飞秒激光激发空气电离的阈值研究

报道在脉宽50fs—22ps，波长800nm脉冲激光作用下的空气电离阈值的研究结果.利用探测等离子体发光信号的方法，实验测量了激发空气电离所需的阈值激光强度.结果表明，当激光脉冲宽度从50fs增加到22ps时，阈值光强I_th从8.7×10¹⁴W/cm²下降到2.7×10¹³W/cm²；I_th经历了由迅速降低逐渐发展为缓慢降低的过程.在50fs—1p     

Single-Proton Pickup Reaction of the Halo Nucleus ^6He on a ^9Be Target at 25 MeV/nucleon

The inclusive differential cross sections of the ^7 Li nucleus in a reaction induced by ^6He on a ^9Be target are measured at an incident energy of 25 MeV/nucleon. Finite-range distorted-wave Born approximation calculations suggest that these ^7 Li particles are formed in a direct single-proton pickup reaction ^9Be（^6He,^7 Li）^8Li. The experimental data can be well reproduced by taking into account of the contributions of both the ground states and the first excited states of ^7Li and ^8Li.     

SDRAM通用控制器的FPGA模块化设计

介绍了一种SDRAM通用控制器的FPGA模块化解决方案.     

加强铁路通信传输安全的有效措施分析

改革开放以来,随着科学技术的不断发展,我国的铁路技术有了相当大的进步。在铁路工作中,通信传输占着一定比重,对整个铁路技术有着重要影响。在铁路通信传输技术给人们带来便利的同时,越来越多的问题也接踵而至,给铁路运输带来了很大的安全隐患。对此,要从实际情况出发,采取恰当的措施办法,从而提高铁路通信传输的安全性。     

客户认知与忠诚度关系实证研究

电信运营商的认知对用户选择有重要的影响,文章在对电信运营企业的总体形象认知与用户忠诚度研究的基础上,进一步分析电信运营企业的品牌形象、网络质量、便利性和服务质量以及资费价格等方面与客户忠诚之间的关系,并通过对某省电信运营商用户的电话及样本,运用结构方程模型对理论假设进行验证。     

基于半定规划的阵列天线方向图旁瓣抑制

基于半定规划理论提出了一种新的阵列天线方向图旁瓣抑制算法。与传统旁瓣抑制方法不同,该方法通过合理设计优化准则,避免了在凸优化问题建模过程中引入近似,保证了波束形成器的最优性;并且使得在压低旁瓣的同时,可准确控制信噪比增益和主瓣宽度到期望的范围之内。该方法对阵列流形没有限制,计算机仿真结果验证了其有效性。     

用嵌入Linux构架无线网络终端

无线网络有着广阔的市场前景,正在成为嵌入式应用中的一个快速增长点.……     

用嵌入Linux构架无线网络终端

无线网络有着广阔的市场前景,正在成为嵌入式应用中的一个快速增长点.     

High throughput N-modular redundancy for error correction design of memristive stateful logic

Memristive stateful logic is one of the most promising candidates to implement an in-memory computing system that computes within the storage unit. It can eliminate the costs for the data movement in the traditional von Neumann system. However, the instability in the memristors is inevitable due to the limitation of the current fabrication technology, which incurs a great challenge for the reliability of the memristive stateful logic. In this paper, the implication of device instability on the reliability of the logic event is simulated. The mathematical relationship between logic reliability and redundancy has been deduced. By combining the mathematical relationship with the vector-matrix multiplication in a memristive crossbar array, the logic error correction scheme with high throughput has been proposed. Moreover, a universal design paradigm has been put forward for complex logic. And the circuit schematic and the flow of the scheme have been raised. Finally, a 1-bit full adder (FA) based on the NOR logic and NOT logic is simulated and the mathematical evaluation is performed. It demonstrates the scheme can improve the reliability of the logic significantly. And compared with other four error corrections, the scheme which can be suitable for all kinds of R-R logics and V-R logics has the best universality and throughput. Compared with the other two approaches which also need additional complementary metal-oxide semiconductor (CMOS) circuits, it needs fewer transistors and cycles for the error correction.