting point and the movement behaviour of the hologram to gain insight intoviewer preferences. Our findings highlight the importance of personal preferences and that of the perceived role of a hologram inrelation to the underlying TV content; suggesting there may not be a single way to augment a TV programme. Instead, creators mayneed to provide the audiences with capabilities to customise ARTV content
Measuring the structural complexity of music: fromstructural segmentations to the automatic evaluation of models for music generation
No full textTuning porosity of coal-derived activated carbons for CO2 adsorption
No full textA simple method was developed to tune the porosity of coal-derived activated carbons (ACs), which provided a model adsorbent system to investigate the volumetric CO2 adsorption performance. Specifically, the method involved the variation of the activation temperature in a K2CO3 induced chemical activation process which could yield ACs with defined microporous (<2 nm, including ultra-microporous <1 nm) and meso-micro-porous structures. CO2 adsorption isotherms revealed that the microporous AC has the highest measured CO2 adsorption capacity (6.0 mmol·g–1 at 0 °C and 4.1 mmol·g–1 at 25 °C), whilst ultra-microporous AC with a high packing density exhibited the highest normalized capacity with respect to packing volume (1.8 mmol·cm−3 at 0 °C and 1.3 mmol·cm–3 at 25 °C), which is significant. Both experimental correlation analysis and molecular dynamics simulation demonstrated that (i) volumetric CO2 adsorption capacity is directly proportional to the ultra-micropore volume, and (ii) an increase in micropore sizes is beneficial to improve the volumetric capacity, but may lead a low CO2 adsorption density and thus low pore space utilization efficiency. The adsorption experiments on the ACs established the criterion for designing CO2 adsorbents with high volumetric adsorption capacity.Keywords coal-derived activated carbons, porosity, CO2 adsorption, molecular dynamics<br/
‘Enter Parliament but never become part of it’: How have the Greens in the UK Approached Opposition?
No full textThe Greens in the UK have benefited from the fragmentation of the party system and the creation of devolved institutions, achieving consistent representation at multiple levels of British politics in recent years. However, we know little about what they have done in these positions. This study uses interviews with Green legislators to investigate how they have interpreted the task of opposition at Westminster, Holyrood and Stormont. We show that Green legislators’ approaches to opposition have been influenced by their party identity, and that differences in approach between the institutions have largely been determined by contrasting political opportunity structures, rather than parliamentary rules. These findings highlight the importance of party as a factor shaping opposition strategy and the varied roles which opposition parties can play within the UK political system
Summary of Model Checking C++ Programs
No full textThis is an extended abstract of the article “Model Checking C++ Programs” by Felipe R. Monteiro, Mikhail R. Gadelha, and Lucas C. Cordeiro. We describe and evaluate anovel verification approach based on bounded model checking (BMC) and satisfiability modulo theories (SMT) to verify C++ programs. Our verification approach analyzes bounded C++ programs by encoding into SMT various sophisticated features that the C++ programming language offers, such as templates, inheritance, polymorphism, exception handling, and the StandardTemplate Libraries. We implemented our verification approach on top of ESBMC. We compare ESBMC to LLBMC and DIVINE, which are state-of-the-art verifiers to check C++ programs directly from the LLVM bitcode. Experimental results show thatESBMC can handle a wide range of C++ programs, presenting a higher number of correct verification results. Additionally, ESBMC has been applied to a commercial C++ application in the telecommunication domain and successfully detected arithmeticoverflow errors, which could lead to security vulnerabilities.Index Terms—C++, memory safety, model checking, SMT, software verification<br/
Clinical challenges associated with utility of neoadjuvant treatment in patients with pancreatic ductal adenocarcinoma
No full textPancreatic ductal adenocarcinoma (PDAC) is an increasingly common cancer with a persistently poor prognosis, and only approximately 20% of patients are clearly anatomically resectable at diagnosis. Historically, a paucity of effective therapy made it inappropriate to forego the traditional gold standard of upfront surgery in favour of neoadjuvant treatment; however, modern combination chemotherapy regimens have made neoadjuvant therapy increasingly viable. As its use has expanded, the rationale for neoadjuvant therapy has evolved from one of `downstaging` to one of early treatment of micro-metastases and selection of patients with favourable tumour biology for resection. Defining resectability in PDAC is problematic; multiple differing definitions exist. Multidisciplinary input, both in initial assessment of resectability and in supervision of multimodality therapy, is therefore advised. European and North American guidelines recommend the use of neoadjuvant chemotherapy in borderline resectable (BR)-PDAC. Similar regimens may be applied in locally advanced (LA)-PDAC with the aim of improving potential access to curative-intent resection, but appropriate patient selection is key due to significant rates of recurrence after excision of LA disease. Upfront surgery and adjuvant chemotherapy remain standard-of-care in clearly resectable PDAC, but multiple trials evaluating the use of neoadjuvant therapy in this and other localised settings are ongoing