366 research outputs found

    Wireless mobile ad-hoc sensor networks for very large scale cattle monitoring

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    This paper investigates the use of wireless mobile ad hoc sensor networks in the nationwide cattle monitoring systems. This problem is essential for monitoring general animal health and detecting outbreaks of animal diseases that can be a serious threat for the national cattle industry and human health. We begin by describing a number of related approaches for supporting animal monitoring applications and identify a comprehensive set of requirements that guides our approach. We then propose a novel infrastructure-less, self -organized peer to peer architecture that fulfills these requirements. The core of our work is the novel data storage and routing protocol for large scale, highly mobile ad hoc sensor networks that is based on the Distributed Hash Table (DHT) substrate that we optimize for disconnections. We show over a range of extensive simulations that by exploiting nodes’ mobility, packet overhearing and proactive caching we significantly improve availability of sensor data in these extreme conditions

    Wireless mobile ad-hoc sensor networks for very large scale cattle monitoring

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    This paper investigates the use of wireless mobile ad hoc sensor networks in the nationwide cattle monitoring systems. This problem is essential for monitoring general animal health and detecting outbreaks of animal diseases that can be a serious threat for the national cattle industry and human health. We begin by describing a number of related approaches for supporting animal monitoring applications and identify a comprehensive set of requirements that guides our approach. We then propose a novel infrastructure-less, self -organized peer to peer architecture that fulfills these requirements. The core of our work is the novel data storage and routing protocol for large scale, highly mobile ad hoc sensor networks that is based on the Distributed Hash Table (DHT) substrate that we optimize for disconnections. We show over a range of extensive simulations that by exploiting nodes’ mobility, packet overhearing and proactive caching we significantly improve availability of sensor data in these extreme conditions

    Enabling rapid and cost-effective creation of massive pervasive games in very unstable environments

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    Pervasive gaming is a new form of multimedia entertainment that extends the traditional computer gaming experience out into the real world. Through a combination of personal devices, positioning systems and other sensors, combined with wireless networking, a pervasive game can respond to player's movements and context and enable them to communicate with a game engine and other players. We review our recent deployment examples of pervasive games in order to explain their distinctive characteristics as wireless ad-hoc networking applications. We then identify the network support challenges of scaling pervasive games to include potentially mass numbers of players across extremely heterogeneous and unreliable networks. We propose a P2P overlay capable of storing large amount of game related data, which is the key to combating the loss of coverage and potential dishonesty of players. The proposed protocol decreases the deployment costs of the gaming infrastructure by self organization and utilizing storage space of users' devices. We demonstrate scalability and increased availability of data offered by the proposed protocol in simulation based evaluatio

    Phytosociology of snowbed and exposed ridge vegetation of Svalbard

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    Arctic vegetation still lacks a uniform system to classify its plant communities, the current arrangement of the phytosociological data being difficult to interpret. However, using modern methods, it has proved possible to organize the current data to create a suitable system based on numerical algorithms (detrended correspondence analysis and cluster analysis) and traditional methods for 135 phytosociological relevés from snowbed and exposed ridge habitats of Svalbard; 125 relevés were selected from twentieth and early twenty-first century publications, and ten relevés were collected by our group in 2012 from the Kaffiøyra Plain (Oscar II Land, NW Spitsbergen). Our analysis has shown there to be four associations and one community. Two associations and one community are distinguished within the Luzulion arcticae Gjærev. 1950: (1) the Pedicularietum hirsutae ass. nov., (2) the Deschampsietum alpinae (Nordh. 1943) Węgrzyn and Wietrzyk 2015 stat. nov., and (3) the Minuartia biflora community. Two syntaxa were assigned to the Luzulion arcuatae Elvebakk ex Węgrzyn and Wietrzyk 2015: (4) the Anthelietum juratzkanae Kobayashi ex Węgrzyn and Wietrzyk 2015 with a confirmed status and (5) the Gymnomitrietum coralloidis Hadač ex Węgrzyn and Wietrzyk 2015 stat. nov. was described by means of a new approach

    Increasing communication reliability in manufacturing environments

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    This paper is concerned with low cost mechanisms that can increase reliability of machine to machine and machine to cloud communications in increasingly complex manufacturing environments that are prone to disconnections and faults. We propose a novel distributed and cooperative sensing framework that supports localized real time predictive analytics of connectivity patterns and detection of a range of faults together with issuing of notifications and responding on demand queries. We show that our Fault and Disconnection Aware Smart Sensing (FDASS) framework achieves significantly lower packet loss rates and communication delays in the face of unreliable nodes and networks when compared to the state of the art and benchmark approaches

    From barren substrate to mature tundra : lichen colonization in the forelands of Svalbard glaciers

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    This paper contributes to studies on the lichen biota of Arctic regions. The research was carried out in the forelands of eight glaciers and in the mature tundra surrounding them. Study areas were located in two parts of Svalbard: in the Kongsfjord (forelands of Austre Brøggerbreen, Vestre Brøggerbreen, Austre Lovénbreen, Midtre Lovénbreen, and Vestre Lovénbreen) and in the Isfjord (forelands of Rieperbreen, Svenbreen, and Ferdinandbreen). In each foreland and in the mature tundra surrounding it, a series of 1-m2 plots was established, within which a percentage cover for each species was determined. In total, 133 lichens and one lichenicolous fungus were recorded. Nineteen species were recorded for the first time in Svalbard: Agonimia allobata, Atla wheldonii, Bacidia herbarum, Catolechia wahlenbergii, Epigloea soleiformis, Lecanora behringii, Lepraria subalbicans, Leptogium arcticum, Pertusaria pseudocorallina, Placidiopsis custnani, Protothelenella corrosa, Pyrenidium actinellum, Spilonema revertens, Stereocaulon saxatile, Thelocarpon sphaerosporum, Toninia coelestina, Verrucaria elaeina, Verrucaria murina, and Verrucaria xyloxena. The lichen richness was the lowest in the Ferdinandbreen foreland (24 species) and the highest in the Rieperbreen foreland (82 species). Significant differences in species composition were found among the forelands studied, except for Austre and Vestre Brøggerbreen whose lichen composition was similar. The differences in lichen composition between mature tundra in the vicinity of the following forelands were identified: Vestre Brøggerbreen and Svenbreen, Austre Brøggerbreen and Svenbreen, and Austre Brøggerbreen and Ferdinandbreen. The most dominant group of lichens in both forelands and mature tundra were chlorolichens, not cyanolichens

    Tardigrada in Svalbard lichens : diversity, densities and habitat heterogeneity

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    Tardigrades in lichens have been poorly studied with few papers published on their ecology and diversity so far. The aims of our study are to determine the (1) influence of habitat heterogeneity on the densities and species diversity of tardigrade communities in lichens as well as the (2) effect of nutrient enrichment by seabirds on tardigrade densities in lichens. Forty-five lichen samples were collected from Spitsbergen, Nordaustlandet, Prins Karls Forland, Danskøya, Fuglesongen, Phippsøya and Parrøya in the Svalbard archipelago. In 26 samples, 23 taxa of Tardigrada (17 identified to species level) were found. Twelve samples consisted of more than one lichen species per sample (with up to five species). Tardigrade densities and taxa diversity were not correlated with the number of lichen species in a single sample. Moreover, the densities of tardigrades was not significantly higher in lichens collected from areas enriched with nutrients by seabirds in comparison to those not enriched. The incorporation of previously published data on the tardigrades of Spitsbergen into the analysis showed that tardigrade densities was significantly higher in moss than it was in lichen samples. We propose that one of the most important factors influencing tardigrade densities is the cortex layer, which is a barrier for food sources, such as live photosynthetic algal cells in lichens. Finally, the new records of Tardigrada and the first and new records of lichens in Svalbard archipelago are presented

    Organic carbon accumulation in the glacier forelands with regard to variability of environmental conditions in different ecogenesis stages of High Arctic ecosystems

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    Recently deglaciated surfaces of glacier forelands are subjected to a variety of biotic and abiotic factors that lead to continuous soil formation. Until now, no attempt has been taken to analyse multiple factors that might affect soil development in the Arctic forelands. The main aim of this research was to determine the factors that influence soil development in the eight forelands of Svalbard. Moreover, the effects of both habitat type (glacier foreland and mature tundra) and geographical location on environmental variables treated as potential factors influencing soil formation were tested. In 2017, at each location a series of 1 m2m^{2} plots was established; all 168 plots were investigated in terms of soil properties, spatial data, biological soil crusts (BSCs) properties, percent cover of BSCs and vascular plants. Stepwise multiple linear regression analysis using forward variable selection showed that soil development was significantly associated with six of fifteen analysed factors, i.e. BSC cover, carbon and nitrogen content in BSCs, soil pH, Topographic Wetness Index and foreland location. Two-way analysis of variance followed by Tukey’s test revealed significant differences in studied environmental variables between habitat types and studied locations, showing that foreland soils still retain particular initial characters to differentiate them from tundra soil

    The lichenicolous fungi of the South Shetland Islands, Antarctica : species diversity and identification guide

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    This paper contributes 96 species to the biota of lichenicolous fungi in the South Shetland Islands archipelago. New to science are the following genera: Antarctosphaeria Alstrup & Olech, gen. nov., Dahawkswia Alstrup & Olech, gen. nov., Lichenohostes Alstrup & Olech, gen. nov., Llanorella Alstrup & Olech, gen. nov., Phaeosporodendron Alstrup & Olech, gen. nov., and Prostratomyces Alstrup & Olech, gen. nov. Additionally, 31 species are described as new to science. These are: Antarctosphaeria bireagens Alstrup & Olech, sp. nov., A. lichenicola Alstrup & Olech, sp. nov., Arthonia dufayelensis Alstrup & Olech, sp. nov., A. livingstonensis Alstrup & Olech, sp. nov., A. massalongiae Alstrup & Olech, sp. nov., A. pertusariicola Alstrup & Olech, sp. nov., A. rakusae Alstrup & Olech, sp. nov., Carbonea austroshetlandica Alstrup & Olech, sp. nov., Cercidospora pertusariicola Alstrup & Olech, sp. nov., Dactylospora antarctica Alstrup & Olech, sp. nov., D. haematommatis Alstrup & Olech, sp. nov., Dahawkswia lichenicola Alstrup & Olech, sp. nov., Dendrophoma acarosporae Alstrup & Olech, sp. nov., Didymellopsis antarctica Alstrup & Olech, sp. nov., Lichenohostes citrinospora Alstrup & Olech, sp. nov., Lichenostigma corymbosae Alstrup & Olech, sp. nov., Llanorella ramalinae Alstrup & Olech, sp. nov., Metasphaeria verrucosa Alstrup & Olech, sp. nov., Micarea lichenicola Alstrup & Olech, sp. nov., Phaeospora antarctica Alstrup & Olech, sp. nov., P. convolutae Alstrup & Olech, sp. nov., Phaeosporodendron badiae Alstrup & Olech, sp. nov., Phoma acarosporae Alstrup & Olech, sp. nov., Prostratomyces leprariae Alstrup & Olech, sp. nov., P. ochrolechiae Alstrup & Olech, sp. nov., P. rhizocarpicolae Alstrup & Olech, sp. nov., Rhagadostoma antarctica Alstrup & Olech, sp. nov., Sphaerellothecium placopsiicola Alstrup & Olech, sp. nov., Stigmidium placopsiicola Alstrup & Olech, sp. nov., Taeniolella frigidae Alstrup & Olech, sp. nov., and Tetramelas caloplacae Alstrup & Olech, sp. nov. Furthermore, a literature survey was undertaken, which resulted in the preparation of an identification guide for the lichenicolous species occurring in the South Shetlands Islands
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