Thermal metamaterials, designed by transformation thermodynamics are artificial structures that can actively control heat flux at a continuum scale. However, fabrication of them is very challenging because it requires a continuous change of thermal properties in materials, for one specific function. Herein, we introduce tunable thermal metamaterials that use the assembly of unit-cell thermal shifters for a remarkable enhancement in multifunctionality as well as manufacturability. Similar to the digitization of a two-dimensional image, designed thermal metamaterials by transformation thermodynamics are disassembled as unit-cells thermal shifters in tiny areas, representing discretized heat flux lines in local spots. The programmed-reassembly of thermal shifters inspired by LEGO enable the four significant functions of thermal metamaterials-shield, concentrator, diffuser, and rotator-in both simulation and experimental verification using finite element method and fabricated structures made from copper and PDMS. This work paves the way for overcoming the structural and functional limitations of thermal metamaterials.Active control of thermal energy through mediums is a significant subject with applicability in diverse fields, from fundamental physics to practical applications. Understanding thermal energy transport at nano-microscales mainly depends on the phonon distribution and contact interface of layers 1 . Manipulation of thermal energy transport at macroscales has been regarded as equivalent to the control of heat flux through the material, because of its diffusive nature through specific mediums at continuum scales 1,2 . Most research about macroscale thermal transport has focused on the development of bulk materials or mediums that promote thermal transport with superior thermal conductivity or suppress heat transfer with thermal insulation and grain boundaries 3,4 . The progress of micro-nanotechnologies has enabled advanced research into a new class of materials with desirable properties, by means of using embedded fillers in composite structures [5][6][7] . However, such methods have reached the limit for achieving breakthroughs in terms of active control of thermal energy near local spots in macroscales, since they inevitably depend on thermal properties of mediums.The development of metamaterials that are able to manipulate diverse physical properties using artificially designed structures have been introduced as a new approach to overcome previous limitations of transport phenomena through the mediums. Transformation optics was one of general approaches to design cloaking devices or optical waveguides [8][9][10][11][12][13][14] . This method was applicable to microwave frequencies as well 13 , and experimental verifications have been conducted in the visible wavelength region 15 . Furthermore, transformation thermodynamics has been recently extended to design new kinds of thermal metamaterials 16 , which actively control heat flux through diverse mediums in millimeter to centimeter scales, dominated b...

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The development of advanced technologies for wireless data collection and the analysis of quantitative data, with application to a human-machine interface (HMI), is of growing interest. In particular, various wearable devices related to HMIs are being developed. These devices require a customization process that considers the physical characteristics of each individual, such as mounting positions of electrodes, muscle masses, and so forth. Here, the authors report device and calculation concepts for flexible platforms that can measure electrical signals changed through electromyography (EMG). This soft, flexible, and lightweight EMG sensor can be attached to curved surfaces such as the forearm, biceps, back, legs, etc., and optimized biosignals can be obtained continuously through post-processing. In addition to the measurement of EMG signals, the application of the HMI has stable performance and high accuracy of more than 95%, as confirmed by 50 trials per case. The result of this study shows the possibility of application to various fields such as entertainment, the military, robotics, and healthcare in the future.

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Near-field communication (NFC) is a low-power wireless communication technology used in contemporary daily life. This technology contributes not only to user identification and payment methods, but also to various biomedical fields such as healthcare and disease monitoring. This paper focuses on biomedical applications among the diverse applications of NFC. It addresses the benefits of combining traditional and new sensors (temperature, pressure, electrophysiology, blood flow, sweat, etc.) with NFC technology. Specifically, this report describes how NFC technology, which is simply applied in everyday life, can be combined with sensors to present vision and opportunities to modern people.