Energy storage is one of the leading problems being faced globally, due to the population explosion in recent times. The conventional energy sources that are available are on the verge of extinction, hence researchers are keen on developing a storage system that will face the upcoming energy needs. Supercapacitors, also known as ultracapacitors or electrochemical capacitors, are advanced energy storage devices characterised by high power density and rapid charge–discharge cycles. Unlike traditional batteries, supercapacitors store energy through electrostatic separation, offering quick energy release and prolonged operational life. They hold exceptional performance in various applications, from portable electronics to electric vehicles, where their ability to deliver bursts of energy efficiently complements or replaces conventional energy storage solutions. Ongoing research focuses on enhancing energy density and overall efficiency, positioning supercapacitors as pivotal components in the evolving landscape of energy storage technologies. A novel electrode material of NiO/CuO/Co3O4/rGO was synthesized which when used as a supercapacitor, the highest value of CS is 873.14 F/g which is achieved for a current density of 1 A/g under with an energy density of 190 Wh/kg and the highest power density of 2.5 kW/kg along with 87.3% retention after 5000 GCD cycles under 1 M KOH.
This study proposes an RCS composite damping device that can achieve seismic reinforcement of existing buildings by dissipating energy by inelastic deformation. A series of experiments assessing the performances of the rubber core pad, hysteretic steel slit damping device, and hybrid RCS damping device were conducted. The results showed that the ratios of the deviations to the mean values satisfied the domestic damping-device conformity condition for the load at maximum device displacement in each direction, at the maximum force and minimum force at zero displacement, as well as the hysteresis curve area. In addition, three analysis models based on load-displacement characteristics were proposed for application to seismic reinforcement design. In addition, the validity of the three proposed models was confirmed, as they simulated the experimental results well. Meanwhile, as the shear deformation of the rubber-core pad increased, the hysteretic behavior of super-elasticity greatly increased the horizontal force of the damping device. Therefore, limiting the allowable displacement during design is deemed to be necessary.
최근에는 다양한 중량의 구조물을 지진으로부터 보호하기 위해 지반으로부터 분리하는 면진장치로써 지반 격리용 받침이 활용된다. 지진의 피해를 저감시키는 설계방법 중에서 면진 설계는 구조물과 지반이 만나는 부분에 면진받침을 사용하는 방식으로 다른 내진/제진 설계 방법과 비교하면 가격대비 효율과 성능이 가장 우수하다. 본 연구에서는 지진 발생 이후 지속적으로 사용 가능한 새로운 개념의 자동복원 면진받침 시스템을 제안하고자 한다. 이러한 면진받침에 대한 성능을 검증하기 위하여 이론 적립 및 설계를 수행하고 실험체를 제작하여 실제 지진 데이터가 적용된 진동대 실험을 수행하였다. 기본특성실험, 면압의존성 실험, 속도의존성 실험, 변위의존성 실험에서 강도하중이 설계 목표치와 유사하였고, 거동 또한 설계값과 유사함을 확인하였고 이를 바탕으로 면진받침의 성능 검증을 분석하였다.
In this study a hybrid energy dissipation device is developed by combining a steel slit damper and linear-slot friction dampers to be used for seismic retrofit of structures. The hybrid damper has an advantage in that friction dampers are activated for small earthquakes or strong wind while slit damper remains elastic, and both friction and slit dampers work simultaneously for strong earthquakes. Cyclic loading tests of the linear-slot friction, slit, and the combined hybrid dampers are carried out to evaluate their seismic energy dissipation capability.