A soil temperature control system was designed for sapling study in alpine region and tested in summer, 2009. The system consisted of a power switch, voltage regulator, microcomputer timer, safety relays, temperature ...A soil temperature control system was designed for sapling study in alpine region and tested in summer, 2009. The system consisted of a power switch, voltage regulator, microcomputer timer, safety relays, temperature control device, temperature sensors, heating cables, fireproofing plastic pipes (PVC), 108 heavy-duty plastic containers and seedlings. The heating cables were held in six 2-layer PVC frames with 25 cm wide, 320 cm long and 25 cm high and three 1-layer frames with 25 cm wide and 320 cm long for 15°C soil temperature treatment, half of the 2-layer frames were used for 20°C and 25°C soil temperature treatments, respectively. Each of the frames was installed at each of ditches with 30 cm wide, 330 cm long and 30 cm deep in size. 12 seedling containers with 20 cm top diameter, 18cm bottom diameter and 25 cm high were homogenously placed at each of the ditches, and spaces between the containers were filled with natural soil. The system was economic, and could increase soil temperatures obviously and uniformly, the maximal and minimal standard errors of soil temperatures were ±0.28 and ±0.05°C at 10cm depth in the containers within each of all the ditches. In the system, aboveground environment was natural, diurnal and monthly soil temperatures varied with changing air temperature, the research results may be better to know the eco-physiological and growth responses of alpine saplings/seedlings to soil warming than that in greenhouse, laboratory, infrared heat lamp and open top chamber.展开更多
A finite-time stabilization controller for the heating furnace temperature control system is proposed.Based on the extended Lyapunov finite-time stability theory and power integral method,a finite-time stable conditio...A finite-time stabilization controller for the heating furnace temperature control system is proposed.Based on the extended Lyapunov finite-time stability theory and power integral method,a finite-time stable condition of the heating furnace temperature control system is given.The temperature of the heating furnace is directed by the finite-time stabilization controller to make it stable in finite time.And the quality and quantity of slabs is improved.The simulation example is presented to illustrate the applicability of the developed results.展开更多
The component widely used in the intelligent temperature control system is the STC89C52 single-chip microcomputer, which is combined with the corresponding DS18B20 digital temperature sensor. The upper and lower limit...The component widely used in the intelligent temperature control system is the STC89C52 single-chip microcomputer, which is combined with the corresponding DS18B20 digital temperature sensor. The upper and lower limits of the corresponding temperature are obtained by the mutual fusion of the two types of equipment, thus realizing the purpose of intelligent temperature control. Therefore, the relay equipment can also judge whether to select to open the relay protection function based on the commands it executes. In the injection mold, the temperature control system uses a single-chip microcomputer, which controls various equipment to ensure the flexibility of the system and facilitate the use of relevant personnel, and also forms a simple control situation. In the application process, the temperature can also be judged, so as to control the corresponding technical indexes, improve the product quality and optimize the temperature control capability. In order to ensure the smooth implementation of the relevant work, intelligent control technology has been widely used in the design of injection mold and has also been widely used in various fields.展开更多
The magnetic field is one of the most important parameters in solar physics,and a polarimeter is the key device to measure the solar magnetic field.Liquid crystals based Stokes polarimeter is a novel technology,and wi...The magnetic field is one of the most important parameters in solar physics,and a polarimeter is the key device to measure the solar magnetic field.Liquid crystals based Stokes polarimeter is a novel technology,and will be applied for magnetic field measurement in the first space-based solar observatory satellite developed by China,Advanced Space-based Solar Observatory.However,the liquid crystals based Stokes polarimeter in space is not a mature technology.Therefore,it is of great scientific significance to study the control method and characteristics of the device.The retardation produced by a liquid crystal variable retarder is sensitive to the temperature,and the retardation changes 0.09°per 0.10℃.The error in polarization measurement caused by this change is 0.016,which affects the accuracy of magnetic field measurement.In order to ensure the stability of its performance,this paper proposes a high-precision temperature control system for liquid crystals based Stokes polarimeter in space.In order to optimize the structure design and temperature control system,the temperature field of liquid crystals based Stokes polarimeter is analyzed by the finite element method,and the influence of light on the temperature field of the liquid crystal variable retarder is analyzed theoretically.By analyzing the principle of highprecision temperature measurement in space,a high-precision temperature measurement circuit based on integrated operational amplifier,programmable amplifier and 12 bit A/D is designed,and a high-precision space temperature control system is developed by applying the integral separation PI temperature control algorithm and PWM driving heating films.The experimental results show that the effect of temperature control is accurate and stable,whenever the liquid crystals based Stokes polarimeter is either in the air or vacuum.The temperature stability is within±0.0150℃,which demonstrates greatly improved stability for the liquid crystals based Stokes polarimeter.展开更多
A new intelligent temperature control system for stove was introduced. It could accomplish A/D conversion, data processing, output displaying and alarming while the temperature exceeds the given threshold. The tempera...A new intelligent temperature control system for stove was introduced. It could accomplish A/D conversion, data processing, output displaying and alarming while the temperature exceeds the given threshold. The temperature adjusting devices were bi direction SCR and heating resistor. The hardware and software were discussed in the paper.展开更多
Vehicle hydraulic pump station, often work environment is poor, the environment temperature difference is very big, the natureof the hydraulic oil is affected by temperature is very big, a lot of damage, PLC automatic...Vehicle hydraulic pump station, often work environment is poor, the environment temperature difference is very big, the natureof the hydraulic oil is affected by temperature is very big, a lot of damage, PLC automatic control scheme and design of pumping station, the oiltemperature automatic control system realized the automation of the oil temperature control, greatly improving the pump station of the outdoorenvironment to adapt to the performance.展开更多
The liquid cooling system(LCS)of fuel cells is challenged by significant time delays,model uncertainties,pump and fan coupling,and frequent disturbances,leading to overshoot and control oscillations that degrade tempe...The liquid cooling system(LCS)of fuel cells is challenged by significant time delays,model uncertainties,pump and fan coupling,and frequent disturbances,leading to overshoot and control oscillations that degrade temperature regulation performance.To address these challenges,we propose a composite control scheme combining fuzzy logic and a variable-gain generalized supertwisting algorithm(VG-GSTA).Firstly,a one-dimensional(1D)fuzzy logic controler(FLC)for the pump ensures stable coolant flow,while a two-dimensional(2D)FLC for the fan regulates the stack temperature near the reference value.The VG-GSTA is then introduced to eliminate steady-state errors,offering resistance to disturbances and minimizing control oscillations.The equilibrium optimizer is used to fine-tune VG-GSTA parameters.Co-simulation verifies the effectiveness of our method,demonstrating its advantages in terms of disturbance immunity,overshoot suppression,tracking accuracy and response speed.展开更多
Maintaining stable high temperatures under pressure remains a challenge in high-pressure,high-temperature experiments using multi-anvil presses(MAPs).Temperature fluctuations exceeding 10℃ at high pressures are commo...Maintaining stable high temperatures under pressure remains a challenge in high-pressure,high-temperature experiments using multi-anvil presses(MAPs).Temperature fluctuations exceeding 10℃ at high pressures are common and particularly problematic with LaCrO_(3) heaters,which can experience significant power fluctuations and even failure due to substantial resistance changes—an issue conventional thyristorcontrolled heating systems cannot effectively manage.To address this limitation,we have developed the Multi-Anvil Stable Temperature controller(MASTer),a high-performance heating system optimized for MAP experiments.MASTer enables precise,high-speed measurement of heating parameters and power output control,incorporating a gentle regulation strategy to enhance stability.It ensures consistent heating across various heater types,including LaCrO_(3),with power fluctuations limited to±0.1 W and temperature fluctuations to within±2℃ in most cases.The design,operating principles,user interface,functionality,and performance of the heating system are discussed in detail.展开更多
Dividing wall batch distillation with middle vessel(DWBDM)is a new type of batch distillation column,with outstanding advantages of low capital cost,energy saving and flexible operation.However,temperature control of ...Dividing wall batch distillation with middle vessel(DWBDM)is a new type of batch distillation column,with outstanding advantages of low capital cost,energy saving and flexible operation.However,temperature control of DWBDM process is challenging,since inherently dynamic and highly nonlinear,which make it difficult to give the controller reasonable set value or optimal temperature profile for temperature control scheme.To overcome this obstacle,this study proposes a new strategy to develop temperature control scheme for DWBDM combining neural network soft-sensor with fuzzy control.Dynamic model of DWBDM was firstly developed and numerically solved by Python,with three control schemes:composition control by PID and fuzzy control respectively,and temperature control by fuzzy control with neural network soft-sensor.For dynamic process,the neural networks with memory functions,such as RNN,LSTM and GRU,are used to handle with time-series data.The results from a case example show that the new control scheme can perform a good temperature control of DWBDM with the same or even better product purities as traditional PID or fuzzy control,and fuzzy control could reduce the effect of prediction error from neural network,indicating that it is a highly feasible and effective control approach for DWBDM,and could even be extended to other dynamic processes.展开更多
Accurate skin temperature is one of the critical factors in successfully assimilating satellite radiance data over land.However,model-simulated skin temperature may not be accurate enough.To address this issue,an exte...Accurate skin temperature is one of the critical factors in successfully assimilating satellite radiance data over land.However,model-simulated skin temperature may not be accurate enough.To address this issue,an extended skin temperature control variable(TSCV) approach is proposed in a variational assimilation framework,which also considers the background error correlation between skin temperature and atmospheric variables.A series of single observation tests and a 10-day cycling assimilation experiment were conducted to evaluate the impact of the TSCV approach on the assimilation of AMSU-A and ATMS(Advanced Technology Microwave Sounder) microwave temperature-sounding channels over land.The results of the single observation tests show that by applying the TSCV approach,not only the direct analysis of skin temperature is realized,but also the interaction between skin temperature and atmospheric variables can be achieved during the assimilation process.The results of the cycling experiment demonstrate that the TSCV approach improves the skin temperature analysis,which in turn reduces the RMSE of the surface variables and low-level air temperature forecasts.The TSCV approach also reduces the difference between the observed and simulated brightness temperatures of both microwave and infrared window channels over land,suggesting that the approach can facilitate the radiance simulation of these channels,thus contributing to the assimilation of window channels.展开更多
With the development of space-based remote sensing and deep space exploration technology,higher standards for temperature stability and uniformity of payloads have been proposed to spacecraft thermal control systems.A...With the development of space-based remote sensing and deep space exploration technology,higher standards for temperature stability and uniformity of payloads have been proposed to spacecraft thermal control systems.As an efficient two-phase heat transfer device with active temperature control capabilities,the loop heat pipe(LHP)can be widely applied in spacecraft thermal control systems to achieve reliable temperature control under various operating modes and complex space thermal environments.This paper analyzes the fundamental theories of thermal switch-controlled,reservoir temperature-controlled,and bypass valve-controlled LHPs.The focus is on the theories and methods of achieving high-precision and high-reliability temperature control via active reservoir temperature control.Novel control techniques in recent years,such as non-condensable gas(NCG)control with a temperature stability of 0.01℃ ,are also briefly introduced as promising approaches to improve LHP performance.The on-orbit performance and characteristics of various LHP temperature control methods are provided and ranked in terms of control precision,energy consumption,complexity,and weight.Thermoelectric cooler(TEC)/electrical heater,as the foundation of reservoir temperature control,can achieve a temperature stability of in space applications under±0.2℃ a wide range of heat load.Microgravity model,control strategy,and operating mode conversion are three optimization directions that would hopefully further expand the application scenario of reservoir temperature control.Specific design principles and challenges for corresponding directions are summarized as guidance for researchers.展开更多
Closed production systems,such as plant factories and vertical farms,have emerged to ensure a sustainable supply of fresh food,to cope with the increasing consumption of natural resource for the growing population.In ...Closed production systems,such as plant factories and vertical farms,have emerged to ensure a sustainable supply of fresh food,to cope with the increasing consumption of natural resource for the growing population.In a plant factory,a microclimate model is one of the direct control components of a whole system.In order to better realize the dynamic regulation for the microclimate model,energy-saving and consumption reduction,it is necessary to optimize the environmental parameters in the plant factory,and thereby to determine the influencing factors of atmosphere control systems.Therefore,this study aims to identify accurate microclimate models,and further to predict temperature change based on the experimental data,using the classification and regression trees(CART)algorithm.A random forest theory was used to represent the temperature control system.A mechanism model of the temperature control system was proposed to improve the performance of the plant factories.In terms of energy efficiency,the main influencing factors on temperature change in the plant factories were obtained,including the temperature and air volume flow of the temperature control device,as well as the internal relative humidity.The generalization error of the prediction model can reach 0.0907.The results demonstrated that the proposed model can present the quantitative relationship and prediction function.This study can provide a reference for the design of high-precision environmental control systems in plant factories.展开更多
Considering some characteristics of large-scale standing quench furnace, such as great heat inertia, evident time lag, strong coupling influence, hard to establish exact mathematical models of plant and etc, an artifi...Considering some characteristics of large-scale standing quench furnace, such as great heat inertia, evident time lag, strong coupling influence, hard to establish exact mathematical models of plant and etc, an artificial intelligent fuzzy control algorithm is put forward in this paper. Through adjusting the on-off ratio of electric heating elements, the temperature in furnace is controlled accurately. This paper describes structure and qualities of the large-scale standing quench furnace briefly, introduces constitution of control system, and expounds principle and implementation of intelligent control algorithm. The applied results prove that the intelligent control system can completely satisfy the technological requirements. Namely, it can realize fast increasing temperature with a little overshoot, exact holding temperature, and well-distributed temperature in quench furnace. It has raised the output and quality of aluminum material, and brought the outstanding economic and social benefits.展开更多
Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern microelectronics.However,this inevitably exac-erbates the inhomogeneity ...Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern microelectronics.However,this inevitably exac-erbates the inhomogeneity of temperature distribution in microsystems,making precise temperature control for electronic components extremely challenging.Herein,we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50×50μm^(2),which are fabricated from dense and flat freestanding Bi2Te3-based ther-moelectric nano films deposited on a newly developed nano graphene oxide membrane substrate.Its tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics.A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445μW,resulting in an ultrahigh temperature control capability over 100 K mW^(-1).Moreover,an ultra-fast cooling rate exceeding 2000 K s^(-1) and excellent reliability of up to 1 million cycles are observed.Our proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics.展开更多
It is important and difficult to control the temperature of mass concrete structure during high arch dam construction.A new method with decision support system is presented for temperature control and crack prevention...It is important and difficult to control the temperature of mass concrete structure during high arch dam construction.A new method with decision support system is presented for temperature control and crack prevention.It is a database system with functions of data storage,information inquiry,data analysis,early warning and resource sharing.Monitoring information during construction can be digitized via this system,and the intelligent analysis and dynamic control of concrete temperature can be conducted.This method has been applied in the construction of the Dagangshan Arch Dam in China and has proven to be very convenient.Based on the decision support of this system and the dynamic adjustment of construction measures,the concrete temperature of this project is well-controlled.展开更多
Color-changing fabric system with temperature control is designed through textile design and electronic technology.The system inserts a conductive fabric inside a fabric coated with thermochromic powder.A temperature ...Color-changing fabric system with temperature control is designed through textile design and electronic technology.The system inserts a conductive fabric inside a fabric coated with thermochromic powder.A temperature control system is constructed to adjust the current to raise the temperature of conductive fabric to the active point of thermochromic powder and keep the temperature in stable.Therefore,the fabric could sense the temperature and change colors.In order to achieve wearability,mobile power supply is selected and flexible sensor is adopted.Kalman filter is engaged in the proportion integration differentiation(PID)control algorithm to reduce the interference of measurement noise.The experiment result shows that the proposed color-changing fabric system could reach the target temperature quickly and meet the design demands for color-changing.展开更多
Cryogenic machining is a new technology which makes use of the special mechanicalprcperties of niaterials in a cryogenic or a 'super cold' state for machining. The control of acryogenic machining system(CMS)i...Cryogenic machining is a new technology which makes use of the special mechanicalprcperties of niaterials in a cryogenic or a 'super cold' state for machining. The control of acryogenic machining system(CMS)is one of the key problems which need to be solved for practi-cal cryogenic machining A temperature field control principle is presented which calculates theheat source temperature in the light of the tool temperature field information, and a control mod-el of three-dimensional dynamic temperature field for CMS is established, and the boundary con-ditions and the heat source of temperature field in orthogonal cutting are discussed. Based on theinvestigation of the control feature and technique. a prototype system for controlling CMS is crea-ted.展开更多
Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nu...Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nutrient solution is the key to obtain high quality and high yield of hydroponic vegetables over summer. With Lactuca sativa vat. crispa ＇Luosheng No.3＇ as the test material, the effect of chiller cooling technology on the temperature of nutrient solution, as well as on the yield and quality of Luosheng No.3, in over-summer hydroponic cultivation was studied. The results showed that the chiller cooling technology controlled the nutrient solution temperature in a reasonable range （（20 ± 1）℃） and promoted the growth and dry matter accumulation of Luosheng No.3, instead of affecting the quality. In short, the chiller cooling technology is applicable to the temperature regulation of nutrient solu- tion in hydroponics over summer.展开更多
In order to incorporate the decision maker＇s preference into multiobjective optimization a preference-based multiobjective artificial bee colony algorithm PMABCA is proposed.In the proposed algorithm a novel referenc...In order to incorporate the decision maker＇s preference into multiobjective optimization a preference-based multiobjective artificial bee colony algorithm PMABCA is proposed.In the proposed algorithm a novel reference point based preference expression method is addressed.The fitness assignment function is defined based on the nondominated rank and the newly defined preference distance.An archive set is introduced for saving the nondominated solutions and an improved crowding-distance operator is addressed to remove the extra solutions in the archive.The experimental results of two benchmark test functions show that a preferred set of solutions and some other non-preference solutions are achieved simultaneously.The simulation results of the proportional-integral-derivative PID parameter optimization for superheated steam temperature verify that the PMABCA is efficient in aiding to making a reasonable decision.展开更多
This paper presents a brief summary of the three development stages of investigation on the transpiration cooling and its control for aircraft, missiles and electromagnetic gun, then the control problem of the distrib...This paper presents a brief summary of the three development stages of investigation on the transpiration cooling and its control for aircraft, missiles and electromagnetic gun, then the control problem of the distributed parameters system with a moving boundary is derived. It introduces the mathematical model of the transpiration cooling control, its control characteristics, and the present situation of the experimental and theoretical study on this problem. This paper also describes the main study results and the existing problems. The prospective application is also reported. The major references in every developing stage are listed systematically for further study.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 30872000 and 41071203)partially supported by the Project of Knowledge Innovation, Chinese Academy of Sciences (No. KZXZ-YW-33)Sichuan Foundation of Excellent Young Scientists (No. 2010JQ0026)
文摘A soil temperature control system was designed for sapling study in alpine region and tested in summer, 2009. The system consisted of a power switch, voltage regulator, microcomputer timer, safety relays, temperature control device, temperature sensors, heating cables, fireproofing plastic pipes (PVC), 108 heavy-duty plastic containers and seedlings. The heating cables were held in six 2-layer PVC frames with 25 cm wide, 320 cm long and 25 cm high and three 1-layer frames with 25 cm wide and 320 cm long for 15°C soil temperature treatment, half of the 2-layer frames were used for 20°C and 25°C soil temperature treatments, respectively. Each of the frames was installed at each of ditches with 30 cm wide, 330 cm long and 30 cm deep in size. 12 seedling containers with 20 cm top diameter, 18cm bottom diameter and 25 cm high were homogenously placed at each of the ditches, and spaces between the containers were filled with natural soil. The system was economic, and could increase soil temperatures obviously and uniformly, the maximal and minimal standard errors of soil temperatures were ±0.28 and ±0.05°C at 10cm depth in the containers within each of all the ditches. In the system, aboveground environment was natural, diurnal and monthly soil temperatures varied with changing air temperature, the research results may be better to know the eco-physiological and growth responses of alpine saplings/seedlings to soil warming than that in greenhouse, laboratory, infrared heat lamp and open top chamber.
文摘A finite-time stabilization controller for the heating furnace temperature control system is proposed.Based on the extended Lyapunov finite-time stability theory and power integral method,a finite-time stable condition of the heating furnace temperature control system is given.The temperature of the heating furnace is directed by the finite-time stabilization controller to make it stable in finite time.And the quality and quantity of slabs is improved.The simulation example is presented to illustrate the applicability of the developed results.
文摘The component widely used in the intelligent temperature control system is the STC89C52 single-chip microcomputer, which is combined with the corresponding DS18B20 digital temperature sensor. The upper and lower limits of the corresponding temperature are obtained by the mutual fusion of the two types of equipment, thus realizing the purpose of intelligent temperature control. Therefore, the relay equipment can also judge whether to select to open the relay protection function based on the commands it executes. In the injection mold, the temperature control system uses a single-chip microcomputer, which controls various equipment to ensure the flexibility of the system and facilitate the use of relevant personnel, and also forms a simple control situation. In the application process, the temperature can also be judged, so as to control the corresponding technical indexes, improve the product quality and optimize the temperature control capability. In order to ensure the smooth implementation of the relevant work, intelligent control technology has been widely used in the design of injection mold and has also been widely used in various fields.
基金the National Natural Science Foundation of China(Grant Nos.11427803,11427901 and 11773040)the Strategic Pioneer Program on Space Science,Chinese Academy of Sciences(CAS)(XDA04061002 and XDA15010800)the Public Technology Service Center,National Astronomical Observatories of CAS(829011V01)。
文摘The magnetic field is one of the most important parameters in solar physics,and a polarimeter is the key device to measure the solar magnetic field.Liquid crystals based Stokes polarimeter is a novel technology,and will be applied for magnetic field measurement in the first space-based solar observatory satellite developed by China,Advanced Space-based Solar Observatory.However,the liquid crystals based Stokes polarimeter in space is not a mature technology.Therefore,it is of great scientific significance to study the control method and characteristics of the device.The retardation produced by a liquid crystal variable retarder is sensitive to the temperature,and the retardation changes 0.09°per 0.10℃.The error in polarization measurement caused by this change is 0.016,which affects the accuracy of magnetic field measurement.In order to ensure the stability of its performance,this paper proposes a high-precision temperature control system for liquid crystals based Stokes polarimeter in space.In order to optimize the structure design and temperature control system,the temperature field of liquid crystals based Stokes polarimeter is analyzed by the finite element method,and the influence of light on the temperature field of the liquid crystal variable retarder is analyzed theoretically.By analyzing the principle of highprecision temperature measurement in space,a high-precision temperature measurement circuit based on integrated operational amplifier,programmable amplifier and 12 bit A/D is designed,and a high-precision space temperature control system is developed by applying the integral separation PI temperature control algorithm and PWM driving heating films.The experimental results show that the effect of temperature control is accurate and stable,whenever the liquid crystals based Stokes polarimeter is either in the air or vacuum.The temperature stability is within±0.0150℃,which demonstrates greatly improved stability for the liquid crystals based Stokes polarimeter.
文摘A new intelligent temperature control system for stove was introduced. It could accomplish A/D conversion, data processing, output displaying and alarming while the temperature exceeds the given threshold. The temperature adjusting devices were bi direction SCR and heating resistor. The hardware and software were discussed in the paper.
文摘Vehicle hydraulic pump station, often work environment is poor, the environment temperature difference is very big, the natureof the hydraulic oil is affected by temperature is very big, a lot of damage, PLC automatic control scheme and design of pumping station, the oiltemperature automatic control system realized the automation of the oil temperature control, greatly improving the pump station of the outdoorenvironment to adapt to the performance.
基金Supported by the Major Science and Technology Project of Jilin Province(20220301010GX)the International Scientific and Technological Cooperation(20240402071GH).
文摘The liquid cooling system(LCS)of fuel cells is challenged by significant time delays,model uncertainties,pump and fan coupling,and frequent disturbances,leading to overshoot and control oscillations that degrade temperature regulation performance.To address these challenges,we propose a composite control scheme combining fuzzy logic and a variable-gain generalized supertwisting algorithm(VG-GSTA).Firstly,a one-dimensional(1D)fuzzy logic controler(FLC)for the pump ensures stable coolant flow,while a two-dimensional(2D)FLC for the fan regulates the stack temperature near the reference value.The VG-GSTA is then introduced to eliminate steady-state errors,offering resistance to disturbances and minimizing control oscillations.The equilibrium optimizer is used to fine-tune VG-GSTA parameters.Co-simulation verifies the effectiveness of our method,demonstrating its advantages in terms of disturbance immunity,overshoot suppression,tracking accuracy and response speed.
基金supported by the National Science Fund for Distinguished Young Scholars(Grant No.T2225027)the National Key R&D Program of China(Grant No.2023YFA1608902).
文摘Maintaining stable high temperatures under pressure remains a challenge in high-pressure,high-temperature experiments using multi-anvil presses(MAPs).Temperature fluctuations exceeding 10℃ at high pressures are common and particularly problematic with LaCrO_(3) heaters,which can experience significant power fluctuations and even failure due to substantial resistance changes—an issue conventional thyristorcontrolled heating systems cannot effectively manage.To address this limitation,we have developed the Multi-Anvil Stable Temperature controller(MASTer),a high-performance heating system optimized for MAP experiments.MASTer enables precise,high-speed measurement of heating parameters and power output control,incorporating a gentle regulation strategy to enhance stability.It ensures consistent heating across various heater types,including LaCrO_(3),with power fluctuations limited to±0.1 W and temperature fluctuations to within±2℃ in most cases.The design,operating principles,user interface,functionality,and performance of the heating system are discussed in detail.
基金supported by Beijing Natural Science Foundation(2222037)the Special Educating Project of the Talent for Carbon Peak and Carbon Neutrality of University of Chinese Academy of Sciences(Innovation of talent cultivation model for“dual carbon”in chemical engineering industry,E3E56501A2).
文摘Dividing wall batch distillation with middle vessel(DWBDM)is a new type of batch distillation column,with outstanding advantages of low capital cost,energy saving and flexible operation.However,temperature control of DWBDM process is challenging,since inherently dynamic and highly nonlinear,which make it difficult to give the controller reasonable set value or optimal temperature profile for temperature control scheme.To overcome this obstacle,this study proposes a new strategy to develop temperature control scheme for DWBDM combining neural network soft-sensor with fuzzy control.Dynamic model of DWBDM was firstly developed and numerically solved by Python,with three control schemes:composition control by PID and fuzzy control respectively,and temperature control by fuzzy control with neural network soft-sensor.For dynamic process,the neural networks with memory functions,such as RNN,LSTM and GRU,are used to handle with time-series data.The results from a case example show that the new control scheme can perform a good temperature control of DWBDM with the same or even better product purities as traditional PID or fuzzy control,and fuzzy control could reduce the effect of prediction error from neural network,indicating that it is a highly feasible and effective control approach for DWBDM,and could even be extended to other dynamic processes.
基金sponsored by the National Natural Science Foundation of China(Grant No.42075148)the High-Performance Computing Center of Nanjing University of Information Science & Technology for supporting this work。
文摘Accurate skin temperature is one of the critical factors in successfully assimilating satellite radiance data over land.However,model-simulated skin temperature may not be accurate enough.To address this issue,an extended skin temperature control variable(TSCV) approach is proposed in a variational assimilation framework,which also considers the background error correlation between skin temperature and atmospheric variables.A series of single observation tests and a 10-day cycling assimilation experiment were conducted to evaluate the impact of the TSCV approach on the assimilation of AMSU-A and ATMS(Advanced Technology Microwave Sounder) microwave temperature-sounding channels over land.The results of the single observation tests show that by applying the TSCV approach,not only the direct analysis of skin temperature is realized,but also the interaction between skin temperature and atmospheric variables can be achieved during the assimilation process.The results of the cycling experiment demonstrate that the TSCV approach improves the skin temperature analysis,which in turn reduces the RMSE of the surface variables and low-level air temperature forecasts.The TSCV approach also reduces the difference between the observed and simulated brightness temperatures of both microwave and infrared window channels over land,suggesting that the approach can facilitate the radiance simulation of these channels,thus contributing to the assimilation of window channels.
基金funded by National Outstanding Youth Foundation of China,grant number 2020-JCJQ-ZQ-042.
文摘With the development of space-based remote sensing and deep space exploration technology,higher standards for temperature stability and uniformity of payloads have been proposed to spacecraft thermal control systems.As an efficient two-phase heat transfer device with active temperature control capabilities,the loop heat pipe(LHP)can be widely applied in spacecraft thermal control systems to achieve reliable temperature control under various operating modes and complex space thermal environments.This paper analyzes the fundamental theories of thermal switch-controlled,reservoir temperature-controlled,and bypass valve-controlled LHPs.The focus is on the theories and methods of achieving high-precision and high-reliability temperature control via active reservoir temperature control.Novel control techniques in recent years,such as non-condensable gas(NCG)control with a temperature stability of 0.01℃ ,are also briefly introduced as promising approaches to improve LHP performance.The on-orbit performance and characteristics of various LHP temperature control methods are provided and ranked in terms of control precision,energy consumption,complexity,and weight.Thermoelectric cooler(TEC)/electrical heater,as the foundation of reservoir temperature control,can achieve a temperature stability of in space applications under±0.2℃ a wide range of heat load.Microgravity model,control strategy,and operating mode conversion are three optimization directions that would hopefully further expand the application scenario of reservoir temperature control.Specific design principles and challenges for corresponding directions are summarized as guidance for researchers.
文摘Closed production systems,such as plant factories and vertical farms,have emerged to ensure a sustainable supply of fresh food,to cope with the increasing consumption of natural resource for the growing population.In a plant factory,a microclimate model is one of the direct control components of a whole system.In order to better realize the dynamic regulation for the microclimate model,energy-saving and consumption reduction,it is necessary to optimize the environmental parameters in the plant factory,and thereby to determine the influencing factors of atmosphere control systems.Therefore,this study aims to identify accurate microclimate models,and further to predict temperature change based on the experimental data,using the classification and regression trees(CART)algorithm.A random forest theory was used to represent the temperature control system.A mechanism model of the temperature control system was proposed to improve the performance of the plant factories.In terms of energy efficiency,the main influencing factors on temperature change in the plant factories were obtained,including the temperature and air volume flow of the temperature control device,as well as the internal relative humidity.The generalization error of the prediction model can reach 0.0907.The results demonstrated that the proposed model can present the quantitative relationship and prediction function.This study can provide a reference for the design of high-precision environmental control systems in plant factories.
基金Supported by The National Natural Science Foundation of China (No. 59835170).
文摘Considering some characteristics of large-scale standing quench furnace, such as great heat inertia, evident time lag, strong coupling influence, hard to establish exact mathematical models of plant and etc, an artificial intelligent fuzzy control algorithm is put forward in this paper. Through adjusting the on-off ratio of electric heating elements, the temperature in furnace is controlled accurately. This paper describes structure and qualities of the large-scale standing quench furnace briefly, introduces constitution of control system, and expounds principle and implementation of intelligent control algorithm. The applied results prove that the intelligent control system can completely satisfy the technological requirements. Namely, it can realize fast increasing temperature with a little overshoot, exact holding temperature, and well-distributed temperature in quench furnace. It has raised the output and quality of aluminum material, and brought the outstanding economic and social benefits.
基金The authors thank D.Berger,D.Hofmann and C.Kupka in IFW Dresden for helpful technical support.H.R.acknowledges funding from the DFG(Deutsche Forschungsgemeinschaft)within grant number RE3973/1-1.Q.J.,H.R.and K.N.conceived the work.With the support from N.Y.and X.J.,Q.J.and T.G.fabricated the thermoelectric films and conducted the structural and compositional characterizations.Q.J.prepared microchips and fabricated the on-chip micro temperature controllers.Q.J.and N.P.carried out the temperature-dependent material and device performance measurements.Q.J.and H.R.performed the simulation and analytical calculations.Q.J.,H.R.and K.N.wrote the manuscript with input from the other coauthors.All the authors discussed the results and commented on the manuscript.
文摘Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern microelectronics.However,this inevitably exac-erbates the inhomogeneity of temperature distribution in microsystems,making precise temperature control for electronic components extremely challenging.Herein,we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50×50μm^(2),which are fabricated from dense and flat freestanding Bi2Te3-based ther-moelectric nano films deposited on a newly developed nano graphene oxide membrane substrate.Its tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics.A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445μW,resulting in an ultrahigh temperature control capability over 100 K mW^(-1).Moreover,an ultra-fast cooling rate exceeding 2000 K s^(-1) and excellent reliability of up to 1 million cycles are observed.Our proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics.
基金Supported by the National Natural Science Foundation of China(No.50909078)the National Basic Research Program of China("973"Program,No.2013CB035900)
文摘It is important and difficult to control the temperature of mass concrete structure during high arch dam construction.A new method with decision support system is presented for temperature control and crack prevention.It is a database system with functions of data storage,information inquiry,data analysis,early warning and resource sharing.Monitoring information during construction can be digitized via this system,and the intelligent analysis and dynamic control of concrete temperature can be conducted.This method has been applied in the construction of the Dagangshan Arch Dam in China and has proven to be very convenient.Based on the decision support of this system and the dynamic adjustment of construction measures,the concrete temperature of this project is well-controlled.
文摘Color-changing fabric system with temperature control is designed through textile design and electronic technology.The system inserts a conductive fabric inside a fabric coated with thermochromic powder.A temperature control system is constructed to adjust the current to raise the temperature of conductive fabric to the active point of thermochromic powder and keep the temperature in stable.Therefore,the fabric could sense the temperature and change colors.In order to achieve wearability,mobile power supply is selected and flexible sensor is adopted.Kalman filter is engaged in the proportion integration differentiation(PID)control algorithm to reduce the interference of measurement noise.The experiment result shows that the proposed color-changing fabric system could reach the target temperature quickly and meet the design demands for color-changing.
文摘Cryogenic machining is a new technology which makes use of the special mechanicalprcperties of niaterials in a cryogenic or a 'super cold' state for machining. The control of acryogenic machining system(CMS)is one of the key problems which need to be solved for practi-cal cryogenic machining A temperature field control principle is presented which calculates theheat source temperature in the light of the tool temperature field information, and a control mod-el of three-dimensional dynamic temperature field for CMS is established, and the boundary con-ditions and the heat source of temperature field in orthogonal cutting are discussed. Based on theinvestigation of the control feature and technique. a prototype system for controlling CMS is crea-ted.
基金Supported by Science and Technology Innovative Leading Fund of Ningxia Academy of Agriculture and Forestry Sciences(NKYZ-16-1101)~~
文摘Temperature, as an important feature of hydroponic nutrient solution, is closely related to dissolved oxygen content of nutrient solution and growth status of plant roots. How to precisely adjust the temperature of nutrient solution is the key to obtain high quality and high yield of hydroponic vegetables over summer. With Lactuca sativa vat. crispa ＇Luosheng No.3＇ as the test material, the effect of chiller cooling technology on the temperature of nutrient solution, as well as on the yield and quality of Luosheng No.3, in over-summer hydroponic cultivation was studied. The results showed that the chiller cooling technology controlled the nutrient solution temperature in a reasonable range （（20 ± 1）℃） and promoted the growth and dry matter accumulation of Luosheng No.3, instead of affecting the quality. In short, the chiller cooling technology is applicable to the temperature regulation of nutrient solu- tion in hydroponics over summer.
基金The National Natural Science Foundation of China(No.51306082,51476027)
文摘In order to incorporate the decision maker＇s preference into multiobjective optimization a preference-based multiobjective artificial bee colony algorithm PMABCA is proposed.In the proposed algorithm a novel reference point based preference expression method is addressed.The fitness assignment function is defined based on the nondominated rank and the newly defined preference distance.An archive set is introduced for saving the nondominated solutions and an improved crowding-distance operator is addressed to remove the extra solutions in the archive.The experimental results of two benchmark test functions show that a preferred set of solutions and some other non-preference solutions are achieved simultaneously.The simulation results of the proportional-integral-derivative PID parameter optimization for superheated steam temperature verify that the PMABCA is efficient in aiding to making a reasonable decision.
基金The Project is Supported by Nation Natural Science Foundation of China
文摘This paper presents a brief summary of the three development stages of investigation on the transpiration cooling and its control for aircraft, missiles and electromagnetic gun, then the control problem of the distributed parameters system with a moving boundary is derived. It introduces the mathematical model of the transpiration cooling control, its control characteristics, and the present situation of the experimental and theoretical study on this problem. This paper also describes the main study results and the existing problems. The prospective application is also reported. The major references in every developing stage are listed systematically for further study.
