Shape memory fundamentals

Beyond the usual mechanical and electrical performances, this review also points out the emergence of other original properties, like the remarkable capability of some nanotube/PVA composites to absorb mechanical energy and shape memory phenomena that differ from traditional behaviors of other polymers. These features are opening new investigation fields, in which several fundamental questions will have to be solved. But they also offer new opportunities for a variety of applications like smart or protective clothing, helmets, bullet proof vests, or active composites. 

From the crude fabrications of the earliest surgical instruments to the highly sophisticated devices of today, materials are the fundamental component of a medical device. Modern devices are usually composed of a metal, plastic, alloy, or various combinations thereof. Improvements in technology have created lighter, stronger materials as well as shape-memory alloys such as nitinol, resulting in major innovations in device design and functionality. 

R. Kainuma, H. Nakano, K. Oikawa, K. Ishida, T. Nishizawa High Temperature Shape Memory Alloys of Ni-Al Base Systems. In C.T. Liu, M. Wuttig, K. Otsuka et al. Shape-Memory Materials and Phenomena - Fundamental Aspects and Applications. MRS, Pittsburgh (1992) 403-408. 

Ding, Z, PumawaU, H., Tang, C., and Zhang, J.L. (2012) Thermo/chemo-responsive shape memory effect in polymers a sketch of working mechanisms, fundamentals and optimization. /. Polym. Res., 19 (9), 1—34. 

Although there has been much research regarding the effects of various inorganic nanofillers on the intrinsic properties of shape memory networks, there is still significant room at both the fundamental and the applied research levels for investigating novel methods that explore and elucidate the structure-property relationships, synthesis, and mass fabrication of SMPlNCs. After observing the current applications for these composites in the oil and gas industry [132], as intelligent fabrics [133], and many more [134, 135], there is an obvious untapped potential for SMPlNCs. 

Miyazaki, S., Fu, Y.Q. and Huang, W.M. (2009) Thin Film Shape Memory Alloys Fundamentals and Device Applications. New York Cambridge University Press. 

However, the power of any particular screen reader is in the degree to which the other capabilities dictated by the use of the GUI are achieved. The fundamental differences in the ways that a text-only command-line interface (CLI) and a GUI provide output to the video screen present access problems for persons who are blind. These are related to both the ways in which internal control of the computer display is accomplished and the ways in which the GUI is employed by the computer user (Boyd et al., 1990). The CLI-type interfaces use a memory buffer to store text characters for display. Since all the displayed text can be represented by ASCII code, it is relatively easy to use a software program and to divert text from the screen to a speech synthesizer or Braille display. However, this type of screen reader is unable to provide access to charts, tables, or plots because of their graphic features. This type of system is also limited in the features that can be used with text. For example, features such as size, shape, and font or alternative graphic forms are not captured in standard ASCII text code. 

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