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排序方式: 共有466条查询结果,搜索用时 15 毫秒
461.
车内有害气体分析和净化的有效途径   总被引:3,自引:0,他引:3  
通过车内有害气体对驾乘人员健康的危害性分析,介绍客车行业当前不容忽视的环保问题;结合国内客车车内空气污染的普遍现象,有针对性地提出相应的解决方法,特别指出新材料光触媒净化车内空气的科学性和有效性.  相似文献   
462.
CAN总线在混合动力电动公共汽车中的应用   总被引:3,自引:0,他引:3  
介绍了CAN总线及其通讯协议,结合混合动力电动汽车的特性阐述了CAN总线系统总体设计的思路。以混合动力内燃发电系统控制器为例,简要介绍CAN总线通信的软、硬件实现方法。该设计已应用在混合动力柴油发电机组控制器中,满足了控制需要。  相似文献   
463.
A key attribute of competitive tendering for the periodic selection of operators of subsidised public transport services is to secure the provision of specified services at efficient cost levels. This has proved particularly effective where services were previously provided by an inefficient monopoly operator. The arguments for the adoption of competitive tendering in preference to negotiation with the incumbent operator may be less clear-cut in other cases.Consideration is given to both theoretical and practical insights into the relative merits of competitive tendering and negotiation approaches in such situations. The limited literature on the topic is reviewed and insights and lessons identified. Influencing issues include prior conditions, the nature of the supplier market, features of contracts, negotiating and competitive tendering strategies and practice, accountability and transparency, and long-term market implications. The evidence suggests that ‘one size does not fit all’, and the choice will depend on specific circumstances.The relative merits of the two approaches for renewal of bus contracts are considered with regard to Adelaide, for contracts which have previously been awarded through competitive tendering. The paper draws out the main factors that could influence the authority’s choice between the options, and discusses the relevance of the findings to other situations.  相似文献   
464.
Workshop 1 was concerned to identify the real results of competitive tendering, and experience on how to make it work better, using evidence from the rail and bus sectors in a large number of countries spread around the world. It was found that competitive tendering had generally been successful in terms of quality and costs, but problems had occurred in a number of cases, so careful attention must be paid to the design of tendering exercises, details of the contract, risk-sharing arrangements and the approach to any re-negotiation found to be necessary. As a result, an important conclusion is that the tendering authority needs a high degree of expertise in these issues; any thought that competitive tendering relieves the public authority of the need for expertise in public transport is mistaken.  相似文献   
465.
Despite the many socio-economic similarities between Sweden and Norway, differences in jurisdiction, organisation, cooperation, and financing of long-distance passenger train and coach services have led to the development of four distinctively different ways of serving the markets. This paper describes how the train and coach markets have developed in the two countries, with emphasis on regulatory and industrial structure and a couple of performance variables.Looking at passenger rail, both countries separated infrastructure from operation over a decade ago. However, while Norwegian rail is characterised by an almost monopoly supplier, rail services in Sweden are partly decentralised to the responsibility of county authorities and are widely subjected to competitive tendering. The rest of the network is about to be opened up for on-the-track competition. Swedish Rail (SJ) has spent the last decades consolidating its core business (passenger rail) and sold out its other businesses. In contrast, the Norwegian state rail (NSB) has expanded its business to become a major bus operator and property owner, with extensions also into the Swedish market.The coach industry was more recently deregulated in both countries. The Swedish coach market is dominated by privately owned companies operating services to and from Stockholm. In Norway, state-owned NSB is a major coach operator on medium distance routes, and is also the largest partner of Nor-Way Bussekspress which totally dominates long-distance coach services. Further, the Norwegian coach market is characterised by cross-ownership and cooperation which has enabled an extensive route network which covers most of Norway.We find distinct differences in achievements in the two modes and in the two countries. Swedish rail services have succeeded in winning market shares and in renewing and developing both infrastructure and service levels to a greater extent than the Norwegian model. On the other hand, the Norwegian coach market seems to be more developed and efficient compared to its Swedish counterpart.The paper concludes with a discussion on the possible links between the different approaches and the performance observed, with the aim to stimulate further and more detailed research on some important issues.  相似文献   
466.
韩旗  徐国顺 《船舶》2010,21(6):42-43,67
针对舰船三相交流电力系统,提出了采用附加电容的对地电容测量方法,并设计出测量系统,进行了试验验证。证明该测量方法可以安全、准确地测量电网的对地电容,为电网消弧线圈设计选型提供了依据。  相似文献   
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