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Sources have been described of corrosively hazardous electric fields and methods of determination of the corrosion hazard to metal structures caused by electrolytic corrosion. Results of potential and impedance investigations in the field of stray currents flowing out of a tram traction and in the presence of a defined electric field of low frequency have been presented. Uncertainties have been indicated relating to the generally accepted interpretation principles of measurement results in the presence of electric fields. The possibility has been indicated of incorporating the impedance spectroscopy technique to potential‐voltage investigations, allowing estimation of the real corrosion interaction of stray currents on underground structures.

This paper sets out to detect and characterize electric fields in the ground (such as stray current fields) using a tandem time/frequency method of signal analysis.

Results were obtained from investigations performed in the presence of a generated electric field with controlled variable characteristics, and in the presence of an electric field generated by a tramline. The analysis of measurement registers was performed using Short‐Time Fourier Transformation. The results were presented in the form of spectrograms, which illustrate changes in the spectral power density of the measured signal versus time.

Tandem time/frequency analysis reveals the random or deterministic character of the electric field, enabling its complete time/frequency characteristics to be obtained. Such information is inaccessible using exclusively the frequency analysis methods that utilize classical Fourier transformations. Moreover, an analysis of the spectral power density distribution of the signals in three directions on the ground surface makes it possible to define the localization of the field source.

Analysis methods for electric fields in the ground should be adapted to the evaluation of non‐stationary signals because the stray currents are of this type. Such a possibility is given by combined analysis in the domains of time and frequency. This method can be used as complementary to applied measurement techniques of stray current interference.

The method of electric field detection and characterization, as related to stray currents, previously has not been presented in the literature. This method of signal analysis may be adopted for other investigations that are reliant on the registration of voltages or potentials characterized by arbitrary frequencies.

The purpose of this paper is to investigate whether the sedimentation of calcareous deposits occurs on cathodically protected steel in Baltic sea water.

Steel electrodes were cathodically polarized in natural Baltic sea water at potential +0.150 V vs Zn electrode in potentiostatic mode. During exposure chronoamperometric measurements were carried out. After the exposure, the electrode's surface was examined by scanning atomic force microscope (AFM) and by scanning electron microscope (SEM). Deposit composition was examined by energy‐dispersive X‐ray spectroscopy (EDX). Comparative investigation was carried out in 1 percent NaCl solution (comparable to the salinity of Baltic sea water).

During cathodic polarization in Baltic sea water, non‐conducting calcareous deposits developed on steel surface. These deposits significantly lowered the cathodic current demand. Morphology and EDX spectroscopy of the deposit indicated that it was built mainly of aragonite (polymorph of CaCO3). No non‐conducting deposits on cathodically protected steel electrodes developed in 1 percent NaCl solution.

Composition of Baltic sea water favours the formation of calcareous deposits on cathodically protected steel. Sedimentation is a beneficial and desired phenomenon from the point of view of cathodic protection system of maritime construction as it facilitates polarization. Evolution of calcareous deposits should be taken into account as one of the environmental factors when designing a cathodic protection system.

The purpose of this paper is to detect the source of stray current interference on underground pipelines in urban areas using a joint time/frequency method of signal analysis.

Investigations are performed on an underground pipeline located in the vicinity of the two direct current tractions: a tramway line and a train line. The results of the analysis are presented in the form of spectrograms, which illustrate changes in the spectral power density of the potential of the rails and of the potential of the pipe in the joint domain time‐frequency.

The comparison of the spectrograms can be used to evaluate if and which stray current source has influence on the investigated metal construction.

The combined analysis in the domain of time and frequency can be used as a supplementary one providing new information useful in the evaluation of stray current corrosion hazard. In the presence of several electric field sources in urban areas, this method reveals the complete time‐frequency characteristic of each stray current source and its interference on the investigated construction.

The aim of this paper is to present the modernization of an old cathodic protection system installed on the legs of an offshore platform and to discuss the results of the research performed in order to investigate the anticorrosive effectiveness of this solution.

The modernization of the cathodic protection system consisted of connecting to the platform legs a sacrificial anode system placed at the sea bottom. The effectiveness of the modernized system was assessed on the basis of the measurements of the potential profiles of the platform legs, i.e. the distribution of their potential over the entire length.

After connecting sacrificial anode systems, the potential of the legs kept changing towards more negative values. The extent of cathodic polarization increased, and already after a week the potential of the legs fell within the range of full cathodic protection almost along their entire length. The polarization was higher at the lower parts and decreased close to the water surface, which was a result of the distance of a given fragment from the anodic system. The results of the measurements confirmed the correctness of the design assumptions and the effectiveness of the performed modernization.

The results obtained show that the modernization of the cathodic protection system on the legs of an offshore platform consisting of connecting sacrificial anode systems placed at the sea bottom can ensure the achievement of full cathodic protection potential for long legs (these were 80 m long in this study).

Results of investigations on a working cathodic protection installation of two underground LPG tanks are presented. The efficiency of anodes and buried reference electrodes were evaluated using electrochemical impedance measurements. On the basis of the impedance spectra obtained it can be shown how one of the anodes attached to the long anode line works inefficiently. In addition, the potential distribution map for the protected tanks is presented. On the basis of this information, an electric connection was revealed from the tanks to the neighbouring reinforced concrete structures, this being inconsistent with the technical guidelines for the cathodic protection installation. The inspection performed on the installation yielded some recommendations concerning the operational parameters and the identification and replacement of defective components.

The purpose of this paper is to predict quantitative level of stray current leaking to the buried metallic structure by establishing convolution neural network (CNN) model.

First, corrosion experimental system of buried metallic structure is established. The research object of this paper is the polarization potential within 110 min, CNN model is used to predict the quantitative level of stray current leakage using the data from corrosion experimental system further. Finally, results are compared with the method using BP neural network.

Results show that the CNN model has better predictive effect and shorter prediction time than the BP model, the accuracy of which is 82.5507 per cent, and the prediction time is shortened by more than 10 times.

The established model can be used to forecast the level of stray current leakage in the subway system effectively, which provides a new theoretical basis for evaluating the stray current corrosion hazard of buried metallic structure.

The purpose of this paper is to analyze and estimate the stray current corrosion hazard of a buried metallic pipeline using a predictive model for stray current density.

A predictive model for stray current density of the buried metallic pipeline was built, using a back propagation (BP) neural network method and experimental data. The accuracy of the model was tested using test samples. The single sensitivity analysis predictive method was used to establish the relationship between stray current density with the soil resistivity. The effects of buried depth and the pipe‐to‐ground voltage offset were researched using this network model.

The feasibility of the BP neural network to forecast stray current effects from the buried metallic pipeline was confirmed.

The paper provides a new method to analyze and estimate the stray current corrosion hazard of buried metallic pipelines.

The purpose of this paper is to understand the role of perceived threat, brand congruence, and social support on consumer coping strategies for a preventative health service.

An online survey of 570 women aged over 50 in one Australian state was conducted (users and non-users of the service). The data were analyzed using structural equation modeling.

A competing models approach reveals that threat on its own is associated with avoidance coping; however, when brand congruence is high, there is an association with active coping. Social support appears to have a buffering effect on threat and is associated positively with active coping and negatively with avoidance coping.

The study findings suggest that threat appeals should be used with caution in increasing participation in transformative preventative health services due to its double-edged sword effect (increasing both avoidance and active coping). When consumers have social support, this results in active coping and buffers avoidance coping. This research offers useful insights for social marketing and transformative service research.