881 resultados para Information Environment
Resumo:
Tidal stream turbines could have several direct impacts upon pursuit-diving seabirds foraging within tidal stream environments (mean horizontal current speeds > 2 ms−1), including collisions and displacement. Understanding how foraging seabirds respond to temporally variable but predictable hydrodynamic conditions immediately around devices could identify when interactions between seabirds and devices are most likely to occur; information which would quantify the magnitude of potential impacts, and also facilitate the development of suitable mitigation measures. This study uses shore-based observational surveys and Finite Volume Community Ocean Model outputs to test whether temporally predictable hydrodynamic conditions (horizontal current speeds, water elevation, turbulence) influenced the density of foraging black guillemots Cepphus grylle and European shags Phalacrocorax aristotelis in a tidal stream environment in Orkney, United Kingdom, during the breeding season. These species are particularly vulnerable to interactions with devices due to their tendency to exploit benthic and epi-benthic prey on or near the seabed. The density of both species decreased as a function of horizontal current speeds, whereas the density of black guillemots also decreased as a function of water elevation. These relationships could be linked to higher energetic costs of dives in particularly fast horizontal current speeds (>3 ms−1) and deeper water. Therefore, interactions between these species and moving components seem unlikely at particularly high horizontal current speeds. Combining this information, with that on the rotation rates of moving components at lower horizontal current speeds, could be used to assess collision risk in this site during breeding seasons. It is also likely that moderating any device operation during both lowest water elevation and lowest horizontal current speeds could reduce the risk of collisions for these species in this site during this season. The approaches used in this study could have useful applications within Environmental Impact Assessments, and should be considered when assessing and mitigating negative impacts from specific devices within development sites.
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This paper is part of a special issue of Applied Geochemistry focusing on reliable applications of compositional multivariate statistical methods. This study outlines the application of compositional data analysis (CoDa) to calibration of geochemical data and multivariate statistical modelling of geochemistry and grain-size data from a set of Holocene sedimentary cores from the Ganges-Brahmaputra (G-B) delta. Over the last two decades, understanding near-continuous records of sedimentary sequences has required the use of core-scanning X-ray fluorescence (XRF) spectrometry, for both terrestrial and marine sedimentary sequences. Initial XRF data are generally unusable in ‘raw-format’, requiring data processing in order to remove instrument bias, as well as informed sequence interpretation. The applicability of these conventional calibration equations to core-scanning XRF data are further limited by the constraints posed by unknown measurement geometry and specimen homogeneity, as well as matrix effects. Log-ratio based calibration schemes have been developed and applied to clastic sedimentary sequences focusing mainly on energy dispersive-XRF (ED-XRF) core-scanning. This study has applied high resolution core-scanning XRF to Holocene sedimentary sequences from the tidal-dominated Indian Sundarbans, (Ganges-Brahmaputra delta plain). The Log-Ratio Calibration Equation (LRCE) was applied to a sub-set of core-scan and conventional ED-XRF data to quantify elemental composition. This provides a robust calibration scheme using reduced major axis regression of log-ratio transformed geochemical data. Through partial least squares (PLS) modelling of geochemical and grain-size data, it is possible to derive robust proxy information for the Sundarbans depositional environment. The application of these techniques to Holocene sedimentary data offers an improved methodological framework for unravelling Holocene sedimentation patterns.
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In this paper, we propose three relay selection schemes for full-duplex heterogeneous networks in the presence of multiple cognitive radio eavesdroppers. In this setup, the cognitive small-cell nodes (secondary network) can share the spectrum licensed to the macro-cell system (primary network) on the condition that the quality-of-service of the primary network is always satisfied subjected to its outage probability constraint. The messages are delivered from one small-cell base station to the destination with the help of full-duplex small-cell base stations, which act as relay nodes. Based on the availability of the network’s channel state information at the secondary information source, three different selection criteria for full-duplex relays, namely: 1) partial relay selection; 2) optimal relay selection; and 3) minimal self-interference relay selection, are proposed. We derive the exact closed-form and asymptotic expressions of the secrecy outage probability for the three criteria under the attack of non-colluding/colluding eavesdroppers. We demonstrate that the optimal relay selection scheme outperforms the partial relay selection and minimal self-interference relay selection schemes at the expense of acquiring full channel state information knowledge. In addition, increasing the number of the full-duplex small-cell base stations can improve the security performance. At the illegitimate side, deploying colluding eavesdroppers and increasing the number of eavesdroppers put the confidential information at a greater risk. Besides, the transmit power and the desire outage probability of the primary network have great influences on the secrecy outage probability of the secondary network.
Resumo:
GUEDES, Clediane de Araújo; FARIAS, Gabriela Belmont de. Information literacy: uma análise nas bibliotecas escolares da rede privada em Natal / RN. Revista Digital de Biblioteconomia e Ciência da Informação, Campinas, v. 4, n. 2, p. 110-133, jan./jun. 2007
Resumo:
SOUZA, Rodrigo B. ; MEDEIROS, Adelardo A. D. ; NASCIMENTO, João Maria A. ; GOMES, Heitor P. ; MAITELLI, André L. A Proposal to the Supervision of Processes in an Industrial Environment with Heterogeneous Systems. In: INTERNATIONAL CONFERENCE OF THE IEEEOF THE INDUSTRUI ELECTRONICS SOCIETY,32., Paris, 2006, Paris. Anais... Paris: IECON, 2006
Resumo:
The Computing Division of the Business School at University College Worcester provides computing and information technology education to a range of undergraduate students. Topics include various approaches to programming, artificial intelligence, operating systems and digital technologies. Each of these has its own potentially conflicting requirements for a pedagogically sound programming environment. This paper describes an endeavor to develop a common programming paradigm across all topics. This involves the combined use of autonomous robots and Java simulations.
Resumo:
It is now generally accepted that cyber crime represents a big threat to organisations, and that they need to take appropriate action to protect their valuable information assets. However, current research shows that, although small businesses understand that they are potentially vulnerable, many are still not taking sufficient action to counteract the threat. Last year, the authors sought, through a more generalised but categorised attitudinal study, to explore the reasons why smaller SMEs in particular were reluctant to engage with accepted principles for protecting their data. The results showed that SMEs understood many of the issues. They were prepared to spend more but were particularly suspicious about spending on information assurance. The authors’ current research again focuses on SME attitudes but this time the survey asks only questions directly relating to information assurance and the standards available, in an attempt to try to understand exactly what is causing them to shy away from getting the badge or certificate that would demonstrate to customers and business partners that they take cyber security seriously. As with last year’s study, the results and analysis provide useful pointers towards the broader business environment changes that might cause SMEs to be more interested in working towards an appropriate cyber security standard.
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Abstract : Images acquired from unmanned aerial vehicles (UAVs) can provide data with unprecedented spatial and temporal resolution for three-dimensional (3D) modeling. Solutions developed for this purpose are mainly operating based on photogrammetry concepts, namely UAV-Photogrammetry Systems (UAV-PS). Such systems are used in applications where both geospatial and visual information of the environment is required. These applications include, but are not limited to, natural resource management such as precision agriculture, military and police-related services such as traffic-law enforcement, precision engineering such as infrastructure inspection, and health services such as epidemic emergency management. UAV-photogrammetry systems can be differentiated based on their spatial characteristics in terms of accuracy and resolution. That is some applications, such as precision engineering, require high-resolution and high-accuracy information of the environment (e.g. 3D modeling with less than one centimeter accuracy and resolution). In other applications, lower levels of accuracy might be sufficient, (e.g. wildlife management needing few decimeters of resolution). However, even in those applications, the specific characteristics of UAV-PSs should be well considered in the steps of both system development and application in order to yield satisfying results. In this regard, this thesis presents a comprehensive review of the applications of unmanned aerial imagery, where the objective was to determine the challenges that remote-sensing applications of UAV systems currently face. This review also allowed recognizing the specific characteristics and requirements of UAV-PSs, which are mostly ignored or not thoroughly assessed in recent studies. Accordingly, the focus of the first part of this thesis is on exploring the methodological and experimental aspects of implementing a UAV-PS. The developed system was extensively evaluated for precise modeling of an open-pit gravel mine and performing volumetric-change measurements. This application was selected for two main reasons. Firstly, this case study provided a challenging environment for 3D modeling, in terms of scale changes, terrain relief variations as well as structure and texture diversities. Secondly, open-pit-mine monitoring demands high levels of accuracy, which justifies our efforts to improve the developed UAV-PS to its maximum capacities. The hardware of the system consisted of an electric-powered helicopter, a high-resolution digital camera, and an inertial navigation system. The software of the system included the in-house programs specifically designed for camera calibration, platform calibration, system integration, onboard data acquisition, flight planning and ground control point (GCP) detection. The detailed features of the system are discussed in the thesis, and solutions are proposed in order to enhance the system and its photogrammetric outputs. The accuracy of the results was evaluated under various mapping conditions, including direct georeferencing and indirect georeferencing with different numbers, distributions and types of ground control points. Additionally, the effects of imaging configuration and network stability on modeling accuracy were assessed. The second part of this thesis concentrates on improving the techniques of sparse and dense reconstruction. The proposed solutions are alternatives to traditional aerial photogrammetry techniques, properly adapted to specific characteristics of unmanned, low-altitude imagery. Firstly, a method was developed for robust sparse matching and epipolar-geometry estimation. The main achievement of this method was its capacity to handle a very high percentage of outliers (errors among corresponding points) with remarkable computational efficiency (compared to the state-of-the-art techniques). Secondly, a block bundle adjustment (BBA) strategy was proposed based on the integration of intrinsic camera calibration parameters as pseudo-observations to Gauss-Helmert model. The principal advantage of this strategy was controlling the adverse effect of unstable imaging networks and noisy image observations on the accuracy of self-calibration. The sparse implementation of this strategy was also performed, which allowed its application to data sets containing a lot of tie points. Finally, the concepts of intrinsic curves were revisited for dense stereo matching. The proposed technique could achieve a high level of accuracy and efficiency by searching only through a small fraction of the whole disparity search space as well as internally handling occlusions and matching ambiguities. These photogrammetric solutions were extensively tested using synthetic data, close-range images and the images acquired from the gravel-pit mine. Achieving absolute 3D mapping accuracy of 11±7 mm illustrated the success of this system for high-precision modeling of the environment.
Resumo:
GUEDES, Clediane de Araújo; FARIAS, Gabriela Belmont de. Information literacy: uma análise nas bibliotecas escolares da rede privada em Natal / RN. Revista Digital de Biblioteconomia e Ciência da Informação, Campinas, v. 4, n. 2, p. 110-133, jan./jun. 2007
Resumo:
SOUZA, Rodrigo B. ; MEDEIROS, Adelardo A. D. ; NASCIMENTO, João Maria A. ; GOMES, Heitor P. ; MAITELLI, André L. A Proposal to the Supervision of Processes in an Industrial Environment with Heterogeneous Systems. In: INTERNATIONAL CONFERENCE OF THE IEEEOF THE INDUSTRUI ELECTRONICS SOCIETY,32., Paris, 2006, Paris. Anais... Paris: IECON, 2006
Resumo:
With the prevalence of smartphones, new ways of engaging citizens and stakeholders in urban planning and govern-ance are emerging. The technologies in smartphones allow citizens to act as sensors of their environment, producing and sharing rich spatial data useful for new types of collaborative governance set-ups. Data derived from Volunteered Geographic Information (VGI) can support accessible, transparent, democratic, inclusive, and locally-based governance situations of interest to planners, citizens, politicians, and scientists. However, there are still uncertainties about how to actually conduct this in practice. This study explores how social media VGI can be used to document spatial tendencies regarding citizens’ uses and perceptions of urban nature with relevance for urban green space governance. Via the hashtag #sharingcph, created by the City of Copenhagen in 2014, VGI data consisting of geo-referenced images were collected from Instagram, categorised according to their content and analysed according to their spatial distribution patterns. The results show specific spatial distributions of the images and main hotspots. Many possibilities and much potential of using VGI for generating, sharing, visualising and communicating knowledge about citizens’ spatial uses and preferences exist, but as a tool to support scientific and democratic interaction, VGI data is challenged by practical, technical and ethical concerns. More research is needed in order to better understand the usefulness and application of this rich data source to governance.
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This thesis examines the spatial and temporal variation in nitrogen dioxide (NO2) levels in Guernsey and the impacts on pre-existing asthmatics. Whilst air quality in Guernsey is generally good, the levels of NO2 exceed UK standards in several locations. The evidence indicates that people suffering from asthma have exacerbation of their symptoms if exposed to elevated levels of air pollutants including NO2, although this research has never been carried out in Guernsey before. In addition, exposure assessment of individuals is rarely carried out and research in this area is limited due to the complexity of undertaking such a study, which will include a combination of exposures in the home, the workplace and ambient exposures, which vary depending on the individual daily experience. For the first time in Guernsey, this research has examined NO2 levels in correlation with asthma patient admissions to hospital, assessment of NO2 exposures in typical homes and typical workplaces in Guernsey. The data showed a temporal correlation between NO2 levels and the number of hospital admissions and the trend from 2008-2012 was upwards. Statistical analysis of the data did not show a significant linear correlation due to the small size of the data sets. Exposure assessment of individuals showed a spatial variation in exposures in Guernsey and assessment in indoor environments showed that real-time analysis of NO2 levels needs to be undertaken if indoor micro environments for NO2 are the be assessed adequately. There was temporal and spatial variation in NO2 concentrations measured using diffusion tubes, which provide a monthly mean value, and analysers measuring NO2 concentrations in real time. The research shows that building layout and design are important factors for good air flow and ventilation and the dispersion of NO2 indoors. Environmental Health Officers have statutory responsibilities for ambient air quality, hygiene of buildings and workplace environments and this role needs to be co-ordinated with healthcare professionals to improve health outcomes for asthmatics. The outcome of the thesis was the development of a risk management framework for pre-existing asthmatics at work for use by regulators of workplaces and an information leaflet to assist in improving health outcomes for asthmatics in Guernsey.
Resumo:
Urban wayfinding technology offers many possibilities by which older people and mobility-impaired users can overcome the barriers encountered on every-day journeys in the built environment. Previous work has highlighted the extent to which personal mobility and independence are significant determinants of the quality of life amongst both elderly and visually impaired groups. The paper outlines the development of the auditory location finder (ALF), which is a beacon-based local information system designed to enhance the wayfinding activities of these, and potentially other, user-groups in the community. The proposed system provides the user with an audio message, which is obtained on request via a small portable hand unit. The messages inform the user of their whereabouts and give information about the area that they are currently in. The development of the device involves issues such as message content and structure, route choice, orientation, landmarks, clues and the extent of user reliance on technology. Preliminary trials have been carried out in a UK city and have obtained initial user feedback to help underpin the technological development of the device and its potential application. The paper concludes by outlining the importance of new urban technology and the way in which such local information systems can potentially contribute to overcoming particular patterns of exclusion experienced by mobility-impaired groups, such as the visually impaired
Resumo:
Starting from the relationship between urban planning and mobility management, TeMA has gradually expanded the view of the covered topics, always remaining in the groove of rigorous scientific in-depth analysis. During the last two years a particular attention has been paid on the Smart Cities theme and on the different meanings that come with it. The last section of the journal is formed by the Review Pages. They have different aims: to inform on the problems, trends and evolutionary processes; to investigate on the paths by highlighting the advanced relationships among apparently distant disciplinary fields; to explore the interaction’s areas, experiences and potential applications; to underline interactions, disciplinary developments but also, if present, defeats and setbacks. Inside the journal the Review Pages have the task of stimulating as much as possible the circulation of ideas and the discovery of new points of view. For this reason the section is founded on a series of basic’s references, required for the identification of new and more advanced interactions. These references are the research, the planning acts, the actions and the applications, analysed and investigated both for their ability to give a systematic response to questions concerning the urban and territorial planning, and for their attention to aspects such as the environmental sustainability and the innovation in the practices. For this purpose the Review Pages are formed by five sections (Web Resources; Books; Laws; Urban Practices; News and Events), each of which examines a specific aspect of the broader information storage of interest for TeMA.
Resumo:
The influence of information about trip time variability, personal benefits, or environmental harm from cars or public transportation on commuting mode choice (car or subway) is examined in an experimental study. In addition to these experimentally manipulated variables, the influence of prior attitudes towards the subway was verified. The sample is made up of habitual users of the car to travel to work (N = 220, age M = 37.4, SD = 8.1, 63.2% women). The results show that providing information about the advantages of public transportation, as well as prior attitudes towards the subway, decrease the preference, choice, and perceived control of car use. Of the experimentally manipulated variables, information about the variability of trip time had the greatest influence. These results highlight the importance of taking into account these variables to implement institutional campaigns to reduce car use as transportation mode.