This paper describes some phenomena in which an apparent reverse relationship between cause andeffect occurs in a cement rotary kiln process. Among them, two items are picked up. One is apparentreverse response caused by poor information transmitted from the radiation pyrometer with regard to theburning zone temperature.
The other is the reverse relation effected by two variable control by means of one common actuation.
In this paper, author treats how the digital compensations and probable decisions must be taken under such circumstances.

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In general, indicial response of well-designed feedback control system is a little oscillatory and hasan overshoot. In some cases, however, the overshoot will be severely limited or will not be permitted atall. As examples of these cases, there are automatic position control of jig borer, automatic feed controlof electro-errosion machine and balancing type recorder. Given in this paper is a synthesis method forsuch systems. Indicial response of 2nd order system which has double negative real roots and has no zerois called critical damping response and has no overshoot. It is also well known that indicial response ofhigher order system which has dominant double negative real roots can be approximated by the indicialresponse of 2nd order system which has same double roots as those of higher order system. In thispaper, such a system is called critical damping system and considered suitable for systems mentionedabove as examples. Principle of “dominant root specifying method” was developed into the synthesis ofcritical damping system, and formulas and charts were obtained convenient for the synthesis. Using thesedata, a designer can select a type of compensating network available for the given specifications anduncompensated system, and easily calculate without any experience values of parameters of transfer functionof the selected compensating network. In this paper, three examples, that is, for 1-type system, 0-typesystem and process control system with dead time, are given together with good coincidences between the given specifications and the results of synthesis.

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As a constriction to obtain small flow rate, straight orifices (small size MOD. ASME) and capillariesin combination with an integral orifice d/p cell are discussed to yield the following conclusions.
In the straight orifice:
1) When orifice diameter is nearly equal to its thickness, flow coefficient is most hardly influencedby Reynolds number in the ranges of orifice diameter of 0.3 to 4mm and Reynolds number of 5 to50, 000.
2) Once flow coefficient is empirically decided at a point in an adequate flow range, a measuring, accuracy of ±2% is expected.
3) Compared with quardrant-edge orifice, it is easier in manufacture and more practical in use.
4) In fluid viscosity range 1cP to 10cP, it was ascertained that its characteristics remains unchangedso long as Reynolds number is kept constant.In the capillary:
1) In case the fluid is water, Hagen-Poiseuille's equation is congruent with actual measurement solong as the flow state remains laminar.
2) In case the fluid is water, a critical Reynolds number, beyond which Hagen-Poiseuille's equationcan not be formed, is in proportional relations with the ratio of the diameter to the length.
3) When the diameter comes less than 0.mm, dust is apt to disturb flow and thus good repro-Aucibility is not expected.
4) When fluid viscosity comes over 5 cp., Hagen-Poiseuille's equation can not be formed even if the flow state remains laminar.

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In recent years, control technology has entered an entirely new stage. Designer is attempting tocontrol exceedingly complex processes such as multidimensional processes. General theory of invarianceformulated by Kulebakin and his associates of the U. S. S. R. Academy of Science offers new effective waysdesigning such complex systems. Given in this paper is a brief introduction of Kulebakin's invarianceprinciple and its application to the design of compensating element of tension control systems.

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