Search results for "clou"
showing 10 items of 830 documents
Theoretical Investigations of the Wet Deposition of Atmospheric Pollutants
2007
SHOCK-CLOUD INTERACTION AND PARTICLE ACCELERATION IN THE SOUTHWESTERN LIMB OF SN 1006
2014
The supernova remnant SN 1006 is a powerful source of high-energy particles and evolves in a relatively tenuous and uniform environment despite interacting with an atomic cloud in its northwestern limb. The X-ray image of SN 1006 reveals an indentation in the southwestern part of the shock front and the H I maps show an isolated (southwestern) cloud, having the same velocity as the northwestern cloud, whose morphology fits perfectly in the indentation. We performed spatially resolved spectral analysis of a set of small regions in the southwestern nonthermal limb and studied the deep X-ray spectra obtained within the XMM-Newton SN 1006 Large Program. We also analyzed archive H I data, obtain…
Robustified smoothing for enhancement of thermal image sequences affected by clouds
2015
Obtaining radiometric surface temperature information with both high acquisition rate and high spatial resolution is still not possible through a single sensor. However, in several earth observation applications, the fusion of data acquired by different sensors is a viable solution for so called image sharpening. A related issue is the presence of clouds, which may impair the performance of the data fusion algorithms. In this paper we propose a robustified setup for the sharpening of thermal images in a non real-time scenario, capable to deal with missing thermal data due to cloudy pixels, and robust with respect to cloud mask misclassifications. The effectiveness of the presented technique…
Using Cloud Computing to Implement a Security Overlay Network
2012
This article proposes and analyzes a general cloud-based security overlay network that can be used as a transparent overlay network to provide services such as intrusion detection systems, antivirus and antispam software, and distributed denial-of-service prevention. The authors analyze each of these in-cloud security services in terms of resiliency, effectiveness, performance, flexibility, control, and cost.
Comparative analysis of architectures for monitoring cloud computing infrastructures
2015
The lack of control over the cloud resources is one of the main disadvantages associated to cloud computing. The design of efficient architectures for monitoring such resources can help to overcome this problem. This contribution describes a complete set of architectures for monitoring cloud computing infrastructures, and provides a taxonomy of them. The architectures are described in detail, compared among them, and analysed in terms of performance, scalability, usage of resources, and security capabilities. The architectures have been implemented in real world settings and empirically validated against a real cloud computing infrastructure based on OpenStack. More than 1000 virtual machin…
Distributing Storage in Cloud Environments
2013
Cloud computing has a major impact on today's IT strategies. Outsourcing applications from IT departments to the cloud relieves users from building big infrastructures as well as from building the corresponding expertise, and allows them to focus on their main competences and businesses. One of the main hurdles of cloud computing is that not only the application, but also the data has to be moved to the cloud. Networking speed severely limits the amount of data that can travel between the cloud and the user, between different sites of the same cloud provider, or indeed between different cloud providers. It is therefore important to keep applications near the data itself. This paper investig…
Cloud Computing Adoption Factors and Processes for Enterprises - A Systematic Literature Review
2014
Cloud computing has received an increasing interest from enterprises since its inception. With its innovative Information Technology (IT) services delivery model, cloud computing could add technical and strategic business values to enterprises. However, it poses highly concerning, internal and external, issues. This paper presents a systematic literature review to explore cloud computing adoption processes in the context of enterprise users and the factors that affect these processes. This is achieved by reviewing 37 articles published about cloud computing adoption. Using the grounded theory approach, articles are classified into eight main categories: internal, external, evaluation, proof…
A Literature Review on Cloud Computing Adoption Issues in Enterprises
2014
Part 3: Creating Value through Applications; International audience; Cloud computing has received increasing interest from enterprises since its inception. With its innovative information technology (IT) services delivery model, cloud computing could add technical and strategic business value to enterprises. However, cloud computing poses highly concerning internal (e.g., Top management and experience) and external issues (e.g., regulations and standards). This paper presents a systematic literature review to explore the current key issues related to cloud computing adoption. This is achieved by reviewing 51 articles published about cloud computing adoption. Using the grounded theory approa…
An Overview of Cloud Computing Adoption Challenges in the Norwegian Context
2014
Cloud computing is dominating European countries' Information and Communication Technology (ICT) agenda. Although the European cloud market is mostly mature, there are still challenges to overcome. Norway is one of the European countries facing such challenges, despite it is a developed country in terms of quality of life and ICT development. This paper identifies the current state of cloud computing adoption challenges in Europe in general and Norway in specific, and the way they are addressed. This is achieved through analyzing research articles, reports published by consulting companies and official bodies, official online news articles, and documents published by official authorities. T…