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基于退火遗传算法的通信网络次级链路吞吐量优化
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作者 张剑豪 李志林 谢庆腾 《电信快报》 2024年第7期34-37,共4页
为了提升通信网络服务质量与性能,降低通信网络丢包量。为此,文章提出基于退火遗传算法的通信网络次级链路吞吐量优化方法,分析通信网络组成结构,以吞吐量最大和网络时延最短为目标建立目标函数,并对次级链路带宽和负载进行约束,建立次... 为了提升通信网络服务质量与性能,降低通信网络丢包量。为此,文章提出基于退火遗传算法的通信网络次级链路吞吐量优化方法,分析通信网络组成结构,以吞吐量最大和网络时延最短为目标建立目标函数,并对次级链路带宽和负载进行约束,建立次级链路吞吐量优化模型,采用退火遗传算法对模型求解,得到最优吞吐量优化策略,实现通信网络次级链路吞吐量优化。经实验证明,设计方法应用下吞吐量提高,丢包量降低,具有良好的优化效果。 展开更多
关键词 退火遗传算法 通信网络 次级链 吞吐量 时延 负载
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几种硅橡胶次级链结构辐射稳定性的理论研究 被引量:3
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作者 宋宏涛 黄玮 +2 位作者 吴文昊 傅依备 张红平 《计算机与应用化学》 CAS 2015年第1期39-42,共4页
采用密度泛函理论的B3LYP方法,以硅橡胶泡沫材料单体二甲基硅氧烷和甲基乙烯基硅氧烷为基础,研究了这两种单体和由其构成的四种次级链结构的相关能量、前沿轨道、振动分析等相关信息。结果显示,前沿轨道显示链结构的敏感点应在含Si-Si... 采用密度泛函理论的B3LYP方法,以硅橡胶泡沫材料单体二甲基硅氧烷和甲基乙烯基硅氧烷为基础,研究了这两种单体和由其构成的四种次级链结构的相关能量、前沿轨道、振动分析等相关信息。结果显示,前沿轨道显示链结构的敏感点应在含Si-Si键的链端和乙烯基部分,分子链结构中的原子排布更易形成共轭或等效于共轭的离域结构时,在遭受辐照等能量注入的情况下可以将能量及时转移而一定程度上避免了链结构的断裂;在遭受外界能量注入时,裂解的部位发生在共轭链段间隙处和前沿轨道所显示的敏感点的可能性比较大。此外,也可以看到甲基乙烯基硅氧烷的引入在一定程度上可以增加材料的化学稳定性却并非一定会对材料的耐辐照稳定性起到增强作用,这应与单体的比例以及乙烯基片段在齿形波动的长链结构中所处的位置有着密切关系。 展开更多
关键词 硅橡胶泡沫 次级链 辐照稳定性 密度泛函
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Nitrogen Sources Affect Streptolydigin Production and Related Secondary Metabolites Distribution of Streptomyces lydicus AS 4.2501 被引量:2
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作者 李良智 乔斌 元英进 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期403-410,共8页
The effects of nitrogen sources on streptolydigin production and distribution of secondary metabolites were investigated for flask cultured S.lydicus AS 4.2501.When peptone,asparamide,and glutamic acid were ex- amined... The effects of nitrogen sources on streptolydigin production and distribution of secondary metabolites were investigated for flask cultured S.lydicus AS 4.2501.When peptone,asparamide,and glutamic acid were ex- amined as the nitrogen source,respectively,liquid chromatography-mass spectrometry(LC-MS)and photodiode array(PDA)analyses revealed the formation of two analogues of streptolydigin in the fermentation broth.When soybean meal was used as the source of nitrogen,three analogues of streptolydigin were detected.The use of am- monium sulfate as a source of nitrogen resulted in a lower pH value of the fermentation system,thus inhibiting streptolydigin biosynthesis and changing the metabolic profiling.Among the nitrogen sources that were made use of,glutamic acid was most favorable to the formation of streptolydigin.Simultaneously,this study also showed that the changing nitrogen sources resulted in altering the production and relative ratios of streptolydigin and its analogues. 展开更多
关键词 Streptomyces lydicus nitrogensource ANALOGUE secondary metabolite streptolydigin
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Assembly and features of secondary metabolite biosynthetic gene clusters in Streptomyces ansochromogenes 被引量:2
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作者 ZHONG XingYu TIAN YuQing +1 位作者 NIU GuoQing TAN HuaRong 《Science China(Life Sciences)》 SCIE CAS 2013年第7期609-618,共10页
A draft genome sequence of Streptomyces ansochromogenes 7100 was generated using 454 sequencing technology. In combination with local BLAST searches and gap filling techniques, a comprehensive antiSMASH-based method w... A draft genome sequence of Streptomyces ansochromogenes 7100 was generated using 454 sequencing technology. In combination with local BLAST searches and gap filling techniques, a comprehensive antiSMASH-based method was adopted to assemble the secondary metabolite biosynthetic gene clusters in the draft genome of S. ansochromogenes. A total of at least 35 putative gene clusters were identified and assembled. Transcriptional analysis showed that 20 of the 35 gene clusters were expressed in either or all of the three different media tested, whereas the other 15 gene clusters were silent in all three different media. This study provides a comprehensive method to identify and assemble secondary metabolite biosynthetic gene clusters in draft genomes of Streptomyces, and will significantly promote functional studies of these secondary metabolite biosynthetic gene clusters. 展开更多
关键词 secondary metabolite gene cluster ASSEMBLE FEATURES draft genome
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