160 resultados para tunnel reinforcement
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Particle number concentrations vary significantly with environment and, in this study, we attempt to assess the significance of these differences. Towards this aim, we reviewed 85 papers that have reported particle number concentrations levels at 126 sites covering different environments. We grouped the results into eight categories according to measurement location including: road tunnel, on-road, road-side, street canyon, urban, urban background, rural, and clean background. From these reports, the overall median number concentration for each of the eight site categories was calculated. The eight location categories may be classified into four distinct groups. The mean median particle number locations for these four types were found to be statistically different from each other. Rural and clean background sites had the lowest concentrations of about 3x103 cm-3. Urban and urban background sites showed concentrations that were three times higher (9x103 cm-3). The mean concentration for the street canyon, roadside and on-road measurement sites was 4.6x104 cm-3, while the highest concentrations were observed in the road tunnels (8.6x104 cm-3). This variation is important when assessing human exposure-response for which there is very little data available, making it difficult to develop health guidelines, a basis for national regulations. Our analyses shows that the current levels in environments affected by vehicle emissions are 3 to 28 times higher than in the natural environments. At present, there is no threshold level in response to exposure to ultrafine particles. Therefore, future control and management strategies should target a decrease of these particles in urban environments by more than one order of magnitude to bring them down to the natural background. At present there is a long way to go to achieve this.
Resumo:
Particle number concentrations vary significantly with environment and, in this study, we attempt to assess the significance of these differences. Towards this aim, we reviewed 85 papers that have reported particle number concentrations levels at 126 sites covering different environments. We grouped the results into eight categories according to measurement location including: road tunnel, on-road, road-side, street canyon, urban, urban background, rural, and clean background. Median values were calculated for each category. This review was restricted to papers that presented concentrations numerically. The majority of the reports were based on either CPC or SMPS measurements, with a limited number of papers reporting results from both instruments at the same site. Hence there were several overlaps between the number of CPC and SMPS measuring sites. Most of the studies reported multiple measurements at a given study site, while some studies included results from more than one site. From these reports, the overall median value for each location category was calculated...
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Child sexual abuse is a serious problem that has received increased attention in recent years. From an ecological perspective, in which social problems are viewed in the context of characteristics of individuals, families, and broader societal systems (Prilleltensky, Peirson, & Nelson, 2001), preventing child sexual abuse involves strengthening capacity to intervene at individual, family/relationship, school, and community levels. School-based education programs have been developed in efforts to prevent child sexual abuse before it happens and to provide children who may already be experiencing it with help seeking information. Use of these programs must be based on evidence rather than ideology. Evaluations of these programs have demonstrated that sexual abuse prevention education can provide children with improved knowledge and skills for responding to and reporting potential sexual abuse. However, this learning does not seem to be maintained over time which means further attention should be given to repeated learning, opportunities for concept reinforcement and integration with other topics. School-based programs typically present information to children by presenting a series of core concepts and messages which are delivered using engaging pedagogical strategies such as multi-media technologies, animations, theatre and songs, puppets, picture books, and games. This chapter will outline the key characteristics of effective child sexual abuse prevention programs, and will provide directions for future research and practice.
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Large number of rooftop Photovoltaics (PVs) have turned traditional passive networks into active networks with intermittent and bidirectional power flow. A community based distribution network grid reinforcement process is proposed to address technical challenges associated with large integration of rooftop PVs. Probabilistic estimation of intermittent PV generation is considered. Depending on the network parameters such as the R/X ratio of distribution feeder, either reactive control from PVs or coordinated control of PVs and Battery Energy Storage (BES) has been proposed. Determination of BES capacity is one of the significant outcomes from the proposed method and several factors such as variation in PV installed capacity as well as participation from community members are analyzed. The proposed approach is convenient for the community members providing them flexibility of managing their integrated PV and BES systems
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Swietenia macrophylla King (Meliaceae: Swietenioideae) provides one of the premier timbers of the world. The mahogany shoot borer Hypsipyla robusta Moore (Lepidoptera: Pyralidae) is an economically important pest of S. macrophylla throughout Asia, Africa and the Pacific. No viable method of controlling this pest is known. Previous observations have suggested that the presence of overhead shade may reduce attack by H. robusta, but this has not been investigated experimentally. This research was therefore designed to assess the influence of light availability on shoot-borer attack on S. macrophylla, by establishing seedlings under three different artificial shade regimes, then using these seedlings to test oviposition preference of adult moths, neonate larval survival and growth and development of shoot borer larvae. Oviposition preference of shoot borer moths was tested on leaves from seedlings grown under artificial shade for 63 weeks. A significant difference in choice was recorded between treatments, with 27.4 ± 1.5 eggs laid under high shade and 87.1 ± 1.8 under low shade. Neonate larval survival on early flushing leaflets of S. macrophylla did not differ significantly between shade treatments. Larval growth rate, estimated by measuring daily frass width, was significantly higher for those larvae fed on seedlings from the high and medium shade treatments (0.1 mm/day), than the low shade treatment (0.06 mm/day). In laboratory-reared larvae, the total mass of frass produced was significantly higher in the high shade treatment (0.4 g) than under the low shade treatment (0.2 g). Longer tunnel lengths were bored by larvae in plants grown under high shade (12.0 ± 2.4 cm) than under low shade (7.07 ± 1.9 cm). However, pupal mass under low shade was 48% higher than that under the high shade treatment, suggesting that plants grown under high shade were of lower nutritional quality for shoot borer larvae. These results indicate that shading of mahogany seedlings may reduce the incidence of shoot borer attack, by influencing both oviposition and larval development. The establishment of mahogany under suitable shade regimes may therefore provide a basis for controlling shoot borer attack using silvicultural approaches.
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A travel article about touring in New Zealand. ‘What’s the best thing about England?’ asked the Englishman next to me, quite suddenly, as we came out of a tunnel. ‘Well?’ I didn’t know. ‘Answer,’ he said, ‘is France.’ Here was the thing. My companion was a tennis pro, and these days he divided his time between London and Paris. Because you could. ‘Nothing big, which suits me: I am only moderately successful. Mainly rich ladies, if you know what I mean. Much prefer the French side, if you know what I mean.’ I think I knew what he meant...
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Self-care management is needed for effective management of chronic kidney disease. The main aim for treatment or management of chronic kidney disease is to delay the worsening of kidney function, and to prevent or to manage the co-morbidities. Selfcare management is not easy, and patients will face many challenges, especially when they cannot get use to the new treatment plan. One of the challenges they face is dietary restriction, which is a very important aspect in any self-care management programme. Chronic kidney disease patients require a low-protein, low-sodium, low-potassium, and low-phosphorus diet. There are several strategies patients can undertake to ensure adherence, such as self-monitoring their dietary habits and type of food consumed using a food diary; involving social support, such as family members and spouse to help them to adhere to their diet restrictions; setting goals and providing positive reinforcement when they achieved the targeted goals; joining self-management programmes to equip themselves with the necessary skills so that they can better adhere to the treatment regimes, including diet restriction; and lastly, having the knowledge about their regime, and using this knowledge to help them understand and improve their adherence.
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This thesis examined the extent to which individual differences, as conceptualised by the revised Reinforcement Sensitivity Theory, influenced young drivers' information processing and subsequent acceptance of anti-speeding messages. Using a multi-method approach, the findings highlighted the utility of combining objective measures (a cognitive response time task and electroencephalography) with self-report measures to assess message processing and message acceptance, respectively. This body of research indicated that responses to anti-speeding messages may differ depending on an individual's personality disposition. Overall, the research provided further insight into the development of message strategies to target high risk drivers.
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Young novice drivers are at considerable risk of injury on the road. Their behaviour appears vulnerable to the social influence of their parents and friends. The nature and mechanisms of parent and peer influence on young novice driver (16–25 years) behaviour was explored via small group interviews (n = 21) and two surveys (n1 = 1170, n2 = 390) to inform more effective young driver countermeasures. Parental and peer influence occurred in preLicence, Learner, and Provisional (intermediate) periods. Pre-Licence and unsupervised Learner drivers reported their parents were less likely to punish risky driving (e.g., speeding). These drivers were more likely to imitate their parents and reported their parents were also risky drivers. Young novice drivers who experienced or expected social punishments from peers, including ‘being told off’ for risky driving, reported less riskiness. Conversely drivers who experienced or expected social rewards such as being ‘cheered on’ by friends – who were also more risky drivers – reported more risky driving including crashes and offences. Interventions enhancing positive influence and curtailing negative influence may improve road safety outcomes not only for young novice drivers, but for all persons who share the road with them. Parent-specific interventions warrant further development and evaluation including: modelling safe driving behaviour by parents; active monitoring of driving during novice licensure; and sharing the family vehicle during the intermediate phase. Peer-targeted interventions including modelling of safe driving behaviour and attitudes; minimisation of social reinforcement and promotion of social sanctions for risky driving also need further development and evaluation.
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Increasing threat of terrorism highlights the importance of enhancing the resilience of underground tunnels to all hazards. This paper develops, applies and compares the Arbitrary Lagrangian Eulerian (ALE) and Smooth Particle Hydrodynamics (SPH) techniques to treat the response of buried tunnels to surface explosions. The results and outcomes of the two techniques were compared, along with results from existing test data. The comparison shows that the ALE technique is a better method for describing the tunnel response for above ground explosion with regards to modeling accuracy and computational efficiency. The ALE technique was then applied to treat the blast response of different types of segmented bored tunnels buried in dry sand. Results indicate that the most used modern ring type segmented tunnels were more flexible for in-plane response, however, they suffered permanent drifts between the rings. Hexagonal segmented tunnels responded with negligible drifts in the longitudinal direction, but the magnitudes of in-plane drifts were large and hence hazardous for the tunnel. Interlocking segmented tunnels suffered from permanent drifts in both the longitudinal and transverse directions. Multi-surface radial joints in both the hexagonal and interlocking segments affected the flexibility of the tunnel in the transverse direction. The findings offer significant new information in the behavior of segmented bored tunnels to guide their future implementation in civil engineering applications.
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Movement of malaria across international borders poses a major obstacle to achieving malaria elimination in the 34 countries that have committed to this goal. In border areas, malaria prevalence is often higher than in other areas due to lower access to health services, treatment-seeking behaviour of marginalised populations that typically inhabit border areas, difficulties in deploying prevention programs to hard-to-reach communities, often in difficult terrain, and constant movement of people across porous national boundaries. Malaria elimination in border areas will be challenging, and key to addressing the challenges is strengthening of surveillance activities for rapid identification of any importation or reintroduction of malaria. This could involve taking advantage of technological advances, such as spatial decision support systems, which can be deployed to assist program managers to carry out preventive and reactive measures, and mobile phone technology, which can be used to capture the movement of people in the border areas and likely sources of malaria importation. Additionally, joint collaboration in the prevention and control of cross-border malaria by neighbouring countries, and reinforcement of early diagnosis and prompt treatment are ways forward in addressing the problem of cross-border malaria.
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Monte-Carlo Tree Search (MCTS) is a heuristic to search in large trees. We apply it to argumentative puzzles where MCTS pursues the best argumentation with respect to a set of arguments to be argued. To make our ideas as widely applicable as possible, we integrate MCTS to an abstract setting for argumentation where the content of arguments is left unspecified. Experimental results show the pertinence of this integration for learning argumentations by comparing it with a basic reinforcement learning.
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"It could easily provide the back-drop for a James Bond movie. Deep inside a mountain near the North Pole, down a fortified tunnel, and behind airlocked doors in a vault frozen to -18 degrees Celsius, scientists are squirreling away millions of seed samples. The samples constitute the very foundation of agriculture, the biological diversity needed so the world's major food crops can adapt to the next pest or disease, or to climate change. It's little wonder that the Svalbard Global Seed Vault has captured the public's imagination more than almost any agricultural topic in recent years. Popular press reports about the ‘Doomsday Vault,’ however, typically mask the complexity of the endeavor and, if anything, underestimate its practical utility." Cary Fowler This chapter considers the use of seed banks to address concerns about intellectual property, climate change and food security. It has a number of themes. First of all, it is interested in the use of ‘Big Science’ projects to address pressing global scientific concerns and Millennium Development Goals. Second, it highlights the increasing use of banks as a means of managing both property and intellectual property across a wide range of fields of agriculture and biotechnology. Third, it considers the linkage of intellectual property, access to genetic resources and benefit sharing. There are a variety of positions in this debate. Some see requirements in respect of access to genetic resources and benefit sharing as an inconvenient burden for science and commerce. Others defend access to genetic resources and benefit sharing as meaningful and productive. Those inclined to somewhat more conspiratorial views suggest that access to genetic resources and benefit sharing are a ruse to facilitate biopiracy. This chapter has a number of components. Section I focuses upon the Consultative Group on International Agricultural Research (CGIAR) network – often raised as a model for Climate Innovation Centres. Section II considers the Svalbard Global Seed Vault – the so-called Doomsday Vault. After a consideration of the World Summit on Food Security in 2009, it is concluded in this chapter that any future international agreement on climate change needs to address intellectual property, plant genetic resources and food security.
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Partially grouted masonry walls subjected to in-plane shear exhibit a complex behaviour because of the influence of the aspect ratio, the pre-compression, the grouting pattern, the ratios of the horizontal and the vertical reinforcements, the boundary conditions and the characteristics of the constituent materials. The existing in-plane shear expressions for the partially grouted masonry are formulated as sum of strength of three parameters, namely, the masonry, the reinforcement and the axial force. The parameter ‘masonry’ includes the wall aspect ratio and the masonry compressive strength; the aspect ratio of the unreinforced panel inscribed into the grouted cores and bond beams are not considered, although failure is often dominated by these unreinforced masonry panels. This paper describes the dominance of these panels, particularly those that are squat, to the shear capacity of whole of shear walls. Further, the current design formulae are shown highly un-conservative by many researchers; this paper provides a potential reason for this un-conservativeness. It is shown that by including an additional term of the unreinforced panel aspect ratio a rational design formula could be established. This new expression is validated with independent test results reported in the literature – both Australian and overseas; the predictions are shown to be conservative.