动力集中和动力分散的特点

从运用、市场和列车型式的发展趋势等方面 ,分析了动力集中和动力分散的特点。特别阐述了利用寿命周期成本 (L CC) ,来比较这 2种方式列车的优劣     

Modelling car availability,modal split and trip distribution by Monte-Carlo simulation: A short way to integrated models

The model used a Monte-Carlo algorithm to simulate modal split and trip distribution as an interconnected decision process at the individual level. Using census data, the individuals of a planning region are classified into situation groups, which represent significantly different decision situations with respect to socio-demographic position and territorial location. According to the theoretical framework, which emphasises mobility constraints instead of preferences, household structure and sex (time budget and car availability constraints) and work place characteristics (location constraints) are the key variables. For each situation group, decision profiles are empirically determined; these describe car availability, travel time constraints and work place distribution. Modal split and trip distribution are simulated as an interconnected individual decision process, which is stochastically determined by the location of the individual and the decision profile of his situation group.The algorithm is very sensitive and flexible and extremely well suited to electronic processing. An extended and modified version is currently being used in the preparation of regional transporation plans for several German city regions.     

The impact of exceptionally warm summer inflow events on the environmental conditions in the Bornholm Basin

In late summer 2002 and 2003, exceptionally warm inflow events of saline water were observed in the Baltic. These warm saline waters were embedded in the halocline of the Bornholm Basin and caused a strong anomaly of the seasonal temperature cycle. The temperature in October 2002 was the highest ever observed in the halocline of the Bornholm Basin.Although the oxygen content of the inflowing water was only about 1.5 ml l^− 1 at the Darss Sill, it caused a moderate ventilation of the halocline in the Bornholm Basin. On the way through the Arkona Basin, the entrainment of ambient water increased the oxygen content of the inflowing saline water masses.Warm summer inflows were rare events in the last 50 years, but their frequency has increased since 1990. This is likely caused by climate change. The analysis of a 50-year time series of hydrographic parameters reveals significant changes of the thermal regime around the year 1988. The winter surface and intermediate water temperatures of the Bornholm Basin increased by about 1 °C. Also, the duration of warm water in the surface layer was prolonged after 1988. A high correlation between the minimum intermediate winter water temperatures and the NAO winter index was found.Since temperature is a key parameter for many biological processes various responses of the ecosystem to the change in hydrographic conditions could be expected. Possible biological implications of the warm inflow events for the ecosystem are discussed.     

信息技术在海事行业的发展趋势

2009年5月10日-12日,第八届"计算机和信息技术在海事行业中的应用(COMPIT)"国际会议在匈牙利首都布达佩斯举行.自2000年举办首届会议以来,COMPIT已成为海事行业信息技术领域的重要会议,汇聚了众多软件开发商和用户.会议内容涵盖了船舶的生命周期,以及海上设施与设备,从设计到营运.     

Fully three-dimensional ship seakeeping computations with a surge-corrected Rankine panel method

A 3-d seakeeping code uses first-order Rankine panels with special numerical integration on the ship's hull and Rankine point source clusters above the free surface. The code computes the motions of the ship in regular waves of small height (linearized). The steady flow is captured without simplification by solving the fully nonlinear wave-resistance problem first. A special treatment of the surge motion considers the influence of periodic quantities on thrust and resistance, and improves surge motion predictions. Radiation and open-boundary conditions are enforced by staggered grids. Results for the ITTC standard test case S-175 containership agree well with experiments except for very long waves. The importance of capturing the three-dimensional steady flow contributions is also demonstrated.     

创新的马勒小型化发动机

降低二氧化碳排放物,以及越来越严厉的其他排放法规,是开发未来内燃机最重要的挑战。马勒具有众多系统开发专项技术,并且有80多年成功开发和研制内燃机部件和系统的经验。现在马勒在开发具有创新意义的小型化发动机,来证明其在最新发动机技术领域的能力。