Method of Estimating the State of Complex Technical Objects in Order to Synthesize High-Speed Predicting Systems

An original two-stage method for forming an operational estimate of the state of complex Markovian objects is given which can be used as a basis for synthesizing high-speed predicting systems. The method makes it possible to specify a priori the accuracy of estimating the stochastic characteristics which describe the state of a technical object.     

物流企业竞争关系演变的复杂网络分析

首先根据东莞市2006～2009年物流企业数据,构建了物流企业布尔竞争关系网络模型和加权竞争关系网络模型。然后,用各种静态几何量分析了各年度网络模型的结构属性,并探讨了网络演化的动力机制和经济学背景。通过分析发现,各年度网络的节点度服从幂律尾部分布,直角坐标系下累计节点入度权近似于直线分布,节点出度权服从无标度分布。网络具有小世界特性,并且具有增长性和偏好性。     

Boosting Oxygen Evolution Reaction by Creating Both Metal Ion and Lattice-Oxygen Active Sites in a Complex Oxide

Developing efficient and low-cost electrocatalysts for the oxygen evolution reaction (OER) is of paramount importance to many chemical and energy transformation technologies. The diversity and flexibility of metal oxides offer numerous degrees of freedom for enhancing catalytic activity by tailoring their physicochemical properties, but the active site of current metal oxides for OER is still limited to either metal ions or lattice oxygen. Here, a new complex oxide with unique hexagonal structure consisting of one honeycomb-like network, Ba₄Sr₄(Co_0.8Fe_0.2)₄O₁₅ (hex-BSCF), is reported, demonstrating ultrahigh OER activity because both the tetrahedral Co ions and the octahedral oxygen ions on the surface are active, as confirmed by combined X-ray absorption spectroscopy analysis and theoretical calculations. The bulk hex-BSCF material synthesized by the facile and scalable sol–gel method achieves 10 mA cm⁻² at a low overpotential of only 340 mV (and small Tafel slope of 47 mV dec⁻¹) in 0.1 m KOH, surpassing most metal oxides ever reported for OER, while maintaining excellent durability. This study opens up a new avenue to dramatically enhancing catalytic activity of metal oxides for other applications through rational design of structures with multiple active sites.     

Counterintuitive properties of the fixation time in network-structured populations

Evolutionary dynamics on graphs can lead to many interesting and counterintuitive findings. We study the Moran process, a discrete time birth–death process, that describes the invasion of a mutant type into a population of wild-type individuals. Remarkably, the fixation probability of a single mutant is the same on all regular networks. But non-regular networks can increase or decrease the fixation probability. While the time until fixation formally depends on the same transition probabilities as the fixation probabilities, there is no obvious relation between them. For example, an amplifier of selection, which increases the fixation probability and thus decreases the number of mutations needed until one of them is successful, can at the same time slow down the process of fixation. Based on small networks, we show analytically that (i) the time to fixation can decrease when links are removed from the network and (ii) the node providing the best starting conditions in terms of the shortest fixation time depends on the fitness of the mutant. Our results are obtained analytically on small networks, but numerical simulations show that they are qualitatively valid even in much larger populations.     

城市复杂环境中大型景观岩石控制爆破拆除

介绍了某复杂环境下大型景观岩石的控爆拆除方案、爆破参数以及安全防护措施,并进行了爆破效果的分析,以期作为今后同类工程的借鉴.     

渗透结晶型防水材料不稳定络合物的分光光度法测定

水泥基渗透结晶型防水涂料中的活性离子可以与钙离子形成一种溶于水的不稳定络合物,通过络合-取代反应生成不溶于水的结晶体沉淀来达到使水泥混凝土结构防水的目的.采用分光光度法对该不稳定络合物的稳定常数进行了测定.     

有机硅溶胶复合处理的锌铬膜涂层

为了进一步探索改善锌铬膜涂层性能的途径,扩大锌铬膜涂层的应用范围,采用有机硅溶胶材料对锌铬膜涂层复合处理,并进行性能测试.通过中性盐雾腐蚀、二氧化硫腐蚀、酸性介质腐蚀失重、流水喷淋冲刷前后的盐水浸泡腐蚀失重和附着力以及涂层的硬度测试,对比了锌铬膜涂层采用有机硅溶胶材料复合处理前后的性能变化.结果表明:经过复合处理后的锌铬膜涂层在中性和酸性环境条件下的耐腐蚀性能、耐流水冲刷性都有了大幅度的提高,涂层的硬度进一步增强,使锌铬膜涂层在更为广泛的领域的应用成为可能.     

阻尼材料复模量测试中的动力学分析

流变振动仪利用等截面杆的纵向简谐振动来测定材料的阻尼，十分方便和有效。本文把振动杆件作为一个连续体，指出响应（一端的应力）和激励（另一端的应变）之比（作者称之为试件复模量）不仅反映了试件的材料性质，而且与试件的动特性参数（如质量密度）和几何参数密切相关；提出了由实验得到的试件复模量得出材料复模量的计算方法。剪切简谐振动试验也有类似情况。     

复杂环境下爆破挤淤软基处理技术应用研究

在阐述爆破挤淤作用机理的基础上,介绍了复杂环境下爆破挤淤软基处理工程实例,开展了现场爆破试验和振动测试,得出了爆破地震波随距离衰减规律,从而进行了爆破参数的优化设计.工程实践表明:优化设计达到了预期的效果,爆破振动速度控制在安全范围以内,未对周围建筑设施造成危害;而且,抛石层落底标高与落底宽度达到设计要求,堤身落底达到设计规范要求.     

复杂结构高耸建筑物爆破拆除切口研究

针对壁体材料多样、结构复杂的高耸建筑物的爆破拆除,通过实验研究确定了爆破切口形式,运用力学理论推导了余留支撑体所对应的圆心角和爆破切口高度计算公式,并在工程实践中得到验证.对爆破拆除类似建筑物具有较大的实用价值.     

精密雕刻技术在复杂曲面模具加工中的应用

研究了精密雕刻技术在复杂曲面模具加工中的优势,采用非标准小刀具使精雕机床能够实现在加工中心、数控铣上无法完成的小尺寸加工.提出将精密雕刻技术应用于复杂曲面模具的加工,完成复杂曲面细小特征的加工,从而提高模具加工的速度,加快新产品开发的进度,降低开发成本,实现模具的快速制造,改变了传统的仅依靠数控铣床、加工中心进行模具制...     

The Change in the Components of the Complex Magnetic Permeability of Nonuniformly Magnetized Ferromagnetic Rods

The results of experimental investigations of demagnetizing and surface effects in extended ferromagnetic rods, magnetized by the alternating magnetic field of coils of different length in the 20 Hz – 50 kHz frequency band are presented. A physically justified explanation of the fact that the components of the complex magnetic permeability are independent of the length of the coil at the higher frequencies of this band is given.     

Nascent Polypeptide-Associated Complex Involved in the Development and Pathogenesis of Fusarium graminearum on Wheat

Reliable knowledge on pathogenic agents contributes to effective plant protection. For most plant pathogens, maintaining protein homeostasis (proteostasis) is essential for unfolding the cellular functions to survive and thrive. However, the fungal proteins involved in proteostasis remain poorly characterized in the process of pathogenesis. In this study, we characterized the function of the nascent polypeptide-associated complex (NAC) in Fusarium graminearum (F. graminearum) (FgNAC), one of the top 10 fungal pathogens with predominant scientific/economic importance. We found that FgNACα, a subunit of FgNAC, manifests high structural and functional similarity to its homologous counterparts in yeast and other species. The mutants of F. graminearum lacking NACα are viable but suffer significant defects in vegetative growth, conidial production, and pathogenesis. In addition, we show here that FgNACα can interact with another subunit of NAC (FgNACβ) in a yeast-two-hybrid assay. The subcellular localization results show that FgNACα and FgNACβ are predominantly localized in the cytoplasm. Future studies should focus on deciphering the mechanism by which NAC orchestrates protein biogenesis and consequentially modulates development and pathogenesis.     

南京民国总统府建筑群色彩谱系研究

目的 通过定性与定量相结合的调查分析建筑色彩的方法,对南京民国政治建筑进行色彩谱系的研究。方法 以日本PCCS色彩研究体系为标准,甄选出南京民国政治建筑中具有代表性的南京民国总统府建筑群作为研究载体,在自然光条件下（一般为避免日光色温对建筑色彩的测试影响,选取晴天10：00至15：00 时段进行测试）,从色彩分布、各类构件色彩特征、色彩等级、明度和色相规律等角度分析南京民国政治建筑的色彩谱系,并运用现场实体色彩取样的方法,分析建筑色彩的主体色和辅助色,研究出南京民国政治建筑的色彩特征及构成情况。结论 通过以上方法归纳提取出了南京民国建筑色彩特征和表现形式,建立了色彩数据资料,为研究、保护及修复历史建筑色彩提供现实数据资料和参考依据。     

Partition of the probability-assigned space in probability density evolution analysis of nonlinear stochastic structures

Based on a partition of probability-assigned space, a strategy for determining the representative point set and the associated weights for use in the probability density evolution method (PDEM) is developed. The PDEM, which is capable of capturing the instantaneous probability density function of responses of linear and nonlinear stochastic systems, was developed in the past few years. The determination of the representative point set and the assigned probabilities is of paramount importance in this approach. In the present paper, a partition of probability-assigned space related to the representative points and the assigned probabilities are first examined. The error in the resulting probability density function of the stochastic responses is then analyzed, leading to two criteria on strategies for determining the representative points and a set of indices in terms of discrepancy of the point sets. A two-step algorithm is proposed, in which an initial uniformly scattered point set is mapped to an optimal set. The implementation of the algorithm is elaborated. Two methods for generating the initial point set are outlined. These are the lattice point sets and the Number-Theoretical nets. A density-related transformation yielding the final point set is then analyzed. Numerical examples are investigated, where the results are compared to those obtained from the standard Monte Carlo simulation and the Latin hyper-cube sampling, demonstrating the accuracy and efficiency of the proposed approach.     

Measurement of the Appearance and Growth of Tow Buckling Defect in the Frame of Complex Shape Manufacturing Process by Using Fringe Projection Technique

During the manufacturing of composite complex shape parts, defects such as tow buckles characterised by out of plane elevation may appear. The parameters controlling the appearance and growth of the defect are not completely understood and need to be investigated. A device capable of reproducing tow buckles has been used to study the tow buckling phenomenon. Several techniques able to measure out of plane elevations are discussed to detect the appearance and evaluate continuously the growth of the tow buckle in relation to its size and shape. The fringe projection technique was chosen as it gives the best compromise between the size of the defect to measure and its resolution. If the in‐plane bending angle is the main criterion at the origin of the tow buckle appearance and growth, it is not the only one. This work shows that the fabric architecture such as the space between the tows perpendicular to the one showing the buckle is also crucial to control the buckle's appearance and growth. It also shows that the differential bi‐axial loading of the fabric as well as the stiffness of the tows in the three main directions greatly influences the appearance of the defect.     

微弧氧化与磁控溅射复合处理的钛合金表面耐磨性研究

微弧氧化处理后的钛合金,表面形成的多微孔氧化膜可使其摩擦因数降低且耐磨性得到提高,但这还不能满足某些使用要求.在微弧氧化的基础上再利用脉冲偏压式磁控溅射技术在钛合金表面沉积氮化钛涂层.球-盘磨损试验表明,与微弧氧化相比,其摩擦因数进一步降低且耐磨性进一步提高,这主要是沉积富钛氮化钛使氧化膜的微孔得到了部分或全封闭的覆盖.     

The role of maternal antibodies in the emergence of severe disease as a result of fragmentation

Population fragmentation is a major problem for the conservation of mammalian species. Since the spread of an infectious disease is related to the intensity of contacts between individuals, fragmentation destabilizes the way the parasites circulate in their host population. Recently, Zinkernagel has proposed that a reduction in the frequency of infections by a parasite could lead to the emergence of severe forms of the disease, previously avoided because the disease was contracted early in life and attenuated by maternal antibodies. However, it is still unclear whether this change in disease expression increases the global mortality it induces because the disease becomes more severe and also less frequent. Here, we use a mathematical model to link population fragmentation with the hypothesis of Zinkernagel. Firstly, we show that there is a change in the severity of the disease during the fragmentation process, especially at a local scale, suggesting that host population fragmentation could be a widespread mechanism of disease emergence. Secondly, we show that the emergence of the severe form of the disease can lead to a significant increase in its induced mortality. Finally, we determine the types of interactions for which the fragmentation of the host population could be the most dangerous.     

开放的深井开采复杂巨系统中岩爆灾害研究方法

岩爆是深井开采中的主要灾害之一。随着我国矿床开采由地表、浅部向深部转移，这一问题变得日益突出，传统的关于深井开采过程中岩爆问题的研究，由于没有或较少考虑系统整体性，按照还原论的方法进行，取得的成果与实际应用之间尚存在较大距离。文章通过对深井开采系统特征的分析研究，提出深井开采系统是一个典型的开放的复杂巨系统。对于这种系统的研究，目前行之有效的方法是采用从定性到定量的综合集成方法，将专家群体（包括地质专家、采矿专家、系统工程专家、计算机专家、岩石力学专家等）、统计数据和信息资料、计算机技术三者有机结合起来，构成一个高度智能化的以人为主、人机结合的交互系统。通过集成各种知识，获得对问题的正确的认识和理解，才能在工程实践中发挥具体的指导作用。