Resonance-Assisted Hydrogen Bond—Revisiting the Original Concept in the Context of Its Criticism in the Literature

In the presented research, we address the original concept of resonance-assisted hydrogen bonding (RAHB) by means of the many-body interaction approach and electron density delocalization analysis. The investigated molecular patterns of RAHBs are open chains consisting of two to six molecules in which the intermolecular hydrogen bond stabilizes the complex. Non-RAHB counterparts are considered to be reference systems. The results show the influence of the neighbour monomers on the unsaturated chains in terms of the many-body interaction energy contribution. Exploring the relation between the energy parameters and the growing number of molecules in the chain, we give an explicit extrapolation of the interaction energy and its components in the infinite chain. Electron delocalization within chain motifs has been analysed from three different points of view: three-body delocalization between C=C-C, two-body hydrogen bond delocalization indices and also between fragments (monomers). A many-body contribution to the interaction energy as well as electron density helps to establish the assistance of resonance in the strength of hydrogen bonds upon the formation of the present molecular chains. The direct relation between interaction energy and delocalization supports the original concept, and refutes some of the criticisms of the RAHB idea.

Interaction Preference Differences between Elderly and Younger Exergame Users

Existing motion capture technology can efficiently track whole-body motion and be applied to many areas of the body. This whole-body interaction design has gained the attention of many researchers. However, few scholars have studied its suitability for elderly users. We were interested in exercise-based whole-body interactive games, which can provide mental and physical exercise for elderly users. We used heuristic evaluation to measure participants’ actions during exergame tasks and analyzed preference differences between elderly and younger users through the distribution of actions in four dimensions. We found that age affected the actions performed by users in exergame tasks. We discuss the mental model of elderly users during the process of performing these tasks and put forward some suggestions for interactive actions. This model and these suggestions theoretically have guiding significance for the research and application of exergame design for elderly users and may help designers develop more effective exergames or other whole-body interaction interfaces suitable for elderly users.

Investigation of the mathematical model of the knife of geokhod executive body interaction with the bottomhole rock

The article presents the relevance of the research. The features of the work of the executive body of geokhod are given. A previously developed mathematical model for determining the power and energy parameters of the interaction of the knife executive body of the geokhod with the face rock is presented. On the basis of the model, a study was carried out of the influence of the pitch of the external mover on the power and energy parameters of the interaction of the knife executive body of the geokhod with the bottomhole rock. As a result of the study, it was found that the power parameters increase with increase in the step of the external mover, and the energy parameters decrease.

Effect of the Opponent’s Appearance on Interpersonal Cognition that Affects User-to-User Relationship in Virtual Whole-Body Interaction

People infer the internal characteristics (attitude, intent, thoughts, ability, relationship, etc.) of others (interpersonal cognition, IC) from the impressions they form from the personality or attributes of those others (impression formation). Studies premised on interpersonal communication in a seated condition have confirmed that, regardless of whether the communication is in the real world or in a media environment, the appearance of the other person affects IC and the outcome of the communication. People also develop relationships based on impressions or images of the other party. The psychological relationship manifests in physical relationships, that is, the relative positions of the body or the movement. In this study, we evaluate the effects of the appearance of the opponent’s avatar on the players’ IC in whole-body interaction taking place in a virtual reality (VR) space. Moreover, we examine the feasibility of constructing a method of changing the players’ relationship in interpersonal interactions that accompany the control and interference of the entire body, “whole-body interaction,” by manipulating their appearances. In this study, we selected the party game Twister as a case model of whole-body interaction and developed a system that allows users to play Twister in VR space. Using this system environment, we conducted an experiment to evaluate the players’ IC based on the gender and realism of the opponent’s avatar. The results showed that differences in the appearance of the opponent’s avatar affected the IC of male players. We also indicated that changes in IC observed in the experiment can affect the players’ relationship, thus identifying issues that must be resolved in order to realize the method.

Haptic force rendering of rigid-body interactions: A systematic review

Haptic rendering has been developing for decades with different rendering approaches and many factors that affect the stability when rendering rigid-body interactions have been investigated. To get an overall understanding of the challenges in haptic rendering, we approach this topic by conducting a systematic review. This review examines different haptic rendering approaches and how to deal with instability factors in rendering. A total of 25 papers are reviewed to answer the following questions: (1) what are the most common haptic rendering approaches for rigid-body interaction? and (2) what are the most important factors for instability of haptic rendering and how to address them? Through the process of investigating these questions, we get the insight that transparency can be further explored and technical terms to describe haptic rendering can be more standardized to push the topic forward.

Wake-body interaction Noise Simulations by Coupling CFD and BEM

In many engineering applications, the wake-body interaction or body-vortex interaction (BVI) occurs. In the wake-body interaction, vortices shed from an upstream obstacle interact with downstream obstacle and generate noise, for example blades in a turbomachinery, tubes in a heat exchanger, rotating blades like a helicopter and wind turbine and so on. The rod-airfoil and airfoil-airfoil configurations are typical models for the wake-body interaction. A rod and an airfoil are immersed upstream of the airfoil. In this paper, we reviewed the noise mechanism generated by the wake-body interaction and show the numerical results obtained by the coupling method using commercial CFD and acoustic BEM codes. The results shows that depending on the spacing between the rod or airfoil and the airfoil, the flow patterns and noise radiation vary. With small spacing, the vortex shedding from the upstream obstacle is suppressed and it results in the suppression of the sound generation. With large spacing, the shear layer or the vortices shed from the upstream obstacle impinge on the downstream obstacle and it results in the large sound generation. The dominant peak frequency of the generated sound varies with increasing of the spacing between the two obstacles.