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Designing progressive model elicitation tools to support complex cognitive activities
Get PDFFunding: This research was supported by NSERC (The Natural Sciences and Engineering Research Council of Canada) RGPIN-2020-04401 and EPSRC (Engineering and Physical Sciences Research Council) EP/T518062/1.Externalizations such as sketches and diagrams are effective in helping individuals plan for complex projects and designs. Offloading complex information on a different medium (e.g. paper) frees up cognitive resources for sophisticated thinking. However, there are significant challenges in effectively using externalizations and notations (formalized externalizations). It is difficult to envision formal representations of complex ideas at the beginning and it is also hard to keep track of evolutions within notations. In addition, existing notations may be insufficient or inflexible for our specific purposes. We call instances of such thinking in which humans have to work through complex information and action space as instances of "Progressive Model Elicitation" (PME). We explore ways to support PME processes by presenting a set of design principles and Schematica, a prototype that implements those design principles to support PME. We present illustrative examples of Schematica use to support the process of PME
Interaction of triazole corrosion inhibitors with metallic and bimetallic surfaces under ideal and realistic conditions
No full textWhile copper and copper based alloys generally have good corrosion resistance compared to ferrous alloys, in harsh conditions they do undergo corrosion. Molecular corrosion inhibitors can be used to combat this; an important class of corrosion inhibitors is triazoles. In this project, the interactions of several triazole compounds – benzotriazole (BTAH), tolyltriazole (TTAH), and 1,2,4-triazole – with copper and bimetallic surfaces were investigated under ideal and realistic conditions. Analytical techniques used included scanning tunnelling microscopy (STM), high-resolution electron energy loss spectroscopy (HREELS), x-ray photoelectron
spectroscopy (XPS), medium energy ion scattering (MEIS), and transmission electron microscopy (TEM) with energy dispersive x-ray spectroscopy (EDS). Additionally, computational modelling using density functional theory (DFT) was done to support the experiments. It was found that the presence of zinc is very important when using BTAH and TTAH. On a single crystal surface under UHV condition with both copper and zinc present, BTAH appears to preferentially form surface structures with zinc rather than copper. In experiments using more realistic conditions, TTAH appears to form a much less effective passivation layer on brass when compared with copper and bronze. This is in stark contrast to tin, which does not significantly participate in the passivation layer on bronze. In experiments on a Cu(111) surface, TTAH was found to behave similarly to BTAH, albeit with less precise ordering; this indicates that studies using BTAH are relevant to TTAH. 1,2,4-triazole was found to form ordered structures on a Cu(111) surface, although it does so less readily than BTAH and the structures are not stable to as high a temperature."I am grateful to Lubrizol Limited for providing funding for this project. I am also grateful to the University of St Andrews and the School of Chemistry for funding via a Handsel Scholarship."--Fundin
Projection algebras and free projection- and idempotent-generated regular ∗-semigroups
Get PDFFunding: This work was supported by the following grants: Future Fellowship FT190100632 of the Australian Research Council; EP/V032003/1, EP/S020616/1 and EP/V003224/1 of the Engineering and Physical Sciences Research Council. The second author thanks the Sydney Mathematical Research Institute, the University of Sydney and Western Sydney University for partially funding his visit to Sydney in 2023 during which part of this research was undertaken.The purpose of this paper is to introduce a new family of semigroups—the free projection-generated regular ∗- semigroups -and initiate their systematic study. Such a semigroup PG(P) is constructed from a projection algebra P, using the recent groupoid approach to regular ∗-semigroups. The assignment P → PG(P) is a left adjoint to the forgetful functor that maps a regular ∗-semigroup S to its projection algebra P (S). In fact, the category of projection algebras is coreflective in the category of regular ∗-semigroups. The algebra P (S) uniquely determines the biordered structure of the idempotents E (S), up to isomorphism, and this leads to a category equivalence between projection algebras and regular ∗-biordered sets. As a consequence, PG(P) can be viewed as a quotient of the classical free idempotent-generated (regular) semigroups IG(E) and RIG(E), where E = E (PG(P)); this is witnessed by a number of presentations in terms of generators and defining relations. The semigroup PG(P) can also be interpreted topologically, through a natural link to the fundamental groupoid of a simplicial complex explicitly constructed from P. The above theory is illustrated on a number of examples. In one direction, the free construction applied to the projection algebras of adjacency semigroups yields a new family of graph-based path semigroups. In another, it turns out that, remarkably, the Temperley–Lieb monoid ℒn is the free regular ∗-semigroup over its own projection algebra P (ℒn).Peer reviewe
Ephemeral node identifiers for enhanced flow privacy
Get PDFThe Internet Protocol (IP) uses numerical address values carried in IP packets at the network layer to allow correct forwarding of packets between source and destination. Those address values must be kept visible in all parts of the network. By definition, those addresses must carry enough information to identify the source and destination for the communication. This means that successive flows of IP packets can be correlated - it is possible for an observer of the flows to easily link them to an individual source and so, potentially, to an individual user. To alleviate this privacy concern, it is desirable to have ephemeral address values - values that have a limited lifespan and so make flow correlation more difficult for an attacker. However, the IP address is also used in the end-to-end communication state for transport layer flows so must remain consistent to allow correct operation at the transport layer. We present a solution to this tension in requirements by the use of ephemeral Node Identifier (eNID) values in IP packets as part of the address value. We have implemented our approach as an extension to IPv6 in the FreeBSD14 operating system kernel. We have evaluated the implementation with existing applications over both a testbed network in a controlled environment, as well as with global IPv6 network connectivity. Our results show that eNIDs work with existing applications and over existing IPv6 networks. Our analyses shows that using eNIDs creates a disruption to the correlation of flows and so effectively perturbs linkability. As our approach is a network layer (layer 3) mechanism, it is usable by any transport layer (layer 4) protocol, improving privacy for all applications and all users.Peer reviewe
Pausanias' haptic geography : bodies and landscapes in the Periegesis
Get PDFPausanias has often been represented, by the standards of modern travel writing, as an author who is reticent about describing his personal experiences. There have been some important attempts to reassert the experiential nature of his account, but there is still a tendency to understate the importance of bodies and bodiliness for his text. Repeatedly Pausanias offers us images of mythical and historical bodies immersed in the landscapes he passes through. Every so often, interspersed with those passages, we come across moments where the land is equated with a human body. My aim is to explore the function of those passages within Pausanias’ text. I argue that they imply a conception of antiquarian travel as a surprisingly corporeal enterprise, in the sense that Pausanias appeals repeatedly to the reader’s haptic imagination. I further argue that these passages play an important role in articulating Pausanias’ distinctive vision of the continuing but always elusive presence of the past in the landscapes of Roman Greece. Pausanias has a powerful sense of the permeability between human bodies and the environment and, intertwined with that theme, often articulated through it, an awareness of the permeability between the past and the present.Peer reviewe
Animal culture : conservation in a changing world
Get PDFFunding: P.B. is supported by Whale and Dolphin Conservation. L.A. is supported by the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract number MB22.00056. E.L.C. is supported by a Royal Society New Zealand Rutherford Discovery Fellowship. A.L.G. is supported by the San Diego Zoo Wildlife Alliance. E.C.G. is supported by a Royal Society University Research Fellowship (UF160081 & URF\R\221020).Social learning and animal culture can influence conservation outcomes in significant ways. Culture is a dynamic phenomenon; socially learned behaviours can be transmitted within and/or between generations and among populations, which can facilitate resilience, or in other circumstances generate vulnerability. Culture can be a driver of evolutionary diversification, population structure and demography, shaping sociality and influencing underlying biological processes such as reproduction and survival, affecting fitness. This theme issue synthesizes the current state of knowledge on cultural variation within major vertebrate taxa, offering practical insights on how social learning can interface directly with conservation interventions. It ranges over topics that include translocations, human–wildlife interactions and adaptation to anthropogenic change. Culture is complex; integrating cultural processes into conservation is challenging. No one-size-fits-all policy can be recommended. Instead, we aim to balance current understanding of underlying processes with a diversity of practical implementations in this nascent field, exploring and supporting developing pathways towards conservation efficiencies. Key themes that emerge include conserving cultural capacity, benefits of data sharing, along with the intrinsic value of animal cultures and the role of Indigenous Peoples and local communities. This article is part of the theme issue ‘Animal culture: conservation in a changing world’.Peer reviewe
Integrating cultural dimensions in sperm whale (Physeter macrocephalus) conservation : threats, challenges and solutions
Get PDFFunding: A.E. was funded by the Killam Graduate Research Scholarship, Nova Scotia Graduate Scholarship and the Rufford Grant. M.C. was supported by the Marine Mammal Research Program Fund and the Jungers Faculty Development and Research Fund at Oregon State University. T.A.H. was supported by the Oregon Gray Whale License Plate Program at the Marine Mammal Institute (Oregon State University). S.L.M was funded by the National Marine Fisheries Service, NOAA.Culture—socially transmitted behaviours shared within a community—can influence animal populations' structure, vulnerability and resilience. Clans of sperm whales in the Eastern Tropical Pacific (ETP) exemplify the profound influence of culture on these dynamics and highlight the challenges of accounting for culture in conservation efforts. Globally, sperm whales are classified as vulnerable, and the ETP sperm whale population has struggled to reach a positive growth rate. This stagnation is partly due to cumulative anthropogenic threats in the region, including fishing conflicts, vessel traffic, pollution, deep sea mining, oil and gas exploration, and anthropogenic climate change. The United Nations Convention on Migratory Species adopted a Concerted Action for ETP sperm whales in 2017, proposing collaborative efforts to address cultural dimensions in conservation. However, knowledge gaps and real-world implementation challenges persist. Here, we review the role of social transmission in shaping sperm whale behaviour and populations, outline current anthropogenic threats and environmental stressors they face in the ETP, and discuss the ongoing challenges of incorporating cultural dimensions into large-scale international conservation efforts. Strengthening transnational collaboration and capitalizing on new technologies for efficient analysis can help bridge these knowledge gaps and enhance future research on this iconic species. This article is part of the theme issue ‘Animal culture: conservation in a changing world’.Peer reviewe
Non-existence of the box dimension for dynamically invariant sets
Get PDFFunding: The author was supported by an EPSRC Standard Grant EP/R015104/1.One of the key challenges in the dimension theory of smooth dynamical systems lies in establishing whether or not the Hausdorff, lower and upper box dimensions coincide for invariant sets. For sets invariant under conformal dynamics, these three dimensions always coincide. On the other hand, considerable attention has been given to examples of sets invariant under nonconformal dynamics whose Hausdorff and box dimensions do not coincide. These constructions exploit the fact that the Hausdorff and box dimensions quantify size in fundamentally different ways, the former in terms of covers by sets of varying diameters and the latter in terms of covers by sets of fixed diameters. In this article we construct the first example of a dynamically invariant set with distinct lower and upper box dimensions. Heuristically, this says that if size is quantified in terms of covers by sets of equal diameters, a dynamically invariant set can appear bigger when viewed at certain resolutions than at others.Peer reviewe
Navigating faith and identity : religious commitment, departure, and belief negotiation within the Seventh-day Adventist community
No full textThis research explores the complex process of navigating faith and identity within the Seventh-day Adventist (SDA) community, with particular focus on individuals considering disaffiliation. It examines the negotiable and non-negotiable aspects of Adventist identity, practice, and worldview, highlighting how these elements shape decisions to remain within or leave the faith tradition. Unlike conventional models of religious change that emphasize external transitions, this study underscores the significance of internal faith identity negotiation, driven by the interplay between personal beliefs and communal expectations.
Through qualitative methodologies, including interviews with former and current SDA members and regional church leaders from England, Hungary, and Romania, the study uncovers key factors influencing faith retention, navigation, or departure. The findings reveal that disaffiliation often arises from internal conflicts rather than the appeal of alternative religious traditions. Many individuals navigate a reworking of their Adventist worldview, maintaining core elements such as the Cosmic Conflict narrative while reevaluating flexible aspects of doctrine and practice.
Worldview theory serves as a crucial framework in understanding the negotiation of belief within Adventism, particularly the tension between personal conviction and institutional identity. By exploring the dynamics of conversion, deconversion, and religious switching, this research highlights how flexible elements within belief systems influence faith transitions. The study situates these processes within the broader context of SDA theology and community life, revealing how worldview negotiation impacts both personal and communal spiritual identities.
This research also critiques SDA leadership’s insufficient recognition of growing disillusionment within the community, calling for a more empathetic and inclusive approach to address diverse spiritual experiences. By framing disaffiliation as a process of spiritual evolution rather than rejection, the study illuminates the transformative potential of belief negotiation. It contributes to religious studies by providing a nuanced understanding of intra-denominational change, faith retention, and the dynamics of belief transformation within Adventism
More positive and less variable North Atlantic Oscillation at high CO2 forcing
Get PDFFunding: IM is supported by a Harry Hess postdoctoral fellowship from Princeton Geosciences. The work of LMP is supported, in part, by a grant from the US National Science Foundation to Columbia University.The North Atlantic Oscillation (NAO) is the principal mode of atmospheric variability over the North Atlantic, modulating the weather and climate of neighboring regions in both winter and summer. While Earth System Models generally project a more positive NAO under 21st century high-emission scenarios, uncertainties persist as to the precise response of the NAO to increased CO2 levels, owing to large internal variability. In this study we investigate the response of the NAO to a wide range of CO2 forcings, from two to eight times the preindustrial values. Analyzing a large sample of present-generation climate models, we find that the NAO likely becomes more positive with increasing CO2 concentrations. Moreover, we find a reduction in NAO variability. This leads to a smaller increase in the likelihood of extremely positive NAO events than would be expected based solely on the shift in the mean. On the other hand, we also find a reduction in extremely negative NAO events, which is attributable to both the shift toward more positive values and the decrease in variance. Finally, our analysis reveals that the distribution of the NAO response at high CO2 forcing is negatively skewed. This fact partially offsets the decrease in extremely positive NAO events associated with reduced variability. Ultimately, our results suggest a greater increase in positive NAO events compared to the decrease in extremely negative NAO events at higher CO2 forcing.Peer reviewe
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