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For high-speed trains, out-of-roundness (OOR)/defects on wheel tread with small radius deviation may suffice to give rise to severe damage on both vehicle components and track structure when they run at high speeds. It is thus highly desirable to detect the defects in a timely manner and then conduct wheel re-profiling for the defective wheels. This paper presents a wayside fiber Bragg grating (FBG)-based wheel condition monitoring system which can detect wheel tread defects online during train passage. A defect identification algorithm is developed to identify potential wheel defects with the monitoring data of rail strain response collected by the devised system. In view that minor wheel defects can only generate anomalies with low amplitude compared with the wheel load effect, advanced signal processing methods are needed to extract the defect-sensitive feature from the monitoring data. This paper explores a Bayesian blind source separation (BSS) method to decompose the rail response signal and to obtain the component that contains defect-sensitive features. After that, the potential defects are identified by analyzing anomalies in the time history based on the Chauvenet’s criterion. To verify the proposed defect detection method, a blind test is conducted using a new train equipped with defective wheels. The results show that all the defects are identified and they concur well with offline wheel radius deviation measurement results. Minor defects with a radius deviation of only 0.06 mm are successfully detected.

Tofu cake added with three levels of ethanol was made into silages and fed to four wethers to investigate characteristics of ruminal fermentation.The animals received a basal diet consisting of the second cut Orchardgrass hay and beet pulp (4:1) and either fresh tofu cake (control) or one of silages made of tofu cake added with ethanol at 2%, 4% and 6% levels was also fed so that it account for 20% of the whole ration.Feeding levels were determined based on metabolic body size and were restricted to 85% of voluntary intake levels. 1) The animals fed with tofu cake silages had different ruminal fermentation compared to those in the control.There were positive or negative linear effects of amount of ethanol added to tofu cake silage on ruminal pH, volatile fatty acid (VFA) and other parameters.2) The higher the levels of ethanol added to tofu cake silage the higher the total VFA, acetic, valeric and caproic acid levels and adversely the lower the propionic acid levels.3) The animals fed with tofu cake silages had significantly (P<0.01) higher ratios of propionic acid to acetic acid in the rumen fluid. 4) Rumen fluid taken from the animals fed with tofu cake silages had lower pH and lactic acid than that from the control. 5) Although there were no apparent increase in pH, total VFA level or any particular VFA levels in the rumen for the amount of tofu cake fed to the animals in this study, further investigations for optimum feeding levels of tofu cake are needed.

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