SENSORNETS 2014 Abstracts


Area 1 - Sensor Networks Software and Architectures

Full Papers
Paper Nr: 18
Title:

SCLD-ATP: Symmetric Coherent Link Degree, Adaptive Transmission Power Control for Wireless Sensor Networks

Authors:

Konstantinos Chantzis, Dimitrios Amaxilatis, Ioannis Chatzigiannakis and Jose Rolim

Abstract: Wireless Sensor Networks (WSNs) are by nature dynamic and communication between sensors nodes is ad hoc. Numerous protocols and applications proposed operate on the assumption that communication channels are stable. Topology Control Protocols are crucial in the operation of WSNs as they adjust transmission power in order to maintain link quality, minimize interference and provide spatial topological control. Analysis of such protocols is performed using theoretical models that are based on unrealistic assumptions like ideal wireless channels and perfect energy consumption and distance estimations. With these assumptions taken for granted, theoretical models claim various performance milestones that cannot be achieved in realistic conditions. We here present a topology control protocol that is deployable in real WSNs and distance ourselves from spatial, temporal, environmental assumptions regarding the performance of communications on the wireless medium. Our protocol focuses on fault tolerance and symmetric link coherence using an adaptive transmission power scheme. From various testbed experiments we showcase the performance of SCLD-ATP in terms of load balancing, reliability, multi-hop capabilities and power consumption.

Paper Nr: 29
Title:

Enabling Quality Control of Sensor Web Observations

Authors:

Anusuriya Devaraju, Ralf Kunkel, Juergen Sorg, Heye Bogena and Harry Vereecken

Abstract: The rapid development of sensing technologies had led to the creation of large volumes of environmental observation data. Data quality control information informs users how it was gathered, processed, examined. Sensor Web is a web-centric framework that involves observations from various providers. It is essential to capture quality control information within the framework to ensure that observation data are of known and documented quality. In this paper, we present a quality control framework covering different environmental observation data, and show how it is implemented in the TERENO data infrastructure. The infrastructure is modeled after the OGC’s Sensor Web Enablement (SWE) standards.

Paper Nr: 40
Title:

A Constraint Programming Approach for Managing End-to-end Requirements in Sensor Network Macroprogramming

Authors:

Farshid Hassani Bijarbooneh, Animesh Pathak, Justin Pearson, Valerie Issarny and Bengt Jonsson

Abstract: Though several high-level application development (macroprogramming) approaches have been proposed in literature for wireless sensor networks (WSN), there is a need to enable support for expressing and supporting end-to-end non-functional constraints such as latency in WSN macroprograms. We augment an existing macroprogramming language and its compilation process to enable the specification of end-to-end requirements, and propose task mapping algorithms to satisfy those requirements through a constraint programming approach. Through evaluations on realistic application task graphs, we show that our constraint programming model can effectively capture the end-to-end requirements and efficiently solves the combinatorial problem introduced.

Paper Nr: 52
Title:

Life Time Sensitive Weighted Clustering on Wireless Sensor Networks

Authors:

Elnaz Alizadeh Jarchlo and Cüneyt F. Bazlamaçcı

Abstract: The present paper considers weighted clustering algorithms for mobile ad hoc networks (MANET) and wireless sensor networks (WSN). First, we summarize the similarities and differences between the two types of networks as then examine the existing weighted clustering algorithms proposed so far. We specifically examine the objective functions and performances of the algorithm in terms of various parameters. In addition, we proposed a new algorithm called as the Life Time Sensitive Weighted Clustering Algorithm (LTS-WCA), which aims to adapt the already existing weighted clustering algorithm (WCA) proposed for MANET to WSN and modify and enhance it. WCA was proposed in the literature for forming cluster-heads in mobile ad hoc networks but we have demonstrated that it can also be effective when used in a wireless sensor network domain.

Paper Nr: 72
Title:

Sensing Gestures for Business Intelligence

Authors:

David Bell, Nikhil Makwana and Chidozie Mgbemena

Abstract: The combination of sensor data with analytic techniques is growing in popularity for both practitioners and researchers as an Internet of Things (IoT) offers new opportunities and insights. Organisations are trying to use sensor technologies to derive intelligence and gain a competitive edge in their industries. Obtaining data from sensors might not pose too much of a problem, however subsequent utilisation in meeting an organisation’s decision making can be more problematic. Understanding how sensor data analytics can be undertaken is the first step to deriving business intelligence from front line retail environments. This paper explores the use of the Microsoft Kinect sensor to provide intelligence by identifying and sensing gestures to better understand customer behaviour in the retail space.

Short Papers
Paper Nr: 14
Title:

Handling Time and Reactivity for Synchronization and Clock Drift Calculation in Wireless Sensor/Actuator Networks

Authors:

Marcel Baunach

Abstract: The precise temporal attribution of environmental events and measurements as well as the precise scheduling and execution of corresponding reactions is of utmost importance for networked sensor/actuator systems. Apart, achieving a well synchronized cooperation and interaction of these wirelessly communicating distributed systems is yet another challenge. This paper summarizes various related problems which mainly result from the discretization of time in digital systems. As an improvement, we'll present a novel technique for the automatic creation of highly precise event timestamps, as well as for the scheduling of related (re-)actions and processes. Integrated into an operating system kernel at the lowest possible software level, we achieve a symmetric error interval around an average temporal error close to 0 for both the timestamps and the scheduled reaction times. Based on this symmetry, we'll also introduce a dynamic self-calibration technique to achieve the temporally exact execution of the corresponding actions. An application example will show that our approach allows to determine the clock drift between two (or more) independently running embedded systems without exchanging any explicit information, except for the mutual triggering of periodic interrupts.

Paper Nr: 46
Title:

Resilient Supervision System over WSAN - A Distributed Multi-Agent Architecture

Authors:

Fábio Januário, Amâncio Santos, Catarina Lucena, Luis Palma, Alberto Cardoso and Paulo Gil

Abstract: Wireless Sensor and Actuator Networks enable flexibility, low operational and maintenance costs, as well as scalability in a variety of scenarios. However, in the context of remote control and monitoring applications the use of Wireless Sensor and Actuator Networks can impact the system’s performance due to several factors, such as outliers in sampled raw data, communication breakdown or owing to security issues. In order to improve the overall system’s resilience, this paper proposes a distributed hierarchical multi-agent architecture where each agent is responsible for a specific task. Experimental results collected from a laboratory test-bed show the relevance of incorporating the proposed methodology in the context of monitoring and networked control systems over Wireless Sensor and Actuator Networks.

Paper Nr: 60
Title:

M3: Machine-to-Machine Management Framework

Authors:

Heikki Mahkonen, Tony Jokikyyny, Jaime Jimenéz and Sławomir Kukliński

Abstract: The number of deployed sensor devices with Internet connection is expected to exceed 50 billion units. Many of these devices spend most of their time in sleep mode to conserve energy. This sets new kinds of requirements for network management, and creates the need of redesigning conventional network management. Hence, most of the manual deployment, configuration and operation tasks need to be automated in a scalable fashion, using protocols that can deal with the uncertainty caused by the intermittent nature of the devices. For scalability reasons, the network management logic needs to be distributable in the network management architecture. In this document we describe our management framework for M2M networks. It is also shown, how the framework has been implemented as a prototype testbed. We have used the testbed to study centralized and de-centralized M2M network management logic for different management scenarios.

Paper Nr: 61
Title:

Using Embedded Sensors in Smartphones to Monitor and Detect Early Symptoms of Exercise-induced Asthma

Authors:

Chinazunwa Uwaoma and Gunjan Mansingh

Abstract: This paper describes work in progress on integrated design architecture for monitoring and detecting early symptoms of asthma attack using smartphone as sensors’ platform for data capturing, processing, presentation and feedback. We present an application scenario of exercise-induced asthma where a patient wears a smartphone equipped with built-in sensors which are capable of providing clinical data and context on detection of any anomaly in the monitored vital signs. Our design architecture extends the functionality of “Nine-degree of Freedom” (9-DoF) sensor fusion model and context recognition using expert system frameworks. The design centers on the idea of creating a simple and portable asthma monitoring system that is able to detect asthma vital signs, perform signal analysis and context generation; and also send information to other mobile devices worn by caregivers and physicians. This approach removes the need to have external monitoring sensors patched on the user’s body, thereby enhancing the usability and reliability of the system in providing timely information on the state of a patient’s health.

Posters
Paper Nr: 19
Title:

An Architecture for Seamless Configuration, Deployment, and Management of Wireless Sensor-actuator Networks

Authors:

Edgard Neto, Rui Mendes and Luís Lopes

Abstract: The goal of this work is to provide (non-specialist) users with the means to seamlessly setup and monitor a Wireless Sensor-Actuator Network (WSN) without writing any code or performing subtle hardware configurations. Towards this goal, we present an architecture that allows the seamless configuration, deployment and management of applications over WSN. We explore the fact that most deployments have a common modus operandi: (a) simple data readers running on the nodes periodically gather and send data to sinks, and; (b) sinks process incoming data and, accordingly, issue actuation commands to the nodes. We argue that, given the knowledge of a platform’s capabilities, its sensors and actuators and their respective programming interfaces, it is possible to fully automate the process of configuring, building, and deploying an application over a WSN. Similarly, monitoring and managing the deployment can be vastly simplified by using a middleware that supports user defined tasks that process data from the nodes, divide the WSN into regions, defined by simple boolean predicates over data, and eventually issue actuation commands on regions.

Paper Nr: 22
Title:

Performance Evaluation of Routing Schemes in Wireless Sensor Networks for Train Monitoring

Authors:

Oussama Drissi, Adel Omar Dahmane and Tayeb Medjeldi

Abstract: Wireless sensor technologies offer new opportunities in different applications thanks to the great technological progress in the development of smart sensors, powerful processors and wireless communication protocols. In this paper, performance evaluation of two network topologies based on routing strategies for train monitoring has been conducted in a realistic mesh sensing system. Results conducted in NS2 using Mannasim extension show that Multi-tier multi-hop topology outperforms the classic multi-hop topology in terms of end-to-end delay, throughput and residual energy level.

Paper Nr: 25
Title:

A Proposal for an Internet of Things-based Monitoring System Composed by Low Capability, Open Source and Open Hardware Devices

Authors:

Jesus Rodriguez-Molina, José-Fernán Martínez, Gregorio Rubio and Vicente Hernández

Abstract: The Internet of Things makes use of a huge disparity of technologies at very different levels that help one to the other to accomplish goals that were previously regarded as unthinkable in terms of ubiquity or scalability. If the Internet of Things is expected to interconnect every day devices or appliances and enable communications between them, a broad range of new services, applications and products can be foreseen. For example, monitoring is a process where sensors have widespread use for measuring environmental parameters (temperature, light, chemical agents, etc.) but obtaining readings at the exact physical point they want to be obtained from, or about the exact wanted parameter can be a clumsy, time-consuming task that is not easily adaptable to new requirements. In order to tackle this challenge, a proposal on a system used to monitor any conceivable environment, which additionally is able to monitor the status of its own components and heal some of the most usual issues of a Wireless Sensor Network, is presented here in detail, covering all the layers that give it shape in terms of devices, communications or services.

Paper Nr: 32
Title:

An Adaptable Framework for Interoperating Between Wireless Sensor Networks and External Applications

Authors:

Thanh-Dien Tran, David Nunes, Carlos Herrera and Jorge Sá Silva

Abstract: Wireless Sensor Networks (WSNs) are considered the bridge to connect physical and digital worlds and thus an important element of the Future Internet. Consequently, integrating WSNs with external applications is an undeniable requirement. A gateway-based solution in which the sensed data and functions of WSNs are exposed as web services is a common approach. The problem of current integration solutions for WSNs is their adaptability, i.e., the ability to reuse gateways and proxies in a multitude of sensor networks with different types of applications and data frames. In this paper, we present our proposal for this problem by proposing a framework that uses a language for describing the traffic in sensor networks named Sensor Traffic Description Language (STDL). In order to reuse the framework on a new sensor network, it is only necessary to describe the network's frame structures using STDL.

Paper Nr: 33
Title:

LA6 - Local Aggregation in the Internet of Things

Authors:

Bruno Graça Coelho and Rui M. Rocha

Abstract: The Internet of Things concept is leaving its toddler age where essentially it is a research issue and becoming a key player in many current applications where Smart Cities are perhaps its greatest exponent. In such real-world scenarios, efficient large scale machine-to-machine communication is of utmost importance. However, the current 6LoWPAN standard, proposed by the IETF, has some efficiency problems which can make its application to the Internet of Things very difficult to scale up. This work transforms the existent 6LoWPAN implementation enabling a data-centric solution that will overcome the current viability issues of 6LoWPAN in these networks through the integration of an in-network data processing aggregation mechanism. The proposed data aggregation mechanism increases dramatically the sustainability and network lifetime of 6LoWPAN based sensor networks, contributing directly to the Internet of Things revolution.

Paper Nr: 39
Title:

Sensing Real-time Observatories in Marine Sites - A Proof-of-Concept

Authors:

Alessandro Oggioni, Mauro Bastianini, Paola Carrara, Tiziano Minuzzo and Fabio Pavesi

Abstract: Managing real time data collected by a network of heterogeneous sensors from marine sites needs to face challenges such heterogeneity, quality check, harmonization, description of sensors, etc. This is the purpose of the proof-of-concept described in this paper; it tests the suitability of OGC Sensor Web Enablement services, exploiting in particular the Sensor Observation Service (SOS) and the associated SensorML and O&M standards. Two Italian marine observatories have been included in the proof, both belonging to CNR ISMAR; they are the oceanographic Platform “Acqua Alta” and a weather station in Venice (Italy). They measure multiple real time parameters and distribute them by OGC SOS. The multilayer architecture and the service approach adopted enable decoupling of components; in particular, the proof shows that each Institution hosting a sensor station is allowed to store observations and deliver them to multiple independent clients, in a standard, interoperable way, well recognized and accepted at European and global scale. The proof has been implemented and tested in three scenarios to retrieve and display descriptions of stations, sensors and measurements available; to retrieve and display observations of one parameter selected from multiple sensors; to retrieve observations of all parameters collected from sensors of a specific station.

Paper Nr: 51
Title:

Homogeneous Wireless Sensor Network Programming using MuFFIN

Authors:

Rui Pires, Francisco Martins and Dulce Domingos

Abstract: Web services have been used as an homogeneous interface between client applications and sensor networks. The MuFFIN middleware makes possible for a client application to remotely (re)program sensor networks. However, this (re)programming is dependent on the characteristics of the hardware or of the programming languages provided by manufacturers. To generalize this feature, we propose a middleware extension to include the execution of code on behalf of sensor devices in case they are not (re)programmable. As a proof of concept, we use the MuFFIN middleware and the Callas sensor programming language together with its virtual machine. Additionally, we extend the MuFFIN with a component that supports the communication between two wireless sensor networks. This way, messages can flow from one network to another one without the intervention of the client application, reducing the number of messages exchanged between sensor networks and client applications.

Paper Nr: 55
Title:

Priority Enabled Distance-energy based Routing Algorithm for UWSN

Authors:

C. P. Gupta, Mayank Bisht and Arun Kumar

Abstract: Underwater Sensor Networks (UWSNs) are being deployed for range of applications like collection of oceanic data for research, military surveillance, disaster prevention, underwater exploration etc. Characteristics such as use of acoustic signal for communication, 3D deployment, and higher losses make routing in UWSNs different from terrestrial sensor networks. In this paper, we present a location aware routing algorithm based on routing factor (Rf); a function of distance and energy. In our proposed algorithm, forwarding node is selected by sender amongst its neighbors depending on their distance from destination node and residual energy. To consider energy with distance, Energy scale value (Es) is used as a scaling range. Priority packets are also used for quick delivery of packets. Simulation results show improved performance of our routing algorithm in terms of network lifetime and end to end delay.

Area 2 - Wireless Information Networks

Full Papers
Paper Nr: 30
Title:

Performance Analysis of Random Relaying of Partitioned MDS Codeword Block Applied to Persistent Relay CSMA over Random Error Channels

Authors:

Katsumi Sakakibara and Jumpei Taketsugu

Abstract: We propose incorporation of Random relaying of Partitioned Maximum Distance Separable codeword blocks (RP-MDS), which has been proposed for multi-hop cooperative relay networks, to Persistent Relay Carrier Sense Multiple Access (PRCSMA) over noisy channels. The proposed protocol elaborately employs the powerful error-correcting capability of MDS codes into cooperative communication systems and introduces the incremental redundancy concept to PRCSMA. A destination node can reinforce an error-correcting capability when it receives a new frame. The performance of the proposed protocol is analyzed with a Markov model in terms of the average duration of a cooperation phase and the energy efficiency. Numerical results indicate that the proposed protocol can significantly improve the performance, compared to the original PRCSMA.

Paper Nr: 71
Title:

Geographic Routing with Partial Position Information

Authors:

Tony Ducrocq, Michaël Hauspie and Nathalie Mitton

Abstract: Geographic routing protocols show good properties for Wireless Sensor Networks (WSN). They are stateless, local and scalable. However they require that each node of the network is aware of its own position. While it may be possible to equip each node with GPS receiver, even if it is costly, there are some issues and receiving a usable GPS signal may be difficult in some situations. For these reasons, we propose a geographic routing algorithm, called HGA, able to take advantages of position informations of nodes when available but also able to continue the routing in a more traditional way if position information is not available. We show with simulations that our algorithm offers an alternative solution to classical routing algorithm (non-geographic) and offers better performances for network with a density above 25 and more than 5% of nodes are aware of their position.

Short Papers
Paper Nr: 20
Title:

Peer Synchronization Method for Wireless Sensor Networks using Heterogeneous Bluetooth Sensor Nodes

Authors:

Steffen Dalgard, Franck Fleurey and Anders E. Liverud

Abstract: Synchronization of time is essential for correlation of sensor data. For body area network the sensors are distributed over multiple sensor nodes located on different parts of the body. When collecting sensor data using wireless sensor networks, the delay variation can be up to 1000 milliseconds. Physiological sensors, like ECG, accelerometer and gyroscopes, require a timing accuracy in the millisecond range. This paper describes a generic method to provide synchronized timestamps. The method is tested in a Wireless sensor network using Bluetooth and Bluetooth Smart sensor nodes. Results show that the method is usable for correlating sensor data with 50ms sample rate.

Paper Nr: 35
Title:

A Distributed Greedy Algorithm for Constructing Connected Dominating Sets in Wireless Sensor Networks

Authors:

Akshaye Dhawan, Michelle Tanco and Nicholas Scoville

Abstract: A Connected Dominating Set (CDS) of the graph representing a Wireless Sensor Network can be used as a virtual backbone for routing in the network. Since sensor nodes are constrained by limited on-board batteries, it is desirable to have a small CDS for the network. However, constructing a minimum size CDS has been shown to be a NP-hard problem. In this paper we present a distributed greedy algorithm for constructing a CDS that we call Greedy Connect. Our algorithm operates in two phases, first constructing a dominating set and then connecting the nodes in this set. We evaluate our algorithm using simulations and compare it to the two-hop K2 algorithm in the literature. Depending on the network topology, our algorithm generally constructs a CDS that is up to 30% smaller in size than K2.

Paper Nr: 37
Title:

Combinatorial Approach for Geographic Routing with Delivery Guarantees

Authors:

Kasun Samarasinghe and Pierre Leone

Abstract: In this paper we present a novel combinatorial approach for geographic routing with delivery guarantees. Proposed algorithm can be seen as a variant of GFG (Greedy Face Greedy of Bose et.al) algorithm, but based on the defined combinatorial properties of the graph. We utilize a distributed planarization algorithm of a geometric graph, which is based on the Schnyder’s characterization of planar graphs. The new approach is combinatorial in the sense that the nodes are ordered with respect to three distinct order relations satisfying the suitable properties. The coordinate system motivated the development of this routing algorithm is VRAC (Virtual Raw Anchor Coordinates), which localizes nodes based on the raw distances from three fixed anchors. Since the positions of the anchors need not to be known, the nodes localized by the VRAC coordinate system does not correspond to the exact geographic location of nodes, yet leaving sufficient information to define necessary combinatorial constructs.

Posters
Paper Nr: 36
Title:

A Routing Algorithm based on Semi-supervised Learning for Cognitive Radio Sensor Networks

Authors:

Zilong Jin, Donghai Guan, Jinsung Cho and Ben Lee

Abstract: In Cognitive Radio Sensor Networks (CRSNs), the cognitive radio technology enables sensor nodes to occupy licensed bands in a opportunistic manner and provides advantages in terms of spectrum utilization and system throughput. This paper proposes a routing scheme based on semi-supervised learning, which jointly considers energy efficiency, context-awareness, and optimal path configuration to enhance communication efficiency. A context-aware module is developed to collect and learn context information in an energy-efficient way and a new semi-supervised learning algorithm is proposed to estimate dynamic changes in network environment. A novel routing metric is used to select the most reliable and stable path. Our simulation study shows that the proposed routing algorithm enhances the reliability and stability for CRSNs, and at the same time, significantly improves the packet delivery ratio.

Paper Nr: 38
Title:

Design of an Unstructured and Free Geo-Coordinates Information Brokerage System for Sensor Networks using Directional Random Walks

Authors:

Cristina Muñoz and Pierre Leone

Abstract: The main problem studied in this paper is how to design an efficient method for information brokerage in sensor networks that do not use an overlay layer to organize the network and when geo-coordinates are not provided. We present a method for the solution of this problem using Directional Random Walks (DRWs) which main purpose is to construct a straight path of relaying nodes in the network. When two DRWs intersect the information brokerage system is able to proceed with the data exchange. The implementation of DRWs can be done using one or two branches. Our results reflect that the use of the second neighborhood to forward the DRW does not improve its depth. We also prove that the use of two branches for the construction of the DRW improves latency and that higher densities of nodes in the network lead to the construction of shorter paths. We have used permutations on the top of a well-connected network to test the information brokerage system. The results show that our method is good at balancing the load without using a large amount of nodes. Indeed, we show that the behaviour of DRWs is quite similar to Rumor Routing with an infinite memory.

Paper Nr: 54
Title:

Improving NS-2 Network Simulator to Evaluate IEEE 802.15.4 Wireless Networks Under Error Conditions

Authors:

André Guerreiro, Jeferson L. R. Souza and José Rufino

Abstract: The behaviour of wireless networks in the presence of error conditions is still being studied by the research community. Improvements on the evaluation methods and tools are crucial to acquire a better knowledge, and understanding of the network operation under such conditions. This paper presents enhancements on the network simulator NS-2 to support the evaluation of the IEEE 802.15.4 standard, used as a case study. We are specially interested to evaluate the temporal behaviour of the network operation under errors conditions, considering the applicability of the IEEE 802.15.4 standard in safety-critical environments such as industrial and vehicular.

Paper Nr: 58
Title:

A User Configurable Metric for Clustering in Wireless Sensor Networks

Authors:

Lina Xu, David Lillis, G. M. P. O’Hare and Rem Collier

Abstract: Wireless Sensor Networks (WSNs) are comprised of thousands of nodes that are embedded with limited energy resources. Clustering is a well-known technique that can be used to extend the lifetime of such a network. However, user adaption is one criterion that is not taken into account by current clustering algorithms. Here, the term “user” refers to application developer who will adjust their preferences based on the application specific requirements of the service they provide to application users. In this paper, we introduce a novel metric named Communication Distance (ComD), which can be used in clustering algorithms to measure the relative distance between sensors in WSNs. It is tailored by user configuration and its value is computed from real time data. These features allow clustering algorithms based on ComD to adapt to user preferences and dynamic environments. Through experimental and theoretical studies, we seek to deduce a series of formulas to calculate ComD from Time of Flight (ToF), Radio Signal Strength Indicator (RSSI), node density and hop count according to some user profile.

Paper Nr: 64
Title:

Dynamic Transmission Range based on Packet Reception Ratio and Density in VANETs

Authors:

Muhammad Imran Khan

Abstract: Wireless ad hoc networks provide the local structure for data dissemination to pass the information among the neighbors in a network. In congested vehicular ad hoc networks, there is high probability of the packet collisions that result in loss of information. Fixed transmission range in vehicular networks limits the access of channel if there are high number of neighbor nodes to send and receive the broadcast packets. Loss of event driven safety messages due to collisions and interference and throughput gets minimized in high density of vehicular nodes. This paper presents dynamic change of transmission range in Vehicle-to-Vehicle (V2V) communications that aims at increasing the efficiency of the network by minimizing the loss of packets. The proposed solution to control the transmission range is based on increasing the range or decreasing it depending on the average packet reception ratio and the traffic density. The proposed algorithm provides how transmission range is being changed during the course of a vehicular node on the highway. By this technique Vehicular Ad hoc Networks (VANETs) benefit to reduce loss of packets and to increase the throughput.

Area 3 - Hardware

Full Papers
Paper Nr: 7
Title:

Sensors and Features Selection for Robust Gas Concentration Evaluation

Authors:

D. Ahmadou, E. Losson, M. Siadat and M. Lumbreras

Abstract: This paper seeks to highlight the importance of the knowledge of metal oxide gas sensor behaviour before conceiving an electronic nose for a dedicated application. Therefore, a depth study of sensor response properties is needed for the selection of the more appropriate sensors via optimized measurement conditions and extracted features. Especially for continuous gas evaluation, the most important aspects to consider are the measurement time and the drift of the gas sensors. In this work, for fast recognition of pine oil vapour dilutions, the performance of two features are shown: the maximum of the derivative curve (Peak), an unusual feature which needs a very short gas exposure time, and the sensor amplitude voltage (Vs-V0) obtained at the end of the gas exposition phase. The performance of the new feature Peak, validated by Principal Component Analysis results, leads us to work with the shortest gas exposition and sensor regeneration times, and allows us to choose the best sensors according to our application.

Area 4 - Data Manipulation

Full Papers
Paper Nr: 43
Title:

A Study of Channel Classification Agreement in Urban Wireless Sensor Network Environments

Authors:

Aikaterini Vlachaki, Ioanis Nikolaidis and Janelle Harms

Abstract: We consider a wireless sensor network in an urban environment and attempt to characterize the interference found in the communication channel by means of empirically collected Received Signal Strength Indicator (RSSI) values over Industrial, Scientific and Medical (ISM) and non-ISM bands. We assume a node-based interference classification scheme exists and examine whether nodes that classify the channel as belonging to the same class also exhibit strong cross-correlation in terms of the RSSI time series they independently observe. In effect, we are studying how the agreement of nodes, e.g., via consensus, on the class of a channel can be linked to the cross-correlation statistic and to what extent. We find that the particular class impacts the degree to which we can confidently claim that the channel observed independently by each node, and classified to belong to the same class, indeed behaves the same way.

Posters
Paper Nr: 66
Title:

Compensation of the Antenna Polarization Misalignment in the RSSI Estimation

Authors:

D. Polese, L. Pazzini, A. Minotti, L. Maiolo and A. Pecora

Abstract: The diffusion of wireless sensor networks has allowed the development of a plethora of indoor localization algorithms based on these technologies. Also if several radio signal features have been exploited in order to estimate the position, the Received Signal Strength (RSS) is probably the most used. RSS depends, in addition to the distance, also on multipath transmission, barriers and non-idealities of antenna. Differences between ideal and real omnidirectional transmission patterns or polarization angle misalignment can strongly affect the RSS value impairing the following localization algorithm. In this paper, an algorithm to compensate the dependence of the RSS on the angle among the antennas is proposed and tested. The experimental results prove the goodness of the approach and the possibility of using this algorithm to minimize the dependence of RSS from the tilting angle among the nodes of a localization sensor network.

Paper Nr: 69
Title:

Radio-Interferometric Object Trajectory Estimation

Authors:

Gergely Zachár and Gyula Simon

Abstract: In this paper a novel radio-interferometric object trajectory estimation method is proposed, which can be used to track moving objects. The system utilizes a low number of fixed infrastructure nodes equipped with radio transceivers, and the tracked object also carries a simple transceiver. Selected transmitter infrastructure nodes produce interference signals at the fixed infrastructure receivers and the tracked receiver. Transmitter and receiver roles are rotated, thus multiple interference signals are produced, which is measured by synchronized receiver pairs. Measurements are then compared to pre-computed phase maps while the object is moving. During object movement the system resolves position ambiguities and the exact object trajectory is determined. The performance of the proposed method is illustrated by simulation examples and real measurements.

Area 5 - Signal Processing

Posters
Paper Nr: 11
Title:

A New Covariance-assignment State Estimator in the Presence of Intermittent Observation Losses

Authors:

Sangho Ko, Seungeun Kang and Jihyoung Cha

Abstract: This paper introduces an improved linear state estimator which directly assigns the error covariance in an environment where the measured data are intermittently missing. Since this new estimator uses an additional information indicating whether each observation is successfully measured, represented as a bernoulli random variable in the measurement equation, it naturally outperforms the previous type of covariance-assignment estimators which do not rely upon such information. This fact is proved by comparing the magnitude of the state error covariances via the monotonicity of the Riccati difference equation, and demonstrated using a numerical example.

Area 6 - Obstacles

Short Papers
Paper Nr: 9
Title:

RAID’ing Wireless Sensor Networks - Data Recovery for Node Failures

Authors:

Ailin Zhou and Mario A. Nascimento

Abstract: In wireless sensor networks (WSNs), sensor nodes may fail due to energy depletion or physical damage. To avoid data loss and incomplete query results when node failure takes place, we propose a node failure recovery scheme which can recover the data of failed nodes. Our scheme incorporates data redundancy and distributes, in an effective and storage efficient manner, redundant information among nodes in the WSN. When a node fails, the remaining functioning sensors can use the redundant information regarding the failed node to recover its data. An energy consumption model is also presented for calculating the communication cost of the proposed scheme. We use simulations to compare the network lifetime with and without recovery being involved, where the network lifetime is defined as the time that a node failure is observed and its data can not be recovered. Our experimental results show that the recovery scheme can yield a lifetime up to three times longer than that of no-recovery scheme.

Posters
Paper Nr: 6
Title:

Evaluation of Energy Efficiency of Aggregation in WSNs using Petri Nets

Authors:

Ákos Milánkovich, Gergely Ill, Károly Lendvai, Sándor Imre and Sándor Szabó

Abstract: Energy efficiency is one of the key issues of wireless sensor networks. Aggregation of packets may increase significantly the lifetime of batteries in exchange for some variations in delay. In this paper we have investigated how to determine the optimal amount of packets gathered for aggregation that minimizes the energy consumption of the whole multi-hop network assuming predefined boundary conditions for the delay. To achieve this goal, appropriate models were created to calculate the energy consumption and delay, where we exploited the modelling capabilities of generalized stochastic Petri nets. Using these models, the impact of aggregation was analysed for various test cases. We examined how a network behaves in case of ideal, low and high BERs and investigated how different FEC coding schemes influence the energy consumption. Based on these results, we evaluated the properties of aggregation. We will show, that in case of a good quality radio channel (with low BER) it is not recommended to use FEC codes to optimize for energy consumption. In case of high aggregation numbers and high BER without the use of FEC the consumed energy converges to infinity. The simulation results show that using the delay as a constraint can narrow down the search for the minimal energy consumption of aggregation number vectors.

Area 7 - Applications and Uses

Full Papers
Paper Nr: 23
Title:

Portable Sensing of Organic Vapours based on a Single Semiconductor Sensor

Authors:

Andrzej Szczurek and Monika Maciejewska

Abstract: A notable need for lightweight, simple-to-use portable gas analysers with facilities aimed at wide range of applications is observed in the market of measuring instruments today. In this work, a concept of portable sensing of organic vapours is presented. As the most reliable, the semiconductor gas sensor technology was chosen. However, due to high power consumption of this kind of sensors only a single sensor option is currently feasible for the portable device. In view of partial selectivity of the metal oxide based gas sensors, the unsatisfactory analytical abilities of the device could be anticipated. But, we showed that a single semiconductor gas sensor may be used for identification and quantification of the organic compounds vapours. In our solution, this goal is accomplished by applying active gas sampling. It was demonstrated that variable exposure conditions of a sensor, which are induced by the gas flow, allow for obtaining the sensor signal that has high information content. It is sufficient to characterize the test gases qualitatively and quantitatively. The achieved accuracy is very good for a screening device.

Short Papers
Paper Nr: 34
Title:

Multiple Gas Sensors System for Environmental and Air Quality Assessments - A Way to Perform Environmental Monitoring in Smart Cities

Authors:

Zaher Al Barakeh, Valérie Delbart and Fabien Bonnet

Abstract: In recent years, people are getting more and more concerned with air quality and other environmental nuisance. Whether it’s indoors or outdoors, humans are getting more sensitive to the issue. Implementing a more accessible commercial low cost environmental surveillance systems have proven to be a rapidly growing solution. Therefore, we are specially focused on environmental quality measurements, integrating environmental and gas sensors in wireless communicating systems in order to provide a wide-range monitoring solutions suitable for several environmental case study. We have also created different indicators which convey the wellbeing state in encountered situations where user can rely on these indicators to assess their environment quality. In this work we present a framework for monitoring real time particulate matter evolution in a construction site and the implementation of different acoustic noise measurement systems for mapping the noise evolution in a chosen city. Achieved results show the effectiveness of such systems in nuisance detection and qualifying living environments.

Paper Nr: 44
Title:

Maximizing the Relevant Diversity of Social Swarming Information

Authors:

Peter Terlecky, Yurong Jiang, Xing Xu, Amotz Bar-Noy and Ramesh Govindan

Abstract: In social swarming applications, users are equipped with smartphones and generate data on specific tasks in the form pictures, video, audio, text. A central commander would like to gain access to data relevant to a particular query. Which data wirelessly uploaded to the commander maximizes the amount of diverse information received subject to a bandwidth constraint? We model such a problem in two distinct ways. It is first modeled as a maximum coverage with group budget constraints problem and then as a variant of the maximum edge-weighted clique problem. It is shown that the algorithm for the maximum coverage model outperforms a heuristic for the clique-based model theoretically and practically, with both performing very well experimentally compared to an upper bound benchmark.

Paper Nr: 49
Title:

A Minimal Cost, Soil Moisture Measurement System - Logging Wenner Array Resistivity with a Microcontroller for Less than 10 Euros

Authors:

Martin J. Oates, Angel L. Vazquez de Leon and Neil M. Edwards

Abstract: Where water is a scarce resource, efficient use of irrigation systems is an absolute requirement for crop management. Whilst there are many commercial systems available on the market, units typically cost hundreds of dollars or are lacking in basic data-logging capabilities. This paper describes results from trials of a minimal cost microcontroller based monitoring system designed for large scale deployment or highly cost sensitive monitoring. The system can easily be expanded to meet differing socio-economic situations.

Paper Nr: 53
Title:

Improving GSM-based Sheep Tracking - Using a Cluster-based Multi-hop Approach

Authors:

Ragnar Stølsmark and Erlend Tøssebro

Abstract: This paper presents a novel sheep tracking algorithm. The current market leading solution, Telespor, performs poorly in situations with low GSM coverage. The algorithm presented here tries to improve the performance of Telespor in low GSM coverage scenarios by using a multi-hop approach for data retrieval. It also uses a cluster-based technique to improve cost and energy consumption. To test the algorithm, simulations were performed based on data collected from a flock of more than 450 sheep. These simulations show that the new algorithm outperforms Telespor in scenarios with low GSM coverage. It also show that it is possible to get a good ratio of successful updates even with a relatively small amount of full feature nodes. This indicates that the algorithm is an improvement also in terms of cost and energy consumption.

Paper Nr: 73
Title:

Automated Personalized Goal-setting in an Activity Coaching Application

Authors:

Miriam Cabrita, Harm op den Akker, Reinoud Achterkamp, Hermie Hermens and Miriam Vollenbroek-Hutten

Abstract: The ageing population and the increase in sedentary lifestyles of knowledge workers has led to increasing concerns about the physical activity habits of the European population. Pervasive technologies and theories of behavioral change are being combined in an effort to promote physical activity. The Activity Coach is an example of one such system. Whereas the previous version of the Activity Coach set a fixed and permanent daily goal, in this work we describe the addition of an automatically adaptive goal-setting feature to this existing system. With the new feature, the daily goals for physical activity are set based on the user’s routine, contributing to the personalization of the system. A technical evaluation was performed to test the system’s adaptation to the user’s routine. Additionally, a conversion factor between a unit of energy expenditure and number of steps was determined. The evaluation indicates that our method of goal-setting provides more challenging but still attainable goals when compared to the previous version. Additional evaluations are recommended to evaluate the user’s perception and effects on physical activity behavior change of this new feature. The results of this research are implemented in the existing Activity Coach and will be used in future patient evaluations.

Paper Nr: 74
Title:

Improving Context-aware Applications for the Well-being Domain - Model-driven Design Guided by Medical Knowledge

Authors:

Steven Bosems and Marten van Sinderen

Abstract: Computing applications for among others well-being and health become increasingly advanced as a result of their sensor-based awareness of the context in which they are used. Context-aware applications have the potential of providing enriched services to their users, i.e. services that are appropriate for the context at hand. A challenge for the design of context-aware applications is to identify and develop service enrichments which are effective and useful while not being overly complex and costly. It is hard to imagine, both for the designer and end-user, all possible relevant contexts and best possible corresponding enriched services. An enriched service which is not appropriate for the context at hand can irritate or even harm the user, and (eventually) leads to avoiding the use of the service. This paper discusses a model-driven approach that incorporates domain knowledge concerning the causal relationship between context factors and human conditions. We believe that such an approach facilitates the identification and development of appropriate sensor-based context-aware services. We focus on context-aware applications for the well-being domain.

Posters
Paper Nr: 3
Title:

A Task Allocation Middleware for Wireless Sensor Networks in a Multi-Agent Environment

Authors:

Luca Caviglione, Mauro Coccoli and Alberto Grosso

Abstract: This paper presents the design of a task allocation middleware for the coordination of a Wireless Sensor Network (WSN) of embedded devices. Acquisition and distribution of new tasks are performed via a multi-agent system, while service oriented principles are used to handle data gathered from the field. Also, an ad-hoc component has been designed to reduce the impact of heterogeneous networks (e.g., long-haul satellite links). Lastly, we showcase an experimental setup to prove the effectiveness of the approach when used to enhance a forest fire prevention application.

Paper Nr: 15
Title:

Integration of a Wireless Sensor-actuator Network and an FPGA for Intelligent Inhabited Environments

Authors:

Javier Echanobe, Estibaliz Asua and Inés del Campo

Abstract: Wireless Sensor and Actuator Networks together with processing elements named intelligent agents are achieving great importance in environmental control. The trend in this field points to implement small, low power, low cost and fast systems, which is in general, hard to achieve. In this paper, an electronic system that consists of several sensors and actuators and a FPGA endowed with Neurofuzzy based intelligent algorithms is presented. The purpose of this work is to demonstrate the effectiveness of the FPGA to provide intelligence to a Wireless Sensor and Actuator Networks. As example of application, a system which acts over a floor lamp intensity and an opening of a window in an autonomous way is presented. This autonomous action is calculated by the FPGA based on several parameters provided by the network (temperature, humidity and luminosity). By integrating the low power WSAN and the FPGA-based Intelligent Agent, a small, low power, low cost high-performance intelligent environment system is achieved.

Paper Nr: 24
Title:

Indoor Air Quality Monitoring Network Design based on Uncertainty and Mutual Information

Authors:

Monika Maciejewska and Andrzej Szczurek

Abstract: Poor quality of indoor air is an important problem in the world today. Although credible methodology of indoor air quality (IAQ) assessment has not been developed so far, the provision of relevant information is necessary for taking actions towards its control. The currently accepted compromise is to focus on the measurable physical and chemical parameters of indoor air as the basis for judging the thermal comfort and chemical IAQ. These quantities show spatial and temporal variability, therefore infrequent or single location measurements are usually insufficient for gaining an outlook of indoor air quality. Therefore, there are preferred multipoint, continuous measurements. They may be realized by the indoor air quality monitoring system. An interesting option for such system is a sensor network. This work presents a statistical method of choosing the location of the nodes of the sensor network for indoor air quality monitoring. The method is based on the information measures. The novelty of the presented approach consists in basing the nodes selection on the information content of the data provided by the sensor network in discrete time moments. The method was demonstrated as applied to the revision of an indoor air quality monitoring network in an office building.

Paper Nr: 26
Title:

Smart Fabrication of Robotic Systems - A Project with University Students

Authors:

Vanessa Nickel, Pablo Ottersbach, Robert Reichert and Michael Schäfer

Abstract: This paper describes the progression of new construction technologies to rapid prototype multicopters. Based on ideas of the growing maker-community, university students used 3D-printing and laser-cutting technologies to build copters with individual features. In this case a flight without visual contact should be realised by mounting a camera in front of the copter. Both technologies were used in competition and the better requirements satisfying copter was built.

Paper Nr: 28
Title:

The Intelligent Container - A Cognitive Sensor Net for Fruit Logistics

Authors:

Walter Lang, Steffen Janßen and Reiner Jedermann

Abstract: The Intelligent Container is a wireless sensor network for the control of perishable goods such as vegetables, fruits or meat. Several data interpretation tools are implemented in the sensor nodes. These can estimate temperature related quality losses, supervise sensor deployment and measurement intervals, and detect malfunctioning sensors. In order to retrieve information about the ripening directly from the transported fruits, the ripening indicator ethylene is detected using a newly developed highly sensitive and selective gas measurement system. The intelligent container allows the realisation of the new logistic paradigm of dynamic FEFO (First Expire First Out): the remaining life time—estimated shelf life—of the transported fruits is used to control the logistic process. This paper describes the developments performed on the Intelligent Container by the University of Bremen and its partners.