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1.
ABSTRACTThe need for improved public transport (PT) ticketing in ever-growing deregulated PT markets has made well-designed integrated ticketing systems a priority area of intervention for PT service providers around the world. Yet, very little practical evidence of its impacts are reported in Sweden and in the world at large. The focus of this study was the impacts of the Movingo integrated ticketing scheme in terms of PT patronage, user satisfaction and the perceived quality of the ticketing set-up. Three travel surveys were conducted along the Stockholm-Uppsala route. Methods including logistic regression and correlated t-tests were used to analyse the samples. The findings suggest that the scheme made rail commuting more attractive resulting in an overall increase of about 24% in ticket sales with 3% – 15% car commuters reporting that they patronised PT services after the project. The scheme also resulted in increased rail commuter satisfaction. The overall perceived quality of the ticketing set-up did not however improve due to interoperability challenges. Service providers’ uncertainty about equitable distribution of revenue among the participating service providers, interoperability challenges and the lack of interest among most of the participating service providers to sell Movingo tickets are some issues to be addressed. 相似文献
2.
The time-series of remote-sensed surface chlorophyll concentration measured by SeaWiFS radiometer from September 1997 to December 2001 and the relevant hydrological and meteorological factors (remote-sensed sea surface temperature, atmospheric precipitation, air temperature and wind stress) in Santa Monica Bay and adjacent waters off southern California were analyzed using wavelet and cross-correlation statistical methods. All parameters exhibited evident seasonal patterns of variation. Wavelet analysis revealed salient long-term variations most evident in air temperature during El Niño 1997–1998 and in wind stress during La Niña 1998–1999. Short-period (<100 days) variations of remote-sensed chlorophyll biomass were mostly typical to spring seasons. Chlorophyll biomass was significantly correlated with air temperature and wind stress: an increase of chlorophyll biomass followed with 5–6-day time lag an increase of wind stress accompanied by a simultaneous decrease of air temperature. The mechanism of these variations was an intensification of phytoplankton growth resulting from the mixing of water column by wind stress and entrainment of nutrients into the euphotic layer. 相似文献
3.
4.
Fluxes of dissolved inorganic carbon in three estuarine systems of the Cantabrian Sea (north of Spain) 总被引:3,自引:1,他引:2
The diffusive and in situ fluxes of dissolved inorganic carbon (DIC) and total alkalinity (TA) have been measured and an estimation has been made of the water–atmosphere fluxes of CO2 in three estuarine systems of the Cantabrian Sea during the spring of 1998. Each of these systems undergoes a different anthropogenic influence. The diffusive fluxes of dissolved inorganic carbon and total alkalinity obtained present values ranging between 0.54–2.65 and 0.0–2.4 mmol m−2 day−1, respectively. These ranges are in agreement with those of other coastal systems. The in situ fluxes are high and extremely variable (35–284 mmol TA m−2 day−1, 43–554 mmol DIC m−2 day−1 and 22–261 mmol dissolved oxygen (DO) m−2 day−1), because the systems studied are very heterogeneous. The values of the ratio of the in situ fluxes of TA and DIC show on average that the rate of dissolution of CaCO3 is 0.37 times that of organic carbon oxidation. Equally, the interval of variation of the relationship between the benthic fluxes of inorganic carbon and oxygen (FDIC/FDO) is very wide (0.3–13.9), which demonstrates the different contributions made by the processes of aerobic and anaerobic degradation of the organic matter, as well as by the dissolution–precipitation of CaCO3. The water–atmosphere fluxes of CO2 present a clear dependence on the salinity. The brackish water of these systems (salinity<20), where maximum fluxes of 989 mmol m−2 day−1 have been estimated, act as a source of CO2 to the atmosphere. The more saline zones of the estuary (salinity>30) act as a sink of CO2, with fluxes between −5 and −10 mmol m−2 day−1. 相似文献
5.
Shape Optimization of Elliptical Road Containers Due to Liquid Load in Steady-State Turning 总被引:1,自引:0,他引:1
G. Popov Research Associate S. Sankar Professor Director T.S. Sankar Professor 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1996,25(3):203-221
A numerical analysis of liquid load in elliptical road containers undergoing a steady-state turning manoeuvre is presented for containers of unrestricted size and for containers of fixed capacity. The liquid load is expressed in terms of the horizontal and vertical forces and the overturning moment created by these forces around the middle bottom point of the container. The moment is obtained by integrating the liquid free-surface equation and using numerical calculation of the resulting expressions. An optimization study with an objective to minimize the peak overturning moment is performed on containers of fixed capacity to identify the optimal height/width ratio of the container. The results of this investigation being of a general nature, i.e. with no restriction for an application, are particularly intended for road tankers under a steady turning manoeuvre, where they can be applied with high degree of accuracy. 相似文献
6.
Despite improvements in road safety over the past several decades, accident rates remain high for young drivers. One accident countermeasure that is expected to improve the safety record of this group is graduated licensing. The philosophy behind this licensing system is that novice drivers, of whom the majority are young, should be restricted to relatively safe driving environments during the initial learning period. Graduated licensing was implemented in the Province of Ontario, Canada in 1994. The objective of this study is to estimate the potential benefits and costs for young drivers associated with two components of the Ontario graduated licensing package: the late-night driving curfew and the high-speed roadway restrictions. Based on accident and travel data for the year 1988, accident-involvement rates per kilometre driven were calculated for different driver groups for various combinations of time of day and roadway speed limit. These rates were then applied to the expected mobility profiles of young drivers affected by graduated licensing. The results of the study support the late-night curfew and suggest that this component of the licensing package should reduce total accident involvements for the affected group by up to 10 percent and fatal accident involvements by up to 24 percent, while reducing their total driving by only four percent. By contrast, the empirical evidence suggest that the high-speed roadway restrictions are likely to increase accident involvements, and thus it is strongly recommended that this component of Ontario's graduated licensing package be changed. 相似文献
7.
HE Tseng J. Asgari D. Hrovat P. van der Jagt A. Cherry S. Neads 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2005,43(3):199-216
In the pursuit of an objective rating on vehicle stability performance, it is always desirable to reduce disturbances and inconsistencies during experimental evaluations, especially the ones introduced by human drivers. This paper presents the development of a steering robot designed for closed-loop steering tasks during evasive manoeuvres. It describes the controller structure and discusses experimental results, in addition to simulation/vehicle model verifications and theoretical control analysis. 相似文献
8.
Basic Analytical Study of Pantograph-catenary System Dynamics 总被引:9,自引:0,他引:9
T.X. Wu M.J. Brennan 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1998,30(6):443-456
For a high speed electrical rail system, good dynamic performance of the pantograph-catenary system is vital for smooth and continuous current collection. It has been known for many years that to achieve this the head of the pantograph should be made as light as possible and the average stiffness of the catenary should be high. These conclusions, however, have been reached by numerical modelling and operational experience. In this paper the pantograph-catenary system is modelled as a time-varying, single degree-of-freedom system to facilitate an analytical investigation of the system dynamics. Although the model is very simple, it allows physical insight into the dynamic behaviour of the system, and because the excitation is parametric it also allows the stability of the system to be investigated. The finite element method is used to determine the catenary characteristics and Floquet theory is used to analyse the behaviour of the coupled system. 相似文献
9.
C. Julian Parker 《WMU Journal of Maritime Affairs》2003,2(2):99-113
This article is in three parts. The first covers the historical development of qualifying associations. The second covers the particular role of maritime institutions that include The Royal Institution of Naval Architects, The Institute of Marine Engineering Science and Technology and The Nautical Institute. The third and final section considers the future for maritime professional associations in the context of international shipping. 相似文献
10.
This paper presents a procedure for the estimation of origin‐destination (O‐D) matrices for a multimodal public transit network. The system consists of a number of favored public transit modes that are obtained from a modal split process in a traditional four‐step transportation model. The demand of each favored mode is assigned to the multimodal network, which is comprised of a set of connected links of different public transit modes. An entropy maximization procedure is proposed to simultaneously estimate the O‐D demand matrices of all favored modes, which are consistent with target data sets such as the boarding counts and line segment flows that are observed directly in the network. A case study of the Hong Kong multimodal transit network is used to demonstrate the effectiveness of the proposed methodology. 相似文献