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21.
时效对接触线用Cu-Ag-Cr合金性能的影响   总被引:3,自引:0,他引:3  
分析了固溶温度、时效及时效前冷变形量对Cu - 0 1 %Ag - 0 1 %Cr接触线用合金性能的影响 ,结果表明 :经 870℃固溶、 40 %~ 5 0 %冷变形及 480℃× 1 5h时效处理后 ,合金可获得良好的综合性能。  相似文献   
22.
学位具有学术价值、教育价值、管理价值等本体性价值,也具有个体价值与社会价值、工具性价值和目的性价值等派生性价值。当前人们在学位价值取向上存在着一些明显的错位和偏差。其具体表现有四点:一是重学位的“派生”性价值,轻学位的“本体”性价值;二是过分强调学位的教育价值和管理价值,而缺乏对学术价值应有地位的肯定;三是重学位的社会价值,轻学位的个体价值;四是重学位的工具性价值而忽视学位的目的性价值。导致这种错位现象产生的原因,不仅有教育系统内部因素,而且也与中国传统文化价值观和当前社会对人才的选拔、聘用政策有着直接的关系。  相似文献   
23.
通过对职称评定过程中专家抽取流程和原则的分析,针对人工抽取的弊端,使用Excel及VBA设计实现了一个操作简单、维护方便的专家抽取系统。实践证明该系统运行可靠性强,有效提高了工作效率,真正实现了专家抽取的公开、公正和公平性。  相似文献   
24.
王康 《现代计算机》2011,(27):10-13
针对水稻空壳率的自动化检测问题,采用机器视觉技术,设计一种实验设备,利用稻谷的透光性,使用普通可见光照射,对获得的图像进行分析处理,并比较采用灰度特征以及YUV颜色模型两种方法进行统计的结果,表明该设备和相关图像处理算法完全可以胜任空壳率的自动统计工作,为后续发展实际的应用设备奠定基础。  相似文献   
25.
The recent evolution of wireless sensor networks have yielded a demand to improve energy-efficient scheduling algorithms and energy-efficient medium access protocols. This paper proposes an energy-efficient real-time scheduling scheme that reduces power consumption and network errors on dual channel networks. The proposed scheme is based on a dynamic modulation scaling scheme which can scale the number of bits per symbol and a switching scheme which can swap the polling schedule between channels. Built on top of EDF scheduling policy, the proposed scheme enhances the power performance without violating the constraints of real-time streams. The simulation results show that the proposed scheme enhances fault-tolerance and reduces power consumption.  相似文献   
26.
Zhou  Kang  Guo  Chi  Zhang  Huyin 《The Journal of supercomputing》2022,78(7):9907-9933
The Journal of Supercomputing - We argue the agent’s low generalization problem for searching target object in challenging visual navigation could be solved by "how" and...  相似文献   
27.
All‐solution processed, high‐performance wearable strain sensors are demonstrated using heterostructure nanocrystal (NC) solids. By incorporating insulating artificial atoms of CdSe quantum dot NCs into metallic artificial atoms of Au NC thin film matrix, metal–insulator heterostructures are designed. This hybrid structure results in a shift close to the percolation threshold, modifying the charge transport mechanism and enhancing sensitivity in accordance with the site percolation theory. The number of electrical pathways is also manipulated by creating nanocracks to further increase its sensitivity, inspired from the bond percolation theory. The combination of the two strategies achieves gauge factor up to 5045, the highest sensitivity recorded among NC‐based strain gauges. These strain sensors show high reliability, durability, frequency stability, and negligible hysteresis. The fundamental charge transport behavior of these NC solids is investigated and the combined site and bond percolation theory is developed to illuminate the origin of their enhanced sensitivity. Finally, all NC‐based and solution‐processed strain gauge sensor arrays are fabricated, which effectively measure the motion of each finger joint, the pulse of heart rate, and the movement of vocal cords of human. This work provides a pathway for designing low‐cost and high‐performance electronic skin or wearable devices.  相似文献   
28.
通过对圆柱齿轮流量计进行二维简化建模,用Fluent仿真软件的ICEM CFD模块进行网格划分,利用Fluent仿真软件对圆柱齿轮流量计进行了计算和密封性的仿真分析,得出了其速度矢量分布图,并且给出了各泄漏量的计算公式和每种泄漏所占泄漏总量的百分比,即为以后的整个流量计的设计提供理论依据。,提高流量计的寿命具有重要意义。同时还省去了大量的人工计算过程,极大地加快了计算速度。  相似文献   
29.
Biologically and environmentally resorbable electronic devices support application possibilities that cannot be addressed with conventional technologies. This paper presents highly conductive, water-soluble composites that can be printed to form contacts, interconnects, antennas, and other important features that are essential to nearly all systems of this type. An optimized material formulation involves in situ polymerization to yield a polyanhydride containing a dispersion of molybdenum microparticles at appropriate concentrations. Comparisons of essential physical and electrical properties of these materials to those of composites formed with other polymers and other metal microparticles reveal the relevant considerations. Various functional demonstrations of screen-printed test structures and devices illustrate the suitability of these conductive inks for use in water-soluble electronic devices. A key advantage of the material introduced here compared to alternatives is its ability to maintain conductance over significant periods of time while immersed in relevant aqueous solutions. Studies involving live animal models establish the biocompatibility.  相似文献   
30.
Crystalline zinc oxide particles of nanometre size (< 20 nm) particles were produced from a zinc acetate solution by using a filter expansion aerosol generator (FEAG). The FEAG is an aerosol generator that is operated at 60 torr reactor pressure and produces droplets of around 2 m. The shape of the particles produced by the FEAG were distinctively different from those produced by the ultrasonic spray source (USS). Results from scanning electron microscopy (SEM) and X-ray diffractometry (XRD) indicated that crystalline zinc oxide particles of nanometre size were produced at 600 °C in 0.02 s residence time. Weight loss of these particles, determined by thermogravimetric analysis (TGA), was 3 wt%. Based on the morphology change as a function of the reactor temperature and solute concentration, we proposed that the nanometre particles were formed by uniform precipitation at the drying stage and decomposition followed by disintegration into nanometre particles. It was also shown that exothermic decomposition of the solute was not required for the disintegration of the primary particles in the FEAG process. This result opened up an opportunity for producing carbon-free nanometre particles from nitrate salts by using the FEAG.  相似文献   
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