THE EFFECTS OF PHYSICAL FACTORS ON THE ADSORPTION OF SYNTHETIC ORGANIC COMPOUNDS BY ACTIVATED CARBONS AND ACTIVATED CARBON FIBERS

Activated carbons (ACs) and activated carbon fibers (ACFs) have been extensively used for the removal of synthetic organic compounds (SOCs) that have been found to be toxic, carcinogenic, mutagenic or teratogenic. Adsorption of these compounds on ACs and ACFs are controlled by both physical factors and chemical interactions, which depend on the characteristics of the adsorbent (surface area, pore size distribution (PSD), and surface chemistry), the nature of the adsorbate (molecular weight and size, functional groups, polarity, solubility), and the condition of the background solution (pH, temperature, presence of competitive solutes, ionic strength). Since there are several mechanisms that can affect the adsorption, it is important to understand the role of these individual factors responsible for the adsorption of a given combination of adsorbate and adsorbent under certain background conditions. The main objective of this study was to conduct a systematic experimental investigation to understand the effects of physical factors on the adsorption of SOCs by different porous carbonaceous adsorbents. Three ACFs, with different activation levels, and three granular activated carbons (GACs) produced from two different base materials were obtained, characterized and used in the experiments. The single solute adsorption isotherms of the selected carbons were performed for benzene (BNZ), biphenyl (BP), phenanthrene (PHE) and 2-hydroxybiphenyl (2HB). First, the role of carbon structure on the adsorption was examined and the accessible pore size regions for BNZ, BP and PHE were determined. It was found that adsorption of the selected SOCs was higher for ACFs than those of GACs due to the higher microporosity (more than 75%) and higher specific surface areas of ACFs. Both PSD and pore volume in pores less than 1 nm were important for the adsorption of BNZ, whereas accessible pore size regions for BP and PHE were determined to be approximately 1 - 2 nm. While adsorption of BNZ was found to be correlated with both surface areas and pore volumes, adsorption of BP and PHE was only related to the surface areas of carbons. These relationships showed that there was no restriction for BNZ molecules to access the pores of the carbons, whereas size exclusion effects were observed for BP and PHE adsorption. Second, the effects of the molecular structure, dimension and configuration of the selected SOCs were investigated. The adsorption uptake increased with decreasing molecular dimension of each compound, and the uptake was in the order of BNZ \u3e BP \u3e PHE for the six heat-treated carbons. The nonplanar BP had an advantage over the planar PHE, since it was more flexible, and thus, able to access deeper regions of the pores than the rigid PHE. It was observed that BP had higher adsorption capacities as expressed on mass-basis than those of 2HB at the same concentration levels. This was attributed to the different solubilities of these SOCs since they were very similar in molecular size and configuration. On the other hand, after their concentrations were normalized with solubility, at the same reduced concentration levels, the adsorption capacities of 2HB were higher than those of BP due to the π-π electron-donor-acceptor interactions that resulted from the hydroxyl group in the 2HB. Finally, to examine the role of surface oxidation, BP and 2HB adsorption isotherms on the heat-treated and oxidized ACFs were performed. The nitrogen adsorption data demonstrated that heat treatment increased the microporous surface areas by 2 to 13% compared to the oxidation of the ACF samples. Comparing the oxidized to the heat-treated ACFs, oxidized ACFs had higher oxygen and nitrogen contents and water vapor uptakes, which confirmed that they were more hydrophilic, than the heat-treated ACFs. Adsorption isotherm results demonstrated that the heat-treated ACFs had higher adsorption capacities than the oxidized ACFs, demonstrating that surface polarity had an important role in the adsorption of aromatic compounds

Can Real-time, Adaptive Human-Robot Motor Coordination Improve Humans’ Overall Perception of a Robot?

Previous research on social interaction among humans suggested that interpersonal motor coordination can help to establish social rapport. Our research addresses the question of whether, in a human-humanoid interaction experiment, the human’s overall perception of a robot can be improved by realising motor coordination behaviour that allows the robot to adapt in real-time to a person’s behaviour. A synchrony detection method using information distance was adopted to realise the real-time human-robot motor coordination behaviour, which guided the humanoid robot to coordinate its movements to a human by measuring the behaviour synchrony between the robot and the human. The feedback of the participants indicated that most of the participants preferred to interact with the humanoid robot with the adaptive motor coordination capability. The results of this proof-of-concept study suggest that the motor coordination mechanism improved humans’ overall perception of the humanoid robot. Together with our previous findings, namely that humans actively coordinate their behaviours to a humanoid robot’s behaviours, this study further supports the hypothesis that bidirectional motor coordination could be a valid approach to facilitate adaptive human-humanoid interaction.Peer reviewedFinal Accepted Versio

Interaction and Experience in Enactive Intelligence and Humanoid Robotics

We overview how sensorimotor experience can be operationalized for interaction scenarios in which humanoid robots acquire skills and linguistic behaviours via enacting a “form-of-life”’ in interaction games (following Wittgenstein) with humans. The enactive paradigm is introduced which provides a powerful framework for the construction of complex adaptive systems, based on interaction, habit, and experience. Enactive cognitive architectures (following insights of Varela, Thompson and Rosch) that we have developed support social learning and robot ontogeny by harnessing information-theoretic methods and raw uninterpreted sensorimotor experience to scaffold the acquisition of behaviours. The success criterion here is validation by the robot engaging in ongoing human-robot interaction with naive participants who, over the course of iterated interactions, shape the robot’s behavioural and linguistic development. Engagement in such interaction exhibiting aspects of purposeful, habitual recurring structure evidences the developed capability of the humanoid to enact language and interaction games as a successful participant

Geometric Reinforcement Learning For Robotic Manipulation

Reinforcement learning (RL) is a popular technique that allows an agent to learn by trial and error while interacting with a dynamic environment. The traditional Reinforcement Learning (RL) approach has been successful in learning and predicting Euclidean robotic manipulation skills such as positions, velocities, and forces. However, in robotics, it is common to encounter non-Euclidean data such as orientation or stiffness, and failing to account for their geometric nature can negatively impact learning accuracy and performance. In this paper, to address this challenge, we propose a novel framework for RL that leverages Riemannian geometry, which we call Geometric Reinforcement Learning (G-RL), to enable agents to learn robotic manipulation skills with non-Euclidean data. Specifically, G-RL utilizes the tangent space in two ways: a tangent space for parameterization and a local tangent space for mapping to a nonEuclidean manifold. The policy is learned in the parameterization tangent space, which remains constant throughout the training. The policy is then transferred to the local tangent space via parallel transport and projected onto the non-Euclidean manifold. The local tangent space changes over time to remain within the neighborhood of the current manifold point, reducing the approximation error. Therefore, by introducing a geometrically grounded pre- and post-processing step into the traditional RL pipeline, our G-RL framework enables several model-free algorithms designed for Euclidean space to learn from non-Euclidean data without modifications. Experimental results, obtained both in simulation and on a real robot, support our hypothesis that G-RL is more accurate and converges to a better solution than approximating non-Euclidean data.Comment: 14 pages, 14 figures, journa

Automatic Emotion Recognition in Children with Autism: A Systematic Literature Review

© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).The automatic emotion recognition domain brings new methods and technologies that might be used to enhance therapy of children with autism. The paper aims at the exploration of methods and tools used to recognize emotions in children. It presents a literature review study that was performed using a systematic approach and PRISMA methodology for reporting quantitative and qualitative results. Diverse observation channels and modalities are used in the analyzed studies, including facial expressions, prosody of speech, and physiological signals. Regarding representation models, the basic emotions are the most frequently recognized, especially happiness, fear, and sadness. Both single-channel and multichannel approaches are applied, with a preference for the first one. For multimodal recognition, early fusion was the most frequently applied. SVM and neural networks were the most popular for building classifiers. Qualitative analysis revealed important clues on participant group construction and the most common combinations of modalities and methods. All channels are reported to be prone to some disturbance, and as a result, information on a specific symptoms of emotions might be temporarily or permanently unavailable. The challenges of proper stimuli, labelling methods, and the creation of open datasets were also identified.Peer reviewedFinal Published versio

Evaluation of Adult Cases of Visceral Leishmaniasis Reported in Turkey by Pool Analysis Method

Objective: In this study, we aimed to to emphasize that visceral leishmaniasis exists in Turkey, and to discuss its clinical and laboratory findings and therapeutic approaches by evaluating the adult cases reported from Turkey through a pool analysis