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71.
Artificial islands have been constructed next to large cities due to the need for extra space in highly populated areas. These emerged structures have been used by many countries as platforms for developing infrastructure (airports, harbors, highways, etc.), rebuilding ecological areas, and creating new spaces for tourism or residential areas. In this study, two state-of-the-art numerical models for wave propagation and nearshore circulation are used to simulate the effects of an emerged artificial island on the Barcelona coast. Several sea indicators (wave height, intensity and direction of currents, and mean water level) are analyzed to assess the changes likely to be induced by an artificial island. Three different situations are studied and the indicators are compared across the different tests to obtain information that can be used in the planning process of these structures. In two-meter wave conditions, the tests show that wave height is generally reduced in the sheltered area, which leads to improved safety for beach users (bathing is prohibited when wave height exceeds the two-meter threshold). However, the numerical models also reveal that velocities in the sheltered area usually decrease, which must be controlled to prevent stagnation in the bathing area.  相似文献   
72.
Abstract

This paper looks at estimated valuations of some service‐quality attributes in an airline choice context using stated preferences methods. The analysis is based on information obtained in the most important route connecting the Canary Islands with the Iberian Peninsula: Gran Canaria–Madrid, and tries to contribute to the body of knowledge in this area, given the relatively few studies of the monetary valuations of air travel regarding level‐of‐service attributes. A feature of this analysis is the examination of variations in values according to different characteristics of the service, such as price, penalties for changes in the ticket, legroom, food, etc.; the currently experienced level of the attribute, and various socio‐economic factors that affect the characteristics of the trip and passengers. In addition, the important issue of added value regarding different attributes is addressed, obtaining the willingness‐to‐pay for different improvements of service quality. A further analysis is made about how taste heterogeneity (market segments) affects these values. Results from the stated preference experiment and the market value of some comparable service are also compared. Finally, the paper brings together evidence from other studies and compares them with the findings obtained herein.  相似文献   
73.
Short sea shipping (SSS) is called to play a key role in ensuring sustainable mobility in the European context. In the past years several studies tried to define the SSS requirements and also to identify the SSS lines that were economically viable. However, no studies approach the profile of their users—the road transport firms—and the organizational patterns adopted by them, in order to gain a better understanding of this transport modality. This research, on the basis of a sample of 81 international road transport firms that use SSS between Spain and Italy, analyses the profile of these firms and certain elements inherent to their relationship with the shipping firms, according to the two modalities of organizing their SSS transport operations: accompanied versus unaccompanied.  相似文献   
74.
Abstract

This paper concerns the newspaper distribution problem. It addresses the transportation of newspapers from printing plant to newsagents with distribution vehicles under various particular constraints. The objective is to minimize the distance traveled by the vehicles and/or the number of vehicles. In this study, the routes for vehicles of a leading newspaper distributor company in the Turkish press sector are examined. The problem is defined as determining optimal delivery routes for a fleet of homogeneous vehicles, starting and ending at the printing plant that is required to serve a number of geographically dispersed newsagents with known demands under capacity and time constraints, while minimizing the total distribution cost. An integar linear programming model is proposed as a solution using Cplex. Computational results demonstrate that the proposed model is fast and able to find optimal solutions for problem scenarios with up to 55 newsagents within reasonable computing times. It was found that the proposed model reduced the delivery cost by 21% on average when compared to the current manual method. The results show that this model is adequate for medium-sized distribution problems.  相似文献   
75.
Transportation - Understanding the link between mode choice and travel satisfaction is essential for promoting sustainable travel by expanding utility theory to include also the eudaimonic value of...  相似文献   
76.
Journal of Marine Science and Technology - This paper presents a procedure for the estimation of propeller effective wakes in oblique flows. It shows how a recently developed method for controlling...  相似文献   
77.
Transportation - Reliability is understood in public transport as the certainty travellers have regarding the level of service they will experience when travelling. The travel time, waiting time,...  相似文献   
78.
Transportation - Sidewalk cyclists are a major concern to planners in many cities around the world: they are considerable in numbers, and increase the risk of injury not only to pedestrians but...  相似文献   
79.
In the quest for sustainable travel, short distances appear the most amenable to curbing the use of the automobile. Existing studies about short trips evaluate the potential of shifting from the automobile to sustainable travel options while considering the population as homogeneous in its preferences and its tendency to accept these alternative travel options as realistic. However, this assumption appears quite unrealistic and the current study offers a different perspective: the mode choices when travelling short distances are likely related to lifestyle decisions. Short trip chains of a representative sample of the Danish population in the Copenhagen Region were analysed, and more specifically a latent class choice model was estimated to uncover latent lifestyle groups and choice specific travel behaviour. Results show that four lifestyle groups are identified in the population: car oriented, bicycle oriented, public transport oriented and public transport averse. Each lifestyle group has specific perceptions of travel time (with extremely different rates of substitution between alternative travel modes), transfer penalties in public transport trip chains, weather influence (especially on active travel modes), and trip purpose effect on mode selection. Consequently, when thinking about measures to increase the appeal of sustainable travel options, decision-makers should look at specific individuals within the population and more sensitive individuals to comfort and level-of-service improvements across the lifestyle groups.  相似文献   
80.
The City of Madrid is putting into operation Intermodal Exchange Stations (IESs) to make connections between urban and suburban transportation modes easier for users of public transportation. The purpose of this article is to evaluate the actual effects that the implementation of IESs in the City of Madrid has on the affected stakeholders: users, public transportation operators, infrastructure managers, the government, the abutters and other citizens. We develop a methodology intended to help assess the welfare gains and losses for each stakeholder. Then we apply this methodology to the case study of the Avenida de América IES in the city of Madrid. We found that it is indeed possible to arrive at win?Cwin solutions for the funding of urban transportation infrastructure, as long as the cost-benefit ratio of the project is high enough. Commuters save travel time. Bus companies diminish their costs of operation. The abutters gain in quality of life. The private operator of the infrastructure makes a fair profit. And the government is able to promote these infrastructure facilities without spending more of its scarce budgetary resources.  相似文献   
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