A novel high voltage operation featured wireless power transfer system for monitoring equipment charging on 110 kV high voltage transmission line based on magnetic resonant coupling is studied and designed. With consideration of operation environment on transmission line and electrical transmission tower, an overall scheme is proposed through installation position, coupling structure and driving topology design. In order to improve system's suitability in high voltage environment, related optimization methods, including constraining power flow path, improving quality factor and coupling have been adopted. Since the coupling coils are fixed at both ends of insulator string, barrel shaped high permeability material layer is added to constrain the magnetic field distribution. Moreover, cross-impacts between transmission line and the charging system are analyzed. The influence of power frequency magnetic field on charging system is calculated and electric distribution of insulator string with the charging system are simulated. Analysis results indicate that cross-impacts can be negligible. Experimental results verify that the transmission power can meet power supply requirements and the designed charging system can be operated stably under high voltage condition.

Compression textiles as adjuvant physical interventions are increasingly applied for prophylaxis and treatment of chronic venous insufficiency (CVI), providing benefits of calibrated compression and controlled stretch. Pressure dosage delivered and mechanical properties (stiffness, elasticity and hysteresis) are determined by material nature, stitches structures, fabrication technology and delivery modes. Laplace’s Law and Pascal’s Law contribute to elaborate the static and dynamic working mechanisms behind the interaction between compression interventions and a biological body. However, there is still a lack of sufficient awareness on compression materials, and there is controversy regarding the best solution for clinical application of compression. This study integrates the views from physiology, pathophysiology, biomechanics, material science and textile engineering, to review and clarify physical–mechanical characteristics of compression materials, working mechanisms of textile-based compression interventions and their medical benefits in chronic venous insufficiency treatment. The aim is to enhance understanding of compression textiles applied in compression therapy, and to facilitate cooperation among multiple parties working in related supply chains, thus promoting textile-based compression interventions in chronic venous insufficiency treatment and growth of technical textiles applied in healthcare, medical and rehabilitation fields.

Background The beneficial effects of graduated elastic compression stockings (GCSs) have been demonstrated. However, their pressure performances are variable and unstable in practical applications owing to many influencing factors. Comprehensive assessment of skin pressure profiles may help elucidate the mechanisms of action of compression stockings. Objective The objective of this study was to quantify and objectively evaluate the magnitude and distribution of skin pressure applied by different GCSs and to analyze the possible reasons influencing the stocking pressure performances. Methods Six healthy females were required to wear eight kinds of GCSs with different pressure levels while standing upright. The skin pressures of 16 different positions located in four heights and four directions of the lower limb were measured and recorded by FlexiForce interface pressure sensors (Tekscan, Inc., Boston, MA, USA) and a multichannel measuring system. Results The pressure gradients, pressure levels, and testing locations significantly influenced skin pressure (p < .001). All tested GCSs exerted the highest pressure at the ankle region, and the pressure gradually decreased toward the thigh, which follows the gradient design of GCSs. However, many of them failed to produce the perfect pressure gradients from the ankle region to the calf region. Obviously, reversed pressure gradients occurred in the medial side of the leg, where the pressure at the ankle region was lower than that on the prominent part of the calf by 36% on average. GCSs with higher pressure levels applied higher skin pressure on the lower limb. The pressure at the anterior side was far higher than that in the medial and lateral directions. The distribution patterns of skin pressure at transverse sections were similar to the anatomic outlines of cross sections of the leg. The measured average ankle pressure of all tested GCSs did not reach the pressures specified by the manufacturers. Conclusion Skin pressure distributions and magnitudes applied by GCSs were significantly influenced by the locations of testing points in terms of height and direction, which are determined by the specific anatomic structure and body shape of individual human legs and potentially influenced by the pressure sensor and testing methods.

This study reviews the state of the art in structural design and the corresponding mechanical behaviours of composite vascular grafts. We critically analyse surface and matrix designs composed of layered, embedded, and hybrid structures along the radial and longitudinal directions; materials and manufacturing techniques, such as tissue engineering and the use of textiles or their combinations; and the corresponding mechanical behaviours of composite vascular grafts in terms of their physical–mechanical properties, especially their stress–strain relationships and elastic recovery. The role of computational studies is discussed with respect to optimizing the geometrics designs and the corresponding mechanical behaviours to satisfy specialized applications, such as those for the aorta and its subparts. Natural and synthetic endothelial materials yield improvements in the mechanical and biological compliance of composite graft surfaces with host arteries. Moreover, the diameter, wall thickness, stiffness, compliance, tensile strength, elasticity, and burst strength of the graft matrix are determined depending on the application and the patient. For composite vascular grafts, hybrid architectures are recommended featuring multiple layers, dimensions, and materials to achieve the desired optimal flexibility and function for complying with user-specific requirements. Rapidly emerging artificial intelligence and big data techniques for diagnostics and the three-dimensional (3D) manufacturing of vascular grafts will likely yield highly compliant, subject-specific, long-lasting, and economical vascular grafts in the near-future.Graphic abstract