Open AccessArticle
Querying on Federated Sensor Networks
J. Sens. Actuator Netw. 2016, 5(3), 14; doi:10.3390/jsan5030014 -
Abstract
A Federated Sensor Network (FSN) is a network of geographically distributed Wireless Sensor Networks (WSNs) called islands. For querying on an FSN, we introduce the Layered Federated Sensor Network (L-FSN) Protocol. For layered management, L-FSN provides communication among islands by its inter-island [...] Read more.
A Federated Sensor Network (FSN) is a network of geographically distributed Wireless Sensor Networks (WSNs) called islands. For querying on an FSN, we introduce the Layered Federated Sensor Network (L-FSN) Protocol. For layered management, L-FSN provides communication among islands by its inter-island querying protocol by which a query packet routing path is determined according to some path selection policies. L-FSN allows autonomous management of each island by island-specific intra-island querying protocols that can be selected according to island properties. We evaluate the applicability of L-FSN and compare the L-FSN protocol with various querying protocols running on the flat federation model. Flat federation is a method to federate islands by running a single querying protocol on an entire FSN without distinguishing communication among and within islands. For flat federation, we select a querying protocol from geometrical, hierarchical cluster-based, hash-based, and tree-based WSN querying protocol categories. We found that a layered federation of islands by L-FSN increases the querying performance with respect to energy-efficiency, query resolving distance, and query resolving latency. Moreover, L-FSN’s flexibility of choosing intra-island querying protocols regarding the island size brings advantages on energy-efficiency and query resolving latency. Full article
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Open AccessArticle
An Experimental Comparison of Radio Transceiver and Transceiver-Free Localization Methods
J. Sens. Actuator Netw. 2016, 5(3), 13; doi:10.3390/jsan5030013 -
Abstract
This paper presents an experimental performance assessment for localization systems using received signal strength (RSS) measurements from a wireless sensor network. In this experimental study, we compare two types of model-based localization methods: transceiver-based localization, which locates objects using RSS from transmitters [...] Read more.
This paper presents an experimental performance assessment for localization systems using received signal strength (RSS) measurements from a wireless sensor network. In this experimental study, we compare two types of model-based localization methods: transceiver-based localization, which locates objects using RSS from transmitters to receivers at known locations; and transceiver-free localization, which estimates location by using RSS changes on known-location nodes caused by objects. We evaluate their performance using three sets of experiments with different environmental conditions. Our performance analysis shows that transceiver-free localization methods are generally more accurate than transceiver-based localization methods for a wireless sensor network with high node density. Full article
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Open AccessArticle
A Cooperative MAC Protocol for a M2M Heterogeneous Area Network
J. Sens. Actuator Netw. 2016, 5(3), 12; doi:10.3390/jsan5030012 -
Abstract
With the increasing demand of Machine to Machine (M2M) communications and Internet of Things (IoT) services it is necessary to develop a new network architecture and protocols to support cost effective, distributed computing systems. Generally, M2M and IoT applications serve a large [...] Read more.
With the increasing demand of Machine to Machine (M2M) communications and Internet of Things (IoT) services it is necessary to develop a new network architecture and protocols to support cost effective, distributed computing systems. Generally, M2M and IoT applications serve a large number of intelligent devices, such as sensors and actuators, which are distributed over large geographical areas. To deploy M2M communication and IoT sensor nodes in a cost-effective manner over a large geographical area, it is necessary to develop a new network architecture that is cost effective, as well as energy efficient. This paper presents an IEEE 802.11 and IEEE 802.15.4 standards-based heterogeneous network architecture to support M2M communication services over a wide geographical area. For the proposed heterogeneous network, we developed a new cooperative Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) medium access control (MAC) protocol to transmit packets using a shared channel in the 2.4 GHz ISM band. One of the key problems of the IEEE 802.11/802.15.4 heterogeneous network in a dense networking environment is the coexistence problem in which the two protocols interfere with each other causing performance degradation. This paper introduces a cooperative MAC protocol that utilizes a new signaling technique known as the Blank Burst (BB) to avoid the coexistence problem. The proposed MAC protocol improves the network QoS of M2M area networks. The developed network architecture offers significant energy efficiency, and operational expenditure (OPEX) and capital expenditure (CAPEX) advantages over 3G/4G cellular standards-based wide area networks. Full article
Open AccessArticle
Novel Simulation Approaches for Smart Grids
J. Sens. Actuator Netw. 2016, 5(3), 11; doi:10.3390/jsan5030011 -
Abstract
The complexity of the power grid, in conjunction with the ever increasing demand for electricity, creates the need for efficient analysis and control of the power system. The evolution of the legacy system towards the new smart grid intensifies this need due [...] Read more.
The complexity of the power grid, in conjunction with the ever increasing demand for electricity, creates the need for efficient analysis and control of the power system. The evolution of the legacy system towards the new smart grid intensifies this need due to the large number of sensors and actuators that must be monitored and controlled, the new types of distributed energy sources that need to be integrated and the new types of loads that must be supported. At the same time, integration of human-activity awareness into the smart grid is emerging and this will allow the system to monitor, share and manage information and actions on the business, as well as the real world. In this context, modeling and simulation is an invaluable tool for system behavior analysis, energy consumption estimation and future state prediction. In this paper, we review current smart grid simulators and approaches for building and user behavior modeling, and present a federated smart grid simulation framework, in which building, control and user behavior modeling and simulation are decoupled from power or network simulators and implemented as discrete components. This framework enables evaluation of the interactions between the communication infrastructure and the power system taking into account the human activities, which are at the focus of emerging energy-related applications that aim to shape user behavior. Validation of the key functionality of the proposed framework is also presented. Full article
Open AccessArticle
A Privacy-by-Design Contextual Suggestion System for Tourism
J. Sens. Actuator Netw. 2016, 5(2), 10; doi:10.3390/jsan5020010 -
Abstract
We focus on personal data generated by the sensors and through the everyday usage of smart devices and take advantage of these data to build a non-invasive contextual suggestion system for tourism. The system, which we call Pythia, exploits the computational capabilities [...] Read more.
We focus on personal data generated by the sensors and through the everyday usage of smart devices and take advantage of these data to build a non-invasive contextual suggestion system for tourism. The system, which we call Pythia, exploits the computational capabilities of modern smart devices to offer high quality personalized POI (point of interest) recommendations. To protect user privacy, we apply a privacy by design approach within all of the steps of creating Pythia. The outcome is a system that comprises important architectural and operational innovations. The system is designed to process sensitive personal data, such as location traces, browsing history and web searches (query logs), to automatically infer user preferences and build corresponding POI-based user profiles. These profiles are then used by a contextual suggestion engine to anticipate user choices and make POI recommendations for tourists. Privacy leaks are minimized by implementing an important part of the system functionality at the user side, either as a mobile app or as a client-side web application, and by taking additional precautions, like data generalization, wherever necessary. As a proof of concept, we present a prototype that implements the aforementioned mechanisms on the Android platform accompanied with certain web applications. Even though the current prototype focuses only on location data, the results from the evaluation of the contextual suggestion algorithms and the user experience feedback from volunteers who used the prototype are very positive. Full article
Open AccessArticle
Group Authentication Scheme for Neighbourhood Area Networks (NANs) in Smart Grids
J. Sens. Actuator Netw. 2016, 5(2), 9; doi:10.3390/jsan5020009 -
Abstract
A Neighbourhood Area Network is a functional component of the Smart Grid that interconnects the end user domain with the Energy Services Provider (ESP) domain. It forms the “edge” of the provider network, interconnecting homes instrumented with Smart Meters (SM) with the [...] Read more.
A Neighbourhood Area Network is a functional component of the Smart Grid that interconnects the end user domain with the Energy Services Provider (ESP) domain. It forms the “edge” of the provider network, interconnecting homes instrumented with Smart Meters (SM) with the ESP. The SM is a dual interface, wireless communication device through which information is transacted across the user (a home) and ESP domains. The security risk to the ESP increases since the components within the home, interconnected to the ESP via the SM, are not managed by the ESP. Secure operation of the SM is a necessary requirement. The SM should be resilient to attacks, which might be targeted either directly or via the network in the home. This paper presents and discusses a security scheme for groups of SMs in a Neighbourhood Area Network that enable entire groups to authenticate themselves, rather than one at a time. The results show that a significant improvement in terms of resilience against node capture attacks, replay attacks, confidentiality, authentication for groups of SMs in a NAN that enable entire groups to authenticate themselves, rather than one at a time. Full article
Open AccessArticle
Data Dissemination in Mobile Social Networks with the Acknowledgment Feedback
J. Sens. Actuator Netw. 2016, 5(2), 8; doi:10.3390/jsan5020008 -
Abstract
Most existing dissemination schemes in Mobile Social Networks (MSNs) only consider the data dissemination. However, there are two types of messages: data and the control message (i.e., acknowledgment) in MSNs, and receiving acknowledgment is very important in many applications (e.g., [...] Read more.
Most existing dissemination schemes in Mobile Social Networks (MSNs) only consider the data dissemination. However, there are two types of messages: data and the control message (i.e., acknowledgment) in MSNs, and receiving acknowledgment is very important in many applications (e.g., the mobile trade and the incentive mechanism). In order to maximize the desired message delivery ratio, we have to identify the priority of each message in the network during the limited contact opportunity. Therefore, we propose a generic priority-based compare-split routing scheme, which proves to be the optimal buffer exchange strategy. During each contact opportunity, relays compare their forwarding abilities to different destinations based on two types of criteria: the contact probability and the social status. Ideally, each relay keeps the messages whose destinations meet the current relay frequently. Then, an adaptive priority-based exchange scheme, which considers the priority within each type of messages and the relative priority between two types of messages, is proposed to exchange the most benefit messages. The effectiveness of our scheme is verified through extensive simulations in synthetic and real traces. Full article
Open AccessArticle
Business Model Design and Architecture for the Internet of Everything
J. Sens. Actuator Netw. 2016, 5(2), 7; doi:10.3390/jsan5020007 -
Abstract
Smart devices and cyber-physical systems, which are interconnected to IT systems and services, form the basis for the arising Internet of Everything, opening up new economic opportunities for its participants and users beyond its technological aspects and challenges. While today’s e-business scenarios [...] Read more.
Smart devices and cyber-physical systems, which are interconnected to IT systems and services, form the basis for the arising Internet of Everything, opening up new economic opportunities for its participants and users beyond its technological aspects and challenges. While today’s e-business scenarios are mostly dominated by a few centralized online platforms, future business models, which will be feasible for the Internet of Everything, need to address special requirements. Such business models, e.g., leveraging the possibilities of smart cities, need to cope with arbitrary combinations of products and services orchestrated into complex products in a highly distributed and dynamic environment. Furthermore, these arbitrary combinations are influenced by real-time context information derived from sensor networks or IT systems, as well as the users’ requirements and preferences. The complexity of finding the optimal product/service combination overstrains users and leads to decisions according to the principle of adverse selection (i.e., choosing good enough instead of optimal). Such e-business models require an appropriate underlying value generation architecture that supports users in this process. In this paper, we develop a business model that addresses these problems. In addition, we present the Distributed Market Spaces (DMS) software-system architecture as a possible implementation, which enables the aforementioned decentralized and context-centric e-business scenario and leverages the commercial possibilities of smart cities. Full article
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Open AccessArticle
Routing Protocols for Delay Tolerant Networks: A Reference Architecture and a Thorough Quantitative Evaluation
J. Sens. Actuator Netw. 2016, 5(2), 6; doi:10.3390/jsan5020006 -
Abstract
In this paper, we propose a reference architecture for Delay-Tolerant Networking (DTN) routing protocols and a thorough quantitative evaluation of many protocols proposed in the literature. We categorize DTN protocols according to their use of the three techniques that are the key [...] Read more.
In this paper, we propose a reference architecture for Delay-Tolerant Networking (DTN) routing protocols and a thorough quantitative evaluation of many protocols proposed in the literature. We categorize DTN protocols according to their use of the three techniques that are the key elements of our reference architecture: queue management, forwarding and replication. Queue management orders and manages the messages in the node’s buffer; forwarding selects the messages to be delivered when there is a contact; and finally, replication bounds the number of replicas in the network. Contrary to most previous papers, where either only qualitative comparisons have been presented or only a single category of protocols has been analyzed, in our work, we discuss the results of our experimental activity on many of the DTN protocols in the literature. Our results, which have been obtained both using synthetic and real mobility traces, show that an effective combination of the proposed techniques can significantly improve the performance of the protocols in terms of delivery ratio, overhead and delay. Full article
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Open AccessArticle
Dealing with Data Quality in Smart Home Environments—Lessons Learned from a Smart Grid Pilot
J. Sens. Actuator Netw. 2016, 5(1), 5; doi:10.3390/jsan5010005 -
Abstract
Over the last years, we have witnessed increasing interconnection between the physical and digital world. The so called Internet of Things (IoT) is becoming more and more a reality in application domains like manufacturing, mobile computing, transportation, and many others. However, despite [...] Read more.
Over the last years, we have witnessed increasing interconnection between the physical and digital world. The so called Internet of Things (IoT) is becoming more and more a reality in application domains like manufacturing, mobile computing, transportation, and many others. However, despite promising huge potential, the application domain of smart homes is still at its infancy and lags behind other fields of IoT. A deeper understanding of this type of techno-human system is required to make this vision a reality. In this paper, we report findings from a three year pilot that sheds light on the challenges of leveraging IoT technology in the home environment. In particular, we provide details on data quality issues in real-world deployments. That is, we analyze application level data for errors in measurements as well as issues in the end-to-end communication. Understanding what data errors to expect is crucial for understanding the smart building domain and paramount for building successful applications. With our work, we provide insights in a domain of IoT that has tremendous growth potential and help researchers as well as practitioners to better account for the data characteristics of smart homes. Full article
Open AccessArticle
A Cooja-Based Tool for Coverage and Lifetime Evaluation in an In-Building Sensor Network
J. Sens. Actuator Netw. 2016, 5(1), 4; doi:10.3390/jsan5010004 -
Abstract
Contiki’s Cooja is a very popular wireless sensor network (WSN) simulator, but it lacks support for modelling sensing coverage, focusing instead on network connectivity and protocol performance. However, in practice, it is the ability of a sensor network to provide a satisfactory [...] Read more.
Contiki’s Cooja is a very popular wireless sensor network (WSN) simulator, but it lacks support for modelling sensing coverage, focusing instead on network connectivity and protocol performance. However, in practice, it is the ability of a sensor network to provide a satisfactory level of coverage that defines its ultimate utility for end-users. We introduce WSN-Maintain, a Cooja-based tool for coverage and network lifetime evaluation in an in-building WSN. To extend the network lifetime, but still maintain the required quality of coverage, the tool finds coverage redundant nodes, puts them to sleep and automatically turns them on when active nodes fail and coverage quality decreases. WSN-Maintain together with Cooja allow us to evaluate different approaches to maintain coverage. As use cases to the tool, we implement two redundant node algorithms: greedy-maintain, a centralised algorithm, and local-maintain, a localised algorithm to configure the initial network and to turn on redundant nodes. Using data from five real deployments, we show that our tool with simple redundant node algorithms and reading correlation can improve energy efficiency by putting more nodes to sleep. Full article
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Open AccessFeature PaperReview
Social Internet of Vehicles for Smart Cities
J. Sens. Actuator Netw. 2016, 5(1), 3; doi:10.3390/jsan5010003 -
Abstract
Digital devices are becoming increasingly ubiquitous and interconnected. Their evolution to intelligent parts of a digital ecosystem creates novel applications with so far unresolved security issues. A particular example is a vehicle. As vehicles evolve from simple means of transportation to smart [...] Read more.
Digital devices are becoming increasingly ubiquitous and interconnected. Their evolution to intelligent parts of a digital ecosystem creates novel applications with so far unresolved security issues. A particular example is a vehicle. As vehicles evolve from simple means of transportation to smart entities with new sensing and communication capabilities, they become active members of a smart city. The Internet of Vehicles (IoV) consists of vehicles that communicate with each other and with public networks through V2V (vehicle-to-vehicle), V2I (vehicle-to-infrastructure) and V2P (vehicle-to-pedestrian) interactions, which enables both the collection and the real-time sharing of critical information about the condition on the road network. The Social Internet of Things (SIoT) introduces social relationships among objects, creating a social network where the participants are not humans, but intelligent objects. In this article, we explore the concept of the Social Internet of Vehicles (SIoV), a network that enables social interactions both among vehicles and among drivers. We discuss technologies and components of the SIoV, possible applications and issues of security, privacy and trust that are likely to arise. Full article
Open AccessArticle
Enhanced Distributed Dynamic Skyline Query for Wireless Sensor Networks
J. Sens. Actuator Netw. 2016, 5(1), 2; doi:10.3390/jsan5010002 -
Abstract
Dynamic skyline query is one of the most popular and significant variants of skyline query in the field of multi-criteria decision-making. However, designing a distributed dynamic skyline query possesses greater challenge, especially for the distributed data centric storage within wireless sensor networks [...] Read more.
Dynamic skyline query is one of the most popular and significant variants of skyline query in the field of multi-criteria decision-making. However, designing a distributed dynamic skyline query possesses greater challenge, especially for the distributed data centric storage within wireless sensor networks (WSNs). In this paper, a novel Enhanced Distributed Dynamic Skyline (EDDS) approach is proposed and implemented in Disk Based Data Centric Storage (DBDCS) architecture. DBDCS is an adaptation of magnetic disk storage platter consisting tracks and sectors. In DBDCS, the disc track and sector analogy is used to map data locations. A distance based indexing method is used for storing and querying multi-dimensional similar data. EDDS applies a threshold based hierarchical approach, which uses temporal correlation among sectors and sector segments to calculate a dynamic skyline. The efficiency and effectiveness of EDDS has been evaluated in terms of latency, energy consumption and accuracy through a simulation model developed in Castalia. Full article
Open AccessEditorial
Acknowledgement to Reviewers of JSAN in 2015
J. Sens. Actuator Netw. 2016, 5(1), 1; doi:10.3390/jsan5010001 -
Abstract The editors of JSAN would like to express their sincere gratitude to the following reviewers for assessing manuscripts in 2015. [...] Full article
Open AccessArticle
The Efficacy of Epidemic Algorithms on Detecting Node Replicas in Wireless Sensor Networks
J. Sens. Actuator Netw. 2015, 4(4), 378-409; doi:10.3390/jsan4040378 -
Abstract
A node replication attack against a wireless sensor network involves surreptitious efforts by an adversary to insert duplicate sensor nodes into the network while avoiding detection. Due to the lack of tamper-resistant hardware and the low cost of sensor nodes, launching replication [...] Read more.
A node replication attack against a wireless sensor network involves surreptitious efforts by an adversary to insert duplicate sensor nodes into the network while avoiding detection. Due to the lack of tamper-resistant hardware and the low cost of sensor nodes, launching replication attacks takes little effort to carry out. Naturally, detecting these replica nodes is a very important task and has been studied extensively. In this paper, we propose a novel distributed, randomized sensor duplicate detection algorithm called Discard to detect node replicas in group-deployed wireless sensor networks. Our protocol is an epidemic, self-organizing duplicate detection scheme, which exhibits emergent properties. Epidemic schemes have found diverse applications in distributed computing: load balancing, topology management, audio and video streaming, computing aggregate functions, failure detection, network and resource monitoring, to name a few. To the best of our knowledge, our algorithm is the first attempt at exploring the potential of this paradigm to detect replicas in a wireless sensor network. Through analysis and simulation, we show that our scheme achieves robust replica detection with substantially lower communication, computational and storage requirements than prior schemes in the literature. Full article
Open AccessFeature PaperArticle
Colorful Textile Antennas Integrated into Embroidered Logos
J. Sens. Actuator Netw. 2015, 4(4), 371-377; doi:10.3390/jsan4040371 -
Abstract
We present a new methodology to create colorful textile antennas that can be embroidered within logos or other aesthetic shapes. Conductive threads (e-threads) have already been used in former embroidery unicolor approaches as attributed to the corresponding conductive material, viz. silver [...] Read more.
We present a new methodology to create colorful textile antennas that can be embroidered within logos or other aesthetic shapes. Conductive threads (e-threads) have already been used in former embroidery unicolor approaches as attributed to the corresponding conductive material, viz. silver or copper. But so far, they have not been adapted to ‘print’ colorful textile antennas. For the first time, we propose an approach to create colorful electronic textile shapes. In brief, the embroidery process uses an e-thread in the bobbin case of the sewing machine to embroider the antenna on the back side of the garment. Concurrently, a colorful assistant yarn is threaded through the embroidery needle of the embroidery machine and used to secure or ‘couch’ the e-threads onto the fabric. In doing so, a colorful shape is generated on the front side of the garment. The proposed antennas can be unobtrusively integrated into clothing or other accessories for a wide range of applications (e.g., wireless communications, Radio Frequency IDentification, sensing). Full article
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Open AccessArticle
Critical Infrastructure Surveillance Using SecureWireless Sensor Networks
J. Sens. Actuator Netw. 2015, 4(4), 336-370; doi:10.3390/jsan4040336 -
Abstract
In this work, a secure wireless sensor network (WSN) for the surveillance, monitoring and protection of critical infrastructures was developed. To guarantee the security of the system, the main focus was the implementation of a unique security concept, which includes both security [...] Read more.
In this work, a secure wireless sensor network (WSN) for the surveillance, monitoring and protection of critical infrastructures was developed. To guarantee the security of the system, the main focus was the implementation of a unique security concept, which includes both security on the communication level, as well as mechanisms that ensure the functional safety during its operation. While there are many theoretical approaches in various subdomains of WSNs—like network structures, communication protocols and security concepts—the construction, implementation and real-life application of these devices is still rare. This work deals with these aforementioned aspects, including all phases from concept-generation to operation of a secure wireless sensor network. While the key focus of this paper lies on the security and safety features of the WSN, the detection, localization and classification capabilities resulting from the interaction of the nodes’ different sensor types are also described. Full article
Open AccessArticle
Lesson Learned from Collecting Quantified Self Information via Mobile and Wearable Devices
J. Sens. Actuator Netw. 2015, 4(4), 315-335; doi:10.3390/jsan4040315 -
Abstract
The ubiquity and affordability of mobile and wearable devices has enabled us to continually and digitally record our daily life activities. Consequently, we are seeing the growth of data collection experiments in several scientific disciplines. Although these have yielded promising results, mobile [...] Read more.
The ubiquity and affordability of mobile and wearable devices has enabled us to continually and digitally record our daily life activities. Consequently, we are seeing the growth of data collection experiments in several scientific disciplines. Although these have yielded promising results, mobile and wearable data collection experiments are often restricted to a specific configuration that has been designed for a unique study goal. These approaches do not address all the real-world challenges of “continuous data collection” systems. As a result, there have been few discussions or reports about such issues that are faced when “implementing these platforms” in a practical situation. To address this, we have summarized our technical and user-centric findings from three lifelogging and Quantified Self data collection studies, which we have conducted in real-world settings, for both smartphones and smartwatches. In addition to (i) privacy and (ii) battery related issues; based on our findings we recommend further works to consider (iii) implementing multivariate reflection of the data; (iv) resolving the uncertainty and data loss; and (v) consider to minimize the manual intervention required by users. These findings have provided insights that can be used as a guideline for further Quantified Self or lifelogging studies. Full article
Open AccessArticle
On Optimal Multi-Sensor Network Configuration for 3D Registration
J. Sens. Actuator Netw. 2015, 4(4), 293-314; doi:10.3390/jsan4040293 -
Abstract
Multi-sensor networks provide complementary information for various taskslike object detection, movement analysis and tracking. One of the important ingredientsfor efficient multi-sensor network actualization is the optimal configuration of sensors.In this work, we consider the problem of optimal configuration of a network of [...] Read more.
Multi-sensor networks provide complementary information for various taskslike object detection, movement analysis and tracking. One of the important ingredientsfor efficient multi-sensor network actualization is the optimal configuration of sensors.In this work, we consider the problem of optimal configuration of a network of coupledcamera-inertial sensors for 3D data registration and reconstruction to determine humanmovement analysis. For this purpose, we utilize a genetic algorithm (GA) based optimizationwhich involves geometric visibility constraints. Our approach obtains optimal configurationmaximizing visibility in smart sensor networks, and we provide a systematic study usingedge visibility criteria, a GA for optimal placement, and extension from 2D to 3D.Experimental results on both simulated data and real camera-inertial fused data indicate weobtain promising results. The method is scalable and can also be applied to other smartnetwork of sensors. We provide an application in distributed coupled video-inertial sensorbased 3D reconstruction for human movement analysis in real time. Full article
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Open AccessArticle
Performance Comparison of a Novel Adaptive Protocol with the Fixed Power Transmission in Wireless Sensor Networks
J. Sens. Actuator Netw. 2015, 4(4), 274-292; doi:10.3390/jsan4040274 -
Abstract
In this paper, we compare the performance of a novel adaptive protocol with the fixed power transmission protocol using experimental data when the distance between the transmitter and the receiver is fixed. In fixed power transmission protocol, corresponding to the distance between [...] Read more.
In this paper, we compare the performance of a novel adaptive protocol with the fixed power transmission protocol using experimental data when the distance between the transmitter and the receiver is fixed. In fixed power transmission protocol, corresponding to the distance between the sensor and the hub, there is a fixed power level that provides the optimal or minimum value in terms of energy consumption while maintaining a threshold Quality of Service (QoS) parameter. This value is bounded by the available output power levels of a given radio transceiver. The proposed novel adaptive power control protocol tracks and supersedes that energy expenditure by using an intelligent algorithm to ramp up or down the output power level as and when required. This protocol does not use channel side information in terms of received signal strength indication (RSSI) or link quality indication (LQI) for channel estimation to decide the transmission power. It also controls the number of allowed retransmissions for error correction. Experimental data have been collected at different distances between the transmitting sensor and the hub. It can be observed that the energy consumption of the fixed power level is at least 25% more than the proposed adaptive protocol for comparable packet success rate. Full article