Search Results (4,017)

To construct Caputo fractional-order time-delayed cellar neural networks (FOTDCNNs) that characterize real environments, this article introduces partial uncertainties, fuzzy operators, and nonlinear activation functions into the network models. Specifically, both the fuzzy AND operator and the fuzzy OR operator are contemplated in the master–slave systems. In response to the properties of the considered cellar neural networks (NNs), this article designs a new class of mixed control protocols that utilize both the error feedback information of systems and the sampling information of impulse moments to achieve network synchronization tasks. This approach overcomes the interference of time delays and uncertainties on network stability. By integrating the fractional-order comparison principle, fractional-order stability theory, and hybrid control schemes, readily verifiable asymptotic synchronization conditions for the studied fuzzy cellar NNs are established, and the range of system parameters is determined. Unlike previous results, the impulse gain spectrum considered in this study is no longer confined to a local interval $(-2,0)$ and can be extended to almost the entire real number domain. This spectrum extension relaxes the synchronization conditions, ensuring a broader applicability of the proposed control schemes. Full article

This study aimed to assess the efficacy of a single intra-articular injection of autologous stromal vascular fraction (SVF) in dogs with chronic lameness due to advanced elbow osteoarthritis (OA) that were unresponsive to conventional drug therapy. In this clinical, prospective, non-blinded, single-center study, twenty-three dogs received autologous SVF derived from falciform adipose tissue. Primary outcome measures over the six-month study period included clinical-orthopedic and radiographic examinations, objective gait analysis and validated owner questionnaires. In 19 of 23 joints, no progression of OA was visible radiographically. Peak vertical force improved significantly at three months and vertical impulse at six months after the injection compared to baseline. Over 33% of dogs demonstrated treatment-related improvements in lameness based on objective gait analysis. Owner questionnaires indicated significant improvement in clinical signs throughout the study period and 26% of dogs showed treatment-related improvements in pain scores according to the Canine Brief Pain Inventory. No side effects were reported. These findings suggest that autologous regenerative cell therapy may provide a promising treatment option for dogs with advanced OA that do not respond to conventional drug therapy. However, the treatment did not improve the clinical symptoms in all dogs, so it cannot be recommended for all patients. Full article

Considering the dataset of information related to Chinese coal-fired thermal power plants during the 2005–2017 period, we initially investigated the orthogonalized response of the carbon emission to energy consumption and power generation by using Bayesian vector autoregressions and feedback solutions for impulse control technology. The results showed that the effects of energy consumption and power generation on carbon emissions were significant. The Chinese government has launched a program aimed at curbing carbon emission peaks and neutralizing or decreasing carbon emissions. The causal relationship concludes that China still needs further investment in emission abatement, improvement related to the level of openness to the outside world, and the strengthening of the construction of green zones for industrial transfer to mitigate carbon emissions. Full article

Background: The previous literature has revealed the relationship between alcohol abuse and violent behaviours; however, the results are not always conclusive, highlighting the need to explore other variables that allow us to establish risk profiles. Aim: The goal is to examine whether the relation between alcohol abuse and physical violence towards a partner can be influenced (moderate) by difficulties in emotional regulation. Setting: A public high school in Manabí (Ecuador). Participants: A total of 1519 high school students with ages between 14 and 18 years (mean = 15.77, SD = 1.22), with 54% (n = 820) being male. Main Outcome Measures: The measures we observed were alcohol abuse (i.e., frequency of alcohol abuse in the past 30 days), physical violence exercised towards a partner (Violence Received, Exercised and Perceived in Dating Relationships of Young People and Adolescents) and emotional dysregulation (Difficulties in Emotional Regulation Scale; DERS). Results: It is observed that there exists significantly higher alcohol abuse in males, regardless of their age, as well as more physical violence by adolescent males towards their partners. Direct effects of alcohol abuse on physical intimate partner violence are observed in males from the age of 16 and in females from the age of 14. Moreover, the direct effects of different emotional dysregulation strategies on physical violence depend on gender. Conclusion: The moderating effects of emotional dysregulation strategies between alcohol abuse and physical intimate partner violence are observed only in the case of adolescent females (16–17 years). In particular, emotional dysregulation variables such as non-awareness, impulse, nonacceptance, or lack of strategies interfere as moderators in the relationship between excessive alcohol abuse and physical violence towards a partner. In the case of non-awareness, contrary to the other three, when scores are low or moderate, a statistically significant relationship between alcohol abuse and violence is observed. Full article

Dynamic compaction (DC) represents a cost-effective method for reinforcing subgrade and is particularly suited to treating large-scale building subgrade. Nevertheless, the effect of DC reinforcement on high groundwater level (HGL) subgrade remains uncertain due to the lack of clarity surrounding the energy transfer mechanism of DC in HGL subgrade. In this paper, an outdoor model test of HGL subgrade was conducted based on the DC method. The temporal evolution of the internal transverse and vertical dynamic stresses in soil under different water levels, energy levels, and tamper weight conditions was monitored, and the DC mechanism of HGL subgrade was described from the perspectives of the dynamic stress waveform, peak development, and attenuation. On this basis, a novel methodology for assessing the extent of subgrade reinforcement through the utilization of impulses was put forth, thereby facilitating a more precise evaluation. The results showed that the HGL is obstructive in DC energy transfer. The peak dynamic stress, depth of impact and maximum impulse per unit area were markedly diminished when tamping the water surface. The study results also recommend that construction could expand the application range of the DC method and provide engineering suggestions for the selection of construction parameters and subsequent building construction. Full article

In this paper, we study the asymptotical stability of the exact solutions of nonlinear impulsive differential equations with the Lipschitz continuous function $f(t,x)$ for the dynamic system and for the impulsive term Lipschitz continuous delayed functions $I_k$. In order to obtain numerical methods with a high order of convergence and that are capable of preserving the asymptotical stability of the exact solutions of these equations, impulsive discrete Runge–Kutta methods and impulsive continuous Runge–Kutta methods are constructed, respectively. For these different types of numerical methods, different convergence results are obtained and the sufficient conditions for asymptotical stability of these numerical methods are also obtained, respectively. Finally, some numerical examples are provided to confirm the theoretical results. Full article

In ecological modeling, symmetry can manifest in multiple ways, significantly contributing to our understanding of ecosystem stability, species interactions, and ecological balance. Considering the bloom phenomenon caused by excessive algae in ponds and its impact on aquaculture, we establish a class of algae–fish ecological models with two state-dependent impulse controls. In this paper, we first discuss the existence of positive equilibria in the system without impulses. Second, the existence and asymptotic stability of the order-1 and order-2 periodic solutions are analyzed by applying successor functions and a Similar Poincare Criterion. Finally, numerical simulations demonstrate that the model exhibits order-1 and order-2 periodic solutions, clarifying that the system with two impulses can address the problem more effectively. Full article

Mental distress-induced imbalances in autonomic nervous system activities adversely affect the electrical stability of the cardiac system, with heart rate variability (HRV) identified as a related indicator. Traditional HRV measurements use electrocardiography (ECG), but impulse radio ultra-wideband (IR-UWB) radar has shown potential in HRV measurement, although it is rarely applied to psychological studies. This study aimed to assess early high levels of mental distress using HRV indices obtained using radar through modified signal processing tailored to reduce phase noise and improve positional accuracy. We conducted 120 evaluations on 15 office workers from a software startup, with each 5 min evaluation using both radar and ECG. Visual analog scale (VAS) scores were collected to assess mental distress, with evaluations scoring 7.5 or higher classified as high-mental distress group, while the remainder formed the control group. Evaluations indicating high levels of mental distress showed significantly lower HRV compared to the control group, with radar-derived indices correlating strongly with ECG results. The radar-based analysis demonstrated a significant ability to differentiate high mental distress, supported by receiver operating characteristic (ROC) analysis. These findings suggest that IR-UWB radar could be a supportive tool for distinguishing high levels of mental stress, offering clinicians complementary diagnostic insights. Full article

In a world facing significant planetary health challenges, the power of prospection—our capacity to envision and shape future possibilities—gains importance. Recently, three conceptualisations have been introduced to measure individuals’ inclination and ability to imagine desirable societal alternatives: utopian, transformative utopian impulse for planetary health, and environmental cognitive alternatives. We propose that these constructs, founded on different theoretical bases, each offer unique perspectives on a common process: the mental simulation of societies that positively deviate from the status quo, which we refer to as collective positive prospection. Data from a correlational survey (N = 485) show that these dimensions, while distinct, are highly interrelated, supporting their potential complementarity for understanding individual differences in collective positive prospection. Results also emphasise the importance of integrating these diverse dimensions to enhance the prediction of intentions, particularly pro-environmental intentions. Furthermore, our results suggest that the precision of prospection content, alongside its compatibility with behaviours, enhances predictive accuracy. Although preliminary, these findings provide valuable insights on both theoretical and practical levels, highlighting the importance of integrating diverse conceptualizations to better understand the functioning of collective positive prospection and suggesting that an integrative scale could be beneficial for future research in this area. Full article

Steel structures are vulnerable to fire due to the degradation of their mechanical properties at high temperatures, making it necessary to protect them when exposed to high temperatures. This paper presents the results of an experimental research work to characterise the mechanical properties of gypsum-based fire-resistant mortars with and without nano and micro silica particles by destructive and non-destructive tests at ambient temperature. Five compositions were studied: one commercial composition was used as a reference and four were developed in the laboratory. Two were based on gypsum with perlite or vermiculite, and the other two included nano and micro silica particles. Twenty specimens underwent ultrasonic pulse velocity, flexural, and compression tests, while five specimens were tested by the impulse excitation of vibration. Young’s modulus, shear modulus, and Poisson’s ratio were assessed by non-destructive tests, and the flexural and compression strengths were assessed by destructive tests. Additional tests included density and porosity assessments, thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy. Results indicated that adding nano and micro silica particles posed challenges to the mechanical and physical properties. Despite this, vermiculite compositions showcased superior or similar properties to the commercial composition, while perlite compositions exhibited slightly lower properties. Full article

An infinite impulse response (IIR) system might comprise a multimodal error surface and accurately discovering the appropriate filter parameters for system modeling remains complicated. The swarm intelligence algorithms facilitate the IIR filter’s parameters by exploring parameter domains and exploiting acceptable filter sets. This paper presents an enhanced symmetric sand cat swarm optimization with multiple strategies (MSSCSO) to achieve adaptive IIR system identification. The principal objective is to recognize the most appropriate regulating coefficients and to minimize the mean square error (MSE) between an unidentified system’s input and the IIR filter’s output. The MSSCSO with symmetric cooperative swarms integrates the ranking-based mutation operator, elite opposition-based learning strategy, and simplex method to capture supplementary advantages, disrupt regional extreme solutions, and identify the finest potential solutions. The MSSCSO not only receives extensive exploration and exploitation to refrain from precocious convergence and foster computational efficiency; it also endures robustness and reliability to facilitate demographic variability and elevate estimation precision. The experimental results manifest that the practicality and feasibility of the MSSCSO are superior to those of other methods in terms of convergence speed, calculation precision, detection efficiency, regulating coefficients, and MSE fitness value. Full article

Background: Understanding the diverse acute effects elicited by physiotherapists in soccer players may be pertinent for enhancing performance and aiding in the mitigation of injury risk. Methods: Fifty regional-level soccer players aged 13 to 15 took part in a randomized double-blind trial. They were allocated randomly to either receive diagonal manual mobilization (DM) treatment or undergo a Nordic hamstring curl (NHC) intervention, designated as the control group. Evaluations were carried out before and after the interventions to gauge standing knee extensors (KE) and knee flexors (KF) strength using the ForceFrame Strength Testing System. The recorded variables encompassed average, maximal force, and maximal impulse for both KE and KF. Results: Following the intervention, evaluations showed no significant differences between groups in KF maximal force (F_1,48 = 1.238; p = 0.271; ${\eta }_p^2$ = 0.025), KF average force (F_1,48 = 0.957; p = 0.333; ${\eta }_p^2$ = 0.020), KF maximal impulse (F_1,48 = 0.246; p = 0.622; ${\eta }_p^2$ = 0.005), KE maximal force (F_1,48 = 1.514; p = 0.225; ${\eta }_p^2$ = 0.031), KE average force (F_1,48 = 0.118; p = 0.733; ${\eta }_p^2$ = 0.002), and KE maximal impulse (F_1,48 = 2.540; p = 0.118; ${\eta }_p^2$ = 0.050). Analysis within the DM group showed significant differences in KF maximal force (24.2 N; p = 0.004), KF average force (23.4 N; p = 0.001), KE maximal force (25.8 N; p = 0.005), KE average force (20.0 N; p = 0.044), and KE maximal impulse (265.9 Ns; p = 0.027), although no significant differences were found in KF maximal impulse (150.1 Ns; p = 0.058). Conclusions: This study indicates that both DM and NHC elicit similar effects on acute responses in KE and KF strength following intervention, although DM shows more favorable adaptations within the group. Perhaps DM could serve as a suitable warm-up strategy in specific circumstances, immediately influencing readiness for strength activities. Full article

The search for a synthesis method to create longer ZnO NWAs with high-quality vertical alignment, and the investigation of their electrical properties, have become increasingly important. In this study, a hydrothermal method for growing vertically aligned arrays of ZnO nanowires (NWs) using localized heating was utilized. To produce longer NWs, the temperature environment of the growth system was optimized with a novel reaction container that provided improved thermal insulation. At a process temperature above ~90 °C, ZnO NWs reached a length of ~26.8 µm within 24 h, corresponding to a growth rate of 1.1 µm/h, nearly double the rate of 0.6 µm/h observed in traditional chemical bath growth using a glass reactor. The densely grown NWs (~1.9/µm²), with a diameter of ~0.65 µm, exhibited a preferred hexagonal c-axis orientation and were vertically aligned to the (100) silicon (Si) substrate. These NW structures have multiple applications, e.g., in piezotronic strain sensors, gas sensing, and piezoelectric energy harvesting. As proof of concept, a piezoelectric nanogenerator (PENG) was fabricated by embedding the NWs in an S1818 polymer matrix over a 15 mm × 15 mm area. Under repeated impulse-type compressive forces of 0.9 N, a maximum peak output voltage of ~95.9 mV was recorded, which is higher by a factor of four to five than the peak output voltage of 21.6 mV previously obtained with NWs measuring ~1.8 µm in length. Full article

Numerical simulations were conducted to investigate the wave features of subaerial granular landslide-generated impulse waves and their impact on slopes. A numerical solution was obtained by coupling smoothed particle hydrodynamics (SPH) and the discrete element method (DEM). Several predictive equations were tested for their applicability in predicting the maximum crest amplitude of impulse waves generated by slides of different shapes. The results indicated that the predictive model developed by Heller and Hager, utilising slide centroid impact velocity, showed favourable prediction accuracy for the maximum crest amplitude, almost independent of the slide shape at impact. Regarding the leading wave, although the wave profile and velocity distribution deviated significantly from a solitary wave of the same wave amplitude, the maximum run-up could be satisfactorily estimated using solitary wave theory. In addition, the increase in the maximum dynamic forces exerted by the impulse waves on the slope followed a power law with the incident wave amplitude. Full article

In this paper, the advantages of the joint use of MHz- and GHz-frequency band impulses when employing contactless ground penetration radar (GPR) for the remote sensing of biomass, the height of the wheat canopy, and underlying soil moisture were experimentally investigated. A MHz-frequency band nanosecond impulse with a duration of 1.2 ns (average frequency of 750 MHz and spectrum bandwidth of 580 MHz, at a level of –6 dB) was emitted and received by a GPR OKO-3 equipped with an AB-900 M3 antenna unit. A GHz-frequency band sub-nanosecond impulse with a duration of 0.5 ns (average frequency of 3.2 GHz and spectral bandwidth of 1.36 GHz, at a level of −6 dB) was generated using a horn antenna and a Keysight FieldFox N9917B 18 GHz vector network analyzer. It has been shown that changes in the relative amplitudes and time delays of nanosecond impulses, reflected from a soil surface covered with wheat at a height from 0 to 87 cm and fresh above-ground biomass (AGB) from 0 to 1.5 kg/m², do not exceed 6% and 0.09 ns, respectively. GPR nanosecond impulses reflected/scattered by the wheat canopy have not been detected. In this research, sub-nanosecond impulses reflected/scattered by the wheat canopy have been confidently identified and make it possible to measure the wheat height (fresh AGB up to 2.3 kg/m² and height up to 104 cm) with a determination coefficient (R²) of ~0.99 and a bias of ~−7 cm, as well as fresh AGB where R² = 0.97, with a bias = −0.09 kg/m², and a root-mean-square error of 0.1 kg/m². The joint use of impulses in two different MHz- and GHz-frequency bands will, in the future, make it possible to create UAV-based reflectometers for simultaneously mapping the soil moisture, height, and biomass of vegetation for precision farming systems. Full article