Tuning of PID controllers based on gain and phase margin specifications

A method of evaluating the performance of a control system using a computerized device includes calculating a ratio of a first area and a second area associated with a peak value of a signal associated with the control system, comparing the ratio with a predetermined value for the ratio, determining a cause of oscillation in the control system based on the comparison of the ratio with the predetermined value for the ratio, and providing a diagnosis of the cause of oscillation in the control system.

Method of and apparatus for evaluating the performance of a control system

We report a method for the synthesis of N-protected staurosporinones, which are useful for the synthesis of indolo[2,3-a]pyrrolo[3,4-c]carbazole alkaloids and related compounds. An interaction of gramine methiodide (2) with 3-(N-benzyl)indolylacetonitrile (3) in the presence of t-BuLi, followed by a CF3COOH-catalyzed intramolecular indole−indole coupling and dehydrogenation with DDQ, produced 5-cyanoindolo[2,3-a]carbazole 6 almost quantitatively. Reduction of its cyano group followed by N-benzylation produced N-benzylaminomethylindolo[2,3-a]carbazole 8b, which was subjected to Pd(OAc)2-catalyzed direct aromatic carbonylation to give N-protected staurosporinone 9b. Treatment with AlCl3 in anisole removed N-benzyl groups to afford staurosporinone quantitatively.

Synthesis of N-protected staurosporinones.

Polypyrimidine . polypurine segments are regions of duplex DNA which contain a highly asymmetric distribution of pyrimidine and purine nucleotides. A polypyrimidine in single-stranded DNA can be detected by its ability to form a complex and poly(A, G) which will bind to hydroxyapatite. We tested DNA from a variety of organisms and found that most contained polypyrimidines. From the shape of the curve relating DNA size to percentage bound to hydroxyapatite, we conclude that polypyrimidine . polypurine segments occur widely in DNA from higher organisms, at intervals of 6000--8000 base pairs throughout the majority of the genome. Lower levels occur in DNA from yeast and Drosophila.

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1432-1033.1979.tb13189.x

Distribution of Polypyrimidine · Polypurine Segments in DNA from Diverse Organisms

Insulin injection therapy is widely practiced for the maintenance of blood glucose levels within the normoglycemic range (70−100 mg/dL) for type I diabetics Several proportional−integral−derivativ

Robust PID controller for blood glucose regulation in type I diabetics

Four methods are proposed for estimating the dominant time constant and dead time of a given process from a knowledge of its moments, s-plane, frequency or transient response data. The methods are faster and simpler and, in terms of accuracy and reliabiltiy, are comparable to the time domain least squares procedure for parameter estimation. Applications of the methods are illustrated with the aid of a dispersion model. A comparison is also made with other known techniques to demonstrate the superiority of the suggested methods.

Estimation of time delay time constant parameters in time, frequency, and laplace domains

The dispersion coefficient, the time delay and the time constant, as parameters associated with models of liquid phase axial dispersion in fluidized systems, have been correlated using available literature data for fluidization involving a wide range of fluid and particle properties. The results permit prediction of these parameters from only a knowledge of the bed voidage. A comparison with Chung and Wen's1 correlation demonstrates the superiority of the present correlation.



On a etabli une correlation impliquant le coefficient de dispersion, le retard et la constante de temps comme parametres associes a des moddeles de dispersion axiale en phase liquide dans des systemes fluidise on a employe a cette fin les informations publiees dans la litterature sur la fluidisation, qui portent sur de larges domaines des proprietes des fluides et des particules. Les resultats obtenus permettent de prevoir ces parametres aa partir de la seule connaissance du degre de vide du lit. Une comparaison entre cette correlation et celle de Chung et Wen(1) deniontre la superiorite de la premiere.

P. R. Krishnaswamy

Papers

Estimation of time delay time constant parameters in time, frequency, and laplace domains

Correlating parameters for axial dispersion in liquid fluidized systems