Search results for "paikannus"
showing 10 items of 26 documents
Analysis and Evaluation of Adaptive RSSI-based Ranging in Outdoor Wireless Sensor Networks
2019
Estimating inter-node distances based on received radio signal strength (RSSI) is the foundation of RSSI-based outdoor localization in wireless sensor networks (WSNs). However, the accuracy of RSSI-based ranging depends on environmental and weather conditions. Therefore, it is important that RSSI-based ranging adapts to prevailing conditions to improve its range and location accuracy. This paper analyzes and evaluates RSSI-based ranging and adaptive techniques in outdoor WSNs to improve the range quality. The findings highlight the effects of path loss exponent (PLE) estimation error and temperature change on RSSI-based ranging. Consequently, we analyze techniques for mitigating these detri…
Scavenging in the realm of senses: smell and vision drive recruitment at carcasses in Neotropical ecosystems
2022
Social information, acquired through the observation of other individuals, is especially relevant among species belonging to the same guild. The unpredictable and ephemeral nature of carrion implies that social mechanisms may be selected among scavenger species to facilitate carcass location and consumption. Here, we apply a survival-modelling strategy to data obtained through the placement and monitoring of carcasses in the field to analyse possible information transmission cascades within a Neotropical scavenger community. Our study highlights how the use of different senses (smell and sight) within this guild facilitates carcass location through the transmission of social information bet…
EGNOS augmented satellite positioning
2007
Improving RF Fingerprinting Methods by Means of D2D Communication Protocol
2019
Radio Frequency (RF) fingerprinting is widely applied for indoor positioning due to the existing Wi-Fi infrastructure present in most indoor spaces (home, work, leisure, among others) and the widespread usage of smartphones everywhere. It corresponds to a simple idea, the signal signature in a location tends to be stable over the time. Therefore, with the signals received from multiple APs, a unique fingerprint can be created. However, the Wi-Fi signal is affected by many factors which degrade the positioning error range to around a few meters. This paper introduces a collaborative method based on device-to-device (D2D) communication to improve the positioning accuracy using only fingerprin…
RF fingerprinting for user locationing in LTE/WLAN networks
2016
Location based applications and services have become popular in many wireless communication devices. This thesis study presents a performance evaluation of Radio Frequency (RF) fingerprinting framework in heterogeneous Long Term Evolution (LTE) and Wireless Local Area Networks (WLAN) using Minimization of Drive Testing (MDT) measurements which allow automated construction of extensive RF fingerprint training databases. Utilization of MDT data could create additional opportunities for service provider and application developers. Typical RF fingerprint consist of radio measurements from multiple LTE transceiver stations and WLAN access points. Regardless environmental conditions, received sig…
Klusterointi radiotaajuuspaikannuksessa
2017
Mobiililaitteiden tarkalla paikantamisella on tärkeä rooli nykyisissä ja tulevissa langattomiin verkkoihin perustuvissa sovelluksissa. GPS-paikannus on yleisesti käytetty, mutta se suoriutuu kehnosti sisätiloissa ja saattaa ruuhkahuippujen aikana olla kykenemätön suorittamaan kaikkia paikannuspyyntöjä tehokkaasti. Mobiiliverkossa paikannus voidaan suorittaa kolmiomittauksen avulla, joka vaatii kuitenkin aktiivisen puhelun. Paikkatieto mahdollistaa verkko-operaattoreille ajantasaisen statistiikan keräämisen muuttuvassa radioverkkoympäristössä. Se auttaa myös parantamaan tilannetietoisuutta onnettomuuksien ja pelastusoperaatioiden aikana. Langattomien verkkojen massiivista dataa ei vielä ole …
MOBIlity assessment with modern TEChnology in older patients’ real-life by the General Practitioner: the MOBITEC-GP study protocol
2019
Abstract Background Mobility limitations in older adults are associated with poor clinical outcomes including higher mortality and disability rates. A decline in mobility (including physical function and life-space) is detectable and should be discovered as early as possible, as it can still be stabilized or even reversed in early stages by targeted interventions. General practitioners (GPs) would be in the ideal position to monitor the mobility of their older patients. However, easy-to-use and valid instruments for GPs to conduct mobility assessment in the real-life practice setting are missing. Modern technologies such as the global positioning system (GPS) and inertial measurement units …
Sensors / Cross-country skiing analysis and ski technique detection by high-precision kinematic global navigation satellite system
2019
Cross-country skiing (XCS) embraces a broad variety of techniques applied like a gear system according to external conditions, slope topography, and skier-related factors. The continuous detection of applied skiing techniques and cycle characteristics by application of unobtrusive sensor technology can provide useful information to enhance the quality of training and competition. (1) Background: We evaluated the possibility of using a high-precision kinematic global navigation satellite system (GNSS) to detect cross-country skiing classical style technique. (2) Methods: A world-class male XC skier was analyzed during a classical style 5.3-km time trial recorded with a high-precision kinemat…
Continuous Analysis of Running Mechanics by Means of an Integrated INS/GPS Device
2019
This paper describes a single body-mounted sensor that integrates accelerometers, gyroscopes, compasses, barometers, a GPS receiver, and a methodology to process the data for biomechanical studies. The sensor and its data processing system can accurately compute the speed, acceleration, angular velocity, and angular orientation at an output rate of 400 Hz and has the ability to collect large volumes of ecologically-valid data. The system also segments steps and computes metrics for each step. We analyzed the sensitivity of these metrics to changing the start time of the gait cycle. Along with traditional metrics, such as cadence, speed, step length, and vertical oscillation, this system est…
Katsaus virtuaalitodellisuuden syöttölaitteiden toteutusteknologioihin
2016
Virtuaalitodellisuuden syöttölaitteista on olemassa julkista tutkimusta varsin niukasti, vaikka ne ovat virtuaalitodellisuudelle korvaamattoman tärkeitä. Syöttölaitteiden tärkeintehtäväontuottaakäyttäjälleluonnollinenkäyttöliittymävirtuaalitodellisuuteen.Käyt- töliittymän luonnollisuus mahdollistaa käyttäjän immersoitumisen eli täydellisen uppoutu- misen virtuaalikokemukseen. Esittelen tässä tutkielmassa yleisimpiä nykyaikaisissa virtuaa- litodellisuuden syöttölaitteissa käytettyjä paikannusteknologoita ja pohdin niiden vaikutusta immersioon. Although, virtual reality input devices are irreplaceable for virtual reality, there is little public research on the subject. The most important func…