A fractional-order current-controlled memristor pinched hysteresis loop area is calculated in this study. The area is divided into two parts: one equals to the half of instantaneous power and the other is the part memory of the memristor. Moreover, two parts of the area are affected not only by the cosine components, but also by the sine components. The voltage of the fractional-order current-controlled memristor is no longer an odd function with respect to time and the coefficient of cos(ωt) in its Fourier series is zero. In a closed loop, the average power and the memory rely only on sine harmonics of the voltage. Meanwhile, the power and the memory are related to the order of the fractional-order derivative.

The authors propose and demonstrate the fluorescence imaging of green fluorescence protein (GFP) expressed in a brain slice with a self-reset complementary metal–oxide–semiconductor image sensor under background light. By using a self-reset function to avoid pixel saturation, the weak fluorescence of GFP was successfully observed, even under background light. The result suggests that the sensor can be applied to in vivo imaging of laboratory animals during light–dark cycles, so that they can observe the different responses to bright and dark environments.

Maximum power point tracking is a mature control issue for wind, solar and other systems. On the other hand, being a relatively new technology, detailed discussion on power tracking of hydrokinetic energy conversion systems are generally not available. Prior to developing sophisticated control schemes for use in hydrokinetic systems, existing know-how in wind or solar technologies can be explored. In this study, a comparative evaluation of three generic classes of maximum power point scheme is carried out. These schemes are (a) tip speed ratio control, (b) power signal feedback control, and (c) hill climbing search control. In addition, a novel concept for maximum power point tracking: namely, extremum seeking control is introduced. Detailed and validated system models are used in a simulation environment. Potential advantages and drawbacks of each of these schemes are summarised.

The authors validated a novel optical fibre intrusion sensor proposal based on Lefevre-loop and bidirectional polarisation optical time-domain reflectometer technique. Disturbances along 5 m fibre section inside 9 km perimeter were localised within 18 m resolution.

The importance of image processing is increasing in the digitally connected world due to its numerous applications in various fields of medical science, astronomy, weather prediction and video surveillance systems etc. The latest research and development in this field has helped the authors to obtain finer details of a particular image under study. The image segmentation technique, a part of digital image processing, helps to obtain meaningful information of the object. This study discusses the three widely used important image segmentation techniques: namely, split and merge, image growing and thresholding and their effects on a sample image. The authors results thus depict a significant difference in the segmented image by split and merge, image growing and thresholding. Split and merge is the optimal method of image segmentation as compared with the other two techniques mentioned above. The choice of the method varies with type of image, its colour, intensity and noise level.