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Recent outstanding results of supervised object detection in competitions and challenges are often associated with specific metrics and datasets. The evaluation of such methods applied in different contexts have increased the demand for annotated datasets. Annotation tools represent the location and size of objects in distinct formats, leading to a lack of consensus on the representation. Such a scenario often complicates the comparison of object detection methods. This work alleviates this problem along the following lines: (i) It provides an overview of the most relevant evaluation methods used in object detection competitions, highlighting their peculiarities, differences, and advantages; (ii) it examines the most used annotation formats, showing how different implementations may influence the assessment results; and (iii) it provides a novel open-source toolkit supporting different annotation formats and 15 performance metrics, making it easy for researchers to evaluate the performance of their detection algorithms in most known datasets. In addition, this work proposes a new metric, also included in the toolkit, for evaluating object detection in videos that is based on the spatio-temporal overlap between the ground-truth and detected bounding boxes.

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This work focuses on the characterization of indoor hybrid power line communication (PLC)-wireless channels in the frequency band between 1.7 and 100 MHz. These hybrid channels allow the simultaneous exploitation of the ubiquitous PLC channel and the mobility benefits offered by the wireless signals radiating from and being induced into power cables. A comprehensive study and analysis was conducted based on: (i) coherence time, (ii) additive noise power spectral density, (iii) coherence bandwidth, (iv) delay spread, (v) average channel gain, (vi) channel frequency response and (vii) channel capacity. Based on the reported analysis, the magnitude responses of hybrid PLC-wireless channels can be assumed to be symmetrical and significantly frequency selective. Also, we reveal that additive noise power spectral density and, consequently, channel capacity differ considerably in the PLC-to-wireless and wireless-to-PLC transmission directions. Finally, we show that the measured PLCwireless channels present a channel capacity of up to hundreds mega bits per second.

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