1,258 research outputs found
Timed Analysis of Security Protocols
We propose a method for engineering security protocols that are aware of
timing aspects. We study a simplified version of the well-known Needham
Schroeder protocol and the complete Yahalom protocol, where timing information
allows the study of different attack scenarios. We model check the protocols
using UPPAAL. Further, a taxonomy is obtained by studying and categorising
protocols from the well known Clark Jacob library and the Security Protocol
Open Repository (SPORE) library. Finally, we present some new challenges and
threats that arise when considering time in the analysis, by providing a novel
protocol that uses time challenges and exposing a timing attack over an
implementation of an existing security protocol
Information activity in serious leisure
Background. In the past decade, scholars of information science have started to conduct research on information behaviour in serious leisure. Presently, these studies lack common concepts and terms and empirical discoveries are not easy to assemble into theory.
Aim. This conceptual and methodological paper surveys the aforementioned research area and introduces Anders Hektor’s model of information behaviour in conjunction with the serious leisure perspective as a means to systematically study information behaviour in serious leisure.
Method. Three methods are employed. The first is a selective literature review and intellectual history of research into information behaviour in serious leisure. The second is a conceptual analysis of Hektor’s model that relates its key features to the serious leisure perspective. The third consists of a deductive audit of three forms of serious leisure (the liberal arts hobby, amateur musicianship, and the hobby of running), utilizing the frameworks, concepts, and terms outlined in the paper.
Results. Studies of information behaviour in serious leisure have increased and deepened in the past decade, largely through ideographic case studies. Hektor’s model of information behaviour, with its locus in everyday life and precise delineation of eight information activities, can complement such research designs. A deductive audit guided by Hektor’s model illuminated information activities within the three forms of serious leisure and enabled comparative observations.
Conclusions. When combined with the serious leisure perspective, Hektor’s model enables research that is comparative and more precise. However, the extent to which this model captures physical or embodied information should be further examined
Two methodologies for physical penetration testing using social engineering
Penetration tests on IT systems are sometimes coupled with physical penetration tests and social engineering. In physical penetration tests where social engineering is allowed, the penetration tester directly interacts with the employees. These interactions are usually based on deception and if not done properly can upset the employees, violate their privacy or damage their trust toward the organization and might lead to law suits and loss of productivity. We propose two methodologies for performing a physical penetration test where the goal is to gain an asset using social engineering. These methodologies aim to reduce the impact of the penetration test on the employees. The methodologies have been validated by a set of penetration tests performed over a period of two year
The treatment of primary tumors of the femur with chemotherapy (if indicated), resection and reconstruction with an endoprosthesis
The treatment protocol of 15 patients with a primary tumor of the femur, including osteosarcoma, malignant fibrous histiocytoma and chondrosar-coma is presented. All patients had been selected for resection and reconstruction with an endoprosthesis. An endoprothesis was implanted in 12 patients. \ud
The results of this type of treatment appear to be satisfactory. In eight osteosarcoma cases resection and reconstruction with an endoprosthesis combined with preoperative and postoperative chemotherapy, according to Rosen, were performed. Follow-up in all 15 patients, varying from 1.4 to 6.0 years, showed no evidence of disease in 12 patients. Three patients had died. Function of the involved leg was satisfactory in most cases. \ud
The advantage and disadvantages of the use of an endoprosthesis are discussed as well as complications in this series of patients
Demonstrating Advantages of Neuromorphic Computation: A Pilot Study
Neuromorphic devices represent an attempt to mimic aspects of the brain's
architecture and dynamics with the aim of replicating its hallmark functional
capabilities in terms of computational power, robust learning and energy
efficiency. We employ a single-chip prototype of the BrainScaleS 2 neuromorphic
system to implement a proof-of-concept demonstration of reward-modulated
spike-timing-dependent plasticity in a spiking network that learns to play the
Pong video game by smooth pursuit. This system combines an electronic
mixed-signal substrate for emulating neuron and synapse dynamics with an
embedded digital processor for on-chip learning, which in this work also serves
to simulate the virtual environment and learning agent. The analog emulation of
neuronal membrane dynamics enables a 1000-fold acceleration with respect to
biological real-time, with the entire chip operating on a power budget of 57mW.
Compared to an equivalent simulation using state-of-the-art software, the
on-chip emulation is at least one order of magnitude faster and three orders of
magnitude more energy-efficient. We demonstrate how on-chip learning can
mitigate the effects of fixed-pattern noise, which is unavoidable in analog
substrates, while making use of temporal variability for action exploration.
Learning compensates imperfections of the physical substrate, as manifested in
neuronal parameter variability, by adapting synaptic weights to match
respective excitability of individual neurons.Comment: Added measurements with noise in NEST simulation, add notice about
journal publication. Frontiers in Neuromorphic Engineering (2019
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Fandom, food, and folksonomies: The methodological realities of studying fun life-contexts
As Library and Information Science research has evolved, new domains of interest have shaped the field, and with them comes a need to question the appropriateness of applying traditional methodologies to these new domains. This panel focuses on the methodological realities of studying fun life-contexts and will address how researching a new domain comes with challenges and opportunities. The group of scholars on this panel all share an appreciation for identifying and exploring the unique information experiences within fun life-contexts, and engage with a variety of subfields, including information behavior, information organization, embodied information, and fan communities. This interactive panel will consist of five short presentations from each of the panelists and a moderated Q&A led by moderator, Jenna Hartel. The panelists each share some examples of their recent work studying fun life-contexts, reflect on their experience researching in a new domain, and develop themes and questions that should be addressed in future work
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