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191.
This paper investigates the potential for deliberation as a means for public participation in shaping public policy. The paper begins with a summary of deliberative democracy and other concepts that recently have motivated an interest for online deliberation. Next, the paper describes a case study in which 133 public participants deliberated over a regional transportation improvement decision. The deliberation occurred entirely over the internet and lasted for 31 days. The participants wrote hundreds of posts (comments) and made thousands of post-ratings (statements of agreement or disagreement). The posts and three questionnaires are analyzed quantitatively and qualitatively to assess the nature of the deliberation and the participants’ perception of their experience. A negative binomial regression is used to examine which participant characteristics are associated with writing more posts.  相似文献   
192.
Real data show that reserving a lane for carpools on congested freeways induces a smoothing effect that is characterized by significantly higher bottleneck discharge flows (capacities) in adjacent lanes. The effect is reproducible across days and freeway sites: it was observed, without exception, in all cases tested. Predicted by an earlier theory, the effect arises because disruptive vehicle lane changing diminishes in the presence of a carpool lane. We therefore conjecture that smoothing can also be induced by other means that would reduce lane changing.The benefits can be large. Queueing analysis shows that the smoothing effect greatly reduces the times spent by people and vehicles in queues. For example, by ignoring the smoothing effect at one of the sites we analyzed one would predict that its carpool lane increased both the people-hours and the vehicle-hours traveled by well over 300%. In reality, the carpool lane reduced both measures due to smoothing. The effect is so significant that even a severely underused carpool lane can in some instances increase a freeway bottleneck’s total discharge flow. This happens for the site we analyzed when carpool demand is as low as 1200 vph.  相似文献   
193.
194.
We verify that slow speeds in a special-use lane, such as a carpool or bus lane, can be due to both, high demand for that lane and slow speeds in the adjacent regular-use lane. These dual influences are confirmed from months of data collected from all freeway carpool facilities in the San Francisco Bay Area. Additional data indicate that both influences hold: for other types of special-use lanes, including bus lanes; and for other parts of the world.The findings do not bode well for a new US regulation stipulating that most classes of Low-Emitting Vehicles, or LEVs, are to vacate slow-moving carpool lanes. These LEVs invariably constitute small percentages of traffic; e.g. they are only about 1% of the freeway traffic demand in the San Francisco Bay Area. Yet, we show: that relegating some or all of these vehicles to regular-use lanes can significantly add to regular-lane congestion; and that this, in turn, can also be damaging to vehicles that continue to use the carpool lanes. Counterproductive outcomes of this kind are predicted first by applying kinematic wave analysis to a real Bay Area freeway. Its measured data indicate that the site selected for this analysis stands to suffer less from the regulation than will others in the region. Yet, we predict: that the regulation will cause the site’s people-hours and vehicle-hours traveled during the rush to each increase by more than 10%; and that carpool-lane traffic will share in the damages. Real data from the site support these predictions. Further parametric analysis of a hypothetical, but more generic freeway system indicates that these kinds of negative outcomes will be widespread. Constructive ways to amend the new regulation are discussed, as are promising strategies to increase the vehicle speeds in carpool lanes by improving the travel conditions in regular lanes.  相似文献   
195.
This paper provides an analysis of the development of the liner route between the UK and Poland and the activities of the two main operators—EuroAfrica of Poland and United Baltic Corporation of London. The most significant factors driving the development of this trade are analysed using a combination of an industrial survey and government statistics for the route, before going on to examine the threat to the trade presented by the growth of the trucking mode.  相似文献   
196.
There are numerous possible advantages to be gained from the accurate prediction of future movements in the Baltic Freight Index (BFI). Because of the difficulties inherent in long-range forecasting, however, the potential for such predictions to provide insight into the future state of the physical dry bulk market is perhaps limited. The greater accuracy of short-term forecasts, on the other hand, facilitates the development of a forecasting model form is justified by the inevitably continuous nature of futures market speculation. Such a model is developed through the application of the Box—Jenkins approach to time series analysis and forecasting. The methodology is presented and the resulting model is evaluated on the basis of objective measures of predictive power and by comparison with alternative forecasting models. Finally, the applicability of the model to the practice of BIFFEX speculation is assessed by judging its performance within a simulated BIFFEX trading environment.  相似文献   
197.
Despite the importance of assessing the reliability of transport networks in general there is a paucity of suitable techniques. In part this is due to the fact that network performance depends both on the state of the infrastructure and on the behaviour of network users, where user behaviour is governed by expectations about the state of the network. An approach based on game theory is proposed whereby the performance of the network is estimated for the case where network users are extremely pessimistic about the state of the network. Where the routes are prespecified and route utilities depend only on exogenously given scenarios, the estimation problem may be formulated as a linear program. A reformulation of the problem as a non-linear program allows the impact of the degree of user pessimism on expected network utility to be studied. The problems of implementing the method for large networks with multiple origins and destinations is discussed and an algorithm is proposed.  相似文献   
198.
最近,对铁道车辆防火条例进行了大量改动。由于欧洲防火标准要统一,相比个别国家标准例如DIN5510,对防火文件和列车零部件质量做出了额外要求。  相似文献   
199.
A vehicle system dynamics model is presented that captures the essential braking and handling behavior of a passenger car and runs faster than real-time on a 1998 Pentium 233 MHz laptop computer. The simulation code was generated with the AutoSim multibody code generator and linked with C functions that communicate with braking hardware to create a real-time simulation (RTS) with hardware in the loop (HITL). Techniques are described that were used to allow the simulation program to work with HITL. The model (without controller) was also integrated with the Simulink environment to provide a design tool for control engineers.  相似文献   
200.
Shipping companies’ crucial need for cost cutting is their main motive for recruiting seafarers of various nationalities and formulating multicultural teams on board ships. This paper seeks to examine ways of dealing with cultural issues by being a socially responsible company. The main point of the research is to examine how managing multicultural crews is related to the shipping companies’ and the industry’s social responsibility. An extensive literature review on the cultural issues of maritime manpower, with a focus on the working and living conditions and the management of shipping crews, reveals important aspects of the subject. This analysis is enriched with qualitative data from an on-board case study, and from a survey among crew managers and manning agents. Results show that managing multicultural human resources in a socially responsible manner requires socially acceptable behaviour towards seagoing labour from all the industrial actors.  相似文献   
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