On-Line Monitoring of Fluid Effective Bulk Modulus Using Piezoelectric Transducer Impedance

2007 ◽  
Author(s):  
Gi-Woo Kim ◽  
K. W. Wang
Keyword(s):  
Bulk Modulus ◽  
Automatic Transmission ◽  
System Response ◽  
Hydraulic Control ◽  
Actuation System ◽  
Effective Bulk Modulus ◽  
System Response Time ◽  
On Line ◽  
And Performance ◽  
Entrapped Air

The fluid effective bulk modulus plays a significant role in hydraulic control systems due to its effect on the system response time and performance. In general, the fluid effective bulk modulus is a function of the amount of entrapped air, pressure, and temperature variations. Therefore, it has been recognized that monitoring of the effective bulk modulus is essential for the control of hydraulic actuation system. Measuring of the effective bulk modulus is a very challenging task. Current methods normally require precision testing equipments. Furthermore, the required equipment usually consists of many complex components that will affect the bulk modulus. Their size is in general large and thus makes on-line measurement impractical. In this research, we develop a new on-line effective bulk modulus measuring technique based upon the impedance of piezoelectric transducers. Using the piezoelectric impedance equation, numerical simulation for predicting the peak resonance frequency is performed to identify its dependency on the variation of the fluid bulk modulus. In order to verify the results, the effective bulk modulus of an ATF (automatic transmission fluid) is examined experimentally. The proposed method and the conventional method are also compared. The experimental results show the validity of the proposed method.

Parameter Estimation in a Hydrostatic System Using Extended Kalman Filter

2001 ◽  
Author(s):  
Yuvin A. Chinniah ◽  
Richard Burton ◽  
Saeid Habibi
Keyword(s):  
Kalman Filter ◽  
Bulk Modulus ◽  
Extended Kalman Filter ◽  
High Performance ◽  
State Space Model ◽  
System Response ◽  
Actuation System ◽  
Accuracy And Precision ◽  
Hydrostatic System ◽  
Entrained Air

Abstract In this paper, the Extended Kalman Filter (EKF) estimation technique is applied to a novel hydrostatic actuation system referred to as the Electrohydraulic Actuator (EHA). A state space model of the EHA is developed and the effective bulk modulus is estimated in simulation. The EHA is a high performance actuation system capable of moving large loads with very high accuracy and precision. In a practical situation, this parameter is very difficult to measure directly as it depends on entrained air which cannot be known at a particular point of time. The bulk modulus is critical for system response and a low bulk modulus as a result of air in the system can seriously hinder the performance of EHA and cause safety problems.

scholarly journals Response Time Analysis of Distributed Web Systems Using QPNs

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Tomasz Rak
Keyword(s):  
Performance Analysis ◽  
Response Time ◽  
Performance Model ◽  
Load Test ◽  
System Response ◽  
System Architectures ◽  
System Response Time ◽  
And Performance ◽  
External Loads ◽  
Web Systems

A performance model is used for studying distributed Web systems. Performance evaluation is done by obtaining load test measurements. Queueing Petri Nets formalism supports modeling and performance analysis of distributed World Wide Web environments. The proposed distributed Web systems modeling and design methodology have been applied in the evaluation of several system architectures under different external loads. Furthermore, performance analysis is done to determine the system response time.

scholarly journals The influence of chemical parameters on the in-situ metal carbonyl complex formation studied with the fast on-line reaction apparatus (FORA)

2021 ◽  
Vol 109 (4) ◽  
pp. 243-260 ◽  
Author(s):  
Yves Wittwer ◽  
Robert Eichler ◽  
Dominik Herrmann ◽  
Andreas Türler
Keyword(s):  
Metal Carbonyl ◽  
Ambient Air ◽  
Single Atom ◽  
Carbonyl Complex ◽  
Carbonyl Complexes ◽  
On Line ◽  
Carrier Gases ◽  
And Performance ◽  
Atom Chemistry

Abstract A new setup named Fast On-line Reaction Apparatus (FORA) is presented which allows for the efficient investigation and optimization of metal carbonyl complex (MCC) formation reactions under various reaction conditions. The setup contains a 252Cf-source producing short-lived Mo, Tc, Ru and Rh isotopes at a rate of a few atoms per second by its 3% spontaneous fission decay branch. Those atoms are transformed within FORA in-situ into volatile metal carbonyl complexes (MCCs) by using CO-containing carrier gases. Here, the design, operation and performance of FORA is discussed, revealing it as a suitable setup for performing single-atom chemistry studies. The influence of various gas-additives, such as CO2, CH4, H2, Ar, O2, H2O and ambient air, on the formation and transport of MCCs was investigated. O2, H2O and air were found to harm the formation and transport of MCCs in FORA, with H2O being the most severe. An exception is Tc, for which about 130 ppmv of H2O caused an increased production and transport of volatile compounds. The other gas-additives were not influencing the formation and transport efficiency of MCCs. Using an older setup called Miss Piggy based on a similar working principle as FORA, it was additionally investigated if gas-additives are mostly affecting the formation or only the transport stability of MCCs. It was found that mostly formation is impacted, as MCCs appear to be much less sensitive to reacting with gas-additives in comparison to the bare Mo, Tc, Ru and Rh atoms.

scholarly journals Interactive effects of incentive value and valence on the performance of discrete action sequences

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tyler J. Adkins ◽  
Bradley S. Gary ◽  
Taraz G. Lee
Keyword(s):  
Motor Learning ◽  
Large Body ◽  
Interactive Effects ◽  
Motor Tasks ◽  
Skill Retention ◽  
Incentive Value ◽  
Discrete Action ◽  
On Line ◽  
And Performance ◽  
Gains And Losses

AbstractIncentives can be used to increase motivation, leading to better learning and performance on skilled motor tasks. Prior work has shown that monetary punishments enhance on-line performance while equivalent monetary rewards enhance off-line skill retention. However, a large body of literature on loss aversion has shown that losses are treated as larger than equivalent gains. The divergence between the effects of punishments and reward on motor learning could be due to perceived differences in incentive value rather than valence per se. We test this hypothesis by manipulating incentive value and valence while participants trained to perform motor sequences. Consistent with our hypothesis, we found that large reward enhanced on-line performance but impaired the ability to retain the level of performance achieved during training. However, we also found that on-line performance was better with reward than punishment and that the effect of increasing incentive value was more linear with reward (small, medium, large) while the effect of value was more binary with punishment (large vs not large). These results suggest that there are differential effects of punishment and reward on motor learning and that these effects of valence are unlikely to be driven by differences in the subjective magnitude of gains and losses.

Sign in / Sign up

Export Citation Format

Share Document