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The use of network infrastructures to replace conventional professional audio systems is a rapidly increasing field which is expected to play an important role within the professional audio industry. Currently, the market is dominated by numerous proprietary protocols which do not allow interoperability and do not promote the evolution of this sector. Recent standardization actions are intending to resolve this issue excluding, however, the use of wireless networks. Existing wireless networking technologies are considered unsuitable for supporting real-time audio networks, not because of lack of bandwidth but due to their inefficient congestion control mechanisms in broadcasting. In this paper, we propose an amendment of the IEEE 802.11 MAC that improves the performance of the standard for real-time audio data delivery. The proposed amendment is offering a solution for the balancing of data flow density in wireless ad-hoc networks for a multi-broadcasting environment. It is based on two innovative ideas. First, it provides a protection mechanism for broadcasting and second, it replaces the classic congestion control mechanism, based in random backoff, with an alternative traffic adaptive algorithm, designed to minimize collisions. The proposed MAC is able to operate as an alternative mode allowing regular Wi-Fi networks to coexist and interoperate efficiently with audio networks, with the last ones being able to be deployed over existing wireless network infrastructures.

Gene expression programming (GEP) is a data driven evolutionary technique that well suits for correlation mining. Parallel GEPs are proposed to speed up the evolution process using a cluster of computers or a computer with multiple CPU cores. However, the generation structure of chromosomes and the size of input data are two issues that tend to be neglected when speeding up GEP in evolution. To fill the research gap, this paper proposes three guiding principles to elaborate the computation nature of GEP in evolution based on an analysis of GEP schema theory. As a result, a novel data engineered GEP is developed which follows closely the generation structure of chromosomes in parallelization and considers the input data size in segmentation. Experimental results on two data sets with complementary features show that the data engineered GEP speeds up the evolution process significantly without loss of accuracy in data correlation mining. Based on the experimental tests, a computation model of the data engineered GEP is further developed to demonstrate its high scalability in dealing with potential big data using a large number of CPU cores. National Fundamental Research Program (973) of China; 10.13039/501100003399-Science and Technology Commission of Shanghai Municipality; European Union’s Horizon 2020 research and innovation programme

The growing need for multimedia applications within wireless Local Area Networks (LAN) demands reliable and efficient broadcasting and multicasting transmission of throughput sensitive data, like audio and video. IEEE 802.11 standard which is the primary technology in wireless LANs was not initially designed to handle heavy broadcasting traffic. However, this raises a series of reliability problems mainly related to the lack of an effective feedback mechanism for multicasting and broadcasting transmission. This inherited drawback does not allow the standard to take full advantage of the bandwidth offered by its latest amendments. The main aim of this work is to offer an alternative congestion control mechanism especially for broadcasting. For this, the expanding use of the CTS-to-Self protection mechanism is proposed. The Medium Access Control (MAC) algorithm is appropriately modified and tested under various data traffic conditions. The simulation shows that the use of this amended MAC method in conjunction with the suitable data packet size can significantly improve throughput, in multimedia type data broadcasting over wireless ad-hoc networks.

This paper proposes a new information model of smart consumers where the appliances are not regarded independently such as in traditional scheduling algorithms or home energy management systems, but through a set of common attributes that make up the generic appliance model. Each appliance is generalized by its set of particular attributes. The novel vision is introduced and the attributes of the generic appliance model are explained. The functionality of the system is described with emphasis on the interactions between system components. Under the novel vision, home energy management systems could be developed into widely used practical implementations that would allow better management and user interaction within the home environment.

A prototype platform was designed, implemented and tested to act as the foundation of a novel intelligent home energy management system which can manage the overall consumption of a house while taking into account user preferences and dynamic tariffs. In order to reduce the implementation cost and to increase the platform stability, the system was designed to employ independent stand-alone devices based on microcontrollers.

Multimedia applications over wireless networks have dramatically increased over the past years. Numerous new devices and applications that distribute audio and video over wireless networks are introduced every day and all of them demands a reliable and efficient wireless standard. Either operating as independent ad-hoc networks or as terminal parts of wired networks or the internet, wireless networks are frequently facing the need to broadcast multimedia data from multiple sources to multiple users. IEEE 802.11 standard (Wi-Fi) is the primary technology in wireless networking today. However, it has some inherited problems when it comes to broadcasting caused mainly by the lack of an acknowledgment mechanism. These problems do not allow the standard to take full advantage of the bandwidth offered by its latest amendments. In this paper two independent modifications of the medium access control (MAC) mechanism of the standard, are proposed along with the expanded use of the CTS-to-Self protection mechanism. The main objective of this study is to explore the ability of the modified MAC mechanisms to improve broadcasting performance while are operating in conjunction with a regular wireless network, and also to define the cases were the use of CTS-to-Self-protection mechanism can improve the overall performance of the network. The results show that the overall performance can be improved using these alternative MAC methods. Also, the cases where the CTS-to-Self technique can additionally contribute to the network performance are defined and analyzed.

Internet Protocol (IP) suite and Ethernet physical layer are the current trend in home and industrial systems communication protocols. Unfortunately, in the field of power line automation protocols that are in wide use in home automation applications, the lack of IP convergence leads to difficulties, because of the variety and high costs of systems and solutions that need to be integrated. This paper presents a simple and reliable convergence mechanism of open power line Home Automation Protocols to IP (HAPoIP), which is implemented and tested for X10 protocol, on a low cost platform. The novelty and the achievement of the proposed system is the integration of heterogeneous automation networks through IP. In addition, the system was built in terms of software and hardware based on a new protocol.