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The cardiac contractility in human heart was investigated by analyzing deformation of the left ventricular wall during systole using a magnetic resonance tagging technique. Subjects were ten normal humans, eight patients with a hypertrophic cardiomyopathy (HCM), and seven patients with a hypertensive heart disease (HHD). The circumferential strain at a short-axis section was employed as an index for an evaluation of the cardiac contractility. The obtained results showed that the circumferential strains in local regions of the patients with a HCM were significantly smaller compared with those in corresponding regions of the normal humans, while the circumferential strains of the patients with a HHD were similar to those of the normal humans in whole regions. This study may suggest that the circumferential strain could be an effective index for the quantitative evaluation of the cardiac contractility.

A numerical simulation system using the three-dimensional finite element method (3D-FEM) is established to reproduce the performance of the left ventricle during one cardiac cycle, which may ultimately provide useful information for medical diagnoses. The simulation system consists of a 3D-FEM mechanical model of the left ventricle based on four fundamental models, that is, (1)a mechanical model of myocardial muscle fiber which produces the active force, (2)a mechanical model of the left ventricle which is composed of the myocardial muscle fiber, (3)a transmission model of electric stimulus, and (4)a circulatory system model which gives the pre- and after-loads to the left ventricular model. In this paper, the fundamental system of the simulator is explained, and some typical examples of computational results obtained by this system are shown and discussed. The reliability of the simulator is examined by comparing some numerical results with the corresponding results obtained by medical imaging technique.

Superelasticity is very applicable property of Shape Memory Alloys (SMA) with good perspective for its implementation in engineering practice. For application of any material in practice it is important to obtain an appropriate knowledge on the material i.e. to know all the material characteristics which are relevant for the safe and reliable performance during the life cycle. Very often new materials can not be characterised completely by using the already known and established method, and for the characterisation of the special properties of new materials some new experimental techniques, methods or procedures are necessary. In the paper are presented some results from the study on superelastic behavior of SMA under tension and pure bending loading. Results were initiation for the generally presented study which is in progress, and is focused on new method on characterisation of compression characteristics of SMA.

The thermoelastic martensitic transformation/MT/ induced by combination of external forces at constant temperature has been investigated by tension-torsion experiments with hollow bar specimens of Cu-Al-Zn-Mn polycrystalline shape memory alloy /SMA/. The mechanical work stored or released by independent external axial and torque forces has been related with the progress of MT. The reversibility of large inelastic strains and mechanical hysteresis of pseudoelastic material give rise to peculiar mechanical behaviors under general stress conditions, that are experimentaly described here. It is shown, that at least at low stresses, the polycrystalline SMA material can be loaded - unloaded by combination of general forces with precisely defined and well reproducible strain response for hundreds of cycles, provided that axial strains are reversible. The reversible axial strains can be controlled by change of torque force and vice versa due to the coupling among tension and torsion typical for deformation mechanism of thermoelastic MT. There is a tendency of reverse martensitic transformation on unloading to follow the already passed forward transformation pathway, but the effect is rather weak in SMA polycrystal.

The modern science and technology born and developed rapidly after the 19th century in Europe, have undoubtedly given us the benefit to free from the severe condition of nature, some slavery works, hunger, and pain. So that, we have been able to enjoy our converient, comfortable and creative lives. However, it is the fact disappointingly that the dogmatism of science and technology with only local onterests and urgent pursuit of economic efficiency have brought the huge consumption and wastes of energies and resources, the serious environmental pollution, and also the depressions of economical and industrial activities. In thus standpoints, we discuss and propose some desirable researches and educations in science and technology for the coming postmodern age. This paper is consisted following contents ; Development of modern science and fundamentals of advanced technology (Science and engineering Marionics), Engineering education as human resources development (in Japanese university, for refreshing the engineers in industrial company), and as the main and conclusive discussion. Beyond the science and the proper aims of the engineering (From Shokusan industrial engineering to Shadatsu human engineering).

Inhomogeneous stress and strain distributions in the crystal grain component embedded in the polycrystal structure and their development were estimated numerically by using a 2-D finite element model of polycrystal based on the crystal plasticity. The micro-macro transition in the palstic deformation of polycrystalline metal is discussed by using the numerical results. Moreover, the realistic value of an accommodation parameter which is a key parameter relating micro- and macro-variables is discussed for the cases of several deformation pathes.

The finite element method (FEM) is a very powerful device for solving many continuum mechanics problems which can be treated neither theoretically nor experimentally. In this paper FEM is developed for an analysis of semimicroscopic effects within inelastically deformed polycrystalline metals and their collective action to its macroscopic response.

In order to make the TiNi shape memory alloy (SMA) with arbitrary shape couture, the lost wax fine casting and self-propagating high-temperature synthesis (SHS) method can be applied. However, the SMA produced by these methods donot carries out some process. Thus the shot peening process is applied to improve the mechanical properties of SMA instead of cold roll process. In this study, we investigated the effect of the shot peening process for the improvement of the properties of SMA., 日本機械学会M&M2006材料力学カンファレンス 2006年8月4～6日 浜松市 発表梗概, 燃焼合成法を応用した新精密鋳造TiNi形状記憶合金の特性解明・応用

The two-way shape memory effect is expected as unique mechanical property for new engineering applications of shape memory alloys such as micro actuators. The two-way shape memory effect occurs by giving internal stress field to shape memory alloys. The mechanical loading training is the method to give internal stress field. The mechanism of the two-way shape memory behavior have not been understood yet. In this study, the two-way shape memory behavior obtained by the mechanical loading training was investigated experimentally. The obtained results are presented and discussed in this paper., 日本機械学会M&M2006材料力学カンファレンス 2006年8月4～6日 浜松市 発表梗概, 燃焼合成法を応用した新精密鋳造TiNi形状記憶合金の特性解明・応用

The shape memory alloys have been expected from a view point of engineering applications because of its unique mechanical properties. When the shape memory alloy which was deformed at low temperature is heated in the condition with the restriction of strain, the recovery stress occurs by a reverse transformation. In this study, the recovery stress after the torsional loading condition was experimentally investigated in TiNi shape memory alloy tube manufactured by the sintering synthetic method. The obtained results are discussed in this paper., 日本機械学会M&M2006材料力学カンファレンス 2006年8月4～6日 浜松市 発表梗概, 燃焼合成法を応用した新精密鋳造TiNi形状記憶合金の特性解明・応用

By using lost wax fine casting and self-propagating high-temperature synthesis (SHS), we made the new TiNi shape memory alloy (SMA) that is homogeneous and arbitrary shape. The purpose of this research is to clarify the mechanical properties of TiNi shape memory alloy made by lost wax fine casting and to help practical application of this new material. In this study, we performed the tensile tests under various temperatures to this material and observed the deformation behavior. In this paper, the obtained results are shown and discussed., 日本機械学会2005年度年次大会 2005年9月19～22日 調布市 発表梗概, 燃焼合成法を応用した新精密鋳造TiNi形状記憶合金の特性解明・応用

The shape memory properties of a casting TiNi shape memory alloy (SMA) were studied. Base materials were prepared as a self-propagating high-temperature synthesis (SHS) ingot. The composition of these ingots was Ti-50.4at%Ni.The ingot was cast into a shape of specimen by lost wax fine casting. The heat-treatment conditions were 480℃-40min. Shape memory characteristics were measured by differential scanning calorimetry (DSC) and X-ray diffraction (XRD)., 日本機械学会2005年度年次大会 2005年9月19～22日 調布市 発表梗概, 燃焼合成法を応用した新精密鋳造TiNi形状記憶合金の特性解明・応用