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The task of determining the end point (DEP) of the transient process (TP) in the measuring circuit (MC) during testing of complex objects (CO) is currently relevant. The real MC has a priori parametric uncertainty (PU). It is PU that determines the significant dynamic error (DE) of the first kind when determining the end of the dynamic test mode. For example, estimates of the relative error of DEP TP are known to arise due to the improper application of the interval type criterion (ITC) for CO with a first-order dynamic model. The importance of solving this problem is emphasized by its inclusion in Russian and foreign standards on methods of conducting CO tests in various technologies. Previously, we found the presence of a critical constant criterion (CCC), which is determined by the nominal value of the system parameter (SP) PU. Such a modified interval criterion should ensure acceptable DEP quality. Robust properties are provided due to a specially developed algorithm for the functioning of the ITC. Based on the analysis of the dynamics of the increments of the deterministic TP signal, a criterion for evaluating the quality of automatic monitoring of the duration of the observation interval (DOI) control is developed. Moreover, the evaluation criterion has a quadratic character, which made it possible to apply extreme control methods. A block diagram of the DOI control based on the processing of the TP measurement signal is developed. A digital simulation of the modified interval criterion is performed. The simulation showed the effectiveness of the proposed solution of the DEP TP problem in the possible range of variations of the MC mathematical model. Moreover, the solution is guaranteed to provide DE at the acceptable level.

When testing complex objects, it is recommended to use standardized criteria to determine the moment of the end of the transient process (TP) in the measuring circuit (MC). The criteria of the interval type (CIV) analyze the current increment of the TP signal in the MC. The paper considers only TP with first-order dynamics. It is known that the CIV has a significant restriction on its application: when the parameter of the TP model exceeds the critical constant of the criterion (CPC), we get a significant excess of the dynamic error (DE) achieved at the observation interval (OI) over the permissible level (PL) and, consequently, a false positive decision of the CIV about the beginning of the static measurement mode.The paper presents an algorithm of the robust interval criterion (RIC) – as a modification of the CIV-for determining the end point of the TP. Robustness is achieved by using a tunable implicit reference model. The controlled parameter of the RIC is the duration of the OI for the TP signal. Based on this duration, the current value of the PDA and the parameter of the reference model are calculated. The difference between the signals about the expected duration of the TP from the reference model and the moment of decision-making is information for setting the parameters of the RIC. Thus, the optimal value of OI is found.The research was carried out by the method of simulation modeling using the Monte Carlo method. The results of the research are the evaluation of the effectiveness of the robust interval criterion in the case of its application over the entire possible interval of a priori parametric uncertainty in comparison with the results of the functioning of standardized CIV. The obtained statistical results confirm the high reliability of the RIC operation and the absence of false-positive solutions in the analysis of transient signals for first-order dynamical systems.

The paper is devoted to synthesizing the structure of a noise-invariant analog-to-digital converter of pulses having random lengths and moments of appearing and distorted by low- frequency interference and white noise with a normal distribution law. The main idea is based on using a simple Markov chain with two states to describe a sequence of changes in the states of pulse with respect to any of the allowed levels of quantization.

The work is a development of the interval criterion for determining the moment when the steady-state value of the transition signal occurs. These criteria are used in technologies related to testing complex objects under conditions of parametric uncertainty of its model. The transient signal is analyzed in on-line mode. Therefore, the accuracy of the decision about the time of the end of the tests determines the cost of conducting them. Such tests are characterized by significant dynamic errors that significantly exceed the allowed level. The reasons for this are the parametric uncertainty in the mathematical model of the object and the inability of the deterministic interval criterion to correctly issue a solution under these conditions. It was previously determined that the interval criterion is characterized by the presence of an asymptotic critical value of the criterion. Exceeding the object’s real time constant over the critical value gives a false positive result. This situation is characterized by the fact that the desired moment is falsely determined significantly earlier than the optimal solution. You can avoid this situation if you set the criteria to the maximum constant of the object’s time. However, this choice leads to significant time losses when analyzing the transition signal. The solution of the problem of guaranteed provision of a given level of dynamic error over the entire range of values of the object model parameter is possible using a robust algorithm. The basis for constructing a robust criterion is to control the duration of the observation interval. For this purpose, the current information about the analyzed signal is used. There are three ways to apply the current information. The first approach is based on the use of an extrapolated estimate of the established value. This allows you to determine the estimate of the current dynamic error and prevent a falsely positive decision of the criterion. The second approach is based on the analysis of the dynamics of the current increment of the transition signal at neighboring observation intervals. The third is based on the use of a reference model of the transition process in the measuring channel with a parameter equal to the critical value of the criterion. Based on the analysis of current information, the critical value of the criterion is redefined. With the new value, monitoring of the transition process continues until a positive decision is made about the moment when the steady value of the transition signal occurs.

The paper is devoted to determining the duration of on-line expensive and unique tests in the presence of parametric uncertainty of the test object model. It is demonstrated that the error in determining this time leads either to an identification error of the object, or to significant resource costs. The relevance of the task is confirmed by cited plural references. An asymptotic critical value is found for the interval criterion what establishes some restrictions in determining the test duration. It is shown that under any accuracy of the critical value, the use of the interval criterion outside the specified parameter range leads to significant dynamic errors during testing which are unacceptable. The paper novelty lies in determining the border between the normal functioning of the interval criterion for online measurement of the transition process duration during testing and the case when this criterion gives a false-positive result. Therefore, the consumer of measurement information cannot be misled; hence, risks of unjustified losses are minimal. The found asymptotic value of the interval criterion can serve as the informational basis for the different criteria, e.g., robust criteria.

This paper describes the method of practical tuning parameters of a built-in infrared (IR) sensor with matrices of photosensitive elements aimed to register light pulses in order to control different automatic systems. The method searches the optimal values of the low and high frequencies of the bandpass filter and the sampling period of the switcher using the genetic algorithm of optimization. The optimality criterion is based on comparison of the bandpass filter with the optimal filter. The experimental results have shown possibility to significantly improve signal-to-noise ratio during pulse detection and its amplitude measurement.

This paper describes the new method of pulse sequence stabilization which can be applied to different tasks of automatics and energetics. The originality of the method comes to using state estimators of pulses on the base of the probabilistic relay. The pulse sequence is observed on the complex background including multiplicative and low frequency interferences and additive white noise. The results of simulation modeling with rectangular and bell’s shaped pulses have shown that the suggested method provides sure restoration both magnitude and form of pulses with reasonable relative errors for different noise and interference combinations.

The time limit of the transient process (TP) in the measuring circuit (MC) is determined by known criteria. These criteria use a first-order dynamic link model. Typically, this model is a priori model for the measurement problems discussed above. In on-line mode, the interval criterion (IC) is used. There is a limitation in the form of a critical value of the time constant (TC) to apply the criterion. Previously, it was found that such a restriction exists for the MC model in the form of a dynamic link of the second order. The functional dependence of the critical value on the parameter in the form of the ratio of the second-order dynamic link TC model was found. This restriction on the use of IC develops the fact that there is such a restriction for MC with a first-order model. It is advisable to analyze the performance of the IC for the third-order MC model. These models are widely used in the simulation of measuring channels. Thus, it is possible to generalize such studies. In this study we used a model with transfer function presented in terms of the diagram Vyshnegradsky with parameters "A" and "B". In this paper, the IC is analyzed for the area of the aperiodic regime of the MC. The simulation results showed that the functional dependence of the critical value on the parameters is presented as a complex surface. For the bisector of the diagram at A and B>8, the critical value is stabilized and set at the level characteristic of the first order model. Based on the information about the behavior of the critical value of the interval criterion for MC with structural uncertainty, it is possible to construct robust algorithms that implement IC. The time limit of the transient process (TP) in the measuring circuit (MC) is determined by known criteria. These criteria use a first-order dynamic coupling model. Typically, this model is apriori model for the measurement problems discussed above.

We suggest a relatively simple method of simulation modeling channel noises for different infrared (IR) sensors to avoid their physical or mathematical modeling. Now, instead of solving complex equations, there are used three random number generators to simulate fixed pattern noise (FPN) of sensitivity, dark current and additive correlated noise for each channel of the IR-sensors with different variants of photosensitive elements placement. The method can be useful for developing different algorithms of IR image processing.

The paper describes the new methods of applying the standardized interval criterion for the transition process end during testing complex objects. Analysis of signals in the measuring system is carried out in on-line mode. The classification of the transition process end criteria and correlation of the interval criterion with the known ones are considered. The examples of such criteria in measuring instruments are given. The criterion of the interval kind uses the current information about the permissible increment of the transient signal in the measuring circuit in a given observation interval. The analysis of the interval criterion has shown that there are some restrictions on its application due to a significant dynamic error during measuring the time of the transition process end. It is explained by the parametric and structural uncertainty of the measuring circuit. The parameters of the criterion determine the critical value of the time constant of the measuring circuit model and the area of its use. The results of the digital simulation of applying the interval criterion for the transition process end when measuring the temperature of the test object with dynamic sensors of the first and second orders are presented.

As is known, the reactive power of the signal can be determined by the phase shift of one of the signals to ${\pi}/2$ radians and the subsequent application of the active power measurement algorithm. The time delay units, integrators and differentiators are used in practice to perform phase shift. However, the application of these devices is limited by the requirement of sinusoidal input signals. This paper consider the method of phase shift of one of the signals to ${\pi}/2$ radian by using a digital Hilbert transformer. The application of this method allows to measure reactive power for polyharmonic input signals at the required frequency band. The effect of the order of the Hilbert transformer on the measurement error of reactive power is considered. A comparison of the digital implementation of the Hilbert transformer using the IIR-type digital filters and IIR-type digital filters is performed. The obtained analytical expression allows to estimate the error of measurement of reactive power due to the frequency deviation and phase response of the Hilbert transformer from the nominal value. Popular method of measuring of the active power based on the averaging of instantaneous power is considered. The analytical expressions relating the input signal frequency deviation and the measurement error of reactive power for the considered measurement methods are obtained. The validity of the obtained expressions is confirmed by simulation results of the mathematical modeling performed by the Simulink package software.

To measure the active power in a given frequency band, a method based on low-pass filtration of the instantaneous power signal can be applied. For active power digital meters, the low-pass filter is implemented digitally. At the same time, infinite impulse response (IIR) digital filters, finite impulse response (FIR) digital filters can be used to perform low-frequency filtering. The article shows that the parameters of the applied digital filter are significantly affected to the measurement error. The application of cascaded integrator-comb (CIC) filters plays an important role. The article shows that when using a complex circuit containing a CIC-filter and a IIR-filter, the smallest measurement error (among the considered digital filters) is shown. Analytical expressions are obtained, which allows to contact the measurement error of active power and the parameters of the applied digital filter. To verify the reliability of the obtained analytical expressions, simulations were performed in the Simulink software package.

This paper describes the new method for analysis of different criteria intended to calculate the end of the transient process in the measuring circuit. The method uses an admissible absolute or relative form of the dynamic error of measuring the moment of steady-state transient response value by the criteria which are referred as the interval type criteria. The circuit model is represented by a dynamic element of the first order. The paper contains the results of the interval criteria analysis in various forms.

This paper describes the new method for quick estimating impulse parameters from light point sources for their detection and coordinates estimation in onboard infrared (IR) sensors. It is considered the case when the IR-sensor has the line of photoelements with interlaced photosensitive squares; moreover, the diameter of the light spot from the point source and the size of the photoelement are equal to each other. The method uses the matching filter based on the statistically linearized model of impulses appearing in corresponding electronic channels. The model allows calculating the estimators of impulse magnitude and position directly taking into consideration small quantity of samples for channel impulses, voltage shifts and correlated white noise for each photoelement. The numerical analysis has shown that the suggested method provides good accuracy for weak channel impulses that allows successfully detecting the point source and estimating its rough coordinates.

This paper describes the method for quick calculating rough estimators of channel impulses from point sources for their detection and coordinates estimation in onboard infrared (IR) sensors. It is supposed that the IR-sensor has the line of photo elements with interlaced photosensitive squares and the diameter of the light spot from the point source is equal to the size of the photo element. The method uses the matching filter based on the model which describes the cases of small quantity of samples for channel impulses, voltage shifts and correlated white noise for each photo element. The experiments have shown that the suggested method provides restoration of weak channel impulses that allows successfully detecting the point source and estimating its rough coordinates.

This paper describes the criterion of the end of the transient in the measuring circuit. The circuit model is represented by a dynamic element of the first order. The standardized interval criterion that is characterized as an empirical one is shown to be widely used in the digital measuring devices such as power transformer winding resistance meters. The dependence of the critical value of the maximum time constant of the measuring circuit is found.

This paper presents the results of new research on neural network classifiers for barriers on traffic routes of locomotives. The general structure of the system of detection, recognition of traffic barriers, input information coming from the subsystem of the computer vision and the subsystem that scans spaces in front of the locomotive are considered. The methods of image fusion based on an adaptive processing of wavelet coefficients are used to increase the resolution of images. A multilayer neural network with error back propagation is used as a classifier.

This paper presents the results of new researches of the method of sensors dynamic characteristics correction — a method of transient response signal forcing in the measuring circuit of the sensor. The efficiency of the forcing method is shown in comparison with the classical algorithm that expects the end of the transient response in the measuring circuit. The limits of the range of the method's main parameter — a signal forcing coefficient are considered. The method is applicable for DC measurements of winding resistance of power transformers or measurements of a constant temperature of the object under step exposure to the sensor. This paper summarizes the development trends of this method of correction that is based on the iterative approach to the conversion of physical quantities. Three-point algorithm of the method of selected points is used as base algorithm for information processing. Maximum error of assessment of the asymptote of a transient response in a measuring circuit described by a first-order circuit is analyzed.