Sets of vectors of decimation indices IS = (d1, d2, …, dn) for the formation of sets of septenary sequences with a low level of mutual correlation in finite fields GF(7S) are presented. Based on the decimation of the symbols of the basic M-sequence, sets of septenary gold-like sequences with a period N = 7S–1 (S = 2, 3, 4, 5) are obtained. The values of the periodic cross-correlation function, the power of the generated sets and the number of sets with equivalent properties are given.

It is proposed to use the properties of weight-transition sum code for organizing built-in control circuits of combinational digital devices when checking calculations by two diagnostic features. It is established that the control symbols of weight-transition sum code are described by the so-called self-quasi-dual Boolean functions that have the same values on pairs of input combinations that differ in all variables. This property can be used in the synthesis of built-in control circuits based on Boolean signal correction. A built-in control circuit based on Boolean signal correction with verification of the belonging of the generated code words to the weight-transition sum code, as well as self-quasi-duality of each calculated function, is presented. An algorithm for obtaining the values of Boolean signal correction functions is given, which guarantees the self-quasi-duality of the functions formed in the built-in control circuit, describing the data and check symbols of the weight-transition sum code, as well as self-checkability of the built-in control circuit itself.

Components of instrumental error of a precision tilt meter, in which pendulum compensation accelerometers are used as sensing elements, are considered. The use of a rotary platform in the design of the tilt meter makes it possible to minimize the effect of temperature on the result of measuring the angle of inclination of the surface, and thus compensate for the change in the zero offset of the accelerometer over time. The errors in measuring the angle of inclination of the foundation on which the test equipment is installed caused by errors in accelerometers and the tilt platform of the tilt meter have been evaluated, and the causes of their occurrence have been investigated. Solutions are proposed to minimize the impact of these errors.

The influence of surface characteristics of the working blade of steam turbine low-pressure cylinder and parameters of optoelectronic system elements on the chord length control error during turbine rotor barring is investigated. Experimental studies show that the spectral coefficient of diffuse reflection of the working blade surface in different sections of the surface of a worn and new blade can vary from 0.03 to 0.18, and thus confirm the need to take these changes into account in the system design. The algorithm for determining the chord length is improved, the algorithm includes the operation of morphological closure with a structural element in the form of a circle with a diameter equal to a quarter of the width of the working blade image, and allows for removal of pulse noise from the video camera. Studies on a computer model using the improved algorithm demonstrate that the signal-to-noise ratio at the input of the video probe receiver should not exceed 15 dB. Experimental studies of the system model in statics with a worn working blade with a chord length of 102.4 mm reveal that the standard deviation of the length estimates does not exceed 0.19 mm, which confirms the effectiveness of using the proposed version of the algorithm.

An optoelectronic device is considered, which implements a three-axis gyrostabilization system that ensuring effective operation in pitching conditions. A finite element model of the optoelectronic device functioning under the action of harmonic vibration and mechanical shocks associated with its operating conditions is calculated. The effect of dynamic influences on the position of the axes of sight of the optical devices included in the device is investigated. The deviations of the sighting axes obtained as a result of the calculation under the action of harmonic vibration exceed the permissible values. In order to reduce the influence of dynamic effects on the accuracy characteristics of the optoelectronic device, recommendations are given for refining the design to improve vibration tolerance.

A photographic optical system with a lens designed for an object located at infinity and an image located in the rear focal plane is investigated. Matching criteria for the optical system (lens) and the receiving surface (CCD or CMOS receiver) related to the assembly, adjustment, and material base of the system are formulated. Examples of matching optics with a flat and non-flat receiving surface using the proposed method are given. Taking into account the selected matching criteria during assembly and adjustment of the lens and receiver allows for installing the receiver in the plane of the best image quality. Using a receiver with a curved photosensitive surface changes the order of calculating the matching criteria. The proposed method for matching lens and receiver can be useful in designing optical systems, developing receiving devices, and also in assembling and installing the lens for correctly assessing the permissible values of linear and angular deviations.

An approach to training diagnostic models of complex technical systems with multiple uncertainty of a priori information is proposed. Since it is impossible to determine the law of distribution of values of parameters of working processes, it is proposed to use methods of nonparametric statistics. The training procedure is based on the use of topology and properties of finite-dimensional Euclidean spaces. An example of a training procedure using a computational scheme according to the Robbins-Monroe algorithm is given. A graphical interpretation of the construction of a standard of parametric failure of an element when constructing diagnostic models of equipment of the ventilation and air conditioning system of a clean room of a special facility is presented.

A method for assessing the reliable provision of a given accuracy by current technological processes and an algorithm formed on its basis for evaluating the accuracy assessment for the technological processes are proposed. Testing on factory technological processes confirmed the adequacy of the proposed methodology and the operability of the created algorithm, and also made it possible to identify shortcomings and errors made by the technologist, in particular, during the development of manufacturing technology for prismatic parts, for which appropriate recommendations are formulated.

The possibility of periodic participation of a human operator in the control system of the component assembly robotic module is considered. It is noted that the probability of occurrence of erroneous commands from the operator is determined by the level of his performance. A mathematical model is given for assessing the performance of a human operator during a work shift.