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The electro-thermal method is most commonly used for wind turbine anti-/de-icing. The upmost drawback of such systems is the high power consumption. In the present study, we proposed to use a durable slippery liquid-infused porous surface (SLIPS) to effectively reduce the power requirement of the heating element during the anti-/de-icing process. The explorative study was conducted in the Icing Research Tunnel at Iowa State University (ISU-IRT) with a DU91-W2-250 wind turbine blade model exposed under severe icing conditions. During the experiments, while a high-speed imaging system was used to record the dynamic ice accretion process, an infrared (IR) thermal imaging system was also utilized to achieve the simultaneous surface temperature measurements over the test model.

Intelligent sweeper vehicle is gradually applied to human life, in which the accuracy of garbage identification and classification can improve cleaning efficiency and save labor cost. Although Deep Learning has made significant progress in computer vision and the application of semantic network segmentation can improve waste identification rate and classification accuracy. Due to the loss of some spatial information during the convolution process, coupled with the lack of specific datasets for garbage identification, the training of the network and the improvement of recognition and classification accuracy are affected. Based on the Unet algorithm, in this paper we adjust the number of input and output channels in the convolutional layer to improve the speed during the feature extraction part. In addition, manually generated datasets are used to greatly improve the robustness of the model.

In the present study, an experimental investigation was conducted to characterize a hot-air-based anti-/de-icing system for the icing protection of aero-engine inlet guide vanes(IGVs). The experimental study was conducted in a unique icing research tunnel available at Iowa State University (i.e., ISU-IRT). A hollowed IGV model embedded with U-shaped hot-air flowing conduit was designed and manufactured for the experimental investigations. During the experiments, while a high-speed imaging system was used to record the dynamic ice accretion or anti-/de-icing process over the surface of the IGV model for the test cases without and with the hot-air supply system being turned on, the corresponding surface temperature distributions on the IGV model were measured quantitatively by using a row of embedded thermocouples.

An experimental study was conducted to investigate the dynamic ice accretion processes on bridge cables with different surface modifications (i.e., 1. Standard plain, 2. Pattern-indented surface, and 3. helical fillets). The icing experiments were performed in the unique Icing Research Tunnel available at Iowa State University (i.e., ISU-IRT). In order to reveal the transient ice accretion processes and the associated aerodynamic loadings on the different cable models under the different icing conditions (i.e., rime vs. glaze), while a high-speed imaging system was used to capture the transient details of the surface water transport and ice accretion over the cable surfaces, a high-accuracy dual-transducer force measurement system was also utilized to measure the aerodynamic loadings acting on the ice accreting cable models.

Recently developed dielectric barrier discharge (DBD) plasma-based anti-icing systems have shown great potential for aircraft icing mitigation. In the present study, the ice accretion experiments were performed on to evaluate the effects of different layouts of DBD plasma actuators on their anti-/de-icing performances for aircraft icing mitigations. An array of DBD plasma actuators were designed and embedded on the surface of a NACA0012 airfoil/wing model in different layout configurations (i.e., different alignment directions of the plasm actuators (e.g., spanwise vs. streamwise), width of the exposed electrodes and the gap between the electrodes) for the experimental study. The experimental study was carried out in the Icing Research Tunnel available at Iowa State University (i.e., ISUIRT).

An explorative study was performed to demonstrate the feasibility of using a novel hybrid anti-/de-icing strategy for aircraft icing mitigation. The hybrid method was developed by combining the electro-thermal heating mechanism and specialized surfaces/coatings with different wettabilities. While an electrical film heater was utilized to provide thermal energy around the leading edge of a NACA0012 airfoil model, two different coating strategies, (i.e., (a). Superhydrophobic coating covering the entire airfoil surface to increase droplets bounce-off and accelerate surface water runback vs. (b). super-hydrophilic coating at the leading edge to increase evaporation area + superhydrophobic coating in downstream to prevent runback refreezing) were proposed and evaluated aiming at maximizing the anti-/de-icing efficiency of the hybrid method.

A brake pedal stroke simulator for Electro-hydraulic Braking System (EHBS) was developed to ensure the comfort braking pedal feel for the brake-by-wire system. An EHBS with an integrated master cylinder was proposed, and a composite brake pedal stroke simulator was designed for the EHBS, which was comprised of two inline springs and a third parallel one. A normally closed solenoid valve was used to connect the master cylinder booster chamber and the stroke simulator. The suitable brake pedal stroke was achieved by three stages of these springs' compression, whereas the solenoid valve was shutdown to enable mechanical control of the service brakes when electrical faults appeared.

Global automotive fuel economy and emissions pressures mean that 48 V hybridisation will become a significant presence in the passenger car market. The complexity of powertrain solutions is increasing in order to further improve fuel economy for hybrid vehicles and maintain robust emissions performance. However, this results in complex interactions between technologies which are difficult to identify through traditional development approaches, resulting in sub-optimal solutions for either vehicle attributes or cost. The results presented in this paper are from a simulation programme focussed on the optimisation of various advanced powertrain technologies on 48 V hybrid vehicle platforms. The technologies assessed include an electrically heated catalyst, an insulated turbocharger, an electric water pump and a thermal management module.

Accurate quantification of 3D shapes of the complex ice structures accreted on wind turbine blades is highly desirable to develop ice prediction models for more accurate prediction of the aerodynamic performance degradation and power reduction due to the ice accretion on wind turbine blades. In the present study, an experimental investigation was conducted to quantitatively characterize the 3D shapes of the ice structures accreted over a DU91-W2-250 wind turbine airfoil model in the Icing Research Tunnel available at Iowa State University (ISU-IRT). A glaze icing condition and a rime icing condition that wind turbines usually experience in winter were duplicated by using ISU-IRT. A high-resolution non-intrusive 3D scanning system was used to make detailed 3D-shape measurements to quantify the complicated ice structures accreted on the wind turbine airfoil model as a function of the ice accretion time.

The commercial vehicle is widely used in the overland transport. A prediction is given on the 9th annual China automotive industry forum that the number of the global commercial vehicles will reach eight million by the year of 2016. However, since the distance between its gravity centre and the ground is larger than that of the passenger vehicle, considering its comparatively short wheelbase, the rollover accident, which is fatal to the drivers and always makes enormous loss of merchandises, easily occurs in the case of commercial vehicles. As the number of the commercial vehicle is increasing fast, the accidents will occur more frequently, the losses will be increasingly enormous. To solve the problem, many researches about rollover early warning systems have been done. In most cases, it is assumed that the references of the vehicle are given.

Turbulent jet ignition (TJI) combustion using pre-chamber ignition can accelerate the combustion speed in the cylinder and has garnered growing interest in recent years. However, it is complicated for the optimization of the pre-chamber structure and combustion system. This study investigated the effects of the pre-chamber structure and the intake ports on the combustion characteristics of a gasoline engine through CFD simulation. Spark ignition (SI) combustion simulation was also conducted for comparison. The results showed that the design of the pre-chamber that causes the jet flame colliding with walls severely worsen the combustion, increasing the knocking intendency, and decrease the thermal efficiency. Compared with SI combustion mode, the TJI combustion mode has the higher heat transfer loss and lower unburned loss. The well-optimized pre-chamber can accelerate the flame propagation with knock suppression.