The development of wearable technologies promotes the research of flexible sensors.It is hoped that a flexible sensor can collect different physiological data,such as temperature and respiratory rate(RR).The temperatu...The development of wearable technologies promotes the research of flexible sensors.It is hoped that a flexible sensor can collect different physiological data,such as temperature and respiratory rate(RR).The temperature of the exhaled gas is generally higher than that in the air,and the periodic change of temperature is related to the respiratory rate.In this work,we use platinum fiber and spandex fiber to prepare yarn-based temperature sensor with high tensile performance through hollow spindle wrapping spinning technology.After the measurement,the sensitivity of the sensor can reach at least 3.18×10^(-3)℃^(-1).We use the sensor and ordinary fabric mask to prepare a sensor mask that can monitor human respiratory signals to explore the performance of the sensor in RR measurement.The experimental results show that when measuring human RR,the yarn-based temperature sensor can accurately distinguish different respiratory states such as normal breathing,deep breathing,and rapid breathing while speaking.It is suggested that yarn-based temperature sensors can be used in medical fields such as real-time respiratory detection and temperature measurement.展开更多
This paper addresses some of the problems related to direct surface temperature measurement of a salient pole synchronous generator excitation winding in rotation. Excitation winding temperature is used for determinin...This paper addresses some of the problems related to direct surface temperature measurement of a salient pole synchronous generator excitation winding in rotation. Excitation winding temperature is used for determining the dynamic limit in a PQ diagram. The paper also addresses procedures of improving the accuracy of surface temperature measurement using the contact DS 18B20 digital temperature probes. The paper also provides experimental results of direct temperature measurement of the excitation winding surface conducted in the salient pole synchronous generator in the rotation.展开更多
The accuracy of temperature measurement is often reduced due to random noise in Raman-based distributed temperature sensor (RDTS). A noise reduction method based on a nonlinear filter is thus proposed in this paper. C...The accuracy of temperature measurement is often reduced due to random noise in Raman-based distributed temperature sensor (RDTS). A noise reduction method based on a nonlinear filter is thus proposed in this paper. Compared with the temperature demodulation results of raw signals, the proposed method in this paper can reduce the average maximum deviation of temperature measurement results from 4.1°C to 1.2°C at 40.0°C, 50.0°C and 60.0°C. And the proposed method in this paper can improve the accuracy of temperature measurement of Raman-based distributed temperature sensor better than the commonly used wavelet transform-based method. The advantages of the proposed method in improving the accuracy of temperature measurement for Raman-based distributed temperature sensor are quantitatively reflected in the maximum deviation and root mean square error of temperature measurement results. Therefore, this paper proposes an effective and feasible method to improve the accuracy of temperature measurement results for Raman-based distributed temperature sensor.展开更多
A highly sensitive optical fiber temperature sensor based on a section of liquid-filled silica capillary tube(SCT)between single mode fibers is proposed. Two micro-holes are drilled on two sides of SCT directly by usi...A highly sensitive optical fiber temperature sensor based on a section of liquid-filled silica capillary tube(SCT)between single mode fibers is proposed. Two micro-holes are drilled on two sides of SCT directly by using femtosecond laser micromachining, and liquid polymer is filled into the SCT through the micro-holes without any air bubbles and then sealed by using ultra-violet(UV) cure adhesive. The sidewall of the SCT forms a Fabry–Perot resonator, and loss peaks are achieved in the transmission spectrum of the SCT at the resonant wavelength. The resonance condition can be influenced by the refractive index variation of the liquid polymer filled in SCT, which is sensitive to temperature due to its high thermooptical coefficient(-2.98 × 10^-4℃^-1). The experimental result shows that the temperature sensitivity of the proposed fiber structure reaches 5.09 nm/℃ with a perfect linearity of 99.8%. In addition, it exhibits good repeatability and reliability in temperature sensing application.展开更多
Dynamic capacity increase in high voltage electric power transmission line is currently the most economical method for solving electric power transmission bottleneck nowadays. DS18B20 temperature sensor is applied to ...Dynamic capacity increase in high voltage electric power transmission line is currently the most economical method for solving electric power transmission bottleneck nowadays. DS18B20 temperature sensor is applied to the dynamic capacity increase of high voltage transmission lines to measure the conductor temperature and ambient temperature. The paper is focused on the experiment of DS18B20 both in the laboratory and outside. From the result of the lab temperature measurement data analysis, using 4 DS18B20’s is the most suitable plan, considering both accuracy and economical efficiency. In the experiment outside, we get four groups of conductor (uncharged) temperature and four groups of ambient temperature. The data proved that DS18B20 has good stability, and small measurement error. It is suitable for measuring the temperature of conductor and ambient in dynamic capacity increase, and helpful to improve the accuracy of the calculation of capacity increasing.展开更多
A novel system configuration of fiber optic sensor based on optical abso rption is proposed. Several compensation measures are discussed. A simulated exp eriment is designed and the output curve of system is given. Th...A novel system configuration of fiber optic sensor based on optical abso rption is proposed. Several compensation measures are discussed. A simulated exp eriment is designed and the output curve of system is given. The experiment al result shows that these compensation measures are effective on dynamic distu rbances which are caused by background light and optical fiber bend. In addition , the drifts in the light source intensity, fiber losses, and photodetector effi ciency are also compensated.展开更多
The principle of a new optical fiber temperature transducer is presented,and ingenious design scheme of this transducer is given.Because taking the special modulation and ratio measurement,this new transducer has prov...The principle of a new optical fiber temperature transducer is presented,and ingenious design scheme of this transducer is given.Because taking the special modulation and ratio measurement,this new transducer has provided with high characteristics:experimental transmitting distance is 500m;measurement error,in the measured temperature range of 0-250℃，,is less than ±0.5℃;power consumption of the probe is less than 300μW.Finally,some points of the experiment are given.展开更多
Taking a specific production process as an example, this paper introduces the design of multi slot and unequal temperature PID controller based on single chip microcomputer. The mathematical implementation method...Taking a specific production process as an example, this paper introduces the design of multi slot and unequal temperature PID controller based on single chip microcomputer. The mathematical implementation method of PID algorithm and the design method of the hardware and software are discussed, The principle diagram of the hardware circuit implementing the control algorithm and the features of the software possessed are also presented.展开更多
The inconsistent response curve of delicate micro/nanofiber(MNF)sensors during cycling measurement is one of the main factors which greatly limit their practical application.In this paper,we proposed a temperature sen...The inconsistent response curve of delicate micro/nanofiber(MNF)sensors during cycling measurement is one of the main factors which greatly limit their practical application.In this paper,we proposed a temperature sensor based on the copper rod-supported helical microfiber(HMF).The HMF sensors exhibited different light intensity-temperature response relationships in single-cycle measurements.Two neural networks,the deep belief network(DBN)and the backpropagation neural network(BPNN),were employed respectively to predict the temperature of the HMF sensor in different sensing processes.The input variables of the network were the sensor geometric parameters(the microfiber diameter,wrapped length,coiled turns,and helical angle)and the output optical intensity under different working processes.The root mean square error(RMSE)and Pearson correlation coefficient(R)were used to evaluate the predictive ability of the networks.The DBN with two restricted Boltzmann machines(RBMs)provided the best temperature prediction results(RMSE and R of the heating process are 0.9705℃and 0.9969,while the values of RMSE and R of the cooling process are 0.7866℃and 0.9977,respectively).The prediction results obtained by the optimal BPNN(five hidden layers,10 neurons in each layer,RMSE=1.1266℃,R=0.9957)were slightly inferior to those obtained by the DBN.The neural network could accurately and reliably predict the response of the HMF sensor in cycling operation,which provided the possibility for the flexible application of the complex MNF sensor in a wide sensing range.展开更多
In this paper, a novel antenna is proposed for high-temperature testing, which can make the high-temperature pressure characteristics of a wireless passive ceramic pressure sensor demonstrated at up to a temperature o...In this paper, a novel antenna is proposed for high-temperature testing, which can make the high-temperature pressure characteristics of a wireless passive ceramic pressure sensor demonstrated at up to a temperature of 600℃. The design parameters of the antenna are similar to those of the sensor, which will increase the coupling strength between the sensor and testing antenna. The antenna is fabricated in thick film integrated technology, and the properties of the alumina ceramic and silver ensure the feasibility of the antenna in high-temperature environments. The sensor, coupled with the ceramic antenna, is investigated using a high-temperature pressure testing platform. The experimental measurement results show that the pressure signal in a harsh environment can be detected by the frequency diversity of the sensor.展开更多
Biochemical reaction in microfluidic chip is sensitive to temperature.Temperature precise control in a small size device requires the temperature measurement with high measurement precision.Traditional temperature mea...Biochemical reaction in microfluidic chip is sensitive to temperature.Temperature precise control in a small size device requires the temperature measurement with high measurement precision.Traditional temperature measurement method usually measures the voltage drop of the thermistor,which is excited by a constant current source.This method requires the constant current source with high precision and stability.The output of the constant current source is influenced by environmental factors,resulting in a larger measurement error.To solve this problem,a proportion method,a two-layer filtering algorithm,and a power management technique were applied to improve the temperature measurement precision.The proportion method can reduce the low frequency fluctuation error.The two-layer filtering algorithm can reduce the high frequency fluctuation error furtherly.The power management technique used can improve the system stability.Through testing the temperature measurement system built,the experimental results show that the fluctuation error can be significantly decreased from 0.5◦C to 0.2◦C.展开更多
The femtosecond laser has been an efficient tool for optical fiber high temperature sensor construction.Here,we review the progress of optical fiber high temperature sensors based on femtosecond laser fabricated fiber...The femtosecond laser has been an efficient tool for optical fiber high temperature sensor construction.Here,we review the progress of optical fiber high temperature sensors based on femtosecond laser fabricated fiber gratings and various types of fiber in-line interferometers in silica fibers and sapphire fibers.展开更多
A fiber-optic temperature sensor based on fiber tip polystyrene microsphere is proposed.The sensor structure can be formed simply by placing and fixing a polystyrene microsphere on the center of an optical fiber tip.S...A fiber-optic temperature sensor based on fiber tip polystyrene microsphere is proposed.The sensor structure can be formed simply by placing and fixing a polystyrene microsphere on the center of an optical fiber tip.Since polystyrene has a much larger thermal expansivity,the structure can be used for high-sensitive temperature measurement.By the illuminating of the sensor with a broadband light source and through the optical Fabry-Perot interference between the front and back surfaces of the polystyrene microsphere,the optical phase difference(OPD)or wavelength shift can be used for the extraction of temperature.Temperature measurement experiment shows that,using a fiber probe polystyrene microsphere temperature sensor with a spherical diameter of about 91.7 pm,a high OPD-temperature sensitivity of about-0.61796nm/℃and a good linearity of 0.9916 were achieved in a temperature range of 20℃-70℃.展开更多
This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put ...This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.展开更多
This paper briefly introduces the characteristics of structure and optimum design of the hardware of the expert PID control system on temperature and humidity verifying box.Combined Microcontroller technology with exp...This paper briefly introduces the characteristics of structure and optimum design of the hardware of the expert PID control system on temperature and humidity verifying box.Combined Microcontroller technology with expert PID control technology and with regular construction of temperature-humidity expert control system,the paper sets up the expert control rules,as well as a subset of control flow.展开更多
Experimental Advanced Superconducting Tokamak(EAST) is the fully superconducting Tokamak.The EAST magnet system comprises 16 D-shaped toroidal field coils and 14 poloidal field coils which are cooled by supercritical ...Experimental Advanced Superconducting Tokamak(EAST) is the fully superconducting Tokamak.The EAST magnet system comprises 16 D-shaped toroidal field coils and 14 poloidal field coils which are cooled by supercritical helium at 4.2 K and 3.8 K.The temperature of superconducting coils is measured by Cernox as a new type low-temperature sensor,and monitored during the cooling and operation.The helium temperature can offer reference for quench signal.In this paper,a technique for the weak temperature signal measurement of superconducting coils is introduced,and its weak voltage is extracted from the intrinsic noise of the amplifier by the low-noise instrumentation amplifier,filter circuit,and high-linearity analog optocoupler.The temperature detection circuit works accurately and safely whether in cooling or operating process.This technique is an effective for the temperature detection on the low-temperature superconducting coils.展开更多
In view of domestic scientific and technological achievements at present,real-time control circuit for greenhouse temperature and light intensity has been designed in line with the principle of cost saving and easy co...In view of domestic scientific and technological achievements at present,real-time control circuit for greenhouse temperature and light intensity has been designed in line with the principle of cost saving and easy control.With advanced temperature sensor and light sensor applied to measure the temperature and light intensity,an execution unit is controlled by single-chip microcomputer(SCM)to regulate the temperature and light intensity,creating a hardware design scheme and software design idea.In case of high temperature and high light intensity in greenhouse,the sunshade net will be put down and the blower will be started automatically;in case of low temperature and light intensity,the sunshade net will be folded up and the heating valve will be turned up automatically.In this way,the temperature and light intensity in greenhouse will be controlled within the designed range.展开更多
基金National Natural Science Foundation of China(Nos.12002085 and 51603039)Shanghai Pujiang Program,China(No.19PJC002)+2 种基金Fundamental Research Funds for the Central Universities of ministry of Education of China(Nos.2232017D-12)Key Laboratory of Textile Science and Technology(Donghua University),Ministry of Education,China(No.KLTST201623)Initial Research Funds for Young Teachers of Donghua University,China(No.104-07-005388)。
文摘The development of wearable technologies promotes the research of flexible sensors.It is hoped that a flexible sensor can collect different physiological data,such as temperature and respiratory rate(RR).The temperature of the exhaled gas is generally higher than that in the air,and the periodic change of temperature is related to the respiratory rate.In this work,we use platinum fiber and spandex fiber to prepare yarn-based temperature sensor with high tensile performance through hollow spindle wrapping spinning technology.After the measurement,the sensitivity of the sensor can reach at least 3.18×10^(-3)℃^(-1).We use the sensor and ordinary fabric mask to prepare a sensor mask that can monitor human respiratory signals to explore the performance of the sensor in RR measurement.The experimental results show that when measuring human RR,the yarn-based temperature sensor can accurately distinguish different respiratory states such as normal breathing,deep breathing,and rapid breathing while speaking.It is suggested that yarn-based temperature sensors can be used in medical fields such as real-time respiratory detection and temperature measurement.
文摘This paper addresses some of the problems related to direct surface temperature measurement of a salient pole synchronous generator excitation winding in rotation. Excitation winding temperature is used for determining the dynamic limit in a PQ diagram. The paper also addresses procedures of improving the accuracy of surface temperature measurement using the contact DS 18B20 digital temperature probes. The paper also provides experimental results of direct temperature measurement of the excitation winding surface conducted in the salient pole synchronous generator in the rotation.
文摘The accuracy of temperature measurement is often reduced due to random noise in Raman-based distributed temperature sensor (RDTS). A noise reduction method based on a nonlinear filter is thus proposed in this paper. Compared with the temperature demodulation results of raw signals, the proposed method in this paper can reduce the average maximum deviation of temperature measurement results from 4.1°C to 1.2°C at 40.0°C, 50.0°C and 60.0°C. And the proposed method in this paper can improve the accuracy of temperature measurement of Raman-based distributed temperature sensor better than the commonly used wavelet transform-based method. The advantages of the proposed method in improving the accuracy of temperature measurement for Raman-based distributed temperature sensor are quantitatively reflected in the maximum deviation and root mean square error of temperature measurement results. Therefore, this paper proposes an effective and feasible method to improve the accuracy of temperature measurement results for Raman-based distributed temperature sensor.
基金Project supported by the Scientific Research Project of Institutions of Higher Learning in Inner Mongolia Autonomous Region,China(Grant No.NJZY19214)
文摘A highly sensitive optical fiber temperature sensor based on a section of liquid-filled silica capillary tube(SCT)between single mode fibers is proposed. Two micro-holes are drilled on two sides of SCT directly by using femtosecond laser micromachining, and liquid polymer is filled into the SCT through the micro-holes without any air bubbles and then sealed by using ultra-violet(UV) cure adhesive. The sidewall of the SCT forms a Fabry–Perot resonator, and loss peaks are achieved in the transmission spectrum of the SCT at the resonant wavelength. The resonance condition can be influenced by the refractive index variation of the liquid polymer filled in SCT, which is sensitive to temperature due to its high thermooptical coefficient(-2.98 × 10^-4℃^-1). The experimental result shows that the temperature sensitivity of the proposed fiber structure reaches 5.09 nm/℃ with a perfect linearity of 99.8%. In addition, it exhibits good repeatability and reliability in temperature sensing application.
文摘Dynamic capacity increase in high voltage electric power transmission line is currently the most economical method for solving electric power transmission bottleneck nowadays. DS18B20 temperature sensor is applied to the dynamic capacity increase of high voltage transmission lines to measure the conductor temperature and ambient temperature. The paper is focused on the experiment of DS18B20 both in the laboratory and outside. From the result of the lab temperature measurement data analysis, using 4 DS18B20’s is the most suitable plan, considering both accuracy and economical efficiency. In the experiment outside, we get four groups of conductor (uncharged) temperature and four groups of ambient temperature. The data proved that DS18B20 has good stability, and small measurement error. It is suitable for measuring the temperature of conductor and ambient in dynamic capacity increase, and helpful to improve the accuracy of the calculation of capacity increasing.
文摘A novel system configuration of fiber optic sensor based on optical abso rption is proposed. Several compensation measures are discussed. A simulated exp eriment is designed and the output curve of system is given. The experiment al result shows that these compensation measures are effective on dynamic distu rbances which are caused by background light and optical fiber bend. In addition , the drifts in the light source intensity, fiber losses, and photodetector effi ciency are also compensated.
文摘The principle of a new optical fiber temperature transducer is presented,and ingenious design scheme of this transducer is given.Because taking the special modulation and ratio measurement,this new transducer has provided with high characteristics:experimental transmitting distance is 500m;measurement error,in the measured temperature range of 0-250℃，,is less than ±0.5℃;power consumption of the probe is less than 300μW.Finally,some points of the experiment are given.
文摘Taking a specific production process as an example, this paper introduces the design of multi slot and unequal temperature PID controller based on single chip microcomputer. The mathematical implementation method of PID algorithm and the design method of the hardware and software are discussed, The principle diagram of the hardware circuit implementing the control algorithm and the features of the software possessed are also presented.
文摘The inconsistent response curve of delicate micro/nanofiber(MNF)sensors during cycling measurement is one of the main factors which greatly limit their practical application.In this paper,we proposed a temperature sensor based on the copper rod-supported helical microfiber(HMF).The HMF sensors exhibited different light intensity-temperature response relationships in single-cycle measurements.Two neural networks,the deep belief network(DBN)and the backpropagation neural network(BPNN),were employed respectively to predict the temperature of the HMF sensor in different sensing processes.The input variables of the network were the sensor geometric parameters(the microfiber diameter,wrapped length,coiled turns,and helical angle)and the output optical intensity under different working processes.The root mean square error(RMSE)and Pearson correlation coefficient(R)were used to evaluate the predictive ability of the networks.The DBN with two restricted Boltzmann machines(RBMs)provided the best temperature prediction results(RMSE and R of the heating process are 0.9705℃and 0.9969,while the values of RMSE and R of the cooling process are 0.7866℃and 0.9977,respectively).The prediction results obtained by the optimal BPNN(five hidden layers,10 neurons in each layer,RMSE=1.1266℃,R=0.9957)were slightly inferior to those obtained by the DBN.The neural network could accurately and reliably predict the response of the HMF sensor in cycling operation,which provided the possibility for the flexible application of the complex MNF sensor in a wide sensing range.
基金Project supported by the National Natural Science Foundation for Distinguished Young Scholars,China(Grant No.51425505)the National Natural Science Foundation of China(Grant No.61471324)+1 种基金the Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi Province,China(Grant No.2013-077)the Graduate Students Outstanding Innovation Project of Shanxi Province,China(Grant No.20143020)
文摘In this paper, a novel antenna is proposed for high-temperature testing, which can make the high-temperature pressure characteristics of a wireless passive ceramic pressure sensor demonstrated at up to a temperature of 600℃. The design parameters of the antenna are similar to those of the sensor, which will increase the coupling strength between the sensor and testing antenna. The antenna is fabricated in thick film integrated technology, and the properties of the alumina ceramic and silver ensure the feasibility of the antenna in high-temperature environments. The sensor, coupled with the ceramic antenna, is investigated using a high-temperature pressure testing platform. The experimental measurement results show that the pressure signal in a harsh environment can be detected by the frequency diversity of the sensor.
基金the Professional Technical Service Platform of Science and Technology Commission of Shanghai Municipality(No.19DZ2291103)。
文摘Biochemical reaction in microfluidic chip is sensitive to temperature.Temperature precise control in a small size device requires the temperature measurement with high measurement precision.Traditional temperature measurement method usually measures the voltage drop of the thermistor,which is excited by a constant current source.This method requires the constant current source with high precision and stability.The output of the constant current source is influenced by environmental factors,resulting in a larger measurement error.To solve this problem,a proportion method,a two-layer filtering algorithm,and a power management technique were applied to improve the temperature measurement precision.The proportion method can reduce the low frequency fluctuation error.The two-layer filtering algorithm can reduce the high frequency fluctuation error furtherly.The power management technique used can improve the system stability.Through testing the temperature measurement system built,the experimental results show that the fluctuation error can be significantly decreased from 0.5◦C to 0.2◦C.
基金supported by the National Natural Science Foundation of China (No. 61975192)
文摘The femtosecond laser has been an efficient tool for optical fiber high temperature sensor construction.Here,we review the progress of optical fiber high temperature sensors based on femtosecond laser fabricated fiber gratings and various types of fiber in-line interferometers in silica fibers and sapphire fibers.
基金This research was partially funded by Natural Science Basic Research Project of Shaanxi Province,China(Grant No.2020JM-560)Key Scientific Research Plan of Education Department of Shaanxi Province,China(Grant No.20JY028)the National Natural Science Foundation of China(Grant No.61704134).
文摘A fiber-optic temperature sensor based on fiber tip polystyrene microsphere is proposed.The sensor structure can be formed simply by placing and fixing a polystyrene microsphere on the center of an optical fiber tip.Since polystyrene has a much larger thermal expansivity,the structure can be used for high-sensitive temperature measurement.By the illuminating of the sensor with a broadband light source and through the optical Fabry-Perot interference between the front and back surfaces of the polystyrene microsphere,the optical phase difference(OPD)or wavelength shift can be used for the extraction of temperature.Temperature measurement experiment shows that,using a fiber probe polystyrene microsphere temperature sensor with a spherical diameter of about 91.7 pm,a high OPD-temperature sensitivity of about-0.61796nm/℃and a good linearity of 0.9916 were achieved in a temperature range of 20℃-70℃.
文摘This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.
文摘This paper briefly introduces the characteristics of structure and optimum design of the hardware of the expert PID control system on temperature and humidity verifying box.Combined Microcontroller technology with expert PID control technology and with regular construction of temperature-humidity expert control system,the paper sets up the expert control rules,as well as a subset of control flow.
基金Supported by the National Natural Science Foundation ofChina(No.11005126)
文摘Experimental Advanced Superconducting Tokamak(EAST) is the fully superconducting Tokamak.The EAST magnet system comprises 16 D-shaped toroidal field coils and 14 poloidal field coils which are cooled by supercritical helium at 4.2 K and 3.8 K.The temperature of superconducting coils is measured by Cernox as a new type low-temperature sensor,and monitored during the cooling and operation.The helium temperature can offer reference for quench signal.In this paper,a technique for the weak temperature signal measurement of superconducting coils is introduced,and its weak voltage is extracted from the intrinsic noise of the amplifier by the low-noise instrumentation amplifier,filter circuit,and high-linearity analog optocoupler.The temperature detection circuit works accurately and safely whether in cooling or operating process.This technique is an effective for the temperature detection on the low-temperature superconducting coils.
文摘In view of domestic scientific and technological achievements at present,real-time control circuit for greenhouse temperature and light intensity has been designed in line with the principle of cost saving and easy control.With advanced temperature sensor and light sensor applied to measure the temperature and light intensity,an execution unit is controlled by single-chip microcomputer(SCM)to regulate the temperature and light intensity,creating a hardware design scheme and software design idea.In case of high temperature and high light intensity in greenhouse,the sunshade net will be put down and the blower will be started automatically;in case of low temperature and light intensity,the sunshade net will be folded up and the heating valve will be turned up automatically.In this way,the temperature and light intensity in greenhouse will be controlled within the designed range.
