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71.
在简要介绍多变量模糊系统的模糊穴-穴映射(FCM-I)模型的基础上,提出了一种对多变量模糊系统进行分解的方法。此法的核心在于认为任何复杂系统的动态都是由其隐含的稳定子动态和不稳定于动态聚合而成,而系统特性则主要取决于决定性子动态的性质。并介绍了确定系统决定性子动态和基于其上的多变量模糊系统渐近分析方法。  相似文献   
72.
针对特大功率AT变速器特点,分析其对整车性能的影响,制定了性能比对试验方案,并通过对某型号国外样机与国产样机进行对标分析来验证其是否合理、有效.结果表明,所制定的试验方案能够客观反映样品的性能,对该类型产品的性能评价方法亦具有借鉴意义.  相似文献   
73.
采用改进的主动轮廓模型算法,实现从蝴蝶兰花簇图像中提取单个花朵图像,为自动识别蝴蝶兰的生长状态奠定基础。首先利用改进的骨架算法和轮廓重生算法,生成蝴蝶兰花簇的初始轮廓;然后利用含有形状能量的主动轮廓模型进行轮廓的演化,使其更接近真实的蝴蝶兰花簇边缘,最后根据蝴蝶兰花蕊位置获得相应的蝴蝶兰花朵。实例验证和比对实验结果表明,该模型能够较好的分割和提取蝴蝶兰花簇中单个花朵,并具有较强的抗噪能力。利用该方法,可以较好的提取蝴蝶兰花簇中的单个花朵,与人工提取效果进行比对,正确率达到了91.5%。  相似文献   
74.
通过分析大型农机在农业生产实践中发展的必然性和面临的问题,阐述了大型农机在现代农业生产中的作用和发展建议.  相似文献   
75.
Non-alcoholic fatty liver disease (NAFLD) is characterized by excessive fat deposition in the liver, which is often associated with disrupted iron homeostasis. Betaine has been reported to be hepatoprotective, yet whether and how betaine ameliorates high-fat diet-induced disruption of hepatic lipid and iron homeostasis remains elusive. In this study, mice were fed either standard (CON) or high-fat diet (HFD) for 9 weeks to establish a NAFLD model. Mice raised on HF diet were then assigned randomly to HF and HFB groups, HFB group being supplemented with 1% (w/v) of betaine in the drinking water for 13 weeks. Betaine supplementation significantly alleviated excessive hepatic lipid deposition and restored hepatic iron content. Betaine partly yet significantly reversed HFD-induced dysregulation of lipogenic genes such as PRARγ and CD36, as well as the iron-metabolic genes including FPN and HAMP that encodes hepcidin. Similar mitigation effects of betaine were observed for BMP2 and BMP6, the up-stream regulators of hepcidin expression. Betaine significantly rectified disrupted expression of methyl transfer gene, including BHMT, GNMT and DNMT1. Moreover, HFD-modified CpG methylation on the promoter of PRARγ and HAMP genes was significantly reversed by betaine supplementation. These results indicate that betaine alleviates HFD-induced disruption of hepatic lipid and iron metabolism, which is associated with modification of CpG methylation on promoter of lipogenic and iron-metabolic genes.  相似文献   
76.
The white-backed planthopper (WBPH), Sogatella furcifera, is one of the most important piercing-sucking pests of rice (Oryza sativa) in Asia. Mucin-like salivary protein (SFMLP) is highly expressed in the salivary glands of WBPH, which plays an important role in WBPH feeding. In this study, WBPH injected with dsSFMLP had difficulty in sucking phloem sap from rice plants, which significantly reduced their food intake, weight, and survival. In contrast, the knockdown of the SFMLP gene had only a marginal effect on the survival of WBPH fed an artificial diet. Further studies showed that silencing SFMLP resulted in the short and single-branched salivary sheaths secretion and less formation of salivary flanges in rice. These data suggest that SFMLP is involved in the formation of the salivary sheath and is essential for feeding in WBPH. Overexpression of the SFMLP gene in rice plants promoted the feeding of WBPH, whereas silencing the gene in rice plants significantly decreased WBPH performance. Additionally, it was found that overexpression of SFMLP in rice plants elicited the signalling pathway of SA (salicylic acid) while suppressing JA (jasmonic acid); in contrast, silencing of the SFMLP gene in rice plants showed the opposite results. This study clarified the function of SFMLP in WBPH feeding as well as mediating rice defences.  相似文献   
77.
以失水山梨醇单油酸酯(Span-80)作为乳化剂,偶氮二异丁基脒盐酸盐作为聚合引发剂,以丙烯酸(AA)、丙烯酰胺(AM)、二甲基二烯丙基氯化铵(DADMAC)和特殊单体为反应物,通过反相乳液聚合法合成了一种新型水包油型高分子乳化剂C-5,并考察了这种乳化剂的耐盐耐溶剂性能.  相似文献   
78.
This paper addresses the full‐duplex relaying. Some expressions for outage and average capacity of a two‐hop cooperative system with a full‐duplex relay are derived under an independent but not identically distributed Rayleigh fading environment. Using these expressions, we provide the performance analysis without Monte Carlo simulations. The impact of interference between the relay output and input is investigated. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
79.
常熟华府世家工程是一栋高层建筑,由于在转换梁的布置中有多次梁抬墙的情况,采用整体性好的箱形转换结构。对箱形转换层及其上下若干楼层的受力进行了计算,根据计算结果对箱形转换层进行结构设计。计算结果表明,采用箱形转换层提高了结构的整体性和抗震性能,结构的变形满足规范要求。对箱形转换结构的设计和施工中要注意的问题进行了探讨。  相似文献   
80.
We examined whether sulfated hyaluronan exerts inhibitory effects on enzymatic and biological actions of heparanase, a sole endo-beta-glucuronidase implicated in cancer malignancy and inflammation. Degradation of heparan sulfate by human and mouse heparanase was inhibited by sulfated hyaluronan. In particular, high-sulfated hyaluronan modified with approximately 2.5 sulfate groups per disaccharide unit effectively inhibited the enzymatic activity at a lower concentration than heparin. Human and mouse heparanase bound to immobilized sulfated hyaluronan. Invasion of heparanase-positive colon-26 cells and 4T1 cells under 3D culture conditions was significantly suppressed in the presence of high-sulfated hyaluronan. Heparanase-induced release of CCL2 from colon-26 cells was suppressed in the presence of sulfated hyaluronan via blocking of cell surface binding and subsequent intracellular NF-κB-dependent signaling. The inhibitory effect of sulfated hyaluronan is likely due to competitive binding to the heparanase molecule, which antagonizes the heparanase-substrate interaction. Fragment molecular orbital calculation revealed a strong binding of sulfated hyaluronan tetrasaccharide to the heparanase molecule based on electrostatic interactions, particularly characterized by interactions of (−1)- and (−2)-positioned sulfated sugar residues with basic amino acid residues composing the heparin-binding domain-1 of heparanase. These results propose a relevance for sulfated hyaluronan in the blocking of heparanase-mediated enzymatic and cellular actions.  相似文献   
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