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The development of machines explores the development of a manufacturing system. This perspective offers challenges adjacent to the materials, the product that wants to be manufactured, the technical considerations that must be covered during implementation and the manner of delivering the products to the user. This article addresses the design and development of machines, on the one hand the redesign of a multifunctional platform, and on the other hand a 3D food printer. The second is emphasised, since its main objective is to help the food problems that exist today. The design phases, aspects considered for its implementation such as food safety, the choice of the substrate, the functionality of the food, transportation and the pre- and post-processes required. In this manner, the selection and innovation of materials constitutes a primary source of innovation and research in the integral development of a 3D food printer. The main source of value of these both cases lie in customisation. The experiences of a multidisciplinary research team in the development processes are compiled and the design and creation process are shown, in order to contribute to deal with design and development to tackle fundamental problems of society. [ABSTRACT FROM AUTHOR]

This study presents the development of an event-driven hybrid control for position and force tracking applied on a mobile robotic manipulator for metal recycling tasks. The suggested controller operates in a sequenced strategy starting from a fixed spot, moving the mobile device towards a targeted zone ($\Omega _i^r$ Ω i r ) from where the i-th piece-to-be-recycled is attainable (considering the arm manipulation). Once the event of entering the zone is completed, the mobile robot is fixed at a position, and the end-effector of the robotic arm is enforced towards the piece-to-be-recycled. When the end-effector touches the piece in a given spot ($\Omega _i^e$ Ω i e ), the hybrid control changes to the force tracking intending to carry the piece towards the spot ($\Omega _i^p$ Ω i p ) where it ill be processed. Each piece location is identified based on a vision-based system that applies deep learning tools using convolutional neural networks. A multi-physics numerical simulation illustrated the application of the developed controller in a realistic scenario, showing all the elements of the event-driven operation. To validate the suggested controller, the comparison with a robust control that works on a wide range of carrying mass confirms the operational improvement of the event-driven hybrid position and force design. [ABSTRACT FROM AUTHOR]

Vehicle safety relies on the capacity of vehicle systems to decrease the likelihood of biomechanical injuries to both vehicle occupants and pedestrians. This can take the form of active or passive measures applied to the materials and their geometry in the event of an impact. Nevertheless, due to the nonlinear behaviour of materials and deformation, a distinct collapse process emerges that requires analysis; this analysis can be virtual or through experimental tests. While observed performance can be ascertained through experimental designs, executing such a design for every parameter combination can be time-consuming and costly. This study employs a Long Short-Term Memory (LSTM) to predict the energy absorbed and crushing force of thin-walled aluminium 6063 T5 tubes subject to different collapse triggers and heat treatments. The LSTM model is constructed using experimental data derived from experiments that consider trigger shape, area, trigger position, furnace duration, cooling temperature, and heat treatment soaking method. The LSTM model achieved a Root Mean Square Error (RSME) of 0.56 and 0.0025 for crushing force and energy absorption, respectively. LSTM proves to be a valuable tool for predicting results in nonlinear analysis, particularly in the context of crush behaviour. Also, a comparison of the LSTM and finite element analysis (FEA) predictive performance is presented. [ABSTRACT FROM AUTHOR]

A drum boiler is the most critical part of power generation plants. The control of a highly nonlinear, multiple input and multiple output drum boiler system (DBS) is a challenging task. In this work super-twisting sliding mode controllers (STSMCs) are designed for the control-oriented model of the DBS, which maintain a desired water level and pressure of the drum. The unknown state of the DBS required for the control design is estimated using a gain-scheduled Utkin observer (GSUO). A rigorous mathematical analysis is also included to show that the closed-loop system is locally stable. The simulation results show that the closed-loop system yields the required performance even in the presence of parametric uncertainty, process and measurement noises, and external disturbance. To make a fair comparison, a quantitative analysis is also carried out for STSMC and PI controllers. Both controllers consume similar control energy, but STSMC shows better tracking performance. [ABSTRACT FROM AUTHOR]

This manuscript proposes the design of a speech synthesis algorithm based on measured electroencephalographic (EEG) signals previously classified by a class of neural network with continuous dynamics. A novel multilayer differential neural network (MDNN) classifies a database with the EEG studies of 20 volunteers. The database contains information described by input-output pairs corresponding to EEG signals and a corresponding word imagined by the volunteer. The suggested MDNN estimates the unknown relationship between the information instances and suggests the most-likely word that the user wants mentioning. The proposed MDNN satisfactory classifies over 95% a set of words obtained from the suggested EEG study in which, the users have to watch four different geometric figures on a screen. [ABSTRACT FROM AUTHOR]

The removal of phenol compounds (such as phenol (Ph), 4-chlorophenol (4-CPh), and 4-phenolsulfonic acid (4-APS)) was studied using catalytic ozonation and cerium oxide (CeO2) as the catalyst. Conventional ozonation removes 40% and 30% of total organic carbon (TOC) for 4-CPh and 4-APS, respectively. The presence of the catalyst doubled the TOC removal in comparison with ozone alone. Chloride and sulfate ions, detached from the target compounds, did not affect the mineralization degree. The effect of ions was studied by adding NaCl and Na2SO4 during the ozonation of Ph with CeO2 as a catalyst. The O3-CeO2 process was responsible for 89% TOC removal, while the presence of NaCl and Na2SO4 decreased TOC removal by nearly 50%. Ozonation alone only removed 20% of TOC at 120 min with or without inorganic salts. The presence of salts in the Ph ozonation provoked in detrimental effect in comparison when inorganic ions were produced along with the decomposition of 4-CPh and 4-APS. [ABSTRACT FROM AUTHOR]

This paper uses a multi-head neural transformer to present the text-to-text translation/interpretation of Sign Language (SL) in the context of glosses (written SL). A Spanish to Mexican Sign Language (MSL) gloss dataset was built based on simple and compound sentences and the corresponding interpretation in MSL gloss. The interpretation process was achieved by implementing state-of-the-art tools in the natural language processing (NLP) field called neural transformers. We tried different architectures, varying the number of encoder-decoder layers and hyperparameters. The best of our models achieved 0.68 BLEU in the training phase and 0.33 in the validation phase. MSL glosses are crucial as they rule the grammatical order in which MSL has to be executed. All these quantitative and qualitative results confirm the potential applicability of neural transformers to create effective automatic translators for the Spanish language to MSL, with similar effectiveness shown by other automatic translators for other more likely languages. [ABSTRACT FROM AUTHOR]

The design of a state feedback and robust controller for regulating the tridimensional (3D) movement of autonomous underwater mobile crafts (AUMCs). The controller design is based on the application of Averaged Sub-Gradient Integral Sliding Mode Realisation (ASGISMR). The application of the ASGISMR yields the solution of the closed-loop extreme seeking control for a non-strictly convex functional depending on the tracking error between reference and 3D position of the AUMC. The design of reference trajectories was proposed to enforce the AUMC to follow a continued submersion and ellipsoidal detouring. The mechanical dynamical form of AUMC is well posed for applying the extended version of ASGISMR, considering that integral term represents an ASG associated to the euclidean norm of the tracking error. The time evolution of the functional over the controlled trajectories of the AUMC is compared with the corresponding functional enforced by a traditional state feedback controller with gravity effect compensation. The proposed controller exhibits better tracking and similar control magnitude than the considered reference state feedback realisation. These outcomes justify the potential contributions of the suggested ASGISMR to obtain the local minimisation of the evaluated functional, considering such controller as an extreme seeking realisation for the proposed AUMC. [ABSTRACT FROM AUTHOR]

The current study presents the treatment of water contaminated with the dye Direct Red 28 in the presence of Na2SO4 at three different concentrations (10, 40 and 80 g/L) by simple ozonation. This wastewater treatment was considered in a wastewater recycling process. At the end of each ozonation cycle, ozonation dynamics, ozone consumption, pH, electrical conductivity and UV/Vis spectra variation were analyzed and correlated with the stoichiometric analysis balance. The efficiency of the wastewater treatment in each reuse cycle was evaluated by a novel image processing method. The image results show that the presence of sulfate improves more than 45% the dye fixation on a cotton sample. However, at high additive concentrations, the color quality decreases 25%, compared with the system with low additive concentration, due to the presence of peroxysulfate ions and the compounds accumulated through the ozonation process. [ABSTRACT FROM AUTHOR]

This paper proves the ultimately boundedness analysis for the trajectory tracking problem between the states of an uncertain nonlinear system represented by a Takagi–Sugeno (T–S) system and a given set of desired trajectories. The design of an output feedback controller includes a weighted contribution of the models included in the T–S design. The proposed T–S fuzzy estimates the state variables based on the output information, exclusively. The output-based controller design uses a time-dependent Lyapunov function yielding the characterisation of ultimate boundedness for the trajectory tracking error. Sufficient conditions are obtained to ensure the existence of positive-definite solutions for two coupled time-varying matrix Riccati equations, which are needed to solve the tracking problem. A simplified scheme determines the gains for the feedback controller and observer. The proposed control law solves the trajectory tracking of an autonomous underwater vehicle. In this case, numerical solutions show that the controller forced the convergence of the tracking error after 2.0 seconds. An alternative control design approach based on linear matrix inequalities (LMI) is used for comparison purposes. The suggested controller forces a faster convergence of the tracking error than the LMI-based one and provides a smaller ultimate bound. [ABSTRACT FROM AUTHOR]

This study focuses in the output feedback stabilisation of constrained linear systems affected by uncertainties and noisy output measurements. The system states are restricted inside a given polytope and a classical Luenberger observer is used to reconstruct the unmeasurable states from output observations. Based on the observed states, a state feedback is proposed as the control input. The stability analysis and the control design are done using an extended version of the attractive ellipsoid method (AEM) approach. To avoid the violation of state constraints, this work proposes a barrier Lyapunov function (BLF) based analysis. The control parameters are obtained throughout the solution of some optimisation problems such that the BLF ensures an approximation of the constraints by a maximal ellipsoidal set and the AEM provides the characterisation of a minimal ultimately bounded set for the closed-loop system solutions. Numerical simulations show the advantages using the BFL-AEM methodology against classical sub-optimal controllers in academic second order and third order examples. Then, the proposed control strategy is applied over a Buck DC-DC converter. In all the cases, the method proposed here prevails over the other controllers. [ABSTRACT FROM AUTHOR]

In this work, the degradation of terephthalic acid (TA) by vanadium oxide (VxOy) supported on zinc oxide (ZnO) was evaluated in a photocatalytic ozonation treatment based on two UV-A LEDs distributions. TEM analysis and specific surface area measurement suggest that VxOy is not supported on ZnO, while the EDXRF and XPS analysis indicated the presence of VxOy. The XPS analysis on VxOy/ZnO catalyst showed non-significant surface change between fresh and used catalyst. However, ozone decomposition showed a higher reaction rate constant for catalytic (230%) and photocatalytic ozonation (310%) in comparison with single ozone treatment. Photocatalytic ozonation with central and external irradiation arrays was evaluated in TA elimination by a kinetic study. The irradiation arrays had not statistical differences in the TA decomposition or oxalic acid formation. These results suggest that the construction of central bodies inside the reactor could be not necessary for photocatalytic processes. [ABSTRACT FROM AUTHOR]

This study presents the treatment of wastewater contaminated with Reactive Black 5 (RB5) by simple ozonation in the presence of Na2SO4, Na2CO3 (inorganic additives), and their mixture. This oxidative treatment was a single step into a wastewater recycling process. At the end of each recycle, pH variation and UV/Vis spectroscopy of the ozonated samples were analyzed. The absorbency variations were correlated with the dynamics of ozone consumption after each recycle. The quality of the treated wastewater was evaluated by the dye fixation on cotton textile samples after each cycle. The quality of dyeing process was evaluated by a novel image processing method. The image analysis results demonstrated that the mixture of salts improved the fixation of dye after each of the eight recycling procedures. The presence of Na2SO4 favored the fixation of color and Na2CO3 catalyzed the reaction between dye and fiber. Moreover, the effect of Na2CO3 dominated the additives effect over the recycling ozonation of the RB5 dye. [ABSTRACT FROM AUTHOR]

This work reports the study of the decomposition of three PAHs (anthracene, phenanthrene, and fluorene) in aqueous solution at different pHs (2, 7, and 11) and in the presence of methanol as a co-solvent by two different methods: conventional ozonation (O3) and O3/activated carbon (AC). The results showed that without AC, the decomposition of anthracene and fluorene proceeded mostly by molecular O3 at pHs 2 and 7. The indirect ozonation mechanism expected at basic pH was inhibited by the presence of high concentrations of methanol, which acted as a radical scavenger. The ozone consumed by the radical formation under pH >7 induced a larger decomposition reaction rate (five times) for all PAHs at acidic and neutral conditions compared with the basic ones. The presence of AC modulated the decomposition rates for all PAHs at the pHs evaluated. The latter was confirmed by the similarity among the decomposition dynamics. [ABSTRACT FROM AUTHOR]

The aim of this work was to design a non-parametric model of interconnected systems represented by uncertain second-order systems with incomplete information (only the generalized position vector is measurable). Artificial neural networks appeared to be a plausible alternative to get a non-parametric representation of the aforementioned interconnected systems. The modelling strategy used a set of spatial distributed second-order continuous neural networks (CNN). Each node in the interconnected system was represented as a second-order continuous neural network added by the super-twisting discontinuous sliding mode algorithm. The non-parametric modelling problem was reduced to design a feasible expression for the CNN weights in order to reproduce the states (including the generalized derivative of position vector) of all the nodes dynamics together and simultaneously. The adaptive laws for the CNN weights ensured the convergence of the CNN trajectories to the states of the uncertain interconnected system. To investigate the qualitative behaviour of the suggested methodology, two numerical examples were proposed. The first one represents the interconnection of three mass–spring–damper mechanical systems. The second example considers the problem of the non-parametric modelling problem for a wave partial differential equation. A set of three-dimensional graphic representations were used to demonstrate the identification abilities achieved by the CNN designed in this study for the second case. [ABSTRACT FROM AUTHOR]

Physiological solutions ozonated are widely used in the medical field (dentistry and surgery) as an effective bactericide. In this investigation, the inactivation of Escherichia coli and Pseudomonas aeruginosa by ozone dissolved in physiological solution was studied. There is a poor knowledge of the inactivation efficiency of this solution for different bacteria. The efficiency of the microorganisms’ inactivation was evaluated by the total unsaturation of lipids measured by the so-called Double Bond Index (DB-index). This is a sensitive analysis to evaluate the quantity of carbon-carbon double bonds (>C=C<) available in organic and biological samples, with high efficiency and in a short time. DB-index results were compared with the quantity of colony forming units (CFU) available in the culture. Three experimental systems were evaluated to determine the relationship between the DB-index variable and the microorganism’s inactivation: 1) using BHI agar as a culture medium to evaluate the dynamic growing curve when the ozone dissolved was dosed over the strain’s surface; 2) using a glucose solution (5%) as culture media and keeping the ozone concentration constant, which was dissolved in different physiological solutions, to observe the effects of solvent type over the bacteria growth; and, 3) using a glucose solution (5%) as culture media, and physiological solution of NaCl (0.9%) as a dissolved media for ozone at different concentrations. From the experimental data, a model of the ozone inactivation of each pathogen was built to obtain the inactivation kinetics. The model obtained showed a correlation between the CFU behavior and DB-index to each bacteria, since Pseudomona aeruginosa was more resistant to being oxidized than Escherichia coli. [ABSTRACT FROM PUBLISHER]

In this study, a set of municipal wastewater (MWW) samples from an actual residual water treatment plant was treated by ozone. The residual water was characterized in terms of organic load and biological contaminants: total coliforms (TC), fecal coliforms (FC) and helminth eggs (HE). Initial values of these parameters were 2.8 × 107 MPN/100 mL, 8.48 × 106 MPN/100 mL, and 470 L−1, respectively. The experimental setup considered the modification of pH and ozone dose as independent variables. Three different initial pH values (4.0, 7.0, and 11.0) and three different ozone concentrations (6, 15, and 30 mg/L) were used to investigate the pH ozone dose effect. The efficiency of ozone-based treatment was determined by the reduction of the microbiological indicators (TC, FC, and HE) and physicochemical parameters (COD and turbidity). The response surface method was used to determine suboptimal reaction conditions. These conditions were obtained using a two-stage procedure. The conditions under which both microbiological and organics were better removed corresponded to pH 7.8 and ozone concentration of 15.5 mg/L. A decline of biological indicators of 99% for TC, 99% for FC, and 99% for HE was obtained under the same reaction conditions. The reduction of chemical oxygen demand (COD) and turbidity was 75% and 85% under the same operation conditions, respectively. [ABSTRACT FROM AUTHOR]

The removal of phenol compounds (such as phenol (Ph), 4-chlorophenol (4-CPh), and 4-phenolsulfonic acid (4-APS)) was studied using catalytic ozonation and cerium oxide (CeO2) as the catalyst. Conventional ozonation removes 40% and 30% of total organic carbon (TOC) for 4-CPh and 4-APS, respectively. The presence of the catalyst doubled the TOC removal in comparison with ozone alone. Chloride and sulfate ions, detached from the target compounds, did not affect the mineralization degree. The effect of ions was studied by adding NaCl and Na2SO4 during the ozonation of Ph with CeO2 as a catalyst. The O3-CeO2 process was responsible for 89% TOC removal, while the presence of NaCl and Na2SO4 decreased TOC removal by nearly 50%. Ozonation alone only removed 20% of TOC at 120 min with or without inorganic salts. The presence of salts in the Ph ozonation provoked in detrimental effect in comparison when inorganic ions were produced along with the decomposition of 4-CPh and 4-APS. [ABSTRACT FROM AUTHOR]