Worldscale: what does it actually measure?

Worldscale is the dominant system for setting freight rates in ocean-tanker shipping. Its structure is hampered by administrative rigidity which easily disguises the effects of rate changes and complicates the comparison of rates between vessel size segments. The angle is the charterer's, and the shipowner is left to his/her own devices. The sparseness of spot rates between ports (not regions) and the individuality of flat rates due to varying port charges, make functional generalizations between Worldscale (WS) and time charter equivalents (TCE) hazardous. The publishing of rate parameters for all ship segments and possibly port charges for each port would substantially upgrade the value of the system.     

Train-Track Interaction and Mechanisms of Irregular Wear on Wheel and Rail Surfaces

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.     

Out-of-round railway wheels—a study of wheel polygonalization through simulation of three-dimensional wheel-rail interaction and wear

The objective of this study is to develop a tool for investigation of wheel tread polygonalization with radial irregularities including 1 to 20 wavelengths around the circumference of the wheel. Therefore, an existing multibody system model for simulation of general three-dimensional train-track interaction (accounting for frequencies up to several kHz) is extended with rolling contact mechanics according to FASTSIM. Furthermore, the model is also modified to allow for general wheel-rail profiles. The numerical model uses the concept of an iteration scheme including simulation of dynamic train-track interaction in the time domain coupled with a long-term wear model. A demonstration example including a bogie of a subway train travelling on a straight track is presented. In the example, an initial wheel out-of-roundness (OOR) is applied to the wheels. This irregularity is based on an amplitude spectrum derived from measurements on new wheels. Simulation results show that the most important wavelength-fixing mechanisms of the wheel OOR are (i) the vertical resonance of the coupled train-track system at approximately 40 Hz (the P2 resonance) and (ii) the frequency region including the lowest vertical track antiresonance at 165 Hz, where the dynamic track stiffness is high. Only a straight track is studied, but the model allows for asymmetric train motion on such a track.     

Indirect Effects to Include in Strategic Environmental Assessments of Transport Infrastructure Investments

Abstract

Indirect effects are important considerations when making consequence analyses in general and in strategic environmental assessments in particular of potential transport solutions and infrastructure plans. The primary objective of this paper is to emphasize the need for a deeper understanding of the long‐term system effects of investments in transport infrastructure with a focus on the structuring effects that roads and railways have on society, e.g. altered transport patterns, altered settlement structures and changes in use of the built environment. Special attention is given to the following potential indirect effects: increased total transport volume, increased share of private motorists and truck transport, increased urban sprawl, and increased energy use in buildings. The conditions that determine the power of the effects are discussed and a number of key factors to be considered in transport infrastructure planning, especially in strategic environmental assessments, are suggested. Since many indirect effects emerge over time, an extended time perspective is of essence. Therefore, scenario techniques may be useful when analysing indirect effects in transport planning processes.     

Atmospheric emissions of European SECA shipping: long-term projections

We modeled the projections of the major atmospheric emissions from shipping of the European sulphur emission control area that includes the Baltic Sea, the North Sea, and the English Channel until 2040. Emission projections were calculated separately for every ship on annual basis, and the model took into account traffic growth, fleet renewal, and the forthcoming regulations. The regulation on sulfur content of ship fuels will drastically decrease the emissions of sulfur oxides and particulate matter (PM_2.5). As the regulation on nitrogen oxides (NO _x ) only affects the new diesel engines, the decrease in emissions will be seen parallel with the fleet renewal. Globally internalized limits will turn NO _x emissions to decrease with moderate traffic growth. However, by designating the Baltic Sea and the North Sea as NO _x emission control areas, more drastic decrease would occur. CO₂ emissions will stay almost constant through the studied timeline. Results show that European Commission's CO₂ target for 2050 will not be reached without implementation of market based measures among the North Sea and the Baltic Sea fleets. Results present new information for decision makers to further develop international regulations of shipping especially in the Baltic Sea and the North Sea.     

Worldscale: what does it actually measure?

Worldscale is the dominant system for setting freight rates in ocean-tanker shipping. Its structure is hampered by administrative rigidity which easily disguises the effects of rate changes and complicates the comparison of rates between vessel size segments. The angle is the charterer's, and the shipowner is left to his/her own devices. The sparseness of spot rates between ports (not regions) and the individuality of flat rates due to varying port charges, make functional generalizations between Worldscale (WS) and time charter equivalents (TCE) hazardous. The publishing of rate parameters for all ship segments and possibly port charges for each port would substantially upgrade the value of the system.