用于高动态目标探测雷达的相位编码脉冲压缩技术

为避免多普勒频移对相位编码信号脉冲压缩处理的影响,提出了利用已知脉冲编码序列对回波信号进行逐符号共轭点乘的脉冲压缩方法,将对齐的回波信号转换为单频信号,并利用傅里叶变换实现信号能量的积累。理论分析与计算机仿真表明,多普勒频移对脉冲压缩性能无影响。该方法适合于应用到对高动态目标进行探测的雷达系统中。     

Social media bots and stock markets

This study examines the link between information spread by social media bots and stock trading. Based on a large sample of tweets mentioning 55 companies in the FTSE 100 composites, we find significant relations between bot tweets and stock returns, volatility, and trading volume at both daily and intraday levels. These results are also confirmed by an event study of stock response following abnormal increases in the volume of tweets. The findings are robust to various specifications, including controlling for traditional news channel, alternative measures of volatility, information flows in pretrading hours, and different measures of sentiment.     

计算机在控制理论频率法中的应用

介绍了利用计算机在输入系统参数后,能迅速显示和打印出开环幅相频率特性曲线,同时计算相位裕量和增益裕量及判定闭环控制系统稳定性的方法。此课题的研究促进了反馈控制理论中频率法的应用。     

机场噪声预测与计算

采用计权等效连续感觉噪声级LWECPN作为机场噪声评价参数,具体结合机场及周围地区的地形、航班、机种及飞机起降航迹等计算并绘出机场周围地区的等声级噪声暴露图。     

远程开放教育教学模式探讨

本文紧紧围绕远程开放核心概念,以开放教育专科学生为基础调研对象,在＂三阶段教学法＂的教学设计基础上,形成相应的基于网络的教学模式设计,进而形成对三个教学阶段的效果评价,最终试图进行微观层面的教学模式构建,以期激发成人在职学生基于网络的自主学习积极性,找到适合西部地区远程开放教学的模式。     

岩滩水力发电厂500 kV高压并联电抗器的投运分析

通过在岩平线岩滩电厂侧安装高压并联电抗器,有效地改善了机组低谷时段的进相问题,提高了机组运行的稳定性,有效地解决了母线电压偏高和机组进相问题,文章分析了高压并联电抗器在运行过程中产生的影响,为今后制定控制对策提供了参考,对岩滩水力发电厂的安全性和经济运行起到了重要作用.     

The Announcement Effect of an Airport Expansion on Housing Prices

The purpose of this study is to examine the influence of the announcement of a new airport hub on housing prices near the airport. While numerous studies of airport noise have found that high noise levels reduce property values, few have been able to measure the announcement effect on values. The results indicate that after controlling to extraneous influences, housing property prices in a 2.5 mile band from the Greensboro/High Point/Winston Salem metropolitan airport declined approximately 9.2% in the post-announcement period. In the next 1.5-mile band, house prices declined approximately 5.7% in the post-announcement period.     

不同调制方式下高斯信道容量的计算

计算不同调制方式下的信道容量对实际通信系统的信道编译码设计具有重要的理论意义。首先从Shannon信息论出发,介绍了平稳无记忆连续信道与加性白高斯噪声信道容量的定义。接着利用互信息与微分熵的相互关系,推导了几种常用的不同调制方式下高斯信道的容量,并给出了相应的信道容量闭合计算表达式。通过将电力卫星通信信道模拟为高斯信道,对采用无速率信道编码联合不同调制方式的卫星通信进行了数值仿真。仿真结果显示,通过推导得到的闭合表达式计算信道容量,能对实际卫星通信的编码速率、译码启动条件的确定起到很好的理论指导作用。     

经济驱动力与GDP增长关系的实证研究———基于经济动力结构优化视角

以改革开放30年以来的投资、消费、出口与经济增长为研究对象,分析三驾马车对我国经济在不同阶段的动力作用。结合现实经济发展,剖析了各阶段的动力特点。下一阶段,要通过调整三驾马车的增长质量,提高经济发展水平,实现经济增长动力的结构优化。     

Determining the integrated volatility via limit order books with multiple records

The integrated volatility plays an important role in risk management and portfolio selection, the estimation methods regarding the quantity have been widely investigated, either under low-frequency data or high-frequency data, or a combination of both. In this paper, we propose a measure for the integrated volatility via limit order book data with possible presence of multiple records. The estimator is valid under mild conditions and it is easily implemented. The finite sample performance of the proposed estimator has been verified by simulation studies and we apply the method to some real high-frequency data-sets as well.