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Creating authentic historical costumes to augment virtual humans for cultural heritage
No full textBenefiting from the simulation of 3D technologies, the evolution of virtual humans allows them to have a realistic human-like appearance and behaviour, interacting with users and the environment. Today, the application of digital avatars has expanded to computer visualization exhibitions, movies, animations, game engines, etc. This paper investigates a methodology for applying virtual humans to support the digital reconstruction of cultural heritage in virtual reality applications, focusing on converting 2D design sketches of historical costumes into a tangible reality within an immersive VR environment. Through the creation and application of authentic historical outfits, this approach enriched the authenticity of digital avatars, and further expanded the interpretation and representation of cultural heritage for educational and cultural institutions. In addition, this paper evaluated the impacts of avatars on enhancing learning and visiting experiences on the promotion of cultural history diversity. This research is beneficial for exploring how immersive VR technologies bring about equitable quality education and promote learning opportunities in the context of cultural heritage. At the time of writing, the results of this research are adopted in immersive exhibits in the Timespan Museum, West Highland Museum, Finlaggan Museum and Taigh Chearsabhagh, aimed at providing an immersive virtual time travel experience to strengthen lifelong cultural education values and further support the sustainable development goals
Anaerobic decomposition dynamics of three kelp species from the North-east Atlantic:implications for blue carbon storage
No full textDecomposition pathways of detritus are key processes in the contribution of macroalgal habitats to natural carbon sequestration of “blue carbon”. The anaerobic decomposition of three North-east Atlantic canopy-forming kelp species was investigated using ex-situ decomposition chambers. Thallus parts (stipes, holdfasts and blades) of Laminaria hyperborea, Saccharina latissima and Laminaria digitata were incubated in still seawater in temperature-controlled dark conditions. Refractory potential (Rp), first-order decomposition rate ‘k’ and associated half-life (t1/2) were calculated. Dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) were measured in the incubation water at 0, 7, 14 and 21 days and thermal gravimetric profiles were determined at each 26 decomposition stage. Oxygen depletion occurred within 24 hours. Approximately 5 times as much DOC was released than DIC. Holdfast material produced the most DIC, while blade material released greatest amounts of DOC. Saccharina latissima released less DOC than L. hyperborea and L.digitata. The refractory potential of fragments increased from Rp = 0.46 ± 0.05 (SD) to 0.50 ± 0.04 (SD) throughout the 21-day incubations. Saccharina latissima had the highest Rp throughout. First order decomposition rates, averaged across the three kelp species, gave half-lives (t1/2) for blade fragments of 27.8 ± 2.9 days, (k = 0.025 ± 0.002) and stipes (t1/2) as 113.2 ± 21.1 days (k = 0.006 ± 33 0.001). This experiment clarifies the fate of macroalgal carbon during early decomposition and thus the processes that govern blue carbon pathways of macroalgae highlighting the differences in species and thallus parts breakdown
New results on non-disjoint and classical strong external difference families
No full textClassical strong external difference families (SEDFs) are much-studied combinatorial structures motivated by information security applications; it is conjectured that only one classical abelian SEDF exists with more than two sets. Recently, non-disjoint SEDFs were introduced; it was shown that families of these exist with arbitrarily many sets. We present constructions for both classical and non-disjoint SEDFs, which encompass all known non-cyclotomic examples for either type (plus many new examples) using a sequence-based framework. Moreover, we introduce a range of new external difference structures (allowing set-sizes to vary, and sets to be replaced by multisets) in both the classical and non-disjoint case, and show how these may be applied to various communications applications
The psychic lives of statues:reckoning with the rubble of empire
No full textFrom Cape Town to Bristol and Richmond, statues have become sites of resistance and contestation of our imperial past and postcolonial present. The Psychic Lives of Statues by Rahul Rao offers an insightful exploration of these global controversies, demonstrating that beneath their surface lie deeper struggles over race, caste, and the politics of decolonisation.Rao takes readers on a journey through South Africa, England, the US, Ghana, India, Australia, and Scotland, revealing how statue controversies have dramatically rearranged the canon of anticolonial political thought. By examining these debates through a personal and literary lens, Rao addresses the multifaceted issues of justice, cultural memory, and belonging.The Psychic Lives of Statues examines both the toppling of colonial statues and the raising of postcolonial ones, demonstrating that the statue form as a medium of representation and a bid for immortality is by no means obsolete. Engaging with artists, scholars, and activists, Rao provides fresh perspectives on how societies grapple with and reinterpret the past and present through iconography
What are sub-national island jurisdictions?
No full textThere is no consensus about the definition and classification of Sub-National Island Jurisdictions (SNIJs). This may conflate academic and policy analysis and misguide policies to advance development. We review existing definitions and classifications of SNIJs and systematically analyze the criteria used in different studies. Our study finds several inconsistencies in existing lists of entities labelled as SNIJs. This shows it may be helpful to arrive at common ground as to what might constitute an SNIJ. We suggest to define an SNIJ as a non-sovereign populated island territory that possesses some degree of autonomy in a partnership with a parent state. SNIJs have their own identity and culture, which are distinct from the parent state. They often are former colonies and may freely move towards independence. This definition can be used as a starting point for further analysis and of SNIJs that can help study them and design policies that address their challenges.</p
An evaluation of domain-agnostic representations to enable multi-task learning in combinatorial optimisation
No full textWe address the question of multi-task algorithm selection in combinatorial optimisation domains. This is motivated by a desire to simplify the algorithm-selection pipeline by developing a more general classifier that does not require specialised information per domain, and the potential for transfer learning. A minimum requirement to achieve this is to find a common representation for describing instances from multiple domains. We assess the strengths and weaknesses of three candidate representations (text, images and graphs) which can all be used to describe three different application domains. Two setups are considered: single-task selection where one classifier is trained per domain, each using the same representation, and multi-task selection where a single classifier is trained with data from all three domains to output the best solver per instance. We find that the domain-agnostic representations perform comparably with domain-specific feature-based classifiers with the benefit of providing a generic representation that does not require feature identification or computation, and could be extended to additional domains in future
A new data-driven paradigm for the study of avian migratory navigation
No full textAvian navigation has fascinated researchers for many years. Yet, despite a vast amount of literature on the topic it remains a mystery how birds are able to find their way across long distances while relying only on cues available locally and reacting to those cues on the fly. Navigation is multi-modal, in that birds may use different cues at different times as a response to environmental conditions they find themselves in. It also operates at different spatial and temporal scales, where different strategies may be used at different parts of the journey. This multi-modal and multi-scale nature of navigation has however been challenging to study, since it would require long-term tracking data along with contemporaneous and co-located information on environmental cues. In this paper we propose a new alternative data-driven paradigm to the study of avian navigation. That is, instead of taking a traditional theory-based approach based on posing a research question and then collecting data to study navigation, we propose a data-driven approach, where large amounts of data, not purposedly collected for a specific question, are analysed to identify as-yet-unknown patterns in behaviour. Current technological developments have led to large data collections of both animal tracking data and environmental data, which are openly available to scientists. These open data, combined with a data-driven exploratory approach using data mining, machine learning and artificial intelligence methods, can support identification of unexpected patterns during migration, and lead to a better understanding of multi-modal navigational decision-making across different spatial and temporal scales
Breaking the capacity limit for WO<sub>3</sub> anode-based Li-ion batteries using photo-assisted charging
No full textThe capacity of a metal ion battery is limited by fundamental parameters. Various strategies have been employed to maximise energy storage, including manufacturing control and investigating the components within the battery system. Recent developments have focused on incorporating photoactive materials into battery architectures to enhance energy density. However, challenges remain in material selection and processing for high-performance electrodes. Here, we show that hydrothermally produced WO3 is a safe, low-cost material with excellent photo-battery performance. Under illumination, the battery achieves a capacity of 1150 mAh g⁻¹ at 0.1C and 800 mAh g⁻¹ at 1C, exceeding the theoretical limit (693 mAh g⁻¹). The battery exhibits excellent cycling stability, retaining a capacity of 623 mAh g⁻¹ after 400 cycles at 1C. Using Randles-Sevcik and electrochemical impedance spectroscopy, we show that enhanced carrier mobility contributes to the observed capacity beyond the theoretical limit. The photo-conversion efficiency of the battery is 5.96%. Our results demonstrate that light can be used to enhance the capacity of an ion battery system beyond its theoretical limit. This approach can significantly boost the energy storage density of various metal-ion batteries. Moreover, in systems with inherently slow metal-ion diffusion, such as multi-valent systems, photoenhanced charging can make these technologies more competitive
Accounting for non-random samples with distance sampling to estimate population density
No full text1. A critical assumption of standard distance sampling is that sampling lines are located such that animals are uniformly distributed as a function of distance from the line. Failure to meet this assumption can introduce bias in the estimator.2. Many studies have used landscape features, such as roads or rivers, as lines, which can violate assumptions of distance sampling in two ways. First, animals may be attracted or repelled by the landscape feature due to human activity (e.g. along roads) or habitat characteristics associated with the feature (e.g. rivers). Second, sampling along landscape features may not be representative of the larger area of interest.3. We used auxiliary data to generalize the distance sampling estimator and relax assumptions of a uniform distribution of animals relative to distance from the line (i.e. density gradient) and to allow the distribution of animals to differ by habitat type. The generalized estimator provides unbiased estimates of density within the area sampled but may not be representative of the study area.4. To address the problem of landscape features providing unrepresentative sampling, we used a resource selection model to estimate the proportion of the population that occurred within the surveyed area to obtain an estimate of abundance for the desired area of inference.5. We demonstrate our modified distance sampling estimator using white-tailed deer (Odocoileus virginianus) in a 972-km2 study area. We conducted infrared surveys of deer from roads to collect distance-to-transect data. We used locations of radio-collared deer to model the distribution of deer relative to the transects and to develop a resource selection model of deer based on distance to roads, habitat type, elevation and slope to account for roads being a non-representative sample of the study area.6. Synthesis and applications. When using landscape features as survey lines, the density gradient and deer distribution can introduce either positive or negative bias, which makes it impossible to assess the bias introduced without auxiliary data. The estimator we developed can improve precision because we obtained a better fit to distance observations and accounts for non-random placement of transects with minimal loss of precision