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According to current algorithms for rotating machines largely depending on expert prior knowledge, this paper proposed an adaptive fault recognition algorithm based on shift invariant dictionary learning and sparse coding. Firstly, it segmented and smoothed vibration signals to decrease the complexity. Then, it used shift invariant dictionary learning with adaptive penalty factor to learn shift invariant bases in different fault states. After that, it used an efficient sparse coefficient solver called feature sign search for reconstructing signal to be recognized. Lastly, residual was an evidence to determining fault state the signal belonging to. In the experiments of rolling bearing datasets and vibration signals of real aero-engine demonstrate its higher accuracy than up-to-date algorithms and feasibility for practical applications. [ABSTRACT FROM AUTHOR]

Heat stress is well recognized as a major biotic stress that severely limits plant growth worldwide. In particular, high temperature is a main limiting factor in the production of vegetable industrialized seedlings raising in summer. Optimal and stable temperature is an important factor for plant growth and metabolism. Tomato is thermophilic, but it cannot withstand high temperature. Hence, how to lower the temperature is an urgently problem that needed to be solved. The low temperature at high altitude localities provided an opportunity to develop the vegetable industrialized seedlings raising production in summer. Raising vegetable seedlings at high altitude is more economical compared with some cooling methods (e.g., forced ventilation, fan/pad system, mist/fog system, roof cooling, mechanical cooling technology system, aquifer coupled cavity flow heat exchanger system, and earth-to-air heat exchanger system) depending on energy consumption. Furthermore, it also provided a new direction to select a suitable location for vegetable industrialized seedlings raising. The objective of this study was to investigate the temperature suitability of the summer alpine seedlings and the effects of high-altitude temperature on tomato seedling growth. During 2016 and 2017, several experiments were performed within four cropping seasons using tomato (Solanum lycopersicum L. Roller) seedlings in the same type of plastic greenhouses at two altitudes, respectively at high (998 m) and low (98 m). Then, temperatures of the alp and plain were measured during tomato seedlings growth. In addition, temperature characteristics were analyzed using the temperature suitability model and run-length theory. Finally, the relationship between air and root-zone temperature and tomato seedling growth were determined by path analysis. In summary, the results showed that the average air and root-zone temperature of night at high altitude significantly (P<0.05) decreased by 16.14% and 18.99%, respectively, in comparison to the plain. More importantly, the average duration of daily maximum temperature decreased by 7.74h at alpine greenhouse in comparison to plain greenhouse. Consequently, raising tomato seedlings at alpine greatly alleviated the damage of high temperature on seedlings. The temperature suitability and temperature unsuitability were 163.64% (daytime+nighttime+root-zone) and 13.34% (daytime+nighttime+root-zone) at high altitudes, which increased by 2.23-fold and decreased by 88.73%, respectively, in comparison to the plain. Furthermore, compared to the plain, the whole plant dry weight, and the seedling healthy index of 28-days-old tomato seedlings growth at high altitude were significantly (P<0.05) increased by 1.39-fold, 1.34-fold, respectively, the soluble sugar content and root vigor significantly (P<0.05) increased by 37.91% and 65.42%, respectively. The day temperature suitability had an extremely significant correlation with the plant dry weight (r=0.774) and shoot dry weight (r=0.773).The night temperature suitability had extremely significant correlation with the root/shoot ratio (r=0.934) and root dry weight (r=0.808), respectively. Compared with the plain, tomato seedlings grown at high altitude had a significant lower flowering node position, and increased numbers of flowers, fruit and fruit set rate after transplanting. In conclusion, this study indicated that raising tomato seedlings at high altitude is an effective method to alleviate high temperature stress and promote tomato seedling growth during summer season. [ABSTRACT FROM AUTHOR]

随着医学检验技术教学的不断改革与创新，虚拟仿真实验教学已成为教师的重要教学手段，各医科院校里的虚拟仿真实验教学中心也成为医学检验技术信息化的重要组成部分，如何实现医学检验技术虚拟仿真实验教学中心的可持续发展是一项重要的任务。通过对医学检验技术虚拟仿真实验教学中心的现状进行梳理，分析影响虚拟仿真实验教学中心可持续发展的问题和制约的因素，提出可持续发展的资源利用与开发举措，以及以知识产权保护体系、经费保障机制、长效激励机制为主体的管理体系和运行机制。 [ABSTRACT FROM AUTHOR]