A new method for observing steady‐state vibrations at liquid‐air interfaces

1978 ◽  
Vol 46 (2) ◽  
pp. 143-146
Author(s):  
D. M. Jacobson ◽  
B. Z. Kaplan
1993 ◽  
Vol 55 (6) ◽  
pp. 1039-1061 ◽  
Author(s):  
Vincent Gadani ◽  
Pierre Villon ◽  
Jacques Manem ◽  
Bruce Rittmann

2014 ◽  
Vol 903 ◽  
pp. 285-290 ◽  
Author(s):  
Hazriq Izzuan Jaafar ◽  
Zaharuddin Mohamed ◽  
Amar Faiz Zainal Abidin ◽  
Zamani Md Sani ◽  
Jasrul Jamani Jamian ◽  
...  

This paper presents development of an optimal PID and PD controllers for controlling the nonlinear Gantry Crane System (GCS). A new method of Binary Particle Swarm Optimization (BPSO) algorithm that uses Priority-based Fitness Scheme is developed to obtain optimal PID and PD parameters. The optimal parameters are tested on the control structure to examine system responses including trolley displacement and payload oscillation. The dynamic model of GCS is derived using Lagrange equation. Simulation is conducted within Matlab environment to verify the performance of the system in terms of settling time, steady state error and overshoot. The result not only confirmed the successes of using new method for GCS, but also shows the new method performs more efficiently compared to the continuous PSO. This proposed technique demonstrates that implementation of Priority-based Fitness Scheme in BPSO is effective and able to move the trolley as fast as possible to the desired position with low payload oscillation.


1992 ◽  
Vol 263 (2) ◽  
pp. E400-E415 ◽  
Author(s):  
A. Mari

A simple tracer-based method for calculating the rate of appearance of endogenous substances in the non-steady state, free from the inconsistencies of Steele's equation, is still lacking. This paper presents a method based on a two-compartment model by which the rate of appearance can be calculated with only a modest increase in complexity over Steele's approach. An equation is developed where the rate of appearance is expressed as a sum of three terms: a steady-state term, a term for the first compartment, and a term for the second compartment. The formula employs three parameters and makes the relationship between rate of appearance and specific activity changes explicit. An equation is also provided for estimating the error of the method in each individual run. The algorithm can be implemented with a spreadsheet on a personal computer. Simulated and experimental data obtained by the hyperinsulinemic euglycemic glucose clamp technique were used as a test. The accuracy with which the time course of glucose production could be reconstructed was clearly better than that using Steele's equation. Marked negative values for endogenous glucose output were calculated with Steele's equation but not with the new method. The characteristics of generality, simplicity, and accuracy and the availability of an error estimate make this new method suitable for routine application to non-steady-state tracer analysis.


Author(s):  
Aaron P. Wemhoff

Heating, ventilating, and air conditioning (HVAC) systems comprise nearly one third of annual household energy consumption in the United States. Energy savings can be gained by optimizing HVAC performance using a system of controls. This study applies a novel control method towards a system with an arbitrary steady-state load distribution. The new method applies multi-dimensional interpolation of optimized control configurations for various steady-state load distributions. These optimal configurations are derived using a lumped parameter simulation of the HVAC system. The new method is applied to a three-room HVAC system to demonstrate a power savings of 40% compared to an uncontrolled system. These savings compare favorably to predictions using the Variable-Air-Volume (VAV) method (37% power savings) and VAV with chiller control (33% power savings).


1995 ◽  
Vol 50 (5-6) ◽  
pp. 435-438 ◽  
Author(s):  
Alexander Borst

Abstract A new method is described which allows to image the steady-state distribution of m em ­ brane potential of single neurons in situ. The method consists of staining the tissue with an extracellular voltage-sensitive dye (Di-4-ANEPPS) and impaling a single neuron with a microelectrode. After focusing the imaging system onto the cell a large series of images are taken with a CCD camera at the appropriate excitation wavelength of the voltage-sensitive dye while the neuron’s membrane potential is shifted by a periodic current injection (PCI). Afterwards two groups of images are averaged separately: those images while the cell was at rest and those images while the cell was hyperpolarized. After subtraction of these averaged images, the resulting difference image shows only the membrane potential of the cell which was altered periodically. The success of the method is demonstrated on leech cells in intact ganglia. If applied to cells with a basically two-dimensional arborization pattern, the decrease of activity in the difference image in areas further away from the injection site should relate to a decrease in membrane potential according to the passive electrotonic properties of the cell under study.


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