A least third-order cumulants objective function

The objective of this study is to find optimum governor coefficient for which fluctuation of engine speed is minimum, for given value of engine, turbo-charger, inlet and exhaust manifold characteristics. Current study uses the Wishnegradski Stability Diagram as suggested by V. I. Krutov [1], which graphically represents the dynamic response of governor based on the engine differential equation which is of the third order. For the load type of L = B cos (wt): The objective function is designed to minimize the integral squared error over a time period T, which is taken as 5seconds. The constraints are formed using Wishnegradski Stability Curves which are mathematically represented as x > 0 and xy – 1 > 0 y > 0, where x, y are non-dimensional parameters depending on engine characteristics and Ne is the error function. From the experimental data obtained by test on a marine turbo-charged, 6 cylinder engine model KTA-1150C-600 of the Kirloskar make, the optimized values of Kp, Ki and Kd were obtained as 798.94, 41.50 and 1137.4 respectively and corresponding objective function is 2.2202e-07 and amplitude of speed fluctuation is 2.6642e-04 rpm.

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Probe size and 5th-order aberration

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125609 ◽

1987 ◽

Vol 45 ◽

pp. 134-135 ◽

Cited By ~ 1

Author(s):

Zhifeng Shao

Keyword(s):

Electron Probe ◽

Spherical Aberration ◽

Wave Length ◽

Cylindrical Symmetry ◽

Electron Wave ◽

Third Order ◽

The Third ◽

Probe Radius ◽

Small Probe ◽

Probe Size

A small electron probe has many applications in many fields and in the case of the STEM, the probe size essentially determines the ultimate resolution. However, there are many difficulties in obtaining a very small probe.Spherical aberration is one of them and all existing probe forming systems have non-zero spherical aberration. The ultimate probe radius is given byδ = 0.43Csl/4ƛ3/4where ƛ is the electron wave length and it is apparent that δ decreases only slowly with decreasing Cs. Scherzer pointed out that the third order aberration coefficient always has the same sign regardless of the field distribution, provided only that the fields have cylindrical symmetry, are independent of time and no space charge is present. To overcome this problem, he proposed a corrector consisting of octupoles and quadrupoles.

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Children’s Recall of Approximations to English

Journal of Speech and Hearing Research ◽

10.1044/jshr.1602.201 ◽

1973 ◽

Vol 16 (2) ◽

pp. 201-212 ◽

Cited By ~ 3

Author(s):

Elizabeth Carrow ◽

Michael Mauldin

Keyword(s):

Language Development ◽

Fourth Order ◽

Third Order ◽

Memory Processes ◽

The Third ◽

General Index ◽

General Linguistic

As a general index of language development, the recall of first through fourth order approximations to English was examined in four, five, six, and seven year olds and adults. Data suggested that recall improved with age, and increases in approximation to English were accompanied by increases in recall for six and seven year olds and adults. Recall improved for four and five year olds through the third order but declined at the fourth. The latter finding was attributed to deficits in semantic structures and memory processes in four and five year olds. The former finding was interpreted as an index of the development of general linguistic processes.

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