Experimentation and thermodynamic modelling on SrZrO_3

Experimental data for the perovskite phase SrZrO3 were subjected to a critical thermodynamic assessment using the CALPHAD approach. Special attention was paid to the structural behavior of SrZrO3 to illustrate, how to select an appropriate thermodynamic model based on crystal structure and chemistry information, how to identify and resolve the inconsistency between various kinds of experimental data, and how to use thermodynamic modeling as a basic tool in the development and optimization of materials and process. Our assessment results in a Gibbs energy function covering the temperature range between 300 K and the melting point, which explains the experimental data within the experimental uncertainty.     

Designing System Dualities: Characterizing a Web-Supported Professional Development Community

In this article we focus on the challenges we have encountered in attempting to support the development of an online community of practice for grade 5-12 mathematics and science teachers. Specifically, this project involves the design and evaluation of an electronic knowledge network, the Inquiry Learning Forum (ILF), a web-based professional development system designed to support a community of practice (CoP) of in-service and preservice mathematics and science teachers who are creating, reflecting upon, sharing, and improving inquiry-based pedagogical practices. This research examines the interplay among a variety of variables that characterize the dynamics of building a social network through which participating teachers will seek to share and improve their pedagogical practices. Our research suggests that designing for virtual communities involves balancing and leveraging complex dualities from the "inside" rather than applying some set of design principles from the "outside." This research provides an illuminative case study from which others can more readily identify patterns occurring in their own interventions and navigate the challenges they face more intelligently.     

匀鞭蚜小蜂(Encarsia sp.)扫描电镜观察 Ⅰ.成虫足的形态及感器

匀鞭蚜小蜂3对足的特点是:3对足的基节均具有相同数量的指状感器,转节上具有同样的盘状感器。前足胫节及基跗节发达,并有触角清洁器。后足腿节粗壮,便于跳跃。     

A tunable fuzzy logic controller for the vehicle semi-active suspension system

On the basis of analyzing the system constitution of vehicle semi-active suspension,a 4-DOF(degree of freedom)dynamic model is established.A tunable fuzzy logic controller is designed by using without quantification method and taking into account the uncertainty,nonlinearity and complexity of parameters for a vehicle suspension system.Simulation to test the performance of this controller is performed under random excitations and definite disturbances of a C grade road,and the effects of time delay and changes of system parameters on the vehicle suspension system are researched.The numerical simulation shows that the performance of the designed tunable fuzzy logic controller is effective,stable and reliable.     

Wavelet packet decomposition entropy threshold method for discrete spectrum interferences rejection of on-line partial discharge monitoring

1. Introduction For suppressing discrete spectrum interference (DSI) in partial discharge (PD) signals, the presently wide-used approaches are hardware filters and Fourier transform based digital notch filters [1], which, definitely having gained effect in some extent, lead to relatively large energy loss of original PD signals and the preset parameters wont work when new interference appears or some center frequency changes. Adaptive filters [2] adjust parameters automatically with poor st…     

柑桔红圆蚧与三种寄生蜂相互作用系统的动态研究

本文建立了红圆蚧(Aonidiella aurantii)与3种寄生蜂:盾蚧长缨蚜小蜂(Encarsia citrina)、岭南黄蚜小蜂(Aphytis lingnanensis)和印巴黄蚜小蜂(Aphytis melinus)相互作用的系统模型。按红圆蚧的面积大小分成3种类型,分析了三维系统和四维系统在不同红圆蚧大小分布条件下,系统的动态变化。确定了寄生物共存和相互排斥的边界条件,为红圆蚧的生物防治决策提供理论依据。     

Experiments on Deflecting & Oscillating Waterjet

A new type jet, the oscillating & deflecting jet, is put forward and its oscillating and deflecting characteristics are investigated. The nozzle of the self-oscillating & deflecting water jet consists of an upstream nozzle, a downstream nozzle, an oscillating chamber and two switches. It is experimentally shown that the deflective angle may reach 9.53 degree. The generated pressure fluctuation is very regular and the jet can efficiently increase the ability for breaking and cutting by eliminating the water cushion effect associated with a continuous jet.     

斜纹夜蛾幼虫血细胞的种类及其离体变化研究

本文详细描述了斜纹夜蛾幼虫各种血细胞的光学形态及超微结构。血细胞可分为原细胞、浆细胞、颗粒细胞、小球细胞、凝集细胞和类绛色细胞。原细胞分化为浆细胞进而发育为颗粒细胞的衍化关系明显;小球细胞、凝集细胞和类绛色细胞离体后可将内中物释放至血浆中。同时对小球细胞和类绛色细胞的功能作了讨论。