Emphases are placed on open loop S/H amplifiers, high accuracy S/H amplifiers with closed loop structure ( bipolar ), total difference high-speed track/hold amplifiers (BiCMOS) and very high-speed S/H amplifiers (GaAs).

This method can improve the accuracy of deflection control and stability of tracking measurement. To improve the position control accuracy of copying system, the closed loop structure of position control based on PID controller is designed; the PID parameters are optimized through genetic algorithm;

The control scheme consist of two layer position feedback covering nonlinear hawser drive system can supply a gap of half closed loop structure with only encoder feedback so can improve stability and robustness of control system.

Due to its closed loop structure, the capabilities of 2D pneumatic digital valve, such as its stability, rapidness, precision and rigidity restrict each other. Effects on the above mentioned performance indexes caused by changes of the structure parameters are neither linear nor identically progressive or degressive.

This paper introduces a kind of economical lathe CNC system which is controlled by a 8098 sngle chip controller based on a half closed loop structure, gives out the controlling tactics of overcoming the pulse losing, main module of system software for lathe reforming.

Predictive control algorithm is a new type of computer control algorithm developed since the middle of 70's. It is characterized by its easily modelling, simple on-line computation and comprehensively good control, quality.Based on the step response of a linear plant, this paper proposes a new method of designing digital controllers in predictive space. The theoretical background of the predictive control algorithm is explained. The closed-loop structure, the setting procedure for design parameters...

Predictive control algorithm is a new type of computer control algorithm developed since the middle of 70's. It is characterized by its easily modelling, simple on-line computation and comprehensively good control, quality.Based on the step response of a linear plant, this paper proposes a new method of designing digital controllers in predictive space. The theoretical background of the predictive control algorithm is explained. The closed-loop structure, the setting procedure for design parameters and the implementation of the new algorithm are discussed. Finally, the performance of the new method is demonstrated by some examples with computer simulation and experiment.

A research in DNA difference of variousstrains of lepospires by means of the restric-tion endonucleaes analysis and EMSMDAPFis reported for the first time in this paper.The DNA of 5 strains of leptospires, strain017 of serovar. Lai of serogroup L.interro-gans, strain patoc Ⅰ of L. biflexa, etc.,were digested by EcoR Ⅰ, Hind Ⅲ,Bgl Ⅱ, Hha Ⅰ and BamH Ⅰ restriction en-donuclease, and a horizontal electrophoresisof agarose was carried out. After that, thefragments of DNA in which the differencewas found were retrieved...

A research in DNA difference of variousstrains of lepospires by means of the restric-tion endonucleaes analysis and EMSMDAPFis reported for the first time in this paper.The DNA of 5 strains of leptospires, strain017 of serovar. Lai of serogroup L.interro-gans, strain patoc Ⅰ of L. biflexa, etc.,were digested by EcoR Ⅰ, Hind Ⅲ,Bgl Ⅱ, Hha Ⅰ and BamH Ⅰ restriction en-donuclease, and a horizontal electrophoresisof agarose was carried out. After that, thefragments of DNA in which the differencewas found were retrieved and EMSMDAPFwas conducted. A remarkable difference was found inDNA of various groups, sero-types of lepto- spires in the restriction endonuclease patternand a gentle difference of one or twobands, however, was observed in strain 017and 601 only. On the EM, multipledegreebranching structure of DNA in L.biflexaPatoc Ⅰ and Leptonema illini strain 3055,single-degree branching structure in L.heb-domadis strain 245 and straight stem orsuper-helical structure in strains 017 and 601of L.interrogans were found.In the differ-ence between strains 017 and 601 the closed-loop structure was observed in the former. It is suggested that the difference in themolecular composition and structure of DNAin various strains of leptospires is beneficialto the taxonomy and identification in lepto-spires, and is likely to be related with thevirulence of leptospires to a certain extent.

In this paper, a general purpose computer program SNERM based on the Subsystem Newton-Euler Recursive Method for both the kinematics and dynamics of multibody systems, is introduced. The SNERM program is constructed by a main module for dealing with the dynamics of the manipulator chain structure and a series of subprogram modules for dealing with the dynamics of complicated systems with joints of multidegrees of freedom, with kinematic excitations, with reference body motions and with complicated topological...

In this paper, a general purpose computer program SNERM based on the Subsystem Newton-Euler Recursive Method for both the kinematics and dynamics of multibody systems, is introduced. The SNERM program is constructed by a main module for dealing with the dynamics of the manipulator chain structure and a series of subprogram modules for dealing with the dynamics of complicated systems with joints of multidegrees of freedom, with kinematic excitations, with reference body motions and with complicated topological structure.A Singular Value Decomposition (SVD) subprogram module is enclosed, so the SVD reductive method for the dynamics of constrained multibody systems can be applied and the Kinematics of the system with redundancy can be solved. The SNERM program, which is efficient and suitable for engineerirg applications, has a series of recursive and formulized formatting computations. It can be expansively applied in the kinematics and dynamics of general multibody systems, such as the spacecraft, the robots, the vehicles and the mechanisms etc. The characteristics of the Subsystem Newton-Euler Recursive Method is introduced briefly and a series of recursive and formulized formatting equations are presented. Two numerical examples are introduced. One is for the dynamics of the mechanism for a reference body with rotation, and the other is for the dynamics of a system with closed loop structure. It is shown that the SNERM program has good expansibility and accuracy and may be widely used.