SU864525A2 - Adaptive threshold device - Google Patents

Description

(54) ADAPTIVE THRESHOLD DEVICE

i

The invention relates to a pulsed and computing technique and can be used in multifunctional logic circuits and as a central link in trainee classifiers, in particular in fault classifiers of various technical objects. .

According to the main auth. No. 661765, adaptive threshold devices are known that contain a weight adder, with an output connected: to the inputs of the comparison elements, the control inputs to the outputs of the element. adaptation, and inputs to the input buses, a valve whose output is connected through a divider to the first input of the adaptation element, the second input of which is connected to the output of the logic element, the control input of the valve is connected via a pulse generator to the installation input of the divider and directly to the first input of the logic element ,, the second input of the second comparison element connected to the output, a-, the third input - to the output of the first comparison element and to the input of the valve 1.

The disadvantage of such devices is that they can give a positive effect only in that case.

if training samples can be classified using the linear discriminant function ,. .

The purpose of the invention is the recognition of linearly unclassifiable images. To achieve this goal, an adaptive threshold device containing a weight adder is output connected to the inputs of the elements.

10 comparison, control inputs - to the outputs of the adaptation element, and inputs to the input buses, fan, the output of which is connected through a divider: to the first input of the adaptation element,

15 whose second input is connected to the output of the logic element, the control input of the valve is connected via a pulse generator to the installation input of the divider and directly to the first input of the logic element, the second input connected to the output of the second comparison element, and (the third input to the output of the first comparison element and a valve input, a switch, a functional converter unit, a control unit, a reversible counter, and an OR element, connected by both inputs to the control inputs of the weighing adder, are entered and the output to the input of the reversible counter, the output of which is connected to the input of the control unit, the first output of which is connected to the control input of the reversible counter, the second output to the control input of the switch, and the control input to the output of the functional converter unit input connected to the output of the switch, and the output to the informative input of the weight adder, the inputs of the switch connected to the buses of the input signals. Figure 1 shows the functional diagram of the device; figs, 2a, b are examples of linearly unclassifiable images in the two-dimensional space of features of figs; 2c is a pattern of transformation of linearly unclassifiable images into classified ones. The adaptive threshold device contains a switch 1 connected by an output to an input of a block 2 of functional converters, a control block 3, a reversible counter 4 and a logic element 5 ILM, a weight adder 6, the outputs of which are connected to the inputs of elements 7 and 7 of the comparison valve 9, a logical element 10, pulse generator 11, divider 12, adaptation element 13, tires 14 and 15 decreasing and increasing the weighted sum of inputs, polling bus 16, input buses 17 ... 17. The design of the newly introduced blocks and elements in many respects depends on the number of images and signs that go to the input tires 17. . .17u ,. If it is small, the switch can be performed on reed switches, and block 2 functional converters on nonlinear elements. In the case of a large number of features and training images, it is advisable to switch the switch on the basis of the MKS (multiple coordinate connectors, and as a functional transducer block, it is advisable to use functional transducers that are part of the analog or digital electronic devices. Block 2 serves for functional conversion Inputs are different, functions: power x, products O Xj, log of itw X, etc. The control unit 3 is designed to generate control commands d switch 1. Elok 3 should be performed on typical integrated circuits. Reversible counter 4 serves to set a certain number of training cycles to achieve which in block 3 you are given a pulse to stop the switch. The number of changes in weights comes from the input buses 14 and 15 of the weight adder 6 to logical element 5 OR, the need for a reversible counter 4 and element 5 is caused by the elimination of a looping when the discriminant function is incorrectly selected. The device works as follows. First, the limit number of learning cycles from control unit 3 is set for recording on the positive input to the reversible counter 4. Then, in accordance with the program issued by control unit 3, switch 1 connects the input values of attributes and supplies them to the input of block 2 of functional converters, in which the vector X is converted to a vector P. Each component of the vector F is, in general, an arbitrary function of the input vector X, i.e. -i (x) The values arrive at the input of the weight-adder 6, and the readiness of block 2 to form the next component confirms the benefit 1p to the second output of block 2 connected to the input of control block 3, according to the signal of which the switch selects a new sequence of initial features. In the future, with secondary symptoms leads to learning a well-known principle. In the case of the correct choice of the form of the discriminant function we obtain, the function YW-f - 5lW: f - W), which coincides - l-m, according to the sign indicating) the teacher. If the result is negative, the element 5 is read by the previously recorded number of changes in the weights from counter 4. At the moment of reading, a pulse is sent to the input of control unit 3 and the switch 1 is stopped. In this case, the learning process must be repeated, but for another kind of discriminant function. In Fig. 2a, two linearly unclassifiable classes are shown in the two-dimensional, feature space X, X2, and the training set is specified by the images), X (2, .CM). Through the introduction of -X, X. (y. And {KoNpoluchim (The table shows the preparation process at.

 ABOUT

1 о о 1 о о 1 о 0 в 70 - О 0 0 0

about 1 1 1

0O 1 -1

eleven

0-2

100

-one

eleven

- one

-about

2

about

0-1

ABOUT

-1 00 00 00

2 2 2

-eleven

one

-eleven

It follows from the table that (And Wjj -1 recognizes linearly unclassifiable images Xa,

Call of X

41

.2b in a two-dimensional feature space, two linearly unclassified 1x classes of images are shown:

, 1), x, 1/1, o; e w, i),

X2.2. (L,.

Figure 2b shows a linear (in the space {) discriminant function that separates these classes, this

-: П а5г 1 ЛЬ

Where

v-

.

 Wi-zl. N (/, -. 4.

After the device has been trained in recognition mode, the counter 4, the logical bridge 5, the element 7, the valve 9, the logic element 10, the generator 11, the divider 12, the element 13 and the buses 14-16 are not used.

The decision on whether the input image belongs to one of i rtaccoB is made by element 8 by comparing Z value with zero. With Z70 XGW.j, with g About X B.

Thus, the introduction of new blocks, zlemeny and communication in conjunction with the known allows to technically solve the problem of recognizing linearly unclassifiable images with accelerated adaptation and a reduced number of learning cycles in the event of a change in the sequence of images in the sample.

Claims (1)

Invention Formula Adaptive threshold device, auth.St. No. 661765, distinguishing itself, that, in order to recognize linearly unclassifiable images, a switch, a functional converter unit, a control unit, a reversible counter, and an OR element connected by inputs to the control inputs of the weight adder, and . as the input to the recursion counter, the output of which is connected to the input of the control unit, the first output of which is connected to the control input of the reversible counter, the second output to the control input of the switch, and the control input to the output of the functional converter unit, input connected to the output of the coupling number, and the output, to the informative input of the weighing accumulator, with the inputs of the switch connected to the buses of the input signals. Sources of information taken into account in the examination 1, USSR Author's Certificate No. 661765, cl. H 03 K 5/20, 08.12. (prototype).