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Highlights • An active heat sink with agitators, synthetic jets, and micro pin fins is introduced. • The active heat sink is a more efficient method than traditional fan-assisted systems. • The active heat sink reduced a thermal resistance by 48% from the baseline condition. • The micro pin fins are most efficient in reducing the system thermal resistance. Abstract Air-cooled heat sinks are widely used for electronics cooling. Active and passive cooling components can be added to enhance the performance of the air-cooled heat sinks. In this paper, piezoelectric translational agitators and synthetic jets are integrated as active cooling components while micro pin fins are adopted as a passive cooling scheme. The heat transfer performance of the active heat sink system that combines these active and passive cooling components along with a suction fan is experimentally investigated. The piezoelectric translational agitators installed within cooling channels are operating at 222 Hz ∼ 820 Hz with a peak-to-peak displacement of 1.0 mm ∼ 1.4 mm, depending on the attached carbon fiber blade type. The piezoelectric synthetic jet array provides impingement flow into the cooling channels with an inclined configuration, that has been successfully integrated into the system without interference with other components by using a wedge platform. The jet operates at 720 Hz with the jet velocity of up to 39 m/s. Micro pin fins are fabricated onto both surfaces of each heat sink channel walls by a double-sided microfabrication technique. They have diameter, height, and spacing of 500 μm, 250 μm, and 1500 μm, respectively. The experimental results indicate that the micro pin fins are most efficient among the employed active and passive cooling components, reducing thermal resistance up to 38%, compared to plain heat sink performance. The piezoelectric translational agitator reduces system thermal resistance by 22%, compared to the non-agitated condition, at the same through-flow rate. The synthetic jet shows weaker cooling capability in the setting tested, compared to enhancement by the agitator plates or pin fins. The active heat sink with the micro pin fins, agitators, and jets provides a thermal resistance of 0.064 °C/W at 70 CFM (33 L/sec) through-flow of air, about a 48% reduction from that of the non-agitated, plain heat sink under the same operating conditions. The results demonstrate how more effective the active heat sink system is compared to traditional air-cooled heat sinks. [ABSTRACT FROM AUTHOR]

• A real-time hybrid testing based on shaking table and actuator is proposed for cable tray system. • The proposed method is validated by numerical simulations. • The proposed method is experimentally validated by one cable tray system. For precisely disclosing the seismic performance of cable tray systems, one novel Real-Time Hybrid Testing based on Shaking Table and Actuator (RTHT-STA) is proposed in this paper. In the proposed method, one shaking table is used to simulate the ground motion, and one servo-hydraulic actuator controlled with displacement mode is set up on the shaking table for truly simulating the transverse shear boundary conditions between the numerical substructure and the experimental substructure of cable tray systems. The advantage of the proposed method is accurately realizing the loading requirements of high-precision large deformation on cable tray systems. The effectiveness and accuracy of the proposed method are validated by numerical simulations and experimental tests. The experimental results show that the real-time hybrid testing system is stable and reliable. The correlation coefficients between the results of the proposed method and those of the traditional shaking table tests are higher up to 91.78%. The results indicate the effectiveness and the high accuracy of the proposed RTHT-STA for cable tray systems. The RTHT-STA provides an economical and precise investigation strategy for disclosing the seismic performance of cable tray systems and may have broad application prospects in the field of communication engineering and civil engineering. [ABSTRACT FROM AUTHOR]