期刊文献+
共找到13,788篇文章
< 1 2 250 >
每页显示 20 50 100
Integrated strategy for real-time wind power fluctuation mitigation and energy storage system control
1
作者 Yu Zhang Yongkang Zhang Tiezhou Wu 《Global Energy Interconnection》 EI CSCD 2024年第1期71-81,共11页
To address the impact of wind-power fluctuations on the stability of power systems,we propose a comprehensive approach that integrates multiple strategies and methods to enhance the efficiency and reliability of a sys... To address the impact of wind-power fluctuations on the stability of power systems,we propose a comprehensive approach that integrates multiple strategies and methods to enhance the efficiency and reliability of a system.First,we employ a strategy that restricts long-and short-term power output deviations to smoothen wind power fluctuations in real time.Second,we adopt the sliding window instantaneous complete ensemble empirical mode decomposition with adaptive noise(SW-ICEEMDAN)strategy to achieve real-time decomposition of the energy storage power,facilitating internal power distribution within the hybrid energy storage system.Finally,we introduce a rule-based multi-fuzzy control strategy for the secondary adjustment of the initial power allocation commands for different energy storage components.Through simulation validation,we demonstrate that the proposed comprehensive control strategy can smoothen wind power fluctuations in real time and decompose energy storage power.Compared with traditional empirical mode decomposition(EMD),ensemble empirical mode decomposition(EEMD),and complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN)decomposition strategies,the configuration of the energy storage system under the SW-ICEEMDAN control strategy is more optimal.Additionally,the state-of-charge of energy storage components fluctuates within a reasonable range,enhancing the stability of the power system and ensuring the secure operation of the energy storage system. 展开更多
关键词 SW-ICEEMDAN HESS real-time smoothing Rule-based multi-fuzzy control SoC
下载PDF
Base Pressure Control with Semi-Circular Ribs at Critical Mach Number
2
作者 Ambareen Khan Sher Afghan Khan +2 位作者 Mohammed Nishat Akhtar Abdul Aabid Muneer Baig 《Fluid Dynamics & Materials Processing》 EI 2024年第9期2007-2028,共22页
When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necess... When better fuel-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is activated.Controlling the base pressure and drag is necessary in both scenarios.In this work,semi-circular ribs with varying diameters(2,4,and 6 mm)positioned at six distinct positions(0.5D,1D,1.5D,2D,3D,and 4D)inside a square duct with a side of 15 mm are proposed as an efficient way to apply the passive control technique.In-depth research is done on optimising rib size for various rib sites.According to this study,the base pressure rises as rib height increases.Furthermore,the optimal location for the semi-circular ribs with a diameter of 2 mm is at 0.5D.The 1D location appears to be optimal for the 4 mm size as well.For the 6 mm size,however,the 4D position fills this function. 展开更多
关键词 Base pressure nozzle pressure ratio base drag sonic Mach number passive control
下载PDF
Screening, Treatment and Control of High Blood Pressure on Five Sites in Mali
3
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
下载PDF
Blood Pressure Profile and Glycemic Control of Type 2 Diabetics and Hypertensives at the Yalgado Ouedraogo University Hospital: A Review of 116 Cases
4
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
下载PDF
Control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method
5
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
下载PDF
Synthetic analysis of meteorological elements for the sea fogs occurred in northwest the Yellow Sea under low pressure control and comparison with sea fogs occurred under high pressure control in summer
6
作者 WANG Kaiyue MA Zheng +3 位作者 MIAO Qingsheng ZHAO Binru ZHANG Zengjian LI Cheng 《Marine Science Bulletin》 2024年第1期1-18,共18页
Based on the principle of transient perturbation analysis,in this paper,a method to objectively determine the weather pattern formed by sea fog is provided.On the basis of the classification results,the circulation si... Based on the principle of transient perturbation analysis,in this paper,a method to objectively determine the weather pattern formed by sea fog is provided.On the basis of the classification results,the circulation situation,divergence and vertical velocity field,and the vertical profile of temperature and humidity are synthesized and analyzed.The basic characteristics of the circulation and physical field of sea fog under low pressure control(L type sea fog)are obtained,and the results are compared with the sea fog under the control of high pressure(H type sea fog):a)L type sea fogs potential height anomaly disturbance is mainly manifested in the low layer,and its average value is-65.66 gpm,gradually weakening upward;b)L type sea fogs inversion structure is weaker than H type sea fogs when it occurs,the fog layer is thicker and the high relative humidity level is high over the fog layer,while the H type sea fogs fog layer has a relatively obvious dry layer;c)L sea fog has three layers of structure at the vertical direction.The first layer 1000-950 hPa is convergence accompanied by weak rise and subsidence,the second layer 950-850 hPa is divergence accompanied by weak subsidence,and the third layer 850 to 500hPa is gradually strengthened.While there are two layer structures of the H type sea fog.1000 hPa is divergence accompanied by weak rising and sinking movement,950-500 hPa is a uniform subsidence movement.d)Probability density statistical analysis further quantified the vertical movement of L and H type sea fog and the distribution of relative humidity in each layer.These conclusions provide an important reference for forecasting the sea fog in the northwest of the Yellow Sea under the condition of low pressure circulation in summer. 展开更多
关键词 sea fog under the low pressure control sea fog under the high pressure control northwest of the Yellow Sea synthetic analysis transient method
下载PDF
Preliminary Study on the Linear Relationship between the Internal Pressure Head of Rubber Dam Bags and Real-time Dam Height 被引量:1
7
作者 Yuzhi ZHI Shutao XIU 《Meteorological and Environmental Research》 CAS 2021年第5期39-41,共3页
The design operating conditions of rubber dams were analyzed,and it is found that the operating conditions are similar to the actual operating conditions of changes in the internal pressure ratio of a specific rubber ... The design operating conditions of rubber dams were analyzed,and it is found that the operating conditions are similar to the actual operating conditions of changes in the internal pressure ratio of a specific rubber dam bag in the process of filling and draining. Based on this,the linear relationship curve between the internal pressure head H0 and the real-time dam height H and its approximate analytical formula can be obtained,which can be used as a supplement and correction method for the measurement method of real-time dam height during rubber dam operation,and provides reference for rubber dam project managers. 展开更多
关键词 Rubber dam Internal pressure head real-time dam height Linear relationship
下载PDF
Real-Time Computer Analytical Application in Pressure Transient Analysis of Petroleum Reservoirs
8
作者 Kanya Khatri Sadiq A. Shah +4 位作者 Agha F. H. Pathan Bilal Shams Ashfaque A. Memon Faisal Hussain Kanwal K. Pinjani 《International Journal of Geosciences》 2013年第8期1186-1192,共7页
Today with certainty, the petroleum industry is fostering sanguinely the fields’ development programs for the optimization of reservoir characterization through worth-full appliances of computer analysis techniques. ... Today with certainty, the petroleum industry is fostering sanguinely the fields’ development programs for the optimization of reservoir characterization through worth-full appliances of computer analysis techniques. The time element is of prime importance for optimistic petroleum development projects. Therefore, the frontline of “Real-time Analysis” is added into the applications of computer solving techniques for achieving and sketching up the real-time cost effectiveness in analyzing field development programs. It focuses on the phases of real-time well test data acquisition system, real-time secure access to the well test data either on field or in office and real-time data interpretation unit. This interface will yield the productive results for the field of reservoir’s pressure transient analysis and wells’ systems analysis by following the up-to-date preferred, accurate and effective well test analytical principles with modern real-time computer applications and techniques. It also lays emphasis for the comfort and reliability of data in creating best interpersonal working modes within a reputable and esteemed petroleum development organization. 展开更多
关键词 RESERVOIR pressure Transient real-time Analysis COMFORT COMPUTER Applications
下载PDF
A Fuzzy Logic Based Supervisory Hierarchical Control Scheme for Real Time Pressure Control 被引量:6
9
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
下载PDF
Design and Experimental Evaluation of PID Controller for Digital Electro-Pneumatic Cabin Pressure Control System 被引量:3
10
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
下载PDF
Impact of Intraoperative Blood Pressure Control and Temporary Parent Artery Blocking on Prognosis in Cerebral Aneurysms Surgery 被引量:3
11
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
下载PDF
Quality control of marine big data——a case study of real-time observation station data in Qingdao 被引量:6
12
作者 QIAN Chengcheng LIU Aichao +4 位作者 HUANG Rui LIU Qingrong XU Wenkun ZHONG Shan YU Le 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第6期1983-1993,共11页
Offshore waters provide resources for human beings,while on the other hand,threaten them because of marine disasters.Ocean stations are part of offshore observation networks,and the quality of their data is of great s... Offshore waters provide resources for human beings,while on the other hand,threaten them because of marine disasters.Ocean stations are part of offshore observation networks,and the quality of their data is of great significance for exploiting and protecting the ocean.We used hourly mean wave height,temperature,and pressure real-time observation data taken in the Xiaomaidao station(in Qingdao,China)from June 1,2017,to May 31,2018,to explore the data quality using eight quality control methods,and to discriminate the most effective method for Xiaomaidao station.After using the eight quality control methods,the percentages of the mean wave height,temperature,and pressure data that passed the tests were 89.6%,88.3%,and 98.6%,respectively.With the marine disaster(wave alarm report)data,the values failed in the test mainly due to the influence of aging observation equipment and missing data transmissions.The mean wave height is often affected by dynamic marine disasters,so the continuity test method is not effective.The correlation test with other related parameters would be more useful for the mean wave height. 展开更多
关键词 quality control real-time STATION DATA MARINE BIG DATA Xiaomaidao STATION MARINE DISASTER
下载PDF
Applying real-time control to enhance the performance of nitrogen removal in CAST system 被引量:10
13
作者 WANG Shao-po PENG Yong-zhen +1 位作者 WANG Shu-ying GAO Shou-you 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第5期736-739,共4页
A bench-scale reactor(72 L) red with domestic sewage, was operated more than 3 months with three operation modes: traditional mode, modified mode and real-time control mode, so as to evaluate effects of the operati... A bench-scale reactor(72 L) red with domestic sewage, was operated more than 3 months with three operation modes: traditional mode, modified mode and real-time control mode, so as to evaluate effects of the operation mode on the system performance and to develop a feasible control strategy. Results obtained from fixed-time control study indicate that the variations of the pH and oxidation-reduction potential(ORP) profiles can represent dynamic characteristics of system and the cycle sequences can be controlled and optimized by the control points on the pH and ORP profiles. A control strategy was, therefore, developed and applied to real-time control mode. Compared with traditional mode, the total nitrogen(TN) removal can be increased by approximately 16% in modified mode and a mean TN removal of 92% was achieved in real-time control mode. Moreover, approximately 12.5% aeration energy was saved in real- time control mode. The result of this study shows that the performance of nitrogen removal was enhanced in modified operation mode. Moreover, the real-time control made it possible to optimize process operation and save aeration energy. 展开更多
关键词 cyclic activated sludge technology biological nitrogen removal real-time control oxidation-reduction potential(ORP)
下载PDF
Asymmetric Fuzzy Control of a Positive and Negative Pneumatic Pressure Servo System 被引量:2
14
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
下载PDF
Mechanism and control technology of strong ground pressure behaviour induced by high-position hard roofs in extra-thick coal seam mining 被引量:10
15
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
下载PDF
Control performance comparison between tuned liquid damper and tuned liquid column damper using real-time hybrid simulation 被引量:4
16
作者 Zhu Fei Wang Jinting +1 位作者 Jin Feng Lu Liqiao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第3期695-701,共7页
Tuned liquid damper (TLD) and tuned liquid column damper (TLCD) are two types of passive control devices that are widely used in structural control. In this study, a real-time hybrid simulation (RTHS) technique is emp... Tuned liquid damper (TLD) and tuned liquid column damper (TLCD) are two types of passive control devices that are widely used in structural control. In this study, a real-time hybrid simulation (RTHS) technique is employed to investigate the diff erence in control performance between TLD and TLCD. A series of RTHSs is presented with the premise of the same liquid length, mass ratio, and structural parameters. Herein, TLD and TLCD are physically experimented, and controlled structures are numerically simulated. Then, parametric studies are performed to further evaluate the diff erent performance between TLD and TLCD. Experimental results demonstrate that TLD is more eff ective than TLCD under diff erent amplitude excitations. 展开更多
关键词 tuned LIQUID DAMPER tuned LIQUID COLUMN DAMPER real-time hybrid simulation control effi ciency STRUCTURAL control PARAMETRIC study
下载PDF
Simulation and Experiment Research on the Proportional Pressure Control of Water-assisted Injection Molding 被引量:3
17
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
下载PDF
Intercross real-time control strategy in alternating activated sludge process for short-cut biological nitrogen removal treating domestic wastewater 被引量:4
18
作者 AKIO TAKIGAWA 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第8期957-963,共7页
To develop technically feasible and economically favorable dynamic process control(DPC)strategies for an alternating activated sludge(AAS)system,a bench-scale continuous-flow alternating aerobic and anoxic reactor,per... To develop technically feasible and economically favorable dynamic process control(DPC)strategies for an alternating activated sludge(AAS)system,a bench-scale continuous-flow alternating aerobic and anoxic reactor,performing short-cut nitrogen removal from real domestic wastewater was operated under different control strategies for more than five months.A fixed-time control(FTC) study showed that bending-points on pH and oxidation-reduction potential(ORP)profiles accurately coincided with the major biologic... 展开更多
关键词 alternating activated sludge process CONTINUOUS-FLOW real-time control NITRIFICATION
下载PDF
Validation of housekeeping genes as internal controls for studying the gene expression in Pyropia haitanensis(Bangiales, Rhodophyta) by quantitative real-time PCR 被引量:5
19
作者 LI Bing CHEN Changsheng +2 位作者 XU Yan JI Dehua XIE Chaotian 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第9期152-159,共8页
Pyropia haitanensis is an economically important mariculture crop in China and has a high research value for several life phenomena, for example environmental tolerance. To explore the mechanisms underlying these char... Pyropia haitanensis is an economically important mariculture crop in China and has a high research value for several life phenomena, for example environmental tolerance. To explore the mechanisms underlying these characteristics, gene expression has been investigated at the whole transcriptome level. Gene expression studies using quantitative real-time PCR should start by selecting an appropriate internal control gene; therefore, the absolute expression abundance of six housekeeping genes (18S rRNA (18S), ubiquitin-conju-ating enzyme (UBC), actin (ACT), β-tubulin (TUB), elongation factors 2 (EF2), and glyceraldehyde-3-phos- phate dehydrogenase (GAPDH) examined by the quantitative real-time PCR in samples corresponding to different strains, life-cycle stages and abiotic stress treatments. Their expression stabilities were assessed by the comparative cycle threshold (Ct) method and by two different software packages: geNorm and NormFinder. The most stable housekeeping gene is UBC and the least stable housekeeping is GADPH. Thus, it is proposed that the most appropriate internal control gene for expression analyses in P. haitanensis is UBC. The results pave the way for further gene expression analyses of different aspects of P. haitanensis biology including different strains, life-history stages and abiotic stress responses. 展开更多
关键词 Pyropia haitanensis quantitative real-time PCR internal control genes gene expression
下载PDF
Review of roadway control in soft surrounding rock under dynamic pressure 被引量:7
20
作者 侯朝炯 《Journal of Coal Science & Engineering(China)》 2003年第1期1-7,共7页
The basic characteristics of the soft rock roadway under the dynamic pressure are analyzed. At the same time, the three fundamental approaches for controlling the surrounding rock are proposed, which are improving the... The basic characteristics of the soft rock roadway under the dynamic pressure are analyzed. At the same time, the three fundamental approaches for controlling the surrounding rock are proposed, which are improving the surrounding rock strength, lowering the rock mass stress and selecting the reasonable supporting technology. The research results are elucidated, including the distribution of the surrounding rock plastic zone, the movement and damage of the surrounding rock under the dynamic pressure, controlling the floor heave through reinforcing the roadway walls and corners, the new route to develop the roadway metal supporting technique, the key theory and technique for the bolt supporting in the coal roadway, the performance and prospect of the ZKD high water content quick setting material, and so on. Finally, some personally views are put forward about the roadway metal supporting, bolt supporting, new material and the stress relief under the high stress condition. 展开更多
关键词 dynamic pressure roadway strata control underground pressure theory
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部