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Screening, Treatment and Control of High Blood Pressure on Five Sites in Mali
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作者 Mamadou Touré Sagara Ibrahima +19 位作者 Youssouf Camara Hamidou Oumar Bâ Ibrahima Sangaré Djénébou Traoré Noumou Sidibé Fousseyni Samassékou Massama Konaté Coumba Thiam Doumbia Asmaou Maiga Réné-Marie Dakouo Hamidou Camara Sako Mariam Sidibé Samba Adama Sogodogo Boubacar Diarra Boubacar Sonfo Aladji Traoré Mamadou Diakité Ilo Bella Diall Ichaka Menta 《World Journal of Cardiovascular Diseases》 CAS 2024年第5期322-332,共11页
Introduction: High blood pressure is defined as blood pressure greater than or equal to 140 mm Hg for systolic and or 90 mm Hg for diastolic. It constitutes a major public health problem, the leading chronic disease i... Introduction: High blood pressure is defined as blood pressure greater than or equal to 140 mm Hg for systolic and or 90 mm Hg for diastolic. It constitutes a major public health problem, the leading chronic disease in the world. The objective was to determine the prevalence, treatment rate and control of hypertension. Methods: This was a cross-sectional and descriptive study which took place over a period of 6 months in a hospital environment and in the general population. Results: Of the 1000 participants, 637 had hypertension, giving a prevalence of 63.70% with a female predominance. Thirty-three percent (33%) were unaware of their high blood pressure. The age group 60 and more was the most represented (44%). A proportion of 33 and 23.20 were overweight and obese participants, respectively. Male subjects were more overweight than female, unlike obesity which was more common among female subjects. Sixty-two percent (62%) of hypertensives were treated, of whom 44% were non-compliant. The excessively high cost and consumption of medications as needed were the main factors in therapeutic non-compliance. Twenty-two percent (22%) of all hypertensive patients and 35% of treated hypertensive patients were controlled. Women were more treated but less observant and less controlled than men. Therapeutic coverage and combination therapy rates were lower in rural areas. Hypertensives who had a high level of education were better treated and controlled than those who had no level. Conclusion: High blood pressure remains a real public health problem in Mali. It is more common in people aged 60 and over and in females. One in three hypertensives were unaware of their hypertension. The majority received antihypertensive treatments, but only a minority of them had their hypertension controlled. 展开更多
关键词 High Blood pressure SCREENING control Rate MALI
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Blood Pressure Profile and Glycemic Control of Type 2 Diabetics and Hypertensives at the Yalgado Ouedraogo University Hospital: A Review of 116 Cases
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作者 G. R. C. Millogo A. Thiam +6 位作者 Y. Kambiré E. Nongkouni S. E. Dabiré L. J. Kagambéga J. K. Kologo V. N. Yaméogo P. Zabsonré 《World Journal of Cardiovascular Diseases》 CAS 2024年第1期61-76,共16页
Objective: The association hypertension and diabetes is important. The two pathologies may influence each other. The aim was to study the correlation between glycemic control and blood pressure control and to determin... Objective: The association hypertension and diabetes is important. The two pathologies may influence each other. The aim was to study the correlation between glycemic control and blood pressure control and to determine the factors associated with blood pressure control. Methodology: This was a descriptive cross-sectional study with an analytical focus over 7 months. Patients were recruited as outpatients and all underwent ambulatory blood pressure measure, glycated hemoglobin and creatinine measurements, and assessment of compliance with treatment. Results: During this period 116 patients were collected. The predominance was female 69%. The mean age of the patients was 62 ± 7 years with a peak between 60 and 70 years. The average age of hypertension was 12 years and that of diabetes 6 1/2 years. The most frequently associated cardiovascular risk factor was a sedentary lifestyle (71.5%) after age. 57.8% of patients were not controlled at the office, with a predominance of systolic hypertension (58.2%). 61.6% of patients were controlled by ambulatory blood pressure measure, a rate of 47.8% of white coat hypertension. Glycemic control was observed in 42.2% of cases and 87% of patients had good renal function (glomerular filter rate ≥ 60 ml/mn). Therapeutic compliance was good in 53.4% of cases and dual therapy was the most used therapeutic modality 44.8% (52 patients) followed by triple therapy. The factors associated with poor blood pressure control were glycemic imbalance, non-compliance and monotherapy. Dual therapy had a protective effect. Conclusion: The association of hypertension and type 2 diabetes is frequent. The risk of occurrence increases with age. Ambulatory blood pressure measure is the best method to assess blood pressure control. Optimization of blood pressure control should also include optimization of glycemic control. 展开更多
关键词 Blood pressure control Glycemic control Hypertensive and Diabetic Patients
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Control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method
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作者 M.Hajipour G.R.Ansarifar 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期145-154,共10页
Nuclear power plants exhibit non-linear and time-variable dynamics.Therefore,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor... Nuclear power plants exhibit non-linear and time-variable dynamics.Therefore,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(SCWR)is a fourth-generation conceptual reactor.In an SCWR,the non-linear dynamics of the reactor require a controller capable of control-ling the nonlinearities.In this study,a pressure-tube-type SCWR was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled simultaneously.In an SCWR,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power maneuvering.Reactor point kinetics equations with three groups of delayed neutrons were used in the simulation.Higher-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the PI controllers speci-fied in previous studies.The controlled parameters were reactor power,steam temperature,and pressure.Notably,for these parameters,the PI controller had certain instabilities in the presence of disturbances.The classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering phenomenon.HOSMC was highly accurate and stable and had a small computational cost.In reality,it followed the desired values without oscillations and chattering. 展开更多
关键词 Supercritical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model
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In-situ pressure-preserved coring for deep exploration:Insight into the rotation behavior of the valve cover of a pressure controller 被引量:1
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作者 Da Guo He-Ping Xie +9 位作者 Ling Chen Zhong-Ya Zhou He-Ping Lu Lin Dai Ding-Ming Wang Tian-Yu Wang Ju Li Zhi-Qiang He Yun-Qi Hu Ming-Zhong Gao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2386-2398,共13页
In-situ pressure-preserved coring(IPP-Coring)is considered to be the most reliable and efficient method for the identification of the scale of oil and gas resources.During IPP-Coring,because the rotation behavior of t... In-situ pressure-preserved coring(IPP-Coring)is considered to be the most reliable and efficient method for the identification of the scale of oil and gas resources.During IPP-Coring,because the rotation behavior of the pressure controller valve cover in different medium environments is unclear,interference between the valve cover and inner pipe may occur and negatively affect the IPP-Coring success rate.To address this issue,we conducted a series of indoor experiments employing a high-speed camera to gain greater insights into the valve cover rotation behavior in different medium environments,e.g.,air,water,and simulated drilling fluids.The results indicated that the variation in the valve cover rotation angle in the air and fluid environments can be described by a one-phase exponential decay function with a constant time parameter and by biphasic dose response function,respectively.The rotation behavior in the fluid environments exhibited distinct elastic and gravitational acceleration zones.In the fluid environments,the density clearly impacted the valve cover closing time and rotation behavior,whereas the effect of viscosity was very slight.This can be attributed to the negligible influence of the fluid viscosity on the drag coefficient found in this study;meanwhile,the density can increase the buoyancy and the time period during which the valve cover experienced a high drag coefficient.Considering these results,control schemes for the valve cover rotation behavior during IPP-Coring were proposed for different layers and geological conditions in which the different drilling fluids should be used,e.g.,the use of a high-density valve cover in high-pore pressure layers. 展开更多
关键词 In-situ coring pressure coring pressure controller Rotation behavior Drilling fluid
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Effect of Home Blood Pressure Telemonitoring Plus Additional Support on Blood Pressure Control:A Randomized Clinical Trial 被引量:1
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作者 MENG Wen Wen BAI Yong Yi +6 位作者 YAN Li ZHENG Wei ZENG Qiang ZHENG Yan Song ZHA Lin PI Hong Ying SAI Xiao Yong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第6期517-526,共10页
Objective Current clinical evidence on the effects of home blood pressure telemonitoring(HBPT)on improving blood pressure control comes entirely from developed countries.Thus,we performed this randomized controlled tr... Objective Current clinical evidence on the effects of home blood pressure telemonitoring(HBPT)on improving blood pressure control comes entirely from developed countries.Thus,we performed this randomized controlled trial to evaluate whether HBPT plus support(patient education and clinician remote hypertension management)improves blood pressure control more than usual care(UC)in the Chinese population.Methods This single-center,randomized controlled study was conducted in Beijing,China.Patients aged 30-75 years were eligible for enrolment if they had blood pressure[systolic(SBP)≥140 mmHg and/or diastolic(DBP)≥90 mmHg;or SBP≥130 mmHg and/or DBP≥80 mmHg with diabetes].We recruited 190 patients randomized to either the HBPT or the UC groups for 12 weeks.The primary endpoints were blood pressure reduction and the proportion of patients achieving the target blood pressure.Results Totally,172 patients completed the study,the HBPT plus support group(n=84),and the UC group(n=88).Patients in the plus support group showed a greater reduction in mean ambulatory blood pressure than those in the UC group.The plus support group had a significantly higher proportion of patients who achieved the target blood pressure and maintained a dipper blood pressure pattern at the12th week of follow-up.Additionally,the patients in the plus support group showed lower blood pressure variability and higher drug adherence than those in the UC group.Conclusion HBPT plus additional support results in greater blood pressure reduction,better blood pressure control,a higher proportion of dipper blood pressure patterns,lower blood pressure variability,and higher drug adherence than UC.The development of telemedicine may be the cornerstone of hypertension management in primary care. 展开更多
关键词 HYPERTENSION TELEMONITORING Blood pressure control Additional support
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Clinical application of flexible ureteroscopic sheath with controllable intraluminal pressure in treating ureteral stones 被引量:1
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作者 Yuming Zhong Donghua Xie +5 位作者 Chunxiang Luo Xiaohui Liao Tairong Liu Xiaoling Deng Lunfeng Zhu Leming Song 《Asian Journal of Urology》 CSCD 2023年第2期166-171,共6页
Objective:The purpose of the study was to assess the clinical efficacy and safety of a combined perfusion suction platform with pressure feedback control function and an ureteroscopic suction sheath that can measure t... Objective:The purpose of the study was to assess the clinical efficacy and safety of a combined perfusion suction platform with pressure feedback control function and an ureteroscopic suction sheath that can measure the ureteropelvic pressure in implementing lithotripsies.Methods:Fifty-two patients who underwent lithotripsy under intelligent monitoring of ureteral intraluminal pressure from June 2016 to January 2018 were retrospectively recruited.The inclusion standard was stone diameter>1.5 cm but<2.5 cm.After the 12/14 Fr suction sheath was placed,manometer interface and suction interface of the sheath were connected to the platform via the pressure sensor and suction tube,respectively.The ureteroscope was connected to the platform perfusion pump,and the crushed stones were aspirated out under negative pressure.Results:According to the location of the stone,21(40.4%)cases were classified as upper ureteral stones,19(36.5%)were midureteral stones,and 12(23.1%)were lower ureteral stones.Forty-seven patients underwent successful primary sheath placement and lithotripsy with a mean operative time of 34.5(standard deviation 18.3)min.Retrograde stone migration did not occur.There were eight patients with hematuria postoperatively.Serious complication was 1.9% with one case of ureteral perforation.Stone clearance was 95.7% at Day 1e2 postoperatively,and 100% at Day 30 postoperatively.Conclusion:Ureteroscopic lithotripsy with intelligent pressure control using our device improved the efficiency of the lithotripsy and rate of stone clearance.The safety of the operation can be ensured.It is worth popularization and application in clinical practice. 展开更多
关键词 SUCTION URETEROSCOPY Intelligent pressure control Ureteral calculi
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Operational feasibility study of stagnation pressure reaction control for a mid-caliber non-spinning projectile
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作者 F.Bouquet 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期109-121,共13页
Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has develop... Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning projectiles.In a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test object.In an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control force.Furthermore,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering targets.This work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier study.It illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation ammunition.This research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets. 展开更多
关键词 Supersonic projectile Feasibility study Ram air Stagnation pressure reaction control Simulation Attitude control
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Pressure control method and device innovative design for deep oil in-situ exploration and coring
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作者 Nian-Han Wu Ming-Zhong Gao +5 位作者 Liang-Yu Zhu Jia-Nan Li Dong Fan Bin You Wei Luo Guo-Dong Zhu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1169-1182,共14页
Deep oil exploration coring technology cannot accurately maintain the in-situ pressure and temperature of samples, which leads to a distortion of deep oil and gas resource reserve evaluations based on conventional cor... Deep oil exploration coring technology cannot accurately maintain the in-situ pressure and temperature of samples, which leads to a distortion of deep oil and gas resource reserve evaluations based on conventional cores and cannot guide the development of deep oil and gas resources on Earth. The fundamental reason is the lack of temperature and pressure control in in-situ coring environments. In this paper, a pressure control method of a coring device is studied. The theory and method of deep intelligent temperature-pressure coupling control are innovatively proposed, and a multifield coupling dynamic sealing model is established. The optimal cardinality three term PID (Proportional-Integral-Differential) intelligent control algorithm of pressure system is developed. The temperature-pressure characteristic of the gas-liquid two-phase cavity is analyzed, and the pressure intelligent control is carried out based on three term PID control algorithms. An in-situ condition-preserved coring (ICP-Coring) device is developed, and an intelligent control system for the temperature and pressure of the coring device is designed and verified by experiments. The results show that the temperature-pressure coupling control system can effectively realize stable sealing under temperature-pressure fields of 140 MPa and 150 °C. The temperature-pressure coupling control method can accurately realize a constant pressure inside the coring device. The maximum working pressure is 140 MPa, and the effective pressure compensation range is 20 MPa. The numerical simulation experiment of pressure system control algorithm is carried out, and the optimal cardinality and three term coefficients are obtained. The pressure steady-state error is less than 0.01%. The method of temperature-pressure coupling control has guiding significance for coring device research, and is also the basis for temperature-pressure decoupling control in ICP-Coring. 展开更多
关键词 Deep oil exploration Fidelity coring device Temperature-pressure coupling control theory pressure control algorithm Temperature-pressure field alternating model
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Passive Control of Base Pressure in a Converging-Diverging Nozzle with Area Ratio 2.56 at Mach 1.8
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作者 Nur Husnina Muhamad Zuraidi Sher Afghan Khan +2 位作者 Abdul Aabid Muneer Baig Istiyaq Mudassir Shaiq 《Fluid Dynamics & Materials Processing》 EI 2023年第3期807-829,共23页
In this study,a duct is considered and special attention is paid to a passive method for the control of the base pressure relying on the use of a cavity with a variable aspect ratio.The Mach number considered is 1.8,a... In this study,a duct is considered and special attention is paid to a passive method for the control of the base pressure relying on the use of a cavity with a variable aspect ratio.The Mach number considered is 1.8,and the area ratio of the duct is 2.56.In particular,two cavities are examined,their sizes being 3:3 and 6:3.The used L/D spans the interval 1–10 while the NPRs(nozzle pressure ratio)range from 2 to 9.The results show that the control becomes effective once the nozzles are correctly expanded or under-expanded.The pressure contours at different NPR and L/D are presented.It is shown that the NPR and cavity location strongly influence the base pressure.The NPR,Mach number,and cavity aspect ratio have a strong effect on the base pressure in the wake region. 展开更多
关键词 Base pressure passive control computational fluid dynamics(CFD) SUPERSONIC AERODYNAMICS CAVITY
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Hygienic and Dietary Measures in Cameroonian Hypertensive Patients Followed at the Douala General Hospital: Knowledge, Compliance and Effect on Blood Pressure Control
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作者 Félicité Kamdem Grace Eugénie Makota Ndongo +11 位作者 Christelle Noche Domngang Hamadou Ba Jaff Fenkeu Kweban Glwadys Ngono Atéba Sidick Mouliom Henri Ngoté Lade Viché Caroline Kenmegne Marie Solange Ndom Ebongue Siddikatou Djibrilla Elysée Claude Bika Léle Samuel Kingue 《World Journal of Cardiovascular Diseases》 CAS 2023年第1期21-31,共11页
Introduction: The management of hypertension is mostly based on pharmacotherapy and hygienic and dietary measures (HDMs) for which little data is available in Cameroon. The concern to improve the quality of life of hy... Introduction: The management of hypertension is mostly based on pharmacotherapy and hygienic and dietary measures (HDMs) for which little data is available in Cameroon. The concern to improve the quality of life of hypertensive patients led us to study the knowledge, compliance and effect of HDMs among Cameroonian hypertensive patients. Methods: This was a cross-sectional study carried out at the Douala General Hospital;the census of patients was carried out from 05 March to 10 May 2018. The data evaluated were knowledge and compliance with HDMs with an inference of their effect on blood pressure control. Results: We recruited 330 participants at mean age of 60 ± 11 years, 37.9% men;57.3% with blood pressure (BP) controlled. Out of 330 subjects, 308 (93.3%) who had been educated about dietary health measures for hypertension were assessed on knowledge, compliance and effect of these measures against 22 (6.7%) who had never heard about them. Around 85.7% of participants had good knowledge of HDMs and 78.9% had good compliance with them. There was no statistically significant influence of knowledge and compliance with HDMs on blood pressure control. Conclusion: The level of knowledge and adherence to HDMs of hypertensive patients at the Douala General Hospital was appreciable. It is however appropriate for physicians to intensify patient education on HDMs and BP control. 展开更多
关键词 HYPERTENSION Hygienic and Dietary Measures Blood pressure control KNOWLEDGE COMPLIANCE
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Control of Blood Pressure and Complication Presence in Khartoum State, Sudan
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作者 Nisreen A. A. Ahmad Maha M. Bilal +4 位作者 Ziryab Z. M. Elmahdi Tayseer Abdelmotalib Ahmed Taha Tamadur A. Abdelrahman Rowa Abdelmonem Sidig Hamadto Sahar M. B. Elnour 《Open Journal of Internal Medicine》 2023年第4期381-394,共14页
Background: Hypertension is a common chronic disease and an important public health problem. The prevention of complications depends on hypertension control. Aim: To assess blood pressure control, complication presenc... Background: Hypertension is a common chronic disease and an important public health problem. The prevention of complications depends on hypertension control. Aim: To assess blood pressure control, complication presence, and their influencing factors. Methods: This cross-sectional study was conducted on patients with hypertension attending a private medical facility, a governmental facility, and a primary health care center in Khartoum, Sudan, between September 2022 and February 2023. Statistical Package for Special Sciences version 25 was used for data analysis;frequency and percentage were used to describe the qualitative variables. A chi-square test was used for co-relation analysis;a P-value ≤ 0.05 was considered statistically significant, and the confidence interval was 95%. Results: The study included 250 participants;55.6% were males. Their age was 58.77 ± 6.80 years, and they had hypertension for 10.7 ± 8.51 years. The duration of the disease was 10.7 ± 8.51 years. Systolic blood pressure was 127.1 ± 11.3 mm hg, and diastolic blood pressure was 81.6 ± 7.1 mm hg. Of the participants, 76.4% had controlled hypertension, while 27.6% had complications due to hypertension. Controlled blood pressure was associated with females, age group 40 - 60 years, normal waist circumference, and high adherence level (P ≤ 0.05). The presence of complications was associated with males, participants older than 60 years, and a low adherence level (P ≤ 0.05). Conclusions: In Sudan, the level of control is good;nonetheless, not all patients achieve it. Availability and access to treatment facilities and medications should be improved. Proper patient counseling should be offered, as well as continuous care. 展开更多
关键词 Hypertension Blood pressure control COMPLICATIONS
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Clinical Analysis of Diabetic Nephropathy Risk Factors and Correlation with Blood Pressure Control
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作者 Xing Fan Zhe Li 《Journal of Clinical and Nursing Research》 2023年第2期107-111,共5页
Objective:To explore the risk factors of diabetic nephropathy and its correlation with blood pressure control.Methods:A retrospective analysis of 80 patients with diabetic nephropathy(diabetic nephropathy group)and an... Objective:To explore the risk factors of diabetic nephropathy and its correlation with blood pressure control.Methods:A retrospective analysis of 80 patients with diabetic nephropathy(diabetic nephropathy group)and another 80 patients with diabetes(diabetic group)who were admitted to the Department of Nephrology and Endocrinology at our hospital from October 2021 to October 2022 was conducted.The general data of the two groups were compared,the influencing factors associated with the two groups were analyzed unilaterally,and unconditional dichotomous logistic regression was performed to analyze the influencing factors in patients with diabetic nephropathy.Results:There were no significant differences in high-density lipoprotein,systolic blood pressure,diastolic blood pressure,and creatinine between the two groups(P>0.05);however,compared with the diabetic group,the DN group had significantly elevated glycated hemoglobin,low-density lipoprotein,24-h urine protein,insulin resistance,and diabetes duration≥10 years(P<0.05).Conclusion:The clinical research on the correlation between the incidence of hypertension and the control of blood pressure in patients with diabetic nephropathy should be strengthened in order to formulate reasonable and feasible treatment plans. 展开更多
关键词 Diabetic nephropathy Risk factors Blood pressure control
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A Fuzzy Logic Based Supervisory Hierarchical Control Scheme for Real Time Pressure Control 被引量:6
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作者 N. Kanagaraj P. Sivashanmugam S. Paramasivam 《International Journal of Automation and computing》 EI 2009年第1期88-96,共9页
This paper describes a supervisory hierarchical fuzzy controller (SHFC) for regulating pressure in a real-time pilot pressure control system. The input scaling factor tuning of a direct expert controller is made usi... This paper describes a supervisory hierarchical fuzzy controller (SHFC) for regulating pressure in a real-time pilot pressure control system. The input scaling factor tuning of a direct expert controller is made using the error and process input parameters in a closed loop system in order to obtain better controller performance for set-point change and load disturbances. This on-line tuning method reduces operator involvement and enhances the controller performance to a wide operating range. The hierarchical control scheme consists of an intelligent upper level supervisory fuzzy controller and a lower level direct fuzzy controller. The upper level controller provides a mechanism to the main goal of the system and the lower level controller delivers the solutions to a particular situation. The control algorithm for the proposed scheme has been developed and tested using an ARM7 microcontroller-based embedded target board for a nonlinear pressure process having dead time. To demonstrate the effectiveness, the results of the proposed hierarchical controller, fuzzy controller and conventional proportional-integral (PI) controller are analyzed. The results prove that the SHFC performance is better in terms of stability and robustness than the conventional control methods. 展开更多
关键词 pressure control supervisory hierarchical fuzzy controller (SHFC) fuzzy controller ARM7 processor embedded controller
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Design and Experimental Evaluation of PID Controller for Digital Electro-Pneumatic Cabin Pressure Control System 被引量:3
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作者 Nie Jinfang Pan Quan +2 位作者 Shen Hao Song Zhitao Zhang Dalin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第5期576-583,共8页
The performance of the designed digital electro-pneumatic cabin pressure control system for the cabin pressure schedule of transport aircraft is investigated.For the purpose of this study,an experimental setup consist... The performance of the designed digital electro-pneumatic cabin pressure control system for the cabin pressure schedule of transport aircraft is investigated.For the purpose of this study,an experimental setup consisting of a simulated hermetic cabin and altitude simulation chamber is configured for cabin pressure control system operation.A series of experimental tests are executed to evaluate the performance of the cabin pressure control system.The parameters of the PID controller are optimized.In the optimization process,the variation regularity of the rate of cabin pressure change under various conditions is considered.An approach to prioritize the control of the rate of change of cabin pressure based on the flight status model is proposed and verified experimentally.The experimental results indicate that the proposed approach can be adopted for the designed digital electro-pneumatic cabin pressure control system to obtain a better cabin pressure schedule and rate of cabin pressure change. 展开更多
关键词 CABIN pressure control digital electro-pneumatic PID controller
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Impact of Intraoperative Blood Pressure Control and Temporary Parent Artery Blocking on Prognosis in Cerebral Aneurysms Surgery 被引量:3
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作者 Min Xu Zheng-song Gu +5 位作者 Cun-zu Wang Xiao-feng Lu Ding-chao Xiang Zhi-cheng Yuan Qiao-yu Li Min Wu 《Chinese Medical Sciences Journal》 CAS CSCD 2016年第2期89-94,共6页
Objective In cerebral aneurysm clipping and embolization, blood pressure control and temporaryparent artery blocking are common methods to prevent aneurysm rupture. Their influence on the prognosis isuncertain. In thi... Objective In cerebral aneurysm clipping and embolization, blood pressure control and temporaryparent artery blocking are common methods to prevent aneurysm rupture. Their influence on the prognosis isuncertain. In this study, we try to find out the association between methods above and prognostic indicators. 展开更多
关键词 cerebral ANEURYSM INTRAOPERATIVE blood pressure control PROGNOSIS TEMPORARY PARENT artery BLOCKING
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Asymmetric Fuzzy Control of a Positive and Negative Pneumatic Pressure Servo System 被引量:2
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作者 Gang Yang Jing-Min Du +1 位作者 Xiao-Yun Fu Bao-Ren Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第6期1438-1446,共9页
The pneumatic pressure control systems have been used in some fields. However, the researches on pneumatic pressure control mainly focus on constant pressure regulation. Poor dynamic characteristics and strong nonline... The pneumatic pressure control systems have been used in some fields. However, the researches on pneumatic pressure control mainly focus on constant pressure regulation. Poor dynamic characteristics and strong nonlinearity of such systems limit its application in the field of pressure tracking control. In order to meet the demand of generating dynamic pressure signal in the application of the hardware-in-the-loop simulation of aerospace engineering, a positive and negative pneumatic pressure servo system is provided to implement dynamic adjustment of sealed chamber pressure. A mathematical model is established with simulation and experiment being implemented afterwards to discuss the characteristics of the system, which shows serious asymmetry in the process of charging and discharging. Based on the analysis of the system dynamics, a fuzzy proportional integral derivative (PID) controller with asymmetric fuzzy compensator is proposed. Different from conventional adjusting mecha- nisms employing the error and change in error of the controlled variable as input parameters, the current cham- ber pressure and charging or discharging state are chosen as inputs of the compensator, which improves adaptability. To verify the effectiveness and performance of the pro- posed controller, the comparison experiments tracking sinusoidal and square wave commands are conducted. Experimental results show that the proposed controller can obtain better dynamic performance and relatively consis- tent control performance across the scope of work (2-140 kPa). The research proposes a fuzzy control method to overcome asymmetry and enhance adaptability for the positive and negative pneumatic pressure servo system. 展开更多
关键词 Pneumatic pressure control system Positiveand negative pressure Asymmetric control Fuzzy control
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Mechanism and control technology of strong ground pressure behaviour induced by high-position hard roofs in extra-thick coal seam mining 被引量:6
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作者 Chao Pan Binwei Xia +2 位作者 Yujun Zuo Bin Yu Changnan Ou 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第3期499-511,共13页
This work aimed at revealing the mechanism of strong ground pressure behaviour(SGPB)induced by high-position hard roof(HHR).Based on the supporting structures model of HHR,a modified voussoir beam mechanical model for... This work aimed at revealing the mechanism of strong ground pressure behaviour(SGPB)induced by high-position hard roof(HHR).Based on the supporting structures model of HHR,a modified voussoir beam mechanical model for HHR was established by considering the gangue support coefficient,through which the modified expressions of limit breaking span and breaking energy of HHR were deduced.Combined with the relationship between the dynamic-static loading stress of supporting body(hydraulic support and coal wall)and its comprehensive supporting strength,the criteria of ground pressure behaviour(GPB)induced by HHR were discussed.The types of Ⅰ_(1),Ⅰ_(2),Ⅱ_(1),andⅡ_(2) of GPB were interpreted.Results showed that types Ⅰ_(1) and Ⅰ_(2) were the main forms of SGPB in extra-thick coal seam mining.The main manifestation of SGPB was static stress,which was mainly derived from the instability of HHR rather than fracture.Accordingly,an innovative control technology was proposed,which can weaken static load by vertical-well separated fracturing HHR.The research results have been successfully applied to the 8101 working face in Tashan coal mine,Shanxi Province,China.The results of a digital borehole camera observation and stress monitoring proved the rationality of the GPB criteria.The control technology was successful,paving the way for new possibilities to HHR control for safety mining. 展开更多
关键词 Extra thick coal seam High-position hard roof Strong ground pressure behaviour Supporting structures Criteria of ground pressure behaviour controlling effects
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Pressure control strategy for pump motor energy transfer unit 被引量:2
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作者 姚静 Zhang Wei +2 位作者 Cao Xiaoming Zhao Guichun Sun Menghui 《High Technology Letters》 EI CAS 2019年第3期286-293,共8页
Multi-level pressure source system is a novel hydraulic system with distinct advantage of energy saving. In order to balance each pressure level of the multi-level pressure source system, a pump motor energy transfer ... Multi-level pressure source system is a novel hydraulic system with distinct advantage of energy saving. In order to balance each pressure level of the multi-level pressure source system, a pump motor energy transfer unit is usually equipped. However, the pump motor energy transfer has the characteristics of poor starting and low response, which cause long time of pressure adjustment and large pressure jitter when the transformer is switched to system suddenly and the motor-side pressure has pressure impact when rail of the pump-side is switched. To address these problems, this paper proposes a compound control strategy of feedforward compensation control with Fuzzy-PID to improve the controllability of the multi-level pressure source system. A test rig of the pump motor energy transfer unit is built and the controllability of compound controller and PID controller are compared. The experiment results show that, compared with the traditional PID, the adjustment time and the pressure impact are reduced by 20% and 25% with the proposed compound control strategy. Therefore, the presented compound control strategy can be used to improve starting performance and robustness of the pump motor energy transfer unit control system. 展开更多
关键词 HYDRAULIC system pump-motor ENERGY transfer unit pressure control ENERGY SAVING
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Experimental Study on Surface Dielectric Barrier Discharge Plasma Actuator with Different Encapsulated Electrode Widths for Airflow Control at Atmospheric Pressure 被引量:3
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作者 齐晓华 杨亮 +3 位作者 闫慧杰 金英 滑跃 任春生 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第10期1005-1011,共7页
The surface dielectric barrier discharge (SDBD) plasma actuator has shown great promise as an aerodynamic flow control device. In this paper, the encapsulated electrode width of a SDBD actuator is changed to study t... The surface dielectric barrier discharge (SDBD) plasma actuator has shown great promise as an aerodynamic flow control device. In this paper, the encapsulated electrode width of a SDBD actuator is changed to study the airflow acceleration behavior. The effects of encapsulated electrode width on the actuator performance are experimentally investigated by measuring the dielectric layer surface potential, time-averaged ionic wind velocity and thrust force. Experimental results show that the airflow velocity and thrust force increase with the encapsulated electrode width. The results can be attributed to the distinct plasma distribution at different encapsulated electrode widths. 展开更多
关键词 atmospheric pressure discharge plasma surface dielectric barrier discharge(SDBD) flow control encapsulated electrode width Schlieren visualization
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Pressure Regulation for Earth Pressure Balance Control on Shield Tunneling Machine by Using Adaptive Robust Control 被引量:7
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作者 XIE Haibo LIU Zhibin YANG Huayong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期598-606,共9页
Most current studies about shield tunneling machine focus on the construction safety and tunnel structure stability during the excavation. Behaviors of the machine itself are also studied, like some tracking control o... Most current studies about shield tunneling machine focus on the construction safety and tunnel structure stability during the excavation. Behaviors of the machine itself are also studied, like some tracking control of the machine. Yet, few works concern about the hydraulic components, especially the pressure and flow rate regulation components. This research focuses on pressure control strategies by using proportional pressure relief valve, which is widely applied on typical shield tunneling machines. Modeling of a commercial pressure relief valve is done. The modeling centers on the main valve, because the dynamic performance is determined by the main valve. To validate such modeling, a frequency-experiment result of the pressure relief valve, whose bandwidth is about 3 Hz, is presented as comparison. The modeling and the frequency experimental result show that it is reasonable to regard the pressure relief valve as a second-order system with two low corner frequencies. PID control, dead band compensation control and adaptive robust control(ARC) are proposed and simulation results are presented. For the ARC, implements by using first order approximation and second order approximation are presented. The simulation results show that the second order approximation implement with ARC can track 4 Hz sine signal very well, and the two ARC simulation errors are within 0.2 MPa. Finally, experiment results of dead band compensation control and adaptive robust control are given. The results show that dead band compensation had about 30° phase lag and about 20% off of the amplitude attenuation. ARC is tracking with little phase lag and almost no amplitude attenuation. In this research, ARC has been tested on a pressure relief valve. It is able to improve the valve's dynamic performances greatly, and it is capable of the pressure control of shield machine excavation. 展开更多
关键词 shield tunneling machine pressure regulation adaptive robust control
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