770 resultados para , Wireless Sensor Network


Relevância:

30.00% 30.00%

Publicador:

Resumo:

A recent trend in networked control systems (NCSs) is the use of wireless networks enabling interoperability between existing wired and wireless systems. One of the major challenges in these wireless NCSs (WNCSs) is to overcome the impact of the message loss that degrades the performance and stability of these systems. Moreover, this impact is greater when dealing with burst or successive message losses. This paper discusses and presents the experimental results of a compensation strategy to deal with this burst message loss problem in which a NCS mathematical model runs in parallel with the physical process, providing sensor virtual data in case of packet losses. Running in real-time inside the controller, the mathematical model is updated online with real control signals sent to the actuator, which provides better reliability for the estimated sensor feedback (virtual data) transmitted to the controller each time a message loss occurs. In order to verify the advantages of applying this model-based compensation strategy for burst message losses in WNCSs, the control performance of a motor control system using CAN and ZigBee networks is analyzed. Experimental results led to the conclusion that the developed compensation strategy provided robustness and could maintain the control performance of the WNCS against different message loss scenarios.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Several countries have invested in technologies for Smart Grids. Among such protocols designed cover this area, highlights the DNP3 (Distributed Network Protocol version 3). Although the DNP3 be developed for operation over the serial interface, there is a trend in the literature to the use of other interfaces. The Zigbee wireless interface has become more popular in the industrial applications. In order to study the challenges of integrating of these two protocols, this article is presented the analysis of DNP3 protocol stack through state machines The encapsulation of DNP3 messages in P2P (point-to-point) ZigBee Network, may assist in the discovery and solution of failures of availability and security of this integration. The ultimate goal is to merge the features of DNP3 and Zigbee stacks, and display a solution that provides the benefits of wireless environment, without impairment of security required for Smart Grid applications.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Internet access by wireless networks has grown considerably in recent years. However, these networks are vulnerable to security problems, especially those related to denial of service attacks. Intrusion Detection Systems(IDS)are widely used to improve network security, but comparison among the several existing approaches is not a trivial task. This paper proposes building a datasetfor evaluating IDS in wireless environments. The data were captured in a real, operating network. We conducted tests using traditional IDS and achieved great results, which showed the effectiveness of our proposed approach.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Faced with an imminent restructuring of the electric power system, over the past few years many countries have invested in a new paradigm known as Smart Grid. This paradigm targets optimization and automation of electric power network, using advanced information and communication technologies. Among the main communication protocols for Smart Grids we have the DNP3 protocol, which provides secure data transmission with moderate rates. The IEEE 802.15.4 is another communication protocol also widely used in Smart Grid, especially in the so-called Home Area Network (HAN). Thus, many applications of Smart Grid depends on the interaction of these two protocols. This paper proposes modeling, in the traditional network simulator NS-2, the integration of DNP3 protocol and the IEEE 802.15.4 wireless standard for low cost simulations of Smart Grid applications.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The objective of this project is to collaborate with the society, working on a subject that is directly linked to issues of sustainability and environmental preservation. For this, a survey is being developed in order to make possible the creation of an intelligent mechanism, with the use of wireless solutions for the control of energy consumption in order to meet the needs of quality of life and reduce the average consumption of electrical energy. An intelligent lighting system can be explained simply, as an interconnected network of lamps in order to meet needs such as light intensity, the location of it, the moment will turn on or turn off the lights, among other possibilities. This network of lamps is controlled by algorithms implemented using microcontrollers, which may or may not have changed its characteristics. This can be automatic (pre-programmed by the administrator) or manual (controlled via a remote control, phones, etc.), and will depend upon the manager himself and also the characteristics imposed on the project. However, it is important to note that after the search is complete, decisions will be consistent with the Brazilian reality, ie, this system can only be feasible if it has all the characteristics described above, but with an affordable price so that people can acquire it