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Ship target detection based on video surveillance has an important application in maritime security. In order to reduce the interference caused by the complex marine environment, it is usually necessary to preprocess the captured images. Based on the current research results of ship video detection at sea, this paper summarizes the commonly used ship target detection preprocessing methods under visible light detection conditions, including: image format conversion, video image anti jitter, defogging processing, image filtering, binary processing and morphological filtering. On this basis, the development of pretreatment technology and the research and development strategy of ship target detection system are discussed.

The paper reports that the light-scattering property of ZnO nanorods (NR) can be improved significantly in the near-UV/blue light region by Mg-doping. The NR were prepared using the hydrothermal method then characterized by scanning electron microscopy (SEM), X-ray diffraction, UV–Vis spectrophotometry. The results indicated that the average diameter and length of the NR reduced while the transmittance, band gap and light-trapping ability increased after the Mg-doping. The MgZnO NR shows significantly strong light-scattering parameter (average haze = 79.06%) over the undoped ZnO (43.29%) from 300 to 430 nm. This method presents a facile way for adjusting the light-trapping ability for ZnO thin films and the ZnO-based shortwave devices.

The properties of Al-doped ZnO (AZO) play an important role in the photovoltaic performance of inverted polymer solar cells (PSCs), which is used as electron transport and hole blocking buffer layers. In this work, we study the effects of Al-doping level in AZO on device performance in detail. Results indicate that the device performance intensely depends on the Al-doping level. The AZO thin films with Al-doping atomic percentage of 1.0% possess the best conductivity. The resulting solar cells show the enhanced short current density and the fill factor (FF) simultaneously, and the power conversion efficiency (PCE) is improved by 74%, which are attributed to the reduced carrier recombination and the optimized charge transport and extraction between AZO and the active layer.

In this work, gradient Al-doped ZnO multi-buffer layers (MBLs) were used as the electron transport layers (ETLs) of organic solar cells (OSCs) for the first time. Three kinds of MBLs were prepared using a facile sol–gel process and deposited on a homo-buffer layer (ZnO). Compared to a device based on a multi-ZnO buffer layer, devices with the gradient-doped MBL displayed enhanced power conversion efficiency from 2.11% to 3.43%, which were caused by the efficient light transmission and charge carrier transport, derived from the higher film qualities, denser and more uniform surface morphologies, and improved conductivities of the gradient-doped MBLs. Results indicated that a device with ZnO/MBL (0.5:1.0 at%(Al/Zn)) simultaneously enhanced the short-circuit current and fill factor. This study presents an innovative and effective method for improving the quality of ETLs for efficient OSCs.

Al-doped ZnO (AZO) has been used as an electron transport and hole blocking buffer layer in inverted organic solar cells (IOSCs). In this paper, the AZO morphology, optical and structural properties and IOSCs performance are investigated as a function of precursor solution concentration from 0.1 mol/L to 1.0 mol/L. We demonstrate that the device with 0.1 mol/L precursor concentration of AZO buffer layers enhances the short-circuit current and the fill factor of IOSCs simultaneously. The resulting device shows that the power conversion efficiency is improved by 35.6% relative to that of the 1.0 mol/L device, due to the improved surface morphology and transmittance (300–400 nm) of AZO buffer layer.

The cosmological redshift phenomenon can be described by the dark matter field fluid model, the results deduced from this model agree very well with the observations. The observed cosmological redshift of light depends on both the speed of the emitter and the distance between the emitter and the observer. If the emitter moves away from us, a redshift is observed. If the emitter moves towards us, whether a redshift, a blueshift or no shift is observed will depend on the speed vs. the distance. If the speed is in the range of c(exp[-beta*D]-1) < v < 0, a redshift is observed; if the speed equals c(exp[-beta*D]-1), no shift is observed; if the speed v less than c(exp[-beta*D]-1), a blueshift is observed. A redshift will be always observed in all directions for any celestial objects as long as their distance from us is large enough. Therefore, many more redshifts than blueshifts should be observed for galaxies and supernovae, etc in the sky. This conclusion agrees with current observations. The estimated value of the redshift constant beta of the dark matter field fluid is in the range of 10^(-3) ~ 10^(-5)/Mpc. A large redshift value from a distant celestial object may not necessarily indicate that it has a large receding speed. Based on the redshift effect of dark matter field fluid, it is concluded that at least in time average all photons have the same geometry (size and shape) in all inertial reference frames and do not have length contraction effect., 11 pages, 1 figure