锁相接收机环路参数选取的一些考虑

本文结合工程实际，推导了某种锁相接收机锁相环传递函数，并就如何选取锁相环环路参数问题进行了分析与设计。     

钻井现场使用的空气压缩机的变频与调速

随着现代工业的发展和环保节能理念的不断提出,并且由于能源供应价格的不断上涨,使人们对工业生产节能降耗、降低生产成本的要求越来越严格。本文正是针对这种要求而对钻井队日常生产中使用最为频繁的压风机进行改造,使之达到既能满足生产工艺的要求,又能节能增效,延长设备使用寿命的要求。     

Are classical option pricing models consistent with observed option second-order moments? Evidence from high-frequency data

As a means of validating an option pricing model, we compare the ex-post intra-day realized variance of options with the realized variance of the associated underlying asset that would be implied using assumptions as in the Black and Scholes (BS) model, the Heston, and the Bates model. Based on data for the S&P 500 index, we find that the BS model is strongly directionally biased due to the presence of stochastic volatility. The Heston model reduces the mismatch in realized variance between the two markets, but deviations are still significant. With the exception of short-dated options, we achieve best approximations after controlling for the presence of jumps in the underlying dynamics. Finally, we provide evidence that, although heavily biased, the realized variance based on the BS model contains relevant predictive information that can be exploited when option high-frequency data is not available.     

The Effect of Alcohol Consumption and Patronage Frequency on Restaurant Tipping

ABSTRACT

The National Restaurant Association projected $376 billion in sales and 11 million employees for the restaurant industry in the year 2000. For the servers and bartenders in the industry, tipping is an important part of their income. Results of this study suggest there are several variables that affect the tip amount by party including the amount of the total bill, customer tipping potential, alcohol consumption, the presence of children in the dining party, patronage frequency, and the age of the patron paying the bill. Patron frequency and the amount of the total bill have a strong influence on tipping, as does the customer's tipping potential as judged by the server. A server can expect larger tips from patrons with no children as opposed to those with children. Also, tips are larger when the patron paying the bill has consumed alcohol. The gender and ethnicity of the patron were found to be nonsignificant, as were seating preference and method of payment.     

基于TMS320C6416的跳频信号自动接收机

WTO为各成员多边博弈提供了一个大舞台,在这个舞台上,各成员通过消除贸易壁垒、开放市场、进行平等的自由贸易,从而给各方带来更多的利益,并使成员有机会平等参与国际竞争。这是WTO吸引广大发展中国家积极加入的根本魅力所在。然而,由于WTO成员在经济发展阶段、经济体制、经济实力、产业结构等基础条件方面的差异,决定了各个成员参与博弈的能力大小及受益多少的迥异。中国作为WTO新成员,作为一个尚处于体制改革攻坚和经济转型面临诸多困难的发展中大国,应在WTO多边博弈中担当建设性角色。担当这种建设性的角色,是中国对外开放新形势的必然要求。中国参与WTO多边博弈必须清楚自己的利益所在,同时考虑其他成员的利益诉求,通过博弈寻找到所有成员都能接受的“平衡点”。     

一种基于PE3236的L频段频率合成器设计

设计了一种L频段频率合成器,该频率合成器采用大规模锁相集成芯片PE3236构成锁相环电路,外加电压预置电路对VCO控制电压进行快速预置,大大缩短了频率捷变时间,并运用相噪最优理论设计环路参数,实现了低杂散、低相噪、快速频率捷变的性能要求.另外,电路设计可靠性高,具有较大的实用性.     

OFDM系统采样钟补偿算法及其FPGA实现

利用数字内插滤波器完成全数字域采样钟同步已广泛应用于OFDM数字接收机中.文中利用两个Farrow结构的内插滤波器,同时提高工作时钟对过采样信号进行数字域内插,完成接收端和发送端之间的采样时钟的完全匹配,并且根据硬件器件的特性和算法结构,逐级进行模块变量定点处理.基于实测数据的分析表明,该FPGA数字域采样钟补偿算法不仅有稳定的性能,而且其模块化设计也有利于更高阶算法或多通道系统的实现.     

对外报告变化对管理决策行为影响的试验分析

本文主要验证在我国现行报告制度下,公司对外报告次数变化导致公司管理当局进行决策的选择行为。由于外部报告产生的资本市场压力会直接或间接影响管理人员的决策行为和决策动机,当决策项目产生的会计盈余时与公司未来长期盈余之间存在矛盾,管理者在进行项目决策时,面临外部报告的资本市场压力,内部代理问题和财务分析师的盈利预测相关因素影响,管理者通常选择短期利润最大化的项目而不是选择长期盈余最大项目,从而导致公司管理层的决策短期化。     

射频电导轮廓的概念及应用

提出了粗糙表面射频电导轮廓的概念及物理意义,介绍了与射频电导轮廓相关的技术指标和测量、计算方法,对射频电导轮廓在分析计算粗糙表面射频等效电导率、优化射频微波器件加工工艺流程等方面的应用情况进行了简介。实验表明,研究成果与实测数据相吻合。     

一种解决超短波电台同/近频相互干扰问题的方案

同一直升机上两部超短波电台在同频率或者近频率工作时,会引起严重的相互干扰,为了解决这一问题,根据电台的收发原理,通过分析找出了解决办法,并结合工程实际对一种电台进行了相应的结构改进.