990 resultados para terrain


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The shuttle radar topography mission (SRTM), was flow on the space shuttle Endeavour in February 2000, with the objective of acquiring a digital elevation model of all land between 60 degrees north latitude and 56 degrees south latitude, using interferometric synthetic aperture radar (InSAR) techniques. The SRTM data are distributed at horizontal resolution of 1 arc-second (similar to 30m) for areas within the USA and at 3 arc-second (similar to 90m) resolution for the rest of the world. A resolution of 90m can be considered suitable for the small or medium-scale analysis, but it is too coarse for more detailed purposes. One alternative is to interpolate the SRTM data at a finer resolution; it will not increase the level of detail of the original digital elevation model (DEM), but it will lead to a surface where there is the coherence of angular properties (i.e. slope, aspect) between neighbouring pixels, which is an important characteristic when dealing with terrain analysis. This work intents to show how the proper adjustment of variogram and kriging parameters, namely the nugget effect and the maximum distance within which values are used in interpolation, can be set to achieve quality results on resampling SRTM data from 3"" to 1"". We present for a test area in western USA, which includes different adjustment schemes (changes in nugget effect value and in the interpolation radius) and comparisons with the original 1"" model of the area, with the national elevation dataset (NED) DEMs, and with other interpolation methods (splines and inverse distance weighted (IDW)). The basic concepts for using kriging to resample terrain data are: (i) working only with the immediate neighbourhood of the predicted point, due to the high spatial correlation of the topographic surface and omnidirectional behaviour of variogram in short distances; (ii) adding a very small random variation to the coordinates of the points prior to interpolation, to avoid punctual artifacts generated by predicted points with the same location than original data points and; (iii) using a small value of nugget effect, to avoid smoothing that can obliterate terrain features. Drainages derived from the surfaces interpolated by kriging and by splines have a good agreement with streams derived from the 1"" NED, with correct identification of watersheds, even though a few differences occur in the positions of some rivers in flat areas. Although the 1"" surfaces resampled by kriging and splines are very similar, we consider the results produced by kriging as superior, since the spline-interpolated surface still presented some noise and linear artifacts, which were removed by kriging.

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Forest nurseries are essential for producing good quality seedlings, thus being a key element in the reforestation process. With increasing climate change awareness, nursery managers are looking for new tools that can help reduce the effects of their operations on the environment. The ZEPHYR project, funded by the European Commission under the Seventh Framework Programme (FP7), has the objective of finding new alternatives for nurseries by developing innovative zero-impact technologies for forest plant production. Due to their direct relationship to the energy consumption of the nurseries, one of the main elements addressed are the grow lights used for the pre-cultivation. New LED luminaires with a light spectrum tailored to the seedlings’ needs are being studied and compared against the traditional fluorescent lamps. Seedlings of Picea abies and Pinus sylvestris were grown under five different light spectra (one fluorescent and 4 LED) during 5 weeks with a photoperiod of 16 hours at 100 μmol∙m-2∙s-1 and 60% humidity. In order to evaluate if these seedlings were able cope with real field stress conditions, a forest field trial was also designed. The terrain chosen was a typical planting site in mid-Sweden after clear-cutting. Two vegetation periods after the outplanting, the seedlings that were pre-cultivated under the LED lamps have performed at least as well as those that were grown under fluorescent lights. These results show that there is a good  potential for lightning substitution in forestry nurseries.

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In February 2000, the new Victorian Labor Government announced that they were removing the western shard from Lab Architecture Studio's winning Melbourne Federation Square design. then under construction. The specific 'contested terrain' at the intersection of Flinders Street and Swanston Street Walk. Melbourne, allows the exploration of the politics of place construction over time, through an examination of Young and Jackson's Hotel [1861]. St Paul's Cathedral [1886). Flinders Street Station [1912]. the Westin Hotel [1999) and Federation Square. This site brings together architectural and social history, questions public space and identity, and looks at Melburnian's perceptions, attitudes and values. It further demonstrates that the fragmentation of the professions, and fragmentary histories. lead to the preservation of 'bits' of architecture and the destruction of the urban/landscape context, jeopardizing the Identity of place.

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Bullen and Parsons identify Anthony Browne's picture book Into the Forest as a re-gendered retelling of 'Little Red Riding Hood' that expresses recent assumptions about childhood, risk and the resources children need to survive in today's world. In Browne's version, the forest is the terrain in which a young male protagonist imaginatively explores his anxiety about his father's unexplained absence.

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These notes explore some of the background, the influences and pre-occupations at play in the construction of my short film Traum A Dream (Australia 6 minutes 2003) that was shown at the 2004 Double Dialogues Conference. This exercise thus places me in that terrain, that double dialogue between theory and practice. As both artist and commentator it also threatens to catch me hovering in that no-man’s land between the written word about the art and the artefact itself, judging my own folly.


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Freedom, autonomy, enslavement and coercion have a multitude of meanings which are determined by the writer’s discipline background and intent, even more so in the area of illicit drugs’ policy and treatment. This paper proposes to begin to untangle the multiplicity of meanings which are attached to two contrasting forms of illicit drugs treatment, harm minimisation and abstinence-based treatments. Both treatment regimes lay claim to the high moral ground in this regard - freedom and autonomy are explicit terms used in the rhetoric of both. How this can best be understood and what sociologists can contribute to the debates about illicit drug treatments is the terrain this paper traverses. It does this by laying out the different meanings of the terms in social theory and then by trying to understand the ‘truth’ claims of treatment proponents and using a Foucauldian perspective to critique these claims.

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Teleoperation has been used in many applications, allowing a human operator to remotely control a robotic system in order to perform a particular task. Recently haptic teleoperation has focused mainly on improving performance in remote manipulation tasks, however the haptic approach offers similar advantages for teleoperative control of the motion of a mobile robot. This paper describes a prototype system designed to facilitate haptic teleoperation of an all-terrain, articulated track mobile robot. This system utilizes a multi-modal user interface intended to improve operator immersion, reduce operator overload and improve teleoperative task performance. The system architecture facilitates implementation of an application-specific haptic augmentation algorithm in order to improve operator performance in challenging real-world tasks. The contributions of this work can be categorized as the custom mobile platform, teleoperator interface and haptic augmentation strategy.

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Traditionally, the control system of a modern teleoperated mobile robot consists of one or more two-dimensional joysticks placed on a control interface. While this simplistic interface allows an operator to remotely drive the platform, feedback is limited to visual information supplied by on-board cameras. Significant advances in the field of haptics have the potential to meaningfully enhance situational awareness of a remote robot. The focus of this research is the augmentation of Deakin University's OzBot trade MkIV mobile platform to include haptic control methodologies. Utilising the platform's inertial measurement unit, a remote operator has the ability to gain knowledge of the vehicle's operating performance and terrain while supplying a finer level of control to the drive motors. Our development of a generic multi-platform ActiveX allows the easy implementation of haptic force feedback to many computer based robot controllers. Furthermore, development of communication protocols has progressed with Joint Architecture for Unmanned Systems (JAUS) compliance in mind. The haptic force control algorithms are presented along with results highlighting the benefits of haptic operator feedback on the MklV OzBot trade chassis.

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In the 2,500,000 km2 Lake Chad Basin in central Africa, the 2000 Shuttle Radar Topographic Mission (SRTM) data have been used to supplement the existing topographic data. SRTM data produce much sharper images of the region's topography and provide new insights into debates about the nature and extent of late Quaternary Lake Chad. This paper shows that the accuracy of SRTM30, the recently released 30 arc seconds topographic data from SRTM, largely surpasses that of previous global Digital Elevation Models (DEMs) available in the region. Using a GIS we identified from SRTM30 elevation data key features in the landscape topography providing further evidence for the existence of a Megalake Chad. The SRTM30 data corroborate the presence of two ancient shorelines associated with stillstands of the paleolake at the elevation of the Mayo Kebbi and Bahr el Ghazal spillovers. We found a general flattening of the topography in the region covered by Megalake Chad which is most likely the result of wave-cut action. The SRTM30 data show that the remains of the highest paleoshoreline have a constant elevation of 325 ± 5 m amsl. At its maximum extent, Megalake Chad had an area of about 340 000 km2 (only 8% less than the present-day world's largest lake, the Caspian Sea). The SRTM30 data also revealed ancient drainage networks in the Sahara that lead to Megalake Chad. We compiled available 14C dates to constrain Holocene Megalake Chad events. The results presented in this paper have significant consequences for improving our knowledge of regional paleohydrology and continental climate change. This study is also the first step for a GIS-based reconstruction of late Quaternary paleohydrology in tropical Africa.

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This paper presents an application of Microsoft Robotics Studio (MSRS) in which a team of six four wheel drive, ground based robots explore and map simulated terrain. The user has the ability to modify the terrain and assign destination objectives to the team while the simulation is running. The terrain is initially generated using a gray scale image, in which the intensity of each pixel in the image gives an altitude datum. The robots start with no knowledge of their surroundings, and map the terrain as they attempt to reach user-defined target objectives. The mapping process simulates the use of common sensory hardware to determine datum points, including provision for field of view, detection range, and measurement accuracy. If traversal of a mapped area is indicated by the users’ targeting commands, path planning heuristics developed for MSRS by the author in earlier work are used to determine an efficient series of waypoints to reach the objective. Mutability of terrain is also explored- the user is able to modify the terrain without stopping the simulation. This forces the robots to adapt to changing environmental conditions, and permits analysis of the robustness of mapping algorithms used when faced with a changing world.

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Wildlife managers are often faced with the difficult task of determining the distribution of species, and their preferred habitats, at large spatial scales. This task is even more challenging when the species of concern is in low abundance and/or the terrain is largely inaccessible. Spatially explicit distribution models, derived from multivariate statistical analyses and implemented in a geographic information system (GIS), can be used to predict the distributions of species and their habitats, thus making them a useful conservation tool. We present two such models: one for a dasyurid, the Swamp Antechinus (Antechinus minimus), and the other for a ground-dwelling bird, the Rufous Bristlebird (Dasyornis broadbenti), both of which are rare species occurring in the coastal heathlands of south-western Victoria. Models were generated using generalized linear modelling (GLM) techniques with species presence or absence as the independent variable and a series of landscape variables derived from GIS layers and high-resolution imagery as the predictors. The most parsimonious model, based on the Akaike Information Criterion, for each species then was extrapolated spatially in a GIS. Probability of species presence was used as an index of habitat suitability. Because habitat fragmentation is thought to be one of the major threats to these species, an assessment of the spatial distribution of suitable habitat across the landscape is vital in prescribing management actions to prevent further habitat fragmentation.

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Introducing Evidence Based Health Policy: Problems and Possibilities, Section 1: What is the Problem?, 1: Competing Rationalities: Evidence based Health Policy, 2: Beyond Two Communities, Section 2: What does Evidence Mean?, 3: Evidence based Medicine - The Medical Profession and Health Policy, 4: Mind The Gap: Assessing the Quality of Evidence for Public Health Problems, 5: Health Policy and Normative Analysis: Ethics, Evidence and Politics, 6: What is New in Health Information? Evidence for Health Consumers and Policy Making, 7: From Evidence based Medicine to Evidence based Public Health, Section 3: Policy Case Studies, 8: The Viagra Affair: Evidence as the Terrain for Competing Partners, 9: Folate Fortification: A Case Study of Public Health Policy-Making in a Food Regulation Setting, 10: The Supply and Safety of Blood and Blood Products - Evidence, Risk and Policy, 11: The Development of Nurse Practitioner Policy, 12: Creating Healthy Public Policy for Oral Health: How was the Evidence Used?, 13: Regulation of Traditional Chinese Medicine in Victoria, 14: The Victorian Primary Health Care Reforms: A Case Study of Evidence-based Policy Making, 15: Evidence-based Practice in the Australian Drug Policy Community, 16: Challenging the Evidence - Women's Health Policy in Australia, 17: Evidence and Aboriginal Health Policy, 18: The Limits to Technical Rationality in the Health Inequalities Policy Process, 19: Evidence-based policy: A Technocratic Wish in a Political World, Section 4: Is the transfer of evidence into policy possible?, 20: The Community Model of Research Transfer, 21: Getting Research Transfer into Policy and Practice in Maternity Care, 22: Improving the Research and Policy Partnership: An Agenda for Research Transfer and Governance, 23: Framing and Taming 'Wicked' Problems

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This paper seeks to expand on environmental design understood in purely
instrumentalist terms. It argues that current environmental emergencies in Austlalia and elsewhere are requiring alternative strategies of response, and proposes the terrain of poetic w'ork as offering new insights in the field of sustainability practice. lt draws upon two place-making projects to advance a theory of environmental design that is poetically guided.

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Bangladesh introduced open and distance learning as a means of providing education for people in isolated and remote locations through the establishment of the Bangladesh Open University (BOU). The broad aim of the BOU is to provide flexible and needs-based education to those unable or not wishing to enter conventional educational institutions. The BOU is presently the only university in Bangladesh to provide mass education and also to provide continuing education and professional and technical education to support the existing educational system. The BOU has a mission that encompasses secondary and higher levels of education. BOU operates its programs through a centralised academic and administrative staff, and regional and local offices throughout Bangladesh that organise local tutorials and distribute information and materials. BOU has adult students in all parts of the country, and most of the students live in rural areas. They need support that is appropriate to their local circumstances. Using an interpretive approach, this research examines the support needs of students studying for the Secondary School Certificate and the Bachelor of Education, assesses the effectiveness of current support services and explores alternatives to the current system. The underlying assumption is that support needs to be appropriate to the country’s culture and circumstances, and useful and feasible from the perspectives of students, staff, administrators and senior university officials. To investigate the appropriate support for distance education students, this research was conducted in four sample regions. Two were selected from areas of sparse population where the terrain makes transport difficult and two from areas that are more densely populated and where transport is easier. A questionnaire survey and focus groups were conducted with students, focus groups with local staff and interviews with Regional Directors within the four sample regions. Interviews were also undertaken with central University senior staff to get their perspectives on current and future policies for student support.

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Interculturality and intercultural identity is a local effect of the global movement and mixing of people, and those of intercultural identities constitute the fastest growing sector of the Australian population. In an age of globalisation and diversification, what does identity mean for those situated in-between governing notions of racial/ethnic formations, and how is intercultural identity experienced? For those informed by (at least) two cultures, what does multiculturalism, ethnicity and 'Australianness' mean, and where are these individuals positioned in relation to these structures? These questions have critical implications for the Australian nation. Within Australian discourses, interculturality and intercultural identity, in particular, has historically been excluded, rendered invisible. This dissertation is, therefore, one of facilitating visibility. Using the hyphens as a conceptual tool, I argue that in this age of accelerating globalisation the hyphens both makes visible and is made visible by interculturality. The hyphens is that grey and fluid site of intersection between structures of identity and is characterised by liminality - contestation, uncertainty, fundamentally ambivalence. Experiences of liminality, however, dissolve in any given time, opening up new terrain for creativity. Some of these emerging and creative forms of identity, as instigated by interculturality, are explored. Based on interviews with 20 daughters (and their mothers) from intercultural unions, this dissertation places intercultural identity on the Australian conceptual map and analyses the unique position occupied by those with an intercultural identity in their relationship with governing discursive formations of race/ethnicity, embodiment, nation and culture. In essence, the dissertation is concerned with examining the ways in which discursive identity structures intersect with subjective experience, and with the ways in which those with an intercultural identity negotiate those structures and their social relations. This examination raises the fundamental question: is the modernist notion of the material realities of individual lives reconcilable with the poststructural notion of identity as always located in discourse. This modernist/postmodernist tension permeates the dissertation.