1000 resultados para environmental sounds


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This paper presents an approach to promote the integrity of perception systems for outdoor unmanned ground vehicles (UGV) operating in challenging environmental conditions (presence of dust or smoke). The proposed technique automatically evaluates the consistency of the data provided by two sensing modalities: a 2D laser range finder and a millimetre-wave radar, allowing for perceptual failure mitigation. Experimental results, obtained with a UGV operating in rural environments, and an error analysis validate the approach.

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This work aims to contribute to the reliability and integrity of perceptual systems of unmanned ground vehicles (UGV). A method is proposed to evaluate the quality of sensor data prior to its use in a perception system by utilising a quality metric applied to heterogeneous sensor data such as visual and infrared camera images. The concept is illustrated specifically with sensor data that is evaluated prior to the use of the data in a standard SIFT feature extraction and matching technique. The method is then evaluated using various experimental data sets that were collected from a UGV in challenging environmental conditions, represented by the presence of airborne dust and smoke. In the first series of experiments, a motionless vehicle is observing a ’reference’ scene, then the method is extended to the case of a moving vehicle by compensating for its motion. This paper shows that it is possible to anticipate degradation of a perception algorithm by evaluating the input data prior to any actual execution of the algorithm.

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Explosive ordnance disposal (EOD) technicians are required to wear protective clothing to protect themselves from the threat of overpressure, fragmentation, impact and heat. The engineering requirements to minimise these threats results in an extremely heavy and cumbersome clothing ensemble that increases the internal heat generation of the wearer, while the clothing’s thermal properties reduce heat dissipation. This study aimed to evaluate the heat strain encountered wearing EOD protective clothing in simulated environmental extremes across a range of differing work intensities. Eight healthy males [age 25±6 years (mean ± sd), height 180±7 cm, body mass 79±9 kg, V˙O2max 57±6 ml.kg−1.min−1] undertook nine trials while wearing an EOD9 suit (weighing 33.4 kg). The trials involved walking on a treadmill at 2.5, 4 and 5.5 km⋅h−1 at each of the following environmental conditions, 21, 30 and 37°C wet bulb globe temperature (WBGT) in a randomised controlled crossover design. The trials were ceased if the participants’ core temperature reached 39°C, if heart rate exceeded 90% of maximum, if walking time reached 60 minutes or due to fatigue/nausea. Tolerance times ranged from 10–60 minutes and were significantly reduced in the higher walking speeds and environmental conditions. In a total of 15 trials (21%) participants completed 60 minutes of walking; however, this was predominantly at the slower walking speeds in the 21°C WBGT environment. Of the remaining 57 trials, 50 were ceased, due to attainment of 90% maximal heart rate. These near maximal heart rates resulted in moderate-high levels of physiological strain in all trials, despite core temperature only reaching 39°C in one of the 72 trials.

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OBJECTIVE Interest is growing in promoting utility cycling (i.e., for transport) as a means of incorporating daily physical activity (PA) into people’s lives, but little is known about correlates of utility cycling. Our primary aim was to examine cross-sectional relationships between socio-economic characteristics, neighborhood environment perceptions and psychological disposition with utility cycling (with or without additional recreational cycling). A secondary aim was to compare these relationships with those for recreation-only cycling. METHOD Baseline survey data (2007) from 10,233 participants in HABITAT, a multilevel longitudinal study of PA, sedentary behavior, and health in Brisbane adults aged 40-65 years, were analysed using multinomial regression modelling. RESULTS Greater income, habitual PA, and positive beliefs about PA were associated with utility and recreation-only cycling (p<0.05). Always having vehicle access and not in the labor force were associated with recreation-only cycling (p<0.05). Some or no vehicle access, part-time employment, and perceived environmental factors (little crime, few cul-de-sacs, nearby transport and recreational destinations) were associated with utility cycling (p<0.05). CONCLUSION Our findings suggest differences in associations between socio-economic, neighborhood perceptions and psychological factors and utility and recreation-only cycling in Brisbane residents aged 40-65 years. Tailored approaches appear to be required to promote utility and recreational cycling.

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These wordless songs were composed as music first, and soundtrack second. There is a difference. A soundtrack will always be connected with whatever it is accompanying. Music doesn’t neccessarily need to reference anything else. The Empty City transformed a picture book into a non-verbal performance combining the live and animated. Without spoken words the show would dance on the dangerous intersection of music, image and action. In both theatre and film (and this production drew on both traditions) soundtrack and music are often added on at the end when everything’s been pre-determined, a passive, responsive mode for such a powerful artform. It’s literally added in ‘post’. In The Empty City, music was present from its inception and grew with the show. It was active in process and product. It frequently led rehearsals and shaped other key decisions in virtual and live performance. Rather than tailor-make music towards pre-determined moments, independent compositions created without specific reference to narrative experimented with the creation of a flock of small musical pieces. I was interested in seeing how they flew and where they roosted, rather than having them born and raised in (narrative) captivity. The sonic palette is largely acoustic, incorporating ukulele, prepared piano and supported by a range of other elements tending towards electronica. Eventually more than seventy pieces of music were made for this show, twice the number used. These pieces were then placed in relation to the emerging scenes, then adapted in duration, texture and progression to develop a relationship with the scene. In this way, music (even when it’s synced) has a conversation with a performance, an exchange that may result in surprise rather than fulfillment of expectation. Leitmotif emerged from loops and layers, as the pieces of music ‘conversed’ with each other, rather than being premeditated and imposed. Nineteen of these tracks are compiled for this release, which finds the compositions (which progressed through many versions) poised at the moment between their fullest iteration as ‘music’ and their editing and full incorporation into a sychronised soundtrack. They are released as the began: as 'music-alone' (Kivy) In picture-book writing, the mutual interplay of text and image is sometimes referred to as interanimation , and this is the kind of symbiosis this project sought in the creation of the soundtrack. Reviewers of the noted the important role of the soundtrack in two separate productions of The Empty City: “The original score…takes centre stage” (Borhani, 2013) “…swept up in its repetition of sounds and images, like a Bach fugue” (Zampatti, 2013)

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Despite a wide acceptance that primary producers in Australia subscribe to a stewardship ethic, land and water degradation remains an ongoing problem. Recent calculations suggest that the economic cost of Australia's environmental degradation is amounting to more than $A3.5 billion a year with an estimated cost of managing (not overcoming) problems of salinity, acidification, soil erosion totalling $A60 billion over the next decade. This paper argues that stewardship itself is an unsatisfactory concept when looking to landholders to respond to environmental problems, for rarely does the attitude of stewardship translate into behaviours of improving natural resource management practices on private land. Whilst there is some acceptance of the environmental problem among primary producers, a number of external constraints may also impede the uptake of conservation-orientated practices. In light of the prevailing accounts of poor adoption of sustainable practices a number of policy options are reviewed in this paper, including formal regional partnerships, regulatory frameworks and market-based measures. It is concluded that the contentious nature of some of these new opportunities for change will mean that any moves aimed at reversing environmental degradation in Australia will be slow.

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This article investigates the extent to which the purported greening of food retailing and consumption in Australia is consistent with the development of a corporate-environmental food regime. Recent developments in food regime theory, particularly the concept of an emerging third food regime (the so-called ‘corporate-environmental food regime’), provide a useful organizing framework for understanding recent agri-restructuring trends. We find that, while a globally based, third food regime is becoming more apparent, the attributes that relate to corporate retail-driven greening of the supply chain are less evident within Australia’s domestic market than in its EU counterparts. However, there is some evidence that Australia’s export market is subject to some degree of ‘greening at a distance’ due to private regulations imposed by supermarkets overseas. We argue that while broader agri-restructuring trends may be evident at an international level, elements of greening specific to national contexts are important for determining the trajectory of any third food regime.

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The safe working lifetime of a structure in a corrosive or other harsh environment is frequently not limited by the material itself but rather by the integrity of the coating material. Advanced surface coatings are usually crosslinked organic polymers such as epoxies and polyurethanes which must not shrink, crack or degrade when exposed to environmental extremes. While standard test methods for environmental durability of coatings have been devised, the tests are structured more towards determining the end of life rather than in anticipation of degradation. We have been developing prognostic tools to anticipate coating failure by using a fundamental understanding of their degradation behaviour which, depending on the polymer structure, is mediated through hydrolytic or oxidation processes. Fourier transform infrared spectroscopy (FTIR) is a widely-used laboratory technique for the analysis of polymer degradation and with the development of portable FTIR spectrometers, new opportunities have arisen to measure polymer degradation non-destructively in the field. For IR reflectance sampling, both diffuse (scattered) and specular (direct) reflections can occur. The complexity in these spectra has provided interesting opportunities to study surface chemical and physical changes during paint curing, service abrasion and weathering, but has often required the use of advanced statistical analysis methods such as chemometrics to discern these changes. Results from our studies using this and related techniques and the technical challenges that have arisen will be presented.

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Low speed rotating machines which are the most critical components in drive train of wind turbines are often menaced by several technical and environmental defects. These factors contribute to mount the economic requirement for Health Monitoring and Condition Monitoring of the systems. When a defect is happened in such system result in reduced energy loss rates from related process and due to it Condition Monitoring techniques that detecting energy loss are very difficult if not possible to use. However, in the case of Acoustic Emission (AE) technique this issue is partly overcome and is well suited for detecting very small energy release rates. Acoustic Emission (AE) as a technique is more than 50 years old and in this new technology the sounds associated with the failure of materials were detected. Acoustic wave is a non-stationary signal which can discover elastic stress waves in a failure component, capable of online monitoring, and is very sensitive to the fault diagnosis. In this paper the history and background of discovering and developing AE is discussed, different ages of developing AE which include Age of Enlightenment (1950-1967), Golden Age of AE (1967-1980), Period of Transition (1980-Present). In the next section the application of AE condition monitoring in machinery process and various systems that applied AE technique in their health monitoring is discussed. In the end an experimental result is proposed by QUT test rig which an outer race bearing fault was simulated to depict the sensitivity of AE for detecting incipient faults in low speed high frequency machine.

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Bagasse stockpile operations have the potential to lead to adverse environmental and social impacts. Dust releases can cause occupational health and safety concerns for factory workers and dust emissions impact on the surrounding community. Preliminary modelling showed that bagasse depithing would likely reduce the environmental risks, particularly dust emissions, associated with large-scale bagasse stockpiling operations. Dust emission properties were measured and used for dispersion modelling with favourable outcomes. Modelling showed a 70% reduction in peak ground level concentrations of PM10 dust (particles with an aerodynamic diameter less than 10 μm) from operations on depithed bagasse stockpiles compared to similar operations on stockpiles of whole bagasse. However, the costs of a depithing operation at a sugar factory were estimated to be approximately $2.1 million in capital expenditure to process 100 000 t/y of bagasse and operating costs were 200 000 p.a. The total capital cost for a 10 000 t/y operation was approximately $1.6 million. The cost of depithing based on a discounted cash flow analysis was $5.50 per tonne of bagasse for the 100 000 t/y scenario. This may make depithing prohibitively expensive in many situations if installed exclusively as a dust control measure.

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Environmental monitoring is becoming critical as human activity and climate change place greater pressures on biodiversity, leading to an increasing need for data to make informed decisions. Acoustic sensors can help collect data across large areas for extended periods making them attractive in environmental monitoring. However, managing and analysing large volumes of environmental acoustic data is a great challenge and is consequently hindering the effective utilization of the big dataset collected. This paper presents an overview of our current techniques for collecting, storing and analysing large volumes of acoustic data efficiently, accurately, and cost-effectively.

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This paper reviews a wide range of literature on environmental management in the field in Queensland, and analyzes this by period and by author. An episodic pattern of activities since European settlement is evident. Periods of exploration (pre-1950) and inventory- compilation (ca. 1950-1970) were followed by two decades of media and non-government organization campaigning (ca. 1970-1990), then an era dominated by government regulatory action (ca. 1990-2010). These eras dominated public perception of what was happening in environmental practice. They were delineated by historic ‘interventions’ (summarily, the end of World War II, the 1971 inflationary crisis, and computerization respectively).

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The growing public concern about the complexity, cost and uncertain efficacy of the statuary environmental impact assessment process applying to large-scale projects in Queensland is reviewed. This is based on field data gathered over the past six years sat large-scale marina developments that access major environmental reserves along the coast. An ecological design proposal to broaden the process consisted with both government aspirations and regional ecological parameters - termed Regional Landscape Strategies - would allow the existing Environmental Impact Asessment to be modified alone potentially more practicable and effective lines.

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Most existing marinas are boat parking/storing and servicing facilities that have been built over a long period of time for the convenience of local boat owners.

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M. fortuitum is a rapidly growing mycobacterium associated with community-acquired and nosocomial wound, soft tissue, and pulmonary infections. It has been postulated that water has been the source of infection especially in the hospital setting. The aim of this study was to determine if municipal water may be the source of community-acquired or nosocomial infections in the Brisbane area. Between 2007 and 2009, 20 strains of M. fortuitum were recovered from municipal water and 53 patients’ isolates were submitted to the reference laboratory. A wide variation in strain types was identified using repetitive element sequence-based PCR, with 13 clusters of ≥2 indistinguishable isolates, and 28 patterns consisting of individual isolates. The clusters could be grouped into seven similar groups (>95% similarity). Municipal water and clinical isolates collected during the same time period and from the same geographical area consisted of different strain types, making municipal water an unlikely source of sporadic human infection.