Based on water conservation theorems and principle that sum of head losses in any closed loop e-quals zero,model for two-dimensional fissure network seepage is established. Problem of fissure network seepage is established,’Problem of fissure network seepoge with free face is solved by primary flow method for seepage with continous midium and free face.

The magnetic field of dry-type air core reactor with spatial closed loop is calculated with analytic method. And the effect of closed loop on parameters of a reactor is explored.

It is proven that a number min{ max { 2m + (p - l)[2m/p], 2p + (m-1) [2p/m] } ,n}of the closed loop system poles are arbitrarily assignable (n is order of the system, p = rank B, m = rank C), Finally, the method is illustrated by the numerical example.

Moreover,a list of optimum parameters σ_(max),T/T_(3(),K_(N+1) T_3()~N had been included to make the optimal design of the closed loop control system easier.

To meet the requirements of the double wire pulse MAG welding process, a novel double wire pulse MAG welding inverter integrated with technologies, such as soft-switching, double closed loop control, and synchronic control, is produced.

Improvement of the cascading closed loop cycle system

Aspen Plus was used to simulate and get more information about the cascading closed loop cycle (CCLC) system [1-3].

A method is presented for synthesis of optimal sampled-data tracking systems with two controllers, one of which is incorporated into the closed loop, while another is placed in feedforward chain.

The problem of linear control by the desired matrix transfer functions of the closed loop under incomplete information about the object state vector was considered.

The main point of the method proposed in this paper is that the form of the transfer function of the equivalent feedback compensation is specified at the outset. The form of the transfer function is specified with due consideration to stability, transient performance and possibility of realization. According to either the required open-loop or closed-loop transfer function the parameters of the compensating networks can he calculated easily.

In this paper, mainly discuss the synthesis method of combined control systems (systems both contain open loop and closed loop control circuits). Suggest a simple method to calculate the system integral-square error by its logarithemic frequency characteristics. This method can easily be applied to synthesize the feedforward networks. When the output of the actuating element is subjected to some integral limit conditions, or the discrete circuit is used as feedforward unit, the synthesis method of feedforward...

In this paper, mainly discuss the synthesis method of combined control systems (systems both contain open loop and closed loop control circuits). Suggest a simple method to calculate the system integral-square error by its logarithemic frequency characteristics. This method can easily be applied to synthesize the feedforward networks. When the output of the actuating element is subjected to some integral limit conditions, or the discrete circuit is used as feedforward unit, the synthesis method of feedforward network is also discussed.

In this paper it is demonstrated that the south-pointing-chariot invented about twothousand years ago is an open-loop regulating system based on the disturbance compensa-tion principle. And about nine hundred years ago in North-Song Dynasty, Su Sung andHan Kung-lien built a water-powered astronomical apparatus, in which a balancing de-vice, an automatic controller activated by the error of the regulated variables, was used.The block diagrams and transfer functions of these two systems are given in this...

In this paper it is demonstrated that the south-pointing-chariot invented about twothousand years ago is an open-loop regulating system based on the disturbance compensa-tion principle. And about nine hundred years ago in North-Song Dynasty, Su Sung andHan Kung-lien built a water-powered astronomical apparatus, in which a balancing de-vice, an automatic controller activated by the error of the regulated variables, was used.The block diagrams and transfer functions of these two systems are given in this paper. Two parameter stabilizing systems, namely, the water clock and the constant speeddriving system in the water-powered astronomical apparatus are also introduced. Inboth cases, the influence of the external disturbances upon the stabilized variables areautomatically compensated. The author analysed the various automatic equipments in Ancient China andgrouped them into six classes: automatic transducing and signalling system, open-loopcontrol system, open and closed-loop regulating system, open-loop programming system,parameter stabilizing system and simulation of the systems. It is concluded that achieve-ments in automatics in Ancient China was quite significant compared with the situationthen existing in other countries.