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991.
针对高复杂度芯片的生产制造缺陷难以进行充分测试的难题,文中将Mentor公司的4款可测性设计软件集成到芯片前端设计开发流程中,构建相应的设计开发环境。基于此开发环境设计AES算法硬件单元的过程表明,可测试性设计工具能相互配合,很好地支持复杂电路,辅助设计人员正确生成存储器内建自测试电路、边界扫描电路、内部扫描链等多种测试电路,提高了电路的可测试性。 相似文献
992.
本文给出了一种分析微带印刷天线辐射与散射的数值方法。此方法将印刷天线按三角网格剖分,在导体表面建立积分方程,用全波离散镜像理论给出微带结构的空域格林函数的闭合表达式,未知电流用三角网格上的矢量电流基函数展开并用矩量法求解。与以往的矩形网格上基函数展开相比,此方法能更有效地逼近任意形状的微带结构,最后给出了几个数值结果 相似文献
993.
We propose a novel refractive index sensor based on Michelson interferometer by using double-core microfiber. Through the reflection of the end and taper of double-core fiber (DCF), the Michelson interference spectrum is formed. Owing to the structure characteristic of double-core microfiber, this interferometer can achieve the measurement of refractive index (RI) and temperature. The experimental results show that the refractive index sensitivity of the interferometer is 2 377.80 nm/RIU at the diameter of the taper waist of 8.76 µm. In the temperature ranges from 30 °C to 60 °C, the temperature sensitivity is 0.070 48 nm/°C. This sensor has the advantage of high refractive index sensitivity. 相似文献
994.
995.
Simultaneous Activation of Short‐Wave Infrared (SWIR) Light and Paramagnetism by a Functionalized Shell for High Penetration and Spatial Resolution Theranostics 下载免费PDF全文
Liyi Ma Yuxin Liu Lidong Liu Anqi Jiang Fang Mao Dongdong Liu Lu Wang Jing Zhou 《Advanced functional materials》2018,28(6)
Nanoparticle emitting short‐wave infrared (SWIR) light has received increased attention in the molecular imaging field due to its deeper tissue penetration, fast imaging, high sensitivity, and resolution. The simultaneously activated SWIR excited directly by an 808 nm laser and T1‐weighted magnetic resonance imaging (MRI) signal are found in one single‐shell nanoparticle NaErF4@NaGdF4 (Er@Gd), which is used as a dual‐modality imaging contrast agent in vivo to accurately determine the position of tumors. The conjugated cypate is then aggregated on the surface of Er@Gd@SiO2‐Cy/bovine serum albumin. With the guidance of dual modality imaging, photothermal therapy is effectively used to ablate tumors in a mouse model. The design of single‐shell nanomaterial activation of SWIR imaging and MRI signals is expected to provide a new strategy for high penetration and spatial resolution cancer theranostics. 相似文献
996.
利用幅度特性对数字信号调制方式进行识别 总被引:1,自引:0,他引:1
数字调制方式的识别对于通信信号分析有着重要的作用。针对数字信号(2ASK,4ASK,2PSK,4PSK,2FSK和4FSK)的调制方式,本文提出了一种只利用调制信号瞬时幅度特性便可以对调制信号进行识别的新算法,利用特征参数提取与决策树分类器结合对以上6种数字信号进行调制识别。首先提出了使用希尔伯特变换和解析函数对数字信... 相似文献
997.
The nanomechanical characteristics of polycarbonate (PC) polymer were investigated by atomic force microscope (AFM) and nanoindentation. Scratching, wear properties, hardness and Young's modulus were obtained. The relationships between scribing feed and speed, surface depth and roughness and applied load were also investigated. The results indicated that as the applied load was increased, the furrow depth and the surface roughness increased. When the scribing feed was increased, the depth and roughness decreased. Increasing the furrow speed also decreased the surface roughness. The applied load is more significant than the scribing speed on the material removal rate. In addition, the Young's modulus and hardness of the polycarbonate material were 1.8 and 0.2 GPa, respectively. 相似文献
998.
提出了一种重影消除自适应均衡芯片设计.该芯片采用自适应算法、内置576抽头数字滤波器,可完成重影消除的所有功能。芯片高度集成,内嵌DSP控制器、存储器、同步检测器、D/A、A/D及用户编程。该芯片采用3.3V电源电压、0.35μm CMOS工艺生产制造,80-pin的QFP封装;在典型工作频率下最大功耗为1.3W。 相似文献
999.
1000.
This investigation prepares a low-resistivity and self-passivated Cu(In) thin film. The dissociation behaviors of dilute Cu-alloy
thin films, containing 1.5–5at.%In, were prepared on glass substrates by a cosputter deposition, and were subsequently annealed
in the temperature range of 200–600 °C for 10–30 min. Thus, self-passivated Cu thin films in the form In2O3/Cu/SiO2 were obtained by annealing Cu(In) alloy films at an elevated temperature. Structural analysis indicated that only strong
copper diffraction peaks were detected from the as-deposited film, and an In2O3 phase was formed on the surface of the film by annealing the film at an elevated temperature under oxygen ambient. The formation
of In2O3/Cu/SiO2 improved the resistivity, adhesion to SiO2, and passivative capability of the studied film. A dramatic reduction in the resistivity of the film occurred at 500 °C,
and was considered to be associated with preferential indium segregation during annealing, yielding a low resistivity below
2.92 μΩcm. The results of this study can be potentially exploited in the application of thin-film transistor–liquid crystal display
gate electrodes and copper metallization in integrated circuits. 相似文献