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621.
622.
Cycling and walking are being promoted in many urban areas as alternatives to motorised transport for health, environmental, and financial reasons. The reduced congestion and resulting decrease in the overall amount of pollution reduced can be expected to result in health benefits for the community. However, active commuters, due to their increased respiration rates and often increased travel times can expect to receive larger doses of air pollution compared with those using motorised forms of transport. However, given the large dropoff in concentrations away from a road, it can be expected that significant reductions can be achieved even with relatively small increases in separation between the path of cyclists/pedestrians and motor vehicles.This study presents a simple methodology for calculating the separation needed for cyclists and pedestrians to experience the same air pollution dose as car commuters. An example is given based on carbon monoxide (CO) data collected in a field campaign consisting of a car driver, a cyclist and a pedestrian travelling on a 2600 metre loop of road in Auckland. For this case study, the estimated distance from the centreline needed for cyclists and pedestrians to receive an equivalent dose of CO as motorists was found to range from 5.8 to 14.2 m depending on the commuting mode and the dispersion state of the atmosphere at the site. This was equal to a CO concentration reduction of 0.1–0.14 ppm per metre. Recommendations on facility modifications and route selections have been made to make active mode commuting safer. 相似文献
623.
管道挖沟动力定位工程船是一艘集首部拖缆作业系统、尾部拖缆作业系统以及其他多项水下作业功能的海底施工作业船舶,为配合其作业功能,对诸多大型作业设备进行结构加强,并创新性地设计凹形首柱拖缆槽和导缆圆尾。通过计算分析,对横剖面进行优化,校核总纵强度以及校核主要设备加强结构的局部强度,对船体振动进行评估并采取一定的减振措施。 相似文献
624.
This study examines the users’ acceptance and usage of mobile payments, focusing on the mobile ticketing technologies applied in a public transport context. We investigate the main predictors of the intention to use mobile ticketing and the relation between those predictors, considering the prominent literature on users’ technology acceptance background and extending the knowledge through an innovative contribution. The main models of reference in this study are the Technology Acceptance Model (TAM), the Diffusion of Innovation Model (DOI) and the Unified Theory of Acceptance and Use of Technology (UTAUT) model. The new model that we proposed is called the Integrated Model on Mobile Payment Acceptance (IMMPA), and it was designed specifically for mobile payments in the public transport, on the basis of the models previously mentioned. It was developed by mixing the variables of the existing models and adding new ones tailored to the mobile payment/ticketing framework. The theoretical framework was tested using the Structural Equation Models. The results show that the intention to use a technology is affected by the Usefulness, Ease of use and the Security of that technology. Moreover, the Usefulness is simultaneously influenced by the Ease of use, the Compatibility with users’ values and needs and their Attitude towards mobile services. Furthermore, the model confirms the direct relation between the intention to use a technology and its actual usage. The new predictor, that is the Attitude towards mobile services, includes those requirements that every mobile ticketing payment must address in this context: complete information, further information about time and delay, speed of use, intuitive interface, and path customisation. Another new construct detected is the Security, in reference to mobile payment. Because it could represent an obstacle to mobile ticketing distribution, it must be considered by market operators. The originality of the paper addresses the realisation of a new model, the IMMPA, which was specifically designed for mobile payment in the public transport. 相似文献
625.
626.
In this paper, graphical-user-interface (GUI) software for simulation and fuzzy-logic control of a remotely operated vehicle (ROV) using MATLABTM GUI Designing Environment is proposed. The proposed ROV... 相似文献
627.
Driven by sustainability objectives, Australia like many nations in the developed world, is considering the option of battery electric vehicles (BEVs) as an alternative to conventional internal combustion engine vehicles (ICEVs). In addition to issues of capital and running costs, crucial questions remain over the specifications of such vehicles, particularly the required driving range, recharge time, re-charging infrastructure, performance, and other attributes that will be of importance to consumers. With this in mind, this paper assesses (hypothetically) the extent to which current car travel needs could be met by BEVs for a sample of motorists in Sydney assuming a home-based charging set-up, which is likely to be the primary option for early adopters of the technology. The approach uses five weeks of driving data recorded by GPS technology and builds up home-home tours to assess the distances between (in effect) charging possibilities. An energy consumption model based on characteristics of the vehicle, and the speeds recorded by the GPS is adapted to determine the charge used, while a battery recharge function is used to determine charging times based on the current battery level. Among the most pertinent findings are that over the five weeks, (i) BEVs with a range as low as 60 km and a simple home-charge set-up would be able to accommodate well over 90% of day-to-day driving, (ii) however the incidence of tours requiring out-of-home charging increases markedly for vehicles below 24 kWh (170 km range), (iii) recharge time in itself has little impact on the feasibility of BEVs because vehicles spend the majority of their time parked and (iv) effective range can be dramatically impacted by both how a vehicle is driven and use of electrical auxiliaries, and (v) while unsuitable for long, high-speed journeys without some external re-charging options, BEVs appear particularly suited for the majority of day-to-day city driving in big cities where average journey speeds of 34 km/h are close to optimal in terms of maximising vehicle range. The paper has implications for both policy-makers and auto manufacturers in breaking down some of the (perceived) barriers to greater uptake of BEVs in the future. 相似文献
628.
629.
本文简要论述了城市公交智能信息系统的构成及其实施的必要性,分析了各子系统的主要作用及相互关系,在通常采用的公交智能信息系统的基础上又提出了一套新的开发思路,同时对所涉及的相关的关键技术如GPS、GIS 等作了简要的介绍和分析。 相似文献
630.
核反应堆压力壳螺栓孔检测自动小车的定位 总被引:1,自引:0,他引:1
设计了能在高辐射环境下工作的、全自动检查核电站反应堆压力壳连接处法兰面主螺栓孔螺纹表面缺陷的设备,解决了自动小车的设备承载和准确定位问题.自动小车在移动中靠法兰面被测螺栓孔定位,经现场检测其定位精度达到0.15mm,满足设计要求. 相似文献