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101.
Advanced technologies and modern high-production machines for underground mining of thick gently dipping coal demand strict adherence to technological discipline, reduction in operational loss and selection of optimized ventilation modes. The authors analyze ventilation schemes used in working areas in thick gently dipping seams in order to reveal influence exerted by the schemes, methods and parameters of ventilation on distribution of air loss in mined-out areas. 相似文献
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Semiconductors - The optical properties of dielectric nanostructures strongly depend on dielectric nanoparticles (NP) polarizability which can take the high values even interacting with... 相似文献
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Alice Maurer Prof. Dr. Florian P. Seebeck 《Chembiochem : a European journal of chemical biology》2020,21(20):2908-2911
Ergothioneine has emerged as a crucial cytoprotectant in the pathogenic lifestyle of Mycobacterium tuberculosis. Production of this antioxidant from primary metabolites may be regulated by phosphorylation of Thr213 in the active site of the methyltransferase EgtD. The structure of mycobacterial EgtD suggests that this post-translational modification would require a large-scale change in conformation to make the active-site residue accessible to a protein kinase. In this report, we show that, under in vitro conditions, EgtD is not a substrate of protein kinase PknD. 相似文献
105.
ABSTRACTIn recent times, the applications of multimedia are rising in a greedy mode and hence the amount of video transactions is also increasing exponentially. This has shouted great demands on effective models on video encoding and also for reducing the transmission channel congestion. This research work introduces a managing technique termed weighted encoding for High-Efficiency Video Coding (HEVC). HEVC, also termed as MPEG-H Part 2 and H.265 is a video compression standard that is widely utilized AVC (H.264 or MPEG-4 Part 10). When compared to AVC, HEVC grants double the ratio of data compression at a similar level of quality of the video or considerably enhanced video quality at a similar bit rate. This work intends to optimize the weight that adopted in HEVC for encoding. For this, this paper proposes a new Iterative based propagation update in the water wave Optimization Algorithm (IPU-WWO), which is the improved form of Water wave Optimization (WWO). The performance of proposed IPU-WWO is compared over other conventional methods like Artificial Bee Colony (ABC), Firefly (FF), Particle Swarm Optimization (PSO) and Genetic Algorithm (GA) with respect to Peak Signal to Noise Ratio (PSNR). By doing the encoding process, it minimizes the video size with perceptually better quality video or PSNR. 相似文献
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V. A. Grechishnikov Yu. E. Petukhov P. M. Pivkin A. V. Isaev V. B. Romanov V. A. Kosarev A. S. Babaev A. A. Ershov 《Russian Engineering Research》2020,40(1):70-72
The shaping of the toroidal cutting section of end mills is considered. Methods are devised for selecting the positional parameters in shaping the helical rake surface on the toroidal section. Relations are established between the geometric parameters of the end mill in the toroidal section. 相似文献
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The main factors that determine the uniformity with which smelting products are tapped from a blast furnace are the rate of accumulation of the products in the hearth and the tapping rate. The first parameter is in turn determined by the stability of the furnace’s operation and can vary significantly even over the course of 24 h. The second parameter is determined mainly by the condition of the iron notch, the maintenance it receives, any changes that occur in the diameter of the channel of the notch, and the quality of the materials used to form the notch. Recommendations are presented to optimize tapping of the smelting products. 相似文献