Temperature-Based Fan Speed Optimization Strategy

As energy efficiency and indoor comfort increasingly become key standards in modern residential and office environments,research on intelligent fan speed control systems has become particularly important.This study aims to develop a temperature-feedback-based fan speed optimization strategy to achieve higher energy efficiency and user comfort.Firstly,by analyzing existing fan speed control technologies,their main limitations are identified,such as the inability to achieve smooth speed transitions.To address this issue,a BP-PID speed control algorithm is designed,which dynamically adjusts fan speed based on indoor temperature changes.Experimental validation demonstrates that the designed system can achieve smooth speed transitions compared to traditional fan systems while maintaining stable indoor temperatures.Furthermore,the real-time responsiveness of the system is crucial for enhancing user comfort.Our research not only demonstrates the feasibility of temperature-based fan speed optimization strategies in both theory and practice but also provides valuable insights for energy management in future smart home environments.Ultimately,this research outcome will facilitate the development of smart home systems and have a positive impact on environmental sustainability.

Plutonium utilization in a small modular molten-salt reactor based on a batch fuel reprocessing scheme

A molten salt reactor(MSR)has outstanding features considering the application of thorium fuel,inherent safety,sustainability,and resistance to proliferation.However,fissile material^(233)U is significantly rare at the current stage,thus it is difficult for MSR to achieve a pure thorium-uranium fuel cycle.Therefore,using plutonium or enriched uranium as the initial fuel for MSR is more practical.In this study,we aim to verify the feasibility of a small modular MSR that utilizes plutonium as the starting fuel(SM-MSR-Pu),and highlight its advantages and disadvantages.First,the structural design and fuel management scheme of the SM-MSR-Pu were presented.Second,the neutronic characteristics,such as the graphite-irradiation lifetime,burn-up performance,and coefficient of temperature reactivity were calculated to analyze the physical characteristics of the SM-MSR-Pu.The results indicate that plutonium is a feasible and advantageous starting fuel for a SM-MSR;however,there are certain shortcomings that need to be solved.In a 250 MWth SM-MSR-Pu,approximately 288.64 kg^(233)U of plutonium with a purity of greater than 90% is produced while 978.00 kg is burned every ten years.The temperature reactivity coefficient decreases from -4.0 to -6.5 pcm K^(-1) over the 50-year operating time,which ensures a long-term safe operation.However,the amount of plutonium and accumulation of minor actinides(MAs)would increase as the burn-up time increases,and the annual production and purity of^(233)U will decrease.To achieve an optimal burn-up performance,setting the entire operation time to 30 years is advisable.Regardless,more than 3600 kg of plutonium eventually accumulate in the core.Further research is required to effectively utilize this accumulated plutonium.

Developed mathematical technique for fractional stochastic point kinetics model in nuclear reactor dynamics

Fractional stochastic kinetics equations have proven to be valuable tools for the point reactor kinetics model, where the nuclear reactions are not fully described by deterministic relations. A fractional stochastic model for the point kinetics system with multi-group of precursors,including the effect of temperature feedback, has been developed and analyzed. A major mathematical and inflexible scheme to the point kinetics model is obtained by merging the fractional and stochastic technique. A novel split-step method including mathematical tools of the Laplace transforms, Mittage–Leffler function, eigenvalues of the coefficient matrix, and its corresponding eigenvectors have been used for the fractional stochastic matrix differential equation. The validity of the proposed technique has been demonstrated via calculations of the mean and standard deviation of neutrons and precursor populations for various reactivities: step, ramp, sinusoidal, and temperature reactivity feedback. The results of the proposed method agree well with the conventional one of the deterministic point kinetics equations.

On the Nonlinear Response of Lower Stratospheric Ozone to External Forces——The Inclusion of BrO_x and Radiation Processes

In this paper the bromine family and radiative effects are considered in an updated box model under the framework of ozone temperature feedback, in order to further analyze the possible behavior of atmospheric ozone in the lower mid-latitude stratosphere. Results show that this updated photochemical system can present several different solutions, within a certain domain of parameters, with fixed-point and periodic states appearing in turn. The temperature feedback effect introduced in this box model has not changed the topology of the ozone system. This result presents nonlinear characteristics of the ozone system, and possible trends in the stratospheric atmosphere between complex chemistry and radiation processes.

Thermal perception method of virtual chemistry experiments

Background With the aim of addressing the difficulty in identifying temperatures in virtual chemistry experiments,we propose a temperature-sensing simulation method of virtual chemistry experiments.Methods We construct a virtual chemistry experiment temperature simulation platform,based on which a wearable temperature generation device is developed.The typical middle school virtual experiments of concentrated sulfuric acid dilution and ammonium nitrate dissolution are conducted to verify the actual effect of the device.Results The platform is capable to indicate near real-world experimental situations.The performance of the device not only meets the temperature sensing characteristics of human skin,but also matches the temperature change of virtual chemistry experiments in real-time.Conclusions It is demonstrated that this temperature-sensing simulation method can represent exothermic or endothermic chemistry experiments,which is beneficial for students to gain understanding of the principles of thermal energy transformation in chemical reactions,thus avoiding the danger that may be posed in the course of traditional teaching of chemistry experiments effectively.Although this method does not have a convenient enough operation for users,the immersion of virtual chemical experiments can be enhanced.

Analysis of thermal-mechanical coupled characteristics of vehicle twin-tube shock absorber

A comprehensive model that included mechanical dynamics of the shock absorber coupled with its thermal properties was proposed innovatively.Moreover a thermal-mechanical coupled model which reflected the closed-loop positive feedback system was established by using MATLAB/SIMULINK,and some curves of shock absorber temperature rising characteristic were obtained by simulation ＆computation under several operating modes and different parameters conditions.Research results show that：shock absorber design parameters,external excitations,and thermo-physical properties parameter,such as oil density have effect on the shock absorber temperature rising characteristic.However other thermo-physical properties parameters,such as oil specific heat,cylinder density,cylinder specific heat,and cylinder thermal conductivity,have no effect on it.The results may be used for studying reliability design of the shock absorber.

Active Control of Thermo-mechanical Buckling of Composite Laminated Plates Using Piezoelectric Actuators

This paper is concerned with the active control of thermomechanical buckling of composite laminated plates using piezoelectric facesheets as actuators.The four-variable trigonometric shear deformation theory and Hamilto's principle are applied to formulate the governing equation of structural system.The temperature feedback control strategy is proposed to conduct the active control of thermal-mechanical buckling.The simulation results show that the thermo-mechanical buckling of composite laminated plates can be effectively controlled by the presented control method.With a specific control gain,the critical mechanical buckling load can remain constant at different temperatures.The effects of geometric parameters,fiber angle,stacking sequence,position of piezoelectric layer and boundary conditions on the active control of thermo-mechanical buckling are also investigated.