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51.
52.
《Journal of the European Ceramic Society》2022,42(4):1332-1340
A new type of high-temperature-resistant SiZrBOC ceramics was prepared by sol-gel method using polymethyl-hydro siloxane (PMHS), boric acid (B(OH)3), and n-propyl zirconate (Zr(OPr)4) as raw materials. After high-temperature pyrolysis, the SiZrBOC precursor was transformed into a crystalline ceramic material with a yield of 89.5 wt%. Fourier infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA) were applied to characterize the polymer-ceramic conversion process and thermal behavior of ceramic precursors. According to the results, the addition of boron elements led to the formation of Si-O-B links in the system. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to study the phase composition and microstructure of SiZrBOC ceramics. Finally, the oxidation test at 1200 °C revealed that SiZrBOC ceramics with a boron/zirconium molar ratio of 2.5:1 exhibited the best oxidation resistance at a weight gain of 0.4 wt% only. 相似文献
53.
胡楠 《电信工程技术与标准化》2014,(7):86-90
如何在节能减排的大背景下,不断开拓新思路、运用新技术,在不影响网络质量的情况下尽可能的提升设备能效是网络发展的必由之路,本文重点介绍了应用于TD-LTE主设备的几种节能新技术,通过对4G系统架构的分析,从硬件和软件2个方面着重阐述了新技术的原理及节能效果。 相似文献
54.
Sun Minmin Zhang Jianliang Li Kejiang Guo Ke Wang Haiyang Wang Ziming Jiang Chunhe 《Metallurgical and Materials Transactions B》2018,49(5):2611-2621
Metallurgical and Materials Transactions B - The gasification properties of feed coke and tuyere coke were investigated by non-isothermal thermogravimetric method under CO2 atmosphere. The physical... 相似文献
55.
《Intermetallics》2014
Structural modification in a Zr-based metallic glass caused by irradiation with 7 MeV Xe26+ ions was investigated. Needle-like nanocrystalline structures, formed under ion irradiation, consist of Cu10Zr7 phase (primary) and/or minor (NixCu1−x)10Zr7 phase. The formation of needle-like nanocrystals suggested an anisotropic atomic diffusion caused by ion irradiation. 相似文献
56.
Ant colony optimization (ACO) algorithms have been successfully applied in data classification, which aim at discovering a list of classification rules. However, due to the essentially random search in ACO algorithms, the lists of classification rules constructed by ACO-based classification algorithms are not fixed and may be distinctly different even using the same training set. Those differences are generally ignored and some beneficial information cannot be dug from the different data sets, which may lower the predictive accuracy. To overcome this shortcoming, this paper proposes a novel classification rule discovery algorithm based on ACO, named AntMinermbc, in which a new model of multiple rule sets is presented to produce multiple lists of rules. Multiple base classifiers are built in AntMinermbc, and each base classifier is expected to remedy the weakness of other base classifiers, which can improve the predictive accuracy by exploiting the useful information from various base classifiers. A new heuristic function for ACO is also designed in our algorithm, which considers both of the correlation and coverage for the purpose to avoid deceptive high accuracy. The performance of our algorithm is studied experimentally on 19 publicly available data sets and further compared to several state-of-the-art classification approaches. The experimental results show that the predictive accuracy obtained by our algorithm is statistically higher than that of the compared targets. 相似文献
57.
Smoothness, sparsity and self-similarity are the priors widely used in image denoising due to their importance in representing natural images. Motivated by the collaborative roles of higher order singular value decomposition and total variation regularization, a new approach that can simultaneously capture the above priors is proposed in this paper for removing the multiplicative noises. By taking advantages of local adaptiveness, sparsity and self-similarity realized by higher order singular value decomposition, the proposed approach starts with similar-patch-group-wise adaptive denoising on the log-transformed image, followed by the iterative optimization implemented by the total variation constraint which considers the prior of smoothness. Experiments demonstrate the advantages of the proposed approach in removing multiplicative noise and preserving the details near the edges and in the texture area. 相似文献
58.
首先分析了流量经营的13个典型业务场景,提出了流量经营的建设方案,包括流量经营的措施和整体体系架构。然后提出了以GGSN为中心面向网络的智能管道和综合网关面向业务智能运营的远期建设思路。最后,提出了GGSN智能分流和综合网关深度业务处理的近期建设方案和双策略控制接口。 相似文献
59.
Abstract A general formalism of a three-level atom interacting with one-mode or two-mode cavity fields in a Kerr-like medium is presented. Dynamic behaviours of the atomic occupation probabilities and the transfer phenomena are investigated numerically in two typical cases. Our results show that the transfer phenomena may depend on the initial conditions. 相似文献
60.