52 research outputs found

    Applying Augmented Reality to Outdoors Industrial Use

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    Augmented Reality (AR) is currently gaining popularity in multiple different fields. However, the technology for AR still requires development in both hardware and software when considering industrial use. In order to create immersive AR applications, more accurate pose estimation techniques to define virtual camera location are required. The algorithms for pose estimation often require a lot of processing power, which makes robust pose estimation a difficult task when using mobile devices or designated AR tools. The difficulties are even larger in outdoor scenarios where the environment can vary a lot and is often unprepared for AR. This thesis aims to research different possibilities for creating AR applications for outdoor environments. Both hardware and software solutions are considered, but the focus is more on software. The majority of the thesis focuses on different visual pose estimation and tracking techniques for natural features. During the thesis, multiple different solutions were tested for outdoor AR. One commercial AR SDK was tested, and three different custom software solutions were developed for an Android tablet. The custom software solutions were an algorithm for combining data from magnetometer and a gyroscope, a natural feature tracker and a tracker based on panorama images. The tracker based on panorama images was implemented based on an existing scientific publication, and the presented tracker was further developed by integrating it to Unity 3D and adding a possibility for augmenting content. This thesis concludes that AR is very close to becoming a usable tool for professional use. The commercial solutions currently available are not yet ready for creating tools for professional use, but especially for different visualization tasks some custom solutions are capable of achieving a required robustness. The panorama tracker implemented in this thesis seems like a promising tool for robust pose estimation in unprepared outdoor environments.Lisätyn todellisuuden suosio on tällä hetkellä kasvamassa usealla eri alalla. Saatavilla olevat ohjelmistot sekä laitteet eivät vielä riitä lisätyn todellisuuden soveltamiseen ammattimaisessa käytössä. Erityisesti posen estimointi vaatii tarkempia menetelmiä, jotta immersiivisten lisätyn todellisuuden sovellusten kehittäminen olisi mahdollista. Posen estimointiin (laitteen asennon- sekä paikan arviointiin) käytetyt algoritmit ovat usein monimutkaisia, joten ne vaativat merkittävästi laskentatehoa. Laskentatehon vaatimukset ovat usein haasteellisia varsinkin mobiililaitteita sekä lisätyn todellisuuden laitteita käytettäessä. Lisäongelmia tuottaa myös ulkotilat, jossa ympäristö voi muuttua usein ja ympäristöä ei ole valmisteltu lisätyn todellisuuden sovelluksille. Diplomityön tarkoituksena on tutkia mahdollisuuksia lisätyn todellisuuden sovellusten kehittämiseen ulkotiloihin. Sekä laitteisto- että ohjelmistopohjaisia ratkaisuja käsitellään. Ohjelmistopohjaisia ratkaisuja käsitellään työssä laitteistopohjaisia ratkaisuja laajemmin. Suurin osa diplomityöstä keskittyy erilaisiin visuaalisiin posen estimointi tekniikoihin, jotka perustuvat kuvasta tunnistettujen luonnollisten piirteiden seurantaan. Työn aikana testattiin useita ratkaisuja ulkotiloihin soveltuvaan lisättyyn todellisuuteen. Yhtä kaupallista työkalua testattiin, jonka lisäksi toteutettiin kolme omaa sovellusta Android tableteille. Työn aikana kehitetyt sovellukset olivat yksinkertainen algoritmi gyroskoopin ja magnetometrin datan yhdistämiseen, luonnollisen piirteiden seuranta-algoritmi sekä panoraamakuvaan perustuva seuranta-algoritmi. Panoraamakuvaan perustuva seuranta-algoritmi on toteuteutettu toisen tieteellisen julkaisun pohjalta, ja algoritmia jatkokehitettiin integroimalla se Unity 3D:hen. Unity 3D-integrointi mahdollisti myös sisällön esittämisen lisätyn todellisuuden avulla. Työn lopputuloksena todetaan, että lisätyn todellisuuden teknologia on lähellä pistettä, jossa lisätyn todellisuuden työkaluja voitaisiin käyttää ammattimaisessa käytössä. Tällä hetkellä saatavilla olevat kaupalliset työkalut eivät vielä pääse ammattikäytön vaatimalle tasolle, mutta erityisesti visualisointitehtäviin soveltuvia ei-kaupallisia ratkaisuja on jo olemassa. Lisäksi työn aikana toteutetun panoraamakuviin perustuvan seuranta-algoritmin todetaan olevan lupaava työkalu posen estimointiin ulkotiloissa.Siirretty Doriast

    Evaluation of the GPS Accuracy of Tablets

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    Augmented Reality (AR) applications often require knowledge of the user’s position in some global coordinate system in order to draw the augmented content to its correct position on the screen. The most common method for coarse positioning is the Global Positioning System (GPS). One of the advantages of GPS is that GPS receivers can be found in almost every modern mobile device. This research was conducted in order to determine the accuracies of different GPS receivers. The tests included seven consumer-grade tablets, three external GPS modules and one professional-grade GPS receiver. All of the devices were tested with both static and mobile measurements. It was concluded that even the cheaper external GPS receivers were notably more accurate than the GPS receivers of the tested tablets. The absolute accuracy of the tablets is difficult to determine from the test results, since the results vary by a large margin between different measurements. The accuracy of the tested tablets in static measurements were between 0.30 meters and 13.75 meters.Siirretty Doriast

    Finnish agriculture and rural industries 2007

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    The report consists of following topics: operating environment of agriculture, agricultural and food market, agricultural policy, economic situation of agriculture, agriculture and the environment, rural and regional policy, special topics: biogas etc

    The past and the present in decision-making: the use of conspecific and heterospecific cues in nest site selection

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    Nest-site selection significantly affects fitness, so adaptations for assessment of the qualities of available sites are expected. The assessment may be based on personal or social information, social information referring to the observed location and performance of both con- and heterospecific individuals. Contrary to large-scale breeding habitat selection, small-scale nest-site selection within habitat patches is insufficiently understood. We analyzed nest-site selection in the migratory collared flycatcher Ficedula albicollis in relation to present and past cues provided by conspecifics and by resident tits within habitat patches by using long-term data. Collared flycatchers preferred nest boxes that were occupied by conspecifics in the previous year. This preference was strongest in breeding pairs where both individuals bred in the same forest patch in the previous year. The results also suggest preference for nest boxes close to boxes where conspecifics had a high breeding success in the previous year, and for nest boxes which are presently surrounded by a high number of breeding great tits Parus major. The results indicate social information use in nest-site selection at a small spatial scale, where collared flycatchers use conspecific cues with a time lag of one year and heterospecific cues instantly.</p

    Titmice are a better indicator of bird density in Northern European than in Western European forests

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    Publisher Copyright: © 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.Population sizes of many birds are declining alarmingly and methods for estimating fluctuations in species’ abundances at a large spatial scale are needed. The possibility to derive indicators from the tendency of specific species to co-occur with others has been overlooked. Here, we tested whether the abundance of resident titmice can act as a general ecological indicator of forest bird density in European forests. Titmice species are easily identifiable and have a wide distribution, which makes them potentially useful ecological indicators. Migratory birds often use information on the density of resident birds, such as titmice, as a cue for habitat selection. Thus, the density of residents may potentially affect community dynamics. We examined spatio-temporal variation in titmouse abundance and total bird abundance, each measured as biomass, by using long-term citizen science data on breeding forest birds in Finland and France. We analyzed the variation in observed forest bird density (excluding titmice) in relation to titmouse abundance. In Finland, forest bird density linearly increased with titmouse abundance. In France, forest bird density nonlinearly increased with titmouse abundance, the association weakening toward high titmouse abundance. We then analyzed whether the abundance (measured as biomass) of random species sets could predict forest bird density better than titmouse abundance. Random species sets outperformed titmice as an indicator of forest bird density only in 4.4% and 24.2% of the random draws, in Finland and France, respectively. Overall, the results suggest that titmice could act as an indicator of bird density in Northern European forest bird communities, encouraging the use of titmice observations by even less-experienced observers in citizen science monitoring of general forest bird density.Peer reviewe

    Interspecific information on predation risk affects nest site choice in a passerine bird

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    BackgroundBreeding site choice constitutes an important part of the species niche. Nest predation affects breeding site choice, and has been suggested to drive niche segregation and local coexistence of species. Interspecific social information use may, in turn, result in copying or rejection of heterospecific niche characteristics and thus affect realized niche overlap between species. We tested experimentally whether a migratory bird, the pied flycatcher Ficedula hypoleuca, collects information about nest predation risk from indirect cues of predators visiting nests of heterospecific birds. Furthermore, we investigated whether the migratory birds can associate such information with a specific nest site characteristic and generalize the information to their own nest site choice.ResultsOur results demonstrate that flycatchers can use the fate of heterospecific nesting attempts in their own nest site choice, but do so selectively. Young flycatcher females, when making the decision quickly, associated the fate of an artificial nest with nest-site characteristics and avoided the characteristic associated with higher nest predation risk.ConclusionsCopying nest site choices of successful heterospecifics, and avoiding choices which led to failed attempts, may amplify or counter effects of nest predation on niche overlap, with important consequences for between-species niche divergence-convergence dynamics, species coexistence and predator-prey interactions.</div

    Do large-scale associations in birds imply biotic interactions or environmental filtering?

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    Aim There has been a wide interest in the effect of biotic interactions on species' occurrences and abundances at large spatial scales, coupled with a vast development of the statistical methods to study them. Still, evidence for whether the effects of within-trophic-level biotic interactions (e.g. competition and heterospecific attraction) are discernible beyond local scales remains inconsistent. Here, we present a novel hypothesis-testing framework based on joint dynamic species distribution models and functional trait similarity to dissect between environmental filtering and biotic interactions. Location France and Finland. Taxon Birds. Methods We estimated species-to-species associations within a trophic level, independent of the main environmental variables (mean temperature and total precipitation) for common species at large spatial scale with joint dynamic species distribution (a multivariate spatiotemporal delta model) models. We created hypotheses based on species' functionality (morphological and/or diet dissimilarity) and habitat preferences about the sign and strength of the pairwise spatiotemporal associations to estimate the extent to which they result from biotic interactions (competition, heterospecific attraction) and/or environmental filtering. Results Spatiotemporal associations were mostly positive (80%), followed by random (15%), and only 5% were negative. Where detected, negative spatiotemporal associations in different communities were due to a few species. The relationship between spatiotemporal association and functional dissimilarity among species was negative, which fulfils the predictions of both environmental filtering and heterospecific attraction. Main conclusions We showed that processes leading to species aggregation (mixture between environmental filtering and heterospecific attraction) seem to dominate assembly rules, and we did not find evidence for competition. Altogether, our hypothesis-testing framework based on joint dynamic species distribution models and functional trait similarity is beneficial in ecological interpretation of species-to-species associations from data covering several decades and biogeographical regions.Peer reviewe

    Interspecific information on predation risk affects nest site choice in a passerine bird

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    Abstract Background Breeding site choice constitutes an important part of the species niche. Nest predation affects breeding site choice, and has been suggested to drive niche segregation and local coexistence of species. Interspecific social information use may, in turn, result in copying or rejection of heterospecific niche characteristics and thus affect realized niche overlap between species. We tested experimentally whether a migratory bird, the pied flycatcher Ficedula hypoleuca, collects information about nest predation risk from indirect cues of predators visiting nests of heterospecific birds. Furthermore, we investigated whether the migratory birds can associate such information with a specific nest site characteristic and generalize the information to their own nest site choice. Results Our results demonstrate that flycatchers can use the fate of heterospecific nesting attempts in their own nest site choice, but do so selectively. Young flycatcher females, when making the decision quickly, associated the fate of an artificial nest with nest-site characteristics and avoided the characteristic associated with higher nest predation risk. Conclusions Copying nest site choices of successful heterospecifics, and avoiding choices which led to failed attempts, may amplify or counter effects of nest predation on niche overlap, with important consequences for between-species niche divergence-convergence dynamics, species coexistence and predator-prey interactions

    Virtual and Augmented Reality Solutions to Industrial Applications

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    This paper introduces a variety of virtual and augmented reality solutions for industrial applications. In addition the technologies and techniques required for producing these kind of solutions are presented. The issues studied in research projects referred here include data connectivity, processing and 3D visualization of construction models, positioning and tracking solutions and user experience design. An open database containing evaluations about available virtual and augmented reality platforms is also presented.</p

    Amidst the flyway: co-designing accommodation fields for the barnacle goose in south-eastern Finland

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    The barnacle goose (Branta leucopsis) is strictly protected under the Finnish national and EU legislation. The protection has succeeded: the size of the Russia/Germany and Netherlands population has increased from 20 000 individuals to 1.4 million individuals in 40 years (1980-2020). Some 500 000-800 000 individuals of this population nowadays stopover in Finland during their spring and autumn migrations between their breeding grounds in the Russian Arctic and wintering grounds along the North Sea coast. To the frustration of the farmers, resting and feeding in the agricultural areas cause major damage, resulting in a human-wildlife conflict - the alleviation of which calls for a wide range of approaches. The reimbursement for farmers has dramatically increased in ten years, with €3 million paid by the Finnish government in 2020. In collaboration with local farmers and regional and national environmental administration, we co-designed and experimentally tested accommodation fields for geese using a rights-based framework. On these fields, geese are allowed to forage and rest without disturbance, while geese are repelled from neighbouring fields, dedicated to regular farming. In this chapter, we explain our transdisciplinary findings about the institutional and natural conditions of these accommodation fields.Peer reviewe
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