A physical retrieval approach based on the one-dimensional variational(1 D-Var) algorithm is applied in this paper to simultaneously retrieve atmospheric temperature and humidity profiles under both clear-sky and part...A physical retrieval approach based on the one-dimensional variational(1 D-Var) algorithm is applied in this paper to simultaneously retrieve atmospheric temperature and humidity profiles under both clear-sky and partly cloudy conditions from FY-4 A GIIRS(geostationary interferometric infrared sounder) observations. Radiosonde observations from upper-air stations in China and level-2 operational products from the Chinese National Satellite Meteorological Center(NSMC)during the periods from December 2019 to January 2020(winter) and from July 2020 to August 2020(summer) are used to validate the accuracies of the retrieved temperature and humidity profiles. Comparing the 1 D-Var-retrieved profiles to radiosonde data, the accuracy of the temperature retrievals at each vertical level of the troposphere is characterized by a root mean square error(RMSE) within 2 K, except for at the bottom level of the atmosphere under clear conditions. The RMSE increases slightly for the higher atmospheric layers, owing to the lack of temperature sounding channels there.Under partly cloudy conditions, the temperature at each vertical level can be obtained, while the level-2 operational products obtain values only at altitudes above the cloud top. In addition, the accuracy of the retrieved temperature profiles is greatly improved compared with the accuracies of the operational products. For the humidity retrievals, the mean RMSEs in the troposphere in winter and summer are both within 2 g kg^(–1). Moreover, the retrievals performed better compared with the ERA5 reanalysis data between 800 h Pa and 300 h Pa both in summer and winter in terms of RMSE.展开更多
One-dimensional retrieval was performed on Typhoon Haiyan utilizing the advanced technology microwave sounder onboard the satellite Suomi NPP to retrieve the temperature and water vapor profiles of the typhoon.Compari...One-dimensional retrieval was performed on Typhoon Haiyan utilizing the advanced technology microwave sounder onboard the satellite Suomi NPP to retrieve the temperature and water vapor profiles of the typhoon.Comparisons of the retrieved profiles and ECMWF reanalysis were made to assess the results. The main conclusions are as follows.(1) The results have high spatial resolution and therefore can precisely represent the temperature and humidity distribution of the typhoon.(2) The retrieved temperature is low in the areas of low temperature and high in the areas of high temperature; similar patterns are observed for humidity. This means that systematic revision may be needed during routine application.(3) The results of the retrieved temperature and humidity profiles are generally accurate, which is quite important for typhoon monitoring.展开更多
Evapotranspiration in forests has been researched for a long time because it serves an important role in water resource issues and biomass production. By applying the reciprocal analysis based on the Bowen ratio conce...Evapotranspiration in forests has been researched for a long time because it serves an important role in water resource issues and biomass production. By applying the reciprocal analysis based on the Bowen ratio concept to the canopy surface, the sum result of sensible and latent heat fluxes, i.e., actual evapotranspiration (ET), is estimated from engineering aspect using the net radiation (Rn) and heat flux into the ground (G). The new method uses air temperature and humidity at a single height by determining the relative humidity (rehs) using the canopy temperature (Ts). The validity of the method is confirmed by the latent heat flux (lE) and sensible heat flux (H) observed by mean of eddy covariance method. The heat imbalance is corrected by multiple regression analysis. The temporal change of lE and H at the canopy surface is clarified using hourly and yearly data. Furthermore, the observed and estimated monthly evapotranspiration of the sites are compared. The research is conducted using hourly data and the validation of the method is conducted using observed covariance at five sites in the world using FLUXNET.展开更多
The experiment was mainly used to study the effect of insect-proof net mulching cultivation technology on the temperature and humidity of the greenhouse and the spring shoot growth of citrus Shatangju. The results sho...The experiment was mainly used to study the effect of insect-proof net mulching cultivation technology on the temperature and humidity of the greenhouse and the spring shoot growth of citrus Shatangju. The results showed that the 40-mesh translucent insect-proof net had a positive effect on the spring shoot growth of Shatangju in the spring from January to April. In the meantime,according to the change of the temperature and humidity inside and outside the insect-proof net and the change of quantity of Aleyrodidae,Tetranychidae and Phyllocnisidae,it was found that the role of insect-proof net in enhancing the spring shoot growth of Shatangju was possibly achieved by the regulation of citrus pests and the temperature and humidity inside the net.展开更多
Objective: To explore the application of intelligent blood temperature and humidity monitoring system in cold chain management of blood station. Methods: Through the monitoring of fifty sets of cold-chain equipment in...Objective: To explore the application of intelligent blood temperature and humidity monitoring system in cold chain management of blood station. Methods: Through the monitoring of fifty sets of cold-chain equipment in the central blood station in Hezhou for 6 months, the differences between the management of the automatic temperature and humidity monitoring system and the manual management were compared in terms of real-time recording, equipment alarm, data storage, historical data traceability and data analysis. Results: Temperature and humidity automatic monitoring system can automatically real-time acquisition, transmission, storage and alarm according to the required time interval;meanwhile, historical data can be quickly exported and traced, data and charts can be analyzed, and the alarm is real-time and effective. Conclusion: The system can effectively monitor the process of blood cold chain in blood stations and play a key role in ensuring blood quality. It can be popularized and used in blood stations.展开更多
Full-length grouted bolts play a crucial role in geotechnical engineering thanks to their excellent stability.However,few studies have been concerned with the degrading performance of grouted rock bolts caused by exte...Full-length grouted bolts play a crucial role in geotechnical engineering thanks to their excellent stability.However,few studies have been concerned with the degrading performance of grouted rock bolts caused by extensive and continuous heat conduction from surrounding rocks in high-geothermal tunnels buried more than 100 m(temperature from 28C to 100C).To investigate the damage mechanism,we examined the time-varying behaviors of grouted rock bolts in both constant and variable temperature curing environments and their damage due to the coupling effects of high temperature and humidity through mechanical and micro-feature tests,including uniaxial compression test,pull-out test,computed tomography(CT)scans,X-ray diffraction(XRD)test,thermogravimetric analysis(TGA),etc.,and further analyzed the relationship between grout properties and anchorage capability.In order to facilitate a rapid assessment and control of the anchorage performance of anchors in different conditions,results of the interface bond degradation tests were correlated to environment parameters based on the damage model of interfacial bond stress proposed.Accordingly,a thermal hazard classification criterion for anchorage design in high-geothermal tunnels was suggested.Based on the reported results,although high temperature accelerated the early-stage hydration reaction of grouting materials,it affected the distribution and quantity of hydration products by inhibiting hydration degree,thus causing mechanical damage to the anchorage system.There was a significant positive correlation between the strength of the grouting material and the anchoring force.Influenced by the changes in grout properties,three failure patterns of rock bolts typically existed.Applying a hot-wet curing regime results in less reduction in anchorage force compared to the hot-dry curing conditions.The findings of this study would contribute to the design and investigations of grouted rock bolts in high-geothermal tunnels.展开更多
Aiming at the actual demand for monitoring environmental information,a wireless sensing system for temperature and relative humidity(RH)monitoring based on radio frequency(RF)technology and mobile network was designed...Aiming at the actual demand for monitoring environmental information,a wireless sensing system for temperature and relative humidity(RH)monitoring based on radio frequency(RF)technology and mobile network was designed.This paper introduces the architecture of the system.The system uses AVR micro controller unit(MCU),KYL-1020U RF module and SHT71 to complete real-time temperature and humidity monitoring,and uses SIM900A module to realize remote alarming and monitoring with short message system(SMS)through global system for mobile communication(GSM).Experimental results show that the designed system has good stability of measurement and real-time performance,and it can be used in some small temperature and humidity monitoring occasions.展开更多
Ensuring safety in the use of medical equipment is an important guarantee for clinical diagnosis and treatment.Because medical equipment is mostly electrical and electronic equipment,the suddenness of its failure is i...Ensuring safety in the use of medical equipment is an important guarantee for clinical diagnosis and treatment.Because medical equipment is mostly electrical and electronic equipment,the suddenness of its failure is inevitable.Although some equipment has regular preventive maintenance and metrological calibration,it is patient-free static calibrated.In China,because of its large population,large patient base,and large use of medical equipment,nurses are too busy taking care of patients and cannot pay attention to the safety of the use of each device.Therefore,we propose using the Internet of Things and IT technology to carry out real-time monitoring and alarming of important parameters of some special,high-risk,and large-used medical equipment,so as to strengthen the safety management of equipment use.Through the management innovation,this article successfully implemented real-time monitoring of the temperature and humidity of the neonatal incubator;and greatly improved the safety in the use of such equipment.展开更多
Temperature and humidity independent control(THIC)air-conditioning system is a promising technology.In this work,a novel temperature and humidity independent control(THIC)system is proposed,namely VMD-ACERS,which inte...Temperature and humidity independent control(THIC)air-conditioning system is a promising technology.In this work,a novel temperature and humidity independent control(THIC)system is proposed,namely VMD-ACERS,which integrates vacuum membrane-based dehumidification and air carrying energy radiant air-conditioning system.This work establishes a novel coefficient of performance(COP)model of VMD-ACERS.The main parameters affecting the COP of conventional fan coil unit cooling system(FCUCS)and VMD-ACERS are investigated.The performance of FCUCS and VMD-ACERS are compared,and the energy-saving potential of VMD-ACERS is proved.Results indicate that,for FCUCS,the importance ranking of parameters is basically stable.However,for VMD-ACERS,the importance ranking will be affected by FCU and refrigerant.The most important parameters of VMD-ACERS are condensation temperature and permeate side pressure.On the contrary,superheating,subcooling are relatively less important parameters.For VMD-ACERS,it is not necessary to pursue the membrane with very high selectivity,because the selectivity of membrane would also be a less important parameter when it reaches 500.The COP of VMD-ACERS is higher than that of FCUCS when the permeate side pressure is higher than 8 k Pa.The VMD-ACERS solves two technical problems about power-saving and thermal comfort of conventional THIC,and can extend the application of THIC air-conditioning system.展开更多
Evapotranspiration acts an important role in hydrologic cycle and water resources planning. But the estimation issue still remains until nowadays. This research attempts to make clear this problem by the following way...Evapotranspiration acts an important role in hydrologic cycle and water resources planning. But the estimation issue still remains until nowadays. This research attempts to make clear this problem by the following way. In a humid region, by applying the Bowen ratio concept and optimum procedure on the soil surface, sensible and latent heat fluxes are estimated using net radiation (Rn) and heat flux into the ground (G). The method uses air temperature and humidity at a single height by reciprocally determining the soil surface temperature (Ts) and the relative humidity (rehs). This feature can be remarkably extended to the utilization. The validity of the method is confirmed by comparing of observed and estimated latent (lE) and sensible heat flux (H) using the eddy covariance method. The hourly change of the lE, H, Ts and rehs on the soil surface, yearly change of lE and H and relationship of estimated lE and H versus observed are clarified. Furthermore, monthly evapotranspiration is estimated from the lE. The research was conducted using hourly data of FLUXNET at a site of Japan, three sites of the United States and two sites of Europe in humid regions having over 1000 mm of annual precipitation.展开更多
Sorbitol,triethanolamine,sodium benzoate,boric acid,and sodium carbonate were mixed to prepare a waterborne rust inhibitor.A temperature and humidity accelerated corrosion test was applied to investigate the corrosion...Sorbitol,triethanolamine,sodium benzoate,boric acid,and sodium carbonate were mixed to prepare a waterborne rust inhibitor.A temperature and humidity accelerated corrosion test was applied to investigate the corrosion behaviour of waterborne rust inhibitor coated Q235 steel and original Q235 steel,which was carried out in a temperature and humidity test chamber(WSHW-1000)at a temperature of 80℃and humidity of 95%.Compared with the original Q235,waterborne rust inhibitor coated Q235 has better resistance to corrosion in hot and humid ambient conditions.Electrochemical impedance spectroscopy and potentiodynamic polarization were measured with a three-electrode cell in 3.5%NaCl aqueous solution on a CHI760E potentiostat/galvanostat.Molecular dynamics was simulated to verify the synergistic corrosion inhibitory mechanism of sodium carbonate and triethanolamine.The test shows that the prepared waterborne rust inhibitor can reduce the tendency of Q235 to corrosion and can also effectively reduce the corrosion rate.展开更多
Aiming at the problem of greenhouse environmental information collection in agricultural production,this paper designs a greenhouse monitoring system based on STM32 microcontroller.The system uses STM32F103 series MCU...Aiming at the problem of greenhouse environmental information collection in agricultural production,this paper designs a greenhouse monitoring system based on STM32 microcontroller.The system uses STM32F103 series MCU as the main control unit,which is used to receive the detection results of the sensor.The host computer software displays and processes the monitoring data.The temperature and humidity sensors monitor air temperature and humidity.The capacitive soil moisture detection sensor monitors soil moisture.The carbon dioxide sensor monitors the concentration of carbon dioxide.The photosensitive sensor monitors light intensity.This design has low hardware cost and high data acquisition accuracy,which can be applied to the actual greenhouse agricultural production and has wide practicability.展开更多
Basing on some researchers' experimental results,the droplet impinging wall model was modified,and We Number and K Number were adopted to determine the mode of droplet impinging wall.The simulation results indicat...Basing on some researchers' experimental results,the droplet impinging wall model was modified,and We Number and K Number were adopted to determine the mode of droplet impinging wall.The simulation results indicated that the mode of impinging droplet is sticking on the wall in Muti-spout bed.The droplet impinging wall model modified can describe the droplet impinging wall phenomenon accurately in the multistage spouted fluidized flue gas desulfurization reactor.Basing on the study above,the distributions of temperature and relative humidity in the reactor were attained.In atomization region,the distribution of temperature exhibits "M" shape.The relative humidity exhibits"W"shape.The mass concentration of droplet reduces along axis of the reactor.Due to the multi-spouted configuration,droplet concentration increases obviously in the intersection region between the 1st and 2nd stage reaction region.The evaporating intensity reaches its peak value in the area of 200 mm away from the sprayer,and droplets are completely evaporated at 1500 mm.展开更多
As a typical physical retrieval algorithm for retrieving atmospheric parameters,one-dimensional variational(1 DVAR)algorithm is widely used in various climate and meteorological communities and enjoys an important pos...As a typical physical retrieval algorithm for retrieving atmospheric parameters,one-dimensional variational(1 DVAR)algorithm is widely used in various climate and meteorological communities and enjoys an important position in the field of microwave remote sensing.Among algorithm parameters affecting the performance of the 1 DVAR algorithm,the accuracy of the microwave radiative transfer model for calculating the simulated brightness temperature is the fundamental constraint on the retrieval accuracies of the 1 DVAR algorithm for retrieving atmospheric parameters.In this study,a deep neural network(DNN)is used to describe the nonlinear relationship between atmospheric parameters and satellite-based microwave radiometer observations,and a DNN-based radiative transfer model is developed and applied to the 1 DVAR algorithm to carry out retrieval experiments of the atmospheric temperature and humidity profiles.The retrieval results of the temperature and humidity profiles from the Microwave Humidity and Temperature Sounder(MWHTS)onboard the Feng-Yun-3(FY-3)satellite show that the DNN-based radiative transfer model can obtain higher accuracy for simulating MWHTS observations than that of the operational radiative transfer model RTTOV,and also enables the 1 DVAR algorithm to obtain higher retrieval accuracies of the temperature and humidity profiles.In this study,the DNN-based radiative transfer model applied to the 1 DVAR algorithm can fundamentally improve the retrieval accuracies of atmospheric parameters,which may provide important reference for various applied studies in atmospheric sciences.展开更多
Based on the climate observation data of Kangding City in recent 60 years,the changing trends of temperature and humidity index and wind efficiency index in Kangding City are analyzed.The results show that the annual ...Based on the climate observation data of Kangding City in recent 60 years,the changing trends of temperature and humidity index and wind efficiency index in Kangding City are analyzed.The results show that the annual average temperature and humidity index and wind efficiency index of Kangding in recent 60 years showed an upward trend,which is consistent with global warming climate.Temperature and humidity index tended to change from the cold grade to the relatively cold and cool grades,and wind efficiency index changed from the slightly cold wind grade to the cool wind grade.Seen from temperature and humidity index and wind efficiency index,the climate was comfortable and relatively comfortable from May to September,which will become an important climatic reference to attract tourists.展开更多
In order to facilitate the determination of the calendar life of mechanical parts,the author summarized his relevant research papers that had studied for many years as eight distinct topics:(A).The principle and metho...In order to facilitate the determination of the calendar life of mechanical parts,the author summarized his relevant research papers that had studied for many years as eight distinct topics:(A).The principle and method for compiling the equal-damage temperature and humidity spectrum;(B).The principle for preparing the high concentration medium solution;(C).The principle and method for determining the metal calendar life;(D).The principle and method for determining the protective coating calendar life;(E).The principle and method for determining the total calendar life;(F).The principle of the reliability processing;(G).The principle and method for determining the corrosion damage tolerance;(H).The principle and matching design method to ensure that the total fatigue life and the total calendar life of the mechanical part were safe simultaneously.The above contents established a complete set of theoretical systems and methods for determining the calendar life.展开更多
Traditional condensing air-conditioning systems consume large amounts of energy in hot and humid areas,and it is difficult to achieve simultaneous control of temperature and humidity.A combined absorption refrigeratio...Traditional condensing air-conditioning systems consume large amounts of energy in hot and humid areas,and it is difficult to achieve simultaneous control of temperature and humidity.A combined absorption refrigeration(AR)and liquid desiccant dehumidification(LDD)air-conditioning system based on cascade utilization of low-grade heat source is proposed.The system can realize independent control of temperature and humidity and carry out profound recovery of low-grade heat sources.Under the design conditions,the heat utilization rate C reaches 21.05%,which is 2.73 times that of the conventional absorption refrigeration reference system.A parametric sensitivity analysis is performed to optimize the system.The C increases from 9.79%to 18.55%and the coefficient of performance C O P t increases from 0.33 to 0.35 with an increase in chilled water temperature from 7°C to 15°C.With an increase in regenerant solution temperature from 60°C to 70°C,the C achieves the optimal value of 21.05%at 68°C.C decreases from 21.05%to 15.05%as the concentration of the regenerant solution increases from 36%to 40%.Under variable environmental temperature and humidity,the C the proposed system changes within a small range and stays much higher than that of the reference system with the same quality heat source,which indicates that the proposed system has a better adaptability to changing environmental parameters.展开更多
The green vegetation fraction(GVF)can greatly influence the partitioning of surface sensible and latent heat fluxes in numerical weather prediction(NWP)models.However,the multiyear averaged monthly GVF climatology—th...The green vegetation fraction(GVF)can greatly influence the partitioning of surface sensible and latent heat fluxes in numerical weather prediction(NWP)models.However,the multiyear averaged monthly GVF climatology—the most commonly used representation of the vegetation state in models—cannot capture the real-time vegetation state well.In this study,a near real-time(NRT)GVF dataset generated from an 8-day composite of the normalized difference vegetation index is compared with the 10-yr averaged monthly GVF provided by the WRF model.The annual variability of the GVF over North China is examined in detail.Many differences between the two GVF datasets are found over dryland,grassland,and cropland/grassland mosaic areas.Two experiments using different GVF datasets are performed to assess the impacts of GVF on forecasts of screen-level temperature and humidity.The results show that using NRT GVF can lead to a widespread reduction of 2-m temperature forecast errors from April to October.Evaluation against in-situ observations shows that the positive impact on 2-m temperature forecasts in the morning is more distinct than that in the afternoon.Our study demonstrates that NRT GVF can provide a more realistic representation of the vegetation state,which in turn helps to improve short-range forecasts in arid and semiarid regions of North China.Moreover,our study shows that the negative effect of using NRT GVF is closely related to the initial soil moisture.展开更多
基金supported in part by the National Key Research and Development Program of China under Grant No.2018YFC1507302in part by the National Natural Science Foundation of China under Grant No.41975028。
文摘A physical retrieval approach based on the one-dimensional variational(1 D-Var) algorithm is applied in this paper to simultaneously retrieve atmospheric temperature and humidity profiles under both clear-sky and partly cloudy conditions from FY-4 A GIIRS(geostationary interferometric infrared sounder) observations. Radiosonde observations from upper-air stations in China and level-2 operational products from the Chinese National Satellite Meteorological Center(NSMC)during the periods from December 2019 to January 2020(winter) and from July 2020 to August 2020(summer) are used to validate the accuracies of the retrieved temperature and humidity profiles. Comparing the 1 D-Var-retrieved profiles to radiosonde data, the accuracy of the temperature retrievals at each vertical level of the troposphere is characterized by a root mean square error(RMSE) within 2 K, except for at the bottom level of the atmosphere under clear conditions. The RMSE increases slightly for the higher atmospheric layers, owing to the lack of temperature sounding channels there.Under partly cloudy conditions, the temperature at each vertical level can be obtained, while the level-2 operational products obtain values only at altitudes above the cloud top. In addition, the accuracy of the retrieved temperature profiles is greatly improved compared with the accuracies of the operational products. For the humidity retrievals, the mean RMSEs in the troposphere in winter and summer are both within 2 g kg^(–1). Moreover, the retrievals performed better compared with the ERA5 reanalysis data between 800 h Pa and 300 h Pa both in summer and winter in terms of RMSE.
基金National Natural Science Foundation of China(91215302,51278308)Open Project for State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry,Institute of Atmospheric Physics(LAPC)
文摘One-dimensional retrieval was performed on Typhoon Haiyan utilizing the advanced technology microwave sounder onboard the satellite Suomi NPP to retrieve the temperature and water vapor profiles of the typhoon.Comparisons of the retrieved profiles and ECMWF reanalysis were made to assess the results. The main conclusions are as follows.(1) The results have high spatial resolution and therefore can precisely represent the temperature and humidity distribution of the typhoon.(2) The retrieved temperature is low in the areas of low temperature and high in the areas of high temperature; similar patterns are observed for humidity. This means that systematic revision may be needed during routine application.(3) The results of the retrieved temperature and humidity profiles are generally accurate, which is quite important for typhoon monitoring.
文摘Evapotranspiration in forests has been researched for a long time because it serves an important role in water resource issues and biomass production. By applying the reciprocal analysis based on the Bowen ratio concept to the canopy surface, the sum result of sensible and latent heat fluxes, i.e., actual evapotranspiration (ET), is estimated from engineering aspect using the net radiation (Rn) and heat flux into the ground (G). The new method uses air temperature and humidity at a single height by determining the relative humidity (rehs) using the canopy temperature (Ts). The validity of the method is confirmed by the latent heat flux (lE) and sensible heat flux (H) observed by mean of eddy covariance method. The heat imbalance is corrected by multiple regression analysis. The temporal change of lE and H at the canopy surface is clarified using hourly and yearly data. Furthermore, the observed and estimated monthly evapotranspiration of the sites are compared. The research is conducted using hourly data and the validation of the method is conducted using observed covariance at five sites in the world using FLUXNET.
基金Supported by Special Construction Project of Modern Agriculture(Citrus)Industry Technology System(cars-27)
文摘The experiment was mainly used to study the effect of insect-proof net mulching cultivation technology on the temperature and humidity of the greenhouse and the spring shoot growth of citrus Shatangju. The results showed that the 40-mesh translucent insect-proof net had a positive effect on the spring shoot growth of Shatangju in the spring from January to April. In the meantime,according to the change of the temperature and humidity inside and outside the insect-proof net and the change of quantity of Aleyrodidae,Tetranychidae and Phyllocnisidae,it was found that the role of insect-proof net in enhancing the spring shoot growth of Shatangju was possibly achieved by the regulation of citrus pests and the temperature and humidity inside the net.
文摘Objective: To explore the application of intelligent blood temperature and humidity monitoring system in cold chain management of blood station. Methods: Through the monitoring of fifty sets of cold-chain equipment in the central blood station in Hezhou for 6 months, the differences between the management of the automatic temperature and humidity monitoring system and the manual management were compared in terms of real-time recording, equipment alarm, data storage, historical data traceability and data analysis. Results: Temperature and humidity automatic monitoring system can automatically real-time acquisition, transmission, storage and alarm according to the required time interval;meanwhile, historical data can be quickly exported and traced, data and charts can be analyzed, and the alarm is real-time and effective. Conclusion: The system can effectively monitor the process of blood cold chain in blood stations and play a key role in ensuring blood quality. It can be popularized and used in blood stations.
基金support from the National Natural Science Foundation of China(Grant No.52208387)Open Fund of Key Laboratory of Geohazard Prevention of Hilly Mountains,Ministry of Land and Resources,China(Fujian Key Laboratory of Geohazard Prevention)(Grant No.FJKLGH2022K001).
文摘Full-length grouted bolts play a crucial role in geotechnical engineering thanks to their excellent stability.However,few studies have been concerned with the degrading performance of grouted rock bolts caused by extensive and continuous heat conduction from surrounding rocks in high-geothermal tunnels buried more than 100 m(temperature from 28C to 100C).To investigate the damage mechanism,we examined the time-varying behaviors of grouted rock bolts in both constant and variable temperature curing environments and their damage due to the coupling effects of high temperature and humidity through mechanical and micro-feature tests,including uniaxial compression test,pull-out test,computed tomography(CT)scans,X-ray diffraction(XRD)test,thermogravimetric analysis(TGA),etc.,and further analyzed the relationship between grout properties and anchorage capability.In order to facilitate a rapid assessment and control of the anchorage performance of anchors in different conditions,results of the interface bond degradation tests were correlated to environment parameters based on the damage model of interfacial bond stress proposed.Accordingly,a thermal hazard classification criterion for anchorage design in high-geothermal tunnels was suggested.Based on the reported results,although high temperature accelerated the early-stage hydration reaction of grouting materials,it affected the distribution and quantity of hydration products by inhibiting hydration degree,thus causing mechanical damage to the anchorage system.There was a significant positive correlation between the strength of the grouting material and the anchoring force.Influenced by the changes in grout properties,three failure patterns of rock bolts typically existed.Applying a hot-wet curing regime results in less reduction in anchorage force compared to the hot-dry curing conditions.The findings of this study would contribute to the design and investigations of grouted rock bolts in high-geothermal tunnels.
文摘Aiming at the actual demand for monitoring environmental information,a wireless sensing system for temperature and relative humidity(RH)monitoring based on radio frequency(RF)technology and mobile network was designed.This paper introduces the architecture of the system.The system uses AVR micro controller unit(MCU),KYL-1020U RF module and SHT71 to complete real-time temperature and humidity monitoring,and uses SIM900A module to realize remote alarming and monitoring with short message system(SMS)through global system for mobile communication(GSM).Experimental results show that the designed system has good stability of measurement and real-time performance,and it can be used in some small temperature and humidity monitoring occasions.
文摘Ensuring safety in the use of medical equipment is an important guarantee for clinical diagnosis and treatment.Because medical equipment is mostly electrical and electronic equipment,the suddenness of its failure is inevitable.Although some equipment has regular preventive maintenance and metrological calibration,it is patient-free static calibrated.In China,because of its large population,large patient base,and large use of medical equipment,nurses are too busy taking care of patients and cannot pay attention to the safety of the use of each device.Therefore,we propose using the Internet of Things and IT technology to carry out real-time monitoring and alarming of important parameters of some special,high-risk,and large-used medical equipment,so as to strengthen the safety management of equipment use.Through the management innovation,this article successfully implemented real-time monitoring of the temperature and humidity of the neonatal incubator;and greatly improved the safety in the use of such equipment.
基金The National Key Technology Support Program(2015BAJ03B01)the Hunan Provincial Innovation Foundation for Postgraduate Studies(CX20190287)。
文摘Temperature and humidity independent control(THIC)air-conditioning system is a promising technology.In this work,a novel temperature and humidity independent control(THIC)system is proposed,namely VMD-ACERS,which integrates vacuum membrane-based dehumidification and air carrying energy radiant air-conditioning system.This work establishes a novel coefficient of performance(COP)model of VMD-ACERS.The main parameters affecting the COP of conventional fan coil unit cooling system(FCUCS)and VMD-ACERS are investigated.The performance of FCUCS and VMD-ACERS are compared,and the energy-saving potential of VMD-ACERS is proved.Results indicate that,for FCUCS,the importance ranking of parameters is basically stable.However,for VMD-ACERS,the importance ranking will be affected by FCU and refrigerant.The most important parameters of VMD-ACERS are condensation temperature and permeate side pressure.On the contrary,superheating,subcooling are relatively less important parameters.For VMD-ACERS,it is not necessary to pursue the membrane with very high selectivity,because the selectivity of membrane would also be a less important parameter when it reaches 500.The COP of VMD-ACERS is higher than that of FCUCS when the permeate side pressure is higher than 8 k Pa.The VMD-ACERS solves two technical problems about power-saving and thermal comfort of conventional THIC,and can extend the application of THIC air-conditioning system.
文摘Evapotranspiration acts an important role in hydrologic cycle and water resources planning. But the estimation issue still remains until nowadays. This research attempts to make clear this problem by the following way. In a humid region, by applying the Bowen ratio concept and optimum procedure on the soil surface, sensible and latent heat fluxes are estimated using net radiation (Rn) and heat flux into the ground (G). The method uses air temperature and humidity at a single height by reciprocally determining the soil surface temperature (Ts) and the relative humidity (rehs). This feature can be remarkably extended to the utilization. The validity of the method is confirmed by comparing of observed and estimated latent (lE) and sensible heat flux (H) using the eddy covariance method. The hourly change of the lE, H, Ts and rehs on the soil surface, yearly change of lE and H and relationship of estimated lE and H versus observed are clarified. Furthermore, monthly evapotranspiration is estimated from the lE. The research was conducted using hourly data of FLUXNET at a site of Japan, three sites of the United States and two sites of Europe in humid regions having over 1000 mm of annual precipitation.
基金Funded by Key Scientific Research Projects Plan of Henan Higher Education Institutions(No.19A460025)National Natural Science Foundation of China(No.51809127)。
文摘Sorbitol,triethanolamine,sodium benzoate,boric acid,and sodium carbonate were mixed to prepare a waterborne rust inhibitor.A temperature and humidity accelerated corrosion test was applied to investigate the corrosion behaviour of waterborne rust inhibitor coated Q235 steel and original Q235 steel,which was carried out in a temperature and humidity test chamber(WSHW-1000)at a temperature of 80℃and humidity of 95%.Compared with the original Q235,waterborne rust inhibitor coated Q235 has better resistance to corrosion in hot and humid ambient conditions.Electrochemical impedance spectroscopy and potentiodynamic polarization were measured with a three-electrode cell in 3.5%NaCl aqueous solution on a CHI760E potentiostat/galvanostat.Molecular dynamics was simulated to verify the synergistic corrosion inhibitory mechanism of sodium carbonate and triethanolamine.The test shows that the prepared waterborne rust inhibitor can reduce the tendency of Q235 to corrosion and can also effectively reduce the corrosion rate.
文摘Aiming at the problem of greenhouse environmental information collection in agricultural production,this paper designs a greenhouse monitoring system based on STM32 microcontroller.The system uses STM32F103 series MCU as the main control unit,which is used to receive the detection results of the sensor.The host computer software displays and processes the monitoring data.The temperature and humidity sensors monitor air temperature and humidity.The capacitive soil moisture detection sensor monitors soil moisture.The carbon dioxide sensor monitors the concentration of carbon dioxide.The photosensitive sensor monitors light intensity.This design has low hardware cost and high data acquisition accuracy,which can be applied to the actual greenhouse agricultural production and has wide practicability.
基金Sponsored by the National High Technology Research and Development Program of China(Grant 2007AA05Z3374)the Key Projects in the National Science & Technology Pillar Program during the Eleventh Five-Year Plan Period(Grant No.2006BAA01B04)
文摘Basing on some researchers' experimental results,the droplet impinging wall model was modified,and We Number and K Number were adopted to determine the mode of droplet impinging wall.The simulation results indicated that the mode of impinging droplet is sticking on the wall in Muti-spout bed.The droplet impinging wall model modified can describe the droplet impinging wall phenomenon accurately in the multistage spouted fluidized flue gas desulfurization reactor.Basing on the study above,the distributions of temperature and relative humidity in the reactor were attained.In atomization region,the distribution of temperature exhibits "M" shape.The relative humidity exhibits"W"shape.The mass concentration of droplet reduces along axis of the reactor.Due to the multi-spouted configuration,droplet concentration increases obviously in the intersection region between the 1st and 2nd stage reaction region.The evaporating intensity reaches its peak value in the area of 200 mm away from the sprayer,and droplets are completely evaporated at 1500 mm.
基金National Natural Science Foundation of China(41901297,41806209)Science and Technology Key Project of Henan Province(202102310017)+1 种基金Key Research Projects for the Universities of Henan Province(20A170013)China Postdoctoral Science Foundation(2021M693201)。
文摘As a typical physical retrieval algorithm for retrieving atmospheric parameters,one-dimensional variational(1 DVAR)algorithm is widely used in various climate and meteorological communities and enjoys an important position in the field of microwave remote sensing.Among algorithm parameters affecting the performance of the 1 DVAR algorithm,the accuracy of the microwave radiative transfer model for calculating the simulated brightness temperature is the fundamental constraint on the retrieval accuracies of the 1 DVAR algorithm for retrieving atmospheric parameters.In this study,a deep neural network(DNN)is used to describe the nonlinear relationship between atmospheric parameters and satellite-based microwave radiometer observations,and a DNN-based radiative transfer model is developed and applied to the 1 DVAR algorithm to carry out retrieval experiments of the atmospheric temperature and humidity profiles.The retrieval results of the temperature and humidity profiles from the Microwave Humidity and Temperature Sounder(MWHTS)onboard the Feng-Yun-3(FY-3)satellite show that the DNN-based radiative transfer model can obtain higher accuracy for simulating MWHTS observations than that of the operational radiative transfer model RTTOV,and also enables the 1 DVAR algorithm to obtain higher retrieval accuracies of the temperature and humidity profiles.In this study,the DNN-based radiative transfer model applied to the 1 DVAR algorithm can fundamentally improve the retrieval accuracies of atmospheric parameters,which may provide important reference for various applied studies in atmospheric sciences.
基金Supported by the Project of Education Department of Sichuan Province,China(16ZB0365)Project of Sichuan Minzu College(XYZB18041SB).
文摘Based on the climate observation data of Kangding City in recent 60 years,the changing trends of temperature and humidity index and wind efficiency index in Kangding City are analyzed.The results show that the annual average temperature and humidity index and wind efficiency index of Kangding in recent 60 years showed an upward trend,which is consistent with global warming climate.Temperature and humidity index tended to change from the cold grade to the relatively cold and cool grades,and wind efficiency index changed from the slightly cold wind grade to the cool wind grade.Seen from temperature and humidity index and wind efficiency index,the climate was comfortable and relatively comfortable from May to September,which will become an important climatic reference to attract tourists.
文摘In order to facilitate the determination of the calendar life of mechanical parts,the author summarized his relevant research papers that had studied for many years as eight distinct topics:(A).The principle and method for compiling the equal-damage temperature and humidity spectrum;(B).The principle for preparing the high concentration medium solution;(C).The principle and method for determining the metal calendar life;(D).The principle and method for determining the protective coating calendar life;(E).The principle and method for determining the total calendar life;(F).The principle of the reliability processing;(G).The principle and method for determining the corrosion damage tolerance;(H).The principle and matching design method to ensure that the total fatigue life and the total calendar life of the mechanical part were safe simultaneously.The above contents established a complete set of theoretical systems and methods for determining the calendar life.
基金The authors express gratitude for the support of the National Key Research and Development Program of China(No.2018YFB0905103)the National Natural Science Foundation of China(No.51806213)Beijing Key Laboratory of Distributed Combined Cooling Heating and Power System.
文摘Traditional condensing air-conditioning systems consume large amounts of energy in hot and humid areas,and it is difficult to achieve simultaneous control of temperature and humidity.A combined absorption refrigeration(AR)and liquid desiccant dehumidification(LDD)air-conditioning system based on cascade utilization of low-grade heat source is proposed.The system can realize independent control of temperature and humidity and carry out profound recovery of low-grade heat sources.Under the design conditions,the heat utilization rate C reaches 21.05%,which is 2.73 times that of the conventional absorption refrigeration reference system.A parametric sensitivity analysis is performed to optimize the system.The C increases from 9.79%to 18.55%and the coefficient of performance C O P t increases from 0.33 to 0.35 with an increase in chilled water temperature from 7°C to 15°C.With an increase in regenerant solution temperature from 60°C to 70°C,the C achieves the optimal value of 21.05%at 68°C.C decreases from 21.05%to 15.05%as the concentration of the regenerant solution increases from 36%to 40%.Under variable environmental temperature and humidity,the C the proposed system changes within a small range and stays much higher than that of the reference system with the same quality heat source,which indicates that the proposed system has a better adaptability to changing environmental parameters.
基金Supported by the National Key Research and Development Program of China(2018YFC1506802)National Natural Science Foundation of China(41705087)。
文摘The green vegetation fraction(GVF)can greatly influence the partitioning of surface sensible and latent heat fluxes in numerical weather prediction(NWP)models.However,the multiyear averaged monthly GVF climatology—the most commonly used representation of the vegetation state in models—cannot capture the real-time vegetation state well.In this study,a near real-time(NRT)GVF dataset generated from an 8-day composite of the normalized difference vegetation index is compared with the 10-yr averaged monthly GVF provided by the WRF model.The annual variability of the GVF over North China is examined in detail.Many differences between the two GVF datasets are found over dryland,grassland,and cropland/grassland mosaic areas.Two experiments using different GVF datasets are performed to assess the impacts of GVF on forecasts of screen-level temperature and humidity.The results show that using NRT GVF can lead to a widespread reduction of 2-m temperature forecast errors from April to October.Evaluation against in-situ observations shows that the positive impact on 2-m temperature forecasts in the morning is more distinct than that in the afternoon.Our study demonstrates that NRT GVF can provide a more realistic representation of the vegetation state,which in turn helps to improve short-range forecasts in arid and semiarid regions of North China.Moreover,our study shows that the negative effect of using NRT GVF is closely related to the initial soil moisture.