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Plant Species Classification Using Evolving Ensemble and Siamese Networks
Get PDFImage-based dried plant specimen identification poses a significant challenge due to the large number of possible classes and the extreme scarcity of labelled training samples. To tackle these limitations and mitigate classification biases, this research proposes a Particle Swarm Optimisation (PSO)-based weighted evolving ensemble model as well as a Siamese network for plant species classification. Specifically, we first diversify the base classifier pool by employing three networks, i.e. ResNet50, Xception, and VGG19, fine-tuned using the specimen samples. Besides the adoption of a mean average ensemble model, a weighted ensemble scheme with PSO-based optimal weighting factor generation is also utilised to integrate the outputs of the three base networks for tackling classification variances. In addition, to further tackle species classification with extremely imbalanced data, a Siamese network with ResNet50 as the backbone is utilised. Evaluated using a challenging FGVC6 data set with Melastomataceae images, the PSO-based weighted ensemble model is able to assign more influence to the best performing base networks for ensemble prediction and outperforms the traditional mean average ensemble method. Moreover, the Siamese network also obtains competitive performance for solving imbalanced specimen classification by performing comparing similarity scores between image embeddings
The phonological store of working memory:A critique and an alternative, perceptual-motor, approach to verbal short-term memory
Get PDFA key quality of a good theory is its fruitfulness, one measure of which might be the degree to which it compels researchers to test it, refine it, or offer alternative explanations of the same empirical data. Perhaps the most fruitful element of Baddeley and Hitch’s (1974) Working Memory framework has been the concept of a short-term phonological store, a discrete cognitive module dedicated to the passive storage of verbal material that is architecturally fractionated from perceptual, language, and articulatory systems. This review discusses how the phonological store construct has served as the main theoretical springboard for an alternative perceptual-motor approach in which serial recall performance reflects the opportunistic co-opting of the articulatory planning system and, when auditory material is involved, the products of obligatory auditory perceptual organisation. It is argued that this approach, which rejects the need to posit a distinct short-term store, provides a better account of the two putative empirical hallmarks of the phonological store—the phonological similarity effect and the irrelevant speech effect—and that it shows promise too in being able to account for nonword repetition and word-form learning, the supposed evolved function of the phonological store. The neuropsychological literature cited as strong additional support for the phonological store concept is also scrutinised through the lens of the perceptual-motor approach for the first time and a tentative articulatory-planning deficit hypothesis for the ‘short-term memory’ patient profile is advanced. Finally, the relation of the perceptual-motor approach to other ‘emergent-property’ accounts of short-term memory is briefly considered
The Nevell Manuscript:New Evidence of 17th-century Gentlewomen’s Music Book-Sharing and Education at Exiled English Convents
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Strategic narrative and public diplomacy:What Artificial Intelligence Means for the Endless Problem of Plural Meanings of Plural Things
Get PDFThis chapter advances a narrative approach to the study of public diplomacy. Webring together two phenomena: information disorder in communication, and order in world politics, to examine the challenges of narrating public diplomacy. We examine how actors can use tools of information disorder to further their strategic aims to shape international order. We do this in several ways. First, we set out these two (dis)order phenomena and their relationship. Second, we set out the dilemma of establishing and verifying truth claims in this information disorder. Third, we demonstrate why analysis of actors’ strategic narratives used in this context can explain how they are using information disorder to further their claims. Fourth and finally, we explore how generative artificial intelligence (AI) offers new tools for communication in foreign policy. It is important to examine both how actors use these tools, and how they try to control and direct the development of these tools. We argue that these tools add another dimension to a contested multipolarinternational order, one that extends a basic problem that generates politics: different people in different places prioritise different things and give things different meanings. Generative AI will not change this or solve this. This means an increasing complexity of communication since we wrote of strategic narrative in 2010. However, the distinct practices of actors using narratives to shape behaviour, and narratives being fundamental to how citizens view the world, remains unchanged
Co-creating conditions for social justice in digital societies:modes of resistance in HCI collaborative endeavors and evolving socio-technical landscapes
Get PDFIn this paper, we report on a three-year endeavour that fostered 18 collaborations between academic and non-academic organizations to co-create responses to social (in)justice issues in digital societies. The projects and range of individuals and organisations connected to this programme offer a snapshot of the state of social justice thinking within the UK digital economy research sector. Our analysis shows how the programme’s constellations of actions enacted different modes of resistance attempting to reshape people’s relationship to power dynamics, addressing institutions and exposing systems, and developing and restoring values for social justice. We explore how these efforts invite nuanced understanding of what constitutes resistance in knowledge co-production endeavours and how they helped surface tensions at the intersection of agencies and the distribution of responsibilities. Drawing from our insights and experience, we discuss implications for HCI concerned with the creation of the conditions for social justice in our digital societies
Stability of Electron and X-ray Emission in a LiTaO3 crystal-based pyroelectric accelerator driven by a periodically varying temperature
Get PDFConventional X-ray sources are bulky and require a high DC voltage. Pyroelectric X-ray generator technology has enabled us to develop portable, low-voltage X-ray sources for use in materials analysis, imaging, and other applications. The development of intense and reliable sources of charged particle beams is a current within accelerator physics in its own right. Changing the temperature of a single crystal of Lithium Tantalate (LiTaO3) in moderate vacuum conditions leads to generation of a strong electric field. If a metal target is placed nearby facing the crystal, the uncompensated polarization generated during the heating or cooling of the crystal causes the ejection of electrons from either the dielectric layer on the surface of the crystal or from the metal target depending on the polarity. These electrons are than accelerated by the strong electric field gaining an energy of up to 100 keV. The energy of these electrons can be determined by measuring the end-point energy of the X-ray spectrum that results from the interaction of the electrons with the target. It has been experimentally confirmed that a pyroelectric crystal installed in a chamber with a residual gas pressure of about 2 mTorr could be used to generate electrons with energy of up to 35 keV. Here, we present studies of the features of the electron flux in a pyroelectric accelerator and how they are affected by the pressure of the residual gas, and the distance between the crystal and the target. The connection between monoenergetic electron production in a pyroelectric generator and avalanche discharge in a gas is discussed. It is demonstrated that using a pair of crystals enables us to double the acceleration potential. Using the same setup an unknown sample was fluoresced using a pyroelectric accelerator in order to analyse its elemental content. In this report we demonstrate how pyroelectric accelerators can complement conventional X-ray tubes and radioisotopes or even large central facilities. Pyroelectric X-ray generator technology is currently being developed to provide a reliable, compact, stable, and reproducible X-ray source with controllable parameters, which does not require a high-voltage DC voltage or the use of hazardous (radioactive) materials.<br/
The Everyday Security of Living With Conflict
Get PDFWhen ‘cyber’ is used as a prefix, attention is typically drawn to the technological and spectacular aspects of war and conflict – and, by extension, security. We offer a different approach to engaging with and understanding security in such contexts, by foregrounding the everyday – mundane – experiences of security within communities living with and fleeing from war. We do so through three vignettes from our field research in Colombia, Lebanon and Sweden, respectively, and by highlighting the significance of ethnography for security research with communities living in regions afflicted by war. We conclude by setting out a call to action for security researchers and practitioners to consider such lived experiences in the design of security technology that aims to cater to the needs of communities in ‘global conflict and disaster regions’.---Cuando se usa el prefijo ‘ciber-’, suele centrarse la atención en los aspectos tecnológicos y espectaculares de la guerra y el conflicto - y, por extensión, en la seguridad. Sin embargo, en este artículo ofrecemos un enfoque diferente para abordar y comprender la seguridad en estos contextos, al tomar en cuenta y resaltar las experiencias cotidianas – mundanas – de seguridad dentro de las comunidades que viven en guerra o huyen de ella. Lo hacemos a través de tres casos de nuestras investigaciones de campo en Colombia, Líbano y Suecia, respectivamente, resaltando la importancia de la etnografía para la investigación sobre seguridad en comunidades que viven en regiones afligidas por la guerra. Concluimos con un llamado a la acción para que los investigadores y profesionales en el área de la seguridad consideren estas experiencias vividas en el diseño de tecnologías de seguridad que buscan atender las necesidades de las comunidades en 'regiones afectadas por conflictos y desastres a nivel mundial
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