2,015 research outputs found
Intelligent Management and Efficient Operation of Big Data
This chapter details how Big Data can be used and implemented in networking
and computing infrastructures. Specifically, it addresses three main aspects:
the timely extraction of relevant knowledge from heterogeneous, and very often
unstructured large data sources, the enhancement on the performance of
processing and networking (cloud) infrastructures that are the most important
foundational pillars of Big Data applications or services, and novel ways to
efficiently manage network infrastructures with high-level composed policies
for supporting the transmission of large amounts of data with distinct
requisites (video vs. non-video). A case study involving an intelligent
management solution to route data traffic with diverse requirements in a wide
area Internet Exchange Point is presented, discussed in the context of Big
Data, and evaluated.Comment: In book Handbook of Research on Trends and Future Directions in Big
Data and Web Intelligence, IGI Global, 201
Scalar-gravitational perturbations and quasinormal modes in the five dimensional Schwarzschild black hole
We calculate the quasinormal modes (QNMs) for gravitational perturbations of
the Schwarzschild black hole in the five dimensional (5D) spacetime with a
continued fraction method. For all the types of perturbations
(scalar-gravitational, vector-gravitational, and tensor-gravitational
perturbations), the QNMs associated with l=2, l=3, and l=4 are calculated. Our
numerical results are summarized as follows: (i) The three types of
gravitational perturbations associated with the same angular quantum number l
have a different set of the quasinormal (QN) frequencies; (ii) There is no
purely imaginary frequency mode; (iii) The three types of gravitational
perturbations have the same asymptotic behavior of the QNMs in the limit of the
large imaginary frequencies. In Hawking temperature units these frequencies are
given by log3 + i2pi(n+1/2) as n goes to infinity, where n is the mode number.Comment: 13 pages, 3 figures; to appear in JHE
Decomposing the causes for niche differentiation between species using hypervolumes
Hutchinson's n-dimensional hypervolume concept holds a central role across different fields of ecology and evolution. The question of the amount of hypervolume overlap and differentiation between species is of great interest to understand the processes that drive niche dynamics, competitive interactions and, ultimately, community assembly. A framework is proposed to decompose overall differentiation among hypervolumes into two distinct components: niche shifts and niche contraction/expansion processes. Niche shift corresponds to the replacement of space between the hypervolumes occupied by two species, whereas niche contraction/expansion processes correspond to net differences between the amount of space enclosed by each hypervolume. A procedure to implement non-continuous trait data in the estimation ofn-dimensional hypervolumes is proposed. Hypervolumes were constructed for three Darwin' finches,Geospiza conirostris,Geospiza magnirostris, andGeospiza difficilisusing intraspecific trait data. Results showed that significant niche shifts, not niche contraction, occurred betweenG. conirostrisandG. magnirostrisin Genovesa island, where they live in sympatry. This means thatG. conirostrisoccupied a different niche space and not a reduced space on Genovesa.G. difficiliswas well differentiated from the other two species. The proposed framework allows disentangling different processes underlying niche partitioning between coexisting species. This framework offers novel insights to understand the drivers of niche partitioning strategies among coexisting species.Peer reviewe
Quality perception of PDO beef producers
Food quality from a consumer perspective includes sanitary aspects as well as nutrition, but also taste, aspect, integrity and the particularity of products. But quality at the consumer level can only be achieved if quality is respected throughout the whole chain. An analysis is undertaken using as a case study Portuguese producers of two types of PDO beef. Results, using multivariate data analysis, show that the main attributes for a quality beef at the producers` level are: feeding, finishing, specific quality, age at slaughter, breed and transport. Results also suggest that producers have distinct quality perceptions on PDO beef.quality, beef, Protected Designation of Origin, producers` quality Perception, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Q13, M31,
A Software-Defined Solution for Managing Fog Computing Resources in Sensor Networks
The fast growth of Internet-connected embedded devices demands for new
capabilities at the network edge. These new capabilities are local processing,
fast communications, and resource virtualization. The current work aims to
address the previous capabilities by designing and deploying a new proposal,
which offers on-demand activation of offline IoT fog computing assets via a
Software Defined Networking (SDN) based solution combined with containerization
and sensor virtualization. We present and discuss performance and functional
outcomes from emulated tests made on our proposal. Analysing the performance
results, the system latency has two parts. The first part is about the delay
induced by limitations on the networking resources. The second part of the
system latency is due to the on-demand activation of the required processing
resources, which are initially powered off towards a more sustainable system
operation. In addition, analysing the functional results, when a real IoT
protocol is used, we evidence our proposal viability to be deployed with the
necessary orchestration in distributed scenarios involving embedded devices,
actuators, controllers, and brokers at the network edge.Comment: 8 pages, 14 figures, 2 tables, 16 reference
User expectations for media sharing practices in open display networks
Open Display Networks have the potential to allow many content creators to publish their media to an open-ended set of screen displays. However, this raises the issue of how to match that content to the right displays. In this study, we aim to understand how the perceived utility of particular media sharing scenarios is affected by three independent variables, more specifically: (a) the locativeness of the content being shared; (b) how personal that content is and (c) the scope in which it is being shared. To assess these effects, we composed a set of 24 media sharing scenarios embedded with different treatments of our three independent variables. We then asked 100 participants to express their perception of the relevance of those scenarios. The results suggest a clear preference for scenarios where content is both local and directly related to the person that is publishing it. This is in stark contrast to the types of content that are commonly found in public displays, and confirms the opportunity that open displays networks may represent a new media for self-expression. This novel understanding may inform the design of new publication paradigms that will enable people to share media across the display networks.This research has received funding from FCT under the Carnegie Mellon—Portugal agreement. Project Wesp (Grant CMU-PT/SE/028/2008)
The Barriers of Reporting Wage Theft
Undocumented immigrants are often victims of wage theft. There are many owners who take advantage of this because they know they won\u27t speak up out of the fear of retaliation. However, there have been moments when immigrants have spoken up and received justice. Unfortunately, that\u27s not the case for many as the process to report wage theft can take time and sometimes for nothing. New York City is home to 3.2 million immigrants or 37.1 percent of the population and the undocumented community stands at 5.3 percent.
https://medium.com/@cardoso.jose17/the-barriers-of-reporting-wage-theft-for-undocumented-immigrants-38aafb93721
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