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311.
312.
This paper investigates a parking reservation mechanism to reduce car cruising to find parking. To consider the benefits for drivers and parking facility providers, we charge drivers for making reservations in addition to parking fees, by introducing a reservation pricing model that makes reservation prices equivalent to the value of saved search time. By modeling the number of vacant spaces as a stochastic variable, and applying binomial pricing methods, parking reservation prices are obtained. Numerical examples based on the data for two parking facilities in Taiwan are given.  相似文献   
313.
The day-long system optimum (SO) commute for an urban area served by auto and transit is modeled as an auto bottleneck with a capacitated transit bypass. A public agency manages the system’s capacities optimally. Commuters are identical except for the times at which they wish to complete their morning trips and start their evening trips, which are given by an arbitrary joint distribution. They value unpunctuality – their lateness or earliness relative to their wish times – with a common penalty function. They must use the same mode for both trips. Commuters are assigned personalized mode and travel start times that collectively minimize society’s generalized cost for the whole day. This includes unpunctuality penalties, queuing delays, travel times and out-of-pocket costs for users, as well as travel supply costs and externalities for society.It is shown that in a SO solution there can be no queuing and that the set of SO solutions forms a convex set. Furthermore, if the schedule penalty that users suffer due to unpunctuality is separable into morning and evening components, then the set of commuters traveling by the same mode arrive at work and depart from work in the order of their wishes. These orders are in general different in the morning and the evening. It is also shown that there always is a SO solution in which users are at all times, and on both modes, either punctual or flowing at capacity. These problem properties are used to identify search methods, both, for SO solutions and for time-dependent tolls and transit fares that preserve the solutions as Nash equilibriums. In every case studied, these prices exist. They must peak concurrently for the two modes in both periods.In special cases involving only one mode, only one period or concentrated demand the solution to the complete problem decomposes by period conditional on the number of transit users, and this facilitates the solution. In these cases the day-long SO cost is the sum of the SO costs for the two peaks considered separately. However, this is not true in general – the solution obtained by combining the two single-period solutions can be infeasible. When this happens, the optimum day-long cost will exceed the sum of the single-period costs. The discrepancy is about 40% of the total schedule penalty for an example representing a large city. Thus, to develop realistic policies the day-long problem must be addressed head on. An approximate method that yields closed form formulas for the case with uniformly distributed wishes is presented.  相似文献   
314.
We compare the passenger transportation systems of Buenos Aires, Chicago and São Paulo. The selected cities represent distinctive combinations of land-use, infrastructure, and evolution of transport policy. Analysis is centered on accessibility to downtown areas, where transportation processes converge in an environment where space is scarce. In two of the three cities institutional arrays that legally establish unified decision making have shown little capacity to launch fare or physical coordination between modes. In two of the three cities the concentration of public transportation supply to historical downtowns has not been an attraction factor, and downtown uses have expanded to less accessible areas. Gentrification in Chicago is also another process showing that land use changes are related to many factors, transportation being only one of them, and not always a necessary one. In all three cases the use of railways, as a set of inherited infrastructures, has seen an increase whose magnitude suggests a link to modal reassignment due to increasing congestion. Scarcity of space in old downtown areas is being counteracted through more intense use, or through the expansion of vertical space for transportation operations.  相似文献   
315.
要实现在具有自然垄断性质的网络行业中引入竞争、提高效率和履行普遍服务义务的双重目标,政策制定者有必要引入一些竞争中性的规制措施.介绍了统一定价、价格上限和范围限制等几项措施及措施组合的内容,通过一个实证性模型,分析了各种情况下在位者和进入者均衡价格和均衡服务范围的决定.结论:在没有明确其他措施的内容时,单一措施的福利评价是不可能的,必须将同时发挥作用的各项措施结合起来进行综合评价.并且,政策制定者在制定各项措施时,必须在提供更大的服务范围、提高接受服务的消费者福利、提高垄断地区消费者福利和提高竞争地区消费者福利之间做出权衡.  相似文献   
316.
First-best marginal cost toll for a traffic network with stochastic demand   总被引:1,自引:0,他引:1  
First-best marginal cost pricing (MCP) in traffic networks has been extensively studied with the assumption of deterministic travel demand. However, this assumption may not be realistic as a transportation network is exposed to various uncertainties. This paper investigates MCP in a traffic network under stochastic travel demand. Cases of both fixed and elastic demand are considered. In the fixed demand case, travel demand is represented as a random variable, whereas in the elastic demand case, a pre-specified random variable is introduced into the demand function. The paper also considers a set of assumptions of traveler behavior. In the first case, it is assumed that the traveler considers only the mean travel time in the route choice decision (risk-neutral behavior), and in the second, both the mean and the variance of travel time are introduced into the route choice model (risk-averse behavior). A closed-form formulation of the true marginal cost toll for the stochastic network (SN-MCP) is derived from the variational inequality conditions of the system optimum and user equilibrium assignments. The key finding is that the calculation of the SN-MCP model cannot be made by simply substituting related terms in the original MCP model by their expected values. The paper provides a general function of SN-MCP and derives the closed-form SN-MCP formulation for specific cases with lognormal and normal stochastic travel demand. Four numerical examples are explored to compare network performance under the SN-MCP and other toll regimes.  相似文献   
317.
Demand and capacity fluctuations are common for roads and other congestible facilities. With ongoing advances in pricing technology and ways of communicating information to prospective users, state-dependent congestion pricing is becoming practical. But it is still rare or nonexistent in many potential applications. One explanation is that people dislike uncertainty about how much they will pay. To explore this idea, a model of reference-dependent preferences is developed based on Köszegi and Rabin (2006). Using a facility yields an “intrinsic” utility and a “gain-loss” utility measured relative to the probability distribution over states of utility outcomes. Two types of preferences are analyzed: bundled preferences in which gains and losses are perceived for overall utility, and unbundled preferences in which gains and losses are perceived separately for the toll and other determinants of utility.Tolls are chosen to maximize total expected utility plus revenues. With bundled preferences the toll is set above the Pigouvian level when usage conditions are good, and below it when conditions are bad, in order to reduce fluctuations in utility. With unbundled preferences the direction of toll adjustment is less clear and depends on whether supply or demand is variable. For both types of preferences tolls are sensitive to the strength of gain-loss utility. If gain-loss utility is moderately strong, a state-independent toll can be optimal.  相似文献   
318.
The objective of this study is to examine the effect of road pricing on people’s tendency to adapt their current travel behavior. To this end, the relationship between changes in activity-travel behavior on the one hand and public acceptability and its most important determinants on the other are investigated by means of a stated adaptation experiment. Using a two-stage hierarchical model, it was found that behavioral changes themselves are not dependent on the perceived acceptability of road pricing itself, and that only a small amount of the variability in the behavioral changes were explained by socio-cognitive factors. The lesson for policy makers is that road pricing charges must surpass a minimum threshold in order to entice changes in activity-travel behavior and that the benefits of road pricing should be clearly communicated, taking into account the needs and abilities of different types of travelers. Secondly, earlier findings concerning the acceptability of push measures were validated, supporting transferability of results. In line with other studies, effectiveness, fairness and personal norm all had a significant direct impact on perceived acceptability. Finally, the relevance of using latent factors rather than aggregate indicators was underlined.  相似文献   
319.
停车收费价格是规范居住区停车管理的重要手段.结合北京市居住区停车成本调查,分析居住区停车泊位运营管理成本;结合北京市居住区停车行为调查,探讨居民对停车费用的支付意愿及其与居民收入的关系,据此确定居住区停车收费依据.进而考虑与居民停车泊位选择行为密切相关的影响因素,建立BL模型,分析地面停车泊位与室内停车泊位的费用差价对...  相似文献   
320.
At the time of writing (2010), the world is witnessing the aftermath of the most severe financial sector meltdown in modern economic history caused by the real estate bubble in the United States. Its consequences on the real economy, especially in Europe, are yet to be fathomed, and this of course includes the longer-term impacts on international ocean transportation, ports and the distribution of global production.The economic recession has left the international shipping and port sectors with substantial overcapacity. This has resulted in drastic cost cutting measures on the one hand, and voluntary, often consensual, and coordinated reduction of supply on the other. These measures, together with a noticeable recovery in demand, are gradually leading again to improvement in prices charged by carriers and other transport service providers.In view of the country’s expanse; size of population; and regional inequalities, India’s dry ports (inland cargo consolidation and distribution centres) are seen by the government as a pivot of export-led growth and economic development (Haralambides & Gujar, 2011). Moreover, public and private sectors alike see the coordinated development of dry ports as the only way forward in terms of easing pressures at congested coastal ports, thus improving supply chain efficiency. In spite of this, dry port development and operations are still dominated by the public sector, under prices, capacity, land acquisition policies and other conditions that make private sector participation risky and comparatively unattractive. In order to rationalize dry port capacity and prices, this paper argues in favour of greater devolution through competition-enhancing Public-Private Partnerships (PPPs). The paper puts forward recommendations for the necessary legal, regulatory and general economic policy interventions based on international best practice, while keeping Indian specificities in the right perspective.  相似文献   
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