气相法白炭黑填充天然橡胶的裂纹扩展机理

研究了不同粒径,不同份数的白炭黑对天然橡胶(NR)裂纹生长行为的影响。采用具有裂纹生长测试功能的DMA(DMA-Crack Growth)对预割口试样的裂纹扩展速度进行测试。利用超高速显微摄像技术对裂纹扩展尖端进行在线追踪,得到裂纹扩展尖端的动态显微图像。结果表明,添加20 phr原生粒径为15 nm的气相法白炭黑时,裂纹尖端韧带均匀且细密,对裂纹生长起到很好的阻碍作用;添加20 phr原生粒径为7 nm的气相法白炭黑时,对试样的裂纹生长有不利影响。     

电气检测领域电源稳定性核查方法

产品检测中电源具有十分重要的作用,本文以电动机检测实验室为例,介绍了电器领域中电源稳定性的核查方法。     

通过预涂覆SiC优化AZ31B镁合金DE-GMAW焊缝的显微组织及提升力学性能

研究了碳化硅(SiC)颗粒涂覆量对2mm厚AZ31B镁合金双电极气体保护焊DE-GMAW焊缝的宏观形貌、显微组织和力学性能的影响。利用光学显微镜、扫描电镜和X射线衍射分析技术(XRD)对接头的显微组织、相及相的成分进行分析。同时采用维氏硬度试验计和万能试验机对焊接接头的显微硬度和抗拉强度分别进行测量。结果表明,随着SiC涂覆量的增加,焊接接头熔深和深宽比先增大后减小。XRD测试结果显示,SiC的添加并不改变焊缝中相的组成,焊缝由α-Mg和β-Mg_(17)Al_(12)组成。SiC可以细化α-Mg晶粒,打断焊缝中β-Mg_(17)Al_(12)相,起到弥散强化的效果。但SiC涂覆量达到一定值后,随着SiC涂覆量的继续增加,α-Mg晶粒粗化,β-Mg_(17)Al_(12)相的弥散强化作用不再增加。焊接接头的显微硬度和抗拉强度随着SiC涂覆量的增加先增大后减小。     

MSP430单片机的电桥平衡自调节设计

在应变式火炮膛压测试仪中,直流不平衡电桥测量电路是测量火炮膛压信号的核心环节。由于电阻应变计阻值有一定的偏差,使得电桥在初始时达不到平衡,导致测试仪在没有应变时输出信号有为负值的可能性,致使测试仪所测得的数据无法以计算机数值校正方法实现。对于传统的机械电位器,手动调节的方法无法满足应变式火炮膛压测试仪封闭式、小体积的要求。本文设计的MSP430F2002单片机和MAX5402数字电位器所构成的电桥平衡自调节电路,具有结构简单、占用空间小、功耗低、可靠性高等特性,完全符合火炮膛压测试仪的要求。1电桥平衡自调节原理在火炮膛压测试仪中,考虑到测试仪壳体结构的限制以及低功耗的要求,采用的电桥为1/4直     

Side-effect localization for lazy, purely functional languages via aspects

Many side-effecting programming activities, such as profiling and tracing, can be formulated as crosscutting concerns and be framed as side-effecting aspects in the aspect-oriented programming paradigm. The benefit gained from this separation of concerns is particularly evident in purely functional programming, as adding such aspects using techniques such as monadification will generally lead to crosscutting changes. This paper presents an approach to provide side-effecting aspects for lazy purely functional languages in a user transparent fashion. We propose a simple yet direct state manipulation construct for developing side-effecting aspects and devise a systematic monadification scheme to translate the woven code to monadic style purely functional code. Furthermore, we present a static and dynamic semantics of the aspect programs and reason about the correctness of our monadification scheme with respect to them.     

XPS文档的字形处理技术

XPS（XML Paper Specification）是微软推出的一种固定布局的电子文档格式,能达到所见即所得的打印效果。本文详细分析了XPS文档的结构、组织形式,并对其中的字形部分以解析和实现的形式进行了详细的剖析。     

Grid-based collaborative simulation system for vehicle crashworthiness

Globalization and increasing market competition are forcing the automotive industry to develop technology that will enable more efficient collaboration between carmakers and their suppliers. One of the options that can meet this demand is to adopt grid technology in the collaboration process. For the system to be successfully applied, the trust relationship among Virtual Organization (VO) members becomes a very important factor. Systems lacking in secure mechanisms require all the collaborating members to fully trust each other, and thus make their application quite limited. Based on grid technology, this paper proposes a collaborative simulation system for vehicle crash safety design, and discusses the trust relationship among VO members. The grid middleware VEGA and web services working for the collaboration also contribute to the simulation system. Also, a test bed is set up on the basis of the Local Area Network (LAN). At the end of this paper, a real case involving a carmaker and a door supplier is presented to demonstrate how the grid-based collaborative simulation system works.     

Web-based post-processing visualization system for finite element analysis

In this paper, we propose and implement a website of post-processing system for finite element analysis (WebDFEA). Finite element analysis is a computer-aided engineering tool and is popular for static/dynamic structure analysis. It includes three processing systems where post-processing system is to graphically demonstrate the analysis result of a structure model analyzed by finite element method. WebDFEA performs as a website. It is cross-platform because it can auto-detect a client computer platform and auto-download proper OpenGL API for drawing computer graphics. It can draw precise graphics on webpage which can be free controlled by the mouse as a manner in professional software. A database server is involved to store finite element model data and its analysis result. The graphic user interface (GUI) of WebDFEA is a flexible GUI comprising three parts: the switch buttons designed by HTML, the display board and the color bar both developed in Java. The three components are independent and cooperative with each other. They can be recombined without running errors for different purposes. A ship hull section with half a hatch is chosen as the study case to test WebDFEA website. Its finite element model comprises 11,442 triangle elements (shapes). The timeframe starting when WebDFEA is connected to the end when the model is demonstrated is acceptable.