A Biological Inspired Cognitive Framework for Memory-Based Multi-Sensory Joint Attention in Human-Robot Interactive Tasks

One of the fundamental prerequisites for effective collaborations between interactive partners is the mutual sharing of the attentional focus on the same perceptual events. This is referred to as joint attention. In psychological, cognitive, and social sciences, its defining elements have been widely pinpointed. Also the field of human-robot interaction has extensively exploited joint attention which has been identified as a fundamental prerequisite for proficient human-robot collaborations. However, joint attention between robots and human partners is often encoded in prefixed robot behaviours that do not fully address the dynamics of interactive scenarios. We provide autonomous attentional behaviour for robotics based on a multi-sensory perception that robustly relocates the focus of attention on the same targets the human partner attends. Further, we investigated how such joint attention between a human and a robot partner improved with a new biologically-inspired memory-based attention component. We assessed the model with the humanoid robot iCub involved in performing a joint task with a human partner in a real-world unstructured scenario. The model showed a robust performance on capturing the stimulation, making a localisation decision in the right time frame, and then executing the right action. We then compared the attention performance of the robot against the human performance when stimulated from the same source across different modalities (audio-visual and audio only). The comparison showed that the model is behaving with temporal dynamics compatible with those of humans. This provides an effective solution for memory-based joint attention in real-world unstructured environments. Further, we analyzed the localisation performances (reaction time and accuracy), the results showed that the robot performed better in an audio-visual condition than an audio only condition. The performance of the robot in the audio-visual condition was relatively comparable with the behaviour of the human participants whereas it was less efficient in audio-only localisation. After a detailed analysis of the internal components of the architecture, we conclude that the differences in performance are due to egonoise which significantly affects the audio-only localisation performance.

Evaluation of the causes of flexible pavement failure; case study of Enugu/Port-Harcourt expressway

This study examined the causes of flexible pavement failure, taking the Enugu/Port-Harcourt expressway as a case study; to understand possible peculiarities. Chainages 101+400 and 125+925 were the most critical, having potholes of 500mm in depth; hence, soil samples were taken from these spots. The following tests were conducted: Particle size distribution, Atterberg limits, Permeability, Compaction, and California Bearing Ratio (CBR). The results obtained showed evidence of presence of clay in the subgrade; hence, concluding that the failure was mainly caused by poor soil material. From visual condition survey, it was noted that there were no drainages even at the critical paths of the alignment, and there was a significant proportion of Heavy Goods Vehicles (HGVs) which may not have been adequately considered during design.

Integration of practical supplemental measurements into bridge condition visual inspection grading

The reliability of condition assessment of bridges obtained from analysis of visual inspection data is always a big concern among structural engineers. It has been known that the condition grading of a bridge is very subjective and can convey limited information to the end user. To finalize and verify the reported condition grading, inspectors and bridge owners have mainly been relying on images. It has been known that the image observation may not be sufficient to address all kinds of problems associated with visual condition grading. The integration of practical supplemental measurements into condition grading as proposed in this paper will contribute to minimize the errors in visual inspection. Measurement of vehicle induced vibrations through wireless accelerometers can be used to determine the natural frequencies of the bridge that can be reported at each inspection. The change in frequencies can be an indication of deterioration in stiffness of bridge over the years. Taking concrete samples by chipping at the inspection site and analyzing them under scanning electron microscope (SEM) at the laboratory can be used to identify the current problems with concrete degradation. In this scope, the regular bridge inspection procedure with the proposed enhancements has been performed on field inspection of highway bridges in Turkey to determine the practicality of the quick supplemental measurements and to analyze the difference in grading of the three different inspectors with different level of experiences.

Cross-Modal Effect of Presenting Visual and Force Feedback That Create the Illusion of Stair-Climbing

Image therapy, which creates illusions with a mirror and a head mount display, assists movement relearning in stroke patients. Mirror therapy presents the movement of the unaffected limb in a mirror, creating the illusion of movement of the affected limb. As the visual information of images cannot create a fully immersive experience, we propose a cross-modal strategy that supplements the image with sensual information. By interacting with the stimuli received from multiple sensory organs, the brain complements missing senses, and the patient experiences a different sense of motion. Our system generates the sense of stair-climbing in a subject walking on a level floor. The force sensation is presented by a pneumatic gel muscle (PGM). Based on motion analysis in a human lower-limb model and the characteristics of the force exerted by the PGM, we set the appropriate air pressure of the PGM. The effectiveness of the proposed system was evaluated by surface electromyography and a questionnaire. The experimental results showed that by synchronizing the force sensation with visual information, we could match the motor and perceived sensations at the muscle-activity level, enhancing the sense of stair-climbing. The experimental results showed that the visual condition significantly improved the illusion intensity during stair-climbing.

Impact of surface contamination on elemental composition of Sanguinea (Pall.) leaves

The leaves of C. sanguinea Pall. have the potential to accumulate dust on the surface. As the fine dust particles contain various chemical elements (ChEs), we studied the ChE composition in the leaves with different degrees of dust contamination to assess the impact on assay results. The samples of C. sanguinea leaves collected in the Kemerovo region (Russia) were divided into two groups based on the visual condition of plant material: clean leaves and dust contaminated leaves. The total ash assay revealed higher ash content, exceeding pharmacopoeial standards in the dust contaminated group. Dust contaminated leaf samples demonstrated significantly higher concentrations of many ChE: Si, Fe, Al, Na, Ti, Ni, Zr, Cr, V, Pb, La, Ga, Y, Sc and Yb comparing to non-contaminated plant material. The values of potentially hazardous ChEs were significantly lower than the maximum levels specified for medicinal raw materials in all studied samples.

Effect of visual condition and physical activity on the plantar pressure distribution in adult and older women

The aging process causes changes in the physical and functional conditions, as well as in the foot structure and function. This study aimed to analyze the plantar pressure variation with respect to visual information and physical activity in adult and older women. This was a cross-sectional study that included 142 women (mean age of 67.8 years). Participants responded the anamnesis questionnaire, Mini Mental State Examination, and International Physical Activity Questionnaire. Plantar pressure was assessed using computerized baropodometry. Weight distribution was observed in semitandem positions for the right foot forward and then the left foot forward . Data analysis showed that foot type had no correlation with age (p = 0.37 right foot; p = 0.93 left foot) or level of physical activity (p = 0.28 right foot; p = 0.96 left foot). Moreover, plantar pressure variation showed no significant relationship with age (R2 = 0.2; p = 0.6). In conclusion, plantar pressure variation is not associated with the morphological foot type in women analyzed, as the visual condition did not generate plantar pressure variations when compared to its effect on the classification of plantar arches. Furthermore, level of physical activity was not associated with plantar pressure variation .

Impact of surface contamination on elemental composition of Crataegus sanguinea (Pall.) leaves

The leaves of C. sanguinea Pall. have the potential to accumulate dust on the surface. As the fine dust particles contain various chemical elements (ChEs), we studied the ChE composition in the leaves with different degrees of dust contamination to assess the impact on assay results. The samples of C. sanguinea leaves collected in the Kemerovo region (Russia) were divided into two groups based on the visual condition of plant material: clean leaves and dust contaminated leaves. The total ash assay revealed higher ash content, exceeding pharmacopoeial standards in the dust contaminated group. Dust contaminated leaf samples demonstrated significantly higher concentrations of many ChE: Si, Fe, Al, Na, Ti, Ni, Zr, Cr, V, Pb, La, Ga, Y, Sc and Yb comparing to non-contaminated plant material. The values of potentially hazardous ChEs were significantly lower than the maximum levels specified for medicinal raw materials in all studied samples.