基于C64xDSP的遥测数据RS译码实现

RS码是无线通信遥测信道中最常用的编码方式。TMS320C64x系列DSP是TI公司的高性能定点DSP,该DSP内嵌Galois域运算单元,且对RS译码算法的优化提供支持。文章论述了RS译码算法在C64x系列DSP中的实现过程和优化方法,给出了DSP硬件资源相关寄存器的配置和库函数的调用方法,最后对译码器进行了性能分析。     

工业设计快题表现应试模块课程改革试验

快题表现是工业设计专业学生再深造和就业必要的技能,工科生相较而言存在一定难度,近几年通过效果图课程中的试验,形成了一些实用的经验,以期提高工科生在此模块的能力,增加其应试自信度。     

快节奏形势下高校素质选修课出现的问题及改进探讨

在强化素质教育的大背景下,素质选修课的开设成为高校教育的重要内容和环节。随着现代生活节奏加快,走在思想前沿的大学教育受到冲击,素质教育课的实践效果也出现相应的问题,本文就此类现象加以分析和探讨。     

羽毛球运动员下肢快速力量训练研究

羽毛球运动员的下肢快速力量训练不仅指爆发力训练,起动和二次启动、制动、反应力等快速力量对运动员的能力有非常重要的影响。负重训练法、跳深练习法、组合训练法、综合训练法对运动员提高不同形式的快速力量都有一定效果,但要偏重提高具体的快速力量,在训练中根据运动员的实际情况选择合适的训练方法进行针对性训练。     

Competing priorities: Singaporean teachers’ perspectives on critical literacy

This paper explores a group of Singaporean English language teachers’ knowledge and beliefs about critical literacy as well as their perspectives on how best to teach literacy and critical literacy in Singapore schools. A face-to-face survey was conducted among 58 English language teachers by using open-ended questions. The survey covered various topics related to literacy instruction including text decoding, meaning construction, and critical analysis of texts. The participating teachers believed strongly that reading and writing are transactional and interactional practices. However, they were less certain in their beliefs about teaching critical literacy including the critical, analytical and evaluative aspects of text reading. Some teachers saw a conflict between using time on teaching critical literacy and preparing students to pass their exams. As critical literacy is not a requirement at exams, they found it difficult to justify using time teaching it. The results suggest that the teachers’ belief systems are strongly influenced by the broad macro-structure of the educational system in Singapore and their own educational experiences.     

对少年短跑运动员快速爆发力训练的思考

力量是田径运动的基础,而在全面力量的发展基础上提高速度力量和爆发力是少年短跑运动提高速度的关键因素之一。对于少年选手来说,设计和选择各种力量训练方法必须有利于力量向短跑运动的转移、发挥和利用,这其中重点有针对性的发展少年短跑运动员的快速力量和爆发是持续提高短跑运动成绩的有效途径。     

Decoding the phonics screening check

The statutory ‘phonics screening check’ was introduced in 2012 and reflects the current emphasis in England on teaching early reading through systematic synthetic phonics. The check is intended to assess children's phonic abilities and their knowledge of 85 grapheme–phoneme correspondences (GPCs) through decoding 20 real words and 20 pseudo words. Since the national rollout, little attention has been devoted to the content of the checks. The current paper, therefore, reviews the first three years of the check between 2012 and 2014 to examine how the 85 specified GPCs have been assessed and whether children are only using decoding skills to read the words. The analysis found that out of the 85 GPCs considered testable by the check, just 15 GPCs accounted for 67% of all GPC occurrences, with 27 of the 85 specified GPCs (31.8%) not appearing at all. Where a grapheme represented more than one phoneme, the most frequently occurring pronunciation was assessed in 72.2% of cases, with vocabulary knowledge being required to determine the correct pronunciation within real words where multiple pronunciations were possible. The GPCs assessed, therefore, do not reflect the full range of GPCs that it is expected will be taught within a systematic synthetic phonics approach. Furthermore, children's ability to decode real words is dependent on their vocabulary knowledge, not just their phonic skills. These results question the purpose and validity of the phonics screening check and the role of synthetic phonics for teaching early reading.     

改进的求和生成器的密码分析

利用分别征服攻击、Chepyzhov提出的快速相关攻击以及代数攻击等3种算法对改进的求和生成器进行了密码分析,并分别给出了攻击算法的计算复杂度和所需要的密钥流的长度     

新一代的netfilter网络底层开发结构

Linux的网络安全模块到最新的共有3个版本：ipfwadm，IPCHAINS，netfilter。只要是使用和研究过这三代网络安全模块的用户就能深刘的体会到Linux系统中网络安全的进步和Linux内核版本号的变迁一样迅速。Linux内棱级的网络安全越来越完善、越来越合理、越来越易于更多的人参与进行二次开发。尤其是最后一点最为重要，一个难于扩展的框架在Linux这样一个开放源代码的空间里，无疑是暴殄天物。在原有的IPCHAINS框架中也有诸多的不合理和不明智的设计。本文将详细的描述IPCHAINS的不足与缺陷，详尽的介绍netfilter的整体框架。     

用于计算离散分数阶傅立叶变换的MA-CDFRFT算法改进

基于中心类型DFT矩阵特征分解的MA-CDFRFT(Multiangle Centered Discrete Fractional Fourier Transform)算法在计算一组离散分数阶傅立叶变换DFRFT(Discrete Fractional Fourier Transform)时充分利用FFT运算来减小运算量。结合偶数点离散傅立叶变换DFT(Discrete Fourier Transform)运算的对称性原理，通过数学推导将MA-CDFRFT算法中的一维对称性扩展到频率和变换阶数的二维平面上。利用这个二维对称性原理，改进算法将原算法的主要计算量减小了一半左右。仿真测试结果证明了改进算法的正确性。