可延迟网络数据传输拥塞优化控制方法

可延迟网络中没有固定端到端的连接,而传统网络大部分采用端到端传输控制协议完成拥塞控制,不适于可延迟网络的拥塞控制.为此,提出一种新型的可延迟网络数据传输拥塞优化控制方法.把确定时间的可延迟网络看作随时间改变的无限网络序列,对时间进行离散化处理,将节点间路径的抵达时间当成路径距离的衡量指标,建立可延迟网络拓扑变化的时间演化图.把可延迟网络的资源分配问题看作非线性优化问题,建立效用最大化模型.针对给出的各条链路尝试概率,获取所有业务流的最佳数据传输速率,达到控制数据传输拥塞的目的.为了改进可延迟网络中拥塞参数的选择,需对数据传输拥塞状态进行训练,完成对拥塞状态参数的优化操作.实验结果表明,所提方法拥塞控制性能优.

基于可延迟调度提升实时数据对象时序一致性服务质量算法

针对保证实时数据对象时序一致性调度算法在软实时数据库系统环境下的应用问题,提出了一种基于概率统计的可延迟优化(SDS-OPT)算法。首先,分析和比较了现有算法在可调度性、服务质量(Qo S)以及工作负载方面的特征与不足,指出优化现有算法的必要性;然后,利用最速下降法提升作业的执行时间筛选基准值,进而增加实时更新事务可调度的作业数量,以确保实时数据对象的时序一致性服务质量(Qo S)最大化;最后,从工作负载和服务质量两个方面对所提算法和现有算法的性能进行对比分析。仿真实验结果表明,相对于已有的针对固定优先级可延迟调度算法(DS-FP)和统计性的非确定性可延迟调度算法(DS-PS),所提算法能够保证实时数据对象的时序一致性,同时降低工作负载,服务质量提升明显。

新型可延迟膨胀类堵漏剂的合成与性能评价

现有的凝胶堵漏剂吸水膨胀速度过快,导致堵漏剂难以进入漏层;部分进入漏层的堵漏剂,因提前膨胀致使填塞层强度低,堵漏效果差。采用丙烯酸(AA)、丙烯酸甲酯(MA)、2-丙烯酰胺-2-甲基丙磺酸衍生物(AMPSA)、N,N’-亚甲基双丙烯酰胺(MBA)为原料合成可延迟膨胀堵漏剂BZYD-1,对其进行表征,评价了其可延迟性能及承压堵漏能力。结果表明:所合成的可延迟膨胀堵漏剂BZYD-1热稳定性好,抗温达150℃;室温时,清水浸泡几乎不发生吸水膨胀,碱性条件下浸泡4 h膨胀率不大于50%;80℃时,碱性条件下吸水膨胀率达到17.8倍,具有显著的延迟膨胀效果,承压能力为4 MPa。该延迟膨胀堵漏剂具有较好的应用前景。

主胰管减压可延迟慢性胰腺炎中胰腺功能的进行性丧失

慢性胰腺炎常伴发胰腺功能进行性损害,1988年作者曾对68例慢性胰腺炎平均随访14个月,证实手术病人的胰腺功能损害得以延缓。这次作者报告143例慢性胰腺炎的前瞻性研究结果。均作ERCP检查、脂餐胰多肽释放和口服葡萄糖耐量试验、胰岛素测定、

过早分娩与延迟分娩的原因

一项动物研究表明,过早地释放催产素可引起早产,而延迟释放此激素可延迟到最佳分娩时间之后分娩。上述研究结果可能导致产生一些预防早产的药物,以便通过在子宫内阻断催产素的作用。早产是新生儿死亡的一个主要原因。

对采后钙渗入法延迟油梨成熟的评价

在澳大利亚三个油梨种植区从80位种植者处采集油梨进行了两个收获季的试验,以研究真空渗入钙对尚未完全后熟的油梨品种哈斯(Haas)和富特(Fuerte)果实延迟成熟的效果(与非处理果实相比较)。处理的效应不一。在默里河谷地,66％果园的哈斯油梨显然延迟成熟,所有处理果实的成熟时间比对照延迟45％。各地富特油梨的反应相似,成熟时间平均延迟30％,60％果园的果实贮藏时间显著延长。北昆士兰和北新南威尔士的哈斯油梨平均延迟成熟的时间最短(约10％),有25％果园的果实显著延迟成熟。成熟哈斯油梨的质量不受钙渗透的影响,富特油梨的质量有所下降。

鹿用增茸素

鹿茸周期性生长、脱落与睾酮分泌水平呈负相关,即睾酮处于低水平时,鹿茸快速生长发育,睾酮处于高水平时,鹿茸快速骨化,停止生长。若在锯头茬茸后人为地控制睾酮分泌,则可延迟鹿茸骨化,降低性欲,既可提高再生茸的产量。

桔树夏季修剪注意三点

一、修剪时间。成年桔树夏季修剪过早,枝芽分辨困难,座果较小,影响当年产量;过迟,干旱到来,供水困难,剪后不利抽梢生长。因此,修剪时间应在第二次生理落果后的7月前后为宜。若当年雨水充沛,灌溉便利,也可延迟到7月底8月初进行。

大豆磷脂可防肝硬化

当今,肝硬化已是肝病中死亡率很高的一种病患,美国学者进行的一项长期研究证明,大豆里的卵磷脂可延迟和防止酒精性肝硬化的发病。这是纽约西奈山医学院里伯氏及其同事们研究的成果,发表于近期《肝脏病》杂志上。 动物试验显示,他们把12只猩猩分成两组,一组的食料中补充大豆卵磷脂,另一组则不加卵磷脂,两组都每天给8听啤酒的量喂饮。

Novel kind of lyot birefringent tunable filters

The retardation of wave plate has the sensitivity to the incident angle.We design a new kind of tunable Lyot filter based on the sensitivity.The method of tuning is rotating the wave plate by the axial direction parallel to the optical axis.It is proved that this kind of tunable Lyot filter has the properties of favorable tenability,wide tunable range.

Guaranteed cost control of networked control systems under limited communication capacity and variable sampling

The problem of guaranteed cost control for the networked control systems(NCSs) with time-varying delays, time-varying sampling intervals and signals quantization was investigated, wherein the physical plant was continuous-time one, and the control input was discrete-time one. By using an input delay approach and a sector bound method, the network induced delays, quantization parameter and sampling intervals were presented in one framework in the case of the state and the control input by quantized in a logarithmic form. A novel Lyapunov function with discontinuity, which took full advantages of the NCS characteristic information, was exploited. In addition, it was shown that Lyapunov function decreased at the jump instants. Furthermore, the Leibniz-Newton formula and free-weighting matrix methods were used to obtain the guaranteed cost controller design conditions which were dependent on the NCS characteristic information. A numerical example was used to illustrate the effectiveness of the proposed methods.

A distributed routing algorithm based-on simplified topology in LEO satellite networks

In this paper, a distributed muting strategy based on simplified topology （DRBST） was proposed for LEO satellite networks. The topology of LEO satellite networks was simplified aiming at minimizing intersatellite links handover number. To optimize the route based on the simplified topology, we considered not only the transmission delay but also the queuing delay and the processing delay, which were analyzed using Markov chain and determined using a novel methodology. The DRBST algorithm was simulated in a LEO satellite networks model built using OPNET. The simulation results demonstrate that the low complexity DRBST algorithm can guarantee end-to-end delay bound. Moreover, the muting protocol cost is much less than traditional algorithms.

Adaptive clustering hierarchy routing for delay tolerant network

Adaptive clustering hierarchy routing(ACHR) establishes a clusters-based hierarchical hybrid routing algorithm with two-hop local visibility for delay tolerant network(DTN).The major contribution of ACHR is the combination of single copy scheme and multi-copy scheme and the combination of hop-by-hop and multi-hop mechanism ACHR,which has the advantages in simplicity,availability and well-expansibility.The result shows that it can take advantage of the random communication opportunities and local network connectivity,and achieves 1.6 times delivery ratio and 60% overhead compared with its counterpart.

Matrix-Geometric Method Based Unified Delay Analysis for Wireless Relay Networks

A lot of work has been focused on desig-ning and analyzing various cooperative diversity pro-tocols for wireless relay networks. To provide a uni-fied queuing analytic framework, we fonmlate an em-bedded Markov chain, which rams out to be a Quasi-Birth-and-Death （QBD） process. Using the Matrix-Ce-ometric method, we can analyze the average delay in a unified way. Theoretical analysis is validated by simu-lation results. We show that the delay performances of Amplify-and-Forward or Decode-and-Forwaxd （AF/ DF） and incremental AF/DF schemes can be analyzed in the unified way. Thus, we can always choose the best cooperative diversity scheme in different scenari-os for delay minimization.

Mean square stability of recurrent neural networks with random delay and Markovian switching

To establish easily proved conditions under which the random delayed recurrent neural network with Markovian switching is mean-square stability,the evolution of the delay was modeled by a continuous-time homogeneous Markov process with a finite number of states.By employing Lyapunov-Krasovskii functionals and conducting stochastic analysis,a linear matrix inequality (LMI) approach was developed to derive the criteria for mean-square stability,which can be readily checked by some standard numerical packages such as the Matlab LMI Toolbox.A numerical example was exploited to show the usefulness of the derived LMI-based stability conditions.

A software reliability growth model for component-based software incorporating debugging delay and imperfect debugging

In view of the problems and the weaknesses of component-based software （ CBS ） reliability modeling and analysis, and a lack of consideration for real debugging circumstance of integration tes- ting, a CBS reliability process analysis model is proposed incorporating debugging time delay, im- perfect debugging and limited debugging resources. CBS integration testing is formulated as a multi- queue muhichannel and finite server queuing model （MMFSQM） to illustrate fault detection process （FDP） and fault correction process （FCP）. A unified FCP is sketched, given debugging delay, the diversities of faults processing and the limitations of debugging resources. Furthermore, the impacts of imperfect debugging on fault detection and correction are explicitly elaborated, and the expres- sions of the cumulative number of fault detected and corrected are illustrated. Finally, the results of numerical experiments verify the effectiveness and rationality of the proposed model. By comparison, the proposed model is superior to the other models. The proposed model is closer to real CBS testing process and facilitates software engineer＇ s quantitatively analyzing, measuring and predicting CBS reliability. K

Low latency systolic multipliers for finite field GF（2m） based on irreducible polynomials

Systolic implementation of multiplication over GF(2m) is usually very efficient in area-time complexity,but its latency is usually very large.Thus,two low latency systolic multipliers over GF(2m) based on general irreducible polynomials and irreducible pentanomials are presented.First,a signal flow graph(SFG) is used to represent the algorithm for multiplication over GF(2m).Then,the two low latency systolic structures for multiplications over GF(2m) based on general irreducible polynomials and pentanomials are presented from the SFG by suitable cut-set retiming,respectively.Analysis indicates that the proposed two low latency designs involve at least one-third less area-delay product when compared with the existing designs,To the authors' knowledge,the time-complexity of the structures is the lowest found in literature for systolic GF(2m) multipliers based on general irreducible polynomials and pentanomials.The proposed low latency designs are regular and modular,and therefore they are suitable for many time critical applications.

Analysis Markov Delay Control Strategy for Smart Home Systems

with the development of science and technology, smart home systems require better, faster to meet the needs of human. In order to achieve this goal, the human-machine-items all need to interact each other with understand, efficient and speedy. Cps could unify combination with the human-machine-items; realize the interaction between the physical nformation and the cyber world. However, information interaction and the control task needs to be completed in a valid time. Therefore, the transform delay control strategy becomes more and more important. This paper analysis Markov delay control strategy for smart home systems, which might help the system decrease the transmission delay.

中国贸易超调:表现、成因与对策

本文将可能影响中国贸易超调的原因归纳为五类,即贸易结构、供应链国际化、经济形势、贸易政策和中国特定因素,每类指标均选取多个变量纳入计量方程中进行回归分析。经验分析结果稳健地表明,"可延迟商品"的出口比重成为中国贸易超调最重要的影响因素;此外,主要贸易伙伴从中国进口比重、主要贸易伙伴的GDP增长率,以及中国库存占GDP比重,对中国贸易超调也产生了较为重要的作用;而中国参与国际垂直专业化生产程度、出口退税因素以及游资因素对超调幅度的影响未能获得实际数据的支持。未来中国对外贸易克服超调问题,实现健康稳定发展的出路在于,一方面遵循比较优势,承接国际外包,在国际生产链条中扮演好自己的角色,另一方面,积极扩展贸易方向、有选择地接受国际先进生产方式,重视服务贸易发展,加强同贸易伙伴的协调对话,以此来减轻贸易超调的幅度。