基于DiffServ的星上交换设计与仿真

星上交换的设计在满足对综合业务QoS支持的同时,还需要考虑到星上实现复杂度和系统资源的限制.为此,基于DiffServ的思想,将(m,k)模型应用于地面业务到卫星业务的QoS映射,并通过双漏桶模型在业务增长时对星上数据进行有选择的控制,从而建立了一个实现复杂度低且可以有效保证综合业务QoS的星上交换框架.系统建模仿真结果表明,该设计方案在节省星上缓存资源的同时提高了系统性能,对业务的突发具有较好的平滑性.     

无k+1次幂因子数的两个渐近式

引进了两个新的可乘函数U(n)和V(n),利用解析方法研究了∑n∈An≤xU(n)及∑n∈An≤xV(n)的均值分布性质,给出了两个较强的渐近公式,其中A表示所有无k+1次幂因子数组成的集合。所得结果表明这两个可乘函数具有较好的渐近分布性质。     

具有多重延误休假的k out of n(G)冷备可修系统

研究了修理工具有多重延误休假的新型 k out of n(G)冷储备可修系统.假定部件寿命、修理工延误休假时间服从指数分布,部件修理时间、修理工休假时间服从一般分布.利用补充变量法和拉普拉斯变换工具,讨论了此系统的首次故障前平均时间、可用度及(0,t]时间内的平均故障次数等可靠性指标.结果表明,文中讨论的模型比以往的模...     

LL-37/hCAP-18基因克隆及其真核表达载体的构建

LL-37 hCAP-18是一种重要的多功能免疫分子.为探讨hCAP-18在基因治疗中的可行性,应用RT-PCR技术从人白血病细胞系J6-1细胞总RNA中成功扩增出560bp的hCAP-18基因编码区cDNA序列,构建了hCAP-18重组表达质粒phCAP-18.采用脂质体法将质粒phCAP-18瞬时转染COS-7细胞,Westernblot证实,hCAP-18能在COS-7细胞中表达.     

人源抗菌肽LL-37在烟草中的表达

为探讨用植物生物反应器生产LL-37的可行性,利用DNA重组技术将LL-37与植物病程相关蛋白信号肽基因融合,经测序证实序列和阅读框正确后,连接到质粒pBin438上,构建含LL-37 cDNA植物分泌型表达载体pBin/LL-37.通过根癌土壤杆菌(Agrobacterium tumefacience)介叶盘法转化烟草(Nicotiana tobacum.NC-89).用PCR和Western blot对转化植株进行分子鉴定.80%转基因植株表达重组LL-37多肽.T0代转基因烟草的蛋白粗提物有抑制Staphylococcus aureus和Escherichia coli生长的活性.LL-37基因在转基因烟草中成功表达,提示用植物表达系统生产活性LL-37蛋白是可行的.     

关于Smarandache LCM函数与k次补数的一个混合均值

对任意的非负整数n,著名的Smarandache LCM函数SL(n)定义为最小的正整数k,使得n|[1,2,…,k],其中n|[1,2,…,k]表示1,2,…,k的最小公倍数。设k≥2为给定的整数,bk(n)定义为最小的正整数使得bk(n)·n为完全k次幂,则称bk(n)为n的k次补数。本文主要利用初等及解析方法,研究复合函数SL(bk(n))与n的最大素因子函数P(n)的均方差,得到了一个较强的渐近公式。     

Sea surface temperature records of core ZY2 from the central mud area in the South Yellow Sea during last 6200 years and related effect of the Yellow Sea Warm Current

Sea surface temperature (SST) records in the South Yellow Sea during the last 6200 years are reconstructed by the unsaturation index of long-chain alkenones (K 37 U ’) in sediment core ZY2 from the central mud area.The SST records varied between 14.1 and 16.5°C (15.6°C on average),with 3 phases:(1) A high SST phase at 6.2-5.9 cal ka BP;(2) A low and intensely fluctuating SST phase at 5.9-2.3 cal ka BP;and (3) A high and stable SST phase since 2.3 cal ka BP.Variation of the SST records is similar to intensity of the Kuroshio Current (KC),and corresponds well in time to global cold climate events.However,the amplitude of the SST response to cooling events was significantly different in different phases.The SST response to global cooling event was weak while the KC was strong;and the SST response was strong while the KC was weak.The difference in amplitude of the SST response is possibly caused by the modulation effect of the Yellow Sea Warm Current which acts as a shelf branch of the KC and a compensating current induced by the East Asia winter monsoon.The warm waters brought by the Yellow Sea Warm Current cushion the SST decrease induced by climate cooling,and both the Kuroshio and East Asian winter monsoon play important roles in the modulation mechanism.The SST records display a periodicity of 1482 years.The same period was found in the KC records,indicating that variation of the SST records in the central South Yellow Sea is strongly affected by KC intensity.The same period was also found in Greenland ice cores and North Atlantic and Arabian Sea sediment cores,showing a regional response of marine environmental variability in the East China Seas to that in the global oceans.     

幂级数∑mk 部分和的组合表达式

本文给出了级数∑m k 部分和的组合表达式：m ＝1∞∑m k ＝f1k n ＋1()1＋f 2 k m ＝1 k ＋()1＋f n ＋2 k ＋3 k ()1＋…f n ＋3 k ＋k k ()1, n ＋k k ＋并讨论了由这些系数构成的三角形的对称性以及此三角形内相邻行间元素的递归关系。     

A routing algorithm for industrial wireless network based on ISA100.11a

ISA100.11 a industrial wireless network standard is based on a deterministic scheduling mechanism.For the timeslot delay caused by deterministic scheduling,a routing algorithm is presented for industrial environments.According to timeslot,superframe,links,channel and data retransmission of deterministic scheduling mechanisms that affect the design of the routing algorithm,the algorithm selects the link quality,timeslot delay and retransmission delay as the routing criteria and finds the optimum communication path by k shortest paths algorithm.Theoretical analysis and experimental verification show that the optimal paths selected by the algorithm not only have high link quality and low retransmission delay,but also meet the requirements of the deterministic scheduling.The algorithm can effectively solve the problem of packet loss and transmission delay during data transmission,and provide a valuable solution for efficient data transmission based on determinacy.     

一种基于近邻搜索的快速k-近邻分类算法

针对传统快速k 近邻分类算法的缺陷 ,提出了一种基于近邻搜索的快速k 近邻分类算法———超球搜索法。该方法通过对特征空间的预组织 ,使分类在以待分样本为中心的超球内进行 ,有效地缩小了搜索范围。实验结果表明 ,在相同识别率和k值的情况下 ,超球搜索法的识别速度优于基本k 近邻法和传统快速k 近邻算法———及时终止法 ,而且不存在对训练样本搜索顺序敏感性的问题