Objectives:This study was conducted to determine the effect of multidisciplinary nursing intervention(MNI)on interdialytic weight gain(IDWG)and quality of life(QoL)among chronic hemodialysis patients.Materials and Met...Objectives:This study was conducted to determine the effect of multidisciplinary nursing intervention(MNI)on interdialytic weight gain(IDWG)and quality of life(QoL)among chronic hemodialysis patients.Materials and Methods:Quantitative research approach with randomized-controlled,single-blind trial was conducted among 120 chronic hemodialysis patients in Institute of Medical Sciences and SUM Hospital Bhubaneswar,Odisha,India from February 2023 to February 2024.Participants were randomly assigned into the experimental group(n1=65)and control group(n2=55)by block randomization methods.The experimental group received the intervention phase up to the 6th week,along with the usual treatment,and the control group received only standard treatment up to the end of the study.After that,they received the diet chart plan and fluid distribution timetable.Results:Significant improvements were found in IDWG and QoL for the experimental group.The experimental group exhibited a sharp decline in weight gain within the group(F=20.05,P<0.001)between the group(F=13.02,P<0.001),interaction effects between the groups across the time point(F=5.67,P<0.005).Kidney disease QoL scores(KDQOL^(TM)36)increased from 49.38±9.56 to 58.63±6.04 in the experimental group,compared to an increase from 50.84±9.25 to 52.04±8.02 in the control group.Conclusion:This trial showed that MNIs significantly reduced IDWG and improved KDQOL^(TM)36 scores,with the experimental group outperforming the control,highlighting the intervention’s effectiveness.展开更多
Background: Low birth weight (LBW) is a well-known factor associated with neonatal mortality and has contributed to a range of poor health outcomes. Thus, the objective of this study was to determine factors associate...Background: Low birth weight (LBW) is a well-known factor associated with neonatal mortality and has contributed to a range of poor health outcomes. Thus, the objective of this study was to determine factors associated with LBW infants. Methods: A matched case control study was conducted in Universiti Kebangsaan Malaysia. Data of deliveries were obtained from Total Hospital Information System and medical records. All registered deliveries from January to June 2012 were used as sample populations. There were 180 pairs of cases and controls matched on babies’ gender. Fourteen variables were analyzed: maternal age, ethnicity, gravida, parity, gestational age, maternal booking weight, height and body mass index (BMI), history of low birth weight infants, birth interval, booking hemoglobin levels, hypertension, diabetes mellitus and mode of delivery. Results: Younger mother (t = 6.947, p < 0.001), lower booking BMI (t = 3.067, p = 0.002), prematurity (t = 12.324, p < 0.001), history of LBW infants (OR = 3.0, p = 0.001), LSCS (OR = 0.06, p = 0.001) and current hypertension (OR = 3.1, p = 0.008) were found significant in bivariate analysis. Multivariable conditional logistic regression identified younger maternal age (AOR = 2.9, 95% CI = 1.86 -4.51, p 13.58, p = 0.045), prematurity (AOR = 2.4, 95% CI = 1.79 -3.26, p < 0.001), and current hypertension (AOR = 4.5, 95% CI = 1.06 -19.22, p = 0.041) as significant factors associated with LBW infants. Conclusion: Younger maternal age, history of LBW infants, prematurity and hypertension have been recognized as predictors of LBW infants. The importance of pre-pregnancy screening, early antenatal booking and proper identification of high risk-mother needs to be strengthened and enforced in effort to reduce incidence of LBW infants.展开更多
BACKGROUND Obesity is an important factor to cause the obstructive sleep apnea-hypopnea syndrome(OSAHS).Higher body mass index(BMI)often results in more severe OSAHS.Currently,the common measures for controlling the w...BACKGROUND Obesity is an important factor to cause the obstructive sleep apnea-hypopnea syndrome(OSAHS).Higher body mass index(BMI)often results in more severe OSAHS.Currently,the common measures for controlling the weight mainly include diet control,increase exercise and so on.Motivational interviewing(MI)could explore the patient’s internal state and make the patient realize his/her ambivalence,resulting in the change in his/her behavior.This process emphasizes respecting the patient’s autonomy.AIM To evaluate the effect of MI on the weight control of patients with OSAHS.METHODS A randomized controlled study was conducted in 100 obese OSAHS patients undergoing surgical treatment at Shengjing Hospital of China Medical University.The patients were divided into an intervention group and a control group,with 50 cases each.The control group was given routine health education after the operation;in addition to the regular health education,the intervention group was given MI according to a predetermined plan.Obesity-related indicators,postoperative complications,and the sleep status of both groups were evaluated before and 6 mo after the intervention.RESULTS Patients in the intervention group had significantly improved body weight,BMI,and waist and neck circumferences compared with patients in the control group(P<0.05).Regarding complications at 6 mo after operation,the incidence of cough and reflux in patients in the intervention group was significantly lower than that in the control group(P<0.05).In addition,the Epworth Sleepiness Scale and Self-Rating Scale of Sleep scores of patients in the intervention group were significantly lower than those in the control group,and the sleep status of patients in the intervention group was improved(P<0.05).CONCLUSION MI intervention has a significant advantage over postoperative routine health education.It can greatly change the lifestyle,further control the postoperative weight,reduce the occurrence of complications,improve the quality of sleep,and improve long-term postoperative efficacy in OSAHS patients.展开更多
Increasing attention has been attracted to the dynamic performance and safety of advanced performance predictive control systems of the next-generation aeroengine.The latest research demonstrates that Subspace-based I...Increasing attention has been attracted to the dynamic performance and safety of advanced performance predictive control systems of the next-generation aeroengine.The latest research demonstrates that Subspace-based Improved Model Predictive Control(SIMPC)can overcome the difficulty in solving the predictive model in MPC/NMPC applications.However,applying constant design parameters cannot maintain consistent control effects in all states.Meanwhile,the designed system relies too much on sensor-measured data,and thus it is difficult to thoroughly validate the safety of the system because of its high complexity.This means that any potential hardware/software faults will endanger the engine.Therefore,this paper first presents a novel nonlinear mapping relationship to adaptively tune the tracking weight online with the change of Power Lever Angle(PLA)and real-time relative tracking error.Thus,without introducing additional design parameters,an Adaptive Tracking Weight-based SIMPC(ATW-SIMPC)controller is designed to improve the control performance in all operating states effectively.Then,a Primary/Backup Hybrid Control(PBHC)strategy with the ATW-SIMPC controller as the primary system and the traditional speed(Nf)controller as the backup system is proposed to ensure safety.The designed affiliated switching controller and the real-time monitor therein can be used to realize reasonable and smooth switching between primary/backup systems,so as to avoid bump transition.The PBHC system switches to the Nf controller when the ATW-SIMPC controller is wrong because of potential hardware/software faults;otherwise,the ATW-SIMPC controller keeps acting on the engine.The main results prove that the ATW-SIMPC controller with the optimal nonlinear mapping relationship,compared with the existing SIMPC controller,uplifts the dynamic control performance by 32%and reduces overshoots to an allowable limit,resulting in a better control effect in full state.The comparison results consistently indicate that the PBHC can guarantee engine safety in occurrence of hardware/software faults,such as sensor/onboard adaptive model faults.The approach proposed is applicable to the design of a model-based engine intelligent control system.展开更多
This study presents a parametric system identification approach to estimate the dynamics of a chemical plant from experimental data and develops a robust PID controller for the plant.Parametric system identification o...This study presents a parametric system identification approach to estimate the dynamics of a chemical plant from experimental data and develops a robust PID controller for the plant.Parametric system identification of the heat exchanger system has been carried out using experimental data and prediction error method.The estimated model of the heat exchanger system is a time-delay model and a robust PID controller for the time-delayed model has been designed considering weighted sensitivity criteria.The mathematical background of parametric system identification,stability analysis,and H∞ weighted sensitivity analysis have been provided in this paper.A graphical plot has been provided to determine the stability region in the(Kp,Ki),(Kp,Kd)and(KuKd)plane.The stability region is a locus dependent on parameters of the controller and frequency,in the parameter plane.展开更多
Weighted factor is given to access eontrol policies to express the importanceof policy and its effect on access control decision. According to this weighted access controlframework, a trustworthiness model for aceess ...Weighted factor is given to access eontrol policies to express the importanceof policy and its effect on access control decision. According to this weighted access controlframework, a trustworthiness model for aceess request is also given. In this model, we give themeasure of trustworthiness factor to access request- by using some idea of uncertainty reasoning ofexpert system, present and prove the parallel propagation formula of request trustworthiness factoramong multiple policies, and get thefinal trustworthiness factor to decide whether authorizing. Inthis model, authorization decision is given according to the calculation of request trustworthinessfactor, which is more understandable, more suitable for real requirement and more powerfulforsecurity enhancement than traditional methods. Meanwhile the finer access control granularity isanother advantage.展开更多
Walking is the most basic and essential part of the activities of daily living. To enable the elderly and non-ambulatory gait-impaired patients, the repetitive practice of this task, a novel gait training robot(GTR) w...Walking is the most basic and essential part of the activities of daily living. To enable the elderly and non-ambulatory gait-impaired patients, the repetitive practice of this task, a novel gait training robot(GTR) was designed followed the end-effector principle, and an active partial body weight support(PBWS) system was introduced to facilitate successful gait training. For successful establishment of a walking gait on the GTR with PBWS, the motion laws of the GTR were planned to enable the phase distribution relationships of the cycle step, and the center of gravity(COG) trajectory of the human body during gait training on the GTR was measured. A coordinated control strategy was proposed based on the impedance control principle. A robotic prototype was developed as a platform for evaluating the design concepts and control strategies. Preliminary gait training with a healthy subject was implemented by the robotic-assisted gait training system and the experimental results are encouraging.展开更多
Currently,most teleoperation work is focusing on scenarios where slave robots interact with unknown environments.However,in some fields such as medical robots or rescue robots,the other typical teleoperation applicati...Currently,most teleoperation work is focusing on scenarios where slave robots interact with unknown environments.However,in some fields such as medical robots or rescue robots,the other typical teleoperation application is precise object transportation.Generally,the object’s weight is unknown yet essential for both accurate control of the slave robot and intuitive perception of the human operator.However,due to high cost and limited installation space,it is unreliable to employ a force sensor to directly measure the weight.Therefore,in this paper,a control scheme free of force sensor is proposed for teleoperation robots to transfer a weight-unknown object accurately.In this scheme,the workspace mapping between master and slave robot is firstly established,based on which,the operator can generate command trajectory on-line by operating the master robot.Then,a slave controller is designed to follow the master command closely and estimate the object’s weight rapidly,accurately and robust to unmodeled uncertainties.Finally,for the sake of telepresence,a master controller is designed to generate force feedback to reproduce the estimated weight of the object.In the end,comparative experiments show that the proposed scheme can achieve better control accuracy and telepresence,with accurate force feedback generated in only 500 ms.展开更多
Traditionally, basis weight control valve is driven by a constant frequency pulse signal. Therefore, it is difficult for the valve to match the control precision of basis weight. Dynamic simulation research using Matl...Traditionally, basis weight control valve is driven by a constant frequency pulse signal. Therefore, it is difficult for the valve to match the control precision of basis weight. Dynamic simulation research using Matlab/Simulink indicates that there is much more overshoot and fluctuating during the valve-positioning process. In order to improve the valve-positioning precision, the control method of trapezoidal velocity curve was studied. The simulation result showed that the positioning steady-state error was less than 0.0056%, whereas the peak error was less than 0.016% by using trapezoidal velocity curve at 10 positioning steps. A valve-positioning precision experimental device for the stepper motor of basis weight control valve was developed. The experiment results showed that the error ratio of 1/10000 positioning steps was 4% by using trapezoidal velocity curve. Furthermore, the error ratio of 10/10000 positioning steps was 0.5%. It proved that the valve-positioning precision of trapezoidal velocity curve was much higher than that of the constant frequency pulse signal control strategy. The new control method of trapezoidal velocity curve can satisfy the precision requirement of 10000 steps.展开更多
In this paper, we study the problems related to parameter estimation of a single-input and single-output networked control system, which contains possible network-induced delays and packet dropout in both of sensor-to...In this paper, we study the problems related to parameter estimation of a single-input and single-output networked control system, which contains possible network-induced delays and packet dropout in both of sensor-to-controller path and controller-to-actuator path. A weighted least squares(WLS) method is designed to estimate the parameters of plant, which could overcome the data uncertainty problem caused by delays and dropout. This WLS method is proved to be consistent and has a good asymptotic property. Simulation examples are given to validate the results.展开更多
Yaw control system plays an important role in helping large-scale horizontal wind turbines capture the wind energy.To track the stochastic and fast-changing wind direction,the nacelle is rotated by the yaw control sys...Yaw control system plays an important role in helping large-scale horizontal wind turbines capture the wind energy.To track the stochastic and fast-changing wind direction,the nacelle is rotated by the yaw control system.Therein,a difficulty consists in the variation speed of the wind direction much faster than the rotation speed of the nacelle.To deal with this difficulty,model predictive control has been recently proposed in the literature,in which the previewed wind direction is employed into the predictive model,and the estimated captured energy and yaw actuator usage are two contradictive objectives.Since the performance of the model predictive control strat-egy relies largely on the weighting factor that is designed to balance the two objectives,the weighting factor should be carefully selected.In this study,a fuzzy-deduced scheme is proposed to derive the weighting factor of the mod-el predictive yaw control.For the proposed fuzzy-deduced strategy,the variation degree and the increment of the wind direction during the predictive horizon are used as the inputs,and the weighting factor is the output,which is dynamically adjusted.The proposed model predictive yaw control is demonstrated by some simulations using real wind data and its performance is compared with the conventional model predictive control with thefixed weighting factor.Comparison results confirm the outweighing performance of the proposed control strategy over the conventional one.展开更多
Basis weight is an important indicator for evaluating paper quality and a major factor directly affecting the economic benefits of enterprises.Focusing on the large time-delay,time-varying,and nonlinear characteristic...Basis weight is an important indicator for evaluating paper quality and a major factor directly affecting the economic benefits of enterprises.Focusing on the large time-delay,time-varying,and nonlinear characteristics of a basis weight control system,a two-degree-of-freedom(TDF)internal model control(IMC)method based on a particle swarm optimization(PSO)algorithm was proposed.The method took the integral of time multiplied by the absolute error(ITAE)as the objective function,and the PSO algorithm was used to optimize the time constant of the tuning IMC filter.The simulation results for the control system under the proposed TDF-IMC method based on the PSO algorithm demonstrate good set-point tracking performance,strong anti-interference capabilities,and good robustness properties.The application results revealed that the basis weight fluctuation range of the paper was±2 g/m2,which significantly improved both the control quality and the product quality.展开更多
The basis weight control loop of the papermaking process is a non-linear system with time-delay and time-varying.It is impractical to identify a model that can restore the model of real papermaking process.Determining...The basis weight control loop of the papermaking process is a non-linear system with time-delay and time-varying.It is impractical to identify a model that can restore the model of real papermaking process.Determining a more accurate identification model is very important for designing the controller of the control system and maintaining the stable operation of the papermaking process.In this study,a strange nonchaotic particle swarm optimization(SNPSO)algorithm is proposed to identify the models of real papermaking processes,and this identification ability is significantly enhanced compared with particle swarm optimization(PSO).First,random particles are initialized by strange nonchaotic sequences to obtain high-quality solutions.Furthermore,the weight of linear attenuation is replaced by strange nonchaotic sequence and the time-varying acceleration coefficients and a mutation rule with strange nonchaotic characteristics are utilized in SNPSO.The above strategies effectively improve the global and local search ability of particles and the ability to escape from local optimization.To illustrate the effectiveness of SNPSO,step response data are used to identify the models of real industrial processes.Compared with classical PSO,PSO with timevarying acceleration coefficients(PSO-TVAC)and modified particle swarm optimization(MPSO),the simulation results demonstrate that SNPSO has stronger identification ability,faster convergence speed,and better robustness.展开更多
The sodium and glucose co-transporter inhibitors type 2 (SGLT2) comprises a new class of hypoglycemic drugs to control type 2 diabetes mellitus, in an attempt to add new non-existing benefits to the so far arising cla...The sodium and glucose co-transporter inhibitors type 2 (SGLT2) comprises a new class of hypoglycemic drugs to control type 2 diabetes mellitus, in an attempt to add new non-existing benefits to the so far arising classes. Regarding this new class of drugs, represented by dapaglifozin, canaglifozin and empaglifozin, it is important to highlight the benefits brought by these medications to combat hyperglycemia with insulin-independent mechanisms that are beyond glucose reduction, such as cardiovascular events prevention, reduction in HbA1c, weight loss and blood pressure lowering. Recently, a relevant study (Empa-Reg) brought hope and set the spotlight on the prevention of cardiac events among diabetic patients, which is the main cause of mortality within this group. However, despite coming out as a good treatment option, SGLT2 inhibitors are under constant clinical research and, as a new drug, it should be carefully carried out regarding the long-term effects of glycosuria and other possible side effects, such as the observed increase in the incidence of bladder, breast cancer and bone fractures, which require further studies. Therefore, these compounds might represent a landmark approach for the treatment of diabetes.展开更多
A PI control strategy based on fuzzy set-point weighting following was proposed for the active damping control of a hydraulic crane boom system （HCBS）. Two valve-controlled PI controllers, which include a proportion...A PI control strategy based on fuzzy set-point weighting following was proposed for the active damping control of a hydraulic crane boom system （HCBS）. Two valve-controlled PI controllers, which include a proportional feedforward controller based on fuzzy set-point weighting following and a limited semi-integrator（LSI）, are designed respectively. LSI is used to limit output signal and to prevent wind up at the low frequency of the spectrum. By using a range camera and an electronic feedback control, the tip damping on the HCBS can be adjusted artificially. A collaborative control simulation technique of HOPSAN and MATLAB/SIMULINK is applied to the controller design. Simulation results show that the proposed PI control system has less overshoot as well as faster response. The tip damping on the HCBS during operation is improved.展开更多
The paper demonstrates the possibility to enhance the damping of inter-area oscillations using Wide Area Measurement (WAM) based adaptive supervisory controller (ASC) which considers the wide-area signal transmission ...The paper demonstrates the possibility to enhance the damping of inter-area oscillations using Wide Area Measurement (WAM) based adaptive supervisory controller (ASC) which considers the wide-area signal transmission delays. The paper uses an LMI-based iterative nonlinear optimization algorithm to establish a method of designing state-feedback controllers for power systems with a time-varying delay. This method is based on the delay-dependent stabilization conditions obtained by the improved free weighting matrix (IFWM) approach. In the stabilization conditions, the upper bound of feedback signal’s transmission delays is taken into consideration. Combining theoriesof state feedback control and state observer, the ASC is designed and time-delay output feedback robust controller is realized for power system. The ASC uses the input information from Phase Measurement Units (PMUs) in the system and dispatches supplementary control signals to the available local controllers. The design of the ASC is explained in detail and its performance validated by time domain simulations on a New England test power system (NETPS).展开更多
The paper discusses the relationship between weights and control vertices of two rational NURBS curves of degree two or three with all weights larger than zero when they represent the same curve parametrically and geo...The paper discusses the relationship between weights and control vertices of two rational NURBS curves of degree two or three with all weights larger than zero when they represent the same curve parametrically and geometrically, and gives sufficient and necessary conditions for coincidence of two rational NURBS curves in non-degeneracy case.展开更多
The concept of neutrosophic statistics is applied to propose two monitoring schemes which are an improvement of the neutrosophic exponentially weighted moving average(NEWMA)chart.In this study,two control charts are d...The concept of neutrosophic statistics is applied to propose two monitoring schemes which are an improvement of the neutrosophic exponentially weighted moving average(NEWMA)chart.In this study,two control charts are designed under the uncertain environment or neutrosophic statistical interval system,when all observations are undermined,imprecise or fuzzy.These are termed neutrosophic double and triple exponentially weighted moving average(NDEWMA and NTEWMA)control charts.For the proficiency of the proposed chart,Monte Carlo simulations are used to calculate the run-length characteristics(such as average run length(ARL),standard deviation of the run length(SDRL),percentiles(P_(25),P_(50),P_(75)))of the proposed charts.The structures of the proposed control charts are more effective in detecting small shifts while these are comparable with the other existing charts in detecting moderate and large shifts.The simulation study and real-life implementations of the proposed charts show that the proposed NDEWMA and NTEWMA charts perform better in monitoring the process of road traffic crashes and electric engineering data as compared to the existing control charts.Therefore,the proposed charts will be helpful in minimizing the road accident and minimizing the defective products.Furthermore,the proposed charts are more acceptable and actual to apply in uncertain environment.展开更多
As a useful alternative of Shewhart control chart, exponentially weighted moving average （EWMA） control chat has been applied widely to quality control, process monitoring, forecast, etc. In this paper, a method was...As a useful alternative of Shewhart control chart, exponentially weighted moving average （EWMA） control chat has been applied widely to quality control, process monitoring, forecast, etc. In this paper, a method was introduced for optimal design of EWMA and multivariate EWMA （MEWMA） control charts, in which the optimal parameter pair （ λ, k） or （ λ, h ） was searched by using the generalized regression neural network （GRNN）. The results indicate that the optimal parameter pair can be obtained effectively by the proposed strategy for a given in-control average running length （ARLo） and shift to detect under any conditions, removing the drawback of incompleteness existing in the tables that had been reported.展开更多
文摘Objectives:This study was conducted to determine the effect of multidisciplinary nursing intervention(MNI)on interdialytic weight gain(IDWG)and quality of life(QoL)among chronic hemodialysis patients.Materials and Methods:Quantitative research approach with randomized-controlled,single-blind trial was conducted among 120 chronic hemodialysis patients in Institute of Medical Sciences and SUM Hospital Bhubaneswar,Odisha,India from February 2023 to February 2024.Participants were randomly assigned into the experimental group(n1=65)and control group(n2=55)by block randomization methods.The experimental group received the intervention phase up to the 6th week,along with the usual treatment,and the control group received only standard treatment up to the end of the study.After that,they received the diet chart plan and fluid distribution timetable.Results:Significant improvements were found in IDWG and QoL for the experimental group.The experimental group exhibited a sharp decline in weight gain within the group(F=20.05,P<0.001)between the group(F=13.02,P<0.001),interaction effects between the groups across the time point(F=5.67,P<0.005).Kidney disease QoL scores(KDQOL^(TM)36)increased from 49.38±9.56 to 58.63±6.04 in the experimental group,compared to an increase from 50.84±9.25 to 52.04±8.02 in the control group.Conclusion:This trial showed that MNIs significantly reduced IDWG and improved KDQOL^(TM)36 scores,with the experimental group outperforming the control,highlighting the intervention’s effectiveness.
文摘Background: Low birth weight (LBW) is a well-known factor associated with neonatal mortality and has contributed to a range of poor health outcomes. Thus, the objective of this study was to determine factors associated with LBW infants. Methods: A matched case control study was conducted in Universiti Kebangsaan Malaysia. Data of deliveries were obtained from Total Hospital Information System and medical records. All registered deliveries from January to June 2012 were used as sample populations. There were 180 pairs of cases and controls matched on babies’ gender. Fourteen variables were analyzed: maternal age, ethnicity, gravida, parity, gestational age, maternal booking weight, height and body mass index (BMI), history of low birth weight infants, birth interval, booking hemoglobin levels, hypertension, diabetes mellitus and mode of delivery. Results: Younger mother (t = 6.947, p < 0.001), lower booking BMI (t = 3.067, p = 0.002), prematurity (t = 12.324, p < 0.001), history of LBW infants (OR = 3.0, p = 0.001), LSCS (OR = 0.06, p = 0.001) and current hypertension (OR = 3.1, p = 0.008) were found significant in bivariate analysis. Multivariable conditional logistic regression identified younger maternal age (AOR = 2.9, 95% CI = 1.86 -4.51, p 13.58, p = 0.045), prematurity (AOR = 2.4, 95% CI = 1.79 -3.26, p < 0.001), and current hypertension (AOR = 4.5, 95% CI = 1.06 -19.22, p = 0.041) as significant factors associated with LBW infants. Conclusion: Younger maternal age, history of LBW infants, prematurity and hypertension have been recognized as predictors of LBW infants. The importance of pre-pregnancy screening, early antenatal booking and proper identification of high risk-mother needs to be strengthened and enforced in effort to reduce incidence of LBW infants.
基金Supported by the School of Nursing Research Project at China Medical University,No.2017HL-21.
文摘BACKGROUND Obesity is an important factor to cause the obstructive sleep apnea-hypopnea syndrome(OSAHS).Higher body mass index(BMI)often results in more severe OSAHS.Currently,the common measures for controlling the weight mainly include diet control,increase exercise and so on.Motivational interviewing(MI)could explore the patient’s internal state and make the patient realize his/her ambivalence,resulting in the change in his/her behavior.This process emphasizes respecting the patient’s autonomy.AIM To evaluate the effect of MI on the weight control of patients with OSAHS.METHODS A randomized controlled study was conducted in 100 obese OSAHS patients undergoing surgical treatment at Shengjing Hospital of China Medical University.The patients were divided into an intervention group and a control group,with 50 cases each.The control group was given routine health education after the operation;in addition to the regular health education,the intervention group was given MI according to a predetermined plan.Obesity-related indicators,postoperative complications,and the sleep status of both groups were evaluated before and 6 mo after the intervention.RESULTS Patients in the intervention group had significantly improved body weight,BMI,and waist and neck circumferences compared with patients in the control group(P<0.05).Regarding complications at 6 mo after operation,the incidence of cough and reflux in patients in the intervention group was significantly lower than that in the control group(P<0.05).In addition,the Epworth Sleepiness Scale and Self-Rating Scale of Sleep scores of patients in the intervention group were significantly lower than those in the control group,and the sleep status of patients in the intervention group was improved(P<0.05).CONCLUSION MI intervention has a significant advantage over postoperative routine health education.It can greatly change the lifestyle,further control the postoperative weight,reduce the occurrence of complications,improve the quality of sleep,and improve long-term postoperative efficacy in OSAHS patients.
基金National Natural Science Foundation of China (Nos. 52176009, 51906103) for financial support
文摘Increasing attention has been attracted to the dynamic performance and safety of advanced performance predictive control systems of the next-generation aeroengine.The latest research demonstrates that Subspace-based Improved Model Predictive Control(SIMPC)can overcome the difficulty in solving the predictive model in MPC/NMPC applications.However,applying constant design parameters cannot maintain consistent control effects in all states.Meanwhile,the designed system relies too much on sensor-measured data,and thus it is difficult to thoroughly validate the safety of the system because of its high complexity.This means that any potential hardware/software faults will endanger the engine.Therefore,this paper first presents a novel nonlinear mapping relationship to adaptively tune the tracking weight online with the change of Power Lever Angle(PLA)and real-time relative tracking error.Thus,without introducing additional design parameters,an Adaptive Tracking Weight-based SIMPC(ATW-SIMPC)controller is designed to improve the control performance in all operating states effectively.Then,a Primary/Backup Hybrid Control(PBHC)strategy with the ATW-SIMPC controller as the primary system and the traditional speed(Nf)controller as the backup system is proposed to ensure safety.The designed affiliated switching controller and the real-time monitor therein can be used to realize reasonable and smooth switching between primary/backup systems,so as to avoid bump transition.The PBHC system switches to the Nf controller when the ATW-SIMPC controller is wrong because of potential hardware/software faults;otherwise,the ATW-SIMPC controller keeps acting on the engine.The main results prove that the ATW-SIMPC controller with the optimal nonlinear mapping relationship,compared with the existing SIMPC controller,uplifts the dynamic control performance by 32%and reduces overshoots to an allowable limit,resulting in a better control effect in full state.The comparison results consistently indicate that the PBHC can guarantee engine safety in occurrence of hardware/software faults,such as sensor/onboard adaptive model faults.The approach proposed is applicable to the design of a model-based engine intelligent control system.
文摘This study presents a parametric system identification approach to estimate the dynamics of a chemical plant from experimental data and develops a robust PID controller for the plant.Parametric system identification of the heat exchanger system has been carried out using experimental data and prediction error method.The estimated model of the heat exchanger system is a time-delay model and a robust PID controller for the time-delayed model has been designed considering weighted sensitivity criteria.The mathematical background of parametric system identification,stability analysis,and H∞ weighted sensitivity analysis have been provided in this paper.A graphical plot has been provided to determine the stability region in the(Kp,Ki),(Kp,Kd)and(KuKd)plane.The stability region is a locus dependent on parameters of the controller and frequency,in the parameter plane.
文摘Weighted factor is given to access eontrol policies to express the importanceof policy and its effect on access control decision. According to this weighted access controlframework, a trustworthiness model for aceess request is also given. In this model, we give themeasure of trustworthiness factor to access request- by using some idea of uncertainty reasoning ofexpert system, present and prove the parallel propagation formula of request trustworthiness factoramong multiple policies, and get thefinal trustworthiness factor to decide whether authorizing. Inthis model, authorization decision is given according to the calculation of request trustworthinessfactor, which is more understandable, more suitable for real requirement and more powerfulforsecurity enhancement than traditional methods. Meanwhile the finer access control granularity isanother advantage.
基金Project(61175128) supported by the National Natural Science Foundation of ChinaProject(2008AA040203) supported by the National High Technology Research and Development Program of China
文摘Walking is the most basic and essential part of the activities of daily living. To enable the elderly and non-ambulatory gait-impaired patients, the repetitive practice of this task, a novel gait training robot(GTR) was designed followed the end-effector principle, and an active partial body weight support(PBWS) system was introduced to facilitate successful gait training. For successful establishment of a walking gait on the GTR with PBWS, the motion laws of the GTR were planned to enable the phase distribution relationships of the cycle step, and the center of gravity(COG) trajectory of the human body during gait training on the GTR was measured. A coordinated control strategy was proposed based on the impedance control principle. A robotic prototype was developed as a platform for evaluating the design concepts and control strategies. Preliminary gait training with a healthy subject was implemented by the robotic-assisted gait training system and the experimental results are encouraging.
基金supported in part by the National Natural Science Foundation of China(52075476,92048302)Key R&D Program of Zhejiang Province(2021C03013)。
文摘Currently,most teleoperation work is focusing on scenarios where slave robots interact with unknown environments.However,in some fields such as medical robots or rescue robots,the other typical teleoperation application is precise object transportation.Generally,the object’s weight is unknown yet essential for both accurate control of the slave robot and intuitive perception of the human operator.However,due to high cost and limited installation space,it is unreliable to employ a force sensor to directly measure the weight.Therefore,in this paper,a control scheme free of force sensor is proposed for teleoperation robots to transfer a weight-unknown object accurately.In this scheme,the workspace mapping between master and slave robot is firstly established,based on which,the operator can generate command trajectory on-line by operating the master robot.Then,a slave controller is designed to follow the master command closely and estimate the object’s weight rapidly,accurately and robust to unmodeled uncertainties.Finally,for the sake of telepresence,a master controller is designed to generate force feedback to reproduce the estimated weight of the object.In the end,comparative experiments show that the proposed scheme can achieve better control accuracy and telepresence,with accurate force feedback generated in only 500 ms.
基金supported by the International S&T Cooperation Program of China(GrantNo.2010DFB43660)National Natural Science Foundation of China(Grant No.51375286)Scientific Research Program Funded by Shaanxi Provincial Education Department(Program No.16JF005)
文摘Traditionally, basis weight control valve is driven by a constant frequency pulse signal. Therefore, it is difficult for the valve to match the control precision of basis weight. Dynamic simulation research using Matlab/Simulink indicates that there is much more overshoot and fluctuating during the valve-positioning process. In order to improve the valve-positioning precision, the control method of trapezoidal velocity curve was studied. The simulation result showed that the positioning steady-state error was less than 0.0056%, whereas the peak error was less than 0.016% by using trapezoidal velocity curve at 10 positioning steps. A valve-positioning precision experimental device for the stepper motor of basis weight control valve was developed. The experiment results showed that the error ratio of 1/10000 positioning steps was 4% by using trapezoidal velocity curve. Furthermore, the error ratio of 10/10000 positioning steps was 0.5%. It proved that the valve-positioning precision of trapezoidal velocity curve was much higher than that of the constant frequency pulse signal control strategy. The new control method of trapezoidal velocity curve can satisfy the precision requirement of 10000 steps.
基金Supported by the National Natural Science Foundation of China(61290324)
文摘In this paper, we study the problems related to parameter estimation of a single-input and single-output networked control system, which contains possible network-induced delays and packet dropout in both of sensor-to-controller path and controller-to-actuator path. A weighted least squares(WLS) method is designed to estimate the parameters of plant, which could overcome the data uncertainty problem caused by delays and dropout. This WLS method is proved to be consistent and has a good asymptotic property. Simulation examples are given to validate the results.
基金supported by the National Natural Science Foundation of China under Grant 61803393project supported by the Natural Science Foundation of Hunan Province(No.2020JJ4751)the Innovation-Driven Project of Central South University(No.2020CX031).
文摘Yaw control system plays an important role in helping large-scale horizontal wind turbines capture the wind energy.To track the stochastic and fast-changing wind direction,the nacelle is rotated by the yaw control system.Therein,a difficulty consists in the variation speed of the wind direction much faster than the rotation speed of the nacelle.To deal with this difficulty,model predictive control has been recently proposed in the literature,in which the previewed wind direction is employed into the predictive model,and the estimated captured energy and yaw actuator usage are two contradictive objectives.Since the performance of the model predictive control strat-egy relies largely on the weighting factor that is designed to balance the two objectives,the weighting factor should be carefully selected.In this study,a fuzzy-deduced scheme is proposed to derive the weighting factor of the mod-el predictive yaw control.For the proposed fuzzy-deduced strategy,the variation degree and the increment of the wind direction during the predictive horizon are used as the inputs,and the weighting factor is the output,which is dynamically adjusted.The proposed model predictive yaw control is demonstrated by some simulations using real wind data and its performance is compared with the conventional model predictive control with thefixed weighting factor.Comparison results confirm the outweighing performance of the proposed control strategy over the conventional one.
基金supported by the Shaanxi Key Innovation Team Project of Science and Technology (2014KCT-15)the Shaanxi Science & Technology Co-ordination & InnovationProject (2016KTCQ01-35)
文摘Basis weight is an important indicator for evaluating paper quality and a major factor directly affecting the economic benefits of enterprises.Focusing on the large time-delay,time-varying,and nonlinear characteristics of a basis weight control system,a two-degree-of-freedom(TDF)internal model control(IMC)method based on a particle swarm optimization(PSO)algorithm was proposed.The method took the integral of time multiplied by the absolute error(ITAE)as the objective function,and the PSO algorithm was used to optimize the time constant of the tuning IMC filter.The simulation results for the control system under the proposed TDF-IMC method based on the PSO algorithm demonstrate good set-point tracking performance,strong anti-interference capabilities,and good robustness properties.The application results revealed that the basis weight fluctuation range of the paper was±2 g/m2,which significantly improved both the control quality and the product quality.
基金support received from the National Natural Science Foundation of China(Grant No.62073206)Technical Innovation Guidance Project of Shaanxi Province(Grant No.2020CGHJ-007).
文摘The basis weight control loop of the papermaking process is a non-linear system with time-delay and time-varying.It is impractical to identify a model that can restore the model of real papermaking process.Determining a more accurate identification model is very important for designing the controller of the control system and maintaining the stable operation of the papermaking process.In this study,a strange nonchaotic particle swarm optimization(SNPSO)algorithm is proposed to identify the models of real papermaking processes,and this identification ability is significantly enhanced compared with particle swarm optimization(PSO).First,random particles are initialized by strange nonchaotic sequences to obtain high-quality solutions.Furthermore,the weight of linear attenuation is replaced by strange nonchaotic sequence and the time-varying acceleration coefficients and a mutation rule with strange nonchaotic characteristics are utilized in SNPSO.The above strategies effectively improve the global and local search ability of particles and the ability to escape from local optimization.To illustrate the effectiveness of SNPSO,step response data are used to identify the models of real industrial processes.Compared with classical PSO,PSO with timevarying acceleration coefficients(PSO-TVAC)and modified particle swarm optimization(MPSO),the simulation results demonstrate that SNPSO has stronger identification ability,faster convergence speed,and better robustness.
文摘The sodium and glucose co-transporter inhibitors type 2 (SGLT2) comprises a new class of hypoglycemic drugs to control type 2 diabetes mellitus, in an attempt to add new non-existing benefits to the so far arising classes. Regarding this new class of drugs, represented by dapaglifozin, canaglifozin and empaglifozin, it is important to highlight the benefits brought by these medications to combat hyperglycemia with insulin-independent mechanisms that are beyond glucose reduction, such as cardiovascular events prevention, reduction in HbA1c, weight loss and blood pressure lowering. Recently, a relevant study (Empa-Reg) brought hope and set the spotlight on the prevention of cardiac events among diabetic patients, which is the main cause of mortality within this group. However, despite coming out as a good treatment option, SGLT2 inhibitors are under constant clinical research and, as a new drug, it should be carefully carried out regarding the long-term effects of glycosuria and other possible side effects, such as the observed increase in the incidence of bladder, breast cancer and bone fractures, which require further studies. Therefore, these compounds might represent a landmark approach for the treatment of diabetes.
基金This work was supported by the Natural Science Foundation of Hunan Province(No.04JJ6033) and Scientific Research Fund of Hunan ProvincialEducation Department(No. 03C066).
文摘A PI control strategy based on fuzzy set-point weighting following was proposed for the active damping control of a hydraulic crane boom system （HCBS）. Two valve-controlled PI controllers, which include a proportional feedforward controller based on fuzzy set-point weighting following and a limited semi-integrator（LSI）, are designed respectively. LSI is used to limit output signal and to prevent wind up at the low frequency of the spectrum. By using a range camera and an electronic feedback control, the tip damping on the HCBS can be adjusted artificially. A collaborative control simulation technique of HOPSAN and MATLAB/SIMULINK is applied to the controller design. Simulation results show that the proposed PI control system has less overshoot as well as faster response. The tip damping on the HCBS during operation is improved.
文摘The paper demonstrates the possibility to enhance the damping of inter-area oscillations using Wide Area Measurement (WAM) based adaptive supervisory controller (ASC) which considers the wide-area signal transmission delays. The paper uses an LMI-based iterative nonlinear optimization algorithm to establish a method of designing state-feedback controllers for power systems with a time-varying delay. This method is based on the delay-dependent stabilization conditions obtained by the improved free weighting matrix (IFWM) approach. In the stabilization conditions, the upper bound of feedback signal’s transmission delays is taken into consideration. Combining theoriesof state feedback control and state observer, the ASC is designed and time-delay output feedback robust controller is realized for power system. The ASC uses the input information from Phase Measurement Units (PMUs) in the system and dispatches supplementary control signals to the available local controllers. The design of the ASC is explained in detail and its performance validated by time domain simulations on a New England test power system (NETPS).
文摘The paper discusses the relationship between weights and control vertices of two rational NURBS curves of degree two or three with all weights larger than zero when they represent the same curve parametrically and geometrically, and gives sufficient and necessary conditions for coincidence of two rational NURBS curves in non-degeneracy case.
基金This work was funded by the Deanship of Scientific Research(DSR),King Abdulaziz University,JeddahThe authors,therefore,gratefully acknowledge the DSR technical and financial support.
文摘The concept of neutrosophic statistics is applied to propose two monitoring schemes which are an improvement of the neutrosophic exponentially weighted moving average(NEWMA)chart.In this study,two control charts are designed under the uncertain environment or neutrosophic statistical interval system,when all observations are undermined,imprecise or fuzzy.These are termed neutrosophic double and triple exponentially weighted moving average(NDEWMA and NTEWMA)control charts.For the proficiency of the proposed chart,Monte Carlo simulations are used to calculate the run-length characteristics(such as average run length(ARL),standard deviation of the run length(SDRL),percentiles(P_(25),P_(50),P_(75)))of the proposed charts.The structures of the proposed control charts are more effective in detecting small shifts while these are comparable with the other existing charts in detecting moderate and large shifts.The simulation study and real-life implementations of the proposed charts show that the proposed NDEWMA and NTEWMA charts perform better in monitoring the process of road traffic crashes and electric engineering data as compared to the existing control charts.Therefore,the proposed charts will be helpful in minimizing the road accident and minimizing the defective products.Furthermore,the proposed charts are more acceptable and actual to apply in uncertain environment.
基金Funded by the National Key Technologies R&D Programs of China (No.2002BA105C)
文摘As a useful alternative of Shewhart control chart, exponentially weighted moving average （EWMA） control chat has been applied widely to quality control, process monitoring, forecast, etc. In this paper, a method was introduced for optimal design of EWMA and multivariate EWMA （MEWMA） control charts, in which the optimal parameter pair （ λ, k） or （ λ, h ） was searched by using the generalized regression neural network （GRNN）. The results indicate that the optimal parameter pair can be obtained effectively by the proposed strategy for a given in-control average running length （ARLo） and shift to detect under any conditions, removing the drawback of incompleteness existing in the tables that had been reported.
