Vessel traffic service systems: cost-recovery alternatives

This paper investigate cost-recovery alternatives for US federally-operated vessel traffic service (VTS) systems. These include those currently used or have been used by VTS and 'VTS-like' systems and other feasible, but not used herefore, alternatives, a federal trust and a federal VTS user-fee structure. Three federal trust funds exist whose waterway-related earmarked revenues could also be earmarked for VTS systems. A federal VTS user-fee structure while raising revenue to finance VTS systems is not expected to be detrimental to the competitiveness of VTS ports nor to the vessel operators that call if their cost-savings exceed fees paid.     

Diagrammes fondamentaux de zone : estimation et influence de la régulation

Macroscopic fundamental diagrams can model the road traffic at an aggregated scale. This tool allows the evaluation of traffic management strategy at the city level while taking congestion into account. Something the usual macroscopic traffic models can’t do correctly at this scale. However, the calibration of the macroscopic fundamental relation is not easy since lots of factors, from experimental condition to traffic heterogeneities, can alter the shape of the diagram. We show that the use of electromagnetic loops can introduce huge variations in the macroscopic fundamental diagram (MFD) shape. Among the parameters that have considerable impact on the MFD shape, the traffic lights set up can alter it significantly. For a given network, a better knowledge of the link between the traffic light parameters and the MFD shape can help evaluate the network quality of service by computing the average traffic flow speed for the entire network.     

On the feasibility of the optical steering wheel sensor: Modeling and control

This paper discusses the development of a system model for the wireless steering wheel angle sensor and steering wheel system for the evaluation of the steer by wire system in a vehicle dynamic system. The steering wheel sensor is a wireless, contact-less sensor utilizing an optical medium for angle detection. The optical medium is operated based on a photodiode and photo-detector head. A reflecting disc or code-wheel, working similar to a compact disc, is used to reflect the light from the photodiode back to the photo-detector. The beam is reflected based on the content in the reflective disc to measure the relative angle through a micro-controller. The proposed wireless steering sensor and steer by wire system is modeled using the Matlab/Simulink and their performance is investigated to evaluate the steering response, vehicle dynamics, and steering feel of the system. Finally, the feasibility of the proposed system is discussed based on the developed model and simulation results.     

Traffic noise and traffic light control

An optimal control problem of traffic light duration is considered. The traffic noise level is introduced as a state variable in a dynamical optimization problem. A closed loop control system is designed which influences the green duration of the lights according to the equivalent noise level. Real time considerations lead to sub-optimal control implementation. This control policy decreases the noise levels at intensive traffic intersections. The traffic lights adapt their duration according to the noise pollution. Simulation and experimental results are discussed.     

机车车辆设计平台的优越性

不同运营企业小批量订货时高的成本压力迫使制造厂家开发一种机车车辆产品设计平台.这种平台有利于降低生产成本.在预制的模块组件的基础上生产机车车辆.使用模块组件能减少组装时间.     

Measure of productivity loss due to road traffic accidents in Thailand

As one of the top countries with the highest casualties per capita in road traffic accidents, Thailand needs to raise public awareness about the economic loss from road traffic crashes. This paper calculates the value of productivity loss due to road traffic accidents in Thailand in 2017. Extensive data collection and analyses enable to compute income losses over time in case of fatalities, permanent disabilities as well as major and minor injuries. The results reveal that, at the end of 2017, the total amount of productivity loss caused by road traffic accidents alone was approximately 121 billion Baht (45 billions for fatalities, 7 for disabilities, 67.5 for serious injuries and 1.5 for slight injuries), or close to 0.8% of the country's GDP, which is very significant. At-risk age groups are determined in each case and we see that the 16–25 age group is bearing the highest burden in all types of accidents. Future policies can then be targeted to types of casualties and to a specific public.     

Modelling rain effects on risk‐taking behaviours of multi‐user classes in road networks with uncertainty

This paper proposes a new travel time reliability‐based traffic assignment model to investigate the rain effects on risk‐taking behaviours of different road users in networks with day‐to‐day demand fluctuations and variations in travel time. A generalized link travel time function is used to capture the rain effects on vehicle travel times and road conditions. This function is further incorporated into daily demand variations to investigate those travel time variations arising from demand uncertainty and rain condition. In view of these rain effects, road users' perception errors on travel times and risk‐taking behaviours on path choices are incorporated in the proposed model with the use of a logit‐based stochastic user equilibrium framework. This new model is formulated as a variational inequality problem in terms of path flows. A numerical example is used to illustrate the application of the proposed model for assessment of the rain effects on road networks with uncertainty.     

Investigation of the impact of locomotive creep control on wear under changing contact conditions

This paper presents the locomotive traction controller performance with respect to the track wear under different operation conditions. In particular, an investigation into the dynamic response of a locomotive under changing wheel–rail friction conditions is performed with an aim to determine the effect of controller setting on track wear. Simulation using a full-scale longitudinal–vertical locomotive dynamic model shows that the appropriately designed creep threshold, controller, settings can effectively maintain a high tractive effort while avoiding excessive rail damage due to wear, especially during acceleration under low speed.     

利用AGM求解粘弹性地基刚性梁的非线性控制微分方程（英文）

In the present paper a vibrational differential equation governing on a rigid beam on viscoelastic foundation has been investigated. The nonlinear differential equation governing on this vibrating system is solved by a simple and innovative approach, which has been called Akbari-Ganji’s method(AGM). AGM is a very suitable computational process and is usable for solving various nonlinear differential equations. Moreover, using AGM which solving a set of algebraic equations, complicated nonlinear equations can easily be solved without any mathematical operations.Also, the damping ratio and energy lost per cycle for three cycles have been investigated. Furthermore, comparisons have been made between the obtained results by numerical method(Runk45) and AGM. Results showed the high accuracy of AGM. The results also showed that by increasing the amount of initial amplitude of vibration(A), the value of damping ratio will be increased, and the energy lost per cycle decreases by increasing the number of cycle. It is concluded that AGM is a reliable and precise approach for solving differential equations. On the other hand, it is better to say that AGM is able to solve linear and nonlinear differential equations directly in most of the situations. This means that the final solution can be obtained without any dimensionless procedure.Therefore, AGM can be considered as a significant progress in nonlinear sciences.     

Kinetics of Atmospheric Corrosion of Mild Steel in Marine and Rural Environments

In continuation of the extensive studies carried out to update the corrosion map of India, in this study, the degradation of mild steel by air pollutants was studied at 16 different locations from Nago...