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101.
102.
Bicycle–motorised vehicle (BMV) collisions account for the majority of the recorded bicyclists’ fatalities and serious injuries. This systematic review intends to examine the main factors contributing to BMV collisions. We performed a comprehensive literature review on Scopus, TRID, ProQuest, and Web of Science databases. Fifty-nine English-language peer-reviewed articles met the eligibility criteria and were included in the final analysis. The main factors contributing to BMV collisions identified were classified in accordance with a recently published conceptual framework for road safety. The majority of studies have identified factors related to road users’ behaviour (59.3%) and infrastructure characteristics (57.6%). A minority of studies identified variables related to exposure (40.7%) and vehicles (15.3%) as contributor factors to BMV collisions. A small but significant proportion of studies (20.3%) provided evidence that environmental factors may also play a role, although to a lesser extent, in determining BMV collisions. In addition to the three factors comprised in the applied conceptual framework for road safety, we identified environmental conditions as a category of factors contributing to BMV collisions.  相似文献   
103.
This paper describes a real-time vision-based blind spot warning system that has been specially designed for motorcycles detection in both daytime and nighttime conditions. Motorcycles are fast moving and small vehicles that frequently remain unseen to other drivers, mainly in the blind-spot area. In fact, although in recent years the number of fatal accidents has decreased overall, motorcycle accidents have increased by 20%. The risks are primarily linked to the inner characteristics of this mode of travel: motorcycles are fast moving vehicles, light, unstable and fragile. These features make the motorcycle detection problem a difficult but challenging task to be solved from the computer vision point of view. In this paper we present a daytime and nighttime vision-based motorcycle and car detection system in the blind spot area using a single camera installed on the side mirror. On the one hand, daytime vehicle detection is carried out using optical flow features and Support Vector Machine-based (SVM) classification. On the other hand, nighttime vehicle detection is based on head lights detection. The proposed system warns the driver about the presence of vehicles in the blind area, including information about the position and the type of vehicle. Extensive experiments have been carried out in 172 minutes of sequences recorded in real traffic scenarios in both daytime and nighttime conditions, in the context of the Valencia MotoGP Grand Prix 2009.  相似文献   
104.
The State-owned Spanish Port System (SPS) includes 46 ports for general use that are managed by the 28 port authorities distributed along the 8000 km of Spanish coast. SPS has not grown at a rate comparable to that of international maritime transportation. In our paper, we start from the hypothesis of a port system that appears to be oversized, subsidized, with regard to container traffic. Quantifying the maximum operational capacity of the different container terminals along the Spanish coast and their mooring capacities will provide the available dimensions for this type of traffic. In a second step, we will analyse whether SPS are sufficient (according to the perspective of international standards) to meet Spain’s needs, which is related to Spain’s strategic geographic location and its need to move containerized cargo for the domestic market. The paper concludes SPS has an oversized that limits competitiveness, which is indicated by the average transshipment ratio of approximately 50% and an average unweighted idle ratio of port facilities designed for container traffic of over 60% in the eight main ports.  相似文献   
105.
Transportation - Based on a time-use model with a sound theoretical basis and carefully collected data for Austria, the value of leisure (VoL) for different population segments has been estimated....  相似文献   
106.
The paper analyzes the performance of different post-disaster humanitarian logistic structures that arose in response to the Port-au-Prince earthquake of January 12th, 2010. Based on field work conducted by the authors, the paper defines a typology of structures; assesses their relative performance in terms of delivering relief aid; and identifies the causes that explain the differences between them. Three structures are defined for comparative purposes: Agency Centric Efforts (ACEs), Partially Integrated Efforts (PIEs), and Collaborative Aid Networks (CANs). These structures differ to the extent to which they are integrated with the local social networks during the relief effort. Representative examples were analyzed to illustrate their inherent strengths and weaknesses, and reach conclusions of general applicability. The authors strengthen the analyses with discussions of “comparables,” i.e., other cases not fully discussed in the paper that shed additional light onto the performance of the structures.The paper’s analyses are based on dozens of interviews, both formal and informal, conducted with individuals directly involved in the relief effort, complemented with critical analyses of news accounts, and reports produced by the agencies involved. Based on its chief findings, the paper makes policy recommendations to maximize the effectiveness of future relief distribution efforts in response to disasters of various sizes.  相似文献   
107.
We develop a simplified model of choked flow in pipes for CO2-water solutions as an important step in the modelling of a whole hydraulic system with the intention of eliminating the carbon dioxide generated in air-independent submarine propulsion. The model is based on an approximate fitting of the homogeneous isentropic solution upstream of a valve (or any other area restriction), for given fluid conditions at the entrance. The relative maximum choking back-pressure is computed as a function of area restriction ratio. Although the procedure is generic for gas solutions, numeric values for the non-dimensional parameters in the analysis are developed only for choking in the case of carbon dioxide solutions up to the pure-water limit.  相似文献   
108.
Airport infrastructure in many countries is being up-graded to meet the growing demands of tourism, and air travel more generally, but this poses problems for sustainable development. Thus, there is the need to establish an alternative to the traditional airport pricing structure for landing fees so as to reflect the true cost that air transports imposes on others. This paper analyses one application of Ramsey pricing to some Spanish tourist airport that embraces environmental as well as conventional financial costs.  相似文献   
109.
This article deals with the influence of three-way catalysts on the production of basic emissions, such as carbon monoxide, unburned hydrocarbons and nitrogen oxides from spark-ignition engines. A virtual simulation of the new European driving cycle is used. Characteristics of components in emissions in the front and back of the catalyst are measured on the test bed to form the basis of the simulation. The results relate to emissions for 1 km travelled.  相似文献   
110.
A long run multioutput cost function for the infrastructure services of Spanish ports is estimated using 286 observations on 26 ports during 11 years. Cargo specific marginal costs and the degree of economies of scale and scope are calculated up to a port level. Results show that liquid bulk and non-containerised general cargo present the lowest and largest marginal cost, respectively. Increasing returns to scale are present in general and for each and every port. A scope analysis indicates that port specialisation is not appropriate from the viewpoint of infrastructure.  相似文献   
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