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31.
刁玉平  廖铭  刁永平 《电信科学》2012,28(3):99-104
本文的自治互联网技术结合互联网现实,通过现有域名体系构造出自主自治的可扩展域名体系和层次结构,并提供自治网络系统内/间的域名解释机制,甚至可以单边行动的方式实现互联网自治的过渡和改造。  相似文献   
32.
The objective of the present study was to elucidate the physicochemical changes and protein oxidation of porcine longissimus muscle as influenced by different thawing methods. Five kinds of thawing methods, comprising of refrigerator thawing (RT, 4 °C), ambient temperature thawing (AT, 20 °C), water immersion thawing (WT, 14 °C), lotic water thawing (LT, 9 °C), and microwave thawing (MT), were used. There were significant effects on the porcine meat quality due to different thawing methods. RT had the least quality loss and the physicochemical characteristics of pork were closer to fresh muscle than the other thawing methods. MT significantly increased thawing loss, cooking loss, cutting force, carbonyl content, and TBARS (thiobarbituric acid-reactive substances) value, but decreased a* value and Ca-, K-ATPase activities (P < 0.05). Microstructural changes in experimental muscle showed that MT induced visibly larger gap between muscle fibers and tore more muscle fiber bundles compared to the other thawing methods. The reduction of Ca- and K-ATPase activities (P < 0.05) of myofibrillar protein was consistent with the increases in carbonyl content and TBARS value (P < 0.05). The results demonstrated all the thawing methods could cause porcine lipid and protein oxidation. Gel electrophoresis patterns of porcine muscle displayed that different thawing methods did not induce obvious protein aggregates and fragments.  相似文献   
33.

Recently, deep learning, especially convolutional neural networks, has achieved the remarkable results in natural image classification and segmentation. At the same time, in the field of medical image segmentation, researchers use deep learning techniques for tasks such as tumor segmentation, cell segmentation, and organ segmentation. Automatic tumor segmentation plays an important role in radiotherapy and clinical practice and is the basis for the implementation of follow-up treatment programs. This paper reviews the tumor segmentation methods based on deep learning in recent years. We first introduce the common medical image types and the evaluation criteria of segmentation results in tumor segmentation. Then, we review the tumor segmentation methods based on deep learning from technique view and tumor view, respectively. The technique view reviews the researches from the architecture of the deep learning and the tumor view reviews from the type of tumors.

  相似文献   
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35.
Journal of Inorganic and Organometallic Polymers and Materials - Due to their excellent properties, polymides (PIs) result promising as high-performance materials in different technological fields....  相似文献   
36.
Thermal extraction yields were obtained for 13 coals in supercritical ethanol at 250°C. The direct and indirect relationships between extraction yield and coal properties were determined using correlation and path analyses. Both nitrogen content and hydrogen content have significant and positive correlations with thermal extraction yield. However, moisture content, sulfur content, and oxygen content exhibited negative correlations with extraction yield. Path analysis demonstrated that nitrogen and carbon contents had significant direct and indirect influences on extraction yield, respectively. Nitrogen content is the preferential factor for a high extraction yield, followed by carbon and hydrogen contents.  相似文献   
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38.
Simulating regeneration tests of Potassium-Based sorbents that supported by Suzhou River Channel Sediment were carried out in order to obtain parameters of regeneration reaction. Potassium-based sediment sorbents have a better morphology with the surface area of 156.73 m2·g?1, the pore volume of 357.5×10?3 cm3·g?1 and the distribution of pore diameters about 2–20 nm. As a comparison, those of hexagonal potassium-based sorbents are only 2.83 m2g?1, 7.45×10?3 cm3g?1 and 1.72–5.4 nm, respectively. TGA analysis shows that the optimum final temperature of regeneration is 200 and the optimum loading is about 40%, with the best heating rate of 10 °C·min?1. By the modified Coats-Redfern integral method, the activation energy of 40% KHCO3 sorbents is 102.43 kJ·mol?1. The results obtained can be used as basic data for designing and operating CO2 capture process.  相似文献   
39.
电子行业的快速发展对二层型挠性覆铜板的性能提出了更高的要求,针对以聚酰亚胺薄膜为基底材料的二层型挠性覆铜板,分别从改善粘结性能、介电性能和耐热性能3个方面综述了二层型挠性覆铜板的研究进展,并展望了二层型挠性覆铜板的研究方向。  相似文献   
40.
Hemicelluloses were successively extracted from sweet sorghum by hot water, dioxane, DMSO, and different concentrations of NaOH between 0.5% and 6.0%. The yields of the seven fractions together accounted for 88.6% of the original hemicelluloses. The obtained hemicellulosic subfractions were comprehensively investigated by both destructive methods such as alkaline nitrobenzene oxidation and acid hydrolysis and nondestructive techniques such as gel permeation chromatography, Fourier‐transform infrared, 13C‐nuclear magnetic resonance, and 2D‐heteronuclear singular quantum correlation. Sugar composition studies showed that the water‐soluble polysaccharides consisted mainly of glucose, while xylose, arabinose, and glucuronic acid were the major sugars in other hemicellulosic fractions. It was found that the hemicelluloses from sweet sorghum were l‐ arabino‐(4‐O‐methyl‐d‐ glucurono)‐xylans. Comparison with the hemicellulosic fractions dissolved by the alkali treatment, the hemicellulosic fraction extracted by DMSO had lower molecular weight. In addition, it was also found that the hemicelluloses prepared by dioxane and DMSO were more branched since that they had higher nonxylose/xylose ratios than those extracted by the alkali treatment, which were more linear and contained higher amounts xylose. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42790.  相似文献   
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