Nanoparticles composed of high-entropy alloys (HEA NPs) exhibit remarkable performance in electrocatalytic processes such as hydrogen evolution and oxidations. In this study, two types quinary HEA NPs PtRhPdIrRu, are synthesized, featuring disordered crystallized nanostructures, both with without a boiling mixture. The (d-HEA size 3.5 nm is synthesized under intense conditions, attributed to improved heat mass transfer during reduction precursors particle growth. displayed an exceptionally...

Abstract To investigate the prevalence, types, and risk factors of functional gastrointestinal diseases (FGIDs) in Hainan Province, China, order to provide insights for future prevention treatment strategies. A questionnaire survey was conducted from July 2022 May 2023, using stratified sampling sample local residents five cities (20 townships) Province. Out 2057 surveyed, 659 individuals (32.0%) reported experiencing at least one FGID. The most prevalent FGIDs were dyspepsia (FD) (10.7%),...

A power electronic converter is a switching system; the key to modeling it how describe interaction between discrete switch variables and continuous state in unified model. method based on sigmoid functions proposed. Since function continuous, smooth, differentiable, saturated at certain value, with large steepness factor used approximate process of switch; transformed from system so that nonlinear analysis design methods can be directly applied control system. Sigmoid equivalent circuit...

The memristor is referred to as the fourth fundamental passive circuit element of which inherent nonlinear properties offer construct chaos circuits. In this paper, a flux-controlled developed, and then van der Pol oscillator implemented based on new circuit. stability circuit, occurring conditions Hopf bifurcation limit circle self-excited oscillation are analyzed; meanwhile, under condition with an external exciting source, exhibits complicated dynamic behavior, occurs within certain...

By extracting and simplifying the characteristics of commercial streets with arcades (Qilou) in Nanning, tissue map Qilou which reflects urban morphology, including road network form, block scale, building scale other a hot humid area is obtained. In addition, sunshine simulation performed by using design software an environment comprising to simulate street sunlight environments under various conditions. The relationship among height-to-width ratio, hours, orientation angle achieved...

Considering the characteristics of a campus environment and rules that govern outdoor sound propagation, this paper identifies traffic noise as dominant source based on measurement environment. A propagation model is suitable for university campuses was developed used it to create map ambient area teaching building Guangxi University. This then utilized analyze The results revealed given building, disturbance high-rise classrooms more significant compared impact low-rise classrooms....

Summary To achieve the satisfactory control performance of a dynamic system using proportion‐integration‐differentiation (PID) controller, it is necessary that three parameters PID controller are set to values suit be controlled. Most current applications employ fixed setting not adequate for nonlinear time varying systems with uncertainty and disturbances. In this paper, we use neuron weighted tuning functions develop self‐tuning methods can automatically tune controllers. The weighting...

With respect to the light environment of exhibition halls for Chinese calligraphy and painting works in museums, daylighting design these display spaces have been studied, key factors, such as pattern, arrangement exhibits are examined explored by field trips. Then, divided into diverse categories whose sky environments predicted demands exhibits. Under changed situations, daylight parameters, i.e., factor (DF) DF uniformity, discomfort glare index (DGI) luminance distribution calculated....

For the purpose of reducing impact noise transmission across floating floors in residential buildings, two main sound paths floor structure are considered: stud path and cavity path.The each is analysed separately: through predicted by statistical energy analysis (SEA).Then, insulation prediction model established.There reasonable agreement between theoretical measurement, results show that a resilient layer with low stiffness can attenuate bridge effect, resulting higher insulation.Then,...

The characteristics of a power electronic circuit composed rectifier bridge and passive filter correspond with the basic extended memristors. Using PI control system an <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LLC</i> resonant dc–dc converter as example, this article establishes equivalent memristor model for investigates its dynamics. Floquet theory, bifurcation diagram, Poincaré map are used to investigate dynamics system....

An approach to the modeling and regulation problem of a buck converter which relies on its hybrid nature is presented. The modeled as switched affine system. Then, using stored energy in inductor capacitor common Lyapunov function, switching rules activation region all subsystems are defined assess quadratic stability converter. Simulation results provided compared with those PID control demonstrate validity this approach. proposed methodology can be extended other types port controlled...

By analyzing measurements of the thermal environment a qilou (arcade building) street, this study used relative warmth index (RWI) to evaluate comfort in colonnade space qilou. The analysis influence temperature, humidity, and wind speed on street was conducted, it shown that ambient had strong RWI, indicating proper increase positively affected space. Then, also analyzed effects different forms streets by employing computational fluid dynamics (CFD) summarized architectural design measures...

In this study, based on the current daylighting situation of a museum sculpture exhibition hall, space is classified according to requirements sculptures. Additionally, pattern for hall and display layout exhibits are summarized. The parameters under different scenarios calculated. simulated analyzed three conditions (flat skylights, flat skylights with side windows, high windows), optimized patterns components. It discovered that combination daylight factor (DF) uniformity (UD) as well...

Two new pulse width modulation (PWM) schemes: chaos-based sinusoidal PWM (SPWM) and space vector (SVPWM) are brought forward. There cluster harmonics around the multiples of switching frequency in conventional SPWM SVPWM output waves owing to their fixed frequencies. Chaos-based strategies utilize a chaotic changing spread continuously wideband area so that peak can be reduced greatly. This an effective way suppress harmonic reduce ripple current torque induction motor drives. The good...

In hot summers, air conditioning (AC) and mechanical ventilation (such as fans) are used cooling modes that strongly influence the resultant indoor environment, like thermal comfort quality in shops of a Nanning arcade street (qilou). The circulation mode greatly affects environment level freshness. approaches for effectively improving developed qilou with air-conditioner humid region southern China. Consequently, purpose this study is to assess different schemes order identify best one. By...

Many DC/DC converters with voltage boosting functions have zeros on the right half of complex plane; they are non-minimum phase systems. Conventional linear controllers trouble obtaining ideal control quality simultaneously satisfying performance requirements respect to stability, speed, accuracy, robustness, and simplicity. This paper combines a proportional integral (PI) rule an adaptive parameter-adjusting circuit composed memristors adaptively adjusts controller parameters through...

Because of the manufacturing variations circuit elements and effects parasitic parameters, switching parallel-connected modules cannot be synchronously switched. Consequently, characteristics these converters, which are multi-mode, high-order systems, comprehensively described using reduced-order models based on symmetry topology parameters. It is also difficult to fully describe systems discrete mapping averaged models. Therefore, we developed a smooth, sigmoid function-based...

Daylighting in educational buildings is a key factor ensuring visual comfort and maintaining indoor environmental quality. In this context, daylight quality plays crucial role enhancing the lighting conditions within classrooms. Due to local climate, classrooms with double-side windows are widely prevalent southern China; however, these wide can sometimes lead uncomfortable glare uneven distribution. response, address improve quality, study selected some at Guangxi University as typical case...

Existing large-signal control schemes for DC/DC converters formulate strategies based primarily on nonlinear theory, and the associated design implementation are relatively complex. In this work, a decomposition modeling inverse-system decoupling method is proposed that operate under disturbances. First, circuit-averaged model established. The system has double closed-loop structure composed of voltage loop current loop. Then, voltage-loop current-loop controlled subsystems decoupled...

High-entropy-alloy nanoparticles (HEA NPs) show extraordinary performances for electrocatalytic hydrogen evolution and oxidations. Herein, two types of PtRhPdIrRu quinary HEA NPs with disordered crystallized nanostructures were synthesized without the mixture boiling. Under vigorous boiling, structure in size 3.5 nm due to enhanced heat transfer mass transfer. The (d-HEA) exhibited ultrahigh turnover frequency 33.1 s–1 at overpotential 50 mV, which was 5.4 times higher than commercial Pt...

A flux-controlled cubic memristor circuit is developed and a van der Pol oscillator implemented based on the inherent non-linear properties of this memristor. Meanwhile linear feedback controller designed to synchronization two chaotic circuit. The range gain for synchronizing derived. Both results simulations experiments validate proposed oscillation chaos method.

As long as multi-element partition with windows and doors widely exists in variety kind of buildings, the overall insulation is determined mainly by sound transmission through weaker members such doors. The selection to thought be a key. Under condition that composite wall area each member are known, an approach based on Artificial Immune Algorithm proposed determine weighted insulations (wall, window door) inverse prediction which was developed this paper.

This paper describes a theoretical method for predicting the improvement of impact sound insulation to floating floor with resilient interlayer. Statistical energy analysis (SEA) model, which is skilful in calculating sound, set up reduction pressure level downstairs room. The transmission paths include direct path and flanking are analyzed find dominant one; factors that affect explored. Then, room determined comparisons between predicted measured data conducted. It indicated across floor,...