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During the thermoplastic forming of TC4 alloy parts, the surface of TC4 alloy billets will be severely oxidized, so it is necessary to prepare anti-oxidation lubrication coating on the surface of billets. By comparing the standard free energy of formation of TiO2 and taking the intermediate value of mass percentage of the corresponding oxide in some literatures, the appropriate oxides such as 44.0% SiO2, 25.0% B2O3, 10.0% Na2O, 7.5% CaO, 6.8% MgO, 1.7% Al2O3 and 5.0% TiO2 were selected to prepare the borosilicate glass powder with high temperature solid-state reaction method. Then, the glass coatings with thickness of 0.15-0.3 mm were prepared on the surface of ϕ17.5 mm × 7.5 mm TC4 alloy cylindrical samples, by dip coating method with the glass powder. It is found that the glass coating has excellent high temperature oxidation resistance by oxidation experiments holding for 2 hours at different temperatures from 500 to 1050 °C. The observations of surface morphology and phase of the glass coating by SEM and XRD found that the glass coating particles with holes between each other, began to melt into amorphous phase at 650 °C. With the increase of temperature, especially above 850 °C, the glass coating gradually melted into a compact film composed of CaMgSi2O6 and a small amount of CaMg(SiO3)2 or Na(AlSi3O8). It can tightly enwrap the substrate and physically isolate oxygen from the furnace gas, so can effectively prevent TC4 billets from oxidation in the range of hot working temperature.

The 8-sliding puzzle game, with its characteristic, is beneficial to human logical training and well-known single-agent game worldwide. This study is interested in determining the attractiveness of the game by analyzing the inner mechanism of the game. By adopting total steps to solve the game and the success rate as the game progress model, the game sophistication can be quantified by utilizing the game refinement theory and law of motions in mind. The game's sophisticated zone, engagement, movement freedom, and entertainment depths for different levels of player can be determined for both AI (via A* algorithm) and human players. The 8-sliding puzzle game was also analyzed as a board game and sports game for its attractiveness. Such findings could contribute to the evolutionary changes in the sliding puzzle games.

Key generation is a promising technique to bootstrap secure communications for the Internet of Things (IoT) devices that have no prior knowledge between each other. In the past few years, a variety of key generation protocols and systems have been proposed. In this survey, we review and categorise recent key generation systems based on a novel taxonomy. Then, we provide both quantitative and qualitative comparisons of existing approaches. We also discuss the security vulnerabilities of key generation schemes and possible countermeasures. Finally, we discuss the current challenges and point out several potential research directions., Comment: 35 pages, 5 tables, 6 figures