微分进化算法整数编码策略实现研究

微分进化算法（DE）是模仿生物进化“优胜劣汰、适者生存”的一种随机优化算法,具有简单、快速、鲁棒性好等特点,已经得到广泛应用.通过运用微分进化算法的整数编码方法,在整数空间中求解,并在实数空间中计算解的适应度.使用测试函数对程序进行测试,证明了整数编码解对空间个体中寻优的快速性、准确性.     

基于本体的特征模型演化的一致性验证

针对特征模型的演化导致特征间的冲突问题, 从特征模型的演化方面进行研究, 提出了一种基于本体的特征模型演化的一致性验证方法。首先采用本体理论方法对特征模型的演化进行分析和建模, 建立本体的特征模型元模型; 其次基于上述元模型, 为网上购物系统实例建立相应的网上购物的领域特征模型, 根据需求裁剪出产品特征模型; 然后在Eclipse集成开发环境下, 通过Jena推理机加载规则和产品特征模型进行一致性验证, 当检测到冲突时, 采用演化策略来消除冲突; 最后通过实例研究说明了该方法的有效性。     

Thermal Explosions in the Early Evolution of the Earth

Exothermic regimes in the Earth's interior at an early stage of evolution are considered. Conditions are found that lead to selfaccelerating development of gravitational differentiation—separation of the heavier material forming the Earth's core from silicates in extended and heated local areas.     

如何实现SAP ERP财务报表的灵活定制

如何使得一个不具备ABAP编程语言基础的财务用户能在SAP系统中快速有效地配置财务报表,并灵活定义输出格式,是许多实施SAP ERP系统的公司都会遇到的问题。本文介绍的财务模块报表定制功能旨在SAP ERP中构建一个可视化图形界面,在这个界面中定义报表、报表版本,以及每个版本的输出布局、报表行、报表列、报表单元格的取数逻辑等要素,使得用户在不使用编程工具的前提下实现报表的灵活定制。     

A modified consensus approach to mutagenesis inverts the cofactor specificity of Bacillus stearothermophilus lactate dehydrogenase

Lactate dehydrogenase from Bacillus stearothermophilus is specific for NAD+. There have been several attempts to alter the cofactor specificity of this enzyme, but these have yielded enzymes with relatively low activities that still largely prefer NAD+. A modified consensus approach was used to create a library of phylogenetically preferred amino acids situated near the cofactor binding site, and variants were screened for their ability to utilize NMN+. A triple mutant (Mut31) was discovered that proved to be more catalytically efficient than wild-type. Mut31 was also better at utilizing NAD+ than the wild-type enzyme and was weakly active with NADP+ and NMN+. An analysis of single amino acid substitutions suggested that all three mutations worked in a concerted fashion to yield robust cofactor utilization. When two previously identified amino acid substitutions were introduced into the Mut31 background, the resultant quintuply substituted enzyme not only utilized NADP+ far better than the wild-type enzyme, it actually inverted its preference for NAD+ and NADP+.     

Oxygen and chlorine evolution on RuO2 + TiO2 + CeO2 + Nb2O5 mixed oxide electrodes

A systematic investigation was conducted on the mechanism and electrocatalytic properties of O₂ and Cl₂ evolution on mixed oxide electrodes of nominal composition: Ti/[Ru_(0.3)Ti_(0.6)Ce_(0.1−x)]O₂[Nb₂O₅]_(x) (0 ≤ x ≤ 0.1). For the oxygen evolution, a 30 mV Tafel slope is obtained in the presence of CeO₂, while in its absence a 40 mV coefficient is observed. The intrinsic electrocatalytic activity is mainly due to electronic factors, as result of the synergism between Ru and Ce oxides. For chlorine evolution, the Tafel slope (30 mV) is independent on oxide composition. The best global electrocatalytic activity for ClER was observed in the absence of Nb₂O₅ additive. Variation of the voltammetric charge throughout the experiments confirms high CeO₂ content compositions are fragile, due mainly to the porosity caused by CeO₂ presence. On the other hand, Nb₂O₅ addition decreases considerably this instability.     

基于新模糊准则与 DE算法的红外人体图像分割 *

人体目标的抽取是红外人体图像处理的基础 ,为了有效获取红外图像中的人体目标 ,提出了一种新的图像阈值化方法。首先在对模糊熵方法本质分析的基础上 ,通过参数变换定义了一种新的最小化模糊准则 ,然后将差分演化 ( differential evolution, DE)算法与新模糊准则相结合用于快速、有效地获取最佳阈值 ,最后在真实红外人体图像上与其他方法进行了对比实验。实验结果表明 ,所提出的方法不仅能得到理想的分割结果 ,而且 CPU耗时也较少 ,满足实时性处理要求。     

基于本体的可信软件演化框架模型*

为系统化地考虑开放环境对软件可信性的影响和驱动作用,提出了一种基于本体空间并支持动态演化的框架模型。该模型采用本体空间的方法解决用户、系统和环境三者之间交互的语义问题,在此基础上,通过预定义的规则对软件行为的可信性和自主调整的必要性进行评估,依据评估结果从微观层次的规约制导和宏观层次的人机协同在软件生命周期内对其调整、配置与修正。应用实例及测试结果验证了该框架模型的有效性与可行性。     

Microscopic characterization of semi-solid aluminium alloys

The microstructural evolution and element distribution of the Al-4Cu-Mg alloy during semi-solid compression were investigated,and the precipitate behavior and dislocation morphology were discussed.The experimental results show that the microstructure,the number of CuAl2(θ phase) precipitates,and the dislocation density of the Al-4Cu-Mg alloy depend apparently on the process parameters.More segregation of Cu at the grain boundary happens with an increase of deformation temperature and a decrease of strain ra...     

数据同化框架下红外与可见光图像的可控融合

针对现有图像融合方法的规则不易根据融合图像的后续使用要求进行自适应调整,并且各种方法的优点不易综合的问题,提出一种数据同化框架下的基于粒子群优化(PSD)和差分进化(DE)算法的融合方法。该方法把比率低通金字塔变换作为数据同化系统的模型算子,把非下采样的Contourlet变换(NSCT,nonsubsampled contourlet transform)作为观测算子,根据后续处理对图像各个属性指标值的依赖程度构造目标函数,再利用PSD和DE的混合算法来优化目标函数从而获取合适的影像。两组实验从视觉效果和定量指标两方面验证了方法的有效性。