In the practical application of pneumatic control devices, the nonlinearity of a pneumatic control valve become the main factor affecting the control effect, which comes mainly from the dynamic friction force. The dyn...In the practical application of pneumatic control devices, the nonlinearity of a pneumatic control valve become the main factor affecting the control effect, which comes mainly from the dynamic friction force. The dynamic friction inside the valve may cause hysteresis and a dead zone. In this paper, a dither compensation mechanism is proposed to reduce negative effects on the basis of analyzing the mechanism of friction force. The specific dither signal（using a sinusoidal signal） was superimposed on the control signal of the valve. Based on the relationship between the parameters of the dither signal and the inherent characteristics of the proportional servo valve, a parameter tuning method was proposed, which uses a displacement sensor to measure the maximum static friction inside the valve. According to the experimental results, the proper amplitude ranges are determined for different pressures. In order to get the optimal parameters of the dither signal, some dither compensation experiments have been carried out on different signal amplitude and gas pressure conditions. Optimal parameters are determined under two kinds of pressure conditions. Using tuning parameters the valve spool displacement experiment has been taken. From the experiment results, hysteresis of the proportional servo valve is significantly reduced. And through simulation and experiments, the cut-off frequency of the proportional valve has also been widened. Therefore after adding the dither signal, the static and dynamic characteristics of the proportional valve are both improved to a certain degree. This research proposes a parameter tuning method of dither signal, and the validity of the method is verified experimentally.展开更多
Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance pr...Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance proportional coefficient. The NMR spectrometer used this investigation was a Bruker AM-500 spectrometer operating at 202.4 MHz for ^(31)P chemical shifts are relative to 85% phosphoric acid. TIC was carried out by silica gel H plate developed in chloroform-methanol-glacial acetic acid-ethanol-water(25:4:6:2:0.5),with Vaskovsky reagent as colour -developing agent of phospholipids.展开更多
Objective:To utilize the VigiAccess database for data mining to analyze the characteristics of adverse reactions induced by mirogabalin,providing critical information for clinical medication use.Method:This study anal...Objective:To utilize the VigiAccess database for data mining to analyze the characteristics of adverse reactions induced by mirogabalin,providing critical information for clinical medication use.Method:This study analyzed data from the VigiAccess database,filtering out adverse reaction reports where mirogabalin was identified as the Primary Suspect Drug(PS).Reporting Odds Ratio(ROR),Proportional Reporting Ratio(PRR),Bayesian Confidence Propagation Neural Network(BCPNN),and Empirical Bayes Geometric Mean(EBGM)methods were employed as data mining algorithms for pharmacovigilance and adverse event monitoring.These methods identify potential drug-adverse event association signals by analyzing the relationship between drug use and adverse event reporting.ROR and PRR focus on calculating reporting ratios,while BCPNN and EBGM use neural networks and empirical Bayes models,respectively,to enhance the accuracy and reliability of signal detection.Results:A total of 734 adverse reaction reports associated with mirogabalin were obtained.The results showed that females reported the highest number of adverse reactions,accounting for 59.67%,while males accounted for 38.83%.In terms of age distribution,the highest number of reports came from individuals over 75 years old,accounting for 33.79%.Adverse reactions mainly involved the nervous system(33.45%),general diseases and reactions at the site of administration(11.62%),and gastrointestinal disorders(10.74%).The most common adverse reactions included dizziness(11.62%),somnolence(8.27%),renal dysfunction(2.90%),and edema(2.82%).Signal intensity analysis revealed that certain adverse reactions(such as renal dysfunction,rhabdomyolysis,and drug-induced liver injury)had significant signal strength,suggesting a strong association with mirogabalin.Conclusion:This study,through signal mining of the VigiAccess database,reveals the characteristics of mirogabalin’s adverse reactions in the real world,particularly in the nervous system and renal function.These findings provide important reference information for clinicians,aiding in the optimization of the safe use of mirogabalin.Future research should further validate the causal relationships of these signals and explore individualized treatment strategies to reduce the incidence of adverse reactions and improve patient outcomes.展开更多
[Objective] The aim of this study was to evaluate the economic loss caused by Zhouqu debris flow. [Method] After the large debris flows happened on August 7, 2010 in Zhouqu, Gansu Province, we collected data at the fi...[Objective] The aim of this study was to evaluate the economic loss caused by Zhouqu debris flow. [Method] After the large debris flows happened on August 7, 2010 in Zhouqu, Gansu Province, we collected data at the first time after the disaster, and then built an assessment model to estimate the potential economic losses. [Result] The total loss reached 16.57×10^2 million Yuan, in which indirect economic loss was up to 2.42×10^2 million yaun while the actual direct economic loss was around 14.15×10^2 million Yuan. [Conclusion] The proportional coefficient method is a rapid and efficient method for evaluating the indirect loss caused by disasters.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
基金Supported by National Natural Science Foundation of China(Grant No.51375045)the State Key Laboratory Program(Grant No.GZKF-201214)
文摘In the practical application of pneumatic control devices, the nonlinearity of a pneumatic control valve become the main factor affecting the control effect, which comes mainly from the dynamic friction force. The dynamic friction inside the valve may cause hysteresis and a dead zone. In this paper, a dither compensation mechanism is proposed to reduce negative effects on the basis of analyzing the mechanism of friction force. The specific dither signal（using a sinusoidal signal） was superimposed on the control signal of the valve. Based on the relationship between the parameters of the dither signal and the inherent characteristics of the proportional servo valve, a parameter tuning method was proposed, which uses a displacement sensor to measure the maximum static friction inside the valve. According to the experimental results, the proper amplitude ranges are determined for different pressures. In order to get the optimal parameters of the dither signal, some dither compensation experiments have been carried out on different signal amplitude and gas pressure conditions. Optimal parameters are determined under two kinds of pressure conditions. Using tuning parameters the valve spool displacement experiment has been taken. From the experiment results, hysteresis of the proportional servo valve is significantly reduced. And through simulation and experiments, the cut-off frequency of the proportional valve has also been widened. Therefore after adding the dither signal, the static and dynamic characteristics of the proportional valve are both improved to a certain degree. This research proposes a parameter tuning method of dither signal, and the validity of the method is verified experimentally.
文摘Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance proportional coefficient. The NMR spectrometer used this investigation was a Bruker AM-500 spectrometer operating at 202.4 MHz for ^(31)P chemical shifts are relative to 85% phosphoric acid. TIC was carried out by silica gel H plate developed in chloroform-methanol-glacial acetic acid-ethanol-water(25:4:6:2:0.5),with Vaskovsky reagent as colour -developing agent of phospholipids.
基金Hubei Provincial Natural Science Foundation Innovation and Development Joint Fund Project(2025AFD278)Three Gorges University Scientific Fund Project(2022kj008)Three Gorges University Special Scientific Fund Project(2023kjzx001)。
文摘Objective:To utilize the VigiAccess database for data mining to analyze the characteristics of adverse reactions induced by mirogabalin,providing critical information for clinical medication use.Method:This study analyzed data from the VigiAccess database,filtering out adverse reaction reports where mirogabalin was identified as the Primary Suspect Drug(PS).Reporting Odds Ratio(ROR),Proportional Reporting Ratio(PRR),Bayesian Confidence Propagation Neural Network(BCPNN),and Empirical Bayes Geometric Mean(EBGM)methods were employed as data mining algorithms for pharmacovigilance and adverse event monitoring.These methods identify potential drug-adverse event association signals by analyzing the relationship between drug use and adverse event reporting.ROR and PRR focus on calculating reporting ratios,while BCPNN and EBGM use neural networks and empirical Bayes models,respectively,to enhance the accuracy and reliability of signal detection.Results:A total of 734 adverse reaction reports associated with mirogabalin were obtained.The results showed that females reported the highest number of adverse reactions,accounting for 59.67%,while males accounted for 38.83%.In terms of age distribution,the highest number of reports came from individuals over 75 years old,accounting for 33.79%.Adverse reactions mainly involved the nervous system(33.45%),general diseases and reactions at the site of administration(11.62%),and gastrointestinal disorders(10.74%).The most common adverse reactions included dizziness(11.62%),somnolence(8.27%),renal dysfunction(2.90%),and edema(2.82%).Signal intensity analysis revealed that certain adverse reactions(such as renal dysfunction,rhabdomyolysis,and drug-induced liver injury)had significant signal strength,suggesting a strong association with mirogabalin.Conclusion:This study,through signal mining of the VigiAccess database,reveals the characteristics of mirogabalin’s adverse reactions in the real world,particularly in the nervous system and renal function.These findings provide important reference information for clinicians,aiding in the optimization of the safe use of mirogabalin.Future research should further validate the causal relationships of these signals and explore individualized treatment strategies to reduce the incidence of adverse reactions and improve patient outcomes.
基金Supported by National Key Technology Research and Development Program(2008BAK50B06)~~
文摘[Objective] The aim of this study was to evaluate the economic loss caused by Zhouqu debris flow. [Method] After the large debris flows happened on August 7, 2010 in Zhouqu, Gansu Province, we collected data at the first time after the disaster, and then built an assessment model to estimate the potential economic losses. [Result] The total loss reached 16.57×10^2 million Yuan, in which indirect economic loss was up to 2.42×10^2 million yaun while the actual direct economic loss was around 14.15×10^2 million Yuan. [Conclusion] The proportional coefficient method is a rapid and efficient method for evaluating the indirect loss caused by disasters.
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.
