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UAV trajectory optimisation in smart cities using modified A* algorithm combined with Haversine and Vincenty formulas
It is anticipated that the backbone of Smart Cities concerning automation and networking will be formed by Unmanned Aerial Vehicles in the imminent future. Therefore, our research focuses on developing advanced microcontrollers embedded with Artificial Intelligence techniques for self-governing Unmanned Aerial Vehicles. The main objective of this research was to enable full automation for the execution of flight paths with non-trivial sequences that will be performed with centimetre-level accuracy. Also, by utilising dynamic flight plans and trajectories, we aim to secure autonomous aviation based on norms, with control loops and fundamental constraints. More specifically, we evolved a novel algorithmic technique for trajectory optimisation, which deploys a modification to the A* search algorithm, implemented by the Haversine formula and enhances accuracy using Vincenty’s formula. Furthermore, realistic values for trajectory optimisation and obstacle avoidance were found through the implementation of a simulative investigation. The outcomes of our methodology indicate that the safety constraints associated with the integration of Unmanned Aerial Vehicles in the urban environment can be significantly mitigated. Consequently, their effectiveness will be increased in realising their diverse operations and capabilities
Interacción entre clima y ocupación humana en la configuración del paisaje vegetal del Parque Nacional de Aigüestortes i Estany de Sant Maurici a lo largo de los últimos 15.000 años
The vegetation of the National Park of Aigüestortes i Estany de St Maurici is the result of an interaction between climate, plant community dynamics and the human occupation of the territory. The OCUPAproject aimed to reconstruct this interaction across the last millennia combining methods from palaeoecology and archaeology. The study focused primarily on the Sant Nicolau valley and built on the multidisciplinary analysis of the sedimentary archive of two lakes (Llebreta and Redó) and a number of archaeological sites located in shelters and outdoors. There is archaeological evidence of human presencesince 9000 yr cal BP, and a continuous record since 7500 yr cal BP. At early stages, humans transformed the surroundings of the shelters occupied and lithic tools indicate contacts with locations far away (i.e.,the Ebro plains). Since more than 3000 years ago, there has been human impact on the vegetation withoutinterruption until present. Initially, the impacts were mostly related to livestock: use of fire to open grazing lands, soil erosion and, during the medieval period, forestry and eutrophication of lakes. The agriculture impact in the lower part of the valley (e.g., Llebreta) occurred about 2100 yr ago, although some cereal grains and tools for harvesting have been found for the Neolithic. In the medieval period, the impact was higher than during the last centuries. In general, the changes in the human land use approximately follow the major changes in climate, but the specific causal link is likely related to the social and cultural dynamics of a broader territory since the Neolithic
River Restoration in Spain: Theoretical and Practical Approach in the Context of the European Water Framework Directive.
River restoration is becoming a priority in many countries because of increasing the awareness of environmental degradation. In Europe, the EU Water Framework Directive (WFD) has significantly reinforced river restoration, encouraging the improvement of ecological status for water bodies. To fulfill the WFD requirements, the Spanish Ministry of the Environment developed in 2006 a National Strategy for River Restoration whose design and implementation are described in this paper. At the same time many restoration projects have been conducted, and sixty of them have been evaluated in terms of stated objectives and pressures and implemented restoration measures. Riparian vegetation enhancement, weir removal and fish passes were the most frequently implemented restoration measures, although the greatest pressures came from hydrologic alteration caused by flow regulation for irrigation purposes. Water deficits in quantity and quality associated with uncontrolled water demands seriously affect Mediterranean rivers and represent the main constraint to achieving good ecological status of Spanish rivers, most of them intensively regulated. Proper environmental allocation of in-stream flows would need deep restrictions in agricultural water use which seem to be of very difficult social acceptance. This situation highlights the need to integrate land-use and rural development policies with water resources and river management, and identifies additional difficulties in achieving the WFD objectives and good ecological status of rivers in Mediterranean countries
Clinical and demographic features of patients with dementia attended in a tertiary outpatient clinic
Keep off the grass?:Cannabis, cognition and addiction
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.In an increasing number of states and countries, cannabis now stands poised to join alcohol and tobacco as a legal drug. Quantifying the relative adverse and beneficial effects of cannabis and its constituent cannabinoids should therefore be prioritized. Whereas newspaper headlines have focused on links between cannabis and psychosis, less attention has been paid to the much more common problem of cannabis addiction. Certain cognitive changes have also been attributed to cannabis use, although their causality and longevity are fiercely debated. Identifying why some individuals are more vulnerable than others to the adverse effects of cannabis is now of paramount importance to public health. Here, we review the current state of knowledge about such vulnerability factors, the variations in types of cannabis, and the relationship between these and cognition and addiction.This work was supported by grants from the US National Institutes of Health to L.H.P. (AA020404, AA006420, AA022249 and AA017447) and by grants from the UK Medical Research Council to H.V.C. and C.J.A.M. (G0800268; MR/K015524/1)
Secure Smart Homes: Opportunities and challenges
The Smart Home concept integrates smart applications in the daily human life. In recent years, Smart Homes have increased security and management challenges due to the low capacity of small sensors, multiple connectivity to the Internet for efficient applications (use of big data and cloud computing), and heterogeneity of home systems, which require inexpert users to configure devices and micro-systems. This article presents current security and management approaches in Smart Homes and shows the good practices imposed on the market for developing secure systems in houses. At last, we propose future solutions for efficiently and securely managing the Smart Homes
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