Adaptive Devices Research Articles

The Utilization of a Damping Structure in the Development of Self-Adaptive Water-Lubricated Stern Bearings

A novel water-lubricated stern bearing damping structure with self-adaptive performance is proposed to meet the load-balancing and vibration-damping requirements of water-lubricated bearings. This innovative damping structure comprises an elastic element and a damping alloy layer. The elastic element facilitates the static and dynamic load sharing of the stern bearing, mitigates the edge effects, ensures even distribution of the contact pressure along the axial direction, and enhances the overall bearing performance. Consequently, it prolongs the service life of the bearing and minimizes friction-induced stimulation. The damping alloy layer effectively attenuates the transmission of shafting vibrations to the foundation through the bearing, optimizing the vibration transmission characteristics. Leveraging the finite element model, an in-depth analysis of the compensation capability of the turning angle and damping performance of the adaptive stern bearing was conducted. The findings reveal that when the thickness of the elastic element is increased from 10 mm to 40 mm, the maximum contact pressure can be reduced by 12.53%. When the length ratio of the elastic element is reduced from 0.7 to 0.4, the maximum contact pressure is reduced by 12.42%. Therefore, increasing the thickness and decreasing the length of the elastic element in the adaptive damping device enhance the load performance, improve the compensation capabilities, and reduce the bearing wear, thereby promoting greater bearing uniformity. Furthermore, the adaptive vibration-damping device optimizes the vibration transmission characteristics from the propeller stimulation to the bearing node. The computational results demonstrate a noteworthy reduction in the speed, acceleration, and displacement responses at the first-order natural frequency, decreasing by 58.82%, 58.90%, and 58.86%, respectively. This substantial reduction in the vibration response at the first-order natural frequency signifies the effective mitigation of vibrations in the system.

Design of a soft sensor based on silver-coated polyamide threads and stress-strain modeling via Gaussian processes

The demand for reliable and efficient soft sensors has grown exponentially with the evolution of wearable devices and smart textiles. However, existing soft sensors often face challenges related to hysteresis, noise, and accuracy, hindering their seamless integration into practical applications. Our research presents a pioneering stress–strain soft sensor model based on silver-coated polyamide threads, augmented with additional silicone and graphite coatings for enhanced properties. Specifically, the silicone coating proves instrumental in elevating the sensor’s gauge factor and reducing noise, resulting in heightened accuracy. The extensive data analysis reveals the presence of hysteresis and non-linearities; however, our data exhibits remarkable robustness, as indicated by the high Spearman correlation coefficient values. In the context of system identification, a comparative analysis between traditional regression methods and Gaussian Process (GPs) Regression demonstrates the superior performance of GPs: this technique outperforms conventional regression techniques, obtaining 8.75 ± 4.06% Root Mean Square Error (RMSE) compared to the 12.70 ± 7.04% error observed in traditional methods. This research not only advances the field of soft sensor technology by developing an accurate, affordable and adaptable device, but also offers valuable insights into highly effective system identification techniques tailored for wearable devices.

Cassette recombination dynamics within chromosomal integrons are regulated by toxin-antitoxin systems.

Integrons are adaptive bacterial devices that rearrange promoter-less gene cassettes into variable ordered arrays under stress conditions, thereby sampling combinatorial phenotypic diversity. Chromosomal integrons often carry hundreds of silent gene cassettes, with integrase-mediated recombination leading to rampant DNA excision and integration, posing a potential threat to genome integrity. How this activity is regulated and controlled, particularly through selective pressures, to maintain such large cassette arrays is unknown. Here, we show a key role of promoter-containing toxin-antitoxin (TA) cassettes as systems that kill the cell when the overall cassette excision rate is too high. These results highlight the importance of TA cassettes regulating the cassette recombination dynamics and provide insight into the evolution and success of integrons in bacterial genomes.

A Low‐Cost Moderate‐Concentration Hybrid Electrolyte of Introducing CaCl2 and Ethylene Glycerol Enables Low‐Temperature and High‐Voltage Micro‐Supercapacitors

AbstractHigh‐concentration electrolyte effectively improves the energy density and anti‐freezing property of aqueous micro‐supercapacitors (MSCs), endowing them the opportunity serving as power sources for miniaturized electronics. However, the excessive usage of salt significantly increases the cost of the electrolyte. Herein, a cost‐effective moderate‐concentration hybrid electrolyte is designed by introducing CaCl2 and ethylene glycerol (EG) additives for low‐temperature and high‐voltage MSCs. The results manifest that the introduction of CaCl2 minimizes the number of water molecules with strong hydrogen bonds while the addition of EG can reduce the amount of H2O molecules in the primary solvation shell sheath of Ca2+ ion and strengthen the hydrogen bonds between EG and water molecules, thus endowing the optimal electrolyte with a wide electrochemical stability window of 3.5 V and a freezing point lower than −120 °C. Furthermore, the resulting hybrid MSCs offer a high voltage of 1.6 V, and realize 62% capacitance retention at −40 °C compared to that at room temperature. Moreover, The MSCs can endure 20000 cycles with 98.5% capacitance retention at −40 °C. This work provides a meaningful guidance for designing low‐cost moderate‐concentration hybrid electrolyte with wide electrochemical stability window and anti‐freezing property for intrinsically safe and environmentally adaptable devices.

Mutable Collagenous Tissue: A Concept Generator for Biomimetic Materials and Devices.

Echinoderms (starfish, sea-urchins and their close relations) possess a unique type of collagenous tissue that is innervated by the motor nervous system and whose mechanical properties, such as tensile strength and elastic stiffness, can be altered in a time frame of seconds. Intensive research on echinoderm 'mutable collagenous tissue' (MCT) began over 50 years ago, and over 20 years ago, MCT first inspired a biomimetic design. MCT, and sea-cucumber dermis in particular, is now a major source of ideas for the development of new mechanically adaptable materials and devices with applications in diverse areas including biomedical science, chemical engineering and robotics. In this review, after an up-to-date account of present knowledge of the structural, physiological and molecular adaptations of MCT and the mechanisms responsible for its variable tensile properties, we focus on MCT as a concept generator surveying biomimetic systems inspired by MCT biology, showing that these include both bio-derived developments (same function, analogous operating principles) and technology-derived developments (same function, different operating principles), and suggest a strategy for the further exploitation of this promising biological resource.

Imine-Linked 2D Conjugated Porous Organic Polymer Films for Tunable Acid Vapor Sensing.

Two-dimensional (2D) films of conjugated porous organic polymers (C-POPs) can translate the rich in-plane functionalities of conjugated frameworks into diverse optical and electronic applications while addressing the processability issues of their crystalline analogs for adaptable device architectures. However, the lack of facile single-step synthetic routes to obtain large-area high-quality films of 2D-C-POPs has limited their application possibilities so far. Here, we report the synthesis of four mechanically robust imine-linked 2D-C-POP free-standing films using a single-step fast condensation route that is scalable and tunable. The rigid covalently bonded 2D structures of the C-POP films offer high stability for volatile gas sensing in harsh environments while simultaneously enhancing site accessibility for gas molecules due to mesoporosity by structural design. Structurally, all films were composed of exfoliable layers of 2D polymeric nanosheets (NSs) that displayed anisotropy from disordered stacking, evinced by out-of-plane birefringent properties. The tunable in-plane conjugation, different nitrogen centers, and porous structures allow the films to act as ultraresponsive colorimetric sensors for acid sensing via reversible imine bond protonation. All the films could detect hydrogen chloride (HCl) gas down to 0.05 ppm, far exceeding the Occupational Safety and Health Administration's permissible exposure limit of 5 ppm with fast response time and good recyclability. Computational insights elucidated the effect of conjugation and tertiary nitrogen in the structures on the sensitivity and response time of the films. Furthermore, we exploited the exfoliated large 2D NSs and anisotropic optoelectronic properties of the films to adapt them into micro-optical and triboelectric devices to demonstrate their real-time sensing capabilities.

3D printing for Growth Adaptive Medical Devices: an alternative approach for craniosynostosis

An adaptive medical device is a piece of equipment designed to adjust or respond to changes in a patient’s condition or environment. The use of 3D printing technology for the development of adaptive medical devices has opened up new possibilities for customization, efficiency, and accessibility in healthcare. Sagittal craniosynostosis is a birth defect that arises due to a premature fusion of the sagittal suture in infants. This disease causes a misshapen skull and a rise of intracranial pressure that can lead to cognitive impairments. At six months of age, the preferred technique for craniosynostosis is an open vault remodeling surgery, an extremely invasive procedure with severe blood loss for the patient and significant postoperative pain. In this context, growth adaptive cranial plates, that can be tuned depending on the patient to achieve the desired skull shape through the deformation of the structure, can be a valid alternative. Cellular and lattice structures offer tailorable mechanical properties in relation to the designed geometry. Specifically, the geometry of cellular materials can be modified in relation to the final mechanical requirements. In this study, the predictability of the deformation of a PLA structure composed by honeycomb unit cells was studied performing compression simulations. The geometry was then modified, simulations and compression tests were then repeated in order to find an equation that could describe the relation between the internal angle of the honeycomb and the relative Poisson ratio. This relation can be further exploited for the production of customized adaptive devices for the treatment of sagittal craniosynostosis.

Https://rsisinternational.org/journals/ijriss/articles/challenges-in-supporting-visually-impaired-students-with-additional-disabilities/

This abstract explores the key barriers—communicational, technological, and attitudinal—that special educator face in accommodating children with visual impairment and additional disabilities under Samagra Shiksha Abhiyan. Communicational barriers arise due to the multifaceted needs of these children, requiring specialized methods such as braille, tactile aids, and adaptive communication strategies. However, the lack of adequate training and resources often hinders educators’ ability to effectively engage these students. Technological barriers further exacerbate the challenge, with insufficient access to and knowledge of assistive technologies like screen readers and adaptive devices limiting the support that can be provided. The rapid evolution of technology, coupled with financial and infrastructural constraints, leaves many educators struggling to keep pace with the tools necessary for inclusive education. Attitudinal barriers, stemming from societal biases and low expectations, significantly impact the educational experience of these children. Negative perceptions among educators, peers, and the broader community can lead to marginalization and inadequate support, undermining the inclusive goals of the program. Addressing these barriers is crucial for achieving the equitable educational opportunities envisioned by Samagra Shiksha Abhiyan. A focused approach that enhances training, improves technological access, and shifts attitudes towards inclusivity is essential for the full participation and success of children with visual impairments and additional disabilities. The accommodation of children with visual impairment and additional disabilities under Samagra Shiksha Abhiyan is fraught with significant challenges, particularly in terms of communicational, technological, and attitudinal barriers. Communicational barriers emerge as special educators struggle to address the complex needs of these students, who require specialized communication methods such as braille, tactile learning tools, and adaptive communication strategies. These methods are often not adequately supported by the existing infrastructure, and educators frequently lack the necessary training to implement them effectively. Technological barriers further compound the issue, with limited access to advanced assistive technologies such as screen readers, braille displays, and other adaptive devices. Even when these technologies are available, the rapid pace of advancement and the lack of proper training leave many educators unable to fully utilize them to support student learning. Attitudinal barriers represent another significant obstacle, as societal biases and misconceptions about the capabilities of children with multiple disabilities can lead to their marginalization. These attitudes, often reflected in the lower expectations of educators and the broader educational community, undermine efforts to provide a truly inclusive education. Addressing these barriers is crucial for realizing the goals of Samagra Shiksha Abhiyan and ensuring that all children receive the support they need to succeed in an inclusive educational environment.

Adaptive core cervical total disc arthroplasty device replicates biomechanical instantaneous center of rotation in cadaver model

Adaptive core cervical total disc arthroplasty device replicates biomechanical instantaneous center of rotation in cadaver model

Energy Consumption Monitoring and Prediction System for IT Equipment

This paper focuses on the monitoring and prediction of the energy consumption of IT equipment to make informed decisions in terms of energy efficiency. The challenge with current monitoring systems lies in their specialization, scalability and integration complexities. To overcome these challenges, we propose a monitoring and prediction system for energy consumption of IT equipment. The proposed solution combines an adaptable, cost-effiective and energy-Efficient embedded device with open source software and a service-oriented architecture (SOA), which offers flexibility and integration capabilities, facilitating the easy inclusion of several workstation working from different environments. Several traditional Linear Regression (LR) models were evaluated prediction models using a temporal window of hour taking into account several features. As a result of the LR models evaluation, it is established that the Bayesian Ridge model was the best model since it presented the lowest error and the highest coefficient of determination. Finally, two approaches were evaluated to predict energy consumption: a Kernel Density Estimation (KDE)-based mechanism proposed to generate predictor variables in order to predict future energy using the best LR model, and a KDE-based energy model. Numerical results show that the energy prediction using KDE for the energy measurements provides lower time response than the LR based mechanism for the available dataset.

Nanotechnology and Prosthetic Devices: Integrating Biomedicine and Materials Science for Enhanced Performance and Adaptability

Nanomaterials are revolutionizing prosthetic device development. Nanotechnology has made prosthetic devices that replicate natural limb behavior and respond to users’ intentions possible. Nanomaterials improve prosthetic functionality, comfort, and lifespan. Nanocomposites, smart sensors, and medication delivery systems have addressed mechanical strength, control, and biocompatibility, resulting in enhanced prosthetic devices that improve user freedom, mobility, and quality of life. Biomedicine and materials science have helped nanomaterials reach their full potential, enabling their seamless integration into prosthetic devices and fostering interdisciplinary collaborations that advance prosthetics. The literature study shows substantial advances in nanomaterials for prosthetic devices; however, various gaps in present research and possible future research areas are indicated. First, long-term biocompatibility studies are needed to understand nanomaterials’ long-term effects on humans. Nanomaterial-based prosthetic devices must be tested and researched to assure safety and efficacy in real-world situations. Second, nanocomposites and nanoscale components must be standardized and quality-controlled to enable consistency and scalability in prosthetic devices. Third, nanoscale sensor and neural interface ethics must address privacy, security, and user consent issues. The nanomaterial-based prosthetic devices must be made more inexpensive and accessible to more disabled people. The study design was carried out to incorporate significant literature on the application of nanotechnology related to prosthetic devices. The literature was filtered from the Scopus database. The selected literature belongs to the original articles in which experimental work was carried out. Future research could combine nanotechnology with other developing technologies like artificial intelligence and robotics to produce more advanced and adaptable prosthetic devices.

Prototype of a device adaptable to walk-sticks with a system to communicate the visible spectrum to blind people.

This project aims to design and build a device adaptable to canes for blind people that allows them to know the color of everyday objects through a tactile response. The prototype of the device identifies the colors by means of the TCS3200 color sensor that, when detecting the light reflected by the objects, converts it into an electrical signal to later process it with the Arduino Nano microcontroller and thus generate a tactile response using a servomotor. For this purpose, mechanical and electronic designs of the color recognition and representation systems using the Feelipa color code were developed, and a functional prototype of the adaptive device that identifies primary colors was developed. Algorithms for the classification of secondary colors from their RGB values continue to be developed, and the mechanical designs are being improved to take into account aesthetic and ergonomic aspects that facilitate their use

Open-source controller for dynamic cardiovascular models

Cardiovascular pressure sensors require dedicated, reliable, and customisable performance testing equipment. Devices available on the market, such as pulsatile pumps and pulse multipliers, offer limited adaptability to the needs of pressure sensor testing or are highly complex tools designed for other purposes. Therefore, there is a strong need to provide an adaptable and versatile device for characterisation during prototype development, prior to animal model testing. Early development requires detailed characterisation of a sensor performance in a realistic environmental scenario. To address this need, we adapted an off-the-shelf pressure chamber with a custom Arduino-based controller to achieve a rapid change in pressure that simulates the pulsatile profile of human blood pressure. The system is a highly customisable tool, and we have experimentally shown that it works successfully in a wide range of pressures from 30 mmHg to 400 mmHg with a resolution of 2 mmHg. By adjusting the chamber volume using a water balloon, we achieved a cycle rate of up to 120 beats per minute. The device can be operated directly from the Arduino IDE or with a customised graphical user interface developed by our research group. The proposed system is intended to assist other researchers in the development of industrial and biomedical pressure sensors.

Vaping product exposure system (VaPES): a novel in vitro aerosol deposition system

Objective Due to recent increases in the use of vaping devices, there is a high demand for research addressing the respiratory health effects of vaping products. Given the constantly changing nature of the vaping market with new devices, flavors, metals, and other chemicals rapidly emerging, there is a need for inexpensive and highly adaptable vaping device exposure systems. Here, we describe the design and validation of a novel in vitro aerosol exposure system for toxicity testing of vaping devices. Materials and methods We developed an inexpensive, open-source in vitro vaping device exposure system that produces even deposition, can be adapted for different vaping devices, and allows for experiments to be performed under physiological conditions. The system was then validated with deposition testing and a representative exposure with human bronchial epithelial cells (hBECs). Results The Vaping Product Exposure System (VaPES) produced sufficient and uniform deposition for dose-response studies and was precise enough to observe biological responses to vaping exposures. VaPES was adapted to work with both pod and cartridge-based vaping devices. Conclusion We have designed and validated a novel vaping device exposure system that will eliminate the need to use high-cost commercial exposure systems, lowering the barrier to entry of physiologically relevant vaping studies.

Climate Change and Fish Farming: Venetian “Fish Valleys” as a Design Device for Coastal Adaptation and Mitigation

Beginning in the fourteenth century, along the northeastern Italian coastline, Venetians began to create a series of hydraulic structures called “fishing valleys,” which combined aquaculture production with lagoon and seawater management. According to the current scenarios provided by the Intergovernmental Panel on Climate Change, the coastal areas, where many historic fish farms still stand, will inevitably be affected by the rise in sea level. To be preserved, they will require some sort of water defense or possibly a managed retreat. Can we redesign traditional fish-farm systems as climate, economic and environmental adaptation devices? Through a series of design scenarios, this contribution explores how traditional fish farming can help redefine the territorial scale by addressing climate change and reviving existing production systems.

Adaptive device sampling and deadline determination for cloud-based heterogeneous federated learning

As a new approach to machine learning, Federated learning enables distributned traiing on edge devices and aggregates local models into a global model. The edge devices that participate in federated learning are highly heterogeneous in terms of computing power, device state, and data distribution, making it challenging to converge models efficiently. In this paper, we propose FedState, which is an adaptive device sampling and deadline determination technique for cloud-based heterogeneous federated learning. Specifically, we consider the cloud as a central server that orchestrates federated learning on a large pool of edge devices. To improve the efficiency of model convergence in heterogeneous federated learning, our approach adaptively samples devices to join each round of training and determines the deadline for result submission based on device state. We analyze existing device usage traces to build device state models in different scenarios and design a dynamic importance measurement mechanism based on device availability, data utility, and computing power. We also propose a deadline determination module that dynamically sets the deadline according to the availability of all sampled devices, local training time, and communication time, enabling more clients to submit local models more efficiently. Due to the variability of device state, we design an experience-driven algorithm based on Deep Reinforcement Learning (DRL) that can dynamically adjust our sampling and deadline policies according to the current environment state. We demonstrate the effectiveness of our approach through a series of experiments with the FMNIST dataset and show that our method outperforms current state-of-the-art approaches in terms of model accuracy and convergence speed.

Electric field-induced anisotropy in the electronic properties of blue phosphorus/WSe2 heterojunction

In this study, first principle calculations was used to investigate the characteristics of a Blue P/WSe2 heterojunction. Among six potential stacking arrangements, the structure II was identified as the most energetically favorable. And interlayer spacing analyzing shown that a distance of 3.354 Å for the two-layer stack is the most stable configuration. The band structure results demonstrated that the heterojunction possesses an indirect bandgap of 1.12 eV utilizing HSE06 and 0.81 eV utilizing GGA. Upon accounting for spin-orbit effects based on GGA method, the indirect bandgap transforms into a direct bandgap of 1.34 eV. Notably, the valence band maximum (VBM) and conduction band minimum (CBM) mainly stem from P's p orbitals and W's d orbitals, respectively. Moreover, scrutiny revealed that W's d orbitals within WSe2 introduce a spin-orbit coupling-induced splitting of approximately 0.50 eV. By exploring the impact of an external electric field in various directions, strengths, and interlayer distances, it was found the electronic structure of the heterojunction can be manipulated. This capability leads to a broad spectrum of tunable bandgap values. Density of states and population analyses underscore the susceptibility of interactions between outer P and outer Se pz orbitals, to electric field influence. Our research findings have the potential implications for designing adaptable optical and electronic devices.

High-quality VO2 films synthesized on polymer substrates using room-temperature pulsed laser deposition and annealing

With the growing trend towards portable and adaptable devices in various fields, the demand for flexible electronics and coatings utilizing phase transition materials like VO2 as a functional layer is rising. However, depositing high-quality crystalline VO2 films directly onto polymer substrates remains challenging due to the thermosensitivity of such materials being barely compatible with usual VO2 deposition methods. In this study, we present a simple method for directly growing VO2 on Kapton substrates. VOx films were first deposited onto the Kapton substrate at room temperature using pulsed laser deposition and subsequently annealed in an oxygen atmosphere at 390 °C. The electrical and optical properties of the VO2/Kapton samples with different film thicknesses were investigated. The 200 nm-thick vanadium dioxide films exhibit the best resistivity contrast with 3.1 orders of magnitude (OOM), while the 50 nm-thick films show the best transmittance change of 54 % at 2500 nm. The switching performances are comparable or even superior to those achieved previously using more complicated synthesis processes such as film transfer, introduction of buffer layers, and ink injection. Additionally, by coupling W elemental doping and thin film strain, we successfully tuned the VO2 transition temperature to room temperature with a dopant concentration of only 1.1 at.% while maintaining a high electrical contrast (2 OOM). The impressive electrical and optical transition performance of the VO2/Kapton samples, combined with their tunable transition temperature, makes them promising candidates for flexible electronic devices and thermochromic smart coatings.

In vivo validation of a mechanically adaptive microfluidic intracortical device as a platform for sustained local drug delivery

Introduction: Intracortical microelectrodes (IME) are vital to properly functioning brain-computer interfacing (BCI). However, the recording electrodes have shown a steady decline in performance after implantation, mainly due to chronic inflammation. Compliant materials have been explored to decrease differential strain resulting in lower neural inflammation. We have previously developed a fabrication method for creating mechanically adaptive microfluidic probes made of a cellulose nanocrystal (CNC) polymer nanocomposite material that can become compliant after implantation. Here, we hypothesized that our device, would have a similar tissue response to the industry standard, allowing drug delivery therapeutics to improve neural inflammation in the future.Methods: RNA expression analysis was performed to determine the extent of neural inflammation and oxidative stress in response to the device compared to controls and to naïve shame tissue.Results: Results presented for both four- and eight-weeks post-implantations suggest that our device offers a promising platform technology that can be used to deliver therapeutic strategies to improve IME performance.

User-Informed Adaptation in IoT Home Healthcare: Grounding Development in Empirical Evidence

IoT (Internet of Things)-enabled products are increasingly used by consumers and continuously propagate in daily life. Billions of networked objects not only increase the complexity of development but also raise user interaction and adaptation to individual needs. The more non-expert users are involved in decision making, interaction, and adaptation processes, the more user-centric IoT design is crucial, particularly when the number of elderly users is steadily increasing. In this paper, we study the capabilities of adopting IoT products through user-informed adaptation in a major IoT application domain, home healthcare. We review evidence from established practice in the field on how users can be supported when aiming to adapt medical IoT (M-IoT) home applications to their needs. We examine the empirically grounded use of IoT sensors and actuators, as well as the adaptation process users adopt when using an IoT application in a personalized environment. Our analysis (technological evidence) reveals various IoT devices that have already been applied in M-IoT adaptation settings to effectively support users. Our analysis reveals that only few empirically sound findings exist on how users actually perceive interactive adaptation features and redesign M-IoT applications. Based on the analysis of these empirically grounded findings, we suggest the development of a domain-specific user-centric adaptation feature. Specifically, we exemplify a tangible adaptation device for user-informed M-IoT application in home healthcare. It has been developed prototypically and tested in an environment for personalized home healthcare.