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It is well known that broadband wireless communications (BWC) are necessary for high speed vehicles since passengers need many broadband wireless multimedia services. However, one design challenge is to identify sufficient spectrum resource to support BWC in high speed vehicles. Recently, cognitive radios (CRs) are being considered as a promising technology to solve scarcity problem of spectrum resource. Therefore, we investigate the spectrum resource allocation problem in the CR based high speed vehicle network (CR-HSVN) in this paper. Specifically, we propose a spectrum resource allocation framework, where high speed vehicles could effectively utilize the TV white spaces. Subsequently, we formulate the allocation of spectrum resource as an optimization problem to maximize the available spectrum resources (i.e., TV white spaces) utilized by the CR-HSVN, and investigate the property of the CR-HSVN to reduce the complexity by separation computing method without loss of optimality. Furthermore, we analyze the optimal solution based on branch and bound method, the suboptimal solutions based on single channel and linear programming, respectively. Simulation results show that the proposed framework could offer excellent performances of the spectrum utilization and fairness for the CR-HSVN. Meanwhile, the aggregated interference from vehicles to primary users is constrained. [ABSTRACT FROM PUBLISHER]

Organic solvents and heavy metals are commonly found in industrial wastewater. These compounds may affect or inhibit the activities of microbes involved in biological wastewater treatment process. Monoethanolamine (MEA) is an organic nitrogen containing solvent used in thin-film transistor liquid crystal display industry as stripper. MEA is usually recognized as slowly biodegradable organic solvent. Copper is the most common heavy metals found in swine wastewater. The presence of copper in wastewater can stimulate or inhibit the microbial processes involved in the biological treatment process. In this study, the effects of MEA and copper on the activities of Anammox (anaerobic ammonium oxidation) bacteria were investigated in batch tests. Synthetic wastewaters containing NH4+-N (70 mg L-1) and NO2--N (70 mg L-1) were spiked with either MEA (0 to 500 mg L-1) or copper (0 to 10 mg L-1) at different concentrations and used as media for batch tests. Results of batch tests revealed that MEA, at all concentrations inhibited the activity of Anammox bacteria. The IC50 value of MEA was calculated to be 175 mg L-1. The noncompetitive inhibition model (R2 = 0.81) and linear inhibition model (R2 = 0.87) were fitted well with the experimental data of Anammox inhibition at different MEA concentrations. On the other hand, activity of Anammox bacteria was strongly inhibited by the presence of copper at mixed liquor volatile suspended solids (MLVSS) of < 2000 mg L-1. The IC50 value of copper was calculated to be 4.2 mg L-1. Under the experimental conditions, inhibition of Anammox bacterial activity increased with concentration of copper (1 to 10 mg L-1) and exposure time (3 to 24 h) at lower biomass concentration (< 2000 mg L-1 VSS). However, the specific Anammox activity is positively affected by copper at higher biomass concentration (> 2500 mg L-1 of VSS) and longer exposure time. The inhibition of Anammox bacterial activity by copper was found to be higher at 25 °C compared to at 35 °C. Overall, the results suggested that effect of copper on specific Anammox activity was influenced by concentrations of copper and biomass, exposure time and temperature. [ABSTRACT FROM AUTHOR]