Pediatric type 1 diabetes(T1D)is a lifelong condition requiring meticulous glucose management to prevent acute and chronic complications.Conventional management of diabetic patients does not allow for continuous monit...Pediatric type 1 diabetes(T1D)is a lifelong condition requiring meticulous glucose management to prevent acute and chronic complications.Conventional management of diabetic patients does not allow for continuous monitoring of glucose trends,and can place patients at risk for hypo-and hyperglycemia.Continuous glucose monitors(CGMs)have emerged as a mainstay for pediatric diabetic care and are continuing to advance treatment by providing real-time blood glucose(BG)data,with trend analysis aided by machine learning(ML)algorithms.These predictive analytics serve to prevent against dangerous BG variations in the perioperative environment for fasted children undergoing surgical stress.Integration of CGM data into electronic health records(EHR)is essential,as it establishes a foundation for future technologic interfaces with artificial intelligence(AI).Challenges in perioperative CGM implementation include equitable device access,protection of patient privacy and data accuracy,ensuring institution of standardized protocols,and financing the cumbersome healthcare costs associated with staff training and technology platforms.This paper advocates for implementation of CGM data into the EHR utilizing multiple facets of AI/ML algorithms.展开更多
The structural dynamic response reconstruction technology can extract unmeasured information from limited measured data,significantly impacting vibration control,load identification,parameter identification,fault diag...The structural dynamic response reconstruction technology can extract unmeasured information from limited measured data,significantly impacting vibration control,load identification,parameter identification,fault diagnosis,and related fields.This paper proposes a dynamic response reconstruction method based on the Kalman filter,which simultaneously identifies external excitation and reconstructs dynamic responses at unmeasured positions.The weighted least squares method determines the load weighting matrix for excitation identification,while the minimum variance unbiased estimation determines the Kalman filter gain.The excitation prediction Kalman filter is constructed through time,excitation,and measurement updates.Subsequently,the response at the target point is reconstructed using the state vector,observation matrix,and excitation influence matrix obtained through the excitation prediction Kalman filter algorithm.An algorithm for reconstructing responses in continuous system using the excitation prediction Kalman filtering algorithm in modal space is derived.The proposed structural dynamic response reconstruction method evaluates the response reconstruction and the load identification performance under various load types and errors through simulation examples.Results demonstrate the accurate excitation identification under different load conditions and simultaneous reconstruction of target point responses,verifying the feasibility and reliability of the proposed method.展开更多
Crops produced using the practice of continuous cropping can become seriously damaged by plant-parasitic nematodes,an important indicator of continuous cropping obstacles.As a typical and important perennial economic ...Crops produced using the practice of continuous cropping can become seriously damaged by plant-parasitic nematodes,an important indicator of continuous cropping obstacles.As a typical and important perennial economic crop,dragon fruit is prone to serious plant-parasitic nematode infestation;however,whether it encounters continuous cropping obstacles remains unclear.Here,we studied plant-parasitic nematodes(Meloidogyne spp.and Tylenchorhynchus sp.)in the soil and roots,soil nematode communities,metabolic footprint,soil integrated fertility,and the yield of intensively planted dragon fruit under non-continuous cropping(Y1)and 3 years(Y3)and 5 years(Y5)of continuous cropping,to determine potential continuous-cropping obstacles and factors that affect the yield of this fruit.The largest numbers of plant-parasitic nematodes in the soil and roots were observed in Y5;the associated yield was reduced,and the dragon fruit was severely stressed.Further analysis of the composition,diversity,and ecological function indices of soil nematodes showed that the soil ecological environment deteriorated after 3 years of continuous cropping,with Y5 having the worst results.Similarly,the soil at Y5 had a significant inhibitory effect on the growth and reproduction of Caenorhabditis elegans.Mantel test analysis and a random forest model showed that soil available phosphorus,soil exchange calcium,and soil nematode abundance and diversity were related significantly to yield.Partial least squares path modeling revealed that soil fertility and soil nematode diversity directly impacts the yield of continuously cropped dragon fruit.In summary,continuous cropping obstacles occurred in Y5 of intensive dragon fruit cultivation,with soil nematode diversity and soil fertility determining the crop's yield.展开更多
To address the current issues with the conventional slide gate system utilized in the steel teeming process,a unique electromagnetic induction controlled automated steel teeming(EICAST)technology has been developed.Co...To address the current issues with the conventional slide gate system utilized in the steel teeming process,a unique electromagnetic induction controlled automated steel teeming(EICAST)technology has been developed.Cooling means of spiral coil in this technology is directly related to its service life.Firstly,heat transfer processes of air cooling and spray cooling were compared and analyzed.Secondly,the impacts of water temperature,water flow rate and air flow rate were examined in order to maximize the spray cooling effect.To maintain coil temperature at a low value consistently throughout the entire thermal cycle process of the ladle,a combined cooling mode was finally employed.Numerical simulation was applied to examine the coil temperature variation with different cooling systems and characteristics.Before coil operation,spray cooling is said to be more effective.By controlling the water flow rate and air flow rate,the spray cooling effect is enhanced.However,water temperature has little or no impact when using spray cooling.Air cooling during the secondary refining process and spray cooling prior to coil operation are combined to further lower coil temperature.When the direction of the spray cooling is from bottom to top,the coil temperature is lowered below 165℃.A practical induction coil cooling plan was provided for the EICAST technology’s production process.展开更多
To handle input and output time delays that commonly exist in many networked control systems(NCSs), a new robust continuous sliding mode control(CSMC) scheme is proposed for the output tracking in uncertain single inp...To handle input and output time delays that commonly exist in many networked control systems(NCSs), a new robust continuous sliding mode control(CSMC) scheme is proposed for the output tracking in uncertain single input-single-output(SISO) networked control systems. This scheme consists of three consecutive steps. First, although the network-induced delay in those systems can be effectively handled by using Pade approximation(PA), the unmatched disturbance cames out as another difficulty in the control design. Second, to actively estimate this unmatched disturbance, a generalized proportional integral observer(GPIO) technique is utilized based on only one measured state. Third, by constructing a new sliding manifold with the aid of the estimated unmatched disturbance and states, a GPIO-based CSMC is synthesized, which is employed to cope with not only matched and unmatched disturbances, but also networkinduced delays. The stability of the entire closed-loop system under the proposed GPIO-based CSMC is detailedly analyzed.The promising tracking efficiency and feasibility of the proposed control methodology are verified through simulations and experiments on Quanser's servo module for motion control under various test conditions.展开更多
[Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting L...[Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting Lake area, four treatments as no fertilizer （CK）, urea, controlled release nitrogen fertilizer （CRNF） and 70% controlled release nitrogen fertilizer （70% CRNF） were designed in the micro-plot trials from 2005 to 2008. [Result] The rice yield in treatment CRNF at N 150 kg/hm2 was increased by 10.3%, 8.0% and 2.4% compared with treatment of urea, in alluvial sandy loamy paddy soil （ALS）, purple calcareous clayey paddy soil （PCS）, and reddish yellow loamy paddy soil （RYS）, respectively; and the yield in treatment of 70% CRNF was increased by 6.1%, 2.6% and -0.8%, respectively. The ranking order of nitrogen uptake amount by plant in early rice and late rice was CRNF 70% CRNF urea CK in all three types of soil. Nitrogen utilization efficiency of CRNF in above three types of soil was 60.7%, 59.6% and 56.3%, increased by 23.8%, 19.4% and 16.3% compared with that in treatment of urea, respectively. Nitrogen utilization efficiency of CRNF in early rice was increased year by year, and was higher than that of 70% CRNF during the whole experiment stage, while that in late rice was increased first and then decreased from the 3rd year. [Conclusion] Continuous application CRNF could alleviate the decreasing of soil nitrogen fertility and organic carbon especially in ALS, increase rice yield and nitrogen utilization efficiency in double-rice cropping system.展开更多
[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the...[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the simulating rumen fer- mentation effect in vitro culture system was evaluated. [Result] The simulation rumen fermentation test needed adaptive phase of 2-3 d, and the fermentation state was relatively stable within 3-9 d, with good effects. The test showed certain regularity variation with index value of rumen in vivo. [Conclusion] The continuous culture sys- tem of artificial rumen could be used as the ideal model to study the rumen fermen- tation in vivo.展开更多
[Objective] This study aimed to achieve high yield and stable yield of win- ter wheat-summer maize rotation system and provide basis for rational application of nitrogen fertilizer. [Method] Effects of continuous nitr...[Objective] This study aimed to achieve high yield and stable yield of win- ter wheat-summer maize rotation system and provide basis for rational application of nitrogen fertilizer. [Method] Effects of continuous nitrogen application on grain yield, economic profit, nitrogen uptake and utilization efficiency, and soil inorganic nitrogen accumulation in winter wheat-summer maize rotation system were investigated. [Re- sult] Nitrogen application could significantly increase the y（eld of the winter wheat- summer maize rotation system, which increased by 17.76%-30.32% and 22.24%- 46.63% in two rotation cycles, respectively. The yield of the winter wheat-summer maize rotation system was the maximum in two rotation cycles with nitrogen appli- cation amount of 660.0 kg/hm2, which reached respectively 23 391.19 and 23 444.35 kg/hm2, the yield and economic benefit were the highest, the nitrogen fertilizer use efficiency was 22.2% and 30.7%, the agronomic efficiency was 8.3 and 11.3 kg/kg. However, the nitrogen fertilizer use efficiency and agronomic efficiency between ni- trogen application amount of 540.0 and 660.0 kg/hm2 showed no significant differ- ence. After two rotation cycles, inorganic nitrogen accumulation in 0-40 cm soil with nitrogen application amount of 540.0 kg/hm2 was almost equal to that before experi- ment. [Conclusion] Under the experimental conditions, comprehensively considering the grain yield, economic profit, nitrogen fertilizer efficiency and soil inorganic nitro- gen balance, the optimal nitrogen application amount was 625.3-660.0 kg/hm2 in high-yield winter wheat-summer maize rotation system.展开更多
An example is presented to introduce the concept of implicit continuity proposed as contrasted with the explicit continuity.A sufficient and necessary condition of the implicit continuity is given and proved in forms ...An example is presented to introduce the concept of implicit continuity proposed as contrasted with the explicit continuity.A sufficient and necessary condition of the implicit continuity is given and proved in forms of implicit system.This condition also offers the solution of initial values at the points where the dynamic system is discontinuous.Some discussions are contributed to the physical significance of implicit continuity.展开更多
In order to let suppliers monitor customers＇ inventory levels and make supply decisions regarding order quantities and delivery time, an integrated continuous replenishment planning （CRP） strategy of fresh food ori...In order to let suppliers monitor customers＇ inventory levels and make supply decisions regarding order quantities and delivery time, an integrated continuous replenishment planning （CRP） strategy of fresh food oriented to retail industry is presented, which integrates the consolidation of shipment and inventory replenishment considering the deterioration of items to guarantee the quality safety of fresh food during the replenishment cycle. A vendor managed inventory （VMI） mathematical model to compute upper-level inventory and delivery cycle is built. Based on the real-time sales data exchange, it enables suppliers to make the decision of the optimal time and the quantities of replenishment for retailers during a delivery cycle, in order to replenish the consumers＇ stock initiatively and minimize the long-run average cost.展开更多
To improve billet quality and the trackability and stability of secondary cooling water during continuous casting, the superheat is introduced into the water distribution for secondary cooling to design the relevant c...To improve billet quality and the trackability and stability of secondary cooling water during continuous casting, the superheat is introduced into the water distribution for secondary cooling to design the relevant control system, based on the water distribution model, superheat and fuzzy self-adaptive PID （process identity） . A spray cooling system is set up for simulation test in laboratory to test the step signal from the conventional, integral sepa rated and fuzzy self-adaptive PID controllers and the simulation casting. And the on-site test is done in some steel plant. The test results show that the fuzzy self-adaptive PID controller＇s performance is better than that of the other two controllers, which provides a basis for further study and application.展开更多
BACKGROUND Cardiogenic shock (CS) secondary to acute myocardial infarction (AMI) complicates management of the condition, and often leads to poor prognosis. Prompt and accurate monitoring of cardiovascular and accompa...BACKGROUND Cardiogenic shock (CS) secondary to acute myocardial infarction (AMI) complicates management of the condition, and often leads to poor prognosis. Prompt and accurate monitoring of cardiovascular and accompanying hemodynamic changes is crucial in achieving adequate management of the condition. Advances in technology has availed procedures such as pulse index continuous cardiac output (PiCCO), which can offer precise monitoring of cardiovascular functions and hemodynamic parameters. In this study, PiCCO is evaluated for its potential utility in improving management and clinical outcomes among elderly patients with AMI complicated by CS. AIM To assess whether use of the PiCCO system can improve clinical outcomes in elderly patients with AMI complicated by CS.METHODS Patients from emergency intensive care units (EICU) or coronary care units (CCU) were randomized to receive PiCCO monitoring or not. The APACHE II score, SOFA score, hs-TnI, NT-proBNP, PaO2/FiO2 ratio and lactate levels on day 1, 3 and 7 after treatment were compared. The infusion and urine volume at 0-24 h, 24-48 h and 48-72 h were recorded, as were the cardiac index (CI), extravascular lung water index (EVLWI), intrathoracic blood volume index (ITBVI) and global end diastolic volume index (GEDVI) at similar time intervals. RESULTS Sixty patients with AMI complicated by CS were included in the study. The PiCCO group had a significantly lower APACHE II score, SOFA score, hs-TnI and NT-proBNP levels on day 1, 3 and 7 after treatment. The infusion and urine volume during 0-24 h in the PiCCO group were significantly greater, and this group also showed significantly higher ADL scores. Furthermore, the PiCCO group spent lesser days on vasoactive agents, mechanical ventilation, and had a reduced length of stay in EICU/CCU. Additionally, the CI was significantly higher at 48 h and 72 h in the PiCCO group compared with that at 24 h, and the EVLWI, ITBVI and GEDVI were significantly decreased at 48 h and 72 h. CONCLUSION Applying the PiCCO system could improve the clinical outcomes of elderly patients with AMI complicated by CS.展开更多
An integrated coupling element considering wheel-rail interface for analyzing the dynamic responses of vehicle-rail-bridge interaction system with a non-uniform continuous bridge is presented. The governing equations ...An integrated coupling element considering wheel-rail interface for analyzing the dynamic responses of vehicle-rail-bridge interaction system with a non-uniform continuous bridge is presented. The governing equations of the interaction system are established first, and the solution procedure and assembly method of the coupling element are demonstrated. Finally, the accuracy, efficiency and function of the integrated coupling element are tested using two numerical examples. The influences of different combinations of rail and bridge element length in the coupling element on the solution are investigated, and the effects of different rail irregularities on the dynamic responses are discussed.展开更多
Ant colony algorithms comprise a novel category of evolutionary computation methods for optimization problems, especially for sequencing-type combinatorial optimization problems. An adaptive ant colony algorithm is pr...Ant colony algorithms comprise a novel category of evolutionary computation methods for optimization problems, especially for sequencing-type combinatorial optimization problems. An adaptive ant colony algorithm is proposed in this paper to tackle continuous-space optimization problems, using a new objective-function-based heuristic pheromone assignment approach for pheromone update to filtrate solution candidates.Global optimal solutions can be reached more rapidly by self-adjusting the path searching behaviors of the ants according to objective values. The performance of the proposed algorithm is compared with a basic ant colony algorithm and a Square Quadratic Programming approach in solving two benchmark problems with multiple extremes. The results indicated that the efficiency and reliability of the proposed algorithm were greatly improved.展开更多
With the help of similar material simulation test,time series system for induced caving of roof in continuous mining under complex backfill in ore body No.92 of Tongkeng Tin Mine was studied. According to the similari...With the help of similar material simulation test,time series system for induced caving of roof in continuous mining under complex backfill in ore body No.92 of Tongkeng Tin Mine was studied. According to the similarity theory,a two-dimensional similar simulation test-bed was constructed. The stress and displacement that change along with the advance of mining were acquired and analyzed automatically by data system. The processes of continuous mining of ore-block in 5 intervals and artificial induced caving of roof were simulated. The results of the test show that ore body remained as safety roof in thickness of 15 m guarantees the safe advance of stoping work face. Caving of safety roof puts in practice at the first two mining intervals when the third interval of continuous mining is finished,and one interval as the safety distance should be kept all the time between stopping and caving. While mining in the last interval,pre-slotting should be implemented first of all,and the roof of the last two mining intervals is caved simultaneously. Only this kind of time series system can be an efficient and safe way for induced caving of roof in continuous mining.展开更多
The dynamic interaction between maglev vehicle and three-span continuous guideway is discussed. With the consideration of control system, the dynamic interaction model has been developed. Numerical simulation has been...The dynamic interaction between maglev vehicle and three-span continuous guideway is discussed. With the consideration of control system, the dynamic interaction model has been developed. Numerical simulation has been performed to study dynamic characteristics of the guideway. The results show that bending rigidity, vehicle speed, span ratio and primary frequency all have important influences on the dynamic characteristics of the guideway and there is no distinct trend towards resonance vibration when fl/（v/l） equals 1.0. The definite way is to control impact coefficient and acceleration of the guideway. The conclusions can serve the design of high-speed maglev three-span continuous guideway.展开更多
Dehydrating large amounts of sludge produced by sewage treatment plants is difficult.Microwave pretreatment can effectively and significantly improve the dewaterability and hydrogen production of sludge subjected to a...Dehydrating large amounts of sludge produced by sewage treatment plants is difficult.Microwave pretreatment can effectively and significantly improve the dewaterability and hydrogen production of sludge subjected to anaerobic digestion. The aim of this study was to investigate the effects of different microwave conditions on hydrogen production from anaerobic digestion and dewaterability of sludge. Based on an analysis of the electric field distribution, a spiral reactor was designed and a continuous microwave system was built to conduct intermittent and continuous experiments under different conditions. Settling Volume, Capillary Suction Time, particle size, and moisture content of the sludge were measured. The results show that sludge pretreatment in continuous experiments has equally remarkable dehydration performance as in intermittent experiments; the minimum moisture content was 77.29% in the intermittent experiment under a microwave power of 300 W and an exposure time of 60 sec, and that in the continuous experiment was 77.56% under a microwave power of 400 W and an exposure time of 60 sec.The peak measured by Differential Scanning Calorimeter appeared earliest under a microwave power of 600 W and an exposure time of 180 sec. The heat flux at the peak was 4.343 W/g, which is relatively small. This indicates that microwave pretreatment induced desirable effects. The maximum yield of hydrogen production was 7.967% under the conditions of microwave power of 500 W, exposure time of 120 sec, and water bath at 55℃. This research provides a theoretical and experimental basis for the development of a continuous microwave sludge-conditioning system.展开更多
To design a power source system and mold for electromagnetic soft-contact continuous casting process and to theoretically estimate the heat losses from the charges and the system power, the effect of structure paramet...To design a power source system and mold for electromagnetic soft-contact continuous casting process and to theoretically estimate the heat losses from the charges and the system power, the effect of structure parameters on system power and magnetic flux density distribution was calculated using finite element method. The results show that as for electromagnetic soft-contact continuous casting system with partial-segment type mold, the power consumption is much more than that with a full-segment type mold; about 62% of electric power is dissipated in the mold, and the effective acting range of magnetic field is relatively narrow. Optimizing mold structure is a crucial measure of remarkably reducing mold power consumption and saving electric energy. Increasing slit number, width, and length can remarkably increase the magnetic flux density in the mold and can reduce the electric energy consumption. Among structure parameters, slit number and slit width are relatively more effective to reduce energy consumption. For a round billet electromagnetic continuous casting system with diameter of 178 ram, the reasonable slit number, width, and length are about 24--32, 0. 5--1.0 mm, and 160 mm, respectively.展开更多
Continuous homogenous azeotropic distillation(CHAD)and pressure-swing distillation(PSD)are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane.The CHAD process with acetone as the en...Continuous homogenous azeotropic distillation(CHAD)and pressure-swing distillation(PSD)are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane.The CHAD process with acetone as the entrainer and the PSD process with the pressures of 0.1 MPa and 0.6 MPa in two columns are designed and simulated by Aspen Plus.The operating conditions of the two processes are optimized via a sequential modular approach to obtain the minimum total annual cost(TAC).The computational results show that the partially heat integrated pressure-swing distillation(HIPSD)has reduced in the energy cost and TAC by 40.79%and 35.94%,respectively,than the conventional PSD,and has more greatly reduced the energy cost and TAC by 62.61%and 49.26%respectively compared with the CHAD process.The comparison of CHAD process and partially HIPSD process illustrates that the partially HIPSD has more advantages in averting the product pollution,energy saving,and economy.展开更多
To systematically study the vehicle-bridge coupled dynamic response and its change rule with different parameters, a vehicle model with seven degrees of freedom was built and the total potential energy of vehicle spac...To systematically study the vehicle-bridge coupled dynamic response and its change rule with different parameters, a vehicle model with seven degrees of freedom was built and the total potential energy of vehicle space vibration system was deduced. Considering the stimulation of road roughness, the dynamic response equation of vehicle-bridge coupled system was established in accordance with the elastic system principle of total potential energy with stationary value and the ＂set-in-right-position＂ rule. On the basis of the self-compiled Fortran program and bridge engineering, the dynamic response of long- span continuous girder bridge under vehicle load was studied. This study also included the calculation of vehicle impact coefficient, evaluation of vibration comfort, and analysis of dynamic response parameters. Results show the impact coefficient changes with lane number and is larger than the value calculated by the ＂general code for design of highway bridges and culverts （China）＂. The Dieckmann index of bridge vibration is also related to lane number, and the vibration comfort evaluation is good in normal conditions. The relevant conclusions from parametric analyses have practical significance to dynamic design and daily operation of long-span continuous girder bridges in expressways. Safety and comfort are expected to improve significantly with further control of the vibration of vehicle-bridge system.展开更多
文摘Pediatric type 1 diabetes(T1D)is a lifelong condition requiring meticulous glucose management to prevent acute and chronic complications.Conventional management of diabetic patients does not allow for continuous monitoring of glucose trends,and can place patients at risk for hypo-and hyperglycemia.Continuous glucose monitors(CGMs)have emerged as a mainstay for pediatric diabetic care and are continuing to advance treatment by providing real-time blood glucose(BG)data,with trend analysis aided by machine learning(ML)algorithms.These predictive analytics serve to prevent against dangerous BG variations in the perioperative environment for fasted children undergoing surgical stress.Integration of CGM data into electronic health records(EHR)is essential,as it establishes a foundation for future technologic interfaces with artificial intelligence(AI).Challenges in perioperative CGM implementation include equitable device access,protection of patient privacy and data accuracy,ensuring institution of standardized protocols,and financing the cumbersome healthcare costs associated with staff training and technology platforms.This paper advocates for implementation of CGM data into the EHR utilizing multiple facets of AI/ML algorithms.
基金supported by the National Natural Science Foundation of China(Nos.12372066,U23B6009,52171261)the Aeronautical Science Fund(No.20240013052002)the Qing Lan Project。
文摘The structural dynamic response reconstruction technology can extract unmeasured information from limited measured data,significantly impacting vibration control,load identification,parameter identification,fault diagnosis,and related fields.This paper proposes a dynamic response reconstruction method based on the Kalman filter,which simultaneously identifies external excitation and reconstructs dynamic responses at unmeasured positions.The weighted least squares method determines the load weighting matrix for excitation identification,while the minimum variance unbiased estimation determines the Kalman filter gain.The excitation prediction Kalman filter is constructed through time,excitation,and measurement updates.Subsequently,the response at the target point is reconstructed using the state vector,observation matrix,and excitation influence matrix obtained through the excitation prediction Kalman filter algorithm.An algorithm for reconstructing responses in continuous system using the excitation prediction Kalman filtering algorithm in modal space is derived.The proposed structural dynamic response reconstruction method evaluates the response reconstruction and the load identification performance under various load types and errors through simulation examples.Results demonstrate the accurate excitation identification under different load conditions and simultaneous reconstruction of target point responses,verifying the feasibility and reliability of the proposed method.
基金supported by the National Key Research and Development Program of China(2023YFD1700203and 2022YFD1901501)the Tianchi Talent Introduction Program of Xinjiang Autonomous Region,China(2023-“2+5”)the Tingzhou Talent Introduction Program of Changji Autonomous Region,China(2023)。
文摘Crops produced using the practice of continuous cropping can become seriously damaged by plant-parasitic nematodes,an important indicator of continuous cropping obstacles.As a typical and important perennial economic crop,dragon fruit is prone to serious plant-parasitic nematode infestation;however,whether it encounters continuous cropping obstacles remains unclear.Here,we studied plant-parasitic nematodes(Meloidogyne spp.and Tylenchorhynchus sp.)in the soil and roots,soil nematode communities,metabolic footprint,soil integrated fertility,and the yield of intensively planted dragon fruit under non-continuous cropping(Y1)and 3 years(Y3)and 5 years(Y5)of continuous cropping,to determine potential continuous-cropping obstacles and factors that affect the yield of this fruit.The largest numbers of plant-parasitic nematodes in the soil and roots were observed in Y5;the associated yield was reduced,and the dragon fruit was severely stressed.Further analysis of the composition,diversity,and ecological function indices of soil nematodes showed that the soil ecological environment deteriorated after 3 years of continuous cropping,with Y5 having the worst results.Similarly,the soil at Y5 had a significant inhibitory effect on the growth and reproduction of Caenorhabditis elegans.Mantel test analysis and a random forest model showed that soil available phosphorus,soil exchange calcium,and soil nematode abundance and diversity were related significantly to yield.Partial least squares path modeling revealed that soil fertility and soil nematode diversity directly impacts the yield of continuously cropped dragon fruit.In summary,continuous cropping obstacles occurred in Y5 of intensive dragon fruit cultivation,with soil nematode diversity and soil fertility determining the crop's yield.
基金supported by the Startup Foundation of Shenyang Agriculture University(No.X2023050)the Fundamental Research Funds for the Central Universities(No.N2209006)the National Natural Science Foundation of China(No.U22A20173).
文摘To address the current issues with the conventional slide gate system utilized in the steel teeming process,a unique electromagnetic induction controlled automated steel teeming(EICAST)technology has been developed.Cooling means of spiral coil in this technology is directly related to its service life.Firstly,heat transfer processes of air cooling and spray cooling were compared and analyzed.Secondly,the impacts of water temperature,water flow rate and air flow rate were examined in order to maximize the spray cooling effect.To maintain coil temperature at a low value consistently throughout the entire thermal cycle process of the ladle,a combined cooling mode was finally employed.Numerical simulation was applied to examine the coil temperature variation with different cooling systems and characteristics.Before coil operation,spray cooling is said to be more effective.By controlling the water flow rate and air flow rate,the spray cooling effect is enhanced.However,water temperature has little or no impact when using spray cooling.Air cooling during the secondary refining process and spray cooling prior to coil operation are combined to further lower coil temperature.When the direction of the spray cooling is from bottom to top,the coil temperature is lowered below 165℃.A practical induction coil cooling plan was provided for the EICAST technology’s production process.
基金supported in part by the Australian Research Council Discovery Project(DP190101557)
文摘To handle input and output time delays that commonly exist in many networked control systems(NCSs), a new robust continuous sliding mode control(CSMC) scheme is proposed for the output tracking in uncertain single input-single-output(SISO) networked control systems. This scheme consists of three consecutive steps. First, although the network-induced delay in those systems can be effectively handled by using Pade approximation(PA), the unmatched disturbance cames out as another difficulty in the control design. Second, to actively estimate this unmatched disturbance, a generalized proportional integral observer(GPIO) technique is utilized based on only one measured state. Third, by constructing a new sliding manifold with the aid of the estimated unmatched disturbance and states, a GPIO-based CSMC is synthesized, which is employed to cope with not only matched and unmatched disturbances, but also networkinduced delays. The stability of the entire closed-loop system under the proposed GPIO-based CSMC is detailedly analyzed.The promising tracking efficiency and feasibility of the proposed control methodology are verified through simulations and experiments on Quanser's servo module for motion control under various test conditions.
基金Supported by the National Key Technology Research and Development Program of China during the11th Five-Year Plan Period(2008BADA4B08)Science and Technology Innovation Project of Hunan Academy of Agricultural Sciences(2010hnnkycx56)~~
文摘[Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting Lake area, four treatments as no fertilizer （CK）, urea, controlled release nitrogen fertilizer （CRNF） and 70% controlled release nitrogen fertilizer （70% CRNF） were designed in the micro-plot trials from 2005 to 2008. [Result] The rice yield in treatment CRNF at N 150 kg/hm2 was increased by 10.3%, 8.0% and 2.4% compared with treatment of urea, in alluvial sandy loamy paddy soil （ALS）, purple calcareous clayey paddy soil （PCS）, and reddish yellow loamy paddy soil （RYS）, respectively; and the yield in treatment of 70% CRNF was increased by 6.1%, 2.6% and -0.8%, respectively. The ranking order of nitrogen uptake amount by plant in early rice and late rice was CRNF 70% CRNF urea CK in all three types of soil. Nitrogen utilization efficiency of CRNF in above three types of soil was 60.7%, 59.6% and 56.3%, increased by 23.8%, 19.4% and 16.3% compared with that in treatment of urea, respectively. Nitrogen utilization efficiency of CRNF in early rice was increased year by year, and was higher than that of 70% CRNF during the whole experiment stage, while that in late rice was increased first and then decreased from the 3rd year. [Conclusion] Continuous application CRNF could alleviate the decreasing of soil nitrogen fertility and organic carbon especially in ALS, increase rice yield and nitrogen utilization efficiency in double-rice cropping system.
文摘[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the simulating rumen fer- mentation effect in vitro culture system was evaluated. [Result] The simulation rumen fermentation test needed adaptive phase of 2-3 d, and the fermentation state was relatively stable within 3-9 d, with good effects. The test showed certain regularity variation with index value of rumen in vivo. [Conclusion] The continuous culture sys- tem of artificial rumen could be used as the ideal model to study the rumen fermen- tation in vivo.
基金Supported by Science and Technology Project for Food Production(2011BAD16B15)"11th Five-Year Plan"National Science and Technology Support Program(2008-BADA4B07)Sino-International Plant Nutrition Research Institute(IPNI)Cooperation Project(NMBF-HenanAU-2008)~~
文摘[Objective] This study aimed to achieve high yield and stable yield of win- ter wheat-summer maize rotation system and provide basis for rational application of nitrogen fertilizer. [Method] Effects of continuous nitrogen application on grain yield, economic profit, nitrogen uptake and utilization efficiency, and soil inorganic nitrogen accumulation in winter wheat-summer maize rotation system were investigated. [Re- sult] Nitrogen application could significantly increase the y（eld of the winter wheat- summer maize rotation system, which increased by 17.76%-30.32% and 22.24%- 46.63% in two rotation cycles, respectively. The yield of the winter wheat-summer maize rotation system was the maximum in two rotation cycles with nitrogen appli- cation amount of 660.0 kg/hm2, which reached respectively 23 391.19 and 23 444.35 kg/hm2, the yield and economic benefit were the highest, the nitrogen fertilizer use efficiency was 22.2% and 30.7%, the agronomic efficiency was 8.3 and 11.3 kg/kg. However, the nitrogen fertilizer use efficiency and agronomic efficiency between ni- trogen application amount of 540.0 and 660.0 kg/hm2 showed no significant differ- ence. After two rotation cycles, inorganic nitrogen accumulation in 0-40 cm soil with nitrogen application amount of 540.0 kg/hm2 was almost equal to that before experi- ment. [Conclusion] Under the experimental conditions, comprehensively considering the grain yield, economic profit, nitrogen fertilizer efficiency and soil inorganic nitro- gen balance, the optimal nitrogen application amount was 625.3-660.0 kg/hm2 in high-yield winter wheat-summer maize rotation system.
文摘An example is presented to introduce the concept of implicit continuity proposed as contrasted with the explicit continuity.A sufficient and necessary condition of the implicit continuity is given and proved in forms of implicit system.This condition also offers the solution of initial values at the points where the dynamic system is discontinuous.Some discussions are contributed to the physical significance of implicit continuity.
文摘In order to let suppliers monitor customers＇ inventory levels and make supply decisions regarding order quantities and delivery time, an integrated continuous replenishment planning （CRP） strategy of fresh food oriented to retail industry is presented, which integrates the consolidation of shipment and inventory replenishment considering the deterioration of items to guarantee the quality safety of fresh food during the replenishment cycle. A vendor managed inventory （VMI） mathematical model to compute upper-level inventory and delivery cycle is built. Based on the real-time sales data exchange, it enables suppliers to make the decision of the optimal time and the quantities of replenishment for retailers during a delivery cycle, in order to replenish the consumers＇ stock initiatively and minimize the long-run average cost.
基金Item Sponsored by National High Technology Research and Development Program of China(2007AA04Z194)Major State Basic Research Development Program of China(2007CB613701)+1 种基金National Natural Science Foundation of China(51004032)Fundamental Research Funds for Central Universities of China(NO90409002)
文摘To improve billet quality and the trackability and stability of secondary cooling water during continuous casting, the superheat is introduced into the water distribution for secondary cooling to design the relevant control system, based on the water distribution model, superheat and fuzzy self-adaptive PID （process identity） . A spray cooling system is set up for simulation test in laboratory to test the step signal from the conventional, integral sepa rated and fuzzy self-adaptive PID controllers and the simulation casting. And the on-site test is done in some steel plant. The test results show that the fuzzy self-adaptive PID controller＇s performance is better than that of the other two controllers, which provides a basis for further study and application.
文摘BACKGROUND Cardiogenic shock (CS) secondary to acute myocardial infarction (AMI) complicates management of the condition, and often leads to poor prognosis. Prompt and accurate monitoring of cardiovascular and accompanying hemodynamic changes is crucial in achieving adequate management of the condition. Advances in technology has availed procedures such as pulse index continuous cardiac output (PiCCO), which can offer precise monitoring of cardiovascular functions and hemodynamic parameters. In this study, PiCCO is evaluated for its potential utility in improving management and clinical outcomes among elderly patients with AMI complicated by CS. AIM To assess whether use of the PiCCO system can improve clinical outcomes in elderly patients with AMI complicated by CS.METHODS Patients from emergency intensive care units (EICU) or coronary care units (CCU) were randomized to receive PiCCO monitoring or not. The APACHE II score, SOFA score, hs-TnI, NT-proBNP, PaO2/FiO2 ratio and lactate levels on day 1, 3 and 7 after treatment were compared. The infusion and urine volume at 0-24 h, 24-48 h and 48-72 h were recorded, as were the cardiac index (CI), extravascular lung water index (EVLWI), intrathoracic blood volume index (ITBVI) and global end diastolic volume index (GEDVI) at similar time intervals. RESULTS Sixty patients with AMI complicated by CS were included in the study. The PiCCO group had a significantly lower APACHE II score, SOFA score, hs-TnI and NT-proBNP levels on day 1, 3 and 7 after treatment. The infusion and urine volume during 0-24 h in the PiCCO group were significantly greater, and this group also showed significantly higher ADL scores. Furthermore, the PiCCO group spent lesser days on vasoactive agents, mechanical ventilation, and had a reduced length of stay in EICU/CCU. Additionally, the CI was significantly higher at 48 h and 72 h in the PiCCO group compared with that at 24 h, and the EVLWI, ITBVI and GEDVI were significantly decreased at 48 h and 72 h. CONCLUSION Applying the PiCCO system could improve the clinical outcomes of elderly patients with AMI complicated by CS.
基金Project supported by the National Natural Science Foundation of China(No.51078164)
文摘An integrated coupling element considering wheel-rail interface for analyzing the dynamic responses of vehicle-rail-bridge interaction system with a non-uniform continuous bridge is presented. The governing equations of the interaction system are established first, and the solution procedure and assembly method of the coupling element are demonstrated. Finally, the accuracy, efficiency and function of the integrated coupling element are tested using two numerical examples. The influences of different combinations of rail and bridge element length in the coupling element on the solution are investigated, and the effects of different rail irregularities on the dynamic responses are discussed.
文摘Ant colony algorithms comprise a novel category of evolutionary computation methods for optimization problems, especially for sequencing-type combinatorial optimization problems. An adaptive ant colony algorithm is proposed in this paper to tackle continuous-space optimization problems, using a new objective-function-based heuristic pheromone assignment approach for pheromone update to filtrate solution candidates.Global optimal solutions can be reached more rapidly by self-adjusting the path searching behaviors of the ants according to objective values. The performance of the proposed algorithm is compared with a basic ant colony algorithm and a Square Quadratic Programming approach in solving two benchmark problems with multiple extremes. The results indicated that the efficiency and reliability of the proposed algorithm were greatly improved.
基金Project(50490274) supported by the National Natural Science Foundation of ChinaProject(20050533035) supported by the Specialized Research Fund for the Doctoral Program of Higher Education of ChinaProject(1343-77236) supported by the Doctor Degree Paper Innovation Engineering of Central South University, China
文摘With the help of similar material simulation test,time series system for induced caving of roof in continuous mining under complex backfill in ore body No.92 of Tongkeng Tin Mine was studied. According to the similarity theory,a two-dimensional similar simulation test-bed was constructed. The stress and displacement that change along with the advance of mining were acquired and analyzed automatically by data system. The processes of continuous mining of ore-block in 5 intervals and artificial induced caving of roof were simulated. The results of the test show that ore body remained as safety roof in thickness of 15 m guarantees the safe advance of stoping work face. Caving of safety roof puts in practice at the first two mining intervals when the third interval of continuous mining is finished,and one interval as the safety distance should be kept all the time between stopping and caving. While mining in the last interval,pre-slotting should be implemented first of all,and the roof of the last two mining intervals is caved simultaneously. Only this kind of time series system can be an efficient and safe way for induced caving of roof in continuous mining.
基金Project (No. 2005AA505440) supported by the Hi-Tech Researchand Development Program (863) of China
文摘The dynamic interaction between maglev vehicle and three-span continuous guideway is discussed. With the consideration of control system, the dynamic interaction model has been developed. Numerical simulation has been performed to study dynamic characteristics of the guideway. The results show that bending rigidity, vehicle speed, span ratio and primary frequency all have important influences on the dynamic characteristics of the guideway and there is no distinct trend towards resonance vibration when fl/（v/l） equals 1.0. The definite way is to control impact coefficient and acceleration of the guideway. The conclusions can serve the design of high-speed maglev three-span continuous guideway.
基金supported by a National Natural Science Fund project(No.51104022)teacher team construction Top-notch Youth Project(municipal)(No.PXM2016 014222 000043)
文摘Dehydrating large amounts of sludge produced by sewage treatment plants is difficult.Microwave pretreatment can effectively and significantly improve the dewaterability and hydrogen production of sludge subjected to anaerobic digestion. The aim of this study was to investigate the effects of different microwave conditions on hydrogen production from anaerobic digestion and dewaterability of sludge. Based on an analysis of the electric field distribution, a spiral reactor was designed and a continuous microwave system was built to conduct intermittent and continuous experiments under different conditions. Settling Volume, Capillary Suction Time, particle size, and moisture content of the sludge were measured. The results show that sludge pretreatment in continuous experiments has equally remarkable dehydration performance as in intermittent experiments; the minimum moisture content was 77.29% in the intermittent experiment under a microwave power of 300 W and an exposure time of 60 sec, and that in the continuous experiment was 77.56% under a microwave power of 400 W and an exposure time of 60 sec.The peak measured by Differential Scanning Calorimeter appeared earliest under a microwave power of 600 W and an exposure time of 180 sec. The heat flux at the peak was 4.343 W/g, which is relatively small. This indicates that microwave pretreatment induced desirable effects. The maximum yield of hydrogen production was 7.967% under the conditions of microwave power of 500 W, exposure time of 120 sec, and water bath at 55℃. This research provides a theoretical and experimental basis for the development of a continuous microwave sludge-conditioning system.
基金Item Sponsored by National Natural Science Foundation of China(50274203)National High Technology Research and Development Program of China(2001AA337040)
文摘To design a power source system and mold for electromagnetic soft-contact continuous casting process and to theoretically estimate the heat losses from the charges and the system power, the effect of structure parameters on system power and magnetic flux density distribution was calculated using finite element method. The results show that as for electromagnetic soft-contact continuous casting system with partial-segment type mold, the power consumption is much more than that with a full-segment type mold; about 62% of electric power is dissipated in the mold, and the effective acting range of magnetic field is relatively narrow. Optimizing mold structure is a crucial measure of remarkably reducing mold power consumption and saving electric energy. Increasing slit number, width, and length can remarkably increase the magnetic flux density in the mold and can reduce the electric energy consumption. Among structure parameters, slit number and slit width are relatively more effective to reduce energy consumption. For a round billet electromagnetic continuous casting system with diameter of 178 ram, the reasonable slit number, width, and length are about 24--32, 0. 5--1.0 mm, and 160 mm, respectively.
基金Supported by the Education Foundation of Chongqing(KJ1712307)the Application Technology Research and Developments Foundation of Fuling Technology Board(FLKJ,2016ABA1026)the Young Foundation of Yangtze Normal University(2015XJXM03)
文摘Continuous homogenous azeotropic distillation(CHAD)and pressure-swing distillation(PSD)are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane.The CHAD process with acetone as the entrainer and the PSD process with the pressures of 0.1 MPa and 0.6 MPa in two columns are designed and simulated by Aspen Plus.The operating conditions of the two processes are optimized via a sequential modular approach to obtain the minimum total annual cost(TAC).The computational results show that the partially heat integrated pressure-swing distillation(HIPSD)has reduced in the energy cost and TAC by 40.79%and 35.94%,respectively,than the conventional PSD,and has more greatly reduced the energy cost and TAC by 62.61%and 49.26%respectively compared with the CHAD process.The comparison of CHAD process and partially HIPSD process illustrates that the partially HIPSD has more advantages in averting the product pollution,energy saving,and economy.
基金provided by the National Natural Science Foundation of China (51378504)Funding Project of Traffic Science and Technology Program of Hunan Province (201022)
文摘To systematically study the vehicle-bridge coupled dynamic response and its change rule with different parameters, a vehicle model with seven degrees of freedom was built and the total potential energy of vehicle space vibration system was deduced. Considering the stimulation of road roughness, the dynamic response equation of vehicle-bridge coupled system was established in accordance with the elastic system principle of total potential energy with stationary value and the ＂set-in-right-position＂ rule. On the basis of the self-compiled Fortran program and bridge engineering, the dynamic response of long- span continuous girder bridge under vehicle load was studied. This study also included the calculation of vehicle impact coefficient, evaluation of vibration comfort, and analysis of dynamic response parameters. Results show the impact coefficient changes with lane number and is larger than the value calculated by the ＂general code for design of highway bridges and culverts （China）＂. The Dieckmann index of bridge vibration is also related to lane number, and the vibration comfort evaluation is good in normal conditions. The relevant conclusions from parametric analyses have practical significance to dynamic design and daily operation of long-span continuous girder bridges in expressways. Safety and comfort are expected to improve significantly with further control of the vibration of vehicle-bridge system.
