A resilient buffer allocation scheme in active queue management: a stochastic cooperative game theoretic approach

During the last decade, a plentiful number of active queue management schemes have been proposed, but their main objectives are simply allocating the buffer resource to all flows evenly, or protecting responsive flows from being degraded by unresponsive flows. However, the sending rates of the responsive flows can be determined diversely, and not all unresponsive flows have aggressively high sending rates. Furthermore, it is rational to reserve a portion of the buffer resource for certain privileged traffic. Grounded by these evidences, in this paper, we present a resilient active queue management algorithm, named Prior‐Core‐based Buffer Allocation considering diverse congestion control algorithms, fair‐unresponsive flows, and some privileged traffic. Our approach is based on stochastic cooperative game theory, where the payoffs yielded by cooperation are described by random variables, and the core is defined only over the distribution of these random payoffs; the core in this situation is called the prior‐core. As a result, it is shown that our buffer allocation, yielded by the prior‐core, achieves completely fair allocation for those flows whose requirement does not exceed the fair‐share regardless of the responsiveness, whereas aggressive flows are restricted according to availability of the buffer; all these are verified through ns‐2 simulation experiments. Copyright © 2014 John Wiley & Sons, Ltd.     

媒介融合是一项从核心价值观到技术形态的系统工程

媒介融合融什么?这不仅是一个传媒业界的实践问题,也是传播学学界亟待阐释的学理问题。媒介融合需要顶层设计;媒介融合是一项从核心价值观到媒介技术形态的网络化系统工程。媒介融合当以社会主义核心价值观观照传媒意识形态和技术形态,以媒介的互动性激活受众的主体性,为用户提供优质的信息增值服务。     

茅台镇酱香型白酒酿造环境中真菌菌群多样性分析

采用高通量测序技术结合数理统计软件分析方法，系统研究茅台镇酱香型白酒不同酿造轮次生产环境中的真菌菌群结构及特征。7 个轮次中共检测到4 个真菌门、212 个真菌属。根据各菌门、属的相对丰度，子囊菌门（Ascomycota）和担子菌门（Basidiomycota）是茅台镇酱香型白酒酿造环节中各酿造轮次的优势菌门，节担菌属（Wallemia）、复膜孢酵母属（Saccharomycopsis）为各轮次绝对优势真菌属。不同轮次环境样品中真菌组成结构的相似度较高，但其各轮次标志性真菌属存在差异。7 个酿造轮次共有相同真菌属56 个，在各轮次占主导地位，特征性真菌属在各轮次当中相对丰度和占比较小但种类丰富。Ascomycota最强节点为德巴利酵母属（Debaryomyces），Basidiomycota最强节点为红酵母属（Rhodotorula）。本研究揭示了茅台镇酱香型白酒不同酿造轮次环境中真菌菌群结构及其特征，为深入研究酱香型白酒酿造机理以及对酿造环境中微生物结构的解析提供了参考依据。     

基于竹筋-钢筋骨架的人工假顶首层充填厚度研究及现场应用

采用简支梁理论、ANSYS软件数值模拟与现场试验相结合的方法,对竹筋-钢筋骨架人工假顶进行了可行性、受力行为、破坏方式与合理设计参数研究。结果表明,竹筋-钢筋骨架人工假顶结构可有效保护上部充填体,最优充填厚度为4.75 m; 采用竹筋-钢筋配筋方式可兼顾采场稳定性与经济效益,减少支护成本约15%。     

铸绩效理论指导壳型铸造气缸体组芯胎具的优化设计

介绍了小型干式缸套气缸体复杂薄壁类铸铁件壳型铸造生产中,应用传统观念手工组芯方法存在的诸多不足。阐述了采用绩效理论指导小型气缸体壳型铸造的气缸体砂型铸造中组芯胎具的工艺结构、砂芯锁紧工艺结构和方法等方面的优化设计,以及使其能在小型干式缸套气缸体铸铁件壳型铸造过程中获得良好的工艺效果。     

Preparation of NaYF4:Yb3+,Tm3+@NaGdF4:Ce3+,Eu3+ double-jacket microtubes for dual-mode fluorescent anti-counterfeiting

Novel hydrophilic NaYF₄:Yb³⁺,Tm³⁺@NaGdF₄:Ce³⁺,Eu³⁺ double-jacket microtubes (DJMTs) with upconversion/ downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF₄:Ce³⁺, Eu³⁺ shell onto the NaYF₄:Yb³⁺,Tm³⁺ microtube via poly(acrylic acid) (PAA) mediated hydrothermal method. It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF₄:Ce³⁺,Eu³⁺ shell onto the surface of NaYF₄:Yb³⁺,Tm³⁺ parent microtubes. The growth of NaGdF₄:Ce³⁺,Eu³⁺ shell experienced a crystal phase transition from β-NaGdF₄ and β-NaYF₄ mixture to β-NaYF₄@NaGdF₄ composite crystal, and morphology evolution from mixture of β-NaGdF₄:Ce³⁺,Eu³⁺ nanorods and β-NaYF₄:Yb³⁺,Tm³⁺ microtubes to NaYF₄:Yb³⁺,Tm³⁺@NaGdF₄: Ce³⁺,Eu³⁺ DJMTs. The formation mechanism of DJMTs was the dissolution−renucleation of β-NaGdF₄:Ce³⁺,Eu³⁺ nanorods and the growth of β-NaGdF₄:Ce³⁺,Eu³⁺ shell via the classical Ostwald ripening mechanism. The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence, which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.     

去学沥青混凝土心墙坝高基座体型研究

依托坝高173.2m的四川去学沥青混凝土心墙堆石坝,介绍了一种基于高基座的沥青混凝土心墙坝型,通过对该坝进行二维有限元计算,分析了混凝土高基座的应力分布规律。在此基础上,对原设计方案进行了优化。结果表明,采用优化的基座体型后,混凝土基座的最大压、拉应力均大幅降低,最大拉应力降低近70%。去学沥青混凝土心墙堆石坝的成功建设,对今后类似工程设计具有重要参考价值。     

多种抽芯机构的汽车内门把手座注塑模设计

针对汽车内门把手座使用性能要求,选用30%玻璃纤维增强尼龙6作为成型原料。注塑模具的浇注系统采用热流道转冷流道及潜伏式浇口进料方式,降低了人工剪浇口成本。根据塑件含有的侧孔、侧向凹槽、卡扣等细节特征,设计了相应的斜导柱滑块二级抽芯机构和特殊的斜向液压内侧二级抽芯机构,并对侧抽芯机构的工作过程进行详细分析。实践证明,设计的模具结构合理,工作稳定,对同类注塑模具设计有一定的参考价值。     

微型离心泵泵叶三层式滑块机构三板模具设计

针对微型离心泵泵叶塑件成型模具设计困难的问题，设计了一种改进型三板点浇口模以用于该泵叶塑件的成型。塑件的浇注成型应用3个点浇口来进行平衡注塑，以控制塑件成型变形。模腔布局为1模1腔。针对塑件叶槽区域脱模困难问题，设计了一种3层3次复合抽芯脱模用于难脱模叶槽部位特征的脱模，机构中，将叶槽部位特征的成型块分割成2层成型件后，机构的第一次抽芯动作由弹簧驱动上层滑块实施上层成型块的抽芯；机构的第二次抽芯由斜导柱驱动实施下层成型块的抽芯；最后，由弯销驱动基座滑块带动2个侧抽芯滑块向外抽芯，以让出塑件完全顶出脱模的运动空间。第二次抽芯、第三次抽芯的驱动动力分别由模架模板的第三次开模、第四次开模打开来进行驱动。塑件的最终脱模由油缸驱动顶针板及顶杆顶出而实现塑件的完全脱模。基于塑件、流道脱模及抽芯机构的动作需要，将典型三板点浇口模架改进为四板4次开模点浇口，从而能使塑件、流道废料及驱动滑块机构分次按序来实施抽芯脱模。模具脱模机构动作设置合理，机构结构设计巧妙，模具整体工作可靠，有较好的设计参考价值。