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Results of permittivity measurements, electromagnetic interference shielding effectiveness, and heat generation due to microwave absorption in conducting polymer coated textiles are reported and discussed. Intrinsically conducting polymer, polypyrrole doped with anthraquinone-2-sulfonic acid (AQSA) or para-toluene-2-sulfonic acid (pTSA) was applied on textile substrates and the resulting materials were investigated in the frequency range 1-18 GHz. Conducting textile/polypyrrole composites interacted with incident microwaves and generated absorption levels of up to 48 % in a 0.54 mm thick substrate. A thermography station was used to monitor these composites during simultaneous subjection to microwave radiation, where absorption was confirmed via visible heat losses. Lower conductivity samples showed larger amounts of heat loss due to microwave absorption compared to samples with higher conductivity. A sample with an average sheet resistivity of 120 Ω/sq. showed a maximum temperature of 27.15ºC whilst a sample with a lower resistivity (105 Ω/sq.) reached 26.65ºC (Ambient temperature: 22.8ºC).

Realistic modeling of soft tissue deformation has been recognized as an essential requirement for virtual surgical simulators. As a consequence, the constitutive model is crucial for modeling soft tissue deformation. In this paper, the significance and characteristics of soft tissue deformation in virtual surgery simulation studies are introduced and analyzed its challenges. We have been focusing on investigating the constitutive relations in the soft tissue mechanical models: viscoelastic models and hyper-elastic models. Moreover, some techniques are given to determine and optimize model parameters through biomechanical experiments. Finally, based on the existing constitutive model, a novel notion for optimizing the soft tissue deformation constitutive model is proposed. The contribution of this paper is to provide theoretical guidance for the simulation of soft tissue deformation in the virtual surgery simulation system and to supply various practical suggestions for developing new constitutive models in the future.

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Vection is classically defined as the illusory perception of self-motion induced via visual stimuli. The utility of vection research lies in its potential to enhance simulation fidelity as measured through presence and reduce the probability that motion sickness symptoms occur through the identification of differences and similarities in physiological responses to vection and motion sickness. Recent studies have shown a multimodal interaction of various sensory systems in facilitating vection. Moreover, the utility of co-stimulating some of these sensory systems along with the presentation of visual stimuli have been reviewed. However, a review on the tactile mediation of vection appears to be missing from literature. The purpose of this review is to evaluate the current methodologies, and utility of, tactile stimulation in vection research. We searched for articles through EBSCOHost, Scopus and Web of Science. Only studies were included wherein an experiment on the effect of tactile stimulation on human self-motion perception was detailed. Twenty-three studies were obtained and distilled in tabular form. The studies reviewed presented a strong variability in the a-priori definition of vection, methodological inhomogeneity, varying approaches to the assessment of subjective vection measures and a lack of objective measures. We discuss the need for more qualitative research to reduce methodological inhomogenities, recommend future research in tactile-mediated vection to investigate stimulation to the torso, and suggest further investigation into the utility of concurrently presenting different forms of tactile stimulation.