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A contactless electromyography (EMG) electrodes design and development for prosthetics, particularly the Touch Hand 3, was the main objective of this paper. The correlation between EMG electrodes and patch antenna are described, with the problem relating to the dimensions of the covidien electrodes. The purpose of this paper is to improve the signal strength of the EMG electrodes and having them to not be in contact with the skin to cause irritation in the person.

A combination of the contact covidien electrodes and aluminium foil was used to develop electrodes that were in a similar configuration than a Yagi antenna. Different layers of patch elements were designed, developed and implemented.

Different layers of Yagi-patch electrodes are tested with different volunteers and compared with the average signal strengths obtained from the covidien electrodes. An improvement in signal strength with the Yagi-patch electrodes has been found.

The purpose of the work was to design, develop and test EMG electrodes that are cost-effective, reusable and able to improve the signal strengths that are recorded, for better functionality of prosthetic devices.

The integration of EMG and antennae theory to implement a Yagi-patch EMG electrode to improve on signal reception. The electrodes have the properties of being cheap, easy available, can eliminate direct contact and avoiding patches on the skin. Comparison of different layered electrodes with the contactless electrodes close to the skin. Comparison of the different electrodes on a silicone sleeve, which are commonly worn by amputees, placed between the skin and the prosthetic’s socket. Testing the Yagi-patch electrodes with an application with the prosthetic Touch Hand, to allow for the control of a system such as the Touch Hand.

The balance patch is an important but not well studied area to maintain game fairness and improve player entertainment. In this paper, we examine the effect of balance patch on player's character preference and further explore the moderating effect of psychological distance and character selection pattern.

In study 1, a web crawler was used to get server-side data of 40, 974 multi-player online battle arena (MOBA) players through official application programming interfaces (APIs). A paired-T test and a stepwise regression were performed to verify the hypothesis. In study 2, a 2-patch type (buff vs nerf) × 2 psychological distance (near vs distant) × 2 character selection pattern (stable vs variable) between-subjects design was adopted to confirm the empirical conclusions through questionnaire survey design and further explored the mediating effect of patch adjustment perception.

The analyzed results showed that the buff patch led to an increase in players' character preference, while the nerf patch led to a decrease in players' character preference. Moreover, the main effect was mediated by patch adjustment perception. Furthermore, psychological distance and character selection pattern both moderated the relationship between balance patch and character preference changes. The character preference of the near psychological distance increased more significantly elicited by buff patches and decreased more significantly in an adverse situation. Similarly, players with variable selection pattern of characters were more sensitive to the stimuli, and the character preference of the variable group changed more significantly than that of the stable group caused by balance patch release.

This paper studies the influence of a patch on the balance of character strength on player preference, which expands the research on game balance and fairness. The present results contribute to the theoretical research on consumer behavior of psychological distance and character selection pattern elicited by balance patches. Meanwhile, the results indicate that psychological distance theory can apply to the study of the relationship between players and virtual characters.

In this work, the authors aim to employ the so-called linked-interpolation concept already tested on beam and quadrilateral plate finite elements in the design of displacement-based higher-order triangular plate finite elements and test their performance.

Starting from the analogy between the Timoshenko beam theory and the Mindlin plate theory, a family of triangular linked-interpolation plate finite elements of arbitrary order are designed. The elements are tested on the standard set of examples.

The derived elements pass the standard patch tests and also the higher-order patch tests of an order directly related to the order of the element. The lowest-order member of the family of developed elements still suffers from shear locking for very coarse meshes, but the higher-order elements turn out to be successful when compared to the elements from literature for the problems with the same total number of the degrees of freedom.

The elements designed perform well for a number of standard benchmark tests, but the well-known Morley's skewed plate example turns out to be rather demanding, i.e. the proposed design principle cannot compete with the mixed-type approach for this test. Work is under way to improve the proposed displacement-based elements by adding a number of internal bubble functions in the displacement and rotation fields, specifically chosen to satisfy the basic patch test and enable a softer response in the bench-mark test examples.

A new family of displacement-based higher-order triangular Mindlin plate finite elements has been derived. The higher-order elements perform very well, whereas the lowest-order element requires improvement.

Poor bending response is a major shortcoming of lower-order elements due to excessive representation of shear stress/strain field. Advanced finite element (FE) formulations for classical elasticity enhance the bending response by either nullifying or filtering some of the symmetric shear stress/strain modes. Nevertheless, the stress/strain field in Cosserat elasticity is asymmetric; consequently any attempt to nullify or filter the anti-symmetric shear stress/strain modes may lead to failure in the constant couple-stress patch test where the anti-symmetric shear stress/strain field is linear. This paper aims at enhancing the bending response of lower-order elements for Cosserat elasticity problems.

A four-node quadrilateral and an eight-node hexahedron are formulated by hybrid-stress approach. The symmetric stress is assumed as those of Pian and Sumihara and Pian and Tong. The anti-symmetric stress components are first assumed to be completely linear in order to pass the constant couple-stress patch test. The linear modes are then constrained with respect to the prescribed body-couple via the equilibrium conditions.

Numerical tests show that the hybrid elements can strictly pass the constant couple-stress patch test and are markedly more accurate than the conventional elements as well as the incompatible elements for bending problems in Cosserat elasticity.

This paper proposes a hybrid FE formulation to improve the bending response of four-node quadrilateral and eight-node hexahedral elements for Cosserat elasticity problems without compromising the constant couple-stress patch test.

The purpose of this paper is to propose a novel quasi-nonlocal coupling of the bond-based peridynamic model with the classical continuum mechanics model to fully take advantage of their merits and be free of ghost forces.

This study reconstructs a total energy functional by introducing a coupling parameter that alters only the nonlocal interactions in the coupling region rather than the whole region and a modified elasticity tensor that affects the local interactions. Then, the consistency of force patch test is enforced in the coupling region to completely eliminate the ghost force in a general energy-based coupling scheme. For a one-dimensional problem, these coupling parameters are further determined through an energy patch test to preserve the energy equivalence or through an l¹-regularization. And, for a two- or three-dimensional problem, depending on the existence of a solution to the discretized force patch test, they are determined through an l¹-minimization or l¹-regularization.

One- and two-dimensional numerical examples under affine deformation have been conducted to verify the accuracy of the quasi-nonlocal coupling method, which exhibits no ghost force. Moreover, the coupling model can reproduce almost the same deformation behaviors of points near the crack for a cracked plate under tension as that from a pure peridynamic model, the former with a rather low computational cost and an easier application of boundary conditions.

This work is aiming at getting over long-standing ghost force issues in the energy-based coupling scheme. The numerical results from the cracked plate problem are exhibited promising extension to dynamic problems.

Engineers have developed robust and efficient incompressible finite element formulations using tools such as the Patch Test and the counting of constraints/variables, the first one aimed at the development of consistent elements and the second one aimed at the development of non‐locking and stable elements. The mentioned tools are rooted in the physics of the continuum mechanics problem. Mathematicians, on the other side, developed complex and powerful tools to examine the convergence of finite element formulations, such as the inf‐sup condition, these methods are based on the properties of the elliptical PDEs that constitute the mathematical model of the continuum mechanics problem. In this paper we intend to understand the inf‐sup condition from an engineering perspective, so as to be able to incorporate it into the package of tools used in the development of finite element formulations.

The purpose of this paper is to evaluate and discuss colour properties, stability and lightfastness after accelerated exposure in xenon‐arc light apparatus, of 3D ink jet prints produced by using 3D colour printing process.

3D colour prints were produced using ZCorporation 3D printing method. The samples were divided into groups according to the finishing process applied (untreated, finished with different infiltrants). Colorimetric properties were measured using spectrophotometer. Samples were placed into xenon‐arc based weathering apparatus (Xenotest), using the preset glass filtered sunlight, standard indoor conditions. Colour stability was evaluated as change in colour after repeating the spectrophotometer measurements and comparing spectral and specific colorimetric values of initial and exposed samples.

Based on methodology used, the analysis has shown the changes in colour appearance of differently finished 3D prints, which were mostly attributed to chroma and lightness variations. The colour stability of samples studied noticeably varied and is dependent on colour, percentage of ink coverage and finishing method. Issues of colour and stability of 3D ink jet prints could become important as 3D printing emerges into new application areas, in which the object properties will need to be maintained for a certain amount of time.

The research is comparative and is limited to the specific materials and procedures used.

The paper describes aspects of colour 3D printing for which the published research and literature data are still, for the most part, lacking. Colour measurements methodology and evaluation of stability described could be of value for further research and for users of the technology.

In many industrial applications, convection radiation and conduction participate simultaneously to the heat transfers. A numerical approach able to cope with such problems has been developed. The code SYRTHES is tackling conduction and radiation (limited to non participating medium). Radiation is solved by a radiosity approach, and conduction by a finite element method. Accurate and efficient algorithms based on a mixing of analytical/numerical integration, and ray tracing techniques are used to compute the view factors. The fluid part is solved by CFD codes like ESTET (Finite volumes) or N3S (Finite elements). SYRTHES relies on an explicit numerical scheme to couple all the phenomena. No stability problems have been encountered. To provide further flexibility, the three phenomena are solved on three independent grids. All data transfers being automatically taken care of by SYRTHES. Illustrating applications are shown.

This paper presents an improved nine node Mindlin plate element. An enhanced interpolation of the transverse shear strains is used in this formulation of the new element which has the requisite number of zero energy modes, does not lock and passes the appropriate patch tests exactly. Some examples are included to illustrate the accuracy of the proposed element. The new 9‐node element is compared with the Lagrangian and heterosis elements and the general performance of the new element is much better than the other quadratic elements especially for shear force distributions.

A quadrilateral 2‐D finite element for linear and non‐linear analysis of solids is presented. The element is based on the technique of mixed interpolation of tensorial components. It is shown that the new element is reliable and efficient, being apt, therefore, to be used in routine engineering applications.