Protocol assessment issues in low duty cycle sensor networks: The switching energy

Energy assessment of MAC protocols for wireless sensor networks is generally based on the times of transmit, receive and sleep modes. The switching energy between two consecutive states is generally considered negligible with respect to them. Although such an assumption is valid for traditional wireless ad hoc networks, is this assumption valid also for low duty cycle wireless sensor networks? The primary objective of this work is to shed some light on relationships between node switching energy and node duty cycle over the total energy consumption. In order to achieve the target, initially, we revisit the energy spent in each state and transitions of three widespread hardware platforms for wireless sensor networks by direct measurements on the EYES node. Successively, we apply the values obtained to the SMAC protocol by using the OmNet++ simulator

The CLARITY modular ambient health and wellness measurement platform

Emerging healthcare applications can benefit enormously from recent advances in pervasive technology and computing. This paper introduces the CLARITY Modular Ambient Health and Wellness Measurement Platform:, which is a heterogeneous and robust pervasive healthcare solution currently under development at the CLARITY Center for Sensor Web Technologies. This intelligent and context-aware platform comprises the Tyndall Wireless Sensor Network prototyping system, augmented with an agent-based middleware and frontend computing architecture. The key contribution of this work is to highlight how interoperability, expandability, reusability and robustness can be manifested in the modular design of the constituent nodes and the inherently distributed nature of the controlling software architecture.Emerging healthcare applications can benefit enormously from recent advances in pervasive technology and computing. This paper introduces the CLARITY Modular Ambient Health and Wellness Measurement Platform:, which is a heterogeneous and robust pervasive healthcare solution currently under development at the CLARITY Center for Sensor Web Technologies. This intelligent and context-aware platform comprises the Tyndall Wireless Sensor Network prototyping system, augmented with an agent-based middleware and frontend computing architecture. The key contribution of this work is to highlight how interoperability, expandability, reusability and robustness can be manifested in the modular design of the constituent nodes and the inherently distributed nature of the controlling software architecture

A Low-Latency Routing Protocol for Wireless Sensor Networks

Advanced Industrial Conference on Wireless Technologies (ICW 2005), August 14-17, 2005, Montreal, CanadaRecent advances in wireless sensors network (WSN) technology have made possible the manufacturing of tiny low-cost, low-power sensors with wireless multi-hop communication and sensing capabilities. Energy conservation for WSNs is a primary objective that needs to be addressed at all layers of the networking protocol stack. In many applications latency is another crucial factor to be addressed. However this must be done in the context of the energy constraints imposed by the network. In this paper we present an experimental evaluation of two node scheduling regimes within MERLIN (MAC energy efficient, routing and localization integrated), an energy-efficient low-latency integrated protocol for WSNs. In particular we contrast the X and V scheduling family schemes with respect to the following properties: network setup time, network lifetime and message latency. We conduct our experiments within the OmNet++ simulator.A

Managing Mobile-based Participatory Sensing Communities

Participation of mobile phone users in sensorial data collection both from the individual and from the surrounding environment presents a wide range of opportunities for truly pervasive applications. This paper highlights relevant issues related to mobile-phone participatory sensing and describes an architecture framework to flexibly create new communities of data interest, to manage and interact with those communities and to finally provide useful information to the users.

Evaluation of energy-efficiency in lighting systems using sensor networks

Paper presented at Buildsys: First ACM Workshop On Embedded Sensing Systems For Energy-Efficiency In Buildings, 3 Nov, Berkeley, USAIn modern energy aware buildings, lighting control systems are put in place so to maximise the energy-efficiency of the lighting system without effecting the comfort of the occupant. In many cases this involves utilising a set of presence sensors, with actuators, to determine when to turn on/off or dim lighting, when it is deemed necessary. Such systems are installed using standard tuning values statically fixed by the system installer. This can cause inefficiencies and energy wastage as the control system is never optimised to its surrounding environment. In this paper, we investigate a Wireless Sensor Network (WSN) as a viable tool that can help in analysing and evaluating the energy-efficiency of an existing lighting control system in a low-cost and portable solution. We introduce LightWiSe (LIGHTting evaluation through WIreless SEnsors), a wireless tool which aims to evaluate lighting control systems in existing office buildings. LightWiSe determines points in the control system that exhibit energy wastage and to highlight areas that can be optimised to gain a greater efficiency in the system. It will also evaluate the effective energy saving to be obtained by replacing the control system with a more judicious energy saving solution. During a test performed in an office space, with a number of different lighting control systems we could highlight a number of areas to reduce waste and save energy. Our findings show that each system tested can be optimised to achieve greater efficiency. LightWiSe can highlight savings in the region of 50% to 70% that are achievable through optimising the current control system or installing an alternative.Science Foundation IrelandConference detailshttp://buildsys.ucd.ie

Real-time recognition and profiling of appliances through a single electricity sensor

Paper presented at Sensor Mesh and Ad Hoc Communications and Networks (SECON), 2010 7th Annual IEEE Communications Society Conference, Boston, Massachusetts, 21-25 June, 2010Sensing, monitoring and actuating systems are expected to play a key role in reducing buildings overall energy consumption. Leveraging sensor systems to support energy efficiency in buildings poses novel research challenges in monitoring space usage, controlling devices, interfacing with smart energy meters and communicating with the energy grid. In the attempt of reducing electricity consumption in buildings, identifying individual sources of energy consumption is key to generate energy awareness and improve efficiency of available energy resources usage. Previous work studied several non-intrusive load monitoring techniques to classify appliances; however, the literature lacks of an comprehensive system that can be easily installed in existing buildings to empower users profiling, benchmarking and recognizing loads in real-time. This has been a major reason holding back the practice adoption of load monitoring techniques. In this paper we present RECAP: RECognition of electrical Appliances and Profiling in real-time. RECAP uses a single wireless energy monitoring sensor easily clipped to the main electrical unit. The energy monitoring unit transmits energy data wirelessly to a local machine for data processing and storage. The RECAP system consists of three parts: (1) Guiding the user for profiling electrical appliances within premises and generating a database of unique appliance signatures; (2) Using those signatures to train an artificial neural network that is then employed to recognize appliance activities (3) Providing a Load descriptor to allow peer appliance benchmarking. RECAP addresses the need of an integrated and intuitive tool to empower building owners with energy awareness. Enabling real-time appliance recognition is a stepping-stone towards reducing energy consumption and allowing a number of major applications including load-shifting techniques, energy expenditure breakdown per appliance, detection of power hungry and faulty appliances, and recognition of occupant activity. This paper describes the system design and performance evaluation in domestic environment.Science Foundation Irelandti, ab, co - TS 02.02.1

NetBem : business equipment energy monitoring through network auditing

Presented at the 2nd ACM Workshop On Embedded Sensing Systems For Energy-Efficiency In Buildings (BuildSys 2010), at ACM SenSys 2010, Zurich, Switzerland, November 2, 2010Modern office buildings are fully equipped and furnished spaces with arrangements including networked business equipment, such as PC-class machines, copiers, wireless routers and fax machines, and other electrical equipment such as home appliances e.g. coffee machines, and appliances for environmental comfort e.g. electric heaters. The unique characteristics of networked business equipment are well-defined usage pattern, low-power current draw, and connectivity to the local area network (LAN). Business equipment is generally used over working hours adding up to important costs, motivating the need for a system capable of tracking equipment usage and associated energy expenditure, as well as identifying cost saving opportunities. Techniques for monitoring power loads are generally based on power step edge detection, and cannot be applied to business equipment due to the low power consumption of individual devices. This paper presents NetBem, a novel energy monitoring technique ad hoc to office buildings, capturing the contribution of networked business equipment to a power load via side-band detection of the equipment’s operating state through the LAN. The technique is presented, and results from experiments within the School of Computer Science and Informatics at University College Dublin in Ireland are given.Science Foundation IrelandConference detailshttp://buildsys.org/2010

On the RFID wake-up impulse for multi-hop sensor networks

Communication protocols for wireless sensor networks reduce the energy consumption by duty cycling the node activity and adopting a periodic sleeping scheduling. This approach often results in idle listening and therefore energy dissipated for listening to a channel free from packet transmitted. Duty cycling trades-off energy consumption due to idle listening and high end-to-end delay. Proposed solutions mitigate this issue for example through extra low-power radio components (wake-up radio) that listen to the radio and wake-up the node if some channel activity is sensed. These extra components also consume some energy to listen to the channel. In contrast, we propose an on-demand wake-up capability, namely RFIDimpulse, which is achieved through using an off-the-shelf batteryless RFID tag attached to each sensor node that is also provided with RFID reader capability. Because modern RFID techniques can trigger all the neighbouring tags at once or pinpoint a particular tag, RFIDimpluse provides both unicast and multicast capability. RFIDimpulse allows eventdriven communication and eliminates node idle listening.

Autonomous management and control of sensor network-based applications

Paper presented at the 2nd International Workshop on Adaptation in Wireless Sensor Networks (AWSN-09), in conjunction with The 7th IEEE/IFIP International Conference on Embedded and Ubiquitous Computing (EUC 2009), August 29 - 31, 2009, Vancouver, CanadaA central challenge facing sensor network research and development is the difficulty in providing effective autonomous management capability. This is due to a large number of parameters to control, unexpected changes of the network topology and dynamic application requirements. Network management is also a challenging task for the remote user due to the large-scale of the network and scarce visibility of live network happenings. Preferably the network should have autonomous decision-making capabilities as network conditions and application requirements changes. To cope with such uncertainties, firstly we consider Octopus, a powerful software tool that provides live information about the network topology and sensor data. At present, the tool can provide monitoring and require a user to control the network state manually. This paper describes how Octopus is reengineered to accommodate a multi-agent system to provide autonomic managing capabilities. In particular, we detail two distinct architectures, the static and mobile agent architectures, which can be effectively applied to deliver autonomous system management. This paper sets the basis for a full autonomous network management via a multi agent system to work with Octopus.Science Foundation IrelandConference detailshttp://tweb.ing.unipi.it/awsn09

Demo abstract : appliance load monitoring by power load disaggregation

Paper presented at the 2010 7th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON), 21-25 June, 2010, Boston, MassachusettsAppliance load monitoring systems are designed to disaggregate the power load of a building in order to estimate the nature of individual loads, providing a real-time fine-grained recognition of active appliances. Monitoring non-intrusively appliances’ contributions to a given load enables a wide range of applications, ranging from electricity bill decomposition to accurate electricity user profiling. This work demonstrates a real implementation of such appliance load monitoring system. An intuitive graphical user interface is proposed to drive the system setup for profiling appliances’ signatures and for visualising the monitoring output.Science Foundation IrelandConference websitehttp://www.ieee-secon.com/2010/ti, ke, ab - kpw9/12/1