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In the field of open-pit mines, the demand for cooperative operation of auxiliary operation manned vehicles matching intelligent driving mining trucks has become a new industry hotspot. There are many types of auxiliary operation manned vehicle, and the scene of cooperative operation is also complex and diverse, which make cooperative operation very difficult. This paper studies the core components of the collaborative work management system, and puts forward a design method of the on-board computing display control unit that integrates the on-board computing control function and human-computer interaction processing function. This method adopts the modular design method to design the system architecture, system software and hardware architecture and application software architecture of the on-board computer display control unit. According to the characteristics of collaborative work applications, three typical application software interface automatic adaptation schemes are proposed by using the human-computer interaction design method. This method adopts the scheme of covering all cooperative auxiliary operation vehicles with the same set of software and hardware, which can reduce the cost of development and maintenance, and has a good engineering application prospect. The on-board computing display control unit designed according to this method has been applied in an open-pit coal mine, and has realized the loading of various types of vehicles. During the application process, all the cooperative vehicles assist the whole process operation of the unmanned mine trucks as a whole, with smooth cooperation and stable equipment operation.

To solve the poor performance or even failure of the cross-spectrum (CS) method in hydroacoustic weak-target passive velocimetry, a sparse Bayesian learning cross-spectrum method (SBL-CS), combining phase compensation with sparse Bayesian learning (SBL) is proposed in this paper. Firstly, the cross-correlation sound intensity is taken as the observation quantity and compensates for each frequency point of the cross-spectrum, which enables the alignment of cross-spectrum results at different frequencies. Then, the inter-correlation sound intensity of all frequencies is fused in the iterative estimation of the target velocity, verifying the proposed method's ability to suppress the background noise when performing multi-frequency processing. The simulation results show that the proposed method is still effective in estimating the target velocity when the CS method fails and that the performance of the proposed method is better than the CS method with a decrease in SNR. As verified using the SWellEx-96 sea trial dataset, the RMSE of the proposed method for surface vessel speed measurement is 0.3545 m/s, which is 46.1% less than the traditional CS method, proving the feasibility and effectiveness of the proposed SBL-CS method for the estimation of the radial speed of a passive target. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces have been used in various fields of engineering due to their resistance to corrosion and fouling and their ability to control fluid movement. Traditionally, superhydrophobic surfaces are fabricated via chemical methods of changing the surface energy or mechanical methods of controlling the surface topology. Many of the conventional mechanical methods use a top-to-bottom scheme to control the surface topolopy. Here, we develop a novel fabrication method of superhydrophobic substrates using a bottom-to-top scheme via polymer OSTE, which is a prototyping polymer material developed for the fabrication of microchips due to its superior photocuring ability, mechanical properties, and surface modification ability. We fabricate a superhydrophobic substrate by OSTE–OSTE micro mushroom forest via a two-step lithography process. At first, we fabricate an OSTE pillar forest as the mushroom stems; then, we fabricate the mushroom heads via backside lithography with diffused UV light. Such topology and surface properties of OSTE render these structures superhydrophobic, with water droplets reaching a contact angle of 152.9 ± 0.2°, a sliding angle of 4.1°, and a contact angle hysteresis of less than 0.5°. These characteristics indicate the promising potential of this substrate for superhydrophobic applications. [ABSTRACT FROM AUTHOR]

Printed circuit heat exchanger (PCHE) is a promising candidate of coolers used for SCO2 Brayton cycle. The thermal-hydraulic performance of SCO2 in a PCHE depends on the PCHE structure as well as the operating conditions of SCO2 due to its dramatic variation of thermal physical properties near the pseudo-critical point. This work experimentally investigated the thermal-hydraulic characteristics of zigzag-channel PCHEs between SCO2 and water at pressures that ranged from 8.0 to 11.0 MPa. Results showed that increasing the flow rate of SCO2 might affect the PCHE more pronouncedly in comparison with changing the flow rate of water, indicating that the major convective thermal resistance is on the SCO2 side. When increasing the operating pressure from 8.0 MPa to 11.0 MPa, the Nusselt numbers of PCHEs with zigzag angles of 0°, 15°, and 25° averagely decrease by 63.3%, 62.1%, and 54.0%, and the friction factors averagely decrease by 28.6%, 27.4%, and 21.0% respectively. Meanwhile, it is found that the buoyancy force is non-negligible during SCO2 cooling process in PCHEs. In this regard, Nusselt number and friction factor correlations considering the buoyancy effect are proposed with applicable ranges. [ABSTRACT FROM AUTHOR]