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For the battery pack’s limited remaining power, two energy-aware ecological driving problems are discussed. A real-time energy-aware ecological driving control strategy is proposed to optimize energy consumption and meet the ECO driving demand. First, the vehicle longitudinal driving dynamics model and energy consumption model are established. Then, the optimal control problem is constructed with the maximum driving distance and the shortest driving time as the objective functions, respectively. With the multinomial Radau pseudo-spectral method, the optimization results of residual power, vehicle speed, and acceleration are obtained. The results show that in the case of in-vehicle driving the remaining power of the battery pack can be sensed in real-time, and the driving of intelligent electric vehicles can be planned in real-time to realize the most ecological driving with the largest driving distance and shortest driving time. The energy consumptions of vehicles, traveling at the same distance, are compared. The consumption obtained through optimization, is 26% less than the consumption of the vehicle that has not been optimized. The results show that the optimization process has certain advantages. In the future, as one of intelligent vehicles’ autonomous driving control strategies, the results have guiding and practical significance.

Abstract. Low strain dynamic testing is an important nondestructive testing method in the engineering. However, the pile foundation material is usually assumed as having a uniform elastic modulus in low strain simulations. In this paper, we consider the elastic modulus of concrete as having an inhomogeneous elastic modulus that is described by the Weibull distribution model. An explicit algorithm was adopted in order to solve the model. The finite element method (FEM) was used to simulate the low strain dynamic test of a 3D pile. The response velocity characteristics of different shape parameters were obtained using this method, and the Daubechies wavelet transform was used to analyze the characteristics of the wavelet modulus. The result shows that simulation response velocity has a correlation with the different homogeneity of the elastic modulus.

As the largest organ in the human body, the skin provides the important sensory channel for humans to receive external stimulations based on touch. By the information perceived through touch, people can feel and guess the properties of objects, like weight, temperature, textures, and motion, etc. In fact, those properties are nerve stimuli to our brain received by different kinds of receptors in the skin. Mechanical, electrical, and thermal stimuli can stimulate these receptors and cause different information to be conveyed through the nerves. Technologies for actuators to provide mechanical, electrical or thermal stimuli have been developed. These include static or vibrational actuation, electrostatic stimulation, focused ultrasound, and more. Smart materials, such as piezoelectric materials, carbon nanotubes, and shape memory alloys, play important roles in providing actuation for tactile sensation. This paper aims to review the background biological knowledge of human tactile sensing, to give an understanding of how we sense and interact with the world through the sense of touch, as well as the conventional and state-of-the-art technologies of tactile actuators for tactile feedback delivery.

In order to comprehensively evaluate the properties of rock-filled concrete (RFC) with the strength of C15, lab experimental test and in-situ test are applied to explore the mechanical, hydraulic, ultrasonic characteristics of RFC in Hantang reservoir dam. Four types of defects within RFC are shown from the appearance of borehole cores specimens: (1) large sized voids existing in interfacial transition zone (ITZ) between self-compacting concrete (SCC) and rock block (RB); (2) bad cohesion in ITZ; (3) joints within rock block; (4) voids within SCC. For hydraulic aspects, the average porosity of RFC is 14.10%; the permeability rate of RFC ranges from 2.41 Lu to 10.41 Lu, with the average of 11.32 Lu, occasionally more than 25.52 Lu due to interconnected defects. For ultrasonic aspects, the ultrasonic velocity of RFC conforms to lognormal distribution, with the average of 2993.3 m/s and standard deviation of 650.5 m/s. For mechanical aspects, the average cubic compressive strength of RFC is 22.55 Mpa, with the standard deviation of 4.09 Mp. Thus the data shows a relatively great dispersion due to uneven distribution of some defects in RFC, which deteriorate the quality of RFC. Through the experimental investigation, it is shown that the quality of massive RFC in the Hantang dam is obviously non-homogeneous, mainly influenced by construction technology.

To clarify the factors affecting the stability of deep-buried hydraulic tunnels containing pore water, the elastoplastic theory and the Mogi-Coulomb strength criterion were used to derive the analytical solutions of stress on the surrounding rock-lining structure, tunnel wall displacement, and plastic zone radius in surrounding rock under different operating conditions. During this process, the seepage effect and surrounding rock-lining interaction were considered. The influencing rules of seepage action, intermediate principal stress coefficient, lining permeability coefficient, and lining thickness on the stability of the surrounding rock-lining structure were investigated in depth. The results show that the seepage effect significantly changed the stress distributions in the lining structure and surrounding rock, reduced the bearing reaction force, and lowered the tunnel stability. The bearing reaction force was decreased considerably from the intermediate principal stress, and the plastic zone radius in the surrounding rock and the tunnel wall displacement was obviously reduced. Moreover, the bearing reaction force was reduced, and the plastic zone radius in the surrounding rock and the tunnel wall displacement was increased with the decrease of the lining permeability coefficient. With increasing the lining thickness, the bearing reaction force was enhanced, and an apparent restriction on the development of plastic zone in the surrounding rock appeared at the beginning, but the restriction effect weakened subsequently. This research can theoretically provide references for analyzing the stability of hydraulic tunnels containing pore water.

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Wetlands are vital ecosystems in the Tibetan Plateau that play a crucial role in water conservation, flood storage, and biodiversity maintenance. They are sensitive to climate change and typically have high ecological and environmental quality levels due to minimal human disturbance. This study aimed to quantify landscape pattern changes within the Nagqu Hangcuo National Wetland Park (NNWP) and identify the impact of climate on wetland change. Using remote sensing data from six periods (1990, 1995, 2000, 2005, 2010, and 2015), dynamic change analysis, landscape pattern analysis, and correlation analysis were employed to determine the evolutionary features of the wetland landscape and explore their relationship with climatic factors. The results showed that the total wetland area increased from 15.11 km2 in 1990 to 15.23 km2 in 2015. The meadow area increased the most among landscape types, primarily converted from swamps. Over 25 years, the fragmentation of the NNWP’s landscape increased while diversity decreased and its shape became more complex. Meadows were more sensitive to climatic factors than other landscape types, with correlation coefficients between wetland separation and sunshine duration being more significant than other climatic factors. Therefore, it is imperative to monitor landscape pattern changes and the effects of climate change to better protect wetland parks through long-term planning, suitable mechanisms, and advanced technology.