Analysis of an Integrated Agro-waste Gasification and 120 kW SOFC CHP System: Modeling and Experimental Investigation

Abstract Renewable sources of hydrogen are of major interest in the context of energy production through fuel cells. The technical feasibility of CHP system composed by orange peels steam/air gasification unit coupled with a solid oxide fuel cell (SOFC) was investigated in this study. To this purpose, a zero-dimensional process simulation model of the CHP system using Aspen Plus was developed. Mathematical model was experimentally validated in a lab scale apparatus. Moreover, optimal operative conditions and integration options were investigated, as well as the system maximum theoretical overall efficiency. Results showed that in order to obtain 120 kW of DC power from the specific SOFC, 65 kg/h of biomass with 20% of moisture and 173 kg/h of raw biomass with 70% of water needed to be fed in the CHP system. It was theoretically proved that 120 kW of DC power and 135 kW of heat could be produced from SOFC unit at the selected operative conditions, with a net CHP maximum efficiency equal to 74%

Visual perceptual learning is effective in the illusory far but not in the near space

Visual shape discrimination is faster for objects close to the body, in the peripersonal space (PPS), compared to objects far from the body. Visual processing enhancement in PPS occurs also when perceived depth is based on 2D pictorial cues. This advantage has been observed from relatively low-level (detection, size, orientation) to high-level visual features (face processing). While multisensory association also displays proximal advantages, whether PPS influences visual perceptual learning remains unclear. Here, we investigated whether perceptual learning effects vary according to the distance of visual stimuli (near or far) from the observer, illusorily induced by leveraging the Ponzo illusion. Participants performed a visual search task in which they reported whether a specific target object orientation (e.g., triangle pointing downward) was present among distractors. Performance was assessed before and after practising the visual search task (30 minutes/day for 5 days) at either the close (near group) or far (far group) distance. Results showed that participants that performed the training in the near space did not improve. By contrast, participants that performed the training in the far space showed an improvement in the visual search task in both the far and near spaces. We suggest that such improvement following the far training is due to a greater deployment of attention in the far space, which could make the learning more effective and generalize across spaces

Visual perceptual learning is enhanced by training in the illusory far space (abstract only)

Objects’ shape discrimination is faster for objects closer to the body (peripersonal space, PPS) compared to objects far from it. The closeness advantage has been observed for both low-level (size, orientation) and high-level (face identification) visual features, recent evidence supporting body centred perception of multisensory stimulation in PPS, namely a better performance when stimuli are near the body. However, it is unclear how PPS influences visual learning. In a series of studies, we investigated whether visual perceptual learning differs according to the depth dimension (near or far from the observer). Depth perspective was created using the “Ponzo Illusion”, the effect of the illusion on learning was also examined. Participants performed a visual search task in which they reported whether a specific target object orientation (e.g., triangle pointing downward) was present amongst distractors. The task was performed before and after a training phase. This phase consisted in a visual search task in the near (half of the participants) or far space and lasted about 3 (Study 1) or 1.5 (Study 2) hours. Results showed that the learning was specific for the orientation of the target and position (near or far) in space with a more prominent improvement for the far space. These findings suggest that different learning processes may be specifically associated to different sectors of space

Effects of visual and tactile training on motor behaviour

Human sensory abilities are crucial for interaction with the environment. It is known that the way we perceive the world through our senses can be improved following training. Sensory training and motor behaviour have been widely investigated, however, the direct effect of an improved sensory ability on motor behaviour is not clearly understood. In the visual domain, it has been shown that visual perception is affected by the space in which the stimuli are presented, with a better performance when stimuli are near (peripersonal space) compared to far (extrapersonal space) from our body. In the tactile domain, it has been shown that tactile training is an effective procedure to improve spatial acuity, however, there is contrasting evidence regarding whether such improvement is affecting motor behaviour. The role of visual and tactile training and their effects in space and on motor behaviour are investigated through two lines of research. The first line of research investigated the effectiveness of visual training when stimuli are presented near compared to far from the body. Surprisingly, we found that, differently from what happens in visual perception, visual training is more effective in the far compared to the near space. We suggest that such an effect is possibly due to greater deployment of attention in the far space, which could make the learning more impactful and generalisable across spaces. The second line of research explored the effect of passive tactile training (Repetitive Somatosensory Stimulation) applied to a finger, on hand motor behaviour and corticospinal excitability. Results revealed that passive tactile training affects the performance in a tactile task and in turn, modulates motor behaviour. Overall, this research provides new insights regarding the efficacy of visual perceptual learning in space (peripersonal vs extrapersonal) and the potential role of tactile passive training in altering motor behaviour

Visual perceptual learning near and far from the body

Objects’ shape discrimination is faster for objects closer to the body (peripersonal space, PPS) compared to objects far from it. The closeness advantage has been observed for both low-level (size, orientation) and high-level (face identification) visual features, recent evidence supporting body-part centred learning of multisensory stimulation in PPS. However, it is unclear how PPS influences visual learning. Here, we aim to investigate whether visual perceptual learning differs according to the depth dimension (near or far from the observer). Depth perspective was created using the “Ponzo Illusion”, the effect of the illusion on learning was also examined. Participants performed a visual search task in which they reported whether a specific target object orientation (e.g., triangle pointing downward) was present amongst distractors. The task was performed before and after a training phase. This phase consisted in a visual search task in the near (half of the participants) or far space and lasted about 3 hours. Results showed that the learning was specific for the orientation of the target and position (near or far) in space with a more prominent improvement for the far space. These findings suggest that different learning processes may be specifically associated to different sectors of space

Visual perceptual learning is effective in the illusory far but not in the near space

International audienceAbstract Visual shape discrimination is faster for objects close to the body, in the peripersonal space (PPS), compared with objects far from the body. Visual processing enhancement in PPS occurs also when perceived depth is based on 2D pictorial cues. This advantage has been observed from relatively low-level (detection, size, orientation) to high-level visual features (face processing). While multisensory association also displays proximal advantages, whether PPS influences visual perceptual learning remains unclear. Here, we investigated whether perceptual learning effects vary according to the distance of visual stimuli (near or far) from the observer, illusorily induced by leveraging the Ponzo illusion. Participants performed a visual search task in which they reported whether a specific target object orientation (e.g., triangle pointing downward) was present among distractors. Performance was assessed before and after practicing the visual search task (30 minutes/day for 5 days) at either the close (near group) or far (far group) distance. Results showed that participants that performed the training in the near space did not improve. By contrast, participants that performed the training in the far space showed an improvement in the visual search task in both the far and near spaces. We suggest that such improvement following the far training is due to a greater deployment of attention in the far space, which could make the learning more effective and generalize across spaces

Visual perceptual learning is effective in the far but not in the near space

Visual shape discrimination is faster for objects close to the body, in the peripersonal space (PPS), compared to objects far from the body. Visual processing enhancement in PPS occurs also when perceived depth is based on 2D pictorial cues. This advantage has been observed from relatively low-level (detection, size, orientation) to high-level visual features (face processing) (Ahsan et al., 2021; Dureux et al., 2021). While multisensory association also displays proximal advantages (Zanini et al., 2021), whether PPS influences visual perceptual learning remains unclear. Here, we investigated whether perceptual learning effects vary according to the distance of visual stimuli (near or far) from the observer, illusorily induced by leveraging the Ponzo illusion. Participants performed a visual search task in which they reported whether a specific target object orientation (e.g., triangle pointing downward) was present among distractors. Performance was assessed before and after practicing the visual search task (30 minutes/day for 5 days) at either the close (near group) or far distance (far group). Results showed that participants that performed the training in the near space did not improve. By contrast, participants that performed the training in the far space showed an improvement in the visual search task in both the far and near spaces. We suggest that such improvement in the far training is due to a greater deployment of attention in the far space, which could make the learning more effective and generalize across spaces

Somatosensory impact on motor cortex: how touch shapes motor behaviour

The ability to manipulate objects is a critical skill for humans. Such function is carried out primarily by the motor system. However, such a process would not be possible without the continuous information provided by the somatosensory system. The somatosensory feedback is particularly important when a movement must be adjusted while performing an action. Effective interactions between the somatosensory and motor systems are paramount for performing fine motor behaviour, as made dramatically clear by brain damage. Somatosensory deficits following nervous system lesions have received little attention compared to motor control. Yet, patients suffering from somatosensory deficits usually show reduced recovery of motor functions, preserved somatosensation being a good predictor of motor recovery. Despite the importance of touch in shaping motor behaviour, the functional relationships between the somatosensory and motor systems remain unclear. Here we examine the potential role of somatosensory information in modulating motor behaviour. We focus on a series of empirical studies that investigated the crosstalk between the somatosensory and motor systems, specifically on the role of touch in shaping motor behaviour. We will start by describing, across different species, the anatomical and neurophysiological connections between these systems and the nature of these communications. We will then present evidence from neuropathological studies and the severe consequences of somatosensory signals’ disruption on motor performance. Finally, we will examine the impact of short- and long-term tactile learning on the motor system as a promising approach for developing novel somatosensory-to-motor rehabilitation strategies, for people suffering from brain injury and other neurological conditions