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In urban vehicular edge computing (VEC) environments, one edge server always serves many task requests in its coverage which results in the resource-constrained problem. To resolve the problem and improve system utilization, we first design a general hierarchical resource management framework based on typical VEC network structures. Following the framework, a specific interacting protocol is also designed for our decision algorithm. Secondly, a greedy bidding-based multi-hop task scheduling decision algorithm is proposed to realize effective task scheduling in resource-constrained VEC environments. In this algorithm, the goal of maximizing system utility is modeled as an optimization problem with the constraints of task deadlines and available computing resources. Then, an auction mechanism named greedy bidding is used to match task requests to edge servers in the case of multiple hops to maximize the system utility. Simulation results show that our proposal can maximize the number of tasks served in resource constrained VEC networks and improve the system utility. [ABSTRACT FROM AUTHOR]

Machines and their components wear down over the course of time. A cause for increased wear can be misalignment issues that stay undetected and cause follow-up damages. Therefore, online monitoring of machines in the industry is of great importance. In this study, the axial misalignment occurring in different dimensions is determined. For this, a time frequency-based Short Time Fourier Transform (STFT) signal processing algorithm is used. The aim of the study is to diagnose faults without using sensors and external data collection systems, but rather by capturing motor current data from the servo motor of the machine. [ABSTRACT FROM AUTHOR]

Reed biochar is used as fuel of direct carbon fuel cells. KCl is the main impurity in raw reeds, which decreases the graphitization degree of biochar obtained from the pyrolysis of reeds, resulting in a high oxidation activity of the biochar. The reed char exhibits a straight hollow tubular structure, bringing about a high electronic conductivity of the anode. A single cell supported by a 610 µm-thick Ce0.8Sm0.2O1.9-carbonate composite electrolyte layer with the reed char as fuel achieves a maximum power density of 378 mW cm-2 at 750°C. The cell with 0.04 g carbon fuel exhibits a discharge current density of 30 mA cm-2 for 3 h. The producing rates of CO and CO2 in the anode under various discharge currents are examined. [ABSTRACT FROM AUTHOR]

La2O3and Sm2O3 are added into Ni-Mo-Ce0.8Sm0.2O1.9 (SDC) as anodes of solid oxide fuel cells with methanol as fuel. The rare earth oxides improve the catalytic oxidation of the fuel, resulting in the decrease of anodic polarization resistance. The single cell with La2O3-Ni-Mo-SDC as the anode and SDC-carbonate composite as the electrolyte exhibits a maximum power density of 765 mW cm-2 at 700°C. The oxides in the anodes also improve the stability of single cells due to the accelerated oxidation of the deposited carbon and the suppression of the deposition of carbon with a high graphitization degree. [ABSTRACT FROM AUTHOR]

MnCo2O4(MCO)-YSZ composite electrodes for solid oxide fuel cells were prepared by alternating electrodeposition cycles of Mn and Co into a composite scaffold of YSZ and by infiltration of Mn and Co salts. Measurements with 10-wt%, 25-wt%, and 40-wt% MCO-YSZ composites showed that good conductivities, greater than 1 S cm-1, could be achieved for 25-wt% and 40-wt% loadings. Also, the ohmic resistances of symmetric cells with 25-wt% and 40-wt% MCO, produced by either electrodeposition or infiltration, were equal to the value calculated for the YSZ electrolyte. However, the non-ohmic losses in MCO-YSZ cells produced by electrodeposition were significantly lower than those produced by infiltration, probably due to the presence of catalytic amounts of Co3O4 in the electrodeposited composites, observed as an impurity phase in XRD. The addition of 5-wt% La0.8Sr0.2FeO3-δ (LSF) to a 40-wt% MCO-YSZ composite further increased electrode performance. [ABSTRACT FROM AUTHOR]