Search Results (3,815)

Financial time series forecasting remains a challenging task due to the high non-stationarity and concept drift inherent to market data. Existing deep learning models, such as LSTMs and transformers, typically employ static weights after training, limiting their ability to adapt to rapid market regime shifts (e.g., from trends to reversals). To bridge this gap between static parameters and dynamic environments, we propose a novel framework named Game-Theoretic HyperNetwork (GTH-Net), which introduces a context-aware meta-learning mechanism to achieve adaptive forecasting. Specifically, we first introduce an Evolutionary Game-Theoretic Correction Module (E-GTCM) to explicitly extract latent buying and selling pressure based on market microstructure priors through an iterative gated evolution process. Subsequently, we propose a HyperNetwork-based fusion mechanism that treats the extracted game state as a meta-context to dynamically generate the weights of the forecasting head. This allows the model to automatically switch its prediction rules in response to shifting market regimes. Extensive experiments on real-world stock datasets demonstrate that GTH-Net significantly outperforms baselines in terms of machine learning predictive accuracy and simulated financial profitability. Furthermore, ablation studies and parameter analysis confirm that the dynamic weight generation mechanism effectively captures market reversals caused by overcrowded trades. Full article

Ultra-high-strength steel sheets were joined by forge joining during hot stamping. This study investigated the influence of punch cross-sectional shape and punch tip inclination shape on joint strength through experiments and finite element simulation, with applications in hat bending. The experiments systematically evaluated various punch geometries by varying the punch’s cross-sectional shape and the aspect ratio of rectangular punches. A second set of experiments focused on the influence of punch tip inclination shape. These experiments examined a rectangular punch with a slope. Joint strength is primarily assessed by measuring the tensile shear load. Finite element simulation was used to analyze joining mechanisms, investigating contact pressure and surface expansion rate distribution. The results from the experiments consistently indicated that, for a constant cross-sectional area, punch shapes with a larger punch perimeter on the upper sheet yielded a higher tensile shear load, though the changing inclination shape of the rectangular punch tip did not lead to an observed improvement in joint strength. Finite element simulation analysis revealed that punch shapes promoting a uniform distribution of contact pressure and surface expansion rate across the joint area tended to exhibit higher joint strength compared with the same punch cross-sectional area but less uniform distribution, a tendency that was more pronounced for the distribution of contact pressure than for the surface expansion rate. Full article

Background: Global immunization programs continue to rely on needle-based injections despite persistent concerns regarding sharps disposal, accidental injuries, and the technical skill required for accurate intradermal administration. Needle-free jet injectors (NFJIs) are an alternative delivery method in which narrow, high-velocity liquid jets penetrate the skin without a needle. Contemporary designs, ranging from single-use disposable-syringe injectors to digitally controlled electromechanical devices, address historical safety issues and meet current WHO and FDA device expectations. Methods: Evidence from engineering analyses, preclinical modeling, and clinical trials was reviewed to characterize how jet velocity, nozzle structure, and formulation rheology influence skin penetration and drug dispersion. Published vaccine studies were examined for antibody responses, seroconversion, and reactogenicity compared with needle–syringe injection. Field vaccination campaign data from national campaigns and operational reports were evaluated to describe implementation steps, acceptability, and implementation constraints. Results: Published studies evaluating vaccines, including inactivated influenza, hepatitis B, typhoid, rabies, and measles, report antibody titers and seroconversion rates after NFJI administration that are comparable to those achieved with conventional intramuscular or intradermal needle injection. Needle-free delivery was associated with operational advantages in several immunization programs, including reduced sharps waste and improved vaccination rate during high-volume immunization campaigns. Local and systemic reactogenicity follows expected patterns, with slightly higher injection-site responses in some NFJI studies. Imaging and mechanical data confirm that jet performance depends on nozzle geometry and controlled pressure pulses. At the same time, formulation stability remains a critical determinant of successful jet-based vaccine administration, particularly for protein antigens, adjuvanted formulations, and emerging mRNA vaccines that may experience transient shear stress during high-velocity injection. Evidence from vaccination campaigns further indicates that needle-free jet injectors reduce sharps waste, simplify vaccine handling and administration procedures, and support rapid vaccine delivery in large-scale immunization programs. Conclusions: Needle-free jet injectors are a practical alternative to traditional needle-based injections for some vaccines. Their main benefits include enabling intradermal dose-sparing strategies, reducing reliance on sharps disposal methods, and enabling the efficient vaccination of large groups without compromising immunogenicity. Future research should define the physicochemical stability limits of biologic formulations subjected to jet injection and evaluate digitally controlled injectors capable of precise pressure modulation and adjustable delivery parameters. In addition, needle-free jet injection eliminates needle penetration and sharps handling, which may reduce needle-associated anxiety and improve vaccine acceptability among individuals with needle aversion. Full article

This study presents a comprehensive comparative analysis of the performance, combustion, and emission characteristics of a single-cylinder, four-stroke spark-ignition engine fueled by commercial gasoline and raw biogas enhanced with cerium oxide (CeO₂) nanoparticles. Raw biogas containing 58% methane was tested without carbon dioxide removal to reflect practical rural applications, while CeO₂ nanoparticles were ultrasonically dispersed in the fuel to promote homogeneous suspension and catalytic activity. Experiments were conducted under wide-open and part-throttle conditions across a range of engine speeds, with simultaneous measurement of brake thermal efficiency, brake-specific fuel consumption, volumetric efficiency, in-cylinder pressure, heat release rate, combustion phasing, and regulated emissions. The results showed that while gasoline consistently outperformed biogas in torque and power due to its higher heating value and flame speed, the addition of CeO₂ significantly reduced the performance gap. For the biogas mode, CeO₂ addition increased brake thermal efficiency by up to 5%, lowered brake-specific fuel consumption by up to 8%, and shifted the start of main combustion to earlier crank angles, indicating faster and more complete combustion, particularly at high loads where higher temperatures activate CeO₂’s catalytic behavior. Emission analysis revealed that CeO₂-blended biogas reduced carbon monoxide emissions by approximately 25% and unburned hydrocarbons by up to 55% compared with gasoline, while nitrogen oxide emissions were consistently 15–22% lower. These reductions were observed across both wide-open and part-throttle conditions, confirming improved combustion completeness and lower peak flame temperatures. These improvements are attributed to CeO₂’s oxygen-storage capability, catalytic oxidation activity, and enhanced thermal conductivity, which collectively strengthen combustion completeness and cyclic stability. The findings demonstrate that nanoparticle-enhanced biogas can substantially improve the environmental and operational viability of spark-ignition engines, offering a practical pathway for integrating renewable gaseous fuels into existing transportation systems. Full article

This study investigates the optimization of fabrication and operating parameters for poly(ether sulfone) (PES) ultrafiltration membranes embedded with Bismuth tungstate and multi-walled carbon nanotubes (MWCNTs) Bi₂WO₆/MWCNTs for the removal of dye pollutants from wastewater. Response surface methodology (RSM) coupled with Analysis of Variance (ANOVA) was employed to develop regression models for evaluating membrane performance in terms of dye rejection and permeate flux. A central composite design (CCD) was used to conduct a systematic series of ultrafiltration experiments. The effects of key variables, including Bi₂WO₆/MWCNTs loading (0–0.1 wt.%), operating pressure (5–9) bar, and methyl red (MR) dye concentration (50–150 ppm), on membrane separation performance were comprehensively examined. The developed models demonstrated strong statistical significance and accurately described the experimental data. Optimization results revealed that the operating parameters exerted a more pronounced influence on membrane performance than fabrication variables. The maximum MR rejection of 96.8457% was achieved at an optimal Bi₂WO₆/MWCNTs loading of 0.08 wt.%, dye concentration of 112.6 ppm, and operating pressure of 9 bar. Experimental validation confirmed the reliability and predictive capability of the proposed models. In order to provide high-performance membranes with enhanced permeability, antifouling resistance, and dye removal efficiency for useful wastewater treatment applications, this study attempts to optimize the operating and preparation parameters for adding Bi₂WO₆/MWCNT nanocomposites into PES membranes. Full article

Accurate absolute pressure measurement is of great importance in industrial control, environmental monitoring, and aerospace. Traditional fiber-optic Fabry–Perot (F-P) pressure sensors usually involve complex microfabrication and high-cost demodulation systems, while conventional diaphragm capsule sensors are limited in sensitivity and resolution. This work presents a low-cost, high-resolution fiber-optic F-P absolute pressure sensor. The sensor uses a vacuum capsule as one reflective surface and a partially reflective fiber collimator as the other, forming a low-finesse F-P interferometer. The cavity length is linearly modulated by the elastic deformation of the capsule under pressure, and high-precision demodulation is realized using frequency modulated continuous wave (FMCW) interferometry instead of conventional spectral methods. Static experiments from 10 to 110 kPa show that the sensor exhibits a high sensitivity of 15,105 nm/kPa and a resolution of 3.3 Pa. Furthermore, the sensor operates normally within the range of −20 °C to 70 °C, exhibiting a pressure–temperature cross-sensitivity of 0.081 kPa/°C and a cavity length drift of 496 nm/h. With the advantages of high performance, simple structure, low cost, and good scalability by selecting different capsules, the proposed sensor has promising potential for practical applications in pressure measurement fields. Full article

The modern high-pressure lifestyle has led to an increasing emphasis on the healing construction of residential spaces, while air, as an important environmental factor, has received little attention in terms of situational healing experiences within the context of residential culture. Employing grounded theory, this study develops a theoretical model to explain the mechanism through which indoor air environments influence the healing benefits of residential spaces. Guided by the dynamic interaction process of “physical attributes–embodied cognition–behavioral regulation–social context”, the analysis focuses on human embodied perception and emotional responses to indoor air environments as the foundation for healing effects. It highlights the joint role of behavioral regulation and social context, ultimately affecting four levels of healing benefits. Furthermore, it systematically elaborates a theoretical model for embodied interactive residential air experiences, expanding healing environment theory from a contextual air experience perspective, and providing new research paradigm and insights for promoting healing benefits in residential settings. Full article

To investigate the deterioration law of the mechanical properties of PVA-fiber-reinforced rubber concrete under the combined action of high-temperature and salt erosion, physical index tests, dynamic mechanical property experiments, and microstructural morphology observations were carried out on specimens subjected to different temperatures (ambient temperature, 100 °C, 300 °C) and various solution attacks (water, 5% NaCl, 5% Na₂SO₄, and 5% NaCl + 5% Na₂SO₄ mixture). The results show that, after exposure to 300 °C, the PVA fibers melt and the rubber pyrolyzes, since this temperature exceeds their melting points. A residual pore network is formed inside the matrix, and the damage degree of ultrasonic pulse velocity is about 2.3 times that of the 100 °C group. Although salt solution and its crystallization products can physically fill the pores and cause a partial recovery of pulse velocity, this change is mainly due to the alteration of the pore medium and does not represent a substantial restoration of the microstructure. The effects of different salt solutions on dynamic mechanical properties vary significantly: Sulfate erosion improves the dynamic performance significantly at ambient temperature by forming gypsum and ettringite to fill pores, but this strengthening effect disappears after 300 °C. Sodium chloride attack generates Friedel’s salt and consumes C₃A, leading to general strength deterioration. In composite salt erosion, the competitive and synergistic effects of Cl⁻ and SO₄²⁻ destabilize erosion products and weaken interfacial bonding, resulting in consistent decreases in dynamic compressive strength and elastic modulus under all temperatures and impact pressures. The strength reduction reaches 66.2% after 300 °C. Microscopic analysis confirms that composite salt erosion leads to the dissolution of ettringite and loose structure, which verifies the synergistic deterioration law of macroscopic properties. This study systematically reveals the damage evolution mechanism of PVA-fiber-reinforced rubber concrete under the coupled action of high-temperature and salt erosion, and provides a theoretical basis for the dynamic bearing capacity evaluation and durability design of concrete structures in such coupled environments. Full article

A high-speed magnetic pump rated at 7800 r/min was studied. A numerical model was established, and a hydraulic, vibration, and noise testing system was set up to conduct flow simulations, noise, and vibration experiments at different speeds. The results show that increasing speed leads to a higher pressure difference between the pump chamber and the cooling circuit. Meanwhile, the turbulent kinetic energy at the impeller outlet increases. Despite an increase in energy loss, the loss ratio decreases, and overall efficiency improves. The internal flow noise collected by the outlet hydrophone mainly comes from Rotor–Stator Interference (RSI), and it can sensitively capture changes in rotational speed. The dominant frequency of the outlet noise agrees well with the blade frequency calculated from the set speed, with a maximum deviation of 0.26%. As the speed increases, the overall sound pressure level (OASPL) at the inlet and outlet and the Root Mean Square (RMS) acceleration values at the outlet and pump body generally increase, while the acceleration at the motor base shows a decreasing trend. The conclusions are helpful for the design and optimization of rotary machinery such as high-speed magnetic pumps. Full article

As high rates of sexual violence worldwide have increasingly been met with educational initiatives promoting sexual consent as a core preventive strategy, it becomes crucial to understand how consent is actually conceptualized in specific sociocultural contexts. This study examines how a group of adult women in Chile conceptualize sexual consent and how their understandings align with, expand or diverge from the definition promoted by the World Association for Sexual Health (WAS), a widely adopted international framework. Using a therapeutic writing methodology designed to support emotional safety and reflective depth, 34 women completed a collective writing workshop. For this paper, the main writing exercise was analyzed through thematic analysis. Results show three overarching themes: sexual consent as a self-directed and desire-aligned experience; the intricacies of giving in to sexual encounters as shaped by social expectations, emotional pressures, and relational considerations; and the tensions when differentiating consent from giving in, a distinction experienced as meaningful yet fluid and learned over time. Together, these findings reveal that our participants’ conceptualizations of sexual consent extend beyond normative international models, highlighting the need for attuned consent frameworks and educational approaches designed to prevent sexual violence. Full article

To address the issues of high impurity rates and grain loss during the wheat cleaning process, a coupled Computational Fluid Dynamics (CFD) and Discrete Element Method (DEM) approach was employed to investigate the internal airflow field and the fluid–solid coupling process of the wheat cleaning device. The numerical simulation of the three-dimensional internal flow field is carried out in the high-Reynolds-number turbulent region, and the transient double precision solver based on the pressure–velocity coupling algorithm is used. The effects of the air inlet velocity and angle on the airflow field distribution and air separation efficiency were analyzed through CFD simulation. Based on this, the structure of the cleaning device was optimized, and the movement characteristics of materials under various wind forces were compared through CFD-DEM coupling simulation. The results showed that the optimal air separation parameters were an air inlet velocity of 10 m/s and an air inlet angle of 20 degrees. Under these conditions, the airflow distribution in the air separation box was uniform, and the impurity separation efficiency reached the highest level. After optimizing the equipment by installing a high-pressure fan, the number of impurities in the wheat collection box under windy conditions was 265, a reduction of 53.8% compared to 573 under windless conditions. Finally, through repeated experiments on the entire machine, it was verified that the impurity rate of the optimized device was 1.722% and the loss rate was 0.622%, which were 0.23% and 0.12% lower than those of the existing equipment, respectively, consistent with the simulation results. This study provides theoretical basis and technical support for the optimization design of wheat cleaning equipment. Full article

Compared to traditional offline collaboration, current online collaboration often lacks nonverbal social cues, resulting in lower efficiency and a reduced emotional connection between teammates. To address this issue, this study used a two-player collaborative puzzle game as the experimental setting to explore the impact of two nonverbal social cues, emotion and gaze, on collaborative experience and performance. Specifically, this study designed four collaborative modes: with and without teammates’ facial expressions, and with and without teammates’ gaze points. Sixty-two participants took part in the experiment, and each pair was required to complete these four patterns. Subsequently, we analyzed their collaborative experience through subjective questionnaires, objective facial expressions, and gaze overlap rates. The experimental results revealed that teammates’ gaze could effectively enhance collaborative efficiency, while facial expression is key to optimizing subjective experience. Combining both cues further acquires advantages in cognitive and emotional dimensions, leading to improved performance outcomes. The study also indicated that facial expressions could alleviate the social pressure triggered by shared gaze from teammates. Additionally, the study also examined how personality differences influenced collaborative experiences and performance. The results indicated that individuals with high agreeableness actively seek social cues, leading to more positive collaborative experiences. This study provides empirical evidence for understanding the interactive mechanisms of cognitive and emotional processes during online collaboration, and points the way toward designing adaptive, personalized intelligent collaborative systems. Full article

Volatile organic compounds (VOCs, dominated by xylene, toluene, and benzene) and paint mist emissions from ship painting represent a major environmental and health concern, posing a critical bottleneck to the green transformation of the shipbuilding industry. To tackle this challenge, this study presents an integrated recovery system designed specifically for ship automatic-spraying robots. Guided by the synergistic principle of “air-curtain containment, multi-stage adsorption, and negative-pressure recovery,” the system features a modular design that ensures full compatibility with the robots’ spraying trajectory without operational interference. Core adsorption materials, namely glass fiber filter cotton and honeycomb activated carbon fiber, were selected to suit the high-humidity and high-pollutant-concentration environment typical of ship painting. An appropriately matched axial flow fan maintains stable negative pressure throughout the system. Furthermore, the design integrates an air curtain isolation subsystem and an automated control subsystem, enabling coordinated operation and real-time adjustment. Using ANSYS Fluent, geometric and flow field simulation models were established to analyze airflow distribution and pollutant adsorption behavior, which led to the optimization of key structural and material parameters. Field experiments conducted in shipyard environments demonstrated the system’s superior performance: it achieved a VOC removal efficiency of 88.4% and a paint mist capture efficiency of 85.7% under optimal working conditions, with a maximum simulated paint mist capture efficiency of 86.2%. The system maintained stable performance under complex vertical and overhead spraying conditions, with an efficiency attenuation of less than 1.5%, and its outlet emissions fully complied with the mandatory limits specified in the Emission Standard of Air Pollutants for the Shipbuilding Industry (GB 30981.2-2025). The relative error between experimental data and simulation results is less than 2%, confirming the reliability and practicality of the proposed system. This research provides an efficient and adaptable pollution control solution for green shipbuilding and offers valuable technical insights for the sustainable upgrading of automated painting processes in heavy industries. Full article

Metal hydrides store hydrogen in the solid state with high density and inherent safety, and their thermodynamic characteristics are typically described by the pressure–composition–isotherm (PCI) curve. In the plateau pressure region of the PCI curve, the equilibrium pressure remains nearly constant over a wide hydrogen concentration range, making conventional pressure-based methods unsuitable for quantifying the hydrogen amount in metal hydride vessels. This study proposes a strain-based method to quantify the hydrogen amount in a metal hydride vessel by measuring the strain induced on the metal hydride vessel surface due to the volumetric change of the metal hydride during hydrogen adsorption and desorption. The installation of strain gauges on the metal hydride vessel was verified using argon pressurization tests. The metal hydride was activated prior to controlled hydrogen desorption experiments aimed at quantifying the amount of hydrogen remaining in the vessel. A correlation between strain and hydrogen amount was obtained from experiments conducted at discrete measurement points. The hydrogen amount estimated using the strain-based method was further evaluated through continuous time-series desorption tests and showed good agreement with the results obtained from the mass flow controller (MFC)-based method, with a maximum difference of 4.5%. These results demonstrate that the proposed method provides a simple and reliable approach for quantifying the hydrogen amount in metal hydride vessels. Full article

Additive-manufactured (AM) 316L stainless steel, produced via direct metal laser sintering (DMLS) and characterised by a surface topography of high irregularities and tensile residual stresses with specific anisotropy, was subjected to milling and shot peening. The milling process caused a reduction in surface topography parameters, but tensile residual stresses increased significantly. The shot peening process was carried out according to the full factorial design 3² and technological parameters such as a shot diameter in the range of 1-3 mm and an air supply pressure between 0.2 and 0.6 MPa. As a result of the experiments and the analysis, reduced surface topography was achieved, and a favourable residual stress state was formed with compressive stresses. The mechanism of the changes was demonstrated via microstructure observation and statistical models obtained by mathematical analysis. Full article