The Design of the Pilot Type Zero Steady-State Error of Water Hydraulic Overflow Valve

This paper studies on its cavitation and noise problem, according to traditional pressure controlling valve has a low accuracy of constant pressure, large leakage, poor lubrication, easy corrosion and so on, designs a new structure of pilot type of water hydraulic overflow valve based on the special physicochemical properties; Detecting the inlet pressure of the main valve with the help of the micro-pressure sensor and using closed-loop feedback control and dynamic pressure feedback control to eliminate steady-state error.

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Quantitation of the Effect of Nitrous Oxide on Rocuronium Infusion Requirements Using Closed-loop Feedback Control

Anesthesiology ◽

10.1097/aln.0b013e318164cacb ◽

2008 ◽

Vol 108 (3) ◽

pp. 388-391 ◽

Cited By ~ 6

Author(s):

Hanna Illman ◽

Heikki Antila ◽

Klaus T. Olkkola

Keyword(s):

Nitrous Oxide ◽

Steady State ◽

Feedback Control ◽

Closed Loop ◽

Neuromuscular Block ◽

Total Intravenous Anesthesia ◽

Minor Effect ◽

Intravenous Anesthesia ◽

Loop Feedback ◽

Closed Loop Feedback

Background Nitrous oxide has a minor effect on the effective dose 50% values of bolus doses of rocuronium. The authors have studied the effect of nitrous oxide on the infusion requirements of rocuronium using closed-loop feedback control of rocuronium infusion. Methods The authors obtained institutional approval and informed consent to study 70 patients. The patients were given total intravenous anesthesia with propofol and remifentanil by target-controlled infusion and were randomly assigned to one of two groups, one receiving nitrous oxide with 30% oxygen (n = 35) and the other group receiving air with 30% oxygen (n = 35). The possible interaction of rocuronium with nitrous oxide was quantitated by determining the asymptotic steady state rate of infusion of rocuronium necessary to produce a constant 90% neuromuscular block. This was accomplished by applying nonlinear curve fitting to data on the cumulative dose requirement during the initial 90-min period after bolus administration of rocuronium. Results Patient characteristics and controller performance, i.e., the ability of the controller to maintain the neuromuscular block constant at the set point, did not differ significantly between the groups. The administration of nitrous oxide did not affect rocuronium infusion requirements. The mean steady state rates of infusion were 33.0 +/- 9.8 and 36.9 +/- 13.2 mg/h in the nitrous oxide-total intravenous anesthesia and air-total intravenous anesthesia groups, respectively. Conclusions Nitrous oxide does not affect the infusion requirements of rocuronium to a clinically significant degree.

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Closed-loop feedback control of microfluidic cell manipulation via deep-learning integrated sensor networks

Lab on a Chip ◽

10.1039/d1lc00076d ◽

2021 ◽

Author(s):

Ningquan Wang ◽

Ruxiu Liu ◽

Norh Asmare ◽

Chia-Heng Chu ◽

Ozgun Civelekoglu ◽

...

Keyword(s):

Deep Learning ◽

Sensor Networks ◽

Feedback Control ◽

Closed Loop ◽

Microfluidic System ◽

Cell Manipulation ◽

Integrated Sensor ◽

Loop Feedback ◽

Closed Loop Feedback ◽

On Chip

An adaptive microfluidic system changing its operational state in real-time based on cell measurements through an on-chip electrical sensor network.

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Stability analysis in machining process by using adaptive closed-loop feedback control system in turning process

Journal of Vibration and Control ◽

10.1177/1077546320952613 ◽

2020 ◽

pp. 107754632095261

Author(s):

Kashfull Orra ◽

Sounak K Choudhury

Keyword(s):

Control System ◽

Feedback Control ◽

Closed Loop ◽

Machining Process ◽

Feedback Control System ◽

Turning Process ◽

Tool Vibration ◽

Loop Feedback ◽

Closed Loop Feedback ◽

The Stability

The study presents model-based mechanism of nonlinear cutting tool vibration in turning process and the strategy of improving cutting process stability by suppressing machine tool vibration. The approach used is based on the closed-loop feedback control system with the help of electro–magneto–rheological damper. A machine tool vibration signal generated by an accelerometer is fed back to the coil of a damper after suitable amplification. The damper, attached under the tool holder, generates counter forces to suppress the vibration after being excited by the signal in terms of current. The study also discusses the use of transfer function approach for the development of a mathematical model and adaptively controlling the process dynamics of the turning process. The purpose of developing such mechanism is to stabilize the machining process with respect to the dynamic uncut chip thickness responsible for the type-II regenerative effect. The state-space model used in this study successfully checked the adequacy of the model through controllability and observability matrices. The eigenvalue and eigenvector have confirmed the stability of the system more accurately. The characteristic of the stability lobe chart is discussed for the present model-based mechanism.

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