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1.
ABSTRACTDue to the constant risk of piracy and terrorist attacks which cause disturbances within international shipping of goods, barriers to the adoption of maritime security guidelines (MSGs) at European ports have become prevalent. In this paper, a conceptual framework was created to explore the perceived barriers that prevent compliance with MSGs. To verify the conceptual framework, empirical data were collected using a mixed-methods approach, which was comprised of interviews with national experts and a survey of 47% of Swedish ports involved in the shipping of goods. According to the presented framework, the perceived barriers of Swedish ports to compliance with MSGs were linked to collaborations within the Swedish Maritime Security stakeholder network, available resources and educational knowledge about security culture. In addition, the perceived barriers of smaller ports were linked to the adaptation to MSGs at different levels and the absence of specific tools of maritime security management. Due to an increased interest in international shipping of goods, this paper is currently one of few that addresses the barriers to compliance with MSGs. Moreover, the paper presents a general conceptual framework, novel managerial implications and recommendations for future research. 相似文献
2.
This paper presents the results of an investigation into temporal determinants of maritime accidents based on a data-set obtained from the proceedings of formal inquiries in the former German Democratic Republic (GDR). The results show that there is no statistically significant outcome between the probability for an accident and the time of watch. Thus the results do not confirm previous studies, which reported significant time of day effects.The outcome of this study indicates that marine inquiries can provide useful data for an analysis of underlying causes of maritime accidents. It is suggested that accident inquiries should be extended into the area of watch systems employed and should record the hours of work and of rest of the officers on the watch involved in a maritime accident. 相似文献
3.
Synthesis of a Model-Based Tire Slip Controller 总被引:3,自引:0,他引:3
Stefan Solyom Anders Rantzer Jens LÜ demann 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2004,41(6):475-499
The Anti-lock Braking System is an important component of the steering system in a modern car. In the latest generation of brake-by-wire systems, the performance requirements on the ABS are much higher. The controllers have to be able to maintain a specified tire slip for each wheel during braking. The authors propose a design model and based on that a gain-scheduled controller that regulates the tire-slip. Simulation and test results are presented. 相似文献
4.
Transportation - We show how data collected from a GPS device can be incorporated in motor insurance ratemaking. The calculation of premium rates based upon driver behaviour represents an... 相似文献
5.
Bondemark Anders Andersson Henrik Wretstrand Anders Brundell-Freij Karin 《Transportation》2021,48(5):2709-2734
Transportation - One of the reasons to subsidise public transport is to improve the mobility of low-income groups by providing affordable public transport; however, the literature describes a... 相似文献
6.
ABSTRACTTo avoid propagation of delays in dense railway timetables, it is important to ensure robustness. One strategy to improve robustness is to provide adequate amount of buffer times between trains. This study concerns how “scheduled minimum headways” should be determined in order to improve robustness in timetables. Scheduled minimum headways include technical minimum headway plus some buffer time. We propose a strategy to be implemented in timetables at the final stages of planning and prior to the operations. The main contributions of this study are 1) to propose a strategy where the size of the scheduled minimum headways is dependent on trains' travel times instead of a fixed-sized time slot and it is called “travel time dependent scheduled minimum headways” or TTDSMH, 2) to evaluate the effects of the new strategy on heterogeneity, speed, and the number of trains in timetables, 3) to show that a simple strategy can improve robustness without imposing major changes in timetables. The strategy is implemented in an Mixed Integer Linear Programming framework for timetabling and tested for some problem instances from Sweden. Results show that TTDSMH can improve robustness. The proposed strategy can be applied in intelligent transportation tools for railway timetabling. 相似文献
7.
Svein Ivar Sagatun Finn Gunnar Nielsen Erling Handal Nils Veland 《Journal of Marine Science and Technology》1999,4(2):68-75
A method for measuring mooring line tension is proposed based on observation of the natural frequencies of the mooring line
segment between the winch and the fairlead. The anchor line tension is observed through the string equation where an analytical
expression for the line's eigen-frequencies is obtained. The tension is observed on line by utilizing a nonparametric system
identification approach in which the peaks of a maximum entropy spectrum of the transverse acceleration measures of the vibrating
string are automatically identified. The method is verified against full-scale data from the Troll B floating concrete oil
production platform operating in the North Sea.
Received for publication on Feb. 24, 1999; accepted on July 26, 1999 相似文献
8.
Svein Ivar Sagatun Kjell Herfjord Finn Gunnar Nielsen Erling Huse 《Journal of Marine Science and Technology》1999,4(2):58-67
One of the main challenges in estimating impact energy in collisions between marine risers is the assessment of the riser
mass involved in the collision. Evidently the entire riser mass does not contribute to the collision. Hence, the question
is: What is the equivalent riser mass which contributes to the impact energy? This article presents three different ways of
estimating the riser mass participating in the collision energy. The first method is strictly experimental. The second method
uses a numerical experiment together with system identification techniques. The third method is a strictly analytical method,
which results in an asymptotically upper bounded estimate of the participating mass. Two risers are examined as case studies.
The first riser is a 1 : 100 model scale riser used in collision experiments carried out at Marintek's towing tank in Trondheim,
Norway. The second case uses a real world riser in use on the Troll B oil production platform operating in the North Sea.
The proposed methods yield consistent and comparable results.
Received for publication on Feb. 1, 1999; accepted on July 8, 1999 相似文献
9.
Anders Karlström Joel P. Franklin 《Transportation Research Part A: Policy and Practice》2009,43(3):283-296
This paper assesses the horizontal and vertical equity effects of the Stockholm Trial with Congestion Pricing for morning commuters, in terms of both travel behavioral adjustments and welfare effects, as a result of the toll’s direct effects and the behavioral adjustments. We consider specifically two behavioral adjustments: mode choice and departure time choice. Initial car drivers crossing the toll cordon had a 15 percentage-points higher rate of switching to public transit as compared with those not crossing the cordon. We also find some evidence of peak spreading, in particular toward a later departure time, as a result of the charging scheme, but most people choose a departure time within 15 min both before and during the trial. In the welfare analysis, we found no clear pattern of increasing burden by either increasing income or decreasing income, and the increase in the Gini Coefficient was insignificant. We also found no significant difference in either the mode-switching behavior or the average welfare effect for women versus for men. 相似文献
10.
Jens C. O. Nielsen Roger Lund n Anders Johansson Tore Vernersson 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2003,40(1):3-54
Summary High-frequency train-track interaction and mechanisms of wheel/rail wear that is non-uniform in magnitude around/along the running surface are surveyed. Causes, consequences and suggested remedies to relieve the problems are discussed for three types of irregular wheel/rail wear: (1) short-pitch rail corrugation on tangent tracks and large radius curves, (2) wheel corrugation as caused by tread braking, and (3) wheel polygonalisation. The state-of-the-art in modelling of dynamic train-track interaction in conjunction with prediction of irregular wear is reviewed. 相似文献