104,627 research outputs found
Leveraging the Grid to Provide a Global Platform for Ubiquitous Computing Research
The requirement for distributed systems support for Ubicomp has led to the development of numerous platforms, each addressing a subset of the overall requirements of ubiquitous systems. In contrast, many other scientific disciplines have embraced the vision of a global distributed computing platform, i.e. the Grid. We believe that the Grid has the potential to evolve into an ideal platform for building ubiquitous computing applications. In this paper we explore in detail the areas of synergy between Grid computing and ubiquitous computing and highlight a series of research challenges in this space
Mobile Computing in Physics Analysis - An Indicator for eScience
This paper presents the design and implementation of a Grid-enabled physics
analysis environment for handheld and other resource-limited computing devices
as one example of the use of mobile devices in eScience. Handheld devices offer
great potential because they provide ubiquitous access to data and
round-the-clock connectivity over wireless links. Our solution aims to provide
users of handheld devices the capability to launch heavy computational tasks on
computational and data Grids, monitor the jobs status during execution, and
retrieve results after job completion. Users carry their jobs on their handheld
devices in the form of executables (and associated libraries). Users can
transparently view the status of their jobs and get back their outputs without
having to know where they are being executed. In this way, our system is able
to act as a high-throughput computing environment where devices ranging from
powerful desktop machines to small handhelds can employ the power of the Grid.
The results shown in this paper are readily applicable to the wider eScience
community.Comment: 8 pages, 7 figures. Presented at the 3rd Int Conf on Mobile Computing
& Ubiquitous Networking (ICMU06. London October 200
High-resolution models of solar granulation: the 2D case
Using grid refinement, we have simulated solar granulation in 2D. The refined
region measures 1.97*2.58 Mm (vertical*horizontal). Grid spacing there is
1.82*2.84 km. The downflows exhibit strong Kelvin-Helmholtz instabilities.
Below the photosphere, acoustic pulses are generated. They proceed laterally
(in some cases distances of at least the size of our refined domain) and may be
enhanced when transversing downflows) as well as upwards where, in the
photosphere they contribute significantly to 'turbulence' (velocity gradients,
etc.) The acoustic pulses are ubiquitous in that at any time several of them
are seen in our high-resolution domain. Their possible contributions to p-mode
excitation or heating of the chromosphere needs to be investigated
A Graph-Based Approach to Address Trust and Reputation in Ubiquitous Networks
The increasing popularity of virtual computing environments such as Cloud and Grid computing is helping to drive the realization of ubiquitous and pervasive computing. However, as computing becomes more entrenched in everyday life, the concepts of trust and risk become increasingly important. In this paper, we propose a new graph-based theoretical approach to address trust and reputation in complex ubiquitous networks. We formulate trust as a function of quality of a task and time required to authenticate agent-to-agent relationship based on the Zero-Common Knowledge (ZCK) authentication scheme. This initial representation applies a graph theory concept, accompanied by a mathematical formulation of trust metrics. The approach we propose increases awareness and trustworthiness to agents based on the values estimated for each requested task, we conclude by stating our plans for future work in this area
Multipole-Preserving Quadratures for Discretization of Functions in Real-Space Electronic Structure Calculations
Discretizing an analytic function on a uniform real-space grid is often done
via a straightforward collocation method. This is ubiquitous in all areas of
computational physics and quantum chemistry. An example in Density Functional
Theory (DFT) is given by the external potential or the pseudo-potential
describing the interaction between ions and electrons. The accuracy of the
collocation method used is therefore very important for the reliability of
subsequent treatments like self-consistent field solutions of the electronic
structure problems. By construction, the collocation method introduces
numerical artifacts typical of real-space treatments, like the so-called
egg-box error, that may spoil the numerical stability of the description when
the real-space grid is too coarse. As the external potential is an input of the
problem, even a highly precise computational treatment cannot cope this
inconvenience. We present in this paper a new quadrature scheme that is able to
exactly preserve the moments of a given analytic function even for large grid
spacings, while reconciling with the traditional collocation method when the
grid spacing is small enough. In the context of real-space electronic structure
calculations, we show that this method improves considerably the stability of
the results for large grid spacings, opening the path towards reliable
low-accuracy DFT calculations with reduced number of degrees of freedom.Comment: 20 pages, 7 figure
Ubiquitous Sensor Networks and Its Application
Ubiquitous sensor networks and its application are emerging rapidly as an exciting new paradigm to provide reliable and comfortable life services. The ever-growing ubiquitous sensor networks and its application will provide an intelligent and ubiquitous communication and network technology for tomorrow. That is, the UCMA have emerged rapidly as an exciting new paradigm that includes ubiquitous, grid, and peer-to-peer computing to provide computing and communication services at anytime and anywhere. In order to realize the advantages of such services, it is important that intelligent systems be suitable for UCMA
Secure and privacy-aware proxy mobile IPv6 protocol for vehicle-to-grid networks
Vehicle-to-Grid (V2G) networks have emerged as a new communication paradigm between Electric Vehicles (EVs) and the Smart Grid (SG). In order to ensure seamless communications between mobile EVs and the electric vehicle supply equipment, the support of ubiquitous and transparent mobile IP communications is essential in V2G networks. However, enabling mobile IP communications raises real concerns about the possibility of tracking the locations of connected EVs through their mobile IP addresses. In this paper, we employ certificate-less public key cryptography in synergy with the restrictive partially blind signature technique to construct a secure and privacy-aware proxy mobile IPv6 (SP-PMIPv6) protocol for V2G networks. SP-PMIPv6 achieves low authentication latency while protecting the identity and location privacy of the mobile EV. We evaluate the SP-PMIPv6 protocol in terms of its authentication overhead and the information-theoretic uncertainty derived by the mutual information metric to show the high level of achieved anonymity
- …