基于多目标粒子群优化的虚拟网络映射算法

在虚拟网络映射中,多数研究只考虑一个映射目标,不能体现多方的利益。为此,将多目标算法和粒子群算法结合,提出了一种基于多目标粒子群优化（PSO）的虚拟网络映射算法（VNE-MOPSO）。首先,在基本的粒子群算法中引入交叉算子,扩大了种群优化的搜索空间;其次,在多目标优化算法中引入非支配排序、拥挤距离排序,从而加快种群的收敛;最后,以同时最小化成本和节点负载均衡度为虚拟网络映射目标函数,采用多目标粒子群优化算法求解虚拟网络映射问题（VNMP）。实验结果表明,采用该算法求解虚拟网络映射问题,在网络请求接受率、平均成本、平均节点负载均衡度、基础设施提供商的收益等方面具有优势。     

铜互连线内电流拥挤效应的影响

提出了一种新的测试结构(S结构),通过实验、理论推导和有限元分析,研究了铜与TaN扩散阻挡层界面的电流拥挤效应对电迁移致质量输运特性的影响.实验和有限元分析表明,铜互连线内由于电流拥挤效应的存在,在用户温度下沿特定通道输运的局部原子通量显著增大,而焦耳热所产生的温度梯度对原子通量和通量散度增大的影响则相对有限.     

纤维分散性的评价

纤维在水中或其它液体介质中的分散性能是影响纸页质量或其它湿法成型纤维材料质量的主要因素。评价纤维的分散性可以直接检测分析产品,也可以直接观察和比较纤维-介质分散体系中的现象。利用“拥挤因子”可以较好地评价与判断纤维在水中的分散性和絮聚性。本文介绍了拥护因子的定义,影响拥护因子的因素以及拥护因子与纤维分散性的关系。     

大豆分离蛋白-葡聚糖糖基化产物作为乳化剂和活性物质载体的性能分析

研究大豆分离蛋白(soy protein isolate,SPI)-葡聚糖共价接枝物的制备及其乳化性质和作为姜黄素载体的性能。在95℃的"大分子拥挤"体系条件下,2种大分子通过美拉德反应进行共价接枝。根据糖基化产物在SPI等电点附近(p H 4.5)和中性(p H 6.5)条件下的溶解性将其分成2个组分,分别为MC45和MC65,并对其性能表征分析。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳和分子质量测定分析显示,反应后生成大分子质量的接枝物。MC45制备的乳液在酸性环境中的粒度低于MC65,其平均粒径约为10μm,并且受离子浓度和温度的影响较小。与天然蛋白、SPI-葡聚糖混合物及MC45相比,荷载量、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除率分析表明MC65组分具有更好的姜黄素运载性能,MC65组分制备的姜黄素纳米颗粒荷载量为30.21μg/mg,DPPH自由基清除率为18.33%,其粒径最大。     

多目标模糊作业车间调度问题研究

研究了具有模糊加工时间和模糊交货期的多目标作业车间调度问题,首先给出了基于模糊优先规则的编码新方式,染色体的每一位表示在GT算法迭代过程中,对应机器上发生的某次冲突,根据该基因位对应的优先规则消除。然后设计了基于个体密集距离的多目标进化算法,该算法利用密集距离进行外部档案维护和适应度赋值。最后将多目标进化算法应用于模糊作业车间调度问题,以最大化最小一致指标和最小化模糊最大完成时间,并和其他算法比较。计算结果验证了多目标进化算法在模糊调度方面良好的搜索性能。     

Using Holographic Microscopy To Measure the Effect of Confinement on Crowding Agents in Lipid Vesicles

The hydrodynamic effects of macromolecular crowding inside cells are often studied in vitro by using polymers as crowding agents. Confinement of polymers inside cell-sized droplets has been shown to affect the diffusion of small molecules. Here we develop a method, based on digital holographic microscopy, to measure the diffusion of polystyrene microspheres that are confined within lipid vesicles containing a high concentration of solute. We apply the method to three solutes of varying complexity: sucrose, dextran, and PEG, prepared at ∼7 % (w/w). We find that diffusion inside and outside the vesicles is the same when the solute is sucrose or dextran that is prepared below the critical overlap concentration. For poly(ethylene glycol), which is present at a concentration higher than the critical overlap concentration, the diffusion of microspheres inside vesicles is slower, hinting at the potential effects of confinement on crowding agents.     

Molecular diffusion in ternary poly(vinyl alcohol) solutions

The diffusion kinetics of a molecular probe—rhodamine B—in ternary aqueous solutions containing poly(vinyl alcohol), glycerol, and surfactants was investigated using fluorescence correlation spectroscopy and dynamic light scattering. We show that the diffusion characteristics of rhodamine B in such complex systems is determined by a synergistic effect of molecular crowding and intermolecular interactions between chemical species. The presence of glycerol has no noticeable impact on rhodamine B diffusion at low concentration, but significantly slows down the diffusion of rhodamine B above 3.9% (w/v) due to a dominating steric inhibition effect. Furthermore, introducing surfactants (cationic/nonionic/anionic) to the system results in a decreased diffusion coefficient of the molecular probe. In solutions containing nonionic surfactant, this can be explained by an increased crowding effect. For ternary poly(vinyl alcohol) solutions containing cationic or anionic surfactant, surfactant–polymer and surfactant–rhodamine B interactions alongside the crowding effect of the molecules slow down the overall diffusivity of rhodamine B. The results advance our insight of molecular migration in a broad range of industrial complex formulations that incorporate multiple compounds, and highlight the importance of selecting the appropriate additives and surfactants in formulated products.