455 research outputs found

    Adaptive sampling in context-aware systems: a machine learning approach

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    As computing systems become ever more pervasive, there is an increasing need for them to understand and adapt to the state of the environment around them: that is, their context. This understanding comes with considerable reliance on a range of sensors. However, portable devices are also very constrained in terms of power, and hence the amount of sensing must be minimised. In this paper, we present a machine learning architecture for context awareness which is designed to balance the sampling rates (and hence energy consumption) of individual sensors with the significance of the input from that sensor. This significance is based on predictions of the likely next context. The architecture is implemented using a selected range of user contexts from a collected data set. Simulation results show reliable context identification results. The proposed architecture is shown to significantly reduce the energy requirements of the sensors with minimal loss of accuracy in context identification

    Also By The Same Author: AKTiveAuthor, a Citation Graph Approach to Name Disambiguation

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    The desire for definitive data and the semantic web drive for inference over heterogeneous data sources requires co-reference resolution to be performed on those data. In particular, name disambiguation is required to allow accurate publication lists, citation counts and impact measures to be determined. This paper describes a graph-based approach to author disambiguation on large-scale citation networks. Using self-citation, co-authorship and document source analyses, AKTiveAuthor clusters papers, achieving precision of 0.997 and recall of 0.818 over a test group of eight surname clusters

    A low-power, distributed, pervasive healthcare system for supporting memory

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    With age, injury, or disease, human memory can be significantly impaired. Current coping strategies range from simple aids such as post-it notes and calendars to, more recently, assistive devices which attempt to provide reminders at appropriate times, capture details of important events, or aid with performing complex tasks. In this paper we extend the state of the art by reporting on a pervasive system designed to 'orientate' a person with memory problems by reminding them in real time of details and personal memories of their surroundings. We describe a three-level architecture, consisting of a novel wearable sensing device, mobile phone, and Internet service, where each level is less constrained in terms of energy and offers greater computational capability. This kind of distributed architecture for a memory aid has not been reported before. The wearable device typically draws 38.5mA of current, allowing a full day's operation on a single charge. We demonstrate the operation of the system, which successfully identifies the faces of those nearby and shows their names on the mobile phone

    DejaView: Help with memory, when you need it

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    Promising findings in the use of wearable memory aids such as SenseCam have been widely reported. However, to date, there has been relatively little consideration of the potential for offering memory help in real-time during daily living. Such assistance, in the form of proactive visual prompts comprising the four reported types of cue (people, places, objects, and actions), could help people with memory problems to immediately orientate themselves in a situation -- supplying details of where they are, or who they are with. This paper reports on the three-tier DejaView system, designed to provide such help.DejaView works across a wearable device, a smartphone, and a remote computer, simultaneously recording a lifelog, finding appropriate cues from past experiences, and feeding relevant information back to the user. The real-time nature of this system required the design of a new wearable device, similar to SenseCam but more customisable and additionally capable of transmitting data over Bluetooth. Fitting this into the three-tier architecture allows for complex processing in the system without limiting the battery lifetime of the portable and wearable parts.In the currently-implemented example, photos captured by the wearable device are compared against a database of faces stored on the remote computer. The user subsequently receives information about people around them via their smartphone. More generally, the architecture permits a wide range of intelligent methods for selecting useful cues, based on the user's environment, to be integrated into the system, facilitating the provision of real-time help for memory problems

    Semiometrics: Applying Ontologies across Large-Scale Digital Libraries

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    As large-scale digital libraries become more available and complete, not to mention more numerous, it is clear there is a need for services that can draw together and perform inference calculations on the metadata produced. However, the traditional Relational Database Management System (RDBMS) model, while efficiently constructed and optimised for many business structures, does not necessarily cope well with issues of concurrent data updates and retrieval at the scale of hundreds of thousands of papers. At the same time the growth of RDF and the increasing interest in Semantic Web technologies perhaps begins to present a viable alternative at a scalable, practical level. This paper considers a specific application of large-scale metadata analysis and conducts scalability tests using real-world data. It concludes that RDF technologies are both a scalable and performance-realistic alternative to traditional RDBMS approaches. It also shows that for relationship-based queries on large-scale metadata stores, RDF technologies can significantly out-perform traditional RDBMS approaches by allowing both retrieval and updating of data in a timely manner

    Haematozoans from deep water fishes trawled off the Cape Verde Islands and over the Porcupine Seabight, with a revision of species within the genus 'Desseria' (Adeleorina: Haemogregarinidae)

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    Archived blood smears from 32 of 113 fishes in 18 families and 12 orders, trawled from deep North Atlantic waters off the Cape Verde Islands in 1999 and over the Porcupine Seabight in 2001 were found to harbour haematozoans. These included four species of haemogregarines (Adeleorina, Haemogregarinidae) and a species of trypanosome (Trypanosomatina, Trypanosomatidae) located in Porcupine Seabight fishes. Also present were Haemohormidium-like structures of uncertain status found in samples from this location and from the Cape Verde Islands. Although material was limited, two of the haemogregarines were provisionally named Desseria harriottae sp. n. from Harriotta raleighana Goode et Bean (Chimaeriformes, Rhinochimaeridae), and Haemogregarina bathysauri sp. n. from Bathysaurus ferox Günther (Aulopiformes, Bathysauridae). The two remaining haemogregarines were identified as Desseria marshalllairdi (Khan, Threlfall et Whitty, 1992) from Halosauropsis macrochir (Günther) (Notacanthiformes, Halosauridae), and Haemogregarina michaeljohnstoni (Davies et Merrett, 2000) from Cataetyx laticeps Koefoed (Ophidiformes, Bythitidae). The name H. michaeljohnstoni was proposed to replace Haemogregarinajohnstoni Davies et Merrett, 2000 from C. laticeps and to avoid confusion with Hepatozoon johnstoni (Mackerras, 1961) Smith, 1996 from varanid lizards, originally named Haemogregarina johnstoni Mackerras, 1961. The trypanosome formed a mixed parasitaemia with D. harriottae in H. raleighana and was provisionally named Trypanosoma harriottae sp. n. No blood parasites had been described previously from cartilaginous fishes of the Holocephali, making the finds in H. raleighana unique. Haemohormidium-like structures were located in erythrocytes in one fish, Coryphaenoides armatus (Hector), among the Cape Verde Islands samples and in 12 species of fishes from the Porcupine Seabight; all these hosts were bony fishes. Finally, the haemogregarine species listed in the genus Desseria Siddall, 1995 were reassessed. Of the original list of 41 species, 30 were retained and 5 species added, including D. harriottae, so that the genus now contains 35 species

    Combustion and Society: A Fire-Centred History of Energy Use

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    Fire is a force that links everyday human activities to some of the most powerful energetic movements of the Earth. Drawing together the energy-centred social theory of Georges Bataille, the fire-centred environmental history of Stephen Pyne, and the work of a number of ‘pyrotechnology’ scholars, the paper proposes that the generalized study of combustion is a key to contextualizing human energetic practices within a broader ‘economy’ of terrestrial and cosmic energy flows. We examine the relatively recent turn towards fossil-fuelled ‘internal combustion’ in the light of a much longer human history of ‘broadcast’ burning of vegetation and of artisanal pyrotechnologies – the use of heat to transform diverse materials. A combustion-centred analysis, it is argued, brings human collective life into closer contact with the geochemical and geologic conditions of earthly existence, while also pointing to the significance of explorative, experimental and even playful dispositions towards energy and matter. © 2014, SAGE Publications. All rights reserved

    Detection of Cognitive Features from Web Resources in Support of Cultural Modeling and Analysis

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    The World Wide Web serves as a valuable source of culture-relevant information, which can be used to support cultural modeling and analysis activities. Part of the challenge in exploiting the Web as a source of culture-relevant information relates to the need to detect and extract information about beliefs, attitudes, and values from a variety of different resources. The Web thus features a rich variety of information resources, and these are seldom categorized with respect to the dimensions in which cultural analysts are interested. Exploiting the Web as a source of culture-relevant information therefore requires techniques and approaches that enable cultural analysts to extract relevant information and organize extracted content in various ways. In this paper, we outline an approach to assist cultural analysts in the extraction and organization of relevant information. We show techniques that can be used to extract information about the attitudes, beliefs, and values of individuals, and how this data can, in turn, be used to support cultural modeling and analysis

    The Significance of Squid, Whale and Other Remains From the Stomachs of Bottom-Living Deep-Sea Fish

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    Twenty-four out of 240 fishes caught by bottom lines at 366–3333 m had something in their stomachs. Stomach contents included parts of cephalopods, fish, cetaceans and bottom-living invertebrates, thin rubber sheet and terrestrial mammal bones. The material provides evidence that four species of cephalopod are at least partially demersal and suggests a means by which the tapeworm Phyllobothrium could pass from its secondary to its primary host. During the five biological cruises of R.R.S. ‘Discovery’ between 1967 and 1971 a total of 31 bottom lines with 1483 hooks were fished in depths of water between 366 and 3333 m. The stomachs of the 240 fish caught were examined and 216 (90%) proved to be empty. The high incidence of empty stomachs is thought to be due to frequent loss of food during the ascent from great depths and accounts for our poor knowledge of the feeding habits of demersal fish living at depths exceeding 400 m. The present collection of food from 25 stomachs (24 from ‘Discovery’ collections and one from a fish caught by Mr G. R. Forster from R. V. ‘Sarsia’) of fish belonging to 11 species (Table 1) probably gives little indication of the usual diet of the fish concerned, but its nature prompts some useful speculation and the rarity of such observations justifies placing them on record (Bigelow & Schroeder, 1948; Marshall, 1954). All the fish were caught on lines which lay on the bottom for several hours and it is our firm belief that they were hooked while on or very near the bottom
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