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With the continuous advancement of science and technology, the social network based on the Internet has gradually penetrated into people’s daily lives. The image data shared on social media using platforms such as mobile phones has exploded, and hundreds of millions of dollars are generated every day with picture information. In the past, the traditional ways of expressing textual information that people are familiar with have begun to be gradually replaced by image information that is not subject to regional culture such as language and script. In modern warfare, with the continuous development and equipment of highly sophisticated weapons and equipment, the amount of information that the entire combat system needs to process will also increase. In particular, the air defense system needs to quickly and accurately identify the aircraft targets that are coming. It mainly uses computer to extract the feature information of the acquired image and converts the content in the image into a feature expression that can be processed by the computer. After the appropriate classification algorithm, the image is the target object is classified by category. In this paper, we propose a complex image recognition algorithm based on immune random forest model. The experimental results show that the proposed algorithm has high recognition efficiency and higher robustness.

Limestone powder is widely used in concrete for efficient reduction in hydration heat in the place lacking common supplementary cementitious materials. The sodium gluconate and citric acid have been commonly used as retarders to extend the setting time of concrete during summer construction. To study the influence of retarders on hydration and microstructure development of cement containing high-volume limestone powder, multi-technique methods are employed. Isothermal calorimetry, thermogravimetric analysis, X-ray diffraction, mercury intrusion porosimetry and energy-dispersive X-ray analyses in the scanning electron microscopy are used to investigate the hydration process, the content of hydration products, the species of the hydration products, the pore structure of cement pastes and the composition of C–S–H. The results show that the retarders have a better inhibition effect on the hydration of cement containing high-volume powder limestone than on that of cement without limestone powder. At a given dosage, the citric acid has a stronger interaction with the cement containing 30% limestone powder than the sodium gluconate. For the cement containing a high volume of limestone powder, the presence of retarders induces a higher porosity, a larger critical radius and a lower average Ca/Si ratio of C–S–H at 28 curing days. The porosity and the volume fraction pore size smaller than 50 nm have a linear relationship with the hydration degree and the gel/space ratio, respectively. However, the critical radius of cement pastes has an exponential relationship with the hydration degree and gel/space ratio, respectively.

An electro-deposition method has been recently proposed to repair cracked reinforced concrete. To evaluate the corrosion resistance of the reinforcing steel in cracked concrete, three different parameters including type of auxiliary electrode, electrode distance, and current density were studied. Tafel polarization curve was used to evaluate the corrosion resistance of the steel. Self-corrosion potential and corrosion current of the steel were tested. The results indicate that the corrosion resistance improvement of the reinforcing steel is optimal as prism titanium mesh is applied as auxiliary electrode, followed by the flaky titanium mesh and the column titanium bar. When the electrode distance is 60 mm, the corrosion resistance improvement of the reinforcing steel is optimal, and with 80 mm electrode distance, the corrosion resistance improvement is the poorest. The property falls in between them when 40 mm electrode distance is used. Moreover, the corrosion resistance improvement of the reinforcing steel increases as the current density goes up.

We put forward a method of rapid preparation of chloride selective electrode (Ag/AgCl electrode) by dipping silver wire into sodium hypochlorite solution. The electrodes were prepared through different immersion time. The properties of the electrodes, such as Nernst response, response time and long-term stability, were tested in simulated concrete pore solutions (SCPS). Moreover, the surface morphology of the electrodes was also detected after immersion in solutions over three months. The experimental results reveal that the Ag/AgCl electrode with the fabrication time of 20 minutes (E-20) which is recommended to work as the chloride ion selective electrode has the best performance. Compared to that fabricated by the electrolytic process (E-EP), E-20 can be manufactured in mass. The method has almost the same good performance of Nernst response as E-EP, and has a better response time which is less than 25 seconds. The method also shows a better good long-term stability in SCPS containing chloride ions over three months.

To evaluate the effect of pulse parameters on the formation of electrodeposits in concrete cracks, five different types of pulse current were set up, and ZnSO4 and MgSO4 solutions were used as the electrolytes. The rate of weight gain, rate of surface coating, rate of crack closure and crack filling depth were measured. Scanning electron microscopy was used to assess the morphology of the electrodeposits, and energy dispersive spectroscopy was used to analyze the mineral composition of the electrodeposits in the cracks. The experimental results demonstrate that, among five different pulse parameters, when Ton/Toff=0.8 ms/0.8 ms, the healing effect of electro-deposition is the best. The pulse mode hardly affects the mineral composition of the electrodeposits but changes the micromorphology. In addition, for both ZnSO4 and MgSO4 solutions, when Ton/Toff=0.8 ms/0.8 ms, the crystal structure of the electrodeposits is the most uniform and the densest.

Super resolution reconstruction of video image is a research hotspot in the field of image processing, and it is widely used in video surveillance, image processing, criminal analysis and other fields. Super resolution image reconstruction can reconstruct a high resolution image from low resolution images, and this technology has become a research hotspot in the field of image processing. In recent years, deep learning has been developed rapidly in the field of multimedia processing, and image super resolution restoration technology based on deep learning has gradually become the mainstream technology. In view of the existing image super-resolution algorithm problems, such as more parameters, larger amount of calculation, longer training time, blurred image texture, we use the deep self-coding learning method to improve it. We analyze the advantages and disadvantages of the existing technology from the network type, network structure, training methods and so on, and sort out the development of the technology. The experimental results show that the improved network model achieves better super-resolution results, and the subjective visual effect and objective evaluation index are improved obviously, and the image sharpness and edge sharpness are improved obviously.

The influence of Mn2+ ions on the generation of heavy metal anode slime during zinc electrolysis industry was extensively investigated using several electrochemical methods, electron microscope technologies, and particle size analysis. Results showed that the Mn2+ could obviously promote oxygen evolution reaction (OER) and thereby weaken oxidation efficiency of Mn2+ (ηMnO2) and dissolution of Pb2+. The significant improvement in kinetic parameters for OER was found in electrolytes of 1 and 3 g/L Mn2+, but became unstable as the Mn2+ concentration increased to 10 g/L. This result was correlated with much different properties of oxide layers that its changes of microstructure are involved in, since it confirmed that the positive role of compact oxide layers in contributing to high corrosion resistance and activity for OER, but excessive Mn2+, resulted in its micromorphology of overthickness and instability. Such differences resulted from the effect of the Mn2+ concentration fluctuation on kinetic rates of the nucleation growth process. The formation and adsorption of intermediate MnO2-OHads identified as the controlled step for Mn2+ catalyzing OER was also recommended. The generation mechanism of anode slime was found to be changed in essence due to varying Mn2+ concentrations. In electrolyte of 1 g/L Mn2+, results revealed that the root cause of excessive small suspended anode slime (around 20 μm) was the change of the initial pathway of Mn2+ electro-oxidation, whereas, it showed great improvement in the settling performance as the Mn2+ concentration was increased to 10 g/L. Considering the potential of optimizing Mn2+ concentrations as a cleaner approach to control anode slime, deepening the understanding of the impact mechanism of Mn2+ can provide new insights into intervention in the generation of anode slime.

The fabrication of Mg–Al layered double hydroxides (LDHs) intercalated with NO3 −, NO2 − and p-aminobenzoate and comparative investigation on their chloride absorption in aqueous solutions have been performed in this paper. The Mg–Al-LDHs intercalated with NO2 − and p-aminobenzoate were synthesized by anion exchange in the host materials, Mg–Al–NO3 LDH, which was prepared by a coprecipitation method. Also, the equilibrium isotherms of chloride adsorption on the as-obtained LDHs were measured. Besides, their morphologies and microstructures were observed using scanning electron microscopy, X-ray diffraction instrument, infrared spectroscopy and thermal analysis. It has been found that the as-obtained LDHs are well crystallized and have a very large distribution of size. The basal spacing of hexagonal plates is dependent on the types of intercalated anions. Langmuir isotherm is more suitable to fit the experimental data of chloride adsorption than Freundlich isotherm. Compared to Mg–Al–NO3 LDH, the maximum adsorption capacity of chloride is slightly reduced for Mg–Al–NO2 LDH, but remarkably decreased for the LDH intercalated with p-aminobenzoate anions.

A monitoring technique based on the chloride selective electrodes for the chloride content in concrete which is accurate, non-destructive, and continuous would be highly desirable. For this reason, the performance, such as Nernst response and resisting polarization, of the electrode was tested both in simulated concrete pore solutions and concrete. Moreover, the surface morphology of electrode after immersion in solutions over 3 months was detected. Results revealed that the electrode potential showed a good Nernst response with chloride concentration and was affected little by sulfate ion. The detection limit for the chloride concentration was 10−3 mol L−1 at pH 13.5 and 10−4 at lower pH values. In addition, the electrode also had a high exchange current density and a high equivalent capacitance. The Ag/AgCl coating showed good long-term stability over 3 months in solutions containing chloride ions. Besides, there was a good agreement between the free chloride content determined by the electrode and by pore solution expression.

The effect of carbonation on fatigue performance of ground granulated blast-furnace slag concrete was investigated. Based on the static compression tests of carbonated GGBS-concrete, the correlation between carbonation depth and compressive strength was analyzed and an equation between carbonation depth and compressive strength was put forward. Meanwhile, fatigue S-N curves of various carbonation depths were fitted, and the influence of carbonation on fatigue life and strength was studied. Carbonation has a dual effect on the fatigue behavior of GGBS-concrete. A fatigue equation based on the depth of carbonation was established. Also, the probabilistic distribution of fatigue life of carbonated concrete at a given stress level was modeled by the two-parameter Weibull distribution.

Two types of solutions (ZnSO4, MgSO4) were selected to study the influence of mineral admixtures on the electro-deposition healing effect of concrete cracks. Four parameters (i e, rates of weight gain, surface coating, crack closure and crack filling depth) were measured. The mineral composition of electro-deposits in the cracks was analyzed. The study shows that the healing effect of mortar specimens with 10% fly ash is the worst, while the healing effect of mortar specimens with 20% fly ash is better than that of the specimens without fly ash. The rates of weight gain, surface coating, crack closure and crack filling depth decrease with increasing content of the ground granulated blast-furnace slag(GGBS). The mineral admixtures have no influence on the composition of deposits.

The applicability of the rapid iodide migration test was systematically studied. Comparative experimental tests of different test conditions, including several external voltages, test durations, concrete ages and mixing proportions, were carried out to make clear the transport behaviors of iodide under parallel electric fields. Numerical simulations were also done using the finite element method to found the correlation between chloride and iodide transport behaviors. The test and numerical results show that the chloride transport behaviors of RIM and RCM tests have a good correlation under the several conditions used in the present paper. Moreover, the influence of external conditions (external voltages, test durations) on the test results is small. Thus, it can be concluded that the RIM method is available to determine the chloride penetration resistance of the chloride-eroded structural concrete.

With the zinc salt and magnesium salt solutions, the influence of anion types on the electrodeposition healing effect of concrete cracks was investigated, four parameters such as rate of weight gain, surface coating, crack closure, and crack filling depth were measured, and the mineral composition and appearance of electrodeposits in the cracks were analyzed. The experimental results demonstrate that the electrodeposition healing effect is the best by adopting ZnSO4 and MgSO4 solutions. The mineral composition of electrodeposits in the cracks does not change with the anion types. The most particles of ZnO crystal appear as fusiform by using zinc salt solutions. If we selected MgSO4 solution, the Mg(OH)2 crystal was porous honeycomb. The electrodeposits present as flake structure while the other magnesium salt solutions were adopted.

Steel bar corrosion on electrolytes and the influence of cation were investigated. Three electrolytes of Ca(OH)2, NaOH and KOH with pH levels of 12.5, 11.5, 10.5, 9.5, 8.5 were prepared, meanwhile, the methods of free corrosion potential and electrochemical impedance spectra (EIS) were used to evaluate the influence of cations on the depassivation of the steel bar in electrolytes. The experimental results indicate that the initial corrosion pH value of the steel bar is influenced by the cation in electrolyte and the influence of K+ in electrolyte is the most remarkable, followed by Na+ and Ca2+. The initial corrosion pH values are 10.5 in KOH electrolyte, 9.5 in NaOH electrolyte and lower than 8.5 in Ca(OH)2 electrolyte.