Current–Voltage Characteristics in Individual Polypyrrole Nanotube, Poly(3,4-ethylenedioxythiophene) Nanowire, Polyaniline Nanotube, and CdS Nanorope

In this paper, we focus on current–voltage (I–V) characteristics in several kinds of quasi-one-dimensional (quasi-1D) nanofibers to investigate their electronic transport properties covering a wide temperature range from 300 down to 2 K. Since the complex structures composed of ordered conductive regions in series with disordered barriers in conducting polymer nanotubes/wires and CdS nanowires, all measured nonlinear I–V characteristics show temperature and field-dependent features and are well fitted to the extended fluctuation-induced tunneling and thermal excitation model (Kaiser expression). However, we find that there are surprisingly similar deviations emerged between the I–V data and fitting curves at the low bias voltages and low temperatures, which can be possibly ascribed to the electron–electron interaction in such quasi-1D systems with inhomogeneous nanostructures.     

模糊粗糙数据模型:一种数据分析的新方法

提出了一种数据分析的新方法——模糊粗糙数据模型（Fuzzy Rough Data Model,FRDM）.该方法采用动态自适应模糊聚类技术,将Kowalczyk方法中的粗糙数据模型（Rough Data Model,RDM）对输入数据空间的网格状“硬划分”转化为模糊划分,辨识输入数据空间中的模糊模式类,并通过定义各模糊模式类与决策类别之间的类型映射关系ftype：Ci→y,以及输入数据对各模式类分类规则的匹配度（Degree of Fulfillment,DoF（x））概念,建立起相应的FRDM模型.不同数据集的实验测试结果表明,与Kowalczyk的RDM方法相比,文中方法具有更好的数据概括能力、更强的噪声数据处理能力和更高的搜索效率.     

空间微重力下植物栽培水分养分控制研究

通过"天宫2号"空间实验室搭载的空间植物栽培装置,研究了微重力下植物栽培水分养分控制技术.针对空间微重力特点,设计了植物栽培水分养分传导结构,并验证了其可行性和合理性.生菜在空间实验室微重力环境下的顺利萌发、生长发育,证明了水分养分传导结构的合理性和可行性,为后续开展更大规模的空间植物栽培奠定了基础.通过实验,了解了空间微重力下水分养分的传导和分布规律,为研究空间植物栽培水分养分供应方法和测试方法提供了依据.     

分类分析中基于信息论准则的特征选取

Feature selection aims to reduce the dimensionality of patterns for classificatory analysis by selecting the most informative instead of irrelevant and/or redundant features. In this study, two novel information-theoretic measures for feature ranking are presented: one is an improved formula to estimate the conditional mutual information between the candidate feature fi and the target class C given the subset of selected features S, i.e., I(C;fi|S), under the assumption that information of features is distributed uniformly; the other is a mutual information (MI) based constructive criterion that is able to capture both irrelevant and redundant input features under arbitrary distributions of information of features. With these two measures, two new feature selection algorithms, called the quadratic MI-based feature selection (QMIFS) approach and the MI-based constructive criterion (MICC) approach, respectively, are proposed, in which no parameters like β in Battiti's MIFS and (Kwak and Choi)'s MIFS-U methods need to be preset. Thus, the intractable problem of how to choose an appropriate value for β to do the tradeoff between the relevance to the target classes and the redundancy with the already-selected features is avoided completely. Experimental results demonstrate the good performances of QMIFS and MICC on both synthetic and benchmark data sets.     

Study on robust H �� filtering in networked environments

 This paper is concerned with the robust H_∞ filter problem for networked environments, which are subject to both transmission delay and packet dropouts randomly. By employing random series which have Bernoulli distributions taking value of 0 or 1, the data transmission model is obtained. Based on state augmentation and stochastic theory, the sufficient condition for robust stability with H_∞ constraints is derived for the filtering error system. The robust filter is designed in terms of feasibility of one certain linear matrix inequality (LMI), which is formed by adopting matrix congruence transformations. A numerical example is given to show the effectiveness of the proposed filtering method.     

化工多变量时滞过程的频域解耦控制设计的研究进展

化工多变量时滞过程的频域解耦控制设计方法在工程实践中被广泛采用,是过程控制领域中的一个重要研究方向。本文根据近些年来这一研究方向上的主要研究成果,简要地概述了具有主导影响的几种频域解耦控制结构及其整定方法的研究进展,分析和讨论了它们各自的主要优缺点,然后指出了一些当前化工实践中具有迫切要求的相关研究课题。     

Functional Annotation of Proteomic Data from Chicken Heterophils and Macrophages Induced by Carbon Nanotube Exposure

With the expanding applications of carbon nanotubes (CNT) in biomedicine and agriculture, questions about the toxicity and biocompatibility of CNT in humans and domestic animals are becoming matters of serious concern. This study used proteomic methods to profile gene expression in chicken macrophages and heterophils in response to CNT exposure. Two-dimensional gel electrophoresis identified 12 proteins in macrophages and 15 in heterophils, with differential expression patterns in response to CNT co-incubation (0, 1, 10, and 100 μg/mL of CNT for 6 h) (p < 0.05). Gene ontology analysis showed that most of the differentially expressed proteins are associated with protein interactions, cellular metabolic processes, and cell mobility, suggesting activation of innate immune functions. Western blot analysis with heat shock protein 70, high mobility group protein, and peptidylprolyl isomerase A confirmed the alterations of the profiled proteins. The functional annotations were further confirmed by effective cell migration, promoted interleukin-1β secretion, and more cell death in both macrophages and heterophils exposed to CNT (p < 0.05). In conclusion, results of this study suggest that CNT exposure affects protein expression, leading to activation of macrophages and heterophils, resulting in altered cytoskeleton remodeling, cell migration, and cytokine production, and thereby mediates tissue immune responses.     

Superconductivity of Ga-In-Sn liquid alloy

Journal of Materials Science: Materials in Electronics - The superconductor was first discovered in liquid metal Hg. Since then, the researches about superconductors have mainly focused on solid...     

航空原位集成涡流无损检测系统

综合应用多种无损检测手段以提高检测概率（POD）是无损检测的研究热点,航空飞机的外场检测也对检测仪器的快速化、智能化、集成化和原位化提出了更高的要求。在提出了涡流无损检测通用原理层模型和功能层模型的基础上,介绍了一种新型集成涡流无损检测系统。该系统融合常规涡流、脉冲、ACFM、多频以及阵列涡流无损检测五种功能,采用双总线（PCI和I2C）实现系统的模块化、可重构的系统硬件体系架构,以虚拟仪器为设计指导思想,具备通用的硬件平台和软件资源配置功能。不仅具备单一的涡流检测能力和精度,还具有通用的数据处理接口和硬件平台,便于不同检测方法结果的深层次融合及处理,是真正意义上的集成涡流无损检测系统。