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文章归纳了2020年电子电路产业一些技术热点,主要有5G电路板设计和基材,制造方面半加成法、3D打印、直接金属化孔电镀和垂直互连结构等技术,以及集成电路封装载板技术。 相似文献
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论文在对现有一类典型图像混沌加密算法的分析基础上,提出了一种改进的图像混沌加密算法。该算法引入小波变换,可以有效地克服一些混沌加密算法不能抵御已知/选择明文攻击的缺陷。 相似文献
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YT-1000型油压自动调速器在运行中不能维持正常油压、在不增加任何设备的情况下,只改动二次接线的处理方法,就能消除隐患、解决问题。 相似文献
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Transmission of signals, whether on-chip or off-chip, places severe constraints on timing and extracts a large price in energy. New silicon device technologies, such as back-plane CMOS, provide a programmable and adaptable threshold voltage as an additional tool that can be used for low power design. We show that one particularly desirable use of this freedom is energy-efficient high-speed transmission across long interconnects using multi-valued encoding. Our multi-valued CMOS circuits take advantage of the threshold voltage control of the transistors, by using the signal-voltage-to-threshold-voltage span, in order to make area-efficient implementations of 4-PAM (pulse amplitude modulation) transceivers operating at high speed. In a comparison of a variety of published technologies, for signal transmission with interconnects of 10-15 mm length, we show up to 50% improvement in energy for on-chip signal transmission over binary encoding together with higher limits for operating speeds without a penalty in circuit noise margin. 相似文献
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目前的电路仿真软件通常是在电路中所有元件值都是给定的情况下得到一些数值结果,而非解析结果。该文利用Matlab的符号运算功能编程,通过节点列表法,实现了任意线性电路的自动解析求解,为电路分析提供了一个有效的辅助工具。 相似文献
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Education-driven research in CAD 总被引:1,自引:0,他引:1
We argue for a new research category, named education-driven research (EDR), which fills the gap between traditional field-specific research that is not concerned with educational objectives and research in education that focuses on fundamental teaching and learning principles and possibly on their customization to broad areas (such as mathematics or physics), but not to specific disciplines (such as CAD). The objective of EDR is to simplify the formulation of the underlying theoretical foundations and of specific tools and solutions in a specialized domain, so as to make them easy to understand and internalize. As such, EDR is a difficult and genuine research activity, which requires a deep understanding of the specific field and can rarely be carried out by generalists with primary expertise in broad education principles. We illustrate the concept of EDR with three examples in CAD: (1) the Split and Tweak subdivisions of a polygon and its use for generating curves, surfaces, and animations; (2) the construction of a topological partition of a plane induced by an arbitrary arrangement of edges; and (3) a romantic definition of the minimal and Hausdorff distances. These examples demonstrate the value of using analogies, of introducing evocative terminology, and of synthesizing the simplest fundamental building blocks. The intuitive understanding provided by EDR enables the students (and even the instructor) to better appreciate the limitations of a particular solution and to explore alternatives. In particular, in these examples, EDR has allowed the author to: (1) reduce the cost of evaluating a cubic B-spline curve; (2) develop a new subdivision curve that is better approximated by its control polygon than either a cubic B-spline or an interpolating 4-point subdivision curve; (3) discover how a circuit inclusion tree may be used for identifying the faces in an arrangement; and (4) rectify a common misconception about the computation of the Hausdorff error between triangle meshes. We invite the scientific community to encourage the development of EDR by publishing its results as genuine research contributions in peer-reviewed professional journals. 相似文献
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高频数字锁相环的研究 总被引:5,自引:0,他引:5
论文阐述了100MHz数字锁相环的设计过程,用10MHz晶体振荡器对100MHz数字压控振荡器进行锁相,使100MHz输出信号指标得到很大改善。论文还分析了各单元电路,关键点时域波形测试,频谱测试。 相似文献
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