Metamaterials, as artificially engineered structures with unconventional mechanical and acoustic properties, have recently emerged as a transformative platform for enhancing the capabilities of triboelectric nanogenerator (TENG) systems. Since the invention of TENG devices, extensive efforts have been devoted to improving charge density, output stability, and overall performance. Conventional performance optimization strategies mainly rely on device-level improvements such as surface chemistry modification, microstructuring, and nanopatterning. However, limited emphasis has been given to system-level development of smart self-powered intelligent systems. The integration of metamaterials into TENG devices opens a new era by enabling frequency-selective localization, mechanical impedance matching, and controllable deformation pathways. These engineered mechanical structures not only improve energy harvesting efficiency but also introduce new functionalities into the system. This review systematically summarizes recent advances in metamaterial-integrated TENG systems across four major application domains: (i) energy harvesting, (ii) acoustic telecommunication and acoustic-to-electric conversion, (iii) self-powered sensing, and (iv) vibration suppression and monitoring. Overall, the integration of metamaterials into TENG systems will pave the way for next-generation sustainable, intelligent, self-powered devices with diverse functionalities.

The laser (LASER), originating from the principle of stimulated emission proposed by Albert Einstein, has been a catalyst for substantial advancements across numerous industrial and scientific domains. Initially confined to research and laboratory applications, the scope of laser technology has expanded rapidly over time. This expansion is primarily due to the laser's unique characteristics, such as high-density energy output and precise beam control, which have facilitated its widespread integration into contemporary industrial practices. Specifically, laser materials processing technology enables the machining of diverse materials, including metals, ceramics, and polymers, in a non-contact manner, thereby achieving high precision without the risk of wear or contamination. As a result, laser processing has become indispensable in fields such as advanced electronics manufacturing, medical device production, aerospace, and the automotive industry. Furthermore, laser materials processing exhibits significant potential for high-precision applications that demand minimal thermal deformation of materials, such as microfabrication and the production of complex geometries. This paper provides a comprehensive examination of the development and necessity of laser processing technology, explores various laser types and their possible applications, and elucidates why laser technology has emerged as a fundamental component of modern manufacturing, alongside its trajectory for future development.

New material design has obtained tremendous attention in material science community as the performance of new materials, especially in nano length scale, could be greatly improved to applied in modern industry. In certain conditions limiting experimental synthesis of these new materials, new approach by computer simulation has been proposed to be applied, being able to save time and cost. Recent development of computer systems with high speed, large memory, and parallel algorithms enables to analyze individual atoms using first principle calculation to predict quantum phenomena. Beyond the quantum level calculations, mesoscopic scale and continuum limit can be addressed either individually or together as a multi-scale approach. In this article, we introduced current endeavors on material design using analytical theory and computer simulations in multi-length scales and on multi-physical properties. Some of the physical phenomena was shown to be interconnected via a cross-link rule called ``cross-property relation``. It is suggested that the computer simulation approach by multi-physics analysis can be efficiently applied to design new materials for multi-functional characteristics.