25 resultados para car-following models


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Motorbike riders are 34-times more likely to die in a crash compared to car drivers per km travelled (1). Such safety risks together with special skill requirements for the driver and much lower comfort compared to normal cars are the main reasons why motorbikes represent only a fraction of all vehicle sales in developed countries. Deakin University is developing a revolutionary cross-over fun vehicle with ultra low fuel consumption and emissions. This new vehicle generation combines the best of two worlds: the fun to drive, low cost, and small size of a scooter together with the safety, comfort and easiness to operate of a car. The result is a vehicle that is more fuel efficient than most cars or even scooters.

Various tilting cross over vehicles have been presented over the last decade that were trying to automate the tilting control of narrow vehicles to make them safer. Examples of these concepts are the Carver, Clever and in some way also the MP3 scooter from Piaggio. The problem with fully enclosed concepts like the Carver or Clever is that they require very complex and therefore also expensive tilting control systems so that the vehicles are not price competitive compared to low cost micro cars or even normal small cars. The MP3 on the other hand comes with a tilting control system which is only semi automatic so that typical car advantages - comprehensive safety features like crush zones, roll over protection, air bags, safety belts or comfort features like full weather protection including heating and cooling – can not be provided.

Deakin’s approach is quite different to the above mentioned concepts. The requirements were derived based on two different investigations: The first step was a critical evaluation of social trends and the second step was an in-depth benchmarking study of existing concepts which identified the typical strengths and weaknesses of these concepts. In a critical next step a new concept was created that addresses most of the weaknesses of existing tilting three-wheelers in a holistic approach by setting clear priority rankings for the vehicle targets, based on current trends. The priorities were set in the following order: Safety, Affordability, Fun and Efficiency (SAFE).

The key feature that enables an enclosed tilting vehicle is a fully automatic tilting control system. With an automatic tilting control system the driver does not need to put the feet on the ground to balance the vehicle when he stops, so the vehicle can be built with a full enclosure. This allows the implementation of typical car like safety features (seat belts, roll over structure, crush zones, air bags). The SafeRide™ tilting control system is a passive system that involves the driver’s balancing sense in its feedback control system. The vehicle has typical scooter like steering characteristics, where the steering is initiated through countersteering. Another safety critical design feature is the crush zone between the two front wheels which is not possible with only one front wheel or with the powertrain positioned between the front wheels, as the powertrain can’t absorb a lot of energy due to its structural stiffness and density. The passive tilting control system is quite simple and therefore makes the vehicle very affordable, an important factor for successful commercialisation.

Another advantage of integrating the human balancing senses in the feedback control of the tilting system is that the system kicks in slightly after the human balancing reacts. In some instances that can generate the typical adrenalin thrill known from riding a bike. This fun factor is quite common with many trend sports like mountain biking, surfing, roller-skating, snowboarding, or skateboarding. Some of these sports have seen very rapid growth only a short time after they have been invented. Utilising the human balancing system during driving also makes the vehicle safer as the adrenalin is produced after reaching a semi-stable driving condition that is controlled by the vehicles tilting control system, but before the vehicle reaches an unstable driving condition that can not be controlled by the vehicle but only (eventually) by the driver – if he has got the required driving skill and if he is alert enough.

Efficiency superior to most cars and scooters is achieved by the aerodynamics of a fully enclosed body structure in combination with the small frontal area of a typical scooter and the droplet shape enabled by the relatively wide front with 2 wheels and the very narrow tail with only one rear wheel. The passive tilting system also contributes to the extreme efficiency as the system only draws some small electrical power for the electronic control unit. Another feature is a low cost exhaust energy recovery system which is discussed in another paper.

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Previous research has suggested that individuals with OCD show compromised performance on tests assessing visuospatial and executive processes. This study aimed to further examine such findings by investigating the relationship between OCD symptom improvement following cognitive-behavioral therapy and changes in neuropsychological performance in individuals with OCD (n = 26), compared to test-retest control participants (n = 10). Successful treatment of OCD led to improvements relative to the control group on neuropsychological tasks measuring spatial working memory. Neuroscientific models of OCD consider such findings to be consistent with possible cortical dysfunction in OCD. However, a significant limitation of the study is in its inability to discount alternative explanations for this finding, such as the influence of changes in beliefs. Implications are discussed.

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Neurocomputational models of reaching indicate that efficient purposive correction of movement midflight (e.g., online control) depends on one's ability to generate and monitor an accurate internal (neural) movement representation. In the first study to test this empirically, the authors investigated the relationship between healthy young adults’ implicit motor imagery performance and their capacity to correct their reaching trajectory. As expected, after controlling for general reaching speed, hierarchical regression demonstrated that imagery ability was a significant predictor of hand correction speed; that is, faster and more accurate imagery performance associated with faster corrections to reaching following target displacement at movement onset. They argue that these findings provide preliminary support for the view that a link exists between an individual's ability to represent movement mentally and correct movement online efficiently.

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 Background
Provision of high quality transitional care is a challenge for health care providers in many western countries. This systematic review was conducted to (1) identify and synthesise research, using randomised control trial designs, on the quality of transitional care interventions compared with standard hospital discharge for older people with chronic illnesses, and (2) make recommendations for research and practice.

Methods

Eight databases were searched; CINAHL, Psychinfo, Medline, Proquest, Academic Search Complete, Masterfile Premier, SocIndex, Humanities and Social Sciences Collection, in addition to the Cochrane Collaboration, Joanna Briggs Institute and Google Scholar. Results were screened to identify peer reviewed journal articles reporting analysis of quality indicator outcomes in relation to a transitional care intervention involving discharge care in hospital and follow-up support in the home. Studies were limited to those published between January 1990 and May 2013. Study participants included people 60 years of age or older living in their own homes who were undergoing care transitions from hospital to home. Data relating to study characteristics and research findings were extracted from the included articles. Two reviewers independently assessed studies for risk of bias.

Results
Twelve articles met the inclusion criteria. Transitional care interventions reported in most studies reduced re-hospitalizations, with the exception of general practitioner and primary care nurse models. All 12 studies included outcome measures of re-hospitalization and length of stay indicating a quality focus on effectiveness, efficiency, and safety/risk. Patient satisfaction was assessed in six of the 12 studies and was mostly found to be high. Other outcomes reflecting person and family centred care were limited including those pertaining to the patient and carer experience, carer burden and support, and emotional support for older people and their carers. Limited outcome measures were reported reflecting timeliness, equity, efficiencies for community providers, and symptom management.

Conclusions
Gaps in the evidence base were apparent in the quality domains of timeliness, equity, efficiencies for community providers, effectiveness/symptom management, and domains of person and family centred care. Further research that involves the person and their family/caregiver in transitional care interventions is needed.

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Predictive frameworks for understanding and describing how animals respond to habitat fragmentation, particularly across edges, have been largely restricted to terrestrial systems. Abundances of zooplankton and meiofauna were measured across seagrasssand edges and the patterns compared with predictive models of edge effects. Artificial seagrass patches were placed on bare sand, and zooplankton and meiofauna were sampled with tube traps at five positions (from patch edges: 12, 60 and 130 cm into seagrass; and 12 and 60 cm onto sand). Position effects consisted of the following three general patterns: (1) increases in abundance around the seagrasssand edge (total abundance and cumaceans); (2) declining abundance from seagrass onto sand (calanoid copepods, harpacticoid copepods and amphipods); and (3) increasing abundance from seagrass onto sand (crustacean nauplii and bivalve larvae). The first two patterns are consistent with resource-distribution models, either as higher resources at the confluence of adjacent habitats or supplementation of resources from high-quality to low-quality habitat. The third pattern is consistent with reductions in zooplankton abundance as a consequence of predation or attenuation of currents by seagrass. The results show that predictive models of edge effects can apply to aquatic animals and that edges are important in structuring zooplankton and meiofauna assemblages in seagrass. © 2010 CSIRO.

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 Thermal comfort models, as we know them today, have been available since the early 1970’s and have been applied to assess the conditioning of our buildings. What we have is a comfort value of an interior environment at a particular location as a result of several measured parameters. What we don’t often consider is how the building contributes to this resulting thermal environment and how occupants respond to its possible changes. The following research considers the climatic and comfort findings from 15 fully air conditioned office buildings between Brisbane and Melbourne Australia during brief seasonal periods of measurement. Initially, each office building
was considered as its own individual project; however the grouping of the results has led to some interesting observations:
Regardless of building type or whether there is a narrow controlled comfort band,
there can be a significant variation in the clothing level of occupants.
There is a greater exterior to interior air temperature correlation than might be expected among fully air-conditioned buildings. The diurnal ranges of interior temperatures (over 24 hours) may be far greater than anticipated. It is realised that fully conditioned buildings are far more variable than perhaps realised and that occupant comfort may relate more to user interaction (CLO value), building construction type (weight) and envelope air tightness. As a result, this investigation raises perhaps more questions than answers as to how we assess thermal comfort in
buildings.

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ABSTRACT
Objectives: To assess whether following standardisation of tobacco packaging in Australia, smokers were, as predicted by the tobacco industry, more likely to use illicit tobacco.
Methods: National cross-sectional telephone surveys conducted continuously from April 2012 (6 months before implementation of plain packaging (PP)) to March 2014 (15 months after) using responses from current cigarette smokers (n=8679). Changes between pre-PP, the transition to PP and PP phase were examined using logistic regression models.
Results: Among those whose factory-made cigarettes were purchased in Australia, compared with pre-PP, there were no significant increases in the PP phase in use of: ‘cheap whites’ (<0.1%; OR=0.24, 95% CI 0.04 to 1.56, p=0.134); international brands purchased for 20% or more below the recommended retail price (0.2%; OR=3.49, 95% CI 0.66 to 18.35, p=0.140); or packs purchased from informal sellers (<0.1%; OR=0.24, 95% CI 0.04 to 1.47, p=0.124). The prevalence of any use of unbranded illicit tobacco remained at about 3% (adjusted OR=0.79, 95% CI 0.58 to 1.08, p=0.141).
Conclusions: While unable to quantify the total extent of use of illicit manufactured cigarettes, in this large national survey we found no evidence in Australia of increased use of two categories of manufactured cigarettes likely to be contraband, no increase in purchase from informal sellers and no increased use of unbranded illicit ‘chop-chop’ tobacco.

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BACKGROUND: Acquisition of a disability in adulthood has been associated with a reduction in mental health. We tested the hypothesis that low wealth prior to disability acquisition is associated with a greater deterioration in mental health than for people with high wealth. METHODS: We assess whether level of wealth prior to disability acquisition modifies this association using 12 waves of data (2001-2012) from the Household, Income and Labour Dynamics in Australia survey-a population-based cohort study of working-age Australians. Eligible participants reported at least two consecutive waves of disability preceded by at least two consecutive waves without disability (1977 participants, 13,518 observations). Fixed-effects linear regression was conducted with a product term between wealth prior to disability (in tertiles) and disability acquisition with the mental health component score of the SF-36 as the outcome. RESULTS: In models adjusted for time-varying confounders, there was evidence of negative effect measure modification by prior wealth of the association between disability acquisition and mental health (interaction term for lowest wealth tertile: -2.2 points, 95% CI -3.1 points, -1.2, p<0.001); low wealth was associated with a greater decline in mental health following disability acquisition (-3.3 points, 95% CI -4.0, -2.5) than high wealth (-1.1 points, 95% CI -1.7, -0.5). CONCLUSION: The findings suggest that low wealth prior to disability acquisition in adulthood results in a greater deterioration in mental health than among those with high wealth.

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Acquiring a disability in adulthood is associated with a reduction in mental health and access to secure and affordable housing is associated with better mental health. We hypothesised that the association between acquisition of disability and mental health is modified by housing tenure and affordability. We used twelve annual waves of data (2001-2012) (1913 participants, 13,037 observations) from the Household, Income and Labour Dynamics in Australia survey. Eligible participants reported at least two consecutive waves of disability preceded by two consecutive waves without disability. Effect measure modification, on the additive scale, was tested in three fixed-effects linear regression models (which remove time-invariant confounding) which included a cross-product term between disability and prior housing circumstances: housing tenure by disability; housing affordability by disability and, in a sub-sample (896 participants 5913 observations) with housing costs, tenure/affordability by disability. The outcome was the continuous mental component summary (MCS) of SF-36. Models adjusted for time-varying confounders. There was statistical evidence that prior housing modified the effect of disability acquisition on mental health. Our findings suggested that those in affordable housing had a -1.7 point deterioration in MCS (95% CI -2.1, -1.3) following disability acquisition and those in unaffordable housing had a -4.2 point reduction (95% CI -5.2, -1.4). Among people with housing costs, the largest declines in MCS were for people with unaffordable mortgages (-5.3, 95% CI -8.8, -1.9) and private renters in unaffordable housing (-4.0, 95% CI -6.3, -1.6), compared to a -1.4 reduction (95% CI -2.1, -0.7) for mortgagors in affordable housing. In sum, we used causally-robust fixed-effects regression and showed that deterioration in mental health following disability acquisition is modified by prior housing circumstance with the largest negative associations found for those in unaffordable housing. Future research should test whether providing secure, affordable housing when people acquire a disability prevents deterioration in mental health.

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Reforestation of agricultural land with mixed-species environmental plantings (native trees and shrubs) can contribute to mitigation of climate change through sequestration of carbon. Although soil carbon sequestration following reforestation has been investigated at site- and regional-scales, there are few studies across regions where the impact of a broad range of site conditions and management practices can be assessed. We collated new and existing data on soil organic carbon (SOC, 0-30 cm depth, N = 117 sites) and litter (N = 106 sites) under mixed-species plantings and an agricultural pair or baseline across southern and eastern Australia. Sites covered a range of previous land uses, initial SOC stocks, climatic conditions and management types. Differences in total SOC stocks following reforestation were significant at 52% of sites, with a mean rate of increase of 0.57 ± 0.06 Mg C ha-1 y-1. Increases were largely in the particulate fraction, which increased significantly at 46% of sites compared with increases at 27% of sites for the humus fraction. Although relative increase was highest in the particulate fraction, the humus fraction was the largest proportion of total SOC and so absolute differences in both fractions were similar. Accumulation rates of carbon in litter were 0.39 ± 0.02 Mg C ha-1 y-1, increasing the total (soil + litter) annual rate of carbon sequestration by 68%. Previously-cropped sites accumulated more SOC than previously-grazed sites. The explained variance differed widely among empirical models of differences in SOC stocks following reforestation according to SOC fraction and depth for previously-grazed (R2 = 0.18-0.51) and previously-cropped (R2 = 0.14-0.60) sites. For previously-grazed sites, differences in SOC following reforestation were negatively related to total SOC in the pasture. By comparison, for previously-cropped sites, differences in SOC were positively related to mean annual rainfall. This improved broad-scale understanding of the magnitude and predictors of changes in stocks of soil and litter C following reforestation is valuable for the development of policy on carbon markets and the establishment of future mixed-species environmental plantings.