基于Arduino的MiFare射频卡读写机制的研究

本文阐述了在Arduino UNO上对MiFare One卡射频识别卡进行读写的软件实现,并重点描述了阅读器与卡片之间的通信过程。     

非封闭的SIS确定模型与随机模型的研究

文章通过对具常数输入人口,死亡率和出生率的的SIS模型的确定形式与随机形式的研究,得到文中定义的基本再生数R0燮1时,传染病最终会消失,而当基本再生数大于等1时,传染病人数将稳定,传染病最终会形成地方病,最后验证了两种模型的结果是一致的。     

提高汽油辛烷值的方法研究

文章从工艺、油品调和及添加剂的使用几个方面提出了提高汽油辛烷值的方法,并作做简单分析。     

ALLOWING FOR JUMP MEASUREMENTS IN VOLATILITY: A HIGH‐FREQUENCY FINANCIAL DATA ANALYSIS OF INDIVIDUAL STOCKS

Following recent advances in the non‐parametric realized volatility approach, we separately measure the discontinuous jump part of the quadratic variation process for individual stocks and incorporate it into heterogeneous autoregressive volatility models. We analyse the distributional properties of the jump measures vis‐à‐vis the corresponding realized volatility ones, and compare them to those of aggregate US market index series. We also demonstrate important gains in the forecasting accuracy of high‐frequency volatility models.     

基于区间数向量投影的主要防御方向选择

一种基于区间数向量投影的主要防御方向选择方法。针对评价指标属性和权重的区间数,构造正理想方案,计算各方案在正理想方案的投影值,根据投影值完成方案的排序优选。实例分析验证了其有效性和适用性。     

重叠滤波多音系统的频偏性能分析及优化

重叠滤波多音(O-FMT)是针对滤波多音(FMT)系统频谱利用率低的缺点而根据超奈奎斯特(FTN)概念引入子载波重叠得到的方案。鉴于O-FMT系统在频偏环境下的性能缺陷，理论分析了频偏对系统信号各部分的影响，比较了O-FMT与正交频分复用（OFDM）系统的抗频偏性能。针对频偏性能优化问题，提出了基于最佳线性无偏估计（BLUE）的改进盲估计算法，设计了基于频域滤波器系数的内嵌结构进行频偏补偿。仿真实验表明，O-FMT相比OFDM具有更好的抗频偏能力，改进的盲估计算法估计值精度更高，抗干扰、抗衰落能力更强，设计的频偏补偿结构可以使系统获得更好的性能。     

FIPIA with information entropy: A new hybrid method to assess airline service quality

This study proposes “FIPIA with information entropy” as a new, hybrid method to assess airline service quality by identifying the most important priorities for airline passengers and producing recommendations to airline management for optimal resource allocation to improve service quality and customer satisfaction. The proposed method is an improvement over IPA, IPIA and FIPA methods, through the introduction of information entropy and fuzzy logic to the analysis of importance, performance and impact dimensions of airline service quality to improve interpretability and actionability of analysis results. This study also offers airline managers a list of what they should improve in resource allocation in order to increase service quality considering customer satisfaction and create value by managing the relational capital more effectively. The new hybrid method was field-tested by administering a 26-item questionnaire to passengers of a major airline operator, analyzing the responses using the Importance-Performance-Impact Analysis (IPIA) method, fuzzy logic and information entropy. The analysis revealed four main dimensions of airline service quality, namely reliability, assurance, tangibles, empathy and responsiveness with 17 constituent attributes. The case study revealed that (1) resource allocation was adequate only on four attributes; (2) seven service quality attributes were identified as needing further management focus on resource allocation; (3) six service quality attributes received more resources than necessary which should be shifted to other attributes; (4) dimensions of reliability and tangibles needed more focus than others. The proposed hybrid method of FIPIA with information entropy can be employed for any industry where service quality depends on multiple attributes.     

一种改进的CPFSK信号频率估计方法

针对突发信号解调中多普勒频偏大的问题，提出了一种改进的连续相位移频键控信号(CPFSK)频率估计方法。首先接收信号平方运算使信号的调制指数加倍，再通过一次离散傅里叶变换(DFT)，用搜索信号平方谱谱峰的方法实现突发信号频率估计。仿真实验表明，在低信噪比条件下，该算法的频率估计精度比经典的相位差频率估计算法提高了20%；该算法与广泛用于高动态突发信号的频率插值估计算法相比，同道干扰信道下信干比改善可达4 dB，DFT长度缩短约1/3。     

Measuring the effectiveness of US monetary policy during the COVID-19 recession

The COVID-19 recession that started in March 2020 led to an unprecedented decline in economic activity across the globe. To fight this recession, policy makers in central banks engaged in expansionary monetary policy. This paper asks whether the measures adopted by the US Federal Reserve (Fed) have been effective in boosting real activity and calming financial markets. To measure these effects at high frequencies, we propose a novel mixed frequency vector autoregressive (MF-VAR) model. This model allows us to combine weekly and monthly information within a unified framework. Our model combines a set of macroeconomic aggregates such as industrial production, unemployment rates, and inflation with high-frequency information from financial markets such as stock prices, interest rate spreads, and weekly information on the Fed's balance sheet size. The latter set of high-frequency time series is used to dynamically interpolate the monthly time series to obtain weekly macroeconomic measures. We use this setup to simulate counterfactuals in absence of monetary stimulus. The results show that the monetary expansion caused higher output growth and stock market returns, more favorable long-term financing conditions and a depreciation of the US dollar compared with a no-policy benchmark scenario.     

张力控制系统在变频造纸设备中的应用研究

张力控制在变频造纸设备中的应用是造纸业的控制难题。本文构建了变频造纸设备张力控制系统模型,通过张力检测装置采集张力值,经PLC接收和判定,最终组成了直接张力控制系统,有效地保证了张力的恒定。同时采用Simulink工具箱,模拟和分析了Matlab软件环境下张力控制系统的仿真运行,最终证实了张力控制系统在变频造纸设备应用中的可行性,为张力控制系统的后续研究与发展指明了方向。