855 research outputs found
Sensing motion using spectral and spatial analysis of WLAN RSSI
In this paper we present how motion sensing can be obtained just by observing the WLAN radio signal strength and its fluctuations. The temporal, spectral and spatial characteristics of WLAN signal are analyzed. Our analysis
confirms our claim that ’signal strength from access points appear to jump around more vigorously when the device is moving compared to when it is still and the number of detectable access points vary considerably while the user is on the move’. Using this observation, we present a novel motion detection algorithm, Spectrally Spread Motion Detection (SpecSMD) based on the spectral analysis of
WLAN signal’s RSSI. To benchmark the proposed algorithm, we used Spatially Spread Motion Detection (SpatSMD), which is inspired by the recent work of Sohn et al. Both algorithms were evaluated by carrying out extensive measurements
in a diverse set of conditions (indoors in different buildings and outdoors - city center, parking lot, university campus etc.,) and tested against the same
data sets. The 94% average classification accuracy of the proposed SpecSMD is outperforming the accuracy of SpatSMD (accuracy 87%). The motion detection algorithms presented in this paper provide ubiquitous methods for deriving the
state of the user. The algorithms can be implemented and run on a commodity device with WLAN capability without the need of any additional hardware support
Testbed architecture and framework for debugging wireless sensor networks
The Internet of Things has emerged as one of the key aspects for the future of the Wireless Sensor Networks and their impact on new applications in real environments. This concept poses new challenges in the implementation, testing and debugging of efficient, robust and reliable technologies under this paradigm, specially in a pre-deployment stage where HW-SW platform prototypes are to be optimized prior to their inclusion in actual deployments. In this work, the design and implementation of a complete testbed infrastructure as a support tool for improving the effectiveness and the applicability of sensor nodes to real systems is presented, focused on the modular architecture of the Cookie platform and aiming to help developers to integrate and improve the whole WSN operation to final real-world scenarios
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Context-awareness for mobile sensing: a survey and future directions
The evolution of smartphones together with increasing computational power have empowered developers to create innovative context-aware applications for recognizing user related social and cognitive activities in any situation and at any location. The existence and awareness of the context provides the capability of being conscious of physical environments or situations around mobile device users. This allows network services to respond proactively and intelligently based on such awareness. The key idea behind context-aware applications is to encourage users to collect, analyze and share local sensory knowledge in the purpose for a large scale community use by creating a smart network. The desired network is capable of making autonomous logical decisions to actuate environmental objects, and also assist individuals. However, many open challenges remain, which are mostly arisen due to the middleware services provided in mobile devices have limited resources in terms of power, memory and bandwidth. Thus, it becomes critically important to study how the drawbacks can be elaborated and resolved, and at the same time better understand the opportunities for the research community to contribute to the context-awareness. To this end, this paper surveys the literature over the period of 1991-2014 from the emerging concepts to applications of context-awareness in mobile platforms by providing up-to-date research and future research directions. Moreover, it points out the challenges faced in this regard and enlighten them by proposing possible solutions
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Location-based Data Analysis of Visitor Structure for Recreational Area Management
This work presents a location-based data analysis framework for profiling visitors structures. In terms of recreational area management, understanding visitors’ structure and popularity is important. Traditionally, visitors monitoring with automatic counting devices has drawbacks of inaccurate visitors counting. In this work, compared to automatic counting devices, we use Wi-Fi tracking as the main method to count visitors, which provides a fairly precise picture of visitor structures. Moreover, we deliver rich analytic functions in this framework and we present the functionality with visitor data collected from Guanyinshan Visitor Center. This framework not only standardizes visitor counting process but also facilitates a profound analysis of visitor structures.
Key Words:
Guanyinshan Visitor Center, Wi-Fi trackin
A Safe, Efficient and Integrated Indoor Robotic Fleet for Logistic Applications in Healthcare and Commercial Spaces: The ENDORSE Concept
International audienceHospitals are rightfully considered a field of indoor logistic robotics of high commercial potential. However, today, only a handful of mobile robotic solutions for hospital logistics exist that have failed to trigger widespread acceptance by the market. This is because existing systems require costly infrastructure installation, they do not easily integrate to corporate IT solutions, are not adequately shielded from cybersecurity threats, and as a result, they do not fully automate procedures and traceability of the items they carry. Moreover, existing systems are limited on scope, focusing only on delivery services, and hence do not provide any other type of support to the medical and nursing staff. ENDORSE system will address the aforementioned technical challenges and functional limitations by pursuing four innovation pillars: (i) infrastructure-less multi-robot indoor navigation; (ii) advanced Human-Robot Interaction (HRI) for resolving deadlocks and achieving efficient sharing of space resources in crowded environments; (iii) deployment of the ENDORSE software as a cloud-based service facilitating its integration with corporate software solutions, complying with GDPR data security requirements; (iv) reconfigurable and modular hardware architectures so that diverse modules can be easily swapped. ENDORSE functionality will be demonstrated via the integration of an e-diagnostic support module for vital signs monitoring on a fleet of mobile robots, facilitating connectivity to cloud-based Electronic Health Records (EHR), and validated in an operational hospital environment for realistic assessment
Testbed infrastructure for debugging, analyzing and optimizing WSN nodes based on a modular HW-SW architecture
The Internet of Things has emerged as one of the key
aspects to the future of the Wireless Sensor Networ
ks and their impact in new applications in real environments. This concept poses new challenges in the implementation, testing and assessment of efficient, robust and reliable technologies and prototypes under this paradigm. In this way, the run-time remote interaction with the deployment of hundreds of in-f
ield nodes in which developers have to be able to control and manage the wireless network anywhere at any time also implies new objectives to be achieved in order to adapt or even create new HW-SW platforms. In this work, the design and implementation of a complete testbed infrastructure as a support tool for improving the effectiveness and the applicability of sensor nodes
to real applications is presented, focused on the m
odular architecture of the Cookie hardware platform and aiming to help developers to integrate and optimize the whole WSN system to the final applications in the real world
iBILL: Using iBeacon and Inertial Sensors for Accurate Indoor Localization in Large Open Areas
As a key technology that is widely adopted in location-based services (LBS), indoor localization has received considerable attention in both research and industrial areas. Despite the huge efforts made for localization using smartphone inertial sensors, its performance is still unsatisfactory in large open areas, such as halls, supermarkets, and museums, due to accumulated errors arising from the uncertainty of users’ mobility and fluctuations of magnetic field. Regarding that, this paper presents iBILL, an indoor localization approach that jointly uses iBeacon and inertial sensors in large open areas. With users’ real-time locations estimated by inertial sensors through an improved particle filter, we revise the algorithm of augmented particle filter to cope with fluctuations of magnetic field. When users enter vicinity of iBeacon devices clusters, their locations are accurately determined based on received signal strength of iBeacon devices, and accumulated errors can, therefore, be corrected. Proposed by Apple Inc. for developing LBS market, iBeacon is a type of Bluetooth low energy, and we characterize both the advantages and limitations of localization when it is utilized. Moreover, with the help of iBeacon devices, we also provide solutions of two localization problems that have long remained tough due to the increasingly large computational overhead and arbitrarily placed smartphones. Through extensive experiments in the library on our campus, we demonstrate that iBILL exhibits 90% errors within 3.5 m in large open areas
Sensor Network Based Collision-Free Navigation and Map Building for Mobile Robots
Safe robot navigation is a fundamental research field for autonomous robots
including ground mobile robots and flying robots. The primary objective of a
safe robot navigation algorithm is to guide an autonomous robot from its
initial position to a target or along a desired path with obstacle avoidance.
With the development of information technology and sensor technology, the
implementations combining robotics with sensor network are focused on in the
recent researches. One of the relevant implementations is the sensor network
based robot navigation. Moreover, another important navigation problem of
robotics is safe area search and map building. In this report, a global
collision-free path planning algorithm for ground mobile robots in dynamic
environments is presented firstly. Considering the advantages of sensor
network, the presented path planning algorithm is developed to a sensor network
based navigation algorithm for ground mobile robots. The 2D range finder sensor
network is used in the presented method to detect static and dynamic obstacles.
The sensor network can guide each ground mobile robot in the detected safe area
to the target. Furthermore, the presented navigation algorithm is extended into
3D environments. With the measurements of the sensor network, any flying robot
in the workspace is navigated by the presented algorithm from the initial
position to the target. Moreover, in this report, another navigation problem,
safe area search and map building for ground mobile robot, is studied and two
algorithms are presented. In the first presented method, we consider a ground
mobile robot equipped with a 2D range finder sensor searching a bounded 2D area
without any collision and building a complete 2D map of the area. Furthermore,
the first presented map building algorithm is extended to another algorithm for
3D map building
OSEM : occupant-specific energy monitoring.
Electricity has become prevalent in modern day lives. Almost all the comforts people enjoy today, like home heating and cooling, indoor and outdoor lighting, computers, home and office appliances, depend on electricity. Moreover, the demand for electricity is increasing across the globe. The increasing demand for electricity and the increased awareness about carbon footprints have raised interest in the implementation of energy efficiency measures. A feasible remedy to conserve energy is to provide energy consumption feedback. This approach has suggested the possibility of considerable reduction in the energy consumption, which is in the range of 3.8% to 12%. Currently, research is on-going to monitor energy consumption of individual appliances. However, various approaches studied so far are limited to group-level feedback. The limitation of this approach is that the occupant of a house/building is unaware of his/her energy consumption pattern and has no information regarding how his/her energy-related behavior is affecting the overall energy consumption of a house/building. Energy consumption of a house/building largely depends on the energy-related behavior of individual occupants. Therefore, research in the area of individualized energy-usage feedback is essential. The OSEM (Occupant-Specific Energy Monitoring) system presented in this work is capable of monitoring individualized energy usage. OSEM system uses the electromagnetic field (EMF) radiated by appliances as a signature for appliance identification. An EMF sensor was designed and fabricated to collect the EMF radiated by appliances. OSEM uses proximity sensing to confirm the energy-related activity. Once confirmed, this activity is attributed to the occupant who initiated it. Bluetooth Low Energy technology was used for proximity sensing. This OSEM system would provide a detailed energy consumption report of individual occupants, which would help the occupants understand their energy consumption patterns and in turn encourage them to undertake energy conservation measures
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