155,366 research outputs found
States' Roles in Shaping High Performance Health Systems
Analyzes results from the State Health Policies Aimed at Promoting Excellent Systems survey and a review of current research on efforts to improve state healthcare systems, with a focus on coverage; quality, safety, and value; and infrastructure
Proceedings of the International Workshop on: methods and tools for water-related adaptation to climate change and climate proofing
The workshop fits in the National Water Plan of the Netherlands’ government of which the international chapter includes the strengthening of cooperation with other delta countries, including Indonesia, Vietnam and Bangladesh and is part of the work plan of the Cooperative Programme on Water and Climate, a Netherlands’ sponsored programme with the objective to improve knowledge and capacity on the relation between water and climate change especially in developing countries and countries in transition
Parallel memetic algorithms for independent job scheduling in computational grids
In this chapter we present parallel implementations of Memetic Algorithms (MAs) for the problem of scheduling independent jobs in computational grids. The problem of scheduling in computational grids is known for its high demanding computational time. In this work we exploit the intrinsic parallel nature of MAs as well as the fact that computational grids offer large amount of resources, a part of which could be used to compute the efficient allocation of jobs to grid resources.
The parallel models exploited in this work for MAs include both fine-grained and coarse-grained parallelization and their hybridization. The resulting schedulers have been tested through different grid scenarios generated by a grid simulator to match different possible configurations of computational grids in terms of size (number of jobs and resources) and computational characteristics of resources. All in all, the result of this work showed that Parallel MAs are very good alternatives in order to match different performance requirement on fast scheduling of jobs to grid resources.Peer ReviewedPostprint (author's final draft
Analysis and Use of Information and Communication Tools in Economics of Climate Change
The use of Information and Communication Technologies (ICT) in the context of climate change is of great importance in the scientific community, but can also play an important role in the policy context. On the one hand, the results achievable for mitigation and adaptation are influencing the policy arena, and on the other hand these instruments represent an opportunity for decision-makers to apply innovative forms of public administration based on stakeholder involvement, which can reduce the existing gap between policy-makers and citizens (Oates, 2003). The paper provides an analysis of the main ICT tools and methods used in climate change economics by means of a questionnaire-based survey and focus group discussion with specific experts in this context. The issues addressed are related with the use and relevance of ICT in the different research area of climate change, the perceived usefulness of these tools, and their importance in the scientific, economic and policy contexts. The main problems and limitations of ICT are investigated, together with their potential role in future research.Climate change, Information and Communication Technologies tools (ICT)
A Tractable Model of the LTE Access Reservation Procedure for Machine-Type Communications
A canonical scenario in Machine-Type Communications (MTC) is the one
featuring a large number of devices, each of them with sporadic traffic. Hence,
the number of served devices in a single LTE cell is not determined by the
available aggregate rate, but rather by the limitations of the LTE access
reservation protocol. Specifically, the limited number of contention preambles
and the limited amount of uplink grants per random access response are crucial
to consider when dimensioning LTE networks for MTC. We propose a low-complexity
model of LTE's access reservation protocol that encompasses these two
limitations and allows us to evaluate the outage probability at click-speed.
The model is based chiefly on closed-form expressions, except for the part with
the feedback impact of retransmissions, which is determined by solving a fixed
point equation. Our model overcomes the incompleteness of the existing models
that are focusing solely on the preamble collisions. A comparison with the
simulated LTE access reservation procedure that follows the 3GPP
specifications, confirms that our model provides an accurate estimation of the
system outage event and the number of supported MTC devices.Comment: Submitted, Revised, to be presented in IEEE Globecom 2015; v3: fixed
error in eq. (4
A robust digital image watermarking using repetition codes against common attacks
Digital watermarking is hiding the information inside a digital media to protect for
such documents against malicious intentions to change such documents or even
claim the rights of such documents. Currently the capability of repetition codes on
various attacks in not sufficiently studied. In this project, a robust frequency domain
watermarking scheme has been implemented using Discrete Cosine Transform
(DCT). The idea of this scheme is to embed an encoded watermark using repetition
code (3, 1) inside the cover image pixels based on Discrete Cosine Transform (DCT)
embedding technique. The proposed methods have undergone several simulation
attacks tests in order to check up and compare their robustness against various
attacks, like salt and pepper, speckle, compress, Gaussian, image contrast, resizing
and cropping attack. The robustness of the watermarking scheme has been calculated
using Peak Signal-To-Noise Ratio (PSNR), Mean Squared Error (MSE) and
Normalized Correlations (NC). In our experiments, the results show that the
robustness of a watermark with repetition codes is much better than without
repetition code
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