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51.
《Ergonomics》2012,55(11):1551-1557
Abstract This paper examines (1) the responses of participants in specific indoor sports to questions regarding their self-perceived health and fitness, and (2) the relation betweeen these responses and body composition. A representative sample of indoor sports participants (n = 4308; 2938 male and 1370 female) from six cities in the United Kingdom responded to a questionnaire concerned with their self-perception of health and fitness. Height and weight was established from self-report and a body mass index (BMI) was calculated. Seventy eight percent of males and 85% of females reported their health as ‘good’ or ‘excellent’. Less than 2% of the sample reported their health as ‘poor’ or ‘very poor’. However, only 67% of males and 67% of females reported their fitness as ‘good’ or ‘excellent’. Again, the proportion of the sample reporting ‘poor’ or ‘very poor’ fitness was low; less than 4%. The question on health was compared with a recent general population survey and this yielded markedly more ‘unfavourable’ results; only 72% of males and 70% of females reported their health as being ‘good’ or ‘excellent’. A comparison of the response category groups for BMI showed significant differences between the ‘poor’ and ‘fair’ groups but not between the ‘good’ and ‘excellent’ groups. It is concluded that: (1) indoor sports participants regard their health and fitness highly, but their fitness less so than their health; (2) adiposity tends to be associated with poorer perceptions of health and fitness; (3) women sports participants perceive their health more highly than others of the same age compared with men, yet the reverse is true of fitness. 相似文献
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通过近年来对新型防水材料的工程设计和应用实践,以全新的角度对刚性和柔性防水体系的特点进行了分析和研究,提出了以刚性为主,柔性为辅的新防水结构体系设计理念,同时指出了传统防水设计方面存在的一些误区和缺陷。 相似文献
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某钢结构人行天桥的静载试验结果与理论分析结果偏差较大,为查找原因,首先深入分析试验结果的特征,推断出其主要原因,然后通过进一步的有限元理论分析证明了这种推断的准确性,最后还讨论了这种偏差导致结构受力的变化。 相似文献
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Arif M. Abdullah Xiuling Li Paul V. Braun John A. Rogers K. Jimmy Hsia 《Advanced functional materials》2020,30(14)
Self‐assembly of 3D structures presents an attractive and scalable route to realize reconfigurable and functionally capable mesoscale devices without human intervention. A common approach for achieving this is to utilize stimuli‐responsive folding of hinged structures, which requires the integration of different materials and/or geometric arrangements along the hinges. It is demonstrated that the inclusion of Kirigami cuts in planar, hingeless bilayer thin sheets can be used to produce complex 3D shapes in an on‐demand manner. Nonlinear finite element models are developed to elucidate the mechanics of shape morphing in bilayer thin sheets and verify the predictions through swelling experiments of planar, millimeter‐scaled PDMS (polydimethylsiloxane) bilayers in organic solvents. Building upon the mechanistic understandings, The transformation of Kirigami‐cut simple bilayers into 3D shapes such as letters from the Roman alphabet (to make “ADVANCED FUNCTIONAL MATERIALS”) and open/closed polyhedral architectures is experimentally demonstrated. A possible application of the bilayers as tether‐less optical metamaterials with dynamically tunable light transmission and reflection behaviors is also shown. As the proposed mechanistic design principles could be applied to a variety of materials, this research broadly contributes toward the development of smart, tetherless, and reconfigurable multifunctional systems. 相似文献
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Yasin Cotur Michael Kasimatis Matti Kaisti Selin Olenik Charis Georgiou Firat Güder 《Advanced functional materials》2020,30(16)
A highly flexible, stretchable, and mechanically robust low‐cost soft composite consisting of silicone polymers and water (or hydrogels) is reported. When combined with conventional acoustic transducers, the materials reported enable high performance real‐time monitoring of heart and respiratory patterns over layers of clothing (or furry skin of animals) without the need for direct contact with the skin. The approach enables an entirely new method of fabrication that involves encapsulation of water and hydrogels with silicones and exploits the ability of sound waves to travel through the body. The system proposed outperforms commercial, metal‐based stethoscopes for the auscultation of the heart when worn over clothing and is less susceptible to motion artefacts. The system both with human and furry animal subjects (i.e., dogs), primarily focusing on monitoring the heart, is tested; however, initial results on monitoring breathing are also presented. This work is especially important because it is the first demonstration of a stretchable sensor that is suitable for use with furry animals and does not require shaving of the animal for data acquisition. 相似文献
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Tengfei Qiu Bin Luo Eser Metin Akinoglu Jung‐Ho Yun Ian R. Gentle Lianzhou Wang 《Advanced functional materials》2020,30(31)
Metallic mesh materials are promising candidates to replace traditional transparent conductive oxides such as indium tin oxide (ITO) that is restricted by the limited indium resource and its brittle nature. The challenge of metal based transparent conductive networks is to achieve high transmittance, low sheet resistance, and small perforation size simultaneously, all of which significantly relate to device performances in optoelectronics. In this work, trilayer dielectric/metal/dielectric (D/M/D) nanomesh electrodes are reported with precisely controlled perforation size, wire width, and uniform hole distribution employing the nanosphere lithography technique. TiO2/Au/TiO2 nanomesh films with small hole diameter (≤700 nm) and low thickness (≤50 nm) are shown to yield high transmittance (>90%), low sheet resistance (≤70 Ω sq?1), as well as outstanding flexural endurance and feasibility for large area patterning. Further, by tuning the surface wettability, these films are applied as easily recyclable flexible electrodes for electrochromic devices. The simple and cost‐effective fabrication of diverse D/M/D nanomesh transparent conductive films with tunable optoelectronic properties paves a way for the design and realization of specialized transparent electrodes in optoelectronics. 相似文献