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Graphene oxide/epoxy composite coatings have attracted much attention from researchers due to their excellent anti-corrosion properties. Graphene oxide as a two-dimensional nano-filler can enhance the overall properties of epoxy resin coatings. In the paper, models of graphene oxide/epoxy composite coatings with different permeation degrees are constructed respectively. The interfacial interaction between GO and epoxy resin and the adsorption properties of epoxy coating with metal are analyzed from an atomic perspective by molecular dynamics simulations. The results indicate that the interfacial adsorption effect of the epoxy coating on the protected metal is stronger than the interfacial bonding of GO on the epoxy resin matrix. Simulations of models with different degrees of permeation suggest that the permeation of the NaCl solution occupies the interfacial space and reduces the adhesion between the two interfaces.

Flourishing green hydrogen economy worldwide serves as a pillar for global energy transition and carbon-neutral targets. However, rare researches on the environmental impact of green hydrogen production have focused on national average resource availability and technology market share. Nor a detailed and holistic sensitivity and uncertainty analysis regarding both foreground and background parameters in the green hydrogen production life cycle could be found. To fill these gaps, we present this study as a comprehensive environmental impact investigation of renewable-electricity-based water electrolysis H2 production in France, in terms of average resource availability and technology market share in France in 2019. Water electrolysis H2 production with average French wind electricity through proton exchange membrane electrolysis unit was identified as the most environmentally-beneficial option among all pathways studied. By building the corresponding French national benchmark parametric life cycle model, the key parameters that determine the environmental impact of green hydrogen in France were revealed. Under current French context, environmental impact’s uncertainty for solar-to-H2 and wind-to-H2 pathways is between 19%-26% and 8%-11%, respectively. Based on the unit process contribution investigation and further scenario analyses, we propose the guidelines and suggestions on improving life cycle renewability and sustainability to French green H2 production.

Food production involves both agricultural and industrial activities which consume several resources among which: water, energy, land, minerals and chemicals. The efficiency in the use of the resources depends on the type of food which is produced and the adopted processes. In any case if food is discarded or lost at any step of the supply chain this represents a waste of energy and resources. For this reason, the LIFE project irexfo, coordinated by the University of Perugia has proposed a way to promote a business model aiming at both: the reduction of food losses and also the reuse of the not comestible food waste in biogas plants. The model has been tested in Umbria as a pilot region and in this study the results obtained are scaled up to a national level and applied to the Italian IO database reported in the EXIOBASE, to evaluate which could be the benefits of the application of the irexfo business model to the whole Italian agroindustry sector and also the interrelations between this sector and the Italian energy sector. The analysis is performed using SimaPro software 9.0, results are compared with those of similar studies which have been performed at European level. This is the first study of this kind focused on Italy.

This paper proposes an assumption that filtering out the confusing “awake” data from fatigue driving detection model promotes the accuracy of detection of “drowsy” status under real driving situation. Instead of focus on both “drowsy” and “awake” driving status, we set our first priority to alarm “drowsy” and temporarily ignore the accuracy of “awake” status recognition. The Support Vector Machine as a good classifier is employed for data filtering, provides more efficient training data and removes the data that may confuse the detection model. The results prove our assumption by 72% accuracy on “drowsy” recognition, which is higher than 38% recognition performed by detection without SVM filtering. In addition, the size of training samples after filtering for conducting detection model is extremely smaller than no filtering.

The C3I cooperative decision system is the guarantee for combat capabilities of surface warship formations. At present, research on the C3I system simulation lays more emphasis on finding structural logic defects by executing the simulation model, lacking the application of intelligent optimization algorithms to optimize parameters in the system. In this paper, the cooperative decision-making process of surface warship formation defense system is studied. Meanwhile, modelling and optimization methods for cooperative decision system are proposed. Based on simulation models built on the ExtendSim platform, this paper optimizes the staffing strategy of decision makers based on the genetic algorithm, to improve the per capita decision efficiency. The optimized staffing strategy meets objectives and requirements. The research in this paper can provide a scientific and objective reference for relevant decision-makers and researchers.

PPP mode is widely used in urban garbage disposal projects. The key to success is to allocate PPP project risk reasonably and effectively. The paper firstly constructs a PPP project operation system of urban garbage disposal, and then the risk identification and the main sharing agents are analyzed. On the basis of the utility theory, the risk preference of each agent is considered, and the profit and cost efficiency function of the three agents, including investor, the government and the financial institutions is established. Finally, the function model is applied by a case of urban garbage disposal PPP project. The result shows that the proportion of risk sharing is related to the risk preference of each agent, and the optimal risk sharing proportion may make the overall utility of the project optimal.

This paper presents a personalized course recommended algorithm based on the hybrid recommendation. The recommendation algorithm uses the improved NewApriori algorithm to implements the association rule recommendation, and the user-based collaborative filtering algorithm is the main part of the algorithm. The hybrid algorithm adds the weight to the recommendation result of the user-based collaborative filtering and association rule recommendation, implementing a hybrid recommendation algorithm based on both of them. It has solved the problem of data sparsity and cold-start partially and provides a academic reference for the design of high performance elective system. The experiment uses the student scores data of a college as the test set and analyzes results and recommended quality of personalized elective course. According to the results of the experimental results, the quality of the improved hybrid recommendation algorithm is better.

Femtosecond laser microfabrication has been recently utilized in interface science to modify the liquid wettability of solid surfaces. Silicon surface with hierarchical micro/nanostructure is fabricated by a femtosecond laser. Similar to the fish’s scales, the laser-induced surface shows superhydrophilicity in air and superoleophobicity underwater. The oil contact angles can reach up to 159.4 ± 1° for the 1,2-dichloroethane droplets in water. Besides, the surface exhibits ultralow oil-adhesion. In the oil/water/solid three-phase system, water can be trapped in the hierarchical rough structure and forms a repulsive oil layer according to underwater Cassie’s theory. The contact area between the asprepared surface and oil droplet is significantly reduced, resulting in superoleophobicity and ultralow oil-adhesion in water. In addition, transparent underwater superoleophobic and anti-oil surfaces are achieved on silica glass surfaces by femtosecond laser ablation. This transparent property is attributed to the presence of the water environment because scattering and refraction are effectively weakened. The presented method is simple and can accurately control the processing location, which may have widely potential applications in, for instance, microfluidics, biotechnologies, and antifouling coatings.

We studied, in healthy elderly subjects (aged from 63 to 83 years) and adults (aged from 20 to 32 years), ocular saccades in two conditions: one the one hand, the gap condition, where the central target disappears; then follows a period of 200 ms during which the fixation and attention were disengaged; finally, a visual target appears in the periphery. On the other hand, the overlap condition, in which the peripheral target appears when the central target is still present, the subject should voluntarily disengage his attention and fixation to orient them toward the peripheral target. These paradigms stimulate automatic versus controlled triggering of saccades. The average saccade latency (measured by video-oculography) was longer in the elderly, and irrespectively of the condition. However, the elderly as the young subjects produced shorter latencies in the gap condition than in the overlap condition. Moreover, in the gap condition, we observed the emergence of a considerable number of reflex saccades with very short latency (between 80 and 120 ms, minimal conduction time) called "express saccades". The occurrence rate of such saccades was similar in the young and the elderly subjects. These results suggest the existence of separate circuits, one non-being sensitive to age (express saccades), the other suffering the effects of aging (controlled saccades). In another ongoing study, this methodology has been applied to patients with Lewy body dementia. The preliminary results from three patients showed an abnormal slowness of latencies, even in the gap condition expected to promote automatic and reflex saccades. Furthermore, we observed a total absence of saccades with express latency. These promising results suggest a deficit even for automatic and express saccades in these patients.