다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Humans are undergoing a fateful transformation focusing on artificial intelligence, quantum information technology, virtual reality, etc., which is inseparable from intelligent nano-micro devices. However, the booming of "Big Data" brings about an even greater challenge by growing electromagnetic radiation. Herein, an innovative flexible multifunctional microsensor is proposed, opening up a new horizon for intelligent devices. It integrates "non-crosstalk" multiple perception and green electromagnetic interference shielding only in one pixel, with satisfactory sensitivity and fast information feedback. Importantly, beneficial by deep insight into the variable-temperature electromagnetic response, the microsensor tactfully transforms the urgent threat of electromagnetic radiation into "wealth," further integrating self-power. This result will refresh researchers' realization of next-generation devices, ushering in a new direction for aerospace engineering, remote sensing, communications, medical treatment, biomimetic robot, prosthetics, etc.

Variable-Temperature Electron Transport and Dipole Polarization Turning Flexible Multifunctional Microsensor beyond Electrical and Optical Energy.

This paper will review the evolution of wearable textile antennas over the last couple of decades. Particular emphasis will be given to the process of embroidery. This technique is advantageous for the following reasons: (i) bespoke or mass produced designs can be manufactured using digitized embroidery machines; (ii) glue is not required and (iii) the designs are aesthetic and are integrated into clothing rather than being attached to it. The embroidery technique will be compared to alternative manufacturing processes. The challenges facing the industrial and public acceptance of this technology will be assessed. Hence, the key opportunities will be highlighted.

https://www.mdpi.com/2079-9292/3/2/314/pdf?view=inline

Embroidery and related manufacturing techniques for wearable antennas: Challenges and opportunities

Wearable antennas have gained much attention in recent years due to their attractive features and possibilities in enabling lightweight, flexible, low cost, and portable wireless communication and sensing. Such antennas need to be conformal when used on different parts of the human body, thus need to be implemented using flexible materials and designed in a low profile structure. Ultimately, these antennas need to be capable of operating with minimum degradation in proximity to the human body. Such requirements render the design of wearable antennas challenging, especially when considering aspects such as their size compactness, effects of structural deformation and coupling to the body, and fabrication complexity and accuracy. Despite slight variations in severity according to applications, most of these issues exist in the context of body-worn implementation. This review aims to present different challenges and issues in designing wearable antennas, their material selection, and fabrication techniques. More importantly, recent innovative methods in back radiations reduction techniques, circular polarization (CP) generation methods, dual polarization techniques, and providing additional robustness against environmental effects are first presented. This is followed by a discussion of innovative features and their respective methods in alleviating these issues recently proposed by the scientific community researching in this field.

/pdf/wearable-antennas-a-review-of-materials-structures-and-5bzxx4cp70.pdf

Wearable Antennas: A Review of Materials, Structures, and Innovative Features for Autonomous Communication and Sensing

Potassium-ion batteries (KIBs) are a core energy storage device that can meet the need for scalable and affordable stationary applications because they use low-cost and earth-abundant potassium. In addition, KIB shares a similar storage mechanism with current Li-ion batteries. As the key to optimizing a battery's performance, the development of high-performance electrode materials helps to increase the feasibility of KIB technology. In this sense, phosphorus-based materials (i.e., phosphorus and metal phosphide) with high theoretical capacity and low redox potential tick all the right boxes as a material of choice. A rapid glimpse at recent studies on phosphorus-based anode materials for advanced KIBs is provided, covering the synthetic methods, reaction mechanisms, electrochemical properties, and performances. In addition, several promising strategies are highlighted to address the imminent challenges faced by phosphorus-based anode materials, hoping to cast an insightful outlook for possible future direction in this field.

The Promise and Challenge of Phosphorus-Based Composites as Anode Materials for Potassium-Ion Batteries.

The authors introduce two flat graded-index (GRIN) lens designs in this study. First of these is a thick lens, which was designed and fabricated by using the three-dimensional (3D)-printing technique. Second, a thin dial-a-dielectric (DaD) lens, which uses state-of-the-art artificially engineered dielectric materials for design and for which they present only the simulated results, with plans to fabricate it in the future. Both designs overcome the difficulties faced in finding desired commercial off-the-shelf materials, either for 3D-printing or for fabricating conventional GRIN lenses. The lenses comprise of several concentric dielectric rings with bespoke relative permittivities for transforming spherical waves into plane waves and vice versa. The 3D-printed thick flat lens is low-cost and light-weight, but provides broadband and high gain performance. Measurement results show that the realised gain of the thick lens is 9–11 dB over the frequency band of 12–18 GHz. The designed DaD lens has the desirable characteristics of low loss, low reflection and broadband properties.

3D-printed planar graded index lenses

A cold sintering process (150 °C, 30 min and 200 MPa) was employed to fabricate Na0.5Bi0.5MoO4–Li2MoO4 (NBMO-LMO) composites with up to 96.4% relative density. X-ray diffraction traces, backscattered electron images and Raman spectra indicated the coexistence of NBMO and LMO phases in all composites with no detectable secondary phases. The pemittivity (er) and temperature coefficient of resonant frequency (TCF) decreased, whereas microwave quality factor (Q × f) increased, with increasing weight % LMO. Near-zero TCF was obtained for NBMO-20 wt %LMO with er ∼ 17.4 and Q × f ∼ 7470 GHz. Functionally graded ceramics were also fabricated with 5 ≤ er ≤ 24. To illustrate the potential of these cold sintered composites to create new substrates and device architecture, a dielectric graded radial index lens was designed and simulated based on the range of er facilitated by the NBMO-LMO system, which suggested a 78% aperture efficiency at 34 GHz.

Cold-sintered temperature stable Na0.5Bi0.5MoO4−Li2MoO4 microwave composite ceramics

Simulated and measured microstrip patch antennas produced using embroidery techniques have been presented. The antennas use a standard microwave substrate material. The effect of stitch direction and stitch density is described and a clear requirement to understand how the currents flow in an antenna, so that the stitch direction can be correctly chosen is shown. Two different simulation approaches for these antennas are discussed and one is linked to measurement results, pointing to a simplified model for simulating embroidered patch antennas.

/pdf/effect-of-the-fabrication-parameters-on-the-performance-of-2w8t7mlyzp.pdf

Effect of the fabrication parameters on the performance of embroidered antennas

This letter presents dielectric properties of air filled synthetic substrates fabricated in a single process using three-dimensional printing. The permittivity and loss tangent of a given sized substrate can be changed by controlling the air infill volume fraction. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2344–2346, 2015

Shiyu Zhang

Papers

3D-printed planar graded index lenses

Cold-sintered temperature stable Na0.5Bi0.5MoO4−Li2MoO4 microwave composite ceramics

Effect of the fabrication parameters on the performance of embroidered antennas

Novel 3D printed synthetic dielectric substrates

Cold sintered CaTiO3-K2MoO4 microwave dielectric ceramics for integrated microstrip patch antennas