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Various means of extracting road boundary from mobile laser scanning data based on vehicle trajectories have been investigated. Independent of positioning and navigation data, this study estimated the scanner ground track from the spatial distribution of the point cloud as an indicator of road location. We defined a typical edge block consisting of multiple continuous upward fluctuating points by abrupt changes in elevation, upward slope, and road horizontal slope. Subsequently, such edge blocks were searched for on both sides of the estimated track. A pseudo-mileage spacing map was constructed to reflect the variation in spacing between the track and edge blocks over distance, within which road boundary points were detected using a simple linear tracking model. Experimental results demonstrate that the ground trajectory of the extracted scanner forms a smooth and continuous string just on the road; this can serve as the basis for defining edge block and road boundary tracking algorithms. The defined edge block has been experimentally verified as highly accurate and strongly noise resistant, while the boundary tracking algorithm is simple, fast, and independent of the road boundary model used. The correct detection rate of the road boundary in two experimental data is more than 99.2%.

Slope leveling is essential for the successful implementation of ground-mounted centralized photovoltaic (PV) plants, but currently, there is a lack of optimization methods available. To address this issue, a linear programming approach has been proposed to optimize PV slope leveling. This method involves dividing the field into blocks and grids and using hyperbolic paraboloids to simulate the design surface. By programming in MATLAB, the globally optimal solution for PV slope leveling can be calculated. Engineering case studies have demonstrated that this optimization method can achieve significant cut-and-fill volume savings ranging from 58% to 78%, when compared to the traditional segmented plane method. Additionally, the effectiveness of the optimization method improves with larger site areas and more complex terrains. A parameter analysis considering slope ratio, grid size, and block size reveals that grid size has a minimal impact on cut-and-fill volume, while slope ratio and block size have a significant influence. For typical PV projects, the recommended ranges of slope ratio, grid size, and block size are 3–7%, 5–20 m, and 30–50 m, respectively, for slope leveling design. In summary, the proposed linear optimization method provides an optimal slope leveling scheme for ground-mounted centralized PV plants, with convenient operation and fast computation. [ABSTRACT FROM AUTHOR]

To solve the problems of high labor intensity, poor accuracy, and low mixing uniformity in manually adding cementing and plugging materials, an automated metering and adding device for cementing and plugging materials was developed, mainly consisting of silos, belt metering, and hose spiral conveyors. The device was designed with PLC as the core and touch screen as the human-machine interaction interface. The main hardware includes a level gauge, frequency converter, weighing sensor, and variable frequency motor. The device adopts an expert PID control strategy to achieve signal acquisition, logic control, and data communication. Through automated testing of extreme conveying of fiber materials at 3~5 kg/min and sheet-like materials at 10~50 kg/min, the material can be continuously mixed, stirred, and uniformly and stably delivered at any position through a hose type screw conveyor, meeting the requirements for feeding measurement and conveying of two types of materials, including sheet-like materials and fiber materials, in two silos. The results show that its mixing uniformity is good, with less manual participation, stable measurement accuracy, and an error of less than ± 1%; Compared to manual labor, the overall efficiency is two times higher. The research provides a support for automated operation of offshore oil drilling platforms. [ABSTRACT FROM AUTHOR]