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The triboelectric nanogenerator (TENG) is a promising technology for self‐powered sensors and vibration‐driven energy harvesting, with its development especially influenced by the characteristics of tribomaterials. However, developing tribopositive materials with a strong cationic effect and high electron‐donating capability remains challenging. In this study, a novel polyethylene oxide@poly(diallyldimethylammonium chloride) (PEO@Poly‐DADMAC) composite nanofiber mat (NFM) is successfully fabricated using the electrospinning technique. It functions as a highly tribopositive material, particularly enhancing the performance of nanofiber‐based TENGs (NF‐TENGs). Through investigation of its physical and triboelectric properties, the study revealed that incorporating cationic Poly‐DADMAC with PEO effectively boosts NF‐TENG output by increasing the dielectric constant (twofold), electron‐donating affinities, and surface charge trapping capability. The fabricated NF‐TENG shows excellent output performance generating 980 V, a maximum power density of 5.6 Wm−2, and an ultrahigh sensitivity of 8.923 V kPa−1 which endows composite reliability for power supply and sensing capability. More importantly, the PEO@Poly‐DADMAC‐based self‐powered motion sensor with an NF‐TENG array is successfully demonstrated in multifunctional applications such as athlete activity tracking, and wireless gaming interface control. This study not only offers new insights into optimizing performance and selecting alternative tribomaterials but also provides valuable guidance for developing high‐output TENGs and highly sensitive self‐powered sensors. [ABSTRACT FROM AUTHOR]

The functionality and use of wearable triboelectric nanogenerators (TENGs) are significantly impacted by the development of their tribomaterial properties. Herein, a novel charge‐generating layer (CGL) composed of a V2CTx/Silicone nanocomposite and serpentine TENG (S‐TENG) is introduced. The V2CTx/Silicone nanocomposite exhibits a highly electronegative surface, which significantly enhances the surface potential and charge density. The fabricated nanocomposite‐based TENG exhibits a peak power density of 19.75 W m−2. It also exhibits a high mechanical stretchability (400%), which is significantly better than those of previously reported TENGs under small external pressure. The optimized S‐TENG is demonstrated as a self‐powered human motion sensor with high sensitivity (4.93 V kPa−1) and a quick rise time (21 ms). Furthermore, a real‐life demonstration of sign language interpretation using finger motion detection and text conversion via smartphones is successfully performed. Additionally, the real‐time sensing ability of the S‐TENG is demonstrated in virtual reality car games controlled by finger touch. The S‐TENG is demonstrated to capture different types of human motion energy for continuously powering a stopwatch and wristwatch. Therefore, it is expected that the V2CTx/Silicone nanocomposite will continue with the contributions of novel CGL materials for various TENG applications including wearable self‐powered sensors, robotics, and healthcare monitoring in IoT platforms. [ABSTRACT FROM AUTHOR]

The Schnakenberg model is thought to be the Caputo fractional derivative. A discretization process is first used to create caputo fractional differential equations for the Schnakenberg model. The fixed points in the model are categorized topologically. Then, we show analytically that a fractional order Schnakenberg model supports a Neimark-Sacker (NS) bifurcation and a Flip-bifurcation under certain parametric conditions. Using central manifold and bifurcation theory, we demonstrate the presence and direction of NS and Flip bifurcations. The parameter values and the initial conditions have been found to profoundly impact the dynamical behavior of the fractional order Schnakenberg model. Numerical simulations demonstrate chaotic behaviors like bifurcations, phase portraits, period 2; 4; 7; 8; 10; 16; 20 and 40 orbits, invariant closed cycles, and attractive chaotic sets in addition to validating analytical conclusions. To support the system's chaotic characteristics, we also quantitatively compute the maximal Lyapunov exponents and fractal dimensions. Finally, the chaotic trajectory of the system is stopped using the OGY approach, hybrid control method, and state feedback method. [ABSTRACT FROM AUTHOR]

Surface modification of triboelectric negative layers is an essential factor for boosting the output performance of triboelectric nanogenerators (TENGs). Herein, a novel scalable surface modification method is introduced using a fabric‐assisted micropatterning technique on a highly negative MXene/silicone nanocomposite surface (charge generating) with MXene layer (charge trapping) for self‐powered sensors and wearable electronics. The microstructured surface is fabricated directly from a fabric template requiring no surface‐active agent, high‐pressure equipment, or high vacuum. To boost the proposed double‐side‐contact TENG (DSC‐TENG) output performance, different parameters of the fabric textures are tested and optimized for the roughened microstructures, namely the MXene layer and relative humidity. Under optimal conditions, the fabricated DSC‐TENG improves the voltage and peak current density by factors of 9.8 and 20, respectively, regarding flat silicone. It exhibits a maximum peak power density of 55.47 W m−2 at load resistance of 0.18 MΩ, and a corresponding decrease in resistance by 75% using MXene content of 3 mg cm−2. Also, DSC‐TENG‐based smart home control of electrical appliances, theft protection, self‐powered electronic devices, password authentication, and human motion monitoring via smartphone for the IoT are demonstrated. The proposed method can be implemented for different types of polymers, thereby enabling the large‐scale fabrication of high‐performance TENGs in industrial applications. [ABSTRACT FROM AUTHOR]

The triboelectric material properties and mechanical stability of the contact layer are vital to achieving durable triboelectric nanogenerators (TENGs) with high output performance. Herein, a novel MXene/Ecoflex nanocomposite is introduced as a promising triboelectric material because of its highly negative triboelectric properties and mechanical stability. The MXene/Ecoflex nanocomposite with a fabric‐based waterproof TENG (FW‐TENG) is fabricated and designed to universally harvest energy from various human motions as well as the natural environment (rain and wind). The fabricated FW‐TENG delivers a maximum output peak power of 3.69 mW and a power density of 9.24 W m−2, respectively, at a matching load resistance of 4.5 MΩ under a frequency of 4.5 Hz and a force of 8 N. Furthermore, the applicability of this device in various products is investigated. The FW‐TENG can protect against a crash caused by rainy and humid weather. An FW‐TENG‐based self‐powered smart active device that detects motion on a carpet is demonstrated and is equipped with sleep monitoring motion sensors. The FW‐TENG not only has self‐powered benefits and excellent mechanical amenability but is also exceptionally reliable and stable against water intrusion, which are important characteristics to realize next‐generation wearable/portable technologies. [ABSTRACT FROM AUTHOR]

Internet of Things (IoT) opens new horizons by enabling automated procedures without human interaction using IP connectivity. IoT deals with devices, called things, represented as any items from our daily life that are enhanced with computing or communication facilities. Among various mobile communications, Zigbee communication is broadly used in controlling or monitoring applications due to its low data rate and low power consumption. Securing IoT systems has been the main concern for the research community. In this paper, different security threats of Zigbee networks in the IoT platform have been addressed to predict the potential security threats of Zigbee protocol and a Security Improvement Framework (SIF) has been designed for intelligent monitoring in an office/corporate environment. Our proposed SIF can predict and protect against various potential malicious attacks in the Zigbee network and respond accordingly through a notification to the system administrator. This framework (SIF) is designed to make automated decisions immediately based on real-time data which are defined by the system administrator. Finally, the designed SIF has been implemented in an office security system as a case study for real-time monitoring. This office security system is evaluated based on the capacity of detecting potential security attacks. The evaluation results show that the proposed SIF is capable of detecting and protecting against several potential security attacks efficiently, enabling a more secure way of intelligent monitoring in the IoT platform. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the dynamics of a discrete-time predator-prey system involving group defense. The existence and local stability of positive fixed point of the discrete dynamical system is analyzed algebraically. It is shown that the system undergoes a flip bifurcation and a Neimark-Sacker bifurcation in the interior of R2+ by using bifurcation theory. Numerical simulation results not only show the consistence with the theoretical analysis but also display the new and interesting dynamical behaviors, including phase portraits, period-7, 20-orbits, attracting invariant circle, cascade of period-doubling bifurcation from period-20 leading to chaos, quasi-periodic orbits, and sudden disappearance of the chaotic dynamics and attracting chaotic set. The Lyapunov exponents are numerically computed to characterize the complexity of the dynamical behaviors. [ABSTRACT FROM AUTHOR]

In this paper, we consider a classical discrete-time food chain model describing predators-prey interaction. The Holling type I functional response is used as the uptake for both predators. The existence and local stability of fixed points of the discrete dynamical system are analyzed algebraically. Using growth rate of prey as the bifurcation parameter, it is shown that the system undergoes a flip and Hopf bifurcations around planer or interior fixed point. It has been found that the dynamical behavior of the model is very sensitive to the parameter values and the initial conditions. Numerical simulations not only illustrate the key points of analytical findings but also exhibit complex dynamical behaviors of the model, such as the phase portraits, cascade of period-doubling bifurcation and determine the effects of operating parameters of the model on its dynamics. The Lyapunov exponents are numerically computed to characterize the asymptotic stability of the system dynamic response and estimate the amount of chaos in the system. [ABSTRACT FROM AUTHOR]