Study on Development of Train Running Diagram Optimization

This article from a whole new perspective on existing studies was classified, from the specific issues addressed by starting on two key issues of recent train scheduling plan: train running diagram and train operation adjustment. Solutions, basic ideas and researches are discussed in detail. Among them, the train working diagram is divided into single and double lane sections and Passenger Train Running Diagram. And the train operation adjustment includes the real-time adjustment, the service of train insert and the conflict prediction. This paper introduces automatic train operation dispatching system in scheduling applications, and discusses the train scheduling problems and the future direction of development.

Seismic safety assessment of trains running on high-speed railway bridges with chloride-induced corroding piers

For the lifetime assessment of the running safety of a train in aggressive environments and earthquake-prone areas,the effects of corrosion on seismic performance must be considered.Research on the running safety of trains,including corrosion damage,is limited,despite the fact that seismic safety assessment of trains on high-speed railway bridges has been extensively examined.In this work,the running safety of a train was evaluated using a time-varying corroded bridge finite-element model established in OpenSees.Two pier types were considered,and three ground-motion types were selected for performing seismic performance evaluations.Subsequently,the seismic response of the corroded bridge-track structure under an earthquake was analyzed.The spectrum intensity was used as the structural response index for the running safety assessment of trains under earthquakes,and the long-term safety of trains on bridges with different pier heights and earthquake types,considering different corroding deterioration,was evaluated.The results indicate that under low-level earthquakes,piers are primarily in a linear elastic state and least influenced by corrosion;whereas under high-level earthquakes,the running safety of trains on a bridge significantly deteriorates after corrosion,particularly for high-pier bridges,mainly because the corroded piers are more likely to yield lower post-yield stiffness.The results of this study suggest that in the seismic safety assessment of trains on corroded bridges,timevarying seismic performance characteristics should be considered.

The Train Runs Faster

Teacher:Why does a train run faster than(比)a car?Pupil:Because it has more wheels(轮子)than a car.

Red Beetroot Juice and Stamina: An Experimental Study

Introduction: Red beet juice is increasingly used in sports to enhance the endurance of athletes. To increase the specific efficiency of red beet juice, the method of its fractionation by ultrafiltration was used for the first time. The purpose of the study was to evaluate the effect of fractionated beetroot juice on the strength and endurance of laboratory rats. Methods: Male Wistar rats (6 groups;n = 10) were used in the study. In addition to the standard chow, some groups of rats 2 h before the exercises received 0.5 ml of native (RBJ) or fractionated (FRBJ) per os. Three groups of animals were trained using a motorized wheel with a gradual speed increase over four weeks: 20 min/day for five days a week. Muscle strength of animals in all groups was measured by electronic dynamometry and the endurance of rats was evaluated once a week using electrical stimulation on a racetrack which moved at a speed of 15 m/min. The test was performed an hour after the ingestion of RBJ or FRBJ. At the end of the experiment, biochemical blood indices were determined. FRBJ was prepared by the original method. Results: Most significant differences in the chemical composition of RBJ and FRBJ were found for glutamic acid, of which the content was 67.2% higher than in native juice. The greatest changes during the experiment were in the mass of the rats’ calf muscles. Regular running exercise caused a 29% increase in muscle mass. The additional increase in m. gastrocnemius was also provided y FRBJ – 12%. The combination of physical activity and the introduction of red beet derivate led to the increase of the calf muscle mass by 121% within a month. Assessing the endurance of animals by frequency of falling from the treadmill, we can conclude that compared with untrained animals, trained rats receiving FRBJ had three times higher levels of endurance. Conclusion: Consumption of FRBJ led to increased muscle strength in rats and the ergogenic effect of the product was significantly higher in combination with physical activity.

Seismic running safety of trains and a new type of seismic-isolation railway structure

Until now,seismic-isolation structures have not yet been applied in the railway field.The reason is that though a seismic-isolation structure can reduce the inertial force to the structure,the energy absorption causes big response displacement on the structure,which adversely effects the running safety of the trains supported by the structure.In this paper,a methodology for seismic running safety assessment is introduced,and a new type of seismic-isolation foundation is proposed,which can convert the seismic response displacement in the lateral direction of track to the longitudinal direction that has a less adverse effect on the running safety of the train.The isolation foundation is composed of FPS(Friction Pendulum System)slider,concave plate and guide ditch.Moreover,through model experiments and 3D numerical simulation,it is verified that the proposed foundation can keep both the effects of the seismic isolation and the running safety of the train during an earthquake.

A Comparison of Three Kinds of Multimodel Ensemble Forecast Techniques Based on the TIGGE Data

Based on the ensemble mean outputs of the ensemble forecasts from the ECMWF （European Centre for Medium-Range Weather Forecasts）, JMA （Japan Meteorological Agency）, NCEP （National Centers for Environmental Prediction）, and UKMO （United Kingdom Met Office） in THORPEX （The Observing System Research and Predictability Experiment） Interactive Grand Global Ensemble （TIGGE） datasets, for the Northern Hemisphere （10~ 87.5~N, 0~ 360~） from i June 2007 to 31 August 2007, this study carried out multimodel ensemble forecasts of surface temperature and 500-hPa geopotential height, temperature and winds up to 168 h by using the bias-removed ensemble mean （BREM）, the multiple linear regression based superensemble （LRSUP）, and the neural network based superensemble （NNSUP） techniques for the forecast period from 8 to 31 August 2007. A running training period is used for BREM and LRSUP ensemble forecast techniques. It is found that BREM and LRSUP, at each grid point, have different optimal lengths of the training period. In general, the optimal training period for BREM is less than 30 days in most areas, while for LRSUP it is about 45 days.