455 research outputs found
OSHI - Open Source Hybrid IP/SDN networking (and its emulation on Mininet and on distributed SDN testbeds)
The introduction of SDN in IP backbones requires the coexistence of regular
IP forwarding and SDN based forwarding. The former is typically applied to best
effort Internet traffic, the latter can be used for different types of advanced
services (VPNs, Virtual Leased Lines, Traffic Engineering...). In this paper we
first introduce the architecture and the services of an "hybrid" IP/SDN
networking scenario. Then we describe the design and implementation of an Open
Source Hybrid IP/SDN (OSHI) node. It combines Quagga for OSPF routing and Open
vSwitch for OpenFlow based switching on Linux. The availability of tools for
experimental validation and performance evaluation of SDN solutions is
fundamental for the evolution of SDN. We provide a set of open source tools
that allow to facilitate the design of hybrid IP/SDN experimental networks,
their deployment on Mininet or on distributed SDN research testbeds and their
test. Finally, using the provided tools, we evaluate key performance aspects of
the proposed solutions. The OSHI development and test environment is available
in a VirtualBox VM image that can be downloaded.Comment: Final version (Last updated August, 2014
Integration of existing IEC 61131-3 systems in an IEC 61499 distributed solution
The IEC 61499 standard allows to model and design
new generation control systems, providing innovative
concepts of software engineering (such as abstraction,
encapsulation, reuse) to the world of control
engineering. The industrial reception of the standard,
however, is still in an early stage, also because its
introduction results in the adoption of a programming
paradigm profoundly different than the widespread IEC
61131-3. This paper presents a method for the
integration of the two standards, that allows to exploit
the benefits of both. The proposed architecture is based
on the parallel execution of both environments that
interact with each other through some specific
interfaces. A test implementation of the architecture is
also presented to demonstrate the feasibility of the
proposed solution
The role of Micro-RNAs in Hepatocellular Carcinoma: From Molecular Biology to Treatment
Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the third leading cause of cancer deaths. microRNAs (miRNAs) are evolutionary conserved small non-coding RNA that negatively regulate gene expression and protein translation. Recent evidences have shown that they are involved in many biological processes, from development and cell-cycle regulation to apoptosis. miRNAs can behave as tumor suppressor or promoter of oncogenesis depending on the cellular function of their targets. Moreover, they are frequently dysregulated in HCC. In this review we summarize the latest findings of miRNAs regulation in HCC and their role as potentially diagnostic and prognostic biomarkers for HCC. We highlight development of miRNAs as potential therapeutic targets for HCC
The identification of pathogens associated with periprosthetic joint infection in two-stage revision
INVESTIGATION ACTIVITY ABOUT A COLLAPSED STEEL STRUCTURE SUBJECTED TO A REAL FIRE, Fire scenarios and structural behaviour of a real steel structure
The paper describes the behaviour ofa real steel structure collapsed under a fire event. 3D structural analyses were performed with SAFIR program (J-M Franssen, 2005). Different modellingare implemented with some fire load models and analyses of thebehaviour of the whole structure. The main purpose of this work was to investigate the failure types of a warehouse structure under fire conditions. Different fire conditions were applied to the steel frame sections, with ISOcurve (ISO EN 834-8:2002) and zone model approach. The analyses show that with unprotected steel sections, horizontal structures are more critical than columns. Trough applying a performance basedapproach,structure has 30 minutes of fire resistance
Reactive postural responses to continuous yaw perturbations in healthy humans: the effect of aging
Maintaining balance stability while turning in a quasi-static stance and/or in dynamic motion requires proper recovery mechanisms to manage sudden center-of-mass displacement. Furthermore, falls during turning are among the main concerns of community-dwelling elderly population. This study investigates the effect of aging on reactive postural responses to continuous yaw perturbations on a cohort of 10 young adults (mean age 28 ± 3 years old) and 10 older adults (mean age 61 ± 4 years old). Subjects underwent external continuous yaw perturbations provided by the RotoBit1D platform. Different conditions of visual feedback (eyes opened and eyes closed) and perturbation intensity, i.e., sinusoidal rotations on the horizontal plane at different frequencies (0.2 Hz and 0.3 Hz), were applied. Kinematics of axial body segments was gathered using three inertial measurement units. In order to measure reactive postural responses, we measured body-absolute and joint absolute rotations, center-of-mass displacement, body sway, and inter-joint coordination. Older adults showed significant reduction in horizontal rotations of body segments and joints, as well as in center-of-mass displacement. Furthermore, older adults manifested a greater variability in reactive postural responses than younger adults. The abnormal reactive postural responses observed in older adults might contribute to the well-known age-related difficulty in dealing with balance control during turning
Hybrid IP/SDN networking: open implementation and experiment management tools
The introduction of SDN in large-scale IP provider networks is still an open
issue and different solutions have been suggested so far. In this paper we
propose a hybrid approach that allows the coexistence of traditional IP routing
with SDN based forwarding within the same provider domain. The solution is
called OSHI - Open Source Hybrid IP/SDN networking as we have fully implemented
it combining and extending Open Source software. We discuss the OSHI system
architecture and the design and implementation of advanced services like Pseudo
Wires and Virtual Switches. In addition, we describe a set of Open Source
management tools for the emulation of the proposed solution using either the
Mininet emulator or distributed physical testbeds. We refer to this suite of
tools as Mantoo (Management tools). Mantoo includes an extensible web-based
graphical topology designer, which provides different layered network "views"
(e.g. from physical links to service relationships among nodes). The suite can
validate an input topology, automatically deploy it over a Mininet emulator or
a distributed SDN testbed and allows access to emulated nodes by opening
consoles in the web GUI. Mantoo provides also tools to evaluate the performance
of the deployed nodes.Comment: Accepted for publication in IEEE Transaction of Network and Service
Management - December 2015 http://dx.doi.org/10.1109/TNSM.2015.250762
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