一种数字影像地图无损水印方案(英文)

A lossless digital watermarking scheme,which was zero- perturbation on the content and graphics for the digital image maps,is proposed.During the simulation,the scheme has been utilized to model the copyright protection program as a commerce application.Compared to the traditional digital watermarking schemes,our scheme operates in redundancy areas of maps and is scalable to topology changes.Experimental results show that,with respect to the geometric attacks and image transformed,the performance of our scheme is better than the classical algorithms based space or frequency domain with much lower complexity..     

基于BP神经网络和3D加工图的Ti2041合金的热变形行为研究

通过热压缩实验研究了Ti2041合金的流动行为。利用BP神经网络建立的合金本构模型,具有较高的精度,其相关系数达到0.99613,平均相对误差为4.498%,预测值偏差在10%以内的数据点达92.98%。在实验数据的基础上,研究了应变速率敏感因子、功率耗散和失稳参数。建立了加工图,通过加工图的预测和显微组织观察,失稳区主要为局部流动（650~775℃/0.056~1s-1）和机械失稳（825~900℃/0.056~1s-1）,稳定区的变形机制主要为动态再结晶。结果表明：合适的变形参数为：变形温度760~825℃/825~900℃,应变速率0.001~0.01s-1/0.0032~0.056s-1。     

Development of High Strength and Toughness Non-Heated Al–Mg–Si Alloys for High-Pressure Die-Casting

Based on the 3 factors and 3 levels orthogonal experiment method, compositional effects of Mg, Si, and Ti addition on the microstructures, tensile properties, and fracture behaviors of the high-pressure die-casting Al-x Mg-y Si-z Ti alloys have been investigated. The analysis of variance shows that both Mg and Si apparently infl uence the tensile properties of the alloys, while Ti does not. The tensile mechanical properties are comprehensively infl uenced by the amount of eutectic phase(α-Al + Mg_2Si), the average grain size, and the content of Mg dissolved into α-Al matrix. The optimized alloy is Al-7.49 Mg-3.08 Si-0.01 Ti(wt%), which exhibits tensile yield strength of 219 MPa, ultimate tensile strength of 401 MPa, and elongation of 10.5%. Furthermore, contour maps, showing the relationship among compositions, microstructure characteristics, and the tensile properties are constructed, which provide guidelines for developing high strength and toughness Al–Mg–Si–Ti alloys for high-pressure die-casting.     

Oruxmaps软件在电网项目的应用

介绍了UTM坐标系,以电网项目应用为实例,阐述了Oruxmaps软件结合Google Earth应用于电网项目勘测的准备工作和具体过程.     

Recent advances with the scanning proton microprobe

The scanning proton microprobe has established itself as an essential tool for quantitative and trace elemental microscopical analysis and for nondestructive depth profiling, This paper discusses the major strengths and limitations of the instrument, the advances that have been made and the directions in which instrumental research is progressing to enable further improvements in probe performance. Recent applications in medical and in semi-conductor research are presented in order to illustrate the significance of these improvements.     

Additive Composition of Supervised Self-Organizing Maps

The learning of complex relationships can be decomposed into several neural networks. The modular organization is determined by prior knowledge of the problem that permits to split the processing into tasks of small dimensionality. The sub-tasks can be implemented with neural networks, although the learning examples cannot be used anymore to supervise directly each of the networks. This article addresses the problem of learning in a modular context, developing in particular additive compositions. A simple rule allows defining efficient training, and combining, for example, several Supervised-SOM networks. This technique is important because it introduces interesting generalizations in many modular compositions, permitting data fusion or sequential combinations of neural networks. This revised version was published online in August 2006 with corrections to the Cover Date.     

对Ag/Cu薄膜退火应力的模拟

采用基片曲率法测量并研究了Ag／Cu薄膜的应力与温度的关系．初始应力为-250MPa压应力，退火后为370MPa拉应力．采用基于形变机制图的模型模拟了应力与温度关系的实验曲线，结果表明，温度和应力不同，在薄膜内起作用的主要形变机制也不同．可能的形变机制包括位错滑移、幂律蠕变以及扩散蠕变机制．薄膜比块体材料的应变速率低，在同样的应力下应变更加困难．在退火过程中，薄膜内先使应力松弛的是Ag，将Ag各蠕变机制中的激活能提高到块体材料的1.25～1.35倍，模拟曲线与实验曲线符合得很好。     

On the Computation of Observers in Discrete-Event Systems

The concept of observer was introduced in previous work by the authors on a hierarchical control theory of discrete-event systems (DES). It was shown that the observer property of the “causal reporter” map, which in this theory models information flow in a hierarchical DES, plays a role in ensuring that a nonblocking supervisor at a given level of a hierarchy does not cause blocking in the level below. In this paper, we investigate the following problem: Given a causal reporter map that is not an observer, how can we design an observer by modifying this map? In case the latter is represented by a finite Mealy automaton, an effective computational algorithm is developed for computing an observer with the coarsest possible equivalence kernel that is finer than that of the given map. Three examples are provided for illustration.     

噪音相位图中强莫尔条纹密度和方位的研究

本文采用一种自动条纹分析的预处理方法，对噪音相应图中的莫尔条纹密度和方向的估计进行了分析研究。这些信息能用来构造相位-跳转-保存-过滤方法，提高二维展开相位法的性能以及可以使用坚固片断的相位数据。这种方法的特点是：对噪音反应非常灵敏，测试和参数的估算都要在在傅里叶范围内进行并可以做成模型用于估算研究。     

八碳烯分离过程的脱水研究

本文运用残余曲线图对八碳烯分离过程进行了分析研究,提出了采用非均相共沸精馏的方法脱除待分离物系中的水的新工艺。研究结果表明,该方法即节省了原工艺中脱水所需的一些设备,又降低了分离能耗,并且可大幅度提高脱水效率,改善产品质量。