This paper pointed out that the Wyle-symbol method for run length coding of binary image does not make use of the ability of the coding-word fully,and presented an improved method,which can increases the compress ration apparently.

Furthermore,the condition was applied to symbolic algorithm of global optimization of the class of radical functions.

In the alternating current teaching, and the symbol method is one kind of analysis method of important exchange circuit in common use, and that the sine with the symbol method begged with the frequency is measured and differs from superiorly in separates dividing type and waveform picture, and possesses the merits such as the picture is distinct and the concept accurate and counts reasonable etc.

The coordinate transform and symbol method were used to derive the six-freedom robot s kinematics equation.

The relations between the terminal voltage of the bulb and phase－sequencc in phase－sequence de－tection electric circuit are studied in theory and quantitative analysis by using Kirchoff s laws and sine－type al－ternating current symbolic method.

The formal methods of security protocol was categorized as two classes: the symbol approach,and the computatio￣nal approach.

The symbol approach and the computational approach are two different approaches in security protocols formal analysis, but the former is quite alien to the latter.