845 resultados para 090205 Hybrid Vehicles and Powertrains
Resumo:
The Vehicle-to-Grid (V2G) concept is based on the newly developed and marketed technologies of hybrid petrol-electric vehicles, most notably represented by the Toyota Prius, in combination with significant structural changes to the world's energy economy, and the growing strain on electricity networks. The work described in this presentation focuses on the market and economic impacts of grid connected vehicles. We investigate price reduction effects and transmission system expansion cost reduction. We modelled a large numbers of plug-in-hybrid vehicle batteries by aggregating them into a virtual pumped-storage power station at the Australian national electricity market's (NEM) region level. The virtual power station concept models a centralised control for dispatching (operating) the aggregated electricity supply/demand capabilities of a large number of vehicles and their batteries. The actual level of output could be controlled by human or automated agents to either charge or discharge from/into the power grid. As previously mentioned the impacts of widespread deployments of this technology are likely to be economic, environmental and physical.
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Collaborative infrastructure projects use hybrid formal and informal governance structures to manage transactions. Based on previous desk-top research, the authors identified the key mechanisms underlying project governance, and posited the performance implications of the governance (Chen et al. 2012). The current paper extends that qualitative research by testing the veracity of those findings using data from 320 Australian construction organisations. The results provide, for the first time, reliable and valid scales to measure governance and performance of collaborative projects, and the relationship between them. The results confirm seven of seven hypothesised governance mechanisms; 30 of 43 hypothesised underlying actions; eight of eight hypothesised key performance indicators; and the dual importance of formal and informal governance. A startling finding of the study was that the implementation intensity of informal mechanisms (non-contractual conditions) is a greater predictor of project performance variance than that of formal mechanisms (contractual conditions). Further, contractual conditions do not directly impact project performance; instead their impact is mediated by the non-contractual features of a project. Obligations established under the contract are not sufficient to optimise project performance.
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Studies of semantic impairment arising from brain disease suggest that the anterior temporal lobes are critical for semantic abilities in humans; yet activation of these regions is rarely reported in functional imaging studies of healthy controls performing semantic tasks. Here, we combined neuropsychological and PET functional imaging data to show that when healthy subjects identify concepts at a specific level, the regions activated correspond to the site of maximal atrophy in patients with relatively pure semantic impairment. The stimuli were color photographs of common animals or vehicles, and the task was category verification at specific (e.g., robin), intermediate (e.g., bird), or general (e.g., animal) levels. Specific, relative to general, categorization activated the antero-lateral temporal cortices bilaterally, despite matching of these experimental conditions for difficulty. Critically, in patients with atrophy in precisely these areas, the most pronounced deficit was in the retrieval of specific semantic information.
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A Three-Phase Nine-Switch Converter (NSC) topology for Doubly Fed Induction Generator in wind energy generation is proposed in this paper. This converter topology was used in various applications such as Hybrid Electric Vehicles and Uninterruptable Power Supplies. In this paper, Nine-Switch Converter is introduced in Doubly Fed Induction Generator in renewable energy application for the first time. It replaces the conventional Back-to-Back Pulse Width Modulated voltage source converter (VSC) which composed of twelve switches in many DFIG applications. Reduction in number of switches is the most beneficial in terms of cost and power switching losses. The operation principle of Nine-Switch Converter using SPWM method is discussed. The resulting NSC performance of rotor side current control, active power and reactive control are compared with Back-to Back voltage source converter performance. DC link voltage regulation using front end converter is also presented. Finally the simulation results of DFIG performances using NSC and Back-to-Back VSC are analyzed and compared.
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This study investigates potential demand for infrastructure investment for alternative fuel vehicles by applying stated preference methods to a Japanese sample. The potential demand is estimated on the basis of how much people are willing to pay for alternative fuel vehicles under various refueling scenarios. Using the estimated parameters, the economic efficiency of establishing battery-exchange stations for electric vehicles is examined. The results indicate that infrastructural development of battery-exchange stations can be efficient when electric vehicle sales exceed 5.63% of all new vehicle sales. Further, we find a complementary relationship between the cruising ranges of alternative fuel vehicles and the infrastructure established.
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Picture books are known and familiar objects to many children and adults. They have been variously described as art objects, cultural documents, hybrid texts and verbal-visual art forms. They have also been variously categorised according to their readership – ranging from very young children to older readers, the latter can extend through the primary years to high school and even into adulthood. Scholars and students study picture books as part of an evolving literary and cultural landscape which has given rise to new genres and trends, such as ‘multicultural picture books’, ‘environmental picture books’ and ‘postmodern picture books’, and what Cherie Allan terms, ‘postmodernesque picture books’, that is, ‘picturebooks about postmodernity’ (Allan, 2012, p. 141). Picture books are also the staple literature in many early years and primary school classrooms for literacy and literary development, thus supporting the designated strands for literacy, literature, and language in the Australian Curriculum: English.
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Purpose To quantify the effects of driver age on night-time pedestrian conspicuity, and to determine whether individual differences in visual performance can predict drivers' ability to recognise pedestrians at night. Methods Participants were 32 visually normal drivers (20 younger: M = 24.4 years ± 6.4 years; 12 older: M = 72.0 years ± 5.0 years). Visual performance was measured in a laboratory-based testing session including visual acuity, contrast sensitivity, motion sensitivity and the useful field of view. Night-time pedestrian recognition distances were recorded while participants drove an instrumented vehicle along a closed road course at night; to increase the workload of drivers, auditory and visual distracter tasks were presented for some of the laps. Pedestrians walked in place, sideways to the oncoming vehicles, and wore either a standard high visibility reflective vest or reflective tape positioned on the movable joints (biological motion). Results Driver age and pedestrian clothing significantly (p < 0.05) affected the distance at which the drivers first responded to the pedestrians. Older drivers recognised pedestrians at approximately half the distance of the younger drivers and pedestrians were recognised more often and at longer distances when they wore a biological motion reflective clothing configuration than when they wore a reflective vest. Motion sensitivity was an independent predictor of pedestrian recognition distance, even when controlling for driver age. Conclusions The night-time pedestrian recognition capacity of older drivers was significantly worse than that of younger drivers. The distance at which drivers first recognised pedestrians at night was best predicted by a test of motion sensitivity.
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Roundabouts reduce the frequency and severity of motor vehicle crashes and therefore the number installed has increased dramatically in the last 20 years in many countries. However, the safety impacts of roundabouts for bicycle riders are a source of concern, with many studies reporting lower injury reductions for cyclists than car occupants. This paper summarises the results of a project undertaken to provide guidance on how cyclist safety could be improved at existing roundabouts in Queensland, Australia, where cyclist crashes have been increasing and legislation gives motor vehicles priority over cyclists and pedestrians at roundabouts. The review of international roundabout design guidelines identified two schools of design: tangential roundabouts (common in English-speaking countries, including Australia), which focus on minimising delay to motor vehicles, and radial roundabouts (common in continental Europe), which focus on speed reduction and safety. While it might be expected that radial roundabouts would be safer for cyclists, there have been no studies to confirm this view. Most guidelines expect cyclists to act as vehicle traffic in single-lane, typically low-speed, roundabouts. Some jurisdictions do not permit cyclists to travel on multi-lane roundabouts, and recommend segregated bicycle facilities because of their lowest crash risk for cyclists. Given that most bicycle-vehicle crashes at roundabouts involve an entering vehicle and a circulating cyclist, the greatest challenges appear to be reducing the speed of motor vehicles on the approach/entry to roundabouts and other ways of maximizing the likelihood that cyclists will be seen. Lower entry speeds are likely to underpin the greater safety of compact roundabouts for cyclists and, conversely, the higher than expected crash rates at two-lane roundabouts. European research discourages the use of bike lanes in roundabouts which position cyclists at the edge of the road and contributes to cyclists being less likely to be noticed by drivers.
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This paper reviews the state-of-the-art in the automation of underground mining vehicles and reports on the development of an autonomous navigation system under development through the CMTE with sponsorship arranged by AMIRA. Past attempts at automating LHDs and haul trucks are described and their particular strengths and weaknesses are discussed. The auto-guidance system being developed overcomes some of the limitations of state-of-the-art prototype æcommercialÆ systems. It can be retrofitted to existing remote controlled vehicles, uses minimum installed infrastructure and is flexible enough for rapid relocation to alternate routes. The navigation techniques use data fusion of two separate sets of sensors combining natural feature recognition, nodal maps and inertial navigation techniques. Collision detection is incorporated and people and other traffic are excluded from the tramming area. This paper describes the work being done by the group with regard to auto-tramming and also outlines the future goals.
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Vehicle registration represents an important component of the management of the road transport system in Queensland, with most vehicles required to be registered before they can be driven or parked on a public road (Department of Transport and Main Roads, 2010b). In addition to the collection of taxes for road construction and maintenance, the current registration system also: • Sets the safety standards required for vehicles to be allowed on public roads; • Allows driver behaviour to be managed by identifying vehicles, and the responsible owners of vehicles, for enforcement purposes; and • Facilitates the collection of insurance premiums for the Queensland Compulsory Third Party (CTP) insurance scheme.
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There is a current lack of understanding regarding the use of unregistered vehicles on public roads and road-related areas, and the links between the driving of unregistered vehicles and a range of dangerous driving behaviours. This report documents the findings of data analysis conducted to investigate the links between unlicensed driving and the driving of unregistered vehicles, and is an important initial undertaking into understanding these behaviours. This report examines de-identified data from two sources: crash data; and offence data. The data was extracted from the Queensland Department of Transport and Main Roads (TMR) databases and covered the period from 2003 to 2008.
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Through ubiquitous computing and location-based social media, information is spreading outside the traditional domains of home and work into the urban environment. Digital technologies have changed the way people relate to the urban form supporting discussion on multiple levels, allowing more citizens to be heard in new ways (Fredericks et al. 2013; Houghton et al. 2014; Caldwell et al. 2013). Face-to-face and digitally mediated discussions, facilitated by tangible and hybrid interaction, such as multi-touch screens and media façades, are initiated through a telephone booth inspired portable structure: The InstaBooth. The InstaBooth prototype employs a multidisciplinary approach to engage local communities in a situated debate on the future of their urban environment. With it, we capture citizens’ past stories and opinions on the use and design of public places. The way public consultations are currently done often engages only a section of the population involved in a proposed development; the more vocal citizens are not necessarily the more representative of the communities (Jenkins 2006). Alternative ways to engage urban dwellers in the debate about the built environment are explored at the moment, including the use of social media or online tools (Foth 2009). This project fosters innovation by providing pathways for communities to participate in the decision making process that informs the urban form. The InstaBooth promotes dialogue and mediation between a bottom-up and a top-down approach to urban design, with the aim of promoting community connectedness with the urban environment. The InstaBooth provides an engagement and discussion platform that leverages a number of locally developed display and interaction technologies in order to facilitate a dialogue of ideas and commentary. The InstaBooth combines multiple interaction techniques into a hybrid (digital and analogue) media space. Through the InstaBooth, urban design and architectural proposals are displayed encouraging commentary from visitors. Inside the InstaBooth, visitors can activate a multi-touch screen in order to browse media, write a note, or draw a picture to provide feedback. The purpose of the InstaBooth is to engage with a broader section of society, including those who are often marginalised. The specific design of the internal and external interfaces, the mutual relationship between these interfaces with regards to information display and interaction, and the question how visitors can engage with the system, are part of the research agenda of the project.
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Graphitic like layered materials exhibit intriguing electronic structures and thus the search for new types of two-dimensional (2D) monolayer materials is of great interest for developing novel nano-devices. By using density functional theory (DFT) method, here we for the first time investigate the structure, stability, electronic and optical properties of monolayer lead iodide (PbI2). The stability of PbI2 monolayer is first confirmed by phonon dispersion calculation. Compared to the calculation using generalized gradient approximation, screened hybrid functional and spin–orbit coupling effects can not only predicts an accurate bandgap (2.63 eV), but also the correct position of valence and conduction band edges. The biaxial strain can tune its bandgap size in a wide range from 1 eV to 3 eV, which can be understood by the strain induced uniformly change of electric field between Pb and I atomic layer. The calculated imaginary part of the dielectric function of 2D graphene/PbI2 van der Waals type hetero-structure shows significant red shift of absorption edge compared to that of a pure monolayer PbI2. Our findings highlight a new interesting 2D material with potential applications in nanoelectronics and optoelectronics.
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The invasive fruit fly, Bactrocera invadens Drew, Tsuruta & White, is a highly polyphagous fruit pest that occurs predominantly in Africa yet has its origins in the Indian subcontinent. It is extremely morphologically and genetically similar to the Oriental fruit fly, Bactrocera dorsalis (Hendel); as such the specific relationship between these two species is unresolved. We assessed prezygotic compatibility between B. dorsalis and B. invadens using standardized field cage mating tests, which have proven effectiveness in tephritid cryptic species studies. These tests were followed by an assessment of postzygotic compatibility by examining egg viability, larval and pupal survival, and sex ratios of offspring produced from parental and subsequent F1 crosses to examine for hybrid breakdown as predicted under a two-species hypothesis. B. dorsalis was sourced from two countries (Pakistan and China), and each population was compared with B. invadens from its type locality of Kenya. B. invadens mated randomly with B. dorsalis from both localities, and there were generally high levels of hybrid viability and survival resulting from parental and F1 crosses. Furthermore, all but one hybrid cross resulted in equal sex ratios, with the single deviation in favor of males and contrary to expectations under Haldane's rule. These data support the hypothesis that B. dorsalis and B. invadens represent the same biological species, an outcome that poses significant implications for pest management and international trade for sub-Saharan Africa.
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Stability analyses have been widely used to better understand the mechanism of traffic jam formation. In this paper, we consider the impact of cooperative systems (a.k.a. connected vehicles) on traffic dynamics and, more precisely, on flow stability. Cooperative systems are emerging technologies enabling communication between vehicles and/or with the infrastructure. In a distributed communication framework, equipped vehicles are able to send and receive information to/from other equipped vehicles. Here, the effects of cooperative traffic are modeled through a general bilateral multianticipative car-following law that improves cooperative drivers' perception of their surrounding traffic conditions within a given communication range. Linear stability analyses are performed for a broad class of car-following models. They point out different stability conditions in both multianticipative and nonmultianticipative situations. To better understand what happens in unstable conditions, information on the shock wave structure is studied in the weakly nonlinear regime by the mean of the reductive perturbation method. The shock wave equation is obtained for generic car-following models by deriving the Korteweg de Vries equations. We then derive traffic-state-dependent conditions for the sign of the solitary wave (soliton) amplitude. This analytical result is verified through simulations. Simulation results confirm the validity of the speed estimate. The variation of the soliton amplitude as a function of the communication range is provided. The performed linear and weakly nonlinear analyses help justify the potential benefits of vehicle-integrated communication systems and provide new insights supporting the future implementation of cooperative systems.