PRINCIPLE OF PIEZOELECTRIC-TUNABLE TRANSDUCER

The effect of electric load on the characteristics of piezoelectric vibration systems was presentedin our recent papers.The resonance frequency of such systems can be changed continuously withthe electric load.In accordance with this effect,the piezoelectric-tunable transducers have been built. In this paper,the principle of the piezoelectric-tunable transducers is demonstrated while thepiezoelectric-tuning of the sandwich piezoelectric transducers are analysed theoretically and a sandwichtransducer of a longitudinal vibrating bar with field parallel to the length is investigated experimen-tally.The theoretical and experimental results show that such piezoelectric-tuning is effective inthree-halves octaves.This piezoelectric-tuning is convenient for the piezoelectric-tunable transducers,and can be carried out continuously and instantaneously.     

DESIGN PRINCIPLE OF A LONG-RANGE BROADCASTING

A long-range broadcasting system may be considered as a system of speech transmission.Theprincipal parameters involved in this system are the average spectrum of speech,the function ofsignal pre-emphasis,the characteristics of electro-acoustic transformation and the attenuation forsound transmission in air.At present,the relations between these parameters and frequency usuallyare described by diagrams or quasi-empirical formulas.In most cases,the interrelations among theseparameters are complicated,and designing the broadcasting system are difficult.In this paper,onthe basis of theoretical derivations and experimental results of these parameters,the approximateanalytic formulas of the relation between these parameters and frequency are obtained by using themethod of curve fitting.It is convenient to design a broadcasting system by using these formulas.As an example,a design method of a broadcasting system for 8—10 km is introduced.     

INFORMATION PRINCIPLE OF ACTIVE SONAR DETECTION

The relations between three factors:waveform,channel and receive of active sonar is discussedin this paper.The models of active sonar channel,which includes marine reverberation,signalpropagation and object scattering are described by the widesense scattering function and the wide-sense coherence function.Physical meaning of both functions are explained with the aid of channeloutput correlation function and matched filter output respectively,the fundamental principle for thedesign of the optimum waveform and the optimum receiver are presented.     

CAN THE PRINCIPLE OF MICROCAUSALITY BE REMOVED ARBITRARILY?

We discuss the problem of microcausality in a model of quantized field theory. Under the assumptions that the commutator of the "in" fields satisfies the requirement of translational invariance, we show that, in the case of self-conjugate scalar particles or particles with integer spins, one can deduce the law of microcausality.     

PRINCIPLE OF PIEZOELECTRIC DAMPING OF VIBRATION:AN EXPERIMENTAL INVESTIGATION

Since the vibration behaviours of a piezoelectric vibration system change with an electrical load,thevibration of such a system will be damped,when the electrical load includes a resistance component.Basedon this effect,a principle of piezoelectric damping of vibration is developed.In this paper piezoelectric damping configurations for both thickness and longitudinal vibrations areexperimentally studied.The results show that the piezoelectric material may become a new type of materialfor damping and the piezoelectric vibrator can be used as a new type of damper.The piezoelectric damping adjustment is convenient and can be carried out continuously andinstantaneously.     

SO(10)×SU(4) CHIRAL PREON MODEL SATISFYING COMPLEMENTARITY PRINCIPLE

We extended the MAC principle to the case for semisimple metacolor gauge group and the constructed and SO(10)×SU(4) chrial preon model which satisfies the complementarity principle.This model had a unique solution and thus predicted 4 generations of quarks and leptons without exotics.The generation gauge group was intruduced and the breaking of mass degeneracy among different generations was investigated.     

A POSSIBLE GENERALIZATION OF THE SCHRÖDINGER EQUATION BASED ON THE GAUSS PRINCIPLE OF LEAST SQUARES

The linear Schrödinger equation is generalized into non-linear equation based on the Gauss' principle of least squares. The weight function is assigned in such a way that it might be interpreted as occupation number density of hidden particles that obey the Fermi–Dirac stastistics. It is shown that the motion of a free particle, according to the so generalized non-linear equation, is described by a well behaved nondeforming wave packet moving with a constant velocity, in contrast to the always deforming wave packet according to the linear Schrödinger equation.