Optimum Nonlinear Control for Step and Pulse Disturbances

1965 ◽  
Vol 87 (1) ◽  
pp. 95-102 ◽  
Author(s):  
R. Oldenburger ◽  
R. C. C. Chang
Keyword(s):  
Control Function ◽  
Response Duration ◽  
Maximum Error ◽  
Rate Of Change ◽  
Pulse Load ◽  
Optimum Control ◽  
Controlled System ◽  
System Error ◽  
Pulse Disturbance ◽  
Advance Information

This paper treats the responses of a controlled system to step and pulse disturbances where the rate of change of the controlling variable is bounded. Optimum transients in the sense of minimizing the maximum error, response duration, and other variables are derived for step and pulse disturbances whose parameters, i.e., magnitude, sense of change, instant of occurrence and pulse duration, are either completely known in advance, or known at the instant the disturbance starts, or not known in advance at all. It is shown that the more that is known about the disturbance beforehand, the better the response that can be obtained. The improvement may be very great. The optimum control function for a pulse disturbance known at the initiation of the pulse contains disturbance parameters. A practical control function can be derived by eliminating these parameters so that no advance information about the disturbance is required. The resulting control function will yield optimum transients and will depend entirely on the system error and its derivatives. This practical control function yields improved response over classical theory to a train of pulse-load disturbances.

Doping process control in silicon epitaxy (III). Realization of optimum control function

1985 ◽  
Vol 20 (7) ◽  
pp. 943-949
Author(s):  
F. Richter ◽  
G. Kósza ◽  
R. Sperling ◽  
P. Valkó
Keyword(s):  
Process Control ◽  
Control Function ◽  
Optimum Control ◽  
Silicon Epitaxy

Graphical Determination of Optimum Trajectories for Third-Order Systems

1970 ◽  
Vol 92 (2) ◽  
pp. 271-278
Author(s):  
Yousri M. Abd-El-Fattah
Keyword(s):  
Control Function ◽  
Maximum Error ◽  
Control Signal ◽  
Graphical Solution ◽  
Third Order ◽  
Two Phase ◽  
State Trajectory ◽  
Optimum Trajectories ◽  
Initial States

The present paper explains the use of two phase planes in the graphical determination of optimum trajectories for third-order systems, depending on the sign of a single control function. The control function is defined on these planes by means of different contours. Accordingly, the control signal is known at the different points on these planes. Once the control signal is found, the state trajectory is determined. Most of the arbitrary initial states are treated and, in particular, the cases of separate steps in each of the error and its first as well as second time derivatives. This work also explains the use of the graphical solution in obtaining the maximum error and switching times.

High Altitude Observations at Sea

1951 ◽  
Vol 4 (02) ◽  
pp. 165-166
Author(s):  
A. N. Black
Keyword(s):  
High Altitude ◽  
Maximum Error ◽  
Sufficient Accuracy ◽  
Rate Of Change ◽  
Zenith Distance ◽  
The Sun ◽  
High Altitudes ◽  
Short Period ◽  
Very High

It is difficult to get satisfactory noon observations when the zenith distance is very small, because the Sun is rapidly changing in azimuth, the sextant must be swung through a wide arc of the horizon, and the Sun only dwells at the highest altitude for a very short period. To avoid these difficulties it is suggested that, instead of trying to measure the altitude of the Sun, one should measure its distance from a point on the horizon in a known azimuth. To make this measurement the Sun is brought down to the required point on the horizon, tilting the sextant as necessary; we shall distinguish this type of observation from the normal one, made with the sextant vertical, by calling the angle so obtained thehorizon distance. At normal altitudes this method, however sound in theory, breaks down because one cannot measure the azimuth with sufficient accuracy. However, at very high altitudes the rate of change of horizon distance with change of azimuth of the point from which the distance is measured becomes so small that it is not necessary to know the azimuth with such precision. In fact, at a zenith distance of 1°, the largest we shall consider here, the greatest error caused by an error of 1° in the azimuth is l″, and for smaller zenith distances the maximum error is proportionately less.

scholarly journals DECOMPOSITION OF LINEAR DISCRETE CONTROLLED SYSTEM WITH A SMALL STEP

2019 ◽  
pp. 243-248
Author(s):  
B.Y.Ashirbaev
Keyword(s):  
Control Function ◽  
Original System ◽  
Complete Separation ◽  
High Dimensionality ◽  
Equivalent System ◽  
State Variables ◽  
Small Step ◽  
Approximate Methods ◽  
Controlled System ◽  
Temporal Factors

When solving problems of optimal control of objects from various fields of science and technology, difficulties arise due to the high dimensionality of models and the presence of several temporal factors. In this regard, the problem is the decomposition of models. The paper proposes a method for decomposing a linear discrete controlled system with small steps. The equivalent system obtained with the complete separation of the state variables of a linear discrete controlled system with a small step has all the properties of the original system. It consists of two subsystems of low order, whose solutions are found independently, and they are connected only by the control function. The proposed approach combines the methods of asymptotic and approximate methods of analysis.

scholarly journals LED Driver Design with Power Optimum Control Function

2011 ◽  
Vol 60 (4) ◽  
pp. 253-256
Author(s):  
Seung-Woo Lee ◽  
Hong-Gyu Shin ◽  
Seong-Ik Cho
Keyword(s):  
Control Function ◽  
Optimum Control ◽  
Led Driver

Alcohol effect on intracranially reinforced response duration

1971 ◽  
Author(s):  
Predrag Vrtunski ◽  
Lee R. Wolin ◽  
Robert Murray
Keyword(s):  
Response Duration ◽  
Alcohol Effect

Microwave resonance method for measuring microliter volumes of free moisture in aviation fuels

2020 ◽  
pp. 49-56
Author(s):  
Vitaly V. Volkov ◽  
Michael A. Suslin ◽  
Jamil U. Dumbolov
Keyword(s):  
Solid Surface ◽  
Free Water ◽  
Resonance Method ◽  
Cavity Resonator ◽  
Maximum Error ◽  
Aviation Fuel ◽  
Fuel Quality ◽  
Microwave Resonance ◽  
Free Moisture ◽  
Microwave Losses

One of the conditions for ensuring the safety of air transport operation is the quality of aviation fuel refueled in aircraft. Fuel quality control is a multi-parameter task that includes monitoring the free moisture content. Regulatory documents establish the content of free water no more than 0.0015% by weight. It is developed a direct electrometric microwave resonance method for controlling free moisture in aviation fuels, which consists in changing the shape of the water drops by pressing them on a solid surface inside a cylindrical cavity resonator. This can dramatically increase dielectric losses. Analytical and experimental analysis of the proposed method is carried out. The control range from 0,5 to 30 μl of absolute volume of moisture in aviation fuels with a maximum error of not morethan 25 % is justified. The sensitivity of the proposed method for monitoring microwave losses in free moisture drops transformed into a thin layer by pressing is an order of magnitude greater than the sensitivity of the method for monitoring microwave losses in moisture drops on a solid surface in a resonator. The proposed method can be used as a basis for the development of devices for monitoring the free moisture of aviation fuels in the conditions of the airfield and laboratory. The direction of development of the method is shown.

Decreasing water pressure cues ‘bailout’ in seaweed-associated crustaceans

2020 ◽  
Vol 653 ◽  
pp. 121-129
Author(s):  
RB Taylor ◽  
S Patke
Keyword(s):  
Water Pressure ◽  
Rapid Change ◽  
Brown Seaweed ◽  
Model System ◽  
Rate Of Change ◽  
Suitable Habitat ◽  
Changing Light ◽  
Surface Increase ◽  
Reduced Water ◽  
Transparent Chamber

Small mobile crustaceans are abundant on seaweeds. Many of these crustaceans rapidly abandon their host if it is detached from the seafloor and floats towards the surface, but the trigger for this ‘bailout’ behaviour is unknown. We tested 2 potential cues, i.e. rapid change in light and rapid change in water pressure, using >1 mm epifauna on the brown seaweed Carpophyllum plumosum as a model system. Bailout occurred in response to reduced water pressure, but not to changing light, as (1) bailout occurred at similar rates in light and dark, (2) bailout occurred on the seafloor when water pressure was reduced within a transparent chamber by the equivalent of ~0.5 m depth or more, and (3) little bailout occurred when water pressure was held constant within the chamber while seaweeds were raised to the surface. Increase in pressure (simulating sinking) did not induce bailout. The rate of bailout increased with increasing magnitude of pressure reduction but was not influenced greatly by the rate of change of pressure within the range tested (up to an equivalent of 0.4 m depth s-1). The use of pressure rather than light as a cue for bailout is consistent with the need for seaweed-associated crustaceans to rapidly abandon a detached host and relocate to suitable habitat during both day and night.

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