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[en] The last few years the electronic highway has become quite a topic. The central issue is where and when do we have to join in? The electronic highway offers both opportunities and threats to the energy sector. The energy distribution companies' attitude should be powered by a long-term vision on the future use of the electronic highway. And in the short run the first moves can be made without the need for very high investments. 1 fig., 2 ills
[en] The wireless local area networks represent an alternative to custom sensors and dedicated surveillance systems for target indoor detection. The availability of the channel state information has opened the exploitation of the spatial and frequency diversity given by the orthogonal frequency division multiplexing. Such a fine-grained information can be used to solve the detection problem as an inverse scattering problem. The goal of the detection is to reconstruct the properties of the investigation domain, namely to estimate if the domain is empty or occupied by targets, starting from the measurement of the electromagnetic perturbation of the wireless channel. An innovative inversion strategy exploiting both the frequency and the spatial diversity of the channel state information is proposed. The target-dependent features are identified combining the Kruskal-Wallis test and the principal component analysis. The experimental validation points out the detection performance of the proposed method when applied to an existing wireless link of a WiFi architecture deployed in a real indoor scenario. False detection rates lower than 2 [%] have been obtained. (paper)
[en] This paper presents the research developed at Universidad Nacional de Colombia about the e-Manufacturing platform that is being developed and implemented at LabFabEx (acronym in Spanish as "Laboratorio Fabrica Experimental"). This platform besides has an approach to virtual-remote labs that have been tested by several students and engineers of different industrial fields. At this paper it is shown the physical and communication experimental platform, the general scope and characteristics of this e-Manufacturing platform and the virtual lab approach. This research project is funded by COLCIENCIAS (Administrative Department of science, technology and innovation in Colombia) and the enterprise IMOCOM S.A
[en] Programmable logic controllers (PLCs) are widely used to realize slow control and interlock control of the accelerator control system. Along with the development of the industrial control technology, data exchanging between PLC and upper computer is usually based on the ethernet communication. An embedded IOC prototype was built for communication between PLC and EPICS using the YOKOGAWA FA-M3 PLC and a new CPU module F3RP61. The embedded EPICS IOC Core was run in F3RP61, which makes the FA-M3 PLC with F3RP61 becomes a new type of embedded IOC. Therefore, the data of the FA-M3 PLC can go straight into the EPICS. This framework makes the structure of the control system simple. As a result, the development costs will be reduced. (authors)
[en] A review of the state of the Internet in terms of traffic and services trends covering both the Research and Education and the Commercial Internet will first be given. The problematic behind the IPv4 to IPv6 migration will be explained shortly, a short review of the ongoing efforts to re-design the Internet in a clean-slate approach will then be made.
[en] We study the attack vulnerability of network with duplication-divergence mechanism. Numerical results have shown that the duplication-divergence network with larger retention probability σ is more robust against target attack relatively. Furthermore, duplication-divergence network is broken down more quickly than its counterpart BA network under target attack. Such result is consistent with the fact of WWW and Internet networks under target attack. So duplication-divergence model is a more realistic one for us to investigate the characteristics of the world wide web in future. We also observe that the exponent γ of degree distribution and average degree are important parameters of networks, reflecting the performance of networks under target attack. Our results are helpful to the research on the security of network.