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The liner layers of natural sand-clay mixtures are extensively used in a range of geotechnical and geoenvironmental projects. In many of these projects, these layers are exposed to dynamic loads or waves due to natural seismic earthquakes or due to human activities, such as machine vibrations, traffic repeated loads, and other impact loads. The permeability of liners is a key property and should be adequately designed to sustain these loads during their lifetime of serviceability. This study sought to evaluate the possible effects of dynamic loads on the efficiency of two different sand-expansive clay (SCL) liners during their lifetime. This was achieved through experimental tests for two series; the first series was subjected to dynamic loads (up to 500 cycles) using the triaxial dynamic system and then tested for permeability for a long period of up to 100 days. The permeability results were compared with the second series tested without being subject to dynamic loads. The dynamic properties for both liners, such as the shear modulus (G), damping ratio (D), and degradation index (δ) were determined and discussed. The results indicated that both materials showed significant degradation with an increase in cycles of dynamic loads; most of the degradation took place during the first 100 cycles. In consequence, the dynamic loads induced a significant effect on the performance of the liners during their lifetime (reducing the permeability by more than six times). These effects were time-dependent and should be taken into account during the design phases.

This paper presents a prototype of automated gate powered by automatic license plate recognition system. The prototype is an embedded system running a Raspbian operating system on the Raspberry Pi microcontroller. A USB camera, LCD, and a servo motor are attached to capture an image of a vehicle, to display information and to represent an automated gate respectively. OpenALPR library is used to perform the license plate recognition, while the complete automated gate system, which is used performing image capturing, license plate recognition, and authentication to gate operation is built using the Node-RED software. As a result, the system successfully recognizes the vehicle number plate and categorize them. All information about the vehicle are displayed on the LCD, and if the vehicle is authorized, the gate operated accordingly. The analysis results show that the system is able to achieve a recognition rate of 87.50–90.90% on images with a specified height and angle.