11,793 research outputs found
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Smart labs and social practice: social tools for pervasive laboratory workspaces: a position paper
The emergence of pervasive and ubiquitous computing stimulates a view of future work environments where sharing of information, data and knowledge is easy and commonplace, particularly in highly interactive settings. Much of the work in this area focuses on tool development to support activities such as data collection, data recording and sharing, and so on. We are interested in this kind of technical development, which is both challenging and essential for science communities. But we are also interested in a broader interpretation of knowledge sharing and the human/social side of tools we develop to support this. We are keen to know more about how groups of different kinds of scientists can make their work understandable and shareable with each other in a multidisciplinary setting. This is a complex task because boundaries and barriers can emerge between disciplines engendered by differences in discourses and practices, which may not easily translate into other discipline areas. In the worst case, there may be some hostility between disciplines, or at least doubt and scepticism. Nevertheless, sharing approaches to research, research expertise, data and methods across disciplines can be a very fruitful exercise, and encouragement to engage in this activity is particularly pertinent in the digital era. Issues of privacy and security are also key aspects – knowing when and how to release data or information to other groups is crucial to providing a safe environment for people to work, and there are several sensitivities to be explored here.
In this paper we describe an evolving situation that captures many of these issues, which we aim to track longitudinally
Mass-Market Receiver for Static Positioning: Tests and Statistical Analyses
Nowadays, there are several low cost GPS receivers able to provide both pseudorange and carrier phase measurements in the L1band, that allow to have good realtime performances in outdoor condition. The present paper describes a set of dedicated tests in order to evaluate the positioning accuracy in static conditions. The quality of the pseudorange and the carrier phase measurements let hope for interesting results. The use of such kind of receiver could be extended to a large number of professional applications, like engineering fields: survey, georeferencing, monitoring, cadastral mapping and cadastral road. In this work, the receivers performance is verified considering a single frequency solution trying to fix the phase ambiguity, when possible. Different solutions are defined: code, float and fix solutions. In order to solve the phase ambiguities different methods are considered. Each test performed is statistically analyzed, highlighting the effects of different factors on precision and accurac
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A hydrogen framework for the East Midlands
Profiles capabilities in midlands-based organisations in hydrogen and fuel cell technologies as a rationale for support of a Midlands hydrogen cluster
Ancillary service provision by demand side management : a real-time power hardware-in-the-loop co-simulation demonstration
The role of demand side management in providing ancillary services to the network is an active topic of research. However, their implementation is limited due to lack of practical demonstrations and tests that can rigorously quantify their ability to support the grid’s integrity. In this paper, provision of time critical frequency control ancillary service is demonstrated by means of integrating PowerMatcher, a well discussed demand side management mechanism in literature, with real-time power hardware. The co-simulation platform enables testing of demand side management techniques to provide ancillary services
Kestrel: Job Distribution and Scheduling using XMPP
A new distributed computing framework, named Kestrel, for Many-Task Computing (MTC) applications and implementing Virtual Organization Clusters (VOCs) is proposed. Kestrel is a lightweight, highly available system based on the Extensible Messaging and Presence Protocol (XMPP), and has been developed to explore XMPP-based techniques for improving MTC and VOC tolerance to faults due to scaling and intermittently connected heterogeneous resources. Kestrel provides a VOC with a special purpose scheduler for VOCs which can provide better scalability under certain workload assumptions, namely CPU bound processes and bag-of-task applications. Experimental results have shown that Kestrel is capable of operating a VOC of at least 1600 worker nodes with all nodes visible to the scheduler at once. When using multiple sites located in both North America and Europe, the latencies introduced to the round trip time of messages were on the order of 0.3 seconds. To offset the overhead of XMPP processing, a task execution time of 2 seconds is sufficient for a pool of 900 workers on a single site to operate at near 100% use. Requiring tasks that take on the order of 30 seconds to a minute to execute would compensate for increased latency during job dispatch across multiple sites. Kestrel\u27s architecture is rooted in pilot job frameworks heavily used in Grid computing, it is also modeled after the use of IRC by botnets to communicate between compromised machines and command and control servers. For Kestrel, the extensibility of XMPP has allowed development of protocols for identifying manager nodes, discovering the capabilities of worker agents, and for distributing tasks. The presence notifications provided by XMPP allow Kestrel to monitor the global state of the pool and to perform task dispatching based on worker availability. In this work it is argued that XMPP is by design a very good fit for cloud computing frameworks. It offers scalability, federation between servers and some autonomicity of the agents. During the summer of 2010, Kestrel was used and modified based on feedback from the STAR group at Brookhaven National Laboratories. STAR provided a virtual machine image with applications for simulating proton collisions using PYTHIA and GEANT3. A Kestrel-based virtual organization cluster, created on top of Clemson University\u27s Palmetto cluster, was able to provide over 400,000 CPU hours of computation over the course of a month using an average of 800 virtual machine instances every day, generating nearly seven terabytes of data and the largest PYTHIA production run that STAR ever achieved. Several architectural issues were encountered during the course of the experiment and were resolved by moving from the original JSON protocols used by Kestrel to native XMPP equivalents that offered better message delivery confirmation and integration with existing tools
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Application of Advanced Early Warning Systems with Adaptive Protection
This project developed and field-tested two methods of Adaptive Protection systems utilizing synchrophasor data. One method detects conditions of system stress that can lead to unintended relay operation, and initiates a supervisory signal to modify relay response in real time to avoid false trips. The second method detects the possibility of false trips of impedance relays as stable system swings “encroach” on the relays’ impedance zones, and produces an early warning so that relay engineers can re-evaluate relay settings. In addition, real-time synchrophasor data produced by this project was used to develop advanced visualization techniques for display of synchrophasor data to utility operators and engineers
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