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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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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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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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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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Temperature Compensation Algorithm for Hydraulic System Pressure Control 被引量:1
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作者 Huien Gao Liang Chu +1 位作者 Jianhua Guo Dianbo Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2018年第4期556-563,共8页
In this paper the control mechanism of solenoid valve is analyzed,which shows the solenoid valve control is actually the control of coil current.The response characteristic of coil current is related to coil inductanc... In this paper the control mechanism of solenoid valve is analyzed,which shows the solenoid valve control is actually the control of coil current.The response characteristic of coil current is related to coil inductance and resistance.The coil resistance is influenced greatly by the ambient temperature and the self-heating of coil,which affects the control precision of coil current.First,considering the heat dissipation mode of coil,the coil temperature model is established from the perspective of heat conduction,and a temperature compensation algorithm for hydraulic system pressure control is put forward.Then the hardware-in-the-loop testbed is set up by using the dSPACE platform,carrying out wheel cylinder pressurization tests with inlet valve fully opened at-40℃ and 20℃,and testing the actual pressure of wheel cylinder with the target pressures at-40℃ and 6 000 kPa/s(pressurization rate).The results show that the pressure control temperature compensation algorithm proposed in this paper accurately corrects the influence of resistance temperature drift on the response accuracy of wheel cylinder pressure.After the correction,the pressure difference is less than 500 kPa,which can meet the control accuracy requirements of solenoid valve,enriching the linear control characteristic of solenoid valve. 展开更多
关键词 braking energy recovery heat conduction temperature compensation linear pressure control rapid control prototype
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Automated postoperative blood pressure control 被引量:1
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作者 Hang ZHENG Kuanyi ZHU 《控制理论与应用(英文版)》 EI 2005年第3期207-212,共6页
It is very important to maintain the level of mean arterial pressure (MAP). The MAP control is applied in many clinical situations, including limiting bleeding during cardiac surgery and promoting healing for patien... It is very important to maintain the level of mean arterial pressure (MAP). The MAP control is applied in many clinical situations, including limiting bleeding during cardiac surgery and promoting healing for patient' s post-surgery. This paper presents a fuzzy controller-based multiple-model adaptive control system for postoperative blood pressure management. Multiple-model adaptive control (MMAC) algorithm is used to identify the patient model, and it is a feasible system identification method even in the presence of large noise. Fuzzy control (FC) method is used to design controller bank. Each fuzzy controller in the controller bank is in fact a nonlinear proportional-integral (PI) controller,whose proportional gain and integral gain are adjusted continuously according to error and rate of change of error of the plant output, resulting in better dynamic and stable control performance than the regular PI controller, especially when a nonlinear process is involved. For demonstration, a nonlinear, pulsatile-flow patient model is used for simulation, and the results show that the adaptive control system can effectively handle the changes in patient's dynamics and provide satisfactory performance in regulation of blood pressure of hypertension patients. 展开更多
关键词 Multiple-model adaptive control Fuzzy control Blood pressure control Cardiovascular modeling
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Simulation and Experiment Research on the Proportional Pressure Control of Water-assisted Injection Molding 被引量:3
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作者 ZHOU Hua CHEN Yinglong +1 位作者 ZHANG Zengmeng YANG Huayong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第3期430-438,共9页
Water-assisted injection molding(WAIM),a newly developed fluid-assisted injection molding technology has drawn more and more attentions for the energy saving,short cooling circle time and high quality of products.Ex... Water-assisted injection molding(WAIM),a newly developed fluid-assisted injection molding technology has drawn more and more attentions for the energy saving,short cooling circle time and high quality of products.Existing research for the process of WAIM has shown that the pressure control of the injecting water is mostly important for the WAIM.However,the proportional pressure control for the WAIM system is quite complex due to the existence of nonlinearities in the water hydraulic system.In order to achieve better pressure control performance of the injecting water to meet the requirements of the WAIM,the proportional pressure control of the WAIM system is investigated both numerically and experimentally.A newly designed water hydraulic system for WAIM is first modeled in AMEsim environment,the load characteristics and the nonlinearities of water hydraulic system are both considered,then the main factors affecting the injecting pressure and load flow rate are extensively studied.Meanwhile,an open-loop model-based compensation control strategy is employed to regulate the water injection pressure and a feedback proportional integrator controller is further adopted to achieve better control performance.In order to verify the AMEsim simulation results WAIM experiment for particular Acrylonitrile Butadiene Styrene(ABS) parts is implemented and the measured experimental data including injecting pressure and flow rate results are compared with the simulation.The good coincidence between experiment and simulation shows that the AMEsim model is accurate,and the tracking performance of the load pressure indicates that the proposed control strategy is effective for the proportional pressure control of the nonlinear WAIM system.The proposed proportional pressure control strategy and the conclusions drawn from simulation and experiment contribute to the application of water hydraulic proportional control and WAIM technology. 展开更多
关键词 water-assisted injection molding nonlinear modeling proportional pressure control AMEsim simulation
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Numerical study of biomechanical characteristics of plaque rupture at stenosed carotid bifurcation:a stenosis mechanical property-specific guide for blood pressure control in daily activities
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作者 Shaoxiong Yang Qinghu Wang +3 位作者 Weihao Shi Wencheng Guo Zonglai Jiang Xiaobo Gong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第6期1279-1289,共11页
Acute stress concentration plays an important role in plaque rupture and may cause stroke or myocardial infarction.Quantitative evaluation of the relation between in vivo plaque stress and variations in blood pressure... Acute stress concentration plays an important role in plaque rupture and may cause stroke or myocardial infarction.Quantitative evaluation of the relation between in vivo plaque stress and variations in blood pressure and flow rates is valuable to optimize daily monitoring of the cardiovascular system for high-risk patients as well as to set a safe physical exercise intensity for better quality of life.In this study,we constructed an in vivo stress model for a human carotid bifurcation with atherosclerotic plaque,and analyzed the effects of blood pressure,flow rates,plaque stiffness,and stenosis on the elastic stress and fluid viscous stress around the plaque.According to the maximum values of the mechanical stress,we define a risk index to predict the risk level of plaque rupture under different exercise intensities.For a carotid bifurcation where the blood flow divides,the results suggest that the stenosis ratio determines the ratio of the contributions of elastic shear stress and viscous shear stress to plaque rupture.A n increase of the plaque stiffness enhances the maximum elastic shear stress in the plaque,indicating that a high-stiffness plaque is more prone to rupture for given stenosis ratio.High stress co-localization at the shoulder of plaques agrees with the region of plaque injury in clinical observations.It is demonstrated that,due to the stress-shield effect,the rupture risk of a high-stiffness plaque tends to decrease under high-stenosis conditions,suggesting the existence of a specific stenosis corresponding to the maximum risk.This study may help to complement risk stratification of vulnerable plaques in clinical practice and provides a stenosis mechanical property-specific guide for blood pressure control in cardiovascular health management. 展开更多
关键词 Stenosed carotid bifurcation In vivo stress Plaque rupture Risk stratification Blood pressure control
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Experimental confirmation of physical metal penetration generation and press casting production considering molten metal's pressure control
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作者 Ryosuke Tasaki Yoshiyuki Noda +1 位作者 Kunihiro Hashimoto Kazuhiko Terashima 《China Foundry》 SCIE CAS 2012年第1期84-90,共7页
This paper presents a technique for controlling the pressure of a molten metal when using a new type of iron casting method called sand mold press casting to realize high productivity and obtain high-quality products.... This paper presents a technique for controlling the pressure of a molten metal when using a new type of iron casting method called sand mold press casting to realize high productivity and obtain high-quality products.The past test results using this method showed a casting yield of 90% to 95%,while conventional methods only show a casting yield of 60% to 70%.Although the press casting method does not require a sprue cup or runner channel casting defects such as metal penetration are often caused by the high pressure in the high-velocity pressing part of this casting process.Therefore,we proposed a pressure control method with a mathematical model of molten metal pressure,and with it we achieved experimental confirmation of the successful production of brake drums at different pressing temperatures.Results show that the proposed pressing control method can realize sound,penetration-free casting production.However,the theoretical analysis and design of this pressing process had not previously been studied sufficiently,and therefore this paper presents the theoretical design algorithm for the process as well as its experimental confirmation. 展开更多
关键词 press casting pressure control metal penetration sand mould
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Pressure control of PEMFC distributed power generator
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作者 张颖颖 曹广益 朱新坚 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期262-267,共6页
Control design is important for PEMFC (proton exchange membrane fuel cell) distributed power generator to satisfy user requirement for safe and stable operation. For a complex multi-variable dynamic system, a dynami... Control design is important for PEMFC (proton exchange membrane fuel cell) distributed power generator to satisfy user requirement for safe and stable operation. For a complex multi-variable dynamic system, a dynamic simulation model is first established. In view of close coupling and non-linear relationships between variables, the intelligent auto-adapted PI decoupling control method is used. From the simulation results it is found that, by bringing quadratic performance index in the single neuron, constructing adaptive PI controller, and adjusting gas flow rates through the second pressure relief valve and air compressor coordinately, both anode and cathode pressures can be maintained at ideal levels. 展开更多
关键词 proton exchange membrane fuel cell (PEMFC) distributed power generator pressure control flow rate PI decoupling control quadratic performance index single neuron adaptive PI controller.
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Model Based Pressure Control of a Push Belt Continuously Variable Transmission
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作者 Bashar Alzuwayer Aviral Singh +1 位作者 Prasanth Muralidharan Zhijun Han 《Modern Mechanical Engineering》 2016年第4期99-112,共14页
A Continuously Variable Transmission (CVT) is a type of transmissions that provides a continuous range of speed ratios, thus it allows increasing the overall powertrain efficiency by running the engine at the optimal ... A Continuously Variable Transmission (CVT) is a type of transmissions that provides a continuous range of speed ratios, thus it allows increasing the overall powertrain efficiency by running the engine at the optimal operating points. This paper investigates implementing a model based hydraulic pressure controller to achieve the desired CVT gear ratio. A map of desired gear ratios was estimated using the Optimal Operating Line (OOL) strategy, which minimizes the engine fuel consumption according to a defined cost function and a set of systems constraints. The controller was implemented in a complete vehicle model that includes driver, powertrain and road load models. The model was subjected to two different driving cycles and the results demonstrate the effectiveness of the control strategy and the pressure controller in keeping the engine at the most efficient operating regions. 展开更多
关键词 CVT pressure control Optimal Operating Line Metal Push-Belt
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Rotational failure analysis of spherical-cylindrical shell pressure controllers related to gas hydrate drilling investigations 被引量:2
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作者 Cong Li Jian-Liang Pei +6 位作者 Nian-Han Wu Gui-Kang Liu Wei Huang Zhi-Xu Dai Rui-Ze Wang Zhao-Fan Chen Wei-Cheng Long 《Petroleum Science》 SCIE CAS CSCD 2022年第2期789-799,共11页
In situ pressure-preserved coring(IPP-Coring)technology is considered one of the most efficient methods for assessing resources.However,seal failure caused by the rotation of pressure controllers greatly affects the s... In situ pressure-preserved coring(IPP-Coring)technology is considered one of the most efficient methods for assessing resources.However,seal failure caused by the rotation of pressure controllers greatly affects the success of pressure coring.In this paper,a novel spherical-cylindrical shell pressure controller was proposed.The finite element analysis model was used to analyze the stress distribution and deformation characteristics of the pressure controller at different rotation angles.The seal failure mechanism caused by the rotation of the pressure controller was discussed.The stress deviation rate was defined to quantitatively characterize the stress concentration.Based on the test equipment designed in this laboratory,the ultimate bearing strength of the pressure controller was tested.The results show that the rotation of the valve cover causes an increase in the deformation on its lower side.Furthermore,the specific sealing pressure in the weak zone is greatly reduced by a statistically significant amount,resulting in seal failure.When the valve cover rotates 5°around the major axis,the stress deviation rate is-92.6%.To prevent rotating failure of the pressure controller,it is necessary to control the rotation angle of the valve cover within 1°around the major axis.The results of this research can help engineers reduce failure-related accidents,provide countermeasures for pressure coring,and contribute to the exploration and evaluation of deep oil and gas resources. 展开更多
关键词 Exploration of oil and gas resources pressure coring controller Sphere flapper valve Failure modes Stress deviation rate
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Home Blood Pressure Monitoring and Its Association With Blood Pressure Control Among Hypertensive Patients With High Cardiovascular Risk in China
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作者 Jiaying Li Aoxi Tian +4 位作者 Jiamin Liu Jinzhuo Ge Yue Peng Xiaoming Su Jing Li 《Cardiology Discovery》 2024年第1期15-22,共8页
Objective:Home blood pressure monitoring(HBPM)is viewed as a facilitating factor in the initial diagnosis and long-term management of treated hypertension.However,evidence remains scarce about the effectiveness of HBP... Objective:Home blood pressure monitoring(HBPM)is viewed as a facilitating factor in the initial diagnosis and long-term management of treated hypertension.However,evidence remains scarce about the effectiveness of HBPM use in the real world.This study aimed to examine the associations of HBPM use with blood pressure(BP)control and medication adherence.Methods:This prospective cohort study included hypertensive patients with high cardiovascular risk who were aged≥50 years.At baseline,information about types of BP monitor,frequency of HBPM,perception of anti-hypertensive treatment,and measured office BP were collected.During the 1-year follow-up(visits at 1,2,3,6,and 12 months),information on medication adherence was collected at each visit.The 2 major outcomes were BP control at baseline and medication adherence during the 1-year follow-up.A log-binomial regression model was used to examine the association between frequency of HBPM and outcomes,stratified by the perceptions of anti-hypertensive treatment.Results:A total of 5,363 hypertensive patients were included in the analysis.The age was(64.6±7.2)years,and 41.2%(2,208)were female.Of the total patients,85.9%(4,606)had a home BP monitor and 47.8%(2,564)had an incorrect perception of anti-hypertensive treatment.Overall,24.2%(1,299)of patients monitored their BP daily,37.6%(2,015)weekly,17.3%(926)monthly,and 20.9%(1,123)less than monthly.At baseline,the systolic BP and diastolic BP were(146.6±10.8)mmHg and(81.9±10.6)mmHg,respectively,and 28.5%(1,527)of patients had their BP controlled.Regardless of whether the patients had correct or incorrect perceptions of anti-hypertensive treatment,there is no significant association between HBPM frequency and BP control at baseline.During the 1-year follow-up,23.9%(1,280)of patients had non-adherence to medications at least once.In patients with an incorrect perception of anti-hypertensive treatment,those monitoring BP most frequently(daily)had the highest non-adherence rate(29.9%,175/585).Compared with those monitoring their BP less than monthly,patients who monitored their BP daily were more likely not to adhere to anti-hypertensive medications(adjusted relative risk=1.38,95%confidence interval:1.11–1.72,P=0.004).Conclusions:HBPM performance among hypertensive patients in China is,in general,sub-optimal.No association was observed between using HBPM alone and hypertension control,indicating that the effects of HBPM could be conditional.Patients’misconceptions about anti-hypertensive treatment may impair the role of BP monitoring in achieving medication adherence.Fully incorporating the correct perception of hypertension into the management of hypertensive patients is needed. 展开更多
关键词 HYPERTENSION Home blood pressure monitoring Blood pressure control Medication adherence
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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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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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Design and experiment of the pneumatic pressure control device for no-till planter
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作者 Xinpeng Cao Qingjie Wang +4 位作者 Hongwen Li Jin He Caiyun Lu Dijuan Xu Xiuhong Wang 《International Journal of Agricultural and Biological Engineering》 SCIE 2023年第3期37-46,共10页
An adequate and uniform press wheel pressure is crucial for the homogeneous development of a crop,as it affects actual seeding depth and germination rate.The problems of uneven compaction of seed furrow and consistenc... An adequate and uniform press wheel pressure is crucial for the homogeneous development of a crop,as it affects actual seeding depth and germination rate.The problems of uneven compaction of seed furrow and consistency of seeding depth can be caused by the pressure fluctuation of the coil-spring pressure control device(CPCD)when the no-till planter is working on the unplowed ground.In this study,a pneumatic pressure control device(PPCD)was designed for the no-till planter,the key structural parameters of air spring for press wheel pressure(PWP)stability were determined by theoretical analysis and parameter calculation.Using the gas-structure coupling finite element simulation method(FESM),the piston radius,piston angle,and cord angle of the air spring are selected as the test factors,and the vertical stiffness was used as the test index to carry out the quadratic rotation orthogonal combination test to establish the regression model of test index and factor.The bench test of the PPCD was carried out under the optimal parameter combination,piston radius of 27.2 mm,piston angle of 11.7°,and cord angle of 30.0°.The vertical stiffness verification test showed that the simulation test was consistent with the bench test result,the vertical stiffness simulation error was 7.1%,and the internal air pressure simulation error was 3.0%;The control response test showed that the average response time of the air spring inflating and deflating was 0.80 s,the maximum overshoot was 4.33%during inflation,and no pressure overshoot during deflation;Under the condition of-40-40 mm surface relief height,the PPCD could effectively reduce the pressure fluctuation compared with the CPCD,and the average reduction of the pressure fluctuation was about 25.1%. 展开更多
关键词 air spring no-till planter pressure control finite element analysis
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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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