49 resultados para Passenger pigeon.


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There is a growing body of data on avian eyes, including measurements of visual pigment and oil droplet spectral absorption, and of receptor densities and their distributions across the retina. These data are sufficient to predict psychophysical colour discrimination thresholds for light-adapted eyes, and hence provide a basis for relating eye design to visual needs. We examine the advantages of coloured oil droplets, UV vision and tetrachromacy for discriminating a diverse set of avian plumage spectra under natural illumination. Discriminability is enhanced both by tetrachromacy and coloured oil droplets. Oil droplets may also improve colour constancy. Comparison of the performance of a pigeon's eye, where the shortest wavelength receptor peak is at 410 nm, with that of the passerine Leiothrix, where the ultraviolet-sensitive peak is at 365 nm, generally shows a small advantage to the latter, but this advantage depends critically on the noise level in the sensitivity mechanism and on the set of spectra being viewed.

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There are two significant issues facing road transport in the medium to long term: the depletion of cheap oil reserves and the need to reduce carbon emissions. A long term solution for passenger cars could be the introduction of battery electric vehicles (BEVs). However, one of the main problems associated with the current generation of BEVs is their short range relative to conventional internal combustion engine (ICE) cars.

To investigate this issue, a long range battery electric vehicle, the UltraCommuter (UC), was constructed by the University of Waikato in partnership with HybridAuto Ltd. This paper describes the development, modelling and testing of the UC and its performance in the 2007 World Solar Challenge.

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Personal passenger transport faces several challenges in the coming decades: depletion of cheap oil reserves, increasing congestion, localised pollution, the need for reduced carbon emissions and the long term goal of sustainability. One way of solving some of these problems could be to introduce comfortable, energy efficient, battery electric vehicles.

Currently, hybrid vehicles have been presented as a means to reducing the transportation related oil demand. New developments in materials and technologies have made them, cleaner and safer as well as more fuel efficient. However, hybrids will only prolong the use of oil until alternatively fuelled vehicles are developed.

One long term alternative is the battery electric vehicle (BEV). A BEV designed to be light, aerodynamic with high efficiency drive train and latest battery technology would have a performance comparable to a typical internal combustion engine vehicle (ICEV). Recent developments in virtual engineering, rapid prototyping and advanced manufacturing might enable low-cost development of niche market BEV’s designed and built in New Zealand for export markets.

This work examines the collaborative development of a twin seat BEV using new materials and latest technologies by the University of Waikato’s Engineering Department and a group of NZ and foreign companies. The car will be used to research the potential of BEVs and will also compete in the Commuter Class of the World Solar Challenge in 2007.

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This paper investigates whether low technology driver-only, battery electric commuter vehicles are feasible for New Zealand. Personal passenger transport faces several challenges in the coming decades: depletion of cheap oil reserves, increasing congestion, localised pollution, the need for reduced carbon emissions and the long term goal of sustainability. One way of solving some of these problems could be to introduce low cost, comfortable, energy efficient, driver-only electric vehicles. These would still give the driver a weatherproof, safe and comfortable means of commuting, but at a fraction of the energy and running costs of conventional petrol/diesel cars. To help assess their viability, the performance and energy use of the E-POD electric commuter vehicle is used as a benchmark. The work shows that such a vehicle could be made cheaply, using readily available technology with a range of 180km and a top speed of over 90km/h. The chassis could be made from natural fibre composite materials that might reduce significantly the embedded energy required for its manufacture. The electricity taken from the grid to charge the batteries could be replaced by electricity generated from grid connected photovoltaic panels mounted on the garage roof of the vehicle owner.

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The project investigated factors which may determine operator performance in X-ray screening of cargo, which is of similar importance to aviation security screening. A target detection paradigm showed significant difference in several measures of performance between baggage and postal contexts which provides evidence that these may constitute separate expertise domains.

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Advanced high strength steels (AHSS), in particular, are an attractive group materials, offering higher strength for improved energy absorption and the opportunity to reduce weight through the use of thinner gauges. High pressure tube hydroforming (HPTH) has been used to produce safety components for these steels, but it is expensive. Low pressure tube hydroforming (LPTH) is a lower cost alternative to form the safety components in the car. The side intrusion beam is the second most critical part after front rail in the car structure for passenger safety during crash. The forming as well as crash behaviour of a square side intrusion beam from both processes was investigated using numerical simulation. This paper investigated the interaction between the forming and crash response of these materials in order to evaluate their potential for use in vehicle design for crashworthiness. The energy absorption characteristics of the different tubes were calculated and the results from the numerical analyses compared for both hydroforming process.

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A pneumatic vehicle is provided with a chassis, wheels, a compressed air tank, a heat exchanger to heat the compressed air, and an air motor driven by the heated air and connected to at least one wheel. A pneumatic vehicle is provided with a chassis, wheels, a compressed air tank, and an air motor driven by the compressed air and connected to a wheel. The vehicle also has a ventilation system for the passenger compartment, a heat exchanger, and a restrictive solenoid valve for directing ventilation system air to the heat exchanger. A pneumatic vehicle is provided with a chassis, wheels, an aluminum compressed air tank, a carbon filament reinforced plastic layer over the tank, a fiberglass and aramid-fiber layer over the carbon filament reinforced plastic layer, and an air motor driven by the compressed air and connected to at least one wheel.

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The current automotive industry and todays car drivers are faced with every increasing challenges, not previously experienced. Climate Change, financial issues, rising fuel prices, increased traffic congestion and reduced parking space in cities are all leading to changes in consumer preferences and the requirements of modern passenger vehicles. However, despite the shift in the industry dynamics, the principal layout of a car hasn’t changed since its invention. The design of a ’conventional’ vehicle is still principally a matchbox with four wheels, one at each corner. The concept has served its purpose well for over 100 years, but such a layout is not suited to solving today’s problems. To address the range of problems faced by the industry, a number of alternative commuting vehicles have been developed. Yet the commercialization of these ‘alternative’ vehicles has yet to be successful. This is largely due failure of these vehicles to meet the changing demands of the industry and the limited understanding of consumer behaviour, motivation and attitudes. Deakin University’s Tomorrow’s Car concept tackles all of these problems. The vehicle is a novel three-wheeler cross over concept between a car and a motorbike that combines the best of both worlds. The vehicle combines the low cost, small size and ‘fun’ factor of a motorbike together with the safety, comfort and easy to drive features of a car produce a vehicle with a fuel efficiency better than either car or scooter. Intensive market research has been conducted for various major potential markets of alternative vehicles including India, China and Australia. The research analysed consumer attitudes in relation to narrow tilting vehicles, and in particular towards Deakin’s Tomorrow’s Car (TC). The study revealed that a relatively large percentage of consumers find such a concept very appealing. For the other consumers, the overall appearance and perception of safety and not the actual safety performance were found to be the most impeding factors of such vehicles. By addressing these issues and marketing the vehicle accordingly the successful commercialization of Tomorrow’s Car can be ensured.

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The lack of comprehensive data on transport operations is a long- standing problem in transport research. Information on road transport in particular has proved difficult to obtain. This Paper documents a study which was aimed at developing and testing a technique to estimate long-distance passenger and freight movements based on direct observation of vehicle movements.

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The desire to reduce carbon emissions due to transportation sources has led over the past decade to the development of new propulsion technologies, focused on vehicle electrification (including hybrid, plug-in hybrid and battery electric vehicles). These propulsion technologies, along with advances in telecommunication and computing power, have the potential of making passenger and commercial vehicles more energy efficient and environment friendly. In particular, energy management algorithms are an integral part of plug-in vehicles and are very important for achieving the performance benefits. The optimal performance of energy management algorithms depends strongly on the ability to forecast energy demand from the vehicle. Information available about environment (temperature, humidity, wind, road grade, etc.) and traffic (traffic density, traffic lights, etc.), is very important in operating a vehicle at optimal efficiency. This article outlines some current technologies that can help achieving this optimum efficiency goal. In addition to information available from telematic and geographical information systems, knowledge of projected vehicle charging demand on the power grid is necessary to build an intelligent energy management controller for future plug-in hybrid and electric vehicles. The impact of charging millions of vehicles from the power grid could be significant, in the form of increased loading of power plants, transmission and distribution lines, emissions and economics (information are given and discussed for the US case). Therefore, this effect should be considered in an intelligent way by controlling/scheduling the charging through a communication based distributed control.

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The evolution of domestic air travel service in Japan is a product of many factors including airline responses to the changing aviation market, government interventions in terms of regulatory/deregulatory policies, infrastructure investments, and changes in market structure. This paper presents an empirical investigation of the changing quality of passenger airline service and its implications in the domestic aviation market in Japan using qualitative review and a time series analysis of the domestic airline markets from 1986 to 2003. The results show that to meet the ultimate aim of deregulation to increase air passengers’ welfare gain, there is a need to instill measures to correct service imbalance and to create innovative airport demand-capacity management measures.

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Background: Occupational light vehicles (OLV) are light passenger and loadshaped vehicles used for work. The OLV-associated injury burden is as great as that of heavy vehicle users, but has been largely ignored by occupational health and safety (OHS) regulators. Contingent employment growth has accentuated existing gaps in the policy framework between OHS and road-safety. Frequent burden shifting from OHS to road-related health systems undermines the evidence base necessary to inform policy development. Aims: To provide evidence-based recommendations for the collection of OLVuser surveillance data and to underpin OHS procedures and policies for OLVusers. Method: The literature was systematically analyzed to identify OLV-user OHS policy and practice gaps. Strategies to improve and co-ordinate surveillance systems were developed to address the identified limitations. Results: Gaps were identified in OLV-user legislation, data collection, and riskmanagement. These require strategies to improve identification of all OLV-users and to co-ordinate surveillance and OHS practice. Discussion: Contemporary reform of road and OHS, policy, provides a timely opportunity for the implementation of strategic responses to this serious road safety and occupational, public health problem.

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Analysis of airport and air cargo operations is commonly performed in isolation, sharing only simple information such as flight schedules. Systems theory and Systems methodology can enhance such analysis by considering all aspects of air operations. It provides the decision-maker with an improved understanding of the implication of policy decisions, resource allocations and infrastructure investment strategies, through the capture of emergent behaviours and interdependencies. For example, the term airport operations, initially reminds us of the thought of passengers being transported by aircraft. Deeper thinking would identify activities that affect passenger operations, such as baggage handling systems, aircraft maintenance, and passenger security. In reality, airport operations consist of numerous aspects, including; concourses, runways, airlines, fuel depots, cargo terminal operators, retail, parking, cleaning, catering and many interacting people including travellers, service providers and visitors. For the airport to function effectively, these numerous systems must work together. This talk will focus on new tools and methodologies that are required for model development and analysis. It will then focus on modelling, simulation and analysis of the airport operations, providing greater understanding of airport operation with an emphasis towards security.

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In this study, we investigated the differential actions of a dominant-negative survivin mutant (SurR9-C84A) against cancerous SK-N-SH neuroblastoma cell lines and differentiated SK-N-SH neurons. In both the cases, the mutant protein displayed dual actions, where its effects were cytotoxic toward cancerous cells and proliferative toward the differentiated neurons. This can be explained by the fact that tumorous (undifferentiated SK-N-SH) cells have a high endogenous survivin pool and upon treatment with mutant SuR9-C84A causes forceful survivin expression. These events significantly lowered the microtubule dynamics and stability, eventually leading to apoptosis. In the case of differentiated SK-N-SH neurons that express negligible levels of wild-type survivin, the mutant indistinguishably behaved in a wild-type fashion. It also favored cell-cycle progression, forming the chromosome-passenger complex, and stabilized the microtubule-organizing center. Therefore, mutant SurR9-C84A represents a novel therapeutic with its dual actions (cytotoxic toward tumor cells and protective and proliferative toward neuronal cells), and hence finds potential applications against a variety of neurological disorders. In this study, we also developed a novel poly(lactic-co-glycolic acid) nanoparticulate formulation to surmount the hurdles associated with the delivery of SurR9-C84A, thus enhancing its effective therapeutic outcome.

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Research from around the globe has long emphasised the problem of vertical segregation in the news media where women remain largely absent from key editorial decision-making roles. Horizontal segregation, however, where there are gendered divisions of tasks associated with reporting, is also an ongoing issue and has been highlighted in a recent large-scale survey of female journalists in Australia. To date, just one other small industry survey in 1996 has asked female journalists in Australia about the types of stories that they cover and raised the implications of gendered inequity. This current survey finds that while more female reporters appear be covering hard news rounds like politics and business, the majority are still assigned to cover the bulk of the soft news areas of features, the arts, education and health—and most perceive that female reporters remain pigeon-holed in those traditionally female story areas. Respondents understand soft news as less important within the organisation in comparison to the highly valued areas of politics and sports that male reporters most often cover. This paper analyses female journalists' responses to the gendered nature of the soft news–hard news binary and the ramifications of such disparity.