Shape memory alloys (SMAs) are a fascinating group of metals that have two remarkable properties, the shape memory effect and superelasticity.1,2 Shape memory refers to the recovery of shape (i.e., strain) after apparent ''permanent'' deformation (induced at relatively cold temperatures) by heating above a characteristic transformation temperature (often near room temperature [RT]). Superelasticity refers to the isothermal recovery of relatively large strains during a mechanical load-unload cycle that occurs at temperatures above a characteristic transformation temperature. A large number of SMAs have been discovered since the mid-1900s to late 1900s, and the list continues to grow.3 Many of these alloys, while scientifically interesting, consist of precious metals or only exhibit useful properties as single crystals, which do not lend them to practical use in commercial applications. A few alloys, however, have emerged as commercially viable for novel devices. These include certain copper alloys (CuAlZn) and nickel-titaniumbased alloys, such as near-equiatomic NiTi, known as Nitinol (first discovered in the early 1960s) and some ternary alloys such as NiTiCu and NiTiNb (see Fig. 1). To date, it is fair to say that NiTi-based SMAs have the best memory and superelasticity properties of all the known polycrystalline SMAs. The NiTi family of alloys can withstand large stresses and can recover strains near 8% for low cycle use or up to about 2.5% strain for high cycle use. This strain recovery capability can enable the design of novel devices in either a thermally active mode or an isothermal energy absorption mode. NiTi SMAs have other advantages in terms of corrosion resistance, fatigue resistance, and biocompatibility, thereby making them the preferred material system for most shape memory applications being considered today.The materials science and mechanics literature regarding SMAs are vast, and we will not attempt a complete review here (see Otsuka and Ren 4 for a recent review). The field remains an active area of research, and the understanding of the mechanisms involved at all scales from the crystalline lattice to the macroscopic scale has progressed significantly, even during the past decade or so. Furthermore, advances in materials processing have resulted in production of Nitinol SMAs with good quality control, with reproducible properties, and in relatively large quantities. Nitinol wire, in particular, is being produced with excellent properties and is relatively inexpensive compared to most other forms. Applications of SMA wire are now being seriously considered even in costsensitive engineering sectors.5 Consequently, our focus in this article is on the thermomechanical behavior of polycrystalline Nitinol wire under uniaxial tensile loading.Shape memory alloys exhibit some rather surprising phenomena as well as extreme sensitivities to testing conditions, which can create pitfalls in material testing and interpretation for someone who is new to SMAs. As we like to say-it is not an amateur sport. N...

Purpose The purpose of this paper is to examine how the emergent 3D interactive media technologies are used as a viable tool for enhancing visitors’ overall experiences at an exhibition entitled, 300 Years of Hakka Kungfu – Digital Vision of Its Legacy and Future (Hakka Kungfu Exhibition) – presented and co-organized by the Intangible Cultural Heritage Office of Hong Kong, International Guoshu Association and the School of Creative Media, City University of Hong Kong. Design/methodology/approach A questionnaire survey in both online and paper-based formats was used for identifying visitors’ experiences in the interactions with the multimedia technologies. For this research study, a questionnaire, consisting of 26 items, was set out to measure the visitors’ experiences at the Exhibition. Since the Exhibition was about presenting a centuries-old Chinese cultural heritage, Hakka Kungfu via the use multimedia technologies, in the context of establishing a dialogue between the past and present, the researchers included questionnaire items that were devoted to enquire about the level of understanding, knowledge and enjoyment, and visitors’ new knowledge about Hong Kong history and culture was successfully disseminated to the respondents at the end of the questionnaire. Findings A total of 209 completed questionnaires were collected at this Hakka Kungfu Exhibition. The findings reveal that the exhibits did attract people at all ages. This Exhibition gave the visitors a sense of interest and wonder in the object and information presented in the Exhibition. Findings of this study also reveal that this Exhibition has successfully attracted a large number of female visitors, as well as visitors who have never taken any martial arts training. In addition, visitors’ Exhibition experience was found to be memorable, as well as enjoyable. Furthermore, visitors’ experience within the Exhibition suggested that it was entertaining, as well as educational. By creating a long-lasting impact on the minds of these Exhibition visitors about the connections between and relevance of traditional Chinese Kungfu, their collective cultural identity, as well as the contemporary society we live in. The Exhibition exemplified the successful integration of the presentation of Kungfu as a form of cultural heritage with engagement-creating technology, in which technology is unobtrusive but effective. Originality/value Although it is already a global trend for the museums to integrate multimedia technologies into their exhibitions, research on the situation and feedback of multimedia technology used in the museum exhibitions in Hong Kong is scarce as well as scattered. Findings of this study could help identify various factors involved in audience participation, thereby exploring the possibility of building a contact point/space for traditional Chinese Kungfu as an intangible cultural heritage, via the integration of the latest media technologies. In particular, the development of multimedia technologies has become increasingly important to museums, and museum professionals have been exploring how digital and communication technologies can be developed to offer visitors a more interactive, personalized museum experience. In general, despite the growing interest in deploying digital technology as interpretation devices in museums and galleries, there are relatively few studies that examine how visitors, both alone and with others, use new technologies when exploring the museum contents.

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