Ehrenfeucht-Fraïssé games in finite set theory

In this article, with Ehrenfeucht-Fraïssé games we prove that Δ₁≠Δ₀ on BFR, which implies Δ≠Δ₀ on BFR, and thus solve an open problem raised by Albert Atserias in his dissertation (Δ₀,Δ₁,Δ are fragments of first order logic and BFR is a class of finite sets which in essence is equivalent to a class of finite pure arithmetic structures with built-in BIT predicate).     

网上书店的设计思路

本文从理论构建一个电子商务应用系统——网上书店,按照软件工程的要求,对系统进行需求分析,提出一个网上购书系统的构建思路,首先对系统功能要求及系统运行要求;其次对系统总体设计、软件结构设计、系统数据库的选择与设计;最后为软件测试。     

Extracting Takagi-Sugeno Fuzzy Rules with Interpretable Submodels via Regularization of Linguistic Modifiers

In this paper, a method for constructing Takagi-Sugeno (TS) fuzzy system from data is proposed with the objective of preserving TS submodel comprehensibility, in which linguistic modifiers are suggested to characterize the fuzzy sets. A good property held by the proposed linguistic modifiers is that they can broaden the cores of fuzzy sets while contracting the overlaps of adjoining membership functions (MFs) during identification of fuzzy systems from data. As a result, the TS submodels identified tend to dominate the system behaviors by automatically matching the global model (GM) in corresponding subareas, which leads to good TS model interpretability while producing distinguishable input space partitioning. However, the GM accuracy and model interpretability are two conflicting modeling objectives, improving interpretability of fuzzy models generally degrades the GM performance of fuzzy models, and vice versa. Hence, one challenging problem is how to construct a TS fuzzy model with not only good global performance but also good submodel interpretability. In order to achieve a good tradeoff between GM performance and submodel interpretability, a regularization learning algorithm is presented in which the GM objective function is combined with a local model objective function defined in terms of an extended index of fuzziness of identified MFs. Moreover, a parsimonious rule base is obtained by adopting a QR decomposition method to select the important fuzzy rules and reduce the redundant ones. Experimental studies have shown that the TS models identified by the suggested method possess good submodel interpretability and satisfactory GM performance with parsimonious rule bases.     

Learning in an Ambient Intelligent World: Enabling Technologies and Practices

The rapid evolution of information and communication technology opens a wide spectrum of opportunities to change our surroundings into an Ambient Intelligent (AmI) world. AmI is a vision of future information society, where people are surrounded by a digital environment that is sensitive to their needs, personalized to their requirements, anticipatory of their behavior, and responsive to their presence. It emphasizes on greater user friendliness, user empowerment, and more effective service support, with an aim to bring information and communication technology to everyone, every home, every business, and every school, thus improving the quality of human life. AmI unprecedentedly enhances learning experiences by endowing the users with the opportunities of learning in context, a breakthrough from the traditional education settings. In this survey paper, we examine some major characteristics of an AmI learning environment. To deliver a feasible and effective solution to ambient learning, we overview a few latest developed enabling technologies in context awareness and interactive learning. Associated practices are meanwhile reported. We also describe our experience in designing and implementing a smart class prototype, which allows teachers to simultaneously instruct both local and remote students in a context-aware and natural way.     

利用Excel巧妙处理学生成绩

用Excel可高效处理学生成绩,介绍了表格的设计、相关公式的使用和模板的制作.     

基于OpenGL的导弹试验模拟器仿真研究

基于OpenGL进行导弹飞行过程仿真,研究了交互界面的设计技术、特殊效果产生技术、模型的数据驱动及视点变化技术和碰撞检测技术.     

Effect of the modulation transfer function of a digital image-acquisition device on phase-measuring profilometry

Systematic errors in phase-measuring profilometry that are introduced by the modulation transfer function of a digital image-acquisition device are analyzed. New phase expressions and phase-deviation formulas are given. The results for simulations and experiments demonstrate that the algorithm of phase-measuring profilometry cannot be regarded as a point-to-point operation. To obtain precise results, an optimum scheme for setting the measurement system is also proposed.     

Coplanar refractive-diffractive doublets for optoelectronic integrated systems

A coplanar refractive-diffractive doublet array employing surface-relief diffractive phase elements embedded within poly(methyl methacrylate) microlenses is introduced as an optomechanical building block for optoelectronic integrated systems. The design method, fabrication technology, and results are described. Coplanarity of the quadratic- and linear-phase elements constituting the doublet can reduce optomechanical complexity in applications to unguided optical interconnects.     

Stability of three-dimensional metallic glass Ni68B21Si11

Under isothermal and linear heating conditions, the thermal stability of the three-dimensional metallic glass Ni₆₈B₂₁Si₁₁, produced by rapid quenching of the denucleated melt (RQDM), has been systematically studied using PE DSC7 differential scanning calorimetry in relation to denucleation of liquid alloy prior to rapid quenching, pre-anneal treatment of amorphous specimens, and cooling rate. The following results were observed. First, the thermal stability of metallic glass prepared by RQDM is obviously enhanced because of the removal of pre-existing nuclei in advance. This is substantiated by the experimental data showing that the projected life of three-dimensional metallic glass Ni₆₈B₂₁Si₁₁ is increased by an order of magnitude at 400 K. Secondly, pre-anneal treatment of the amorphous alloy leads to a reduction of temperature for the onset of crystallization,T _x, and crystallization heat, H. Finally, quenching rates have little effect on the thermal stability of amorphous alloys.