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101.
结合碳纤维增强复合材料(CFRP)的高强特性及光纤光栅(OFBG)的感知特性,研制开发CFRP-OFBG智能复合板,通过试验验证其应变传感性能.完成预应力CFRP-OFBG板加固钢梁静载试验,监测钢梁的应变和屈服破坏过程,研究预应力CFRP-OFBG智能碳纤维板加固钢梁的抗弯性能.结果表明:预应力CFRP-OFBG智能碳纤维板是一种集受力和传感于一体的新型土木工程材料,克服了光纤光栅埋设的工艺问题,并且能有效提高加固钢梁的抗弯性能,具有良好的推广价值和应用前景.  相似文献   
102.
某单─银矿经浮选所得精矿(%):Agl~2,Cu≈1,Pb4~7,CaO+MgO30~35,S4~7,C8~9。研究了氰化、硫脲、氨浸等方案对该精矿浸出效果,并从浸出指标等因素进行比较,认为焙烧─预浸─氨浸方案较好,银浸出率>97%,铜浸出率95%。  相似文献   
103.
新的嵌套排样算法   总被引:4,自引:1,他引:4  
赖剑锋  王敏 《锻压技术》2003,28(5):27-29,43
以多边形定点算法原理为基础,得出了新的嵌套求解算法成功解决了优化排样问题。并以C语言程序设计为基础,使算法在计算机上得以实现。  相似文献   
104.
In shape memory materials,that have been trained to have a two way shape memory effect(TWSM),themartensitic variants are classified into two groups,i.e.,preferentially oriented variants and self-accommodatingvariants.Applied stress may promote or constrain the transition of preferentially oriented variants and so changetransformation temperatures but has no essential effect on self-accommodating variants.According to the pointof view mentioned above,some experimental phenomena during thermocycling of a TWSM device may be ex-plained,such as the absence of synchronization between the plot of resistance change.temperature and the plotof memory strain vs.temperature.  相似文献   
105.
For production of fine-grained and corrosion-resistant tungsten carbide (WC) based cemented carbides, addition of chromium carbide (Cr33C2) in small amounts is standard practice. No systematic study, however, has been made of the effects of large additions (maximum 6 wt % ) of Cr3C2 as a substitute for tungsten carbide. This study focuses on the effect of hard-phase substitution by C3C2 in WC-1OCo cemented carbide. An attempt is also made to modify the binder metal cobalt by partial or complete substitution of nickel. Specimens were prepared using the standard liquid-phase sintering process and were tested for sintered porosity, mechanical properties, corrosion resistance, and microstructural parameters. Results confirm the findings of earlier workers regarding grain refinement and improvement of mechanical properties upon the addition of small amounts (<2 wt%) of Cr3C2. Modification of the binder phase improves indentation fracture toughness and corrosion resistance. Addition of Cr3C2 independent of the binder type improves corrosion resistance.  相似文献   
106.
20钢及渗铝20钢在KCl盐膜下的腐蚀   总被引:1,自引:0,他引:1  
研究了20钢及渗铝20钢在750℃和800℃于KCl盐膜下空气中的腐蚀行为。结果显示,所有条件下20钢均发生了严重的加速腐蚀现象,形成了厚的、疏松的、与基体结合性很差的腐蚀产物膜。渗铝20钢则腐蚀增重很小。虽然渗铝试样表面致密的、连续的Al2O3对材料起到了保护作用,但在氧化膜内部同时形成了严重的内腐蚀区。从热力学角度讨论了试验结果。  相似文献   
107.
Two full 3D steady mathematical models are developed by finite element method (FEM) to calcalate coupled physics fields. the electro-magnetic model is built and solved first and so is the fluid motion model with the acquired electromagnetic force as source body forces in Navier-Stokes equations. Effects caused by the ferromagnetic shell, busbar system around, and open boundary problem as well as inside induced current were considered in terms of the magnetic field. Furthermore, a new modeling method is found to set up solid models and then mesh them entirely with so-called structuralized grids, namely hex-mesh. Examples of 75kA prebaked cell with two kinds of busbar arrangements are presented. Results agree with those disclosed in the literature and confirm that the coupled simulation is valid. It is also concluded that the usage of these models facilitates the consistent analysis of the electric field to magnetic field and then flow motion to the greater extent, local distributions of current density and magnetic flux density are very much dependent on the cell structure, the steel shell is a shield to reduce the magnetic field and flow pattern is two dimensional in the main body of the metal pad.  相似文献   
108.
研究了等离子喷涂法制备ZrO2Ti系功能梯度涂层。结果表明,采用等离子喷涂工艺制备功能梯度涂层是可行的,涂层与基体除以机械咬合方式结合外,还存在着少量冶金化学反应结合,添加Ni/Al和SiO2有助于提高涂层的结合强度  相似文献   
109.
传统的验证方法难以保证分布式K互斥算法的有效性和安全性.为解决这一问题,给出了进一步的研究,提出一种基于概率模型检测器PRISM的方法,对Kerry Raymond的分布式K互斥算法进行形式化建模与分析验证.通过设置算法中各个进程进入临界区的时间而得出的结果中发现,改变临界区的数目K,对于某一进程进入临界区的平均及时时间的影响并不大.如果某一进程的执行时间比其他进程大很多,则K的增加可以提高运行效率.最后证明了这一结论.  相似文献   
110.
Motion sensing has now become one of the crucial parts of modern life. The tech products for entertainment create huge competition in the modern market, with the front runners such as game and handset manufacturers. Users can use their own bodies to control the systems without Conversational User Interfaces (CUIs) and Graph User Interfaces (GUIs). With many benefits, the technologies of NUI is getting more and more important, which also are usually accompanied by the sensor developments. Hence, system designers uses the sensors on the embedded platforms used to develop the system devices for different body movement control interfaces, such as using the gravitational sensor to control the systems or using touchscreen detection. However most of the body movement is restricted to the hand portion for the system platform, making it not as dynamic as the traditional monitor consoles. Thus, this restriction decreases the multitude and availability of controlling modes in system devices. In this study, a sensor-based gait recognition was proposed, in order to provide a novel natural user interface for control systems except the operating modes of gesture.  相似文献   
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