Exponential stability of simultaneously triangularizable switched systems with explicit calculation of a common Lyapunov function

In this note, a common quadratic Lyapunov function is explicitly calculated for a linear hybrid system described by a family of simultaneously triangularizable matrices. The explicit construction of such a function allows not only obtaining an estimate of the convergence rate of the exponential stability of the switched system under arbitrary switching but also calculating an upper bound for the output during its transient response. Furthermore, the presented result is then extended to the case where the system is affected by parametric uncertainty, providing the corresponding results in terms of the nominal matrices and uncertainty bounds.     

A common fixed point theorem for compatible quasi contractive self mappings in metric spaces

A common fixed point theorem for weakly commuting quasi contractive self mappings with contracting orbital diameters in metric spaces [V. Berinde, A common fixed point theorem for quasi contractive type mappings, Ann. Univ. Sci. Budapest. 46 (2003) 81-90] is extended to the more general class of compatible quasi contractive self mappings. Our result does extend and generalize numerous related results in literature.     

On the Drazin inverse of block matrices and generalized Schur complement

In this paper, we give an additive result for the Drazin inverse with its applications, we obtain representations for the Drazin inverse of a 2 × 2 complex block matrix having generalized Schur complement S=D-CA^DB equal to zero or nonsingular. Several situations are analyzed and recent results are generalized [R.E. Hartwig, X. Li, Y. Wei, Representations for the Drazin inverse of a 2×2 block matrix, SIAM J. Matrix Anal. Appl. 27 (3) (2006) 757-771].     

Complement activation by sulfonated poly(ethylene glycol)-acrylate copolymers through alternative pathway

Previously, novel poly(ethylene glycol) (PEG) and sulfonated PEG acrylate (PEG-SO₃A/OA) copolymers were prepared as coating and/or blending materials for biomedical applications. Surfaces modified with copolymers exhibited increased anti-coagulation properties and decreased plasma adsorption level due to increased hydrophilic properties and reorientation characteristics of PEG/PEG-SO₃A chains in water phase. As continuation study, anti-complement effects of PEG-SO₃/OA copolymers were investigated in vitro, and compared with those of low-density polyethylene (LDPE) and PEG/OA. C3 activation by PEG-SO₃/OA samples was lower than that by PEG/OA samples, which was attributed to decreased surface nucleophile level of samples. PEG-SO₃/OA samples increased inhibition of Bb production, resulting in decreased C5 activation. Owing to reduced activations of C3 and C5, PEG-SO₃/OA samples markedly decreased SC5b-9 levels in plasma.     

基于S1000D标准的技术出版物公用信息管理研究

为解决飞机技术出版物中公用信息的管理问题,提高信息的重用性和数据交换的便利性。通过对S1000D标准中公用信息库(CIR)概念的介绍,结合CIR在某大型客机维修类技术出版物编写中的实际应用情况,具体说明了CIR在公用数据管理、技术出版物编写、数据交换方面的优势,及其在提高技术出版物质量方面所起的重要作用。     

Group invertible block matrices

Let M=(ABCD) (A and D are square) be a 2 × 2 block matrix over a skew field, where A is group invertible. Let S=D-CA^#B denote the generalized Schur complement of M. We give the representations and the group invertibility of M under each of the following conditions:(1)S=0; (2) S is group invertible and CA^πB=0, where A^π=I-AA^#. And the second result generalizes a result of C. Bu et al. [Appl. Math. Comput., 2009, 215: 132–139]     

Effect of trabecular bone material properties on ultrasonic backscattering signals

In this study, ultrasonic backscattering signals in cancellous bones were obtained by finite difference time domain （FDTD） simulations, and the effect of trabecular material properties on these signals was analyzed. The backscatter coefficient （BSC） and integrated backscatter coefficient （IBC） were numerically investigated for varying trabecular bone material properties, including density, Lame coefficients, viscosities, and resistance coefficients. The results show that the BSC is a complex function of trabecular bone density, and the IBC increases as density increases. The BSC and IBC increase with the first and second Lame coefficients. While not very sensitive to the second viscosity of the trabeculae, the BSC and IBC decrease as the first viscosity and resistance coefficients increase. The results demonstrate that, in addition to bone mineral density （BMD） and microarchitecture, trabecular material properties significantly influence ultrasonic backseattering signals in cancellous bones. This research furthers the understanding of ultrasonic backscattering in cancellous bones and the characterization of cancellous bone status.     

Similarity in soft set theory

We introduce and study the concept of similarity between soft sets, which is an extension of the equality for soft set theory. We also introduce the concepts of conjunction parameter (α∧β) and disjunction parameter (α∨β) of ordered pair parameter 〈α,β〉 for soft set theory, and we investigate modified operations of soft set theory in terms of ordered parameters.     

Common fixed point theorem for hybrid generalized multi-valued contraction mappings

In this paper, we introduce the notion of a hybrid generalized multi-valued contraction mapping and establish the common fixed point theorem for this mapping. Our results generalize, unify, extend and complement several common fixed point theorems of many authors in the literature.     

ICP-MS测定血中镁、铜、铅浓度时的基体效应单一内标校正方法研究

ICP-MS测定模拟全血基体中不同质量段的Mg, Cu, Pb元素,考察基体效应对测定值的影响,分别采用传统内标法和单一内标CAIS方法(common analyte internal standardization)对其进行校正和比较。结果表明CAIS方法适用于不同浓度血液基体中多种元素的同时校正,且效果良好,其相对平均误差仅为3.05%,明显低于传统内标法的12.39%和校正前的23.91%;CAIS方法不受内标元素和被测元素质量数差异、测定强度差异以及电极电位差异的限制;使用全血和血清标准物质对CAIS方法可靠性进行验证,测定值全部落在标准值范围内。