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Nonlinear loads have become more prevalent in all applications, including computers, transformers, and adjustable speed drives. The harmonic level of the underground distribution cables rises as a result of these loads. As a result, the cable layers' temperatures are affected by the harmonic levels. The purpose of this paper is to calculate the temperature distribution of a cable conductor and the soil around it under cyclic loading conditions, including the impact of linear and nonlinear loads. The IEC 60,853-2 standard is used to consider the thermal model of an underground cable. The finite element method is investigated to obtain a heat map of the cable layers and their surrounding soil. In this study, the small-scale model was constructed in the laboratory. The cable is installed using two methods at the same loading conditions. The heat transfer in the four-core low-voltage cable installation is measured. Furthermore, total harmonic distortion is measured using a Fluke 125 scope meter. The experimental results from the laboratory model proved that there was an extreme increase in the temperature of cable layers when the cable was installed inside the polyvinyl chloride duct in the soil compared with its installation directly buried in the soil. The results of the experimental tests are compared with simulation results.

A study of the performance of power cables installed inside non‐metallic ducts is presented here. Cable capacity calculations for this type of installation are done. The thermal analysis of cables inside ducts which are installed in air as riser or buried in soils is presented. According to IEC 60287 cables can be installed in fibre ducts in concrete layer surrounded by the soil, in this article it is proposed to install the cables in PVC ducts directly buried in the soil. Based on IEC 60287‐1‐3 and IEC 60853‐2 standards proposed models in steady state and dynamic cable loadings are constructed. The proposed equivalent thermal models are used in the calculations of the cable components temperature for cables installed in ducts. It is concluded that very high increase in cable conductor temperature is observed when the cable is installed in duct and used as riser or even when it is installed in duct buried in soil. Significant decrease in the temperature of the cable conductor can be noticed when the cable is directly buried in the soil compared with that installed in ducts.

Observing network traffic is necessary for achieving different purposes such as system performance, network debugging and/or information security.Observations, as such, are obtained from low-level monitors that may record a large volume of relevant and irrelevant events. Thus adequate filters are needed to pass interesting information only. This work presents a filtering mechanism that acquirs the intersting packets from the underlying network due to the user specifications. The packets are acquired according to specific grammar rules, and they are preserved in an observation file called log-file.