8,563 research outputs found

    The Ethics and Impact of Digital Immortality

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    The concept of digital immortality has emerged over the past decade and is defined here as the continuation of an active or passive digital presence after death. Advances in knowledge management, machine to machine communication, data mining and artificial intelligence are now making a more active presence after death possible. This paper examines the research and literature around active digital immortality and explores the emotional, social, financial, and business impact of active digital immortality on relations, friends, colleagues and institutions. The issue of digital immortality also raises issues about the legal implications of a possible autonomous presence that reaches beyond mortal existence, and this will also be investigated. The final section of the paper questions whether digital immortality is really a concern and reflects on the assumptions about it in relation to neoliberal capitalism. It suggests that digital immortality may in fact merely be a clever ruse which in fact is likely to have little, if any legal impact despite media assumptions and hyperbole

    Learning at the Interstices; Locating Practical Philosophies for Understanding Physical/virtual Inter-spaces

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    Virtual worlds are relatively recent developments, and so it is tempting to believe that they need to be understood through newly developed theories and philosophies. However, humans have long thought about the nature of reality and what it means to be “real.” This paper examines the three persistent philosophical concepts of Metaxis, Liminality and Space that have evolved across more than 2000 years of meditation, contemplation and reflection. Our particular focus here is on the nature of the interface between the virtual and the physical: at the interstices, and how the nature of transactions and transitions across those interfaces may impact upon learning. This may, at first, appear to be an esoteric pursuit, but we ground our arguments in primary and secondary data from research studies in higher education

    Concrete Mix Design Using Double Coating Method

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    Considerable study, particularly in the last twenty to thirty years, has led to a much better understanding of the structure and behaviour of concrete.  This has accompanied by an improved and more sophisticated technology and the product now mad, in its variety of forms, is much more capable of satisfying the huge increasing demands required of it.  Because the behaviour of both fresh and hardened concrete is significantly related to their composition it should be possible, at least principle, to choose better ingredients with suitable proportion to gain the required satisfaction.   A good mix design for concrete mixtures is considered as a milestone for the construction of any concrete member or structure meets economical, service and durability requirements, as well as safety and efficiency throughout its life cycle.  Currently, there are many international methods locally approved for mix designs, such as: the ACI  method and the BS method, which are widely used in Libya at research centers, universities, and concrete batch plants as well as pre-cast concrete manufacturing plants (e.g.: pre-stressed concrete beams, concrete columns and slabs, etc.).  These methods depend on certain equations and graphs based on mathematical analysis of results obtained from previous field experience.  Generally speaking, mix design methods give some indication to the designer to validate and adjust them via experimental mixes in the local laboratories in order to check the variables related to the characteristics and properties of the local materials and the surrounding environment conditions.  This paper illustrates the steps used for mix design using the double coating method, which is currently used in some research centres in Poland and was recently applied in the laboratories of the Civil Engineering Department in the University of Tripoli in Libya.  Results obtained by this method using the local materials subject to local environmental conditions are presented and discussed

    ÆGIS: Shielding Vulnerable Smart Contracts Against Attacks

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    In recent years, smart contracts have suffered major exploits, cost- ing millions of dollars. Unlike traditional programs, smart contracts are deployed on a blockchain. As such, they cannot be modified once deployed. Though various tools have been proposed to detect vulnerable smart contracts, the majority fails to protect vulnera- ble contracts that have already been deployed on the blockchain. Only very few solutions have been proposed so far to tackle the issue of post-deployment. However, these solutions suffer from low precision and are not generic enough to prevent any type of attack. In this work, we introduce ÆGIS, a dynamic analysis tool that protects smart contracts from being exploited during runtime. Its capability of detecting new vulnerabilities can easily be extended through so-called attack patterns. These patterns are written in a domain-specific language that is tailored to the execution model of Ethereum smart contracts. The language enables the description of malicious control and data flows. In addition, we propose a novel mechanism to streamline and speed up the process of managing attack patterns. Patterns are voted upon and stored via a smart contract, thus leveraging the benefits of tamper-resistance and transparency provided by the blockchain. We compare ÆGIS to current state-of-the-art tools and demonstrate that our solution achieves higher precision in detecting attacks. Finally, we perform a large-scale analysis on the first 4.5 million blocks of the Ethereum blockchain, thereby confirming the occurrences of well reported and yet unreported attacks in the wild

    Evaluating a Second Life PBL Demonstrator Project: What Can We Learn?

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    This article reports the findings of a demonstrator project to evaluate how effectively Immersive Virtual Worlds (IVWs) could support Problem-based Learning. The project designed, created and evaluated eight scenarios within Second Life (SL) for undergraduate courses in health care management and paramedic training. Evaluation was primarily qualitative, using illuminative evaluation which provided multiple perspectives through interviews, focus groups and questionnaires with designers, facilitators, learning technologists and students. Results showed that SL provided a rich, engaging environment which enhanced authenticity of the scenarios, though there were issues of access and usability. The article concludes by drawing together the lessons learned which will inform educators who seek to design and develop learning scenarios in this medium

    UPC++: A high-performance communication framework for asynchronous computation

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    UPC++ is a C++ library that supports high-performance computation via an asynchronous communication framework. This paper describes a new incarnation that differs substantially from its predecessor, and we discuss the reasons for our design decisions. We present new design features, including future-based asynchrony management, distributed objects, and generalized Remote Procedure Call (RPC). We show microbenchmark performance results demonstrating that one-sided Remote Memory Access (RMA) in UPC++ is competitive with MPI-3 RMA; on a Cray XC40 UPC++ delivers up to a 25% improvement in the latency of blocking RMA put, and up to a 33% bandwidth improvement in an RMA throughput test. We showcase the benefits of UPC++ with irregular applications through a pair of application motifs, a distributed hash table and a sparse solver component. Our distributed hash table in UPC++ delivers near-linear weak scaling up to 34816 cores of a Cray XC40. Our UPC++ implementation of the sparse solver component shows robust strong scaling up to 2048 cores, where it outperforms variants communicating using MPI by up to 3.1x. UPC++ encourages the use of aggressive asynchrony in low-overhead RMA and RPC, improving programmer productivity and delivering high performance in irregular applications

    Teaching Archaeological Pragmatism through Problem-Based Learning

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    Openspritzer: an open hardware pressure ejection system for reliably delivering picolitre volumes

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    The ability to reliably and precisely deliver picolitre volumes is an important component of biological research. Here we describe a high-performance, low-cost, open hardware pressure ejection system (Openspritzer), which can be constructed from off the shelf components. The device is capable of delivering minute doses of reagents to a wide range of biological and chemical systems. In this work, we characterise the performance of the device and compare it to a popular commercial system using twophoton fluorescence microscopy. We found that Openspritzer provides the same level of control over delivered reagent dose as the commercial system. Next, we demonstrate the utility of Openspritzer in a series of standard neurobiological applications. First, we used Openspritzer to deliver precise amounts of reagents to hippocampal neurons to elicit time- and dose-precise responses on neuronal voltage. Second, we used Openspritzer to deliver infectious viral and bacterial agents to living tissue. This included viral transfection of hippocampal interneurons with channelrhodopsin for the optogenetic manipulation of hippocampal circuitry with light. We anticipate that due to its high performance and low cost Openspritzer will be of interest to a broad range of researchers working in the life and physical sciences
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