Jozef Wiora

Silesian University of Technology · Department of Measurements and Control Systems

Particulate matter (PM) suspended in the air significantly impacts human health. Those of anthropogenic origin are particularly hazardous. Poland is one of the countries where the air quality during the heating season is the worst in Europe. Air quality in small towns and villages far from state monitoring stations is often much worse than in large...

We know that least Lp-norm filters, processing a one-dimensional signal within a time window, are suitable for attenuation of impulses. This article proposes a new analogue filter with exponentially weighted old samples, which is a generalization of the first-order low-pass filter. The obtained formula describing the output signal is presented in a...

The growing popularity of ESP boards has led to the development of several programming platforms. They allow users to develop applications for ESP modules in different programming languages, such as C++, C, Lua, MicroPython, or using AT Commands. Each of them is very specific and has different advantages. The programming style, efficiency, speed of...

The growing popularity of ESP boards has led to the development of several programming platforms. They allow users to develop applications for ESP modules in different programming languages, such as C++, C, Lua, MicroPython, or using AT Commands. Each of them is very specific and has different advantages. The programming style, efficiency, speed of...

Fractional-order (FO) differential equations are more and more frequently applied to describe real-world applications or models of phenomena. Despite such models exhibiting high flexibility and good fits to experimental data, they introduce their inherent inaccuracy related to the order of approximation. This article shows that the chosen model inf...

The purpose of an automatic control is to provide the best quality of the output signal of a controlled object. This quality is dependent on the type and tuning parameters of the used controller and on the properties of a transducer measuring the output signal. In this work, it was considered how the imperfections of the transducer propagate by the...

Glass pH electrodes are still successfully applied in the chemical and environmental industry. During their long-term use, periodic calibration is required to maintain the required accuracy of measurements because the parameters of the electrodes change over time. This work presents an aging of 11 pH electrodes within approximately 600 days in tap...

An assessment of measurement uncertainty is a task, which has to be the final step of every chemical assay. Apart from a commonly applied typical assessment method, Monte Carlo (MC) simulations may be used. The simulations are frequently performed by a computer program, which has to be written, and therefore some programming skills are required. It...

This paper describes a way of determining selected water parameters using a prototype of a remote-controlled catamaran. The remote controlling allows to steer the boat and to manage the measurement process from the shore. It is possible to monitor the water parameters online as well as to store them and analyze them afterwards. The measured paramet...

Acoustic insulation of a device from the environment can be enhanced by appropriate control of its casing vibrations. The level of noise reduction obtained in such way is considered as the main point for evaluating the performance of the active control system, hence its appropriate measurement constitutes a vital issue. In this study, measurement u...

According to recent findings, it is possible to computationally determine a measurement result (value and uncertainty), using a special measurement method, in which this uncertainty is less than that assessed directly from experiments using Type B evaluation. The method works well only if the quantity is additive and its uncertainty is constant, i....

Parameters of a model describing a measurement process obtained during a calibration experiment allow one to calculate a measurement result, but a simple estimation of measurement uncertainties of the parameters is not sufficient to assess the uncertainty of the result. In this paper, an example of a pH measurement conducted using an ion-selective...

A common technique applied during an assay is averaging several repeated measurements in order to obtain a more accurate result. This approach is suitable for most applications. However, in the case of impulsive disturbances which affect the measured object, averaging is not optimal. In the paper, the properties of impulsive disturbances are descri...

The paper deals with the problem of ion activity determination for a mixture by means of ion-selective electrodes. Mathematical model of the analysed phenomenon is described by the Nicolsky-Eisenman equation, which relates activities of ions and ion-selective electrode potentials. The equation is strongly nonlinear and, especially in the case of mu...

Determination of pH using a typical glass electrode requires prior calibration in order to determine the electrode parameters. Knowledge about uncertainties of the parameters is insufficient to calculate the uncertainty of measured pH because of existing correlation. In the paper, an example illustrating the problem is presented. Two ways of proper...

The commented article has introduced to metrology a new way of lowering the uncertainty assessed using Type B evaluation. The proposed method operates properly under some assumptions but unfortunately, the idea has been presented with some understatements and mistakes. The weak points are shown and discussed in this article.

This paper presents a research installation for developing flow measurements in open channel. A tracer technique is used where sodium chloride is applied as a tracer and a conductometric cell as a tracer sensor. Properties of the applied electrical measuring circuit, the ways of determining tracer transit time, flow rate and flow velocity are descr...

In this paper a novel calibration procedure for the parameter determination of ion-selective electrodes used in an array is described. Commonly used procedures require a large number of standards to determine the parameters based on the Nicolsky-Eisenman model. The elaborated procedure reduces the number of standards to a minimum by using a standar...

In the paper, the evaluation of uncertainty in concentration measurement based on the cause and effect diagram is presented. Two methods of evaluating the uncertainty of calibration parameters of ion-selective electrode are compared: the GUM method and the Monte Carlo method. Values obtained in examples are very similar. Small differences are visib...

Measured values of dynamic parameters of ion-selective electrodes are dependent i.a. on the research methods applied due to difficulties in the proper realization of the ion activity change at the electrode membrane. In the paper, the new measuring set-up, realizing the activity step, is presented. Two jets, controlled by the electric valves, throu...

The relationship between the potential E of the ion-selective electrode and ion concentration c are presented in the paper – eqs. (1) – (5). The operations needed to prepare an activity standard, basing on eqs. (7) – (10), are listed and an example is given, haw to make it. Basing on eq. (11), linking concentration c, mass of salt m* and volume of...

The response time of ion-selective electrodes (ISEs) is especially essential when measurements are performed for diluted solutions. The time needed to archive the steady-state E2 can be measured in minutes. The developed algorithm shorten the time significantly by using the estimated value of E2. The dynamic error is then reduced 2-6 times, dependi...

The plot of ion-selective electrode's potential vs. ion concentration in a solution is non-lineax and very complex. In the paper, a set-up is described which allows to determine the plot using multiple dilution method in an automatic way. The set-up is not expensive and the presence of experimenter in the laboratory is not necessary during the test...

Dynamic models of an ion-selective electrode are analysed in this article taking into account the independence of values of its dynamic parameters from the value and direction of activity change. Unfortunately, a complicated mathematical representation of a new model makes the model difficult to be applied in practice. Therefore, some simplificatio...