Digital printing technologies—including inkjet printing, aerosol jet printing, and electrohydrodynamic jet printing—have emerged as promising strategies for next-generation electronic devices. However, the weak adhesion between printed electrodes and substrates can lead to electrode delamination, thereby compromising device reliability and lifetime. In this study, a dielectric interlayer was introduced to improve the adhesion of silver (Ag) mesh electrodes on glass, polyethersulfone film, and polyimide film substrates. The optimized electrode on PES film achieved an optical transmittance of 83% at 550 nm and line resistance of 0.3 Ω, confirming its suitability as a transparent electrode. The incorporation of the interlayer also enhanced the adhesion and mechanical flexibility across all substrates. Moreover, the printed electrodes exhibited uniform surface heating under an applied bias (≤DC 3 V), and their feasibility as low-power flexible transparent heaters was experimentally demonstrated. These findings present a simple and effective printing strategy for fabricating robust and multifunctional electrodes, offering enormous potential for the realization of future flexible and transparent electronic systems.

The need for energy harvesting in marine environments is gradually increasing owing to the energy limitation of marine robots. To address this problem, a catamaran-type sail drone (CSD), which can harvest marine energies such as wind and solar, was proposed in a previous study. However, it was designed and manufactured without considering the stability, optimal hull-form, and maintenance. To resolve these problems, a CSD with two keels, a performance estimator, V-shape hulls, and modularized components is proposed and its mechanism is developed in this study. To verify the performance of the CSD, the performance estimation using smoothed-particle hydrodynamics (SPH) and the heading control using fuzzy logic controller (FLC) are performed. Simulation results show the attitude stability of the CSD and the experimental results show the straight path of the CSD according to wind conditions. Therefore, the CSD has potential applications as an energy harvesting system.

Recently, research and development on underwater cities have emerged. Hence, research equipment to investigate the characteristics of the seabed is also diversifying. Existing underwater ground survey equipment faces the problem where a large system, high cost, and available ships are limited. Therefore, the FFCPT (Free-Fall Cone Penetration Test) is emerging as a realistic alternative. KIOST in Korea is developing an FFCPT, intending to have a depth of 200m or more and a weight of less than 100㎏. When operating the FFCPT, heavy-load work such as loading on a ship, moving, dropping, and extruding from the seabed is required. It is essential to perform work according to the standard operating procedure (SOP) in consideration of safety. However, there are no studies on SOPs for an FFCPT. Therefore, in this paper, an SOP for an FFCPT was proposed. The result of the total resistance test of the seabed demonstrates the effectiveness of the proposed SOP. Furthermore, we could generalize our work using an FFCPT based on the proposed SOP.